The Effects of The Industrial Cryogenic Process on The Wear Behaviours of AISI D2 Cold Work Tool Steels

OpenAIRE

Ersöz, Enes; Ovalı, İsmail

2018-01-01

In this study, industrial cryogenic process afterconventional heat treatment process for various holding time was applied toAISI D2 (DIN 1.2379) cold work tool steel. The effects of the industrialcryogenic process on the wear behavior was investigated. In the wear test 5,10and 15 N forces were carried out to all group specimens at a constant shearrate (3,16 m/s) and three different wear distances. Experimental results showthat cryogenic processing of AISI D2 cold work tool steels have a signi...

Microstructure and Mechanical Properties of Thixowelded AISI D2 Tool Steel

Directory of Open Access Journals (Sweden)

M. N. Mohammed

2018-05-01

Full Text Available Rigid perpetual joining of materials is one of the main demands in most of the manufacturing and assembling industries. AISI D2 cold work tool steels is commonly known as non-weldable metal that a high quality joint of this kind of material can be hardly achieved and almost impossible by conventional welding. In this study, a novel thixowelding technology was proposed for joining of AISI D2 tool steel. The effect of joining temperature, holding time and post-weld heat treatment on microstructural features and mechanical properties were also investigated. Acceptable joints without defect were achieved through the welding temperature of 1300 °C, while the welding at lower temperature resulted in a series of cracks across the entire joint that led to spontaneous fracture after joining. Tensile test results showed that maximum joint tensile strength of 271 MPa was achieved at 1300 °C and 10 min holding time, which was 35% of that of D2 base metal. Meanwhile, tensile strength of the joined parts after heat treatment showed a significant improvement over the non-heat treated condition with 560 MPa, i.e., about 70% of that of the strength value of the D2 base metal. This improvement in the tensile strength attributed to the dissolution of some amounts of eutectic chromium carbides and changes in the microstructure of the matrix. The joints are fractured at the diffusion zone, and the fracture exhibits a typical brittle characteristic. The present study successfully confirmed that by avoiding dendritic microstructure, as often resulted from the fusion welding, high joining quality components obtained in the semi-solid state. These results can be obtained without complex or additional apparatuses that are used in traditional joining process.

Tool life and surface roughness of ceramic cutting tool when turning AISI D2 tool steel

International Nuclear Information System (INIS)

Wan Emri Wan Abdul Rahaman

2007-01-01

The tool life of physical vapor deposition (PVD) titanium nitride (TiN) coated ceramic when turning AISI D2 tool steel of hardness 54-55 HRC was investigated. The experiments were conducted at various cutting speed and feed rate combinations with constant depth of cut and under dry cutting condition. The tool life of the cutting tool for all cutting conditions was obtained. The tool failure mode and wear mechanism were also investigated. The wear mechanism that is responsible for the wear form is abrasion and diffusion. Flank wear and crater wear are the main wear form found when turning AISI D2 grade hardened steel with 54-55 HRC using KY 4400 ceramic cutting tool. Additionally catastrophic failure is observed at cutting speed of 183 m/min and feed rate of 0.16 mm/ rev. (author)

Cyclic oxidation of stainless steel ferritic AISI 409, AISI 439 and AISI 441; Oxidacao ciclica dos acos inoxidaveis ferriticos AISI 409, AISI 439 e AISI 441

Energy Technology Data Exchange (ETDEWEB)

Salgado, Maria de Fatima; Santos, Diego Machado dos; Oliveira, Givanilson Brito de, E-mail: fatima.salgado@pq.cnpq.br [Universidade Estadual do Maranhao (CESC/UEMA), Caxias, MA (Brazil). Centro de Estudos Superiores; Rodrigues, Samara Clotildes Saraiva; Brandim, Ayrton de Sa [Instituto Federal do Piaui (PPGEM/IFPI), PI (Brazil); Lins, Vanessa de Freitas Cunha [Universidade Federal de Minas Gerais (IFMG), MG (Brazil)

2014-07-01

Stainless steels have many industrial applications. The cyclic oxidation of ferritic stainless steels technical and scientific importance presents, because they are less susceptible to peeling the austenitic alloys. For the purpose of investigating the behavior of these steels under thermal cycling, cyclic oxidation of AISI 409, AISI 441 and AISI 439 was carried out in a tubular furnace under two different conditions: oxidation by dipping the steel in the synthetic condensate for 10h and without oxidation immersion in the condensate, for up to 1500h at 300° C temperature. Using techniques: SEM, EDS and XRD revealed a microstructure with increased oxidation in the samples were immersed in the condensate. The oxide film remained intact during oxidation for steels 439 and 441 409 The Steel immersed in the condensate was rupture of the film after the 20th cycle of oxidation. The chemical characterization of the films allowed the identification of elements: Chromium, Iron, Aluminium and Silicon To a great extent, Cr{sub 2}O{sub 3}. (author)

Tratamiento térmico del acero inoxidable ferrítico AISI 430L sinterizado en atmósfera de N2-H2

Directory of Open Access Journals (Sweden)

Ruiz-Prieto, J. M.

2005-12-01

Full Text Available In this Work the influence of sintering AISI 430L stainless steel in N2-H2 atmosphere on its properties and microstructure have been studied. The presence of nitrogen in the sintering atmosphere leads to complex nitrides formation the AISI 430L sintered steel microstructure. A subsequent heat treatment was applied to modify this microstructure in order to improve the mechanical properties and corrosion resistance of these ferritic stainless steels.Los aceros inoxidables ferríticos, son aceros que contienen esencialmente cromo (12-30 % junto con níquel y molibdeno en cantidades que, en general, no sobrepasan el 1 % y, en ocasiones, se les adicionan otros elementos como son el aluminio, silicio, titanio o niobio. En el presente trabajo de investigación se ha evaluado la influencia del nitrógeno presente en la atmósfera de sinterización sobre la microestructura y propiedades del acero inoxidable ferrítico AISI 430L. Además, se ha realizado un tratamiento térmico posterior de hipertemple y maduración con el objeto de incrementar las propiedades mecánicas y a corrosión de este acero inoxidable, mediante la modificación microestructural de los nitruros complejos de hierro y cromo precipitados durante la etapa de sinterización.

Cyclic oxidation of stainless steel ferritic AISI 409, AISI 439 and AISI 441

International Nuclear Information System (INIS)

Salgado, Maria de Fatima; Santos, Diego Machado dos; Oliveira, Givanilson Brito de; Lins, Vanessa de Freitas Cunha

2014-01-01

Stainless steels have many industrial applications. The cyclic oxidation of ferritic stainless steels technical and scientific importance presents, because they are less susceptible to peeling the austenitic alloys. For the purpose of investigating the behavior of these steels under thermal cycling, cyclic oxidation of AISI 409, AISI 441 and AISI 439 was carried out in a tubular furnace under two different conditions: oxidation by dipping the steel in the synthetic condensate for 10h and without oxidation immersion in the condensate, for up to 1500h at 300° C temperature. Using techniques: SEM, EDS and XRD revealed a microstructure with increased oxidation in the samples were immersed in the condensate. The oxide film remained intact during oxidation for steels 439 and 441 409 The Steel immersed in the condensate was rupture of the film after the 20th cycle of oxidation. The chemical characterization of the films allowed the identification of elements: Chromium, Iron, Aluminium and Silicon To a great extent, Cr_2O_3. (author)

Effect of cerium and lanthanum on the microstructure and mechanical properties of AISI D2 tool steel

International Nuclear Information System (INIS)

Hamidzadeh, Mohammad Ali; Meratian, Mahmood; Saatchi, Ahmad

2013-01-01

AISI D2 tool steel has excellent wear resistance with high dimensional stability. This type of steel is suitable for making molds. This paper describes investigations into the effect of adding Ce/La on microstructure of AISI D2 type cold work tool steels obtained by means of optical microscopy, scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectrometry (EDS) and image analyzer. The results showed that after modification with Ce/La, the morphology, size and distribution of M 7 C 3 carbides change greatly. The carbide network tends to break, and all carbides are refined and distributed homogeneously in the matrix, and also reduce the size of chromium carbides and increase the dissolution of carbides during heat treatment. The results of mechanical tests show that the toughness of the alloy increased about 75% without reducing the hardness of the alloy

Tribological properties of CrN coatings deposited by nitro-chromizing treatment on AISI D2 steel

Energy Technology Data Exchange (ETDEWEB)

Durmaz, M., E-mail: mdurmaz@sakarya.edu.tr; Abakay, E.; Sen, U.; Sen, S. [Department of Metallurgical and Materials Engineering, Engineering Faculty, Sakarya University, Esentepe Campus, 54187 Sakarya (Turkey); Kilinc, B. [Department of Metallurgical and Materials Engineering, Institute of Arts and Sciences, Sakarya University, Esentepe Campus, 54187 Sakarya (Turkey)

2015-03-30

In this work, the wear test of uncoated and chromium nitride coated AISI D2 cold work tool steel against alumina ball realized at 0.1 m/s sliding speeds and under the loads of 2.5N, 5N and 10N. Steel samples were nitrided at 575°C for 8 h in the first step of the coating process, and then chromium nitride coating was performed thermo-reactive deposition technique (TRD) in a powder mixture consisting of ferro-chromium, ammonium chloride and alumina at 1000°C for 2 h. Nitro-chromized samples were characterized by X-Ray diffraction analysis (XRD), scanning electron microscopy (SEM), micro-hardness and ball on disk wear tests. The coating layer formed on the AISI D2 steel was compact and homogeneous. X-ray studies showed that the phase formed in the coated layer is Cr{sub 2}N. The depth of the layer was 8.15 µm. The average hardness of the layer was 2160±15 HV{sub 0.025}. For uncoated and chromium nitride materials, wear rate increased with increasing load. The results of friction coefficient and wear rate of the tested materials showed that the CrN coating presents the lowest results.

Tribological properties of CrN coatings deposited by nitro-chromizing treatment on AISI D2 steel

International Nuclear Information System (INIS)

Durmaz, M.; Abakay, E.; Sen, U.; Sen, S.; Kilinc, B.

2015-01-01

In this work, the wear test of uncoated and chromium nitride coated AISI D2 cold work tool steel against alumina ball realized at 0.1 m/s sliding speeds and under the loads of 2.5N, 5N and 10N. Steel samples were nitrided at 575°C for 8 h in the first step of the coating process, and then chromium nitride coating was performed thermo-reactive deposition technique (TRD) in a powder mixture consisting of ferro-chromium, ammonium chloride and alumina at 1000°C for 2 h. Nitro-chromized samples were characterized by X-Ray diffraction analysis (XRD), scanning electron microscopy (SEM), micro-hardness and ball on disk wear tests. The coating layer formed on the AISI D2 steel was compact and homogeneous. X-ray studies showed that the phase formed in the coated layer is Cr 2 N. The depth of the layer was 8.15 µm. The average hardness of the layer was 2160±15 HV 0.025 . For uncoated and chromium nitride materials, wear rate increased with increasing load. The results of friction coefficient and wear rate of the tested materials showed that the CrN coating presents the lowest results

Tribological properties of CrN coatings deposited by nitro-chromizing treatment on AISI D2 steel

Science.gov (United States)

Durmaz, M.; Kilinc, B.; Abakay, E.; Sen, U.; Sen, S.

2015-03-01

In this work, the wear test of uncoated and chromium nitride coated AISI D2 cold work tool steel against alumina ball realized at 0.1 m/s sliding speeds and under the loads of 2.5N, 5N and 10N. Steel samples were nitrided at 575°C for 8 h in the first step of the coating process, and then chromium nitride coating was performed thermo-reactive deposition technique (TRD) in a powder mixture consisting of ferro-chromium, ammonium chloride and alumina at 1000°C for 2 h. Nitro-chromized samples were characterized by X-Ray diffraction analysis (XRD), scanning electron microscopy (SEM), micro-hardness and ball on disk wear tests. The coating layer formed on the AISI D2 steel was compact and homogeneous. X-ray studies showed that the phase formed in the coated layer is Cr2N. The depth of the layer was 8.15 µm. The average hardness of the layer was 2160±15 HV0.025. For uncoated and chromium nitride materials, wear rate increased with increasing load. The results of friction coefficient and wear rate of the tested materials showed that the CrN coating presents the lowest results.

Stoichiometric titanium dioxide ion implantation in AISI 304 stainless steel for corrosion protection

International Nuclear Information System (INIS)

Hartwig, A.; Decker, M.; Klein, O.; Karl, H.

2015-01-01

The aim of this study is to evaluate the applicability of highly chemically inert titanium dioxide synthesized by ion beam implantation for corrosion protection of AISI 304 stainless steel in sodium chloride solution. More specifically, the prevention of galvanic corrosion between carbon-fiber reinforced plastic (CFRP) and AISI 304 was investigated. Corrosion performance of TiO 2 implanted AISI 304 – examined for different implantation and annealing parameters – is strongly influenced by implantation fluence. Experimental results show that a fluence of 5 × 10 16 cm −2 (Ti + ) and 1 × 10 17 cm −2 (O + ) is sufficient to prevent pitting corrosion significantly, while galvanic corrosion with CFRP can already be noticeably reduced by an implantation fluence of 5 × 10 15 cm −2 (Ti + ) and 1 × 10 16 cm −2 (O + ). Surface roughness, implantation energy and annealing at 200 °C and 400 °C show only little influence on the corrosion behavior. TEM analysis indicates the existence of stoichiometric TiO 2 inside the steel matrix for medium fluences and the formation of a separated metal oxide layer for high fluences.

Effect of cerium and lanthanum on the microstructure and mechanical properties of AISI D2 tool steel

Energy Technology Data Exchange (ETDEWEB)

Hamidzadeh, Mohammad Ali, E-mail: mahamidzadeh@yahoo.com [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Meratian, Mahmood; Saatchi, Ahmad [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

2013-06-01

AISI D2 tool steel has excellent wear resistance with high dimensional stability. This type of steel is suitable for making molds. This paper describes investigations into the effect of adding Ce/La on microstructure of AISI D2 type cold work tool steels obtained by means of optical microscopy, scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectrometry (EDS) and image analyzer. The results showed that after modification with Ce/La, the morphology, size and distribution of M{sub 7}C{sub 3} carbides change greatly. The carbide network tends to break, and all carbides are refined and distributed homogeneously in the matrix, and also reduce the size of chromium carbides and increase the dissolution of carbides during heat treatment. The results of mechanical tests show that the toughness of the alloy increased about 75% without reducing the hardness of the alloy.

Synthesis and luminescence properties of NaAl{sub 11}O{sub 17}:Mn{sup 2+} green phosphor for white LEDs

Energy Technology Data Exchange (ETDEWEB)

Cao, Renping, E-mail: jxcrp@163.com [College of Mathematics and Physics, Jinggangshan University, Ji’an 343009 (China); Peng, Dedong; Xu, Haidong [College of Mathematics and Physics, Jinggangshan University, Ji’an 343009 (China); Jiang, Shenhua [College of pharmacology and Life Science, Jiujiang University, Jiujiang 332000 (China); Luo, Zhiyang [College of Mechanical Manufacture and Automation, Jinggangshan University, Ji’an 343009 (China); Ao, Hui [College of Mathematics and Physics, Jinggangshan University, Ji’an 343009 (China); Liu, Pan [Scientific Research Office, Jinggangshan University, Ji’an 343009 (China)

2016-10-15

Novel NaAl{sub 11}O{sub 17}:Mn{sup 2+} green phosphor is synthesized by solid-state reaction method in air. The emission band peaking at ~508 nm is observed owing to the {sup 4}T{sub 1}→{sup 6}A{sub 1}({sup 6}S) transition of Mn{sup 2+} ion, and the chromaticity coordinates are (0.0725, 0.6468). The excitation band peaking at ~360, 382, 424, 450, and 490 nm are attributed to {sup 6}A{sub 1}({sup 6}S)→{sup 4}E({sup 4}D), {sup 4}T{sub 2}({sup 4}D), [{sup 4}A{sub 1}({sup 4}G), {sup 4}E({sup 4}G)], {sup 4}T{sub 2}({sup 4}G), and {sup 4}T{sub 1}({sup 4}G) transitions of Mn{sup 2+} ion, respectively, which indicate that NaAl{sub 11}O{sub 17}:Mn{sup 2+} phosphor may be excited by (near) ultraviolet and blue LED chip. The luminous mechanism is explained by Tanabe–Sugano diagram of Mn{sup 2+} ion. The optimal Mn{sup 2+} doping concentration is ~3.5 mol%. The NaAl{sub 11}O{sub 17}:3.5%Mn{sup 2+} phosphor shows high quantum efficiency of ~67.84% with excitation 424 nm. The lifetime decreases from 6.72 to 6.0 ms with increasing Mn{sup 2+} concentration in the range of 0–4 mol%.

Comparative study of AISI M3:2 high speed steel produced through different techniques of manufacturing; Estudo comparativo de acos rapidos AISI M3:2 produzidos por diferentes processos de fabricacao

Energy Technology Data Exchange (ETDEWEB)

Araujo Filho, Oscar Olimpio de

2006-07-01

In this work AISI M3:2 high speed steels obtained through different techniques of manufacturing, submitted to the same heat treatment procedure were evaluated by measuring their mechanical properties of transverse rupture strength and hardness. Sinter 23 obtained by hot isostatic pressing (HIP), VWM3C obtained by the conventional route and a M3:2 high speed steel obtained by cold compaction of water atomized powders and vacuum sintered with and without the addition of a small quantity of carbon were evaluated after the same heat treatment procedure. The vacuum sintered M3:2 high speed steel can be an alternative to the more expensive high speed steel produced by hot isostatic pressing and with similar properties presented by the conventional one. The characterization of the vacuum sintered M3:2 high speed steel was performed by measuring the densities of the green compacts and after the sintering cycle. The sintering produced an acceptable microstructure and densities near to the theoretical. The transverse rupture strength was evaluated by means of three point bending tests and the hardness by means of Rockwell C and Vickers tests. The technique of scanning electronic microscopy (SEM) was used to evaluate the microstructure and to establish a relation with the property of transverse rupture strength. The structure was determined by means of X-ray diffraction (XRD) patterns and the retained austenite was detected to all the conditions of heat treatment. The main contribution of this work is to establish a relation between the microstructure and the mechanical property of transverse rupture strength and to evaluate the AISI M3:2 vacuum sintered high speed steel as an alternative to the similar commercial high speed steels. (author)

Role of the UGT2B17 deletion in exemestane pharmacogenetics.

Science.gov (United States)

Luo, S; Chen, G; Truica, C; Baird, C C; Leitzel, K; Lazarus, P

2018-04-01

Exemestane (EXE) is an aromatase inhibitor used for the prevention and treatment of breast cancer. The major metabolic pathway for EXE is reduction to form the active 17β-dihydro-EXE (17β-DHE) and subsequent glucuronidation to 17β-hydroxy-EXE-17-O-β-D-glucuronide (17β-DHE-Gluc) by UGT2B17. The aim of the present study was to determine the effects of UGT2B17 copy number variation on the levels of urinary and plasma 17β-DHE-Gluc and 17β-DHE in patients taking EXE. Ninety-six post-menopausal Caucasian breast cancer patients with ER+ breast tumors taking 25 mg EXE daily were recruited into this study. UGT2B17 copy number was determined by a real-time PCR copy number variant assay and the levels of EXE, 17β-DHE and 17β-DHE-Gluc were quantified by UPLC/MS in patients' urine and plasma. A 39-fold decrease (P<0.0001) in the levels of creatinine-adjusted urinary 17β-DHE-Gluc was observed among UGT2B17 (*2/*2) subjects vs subjects with the UGT2B17 (*1/*1) genotype. The plasma levels of 17β-DHE-Gluc was decreased 29-fold (P<0.0001) in subjects with the UGT2B17 (*2/*2) genotype vs subjects with UGT2B17 (*1/*1) genotype. The levels of plasma EXE-adjusted 17β-DHE was 28% higher (P=0.04) in subjects with the UGT2B17 (*2/*2) genotype vs subjects with the UGT2B17 (*1/*1) genotype. These data indicate that UGT2B17 is the major enzyme responsible for 17β-DHE-Gluc formation in vivo and that the UGT2B17 copy number variant may play a role in inter-individual variability in 17β-DHE levels in vivo.

Improved hardness of laser alloyed X12CrNiMo martensitic stainless steel

CSIR Research Space (South Africa)

Adebiyi, DI

2011-07-01

Full Text Available The improvement in hardness of X12CrNiMo martensitic stainless steel laser alloyed with 99.9% pure titanium carbide, stellite 6 and two cases of premixed ratio of titanium carbide and stellite 6 [TiC (30 wt.%)- stellite 6 (70 wt.%) and TiC (70 wt...

Wear and Adhesive Failure of Al2O3 Powder Coating Sprayed onto AISI H13 Tool Steel Substrate

Science.gov (United States)

Amanov, Auezhan; Pyun, Young-Sik

2016-07-01

In this study, an alumina (Al2O3) ceramic powder was sprayed onto an AISI H13 hot-work tool steel substrate that was subjected to sanding and ultrasonic nanocrystalline surface modification (UNSM) treatment processes. The significance of the UNSM technique on the adhesive failure of the Al2O3 coating and on the hardness of the substrate was investigated. The adhesive failure of the coating sprayed onto sanded and UNSM-treated substrates was investigated by a micro-scratch tester at an incremental load. It was found, based on the obtained results, that the coating sprayed onto the UNSM-treated substrate exhibited a better resistance to adhesive failure in comparison with that of the coating sprayed onto the sanded substrate. Dry friction and wear property of the coatings sprayed onto the sanded and UNSM-treated substrates were assessed by means of a ball-on-disk tribometer against an AISI 52100 steel ball. It was demonstrated that the UNSM technique controllably improved the adhesive failure of the Al2O3 coating, where the critical load was improved by about 31%. Thus, it is expected that the application of the UNSM technique to an AISI H13 tool steel substrate prior to coating may delay the adhesive failure and improve the sticking between the coating and the substrate thanks to the modified and hardened surface.

Magnetic excitations in Ho2Co17 and Ho2Fe17

International Nuclear Information System (INIS)

Clausen, K.N.

1981-01-01

The low energy part ( 2 Co 17 and Ho 2 Fe 17 have been measured along the three high symmetry directions at a temperature of 4.2 K, using the inelastic neutron scattering technique. The resulting magnon dispersion relations have been interpreted using linear spin wave theory with a Hamiltonian including single ion crystal field anisotropy and isotropic exchange between spatially well localized spins. The R 2 T 17 structure contains two different Ho sites, with the same point symmetry, and from the spin wave results it was concluded that the crystal field anisotropy of the two Ho sites in both Ho 2 Co 17 and Ho 2 Fe 17 were identical. The deduced crystal field parameters for Ho 2 Fe 17 were slightly larger than for Ho 2 Co 17 , and the parameters were of the same order of magnitude as for pure Ho. For Ho 2 Fe 17 the Fe-Fe exchange was found to be anisotropic, and for both compounds the magnetic ordering temperatures of 1178 K for Ho 2 Co 17 and 335 K for Ho 2 Fe 17 were determined by the strong positive 3d-3d exchange. (Auth.)

In vitro human skin permeation of endoxifen: potential for local transdermal therapy for primary prevention and carcinoma in situ of the breast

Directory of Open Access Journals (Sweden)

Lee O

2011-07-01

Full Text Available Oukseub Lee1, David Ivancic1, Robert T Chatterton Jr2, Alfred W Rademaker3, Seema A Khan11Department of Surgery, 2Department of Obstetrics/Gynecology, 3Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USAPurpose: Oral tamoxifen, a triphenylethylene (TPE, is useful for breast cancer prevention, but its adverse effects limit acceptance by women. Tamoxifen efficacy is related to its major metabolites 4-hydroxytamoxifen (4-OHT and N-desmethyl-4-hydroxytamoxifen (endoxifen [ENX]. Transdermal delivery of these to the breast may avert the toxicity of oral tamoxifen while maintaining efficacy. We evaluated the relative efficiency of skin permeation of 4-OHT and ENX in vitro, and tested oleic acid (OA as a permeation-enhancer.Methods: 4-OHT, ENX, and estradiol (E2 (0.2 mg/mL of 0.5 µCi 3H/mg were dissolved in 60% ethanol-phosphate buffer, ±OA (0.1%–5%. Permeation through EpiDermTM (Matek Corp, Ashland, MA and split-thickness human skin was calculated based on the amount of the agents recovered from the receiver fluid and skin using liquid scintillation counting over 24 hours.Results: In the EpiDerm model, the absorption of 4-OHT and ENX was 10%–11%; total penetration (TP was 26%–29% at 24 hours and was decreased by OA. In normal human skin, the absorption of 4-OHT and ENX was 0.3%; TP was 2%–4% at 24 hours. The addition of 1% OA improved the permeation of ENX significantly more than that of 4-OHT (P < 0.004; further titration of OA at 0.25%–0.5% further improved the permeation of ENX to a level similar to that of estradiol.Conclusion: The addition of OA to ENX results in a favorable rapid delivery equivalent to that of estradiol, a widely used transdermal hormone. The transdermal delivery of ENX to the breast should be further developed in preclinical and clinical studies.Keywords: endoxifen, breast cancer prevention, human skin, transdermal, oleic acid

Common variation at 3q26.2, 6p21.33, 17p11.2 and 22q13.1 influences multiple myeloma risk

Science.gov (United States)

Broderick, Peter; Chen, Bowang; Johnson, David C; Försti, Asta; Vijayakrishnan, Jayaram; Migliorini, Gabriele; Dobbins, Sara E; Holroyd, Amy; Hose, Dirk; Walker, Brian A; Davies, Faith E; Gregory, Walter A; Jackson, Graham H; Irving, Julie A; Pratt, Guy; Fegan, Chris; Fenton, James AL; Neben, Kai; Hoffmann, Per; Nöthen, Markus M; Mühleisen, Thomas W; Eisele, Lewin; Ross, Fiona M; Straka, Christian; Einsele, Hermann; Langer, Christian; Dörner, Elisabeth; Allan, James M; Jauch, Anna; Morgan, Gareth J; Hemminki, Kari; Houlston, Richard S; Goldschmidt, Hartmut

2016-01-01

To identify variants for multiple myeloma risk, we conducted a genome-wide association study with validation in additional series totaling 4,692 cases and 10,990 controls. We identified four risk loci at 3q26.2 (rs10936599, P=8.70x10-14), 6p21.33 (rs2285803, PSORS1C2; P= 9.67x10-11), 17p11.2 (rs4273077, TNFRSF13B; P=7.67x10-9) and 22q13.1 (rs877529, CBX7; P=7.63x10-16). These data provide further evidence for genetic susceptibility to this B-cell hematological malignancy and insight into the biological basis of predisposition. PMID:23955597

Curie temperature rising by fluorination for Sm2Fe17

Directory of Open Access Journals (Sweden)

Matahiro Komuro

2013-02-01

Full Text Available Fluorine atoms can be introduced to Sm2Fe17 using XeF2 below 423 K. The resulting fluorinated Sm2Fe17 powders have ferromagnetic phases containing Sm2Fe17FY1(01<1, Sm2Fe17FY2 (12<4, Sm2Fe17, and α-Fe. The unit cell for Sm2Fe17 is elongated by the fluorination. The largest unit cell volume among the rhombohedral Sm2Fe17 compounds is 83.8 nm3, which is 5.8% larger than Sm2Fe17. The rhombohedral Sm2Fe17 with the largest unit cell volume is dissociated above 873 K, and fluorination increases Curie temperature from 403 K for Sm2Fe17 to 675 K. This increase can be explained by the magneto-volume effect.

Stoichiometric titanium dioxide ion implantation in AISI 304 stainless steel for corrosion protection

Energy Technology Data Exchange (ETDEWEB)

Hartwig, A.; Decker, M.; Klein, O.; Karl, H., E-mail: helmut.karl@physik.uni-augsburg.de

2015-12-15

The aim of this study is to evaluate the applicability of highly chemically inert titanium dioxide synthesized by ion beam implantation for corrosion protection of AISI 304 stainless steel in sodium chloride solution. More specifically, the prevention of galvanic corrosion between carbon-fiber reinforced plastic (CFRP) and AISI 304 was investigated. Corrosion performance of TiO{sub 2} implanted AISI 304 – examined for different implantation and annealing parameters – is strongly influenced by implantation fluence. Experimental results show that a fluence of 5 × 10{sup 16} cm{sup −2} (Ti{sup +}) and 1 × 10{sup 17} cm{sup −2} (O{sup +}) is sufficient to prevent pitting corrosion significantly, while galvanic corrosion with CFRP can already be noticeably reduced by an implantation fluence of 5 × 10{sup 15} cm{sup −2} (Ti{sup +}) and 1 × 10{sup 16} cm{sup −2} (O{sup +}). Surface roughness, implantation energy and annealing at 200 °C and 400 °C show only little influence on the corrosion behavior. TEM analysis indicates the existence of stoichiometric TiO{sub 2} inside the steel matrix for medium fluences and the formation of a separated metal oxide layer for high fluences.

Les aciers inoxydables dans les fixations

CERN Document Server

CETIM

2010-01-01

Cet ouvrage, qui fait la synthèse de plusieurs travaux menés par le Cetim, propose une vue d'ensemble sur les aciers inoxydables utilisés pour les fixations. Au sommaire : les normes EN, ISO et ATSM qui s'y rapportent , les désignations symboliques , les nuances et caractéristiques mécaniques , les différentes formes de corrosion, les méthodes pour les détecter , les règles du métier , les mises en oeuvre. L'ouvrage comprend plusieurs fiches matériaux et des tableaux qui présentent les équivalences entre les désignations.

5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrapropynyloxy-2,8,14,20-tetrathiacalix[4]arene

Directory of Open Access Journals (Sweden)

Xiang-Gao Meng

2009-12-01

Full Text Available The title compound [systematic name: 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrapropynyloxy-2,8,14,20-tetrathiacalix[4]arene], C52H56O4S4, is an alkylated product bearing four propyne groups at the lower rim of a 5,11,17,23-tetra-tert-butyl-tetrathiacalix[4]arene. The molecule is located on a crystallographic twofold rotation axis, running through two S atoms and perpendicular to the long axis of the molecule. The four propyne groups, located in an alternate fashion above and below the mean plane of the four S atoms, are almost parallel to the calixarene long axis. The dihedral angle between the two crystallographically independent benzene rings is 86.77 (14°. Two tert-butyl groups are disordered over two positions with site occupancies of 0.59 (2 and 0.41 (2.

High temperature oxidation behavior of austenitic stainless steel AISI 304 in steam of nanofluids contain nanoparticle ZrO2

International Nuclear Information System (INIS)

Prajitno, Djoko Hadi; Syarif, Dani Gustaman

2014-01-01

The objective of this study is to evaluate high temperature oxidation behavior of austenitic stainless steel SS 304 in steam of nanofluids contain nanoparticle ZrO 2 . The oxidation was performed at high temperatures ranging from 600 to 800°C. The oxidation time was 60 minutes. After oxidation the surface of the samples was analyzed by different methods including, optical microscope, scanning electron microscope (SEM) and X-ray diffraction (XRD). X-ray diffraction examination show that the oxide scale formed during oxidation of stainless steel AISI 304 alloys is dominated by iron oxide, Fe 2 O 3 . Minor element such as Cr 2 O 3 is also appeared in the diffraction pattern. Characterization by optical microscope showed that cross section microstructure of stainless steel changed after oxidized with the oxide scale on the surface stainless steels. SEM and x-ray diffraction examination show that the oxide of ZrO 2 appeared on the surface of stainless steel. Kinetic rate of oxidation of austenite stainless steel AISI 304 showed that increasing oxidation temperature and time will increase oxidation rate

Corrosion protection of AISI 1018 steel using Co-doped TiO_2/polypyrrole nanocomposites in 3.5% NaCl solution

International Nuclear Information System (INIS)

Ladan, Magaji; Basirun, Wan Jeffrey; Kazi, Salim Newaz; Rahman, Fariza Abdul

2017-01-01

A polypyrrole nanocomposites (PPy NTCs) have been effectively synthesized in the presence of TiO_2 and Co-doped TiO_2 nanoparticles (NPs) by an in situ chemical oxidative polymerization. Field Emission Scanning Electron Microscopy and Transmission Electron Microscopy revealed a tube shape structure of the PPy. The TEM results confirmed that the nanocomposite size of Co-doped TiO_2/PPy NTCs was smaller than TiO_2/PPy NTCs thereby increasing the interaction between the PPy nanotube and the AISI steel surface. The corrosion performance of the coatings was evaluated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements in 3.5% NaCl solution. The EIS results show that the log |Z| of AISI 1018 coated with Co-doped TiO_2/PPy NTCs and TiO_2/PPy NTCs reached about 8.2 and 6.0 respectively after 30 days of exposure in 3.5% NaCl solution. This is likely due to the increased surface area of the PPy synthesized in the presence of Co-doped TiO_2 NPs. The EIS results are confirmed by the potentiodynamic polarization and open circuit potential values of the Co-doped TiO_2/PPy which indicated little changes between 1 and 30 days of exposure which confirms the protection ability of this coating. . It is evident that the presence of Co-doped TiO_2 NPs can enhance the resistance against corrosion at the steel/electrolyte interface. - Highlights: • Polymerization of pyrrole monomer in the presence of Co-doped TiO_2 decreases the size of the polypyrrole nanotube (PPy NT). • The corrosion protection increases with the increase in PPy NT dispersion. • The corrosion resistance of steel coated with Co-doped TiO_2/PPy NTCs is considerably higher. • TiO_2/PPy with Co doping reduces the charge transfer across the electrolyte/AISI 1018 steel interface.

High temperature oxidation behavior of austenitic stainless steel AISI 304 in steam of nanofluids contain nanoparticle ZrO2

Energy Technology Data Exchange (ETDEWEB)

Prajitno, Djoko Hadi, E-mail: djokohp@batan.go.id; Syarif, Dani Gustaman, E-mail: djokohp@batan.go.id [Research Center for Nuclear Materials and Radiometry, Jl. Tamansari 71, Bandung 40132 (Indonesia)

2014-03-24

The objective of this study is to evaluate high temperature oxidation behavior of austenitic stainless steel SS 304 in steam of nanofluids contain nanoparticle ZrO{sub 2}. The oxidation was performed at high temperatures ranging from 600 to 800°C. The oxidation time was 60 minutes. After oxidation the surface of the samples was analyzed by different methods including, optical microscope, scanning electron microscope (SEM) and X-ray diffraction (XRD). X-ray diffraction examination show that the oxide scale formed during oxidation of stainless steel AISI 304 alloys is dominated by iron oxide, Fe{sub 2}O{sub 3}. Minor element such as Cr{sub 2}O{sub 3} is also appeared in the diffraction pattern. Characterization by optical microscope showed that cross section microstructure of stainless steel changed after oxidized with the oxide scale on the surface stainless steels. SEM and x-ray diffraction examination show that the oxide of ZrO{sub 2} appeared on the surface of stainless steel. Kinetic rate of oxidation of austenite stainless steel AISI 304 showed that increasing oxidation temperature and time will increase oxidation rate.

Taguchi Optimization of Cutting Parameters in Turning AISI 1020 MS with M2 HSS Tool

Science.gov (United States)

Sonowal, Dharindom; Sarma, Dhrupad; Bakul Barua, Parimal; Nath, Thuleswar

2017-08-01

In this paper the effect of three cutting parameters viz. Spindle speed, Feed and Depth of Cut on surface roughness of AISI 1020 mild steel bar in turning was investigated and optimized to obtain minimum surface roughness. All the experiments are conducted on HMT LB25 lathe machine using M2 HSS cutting tool. Ranges of parameters of interest have been decided through some preliminary experimentation (One Factor At a Time experiments). Finally a combined experiment has been carried out using Taguchi’s L27 Orthogonal Array (OA) to study the main effect and interaction effect of the all three parameters. The experimental results were analyzed with raw data ANOVA (Analysis of Variance) and S/N data (Signal to Noise ratio) ANOVA. Results show that Spindle speed, Feed and Depth of Cut have significant effects on both mean and variation of surface roughness in turning AISI 1020 mild steel. Mild two factors interactions are observed among the aforesaid factors with significant effects only on the mean of the output variable. From the Taguchi parameter optimization the optimum factor combination is found to be 630 rpm spindle speed, 0.05 mm/rev feed and 1.25 mm depth of cut with estimated surface roughness 2.358 ± 0.970 µm. A confirmatory experiment was conducted with the optimum factor combination to verify the results. In the confirmatory experiment the average value of surface roughness is found to be 2.408 µm which is well within the range (0.418 µm to 4.299 µm) predicted for confirmatory experiment.

Corrosion protection of AISI 1018 steel using Co-doped TiO{sub 2}/polypyrrole nanocomposites in 3.5% NaCl solution

Energy Technology Data Exchange (ETDEWEB)

Ladan, Magaji, E-mail: ladanmagaji@yahoo.com [Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, 50603 (Malaysia); Department of Pure and Industrial Chemistry, Bayero University Kano (Nigeria); Basirun, Wan Jeffrey, E-mail: jeff@um.edu.my [Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, 50603 (Malaysia); Institute of Nanotechnology and Catalysis (NanoCat), University of Malaya, Kuala Lumpur, 50603 (Malaysia); Kazi, Salim Newaz; Rahman, Fariza Abdul [Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, 50603 (Malaysia)

2017-05-01

A polypyrrole nanocomposites (PPy NTCs) have been effectively synthesized in the presence of TiO{sub 2} and Co-doped TiO{sub 2} nanoparticles (NPs) by an in situ chemical oxidative polymerization. Field Emission Scanning Electron Microscopy and Transmission Electron Microscopy revealed a tube shape structure of the PPy. The TEM results confirmed that the nanocomposite size of Co-doped TiO{sub 2}/PPy NTCs was smaller than TiO{sub 2}/PPy NTCs thereby increasing the interaction between the PPy nanotube and the AISI steel surface. The corrosion performance of the coatings was evaluated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements in 3.5% NaCl solution. The EIS results show that the log |Z| of AISI 1018 coated with Co-doped TiO{sub 2}/PPy NTCs and TiO{sub 2}/PPy NTCs reached about 8.2 and 6.0 respectively after 30 days of exposure in 3.5% NaCl solution. This is likely due to the increased surface area of the PPy synthesized in the presence of Co-doped TiO{sub 2} NPs. The EIS results are confirmed by the potentiodynamic polarization and open circuit potential values of the Co-doped TiO{sub 2}/PPy which indicated little changes between 1 and 30 days of exposure which confirms the protection ability of this coating. . It is evident that the presence of Co-doped TiO{sub 2} NPs can enhance the resistance against corrosion at the steel/electrolyte interface. - Highlights: • Polymerization of pyrrole monomer in the presence of Co-doped TiO{sub 2} decreases the size of the polypyrrole nanotube (PPy NT). • The corrosion protection increases with the increase in PPy NT dispersion. • The corrosion resistance of steel coated with Co-doped TiO{sub 2}/PPy NTCs is considerably higher. • TiO{sub 2}/PPy with Co doping reduces the charge transfer across the electrolyte/AISI 1018 steel interface.

Growth kinetics of boride coatings formed at the surface AISI M2 during dehydrated paste pack boriding

Energy Technology Data Exchange (ETDEWEB)

Doñu Ruiz, M.A., E-mail: mdonur0800@alumno.ipn.mx [Universidad Politécnica del Valle de México UPVM, Grupo Ciencia e Ingeniería de Materiales, Av. Mexiquense S/N Esquina Av. Universidad Politécnica, Col Villa Esmeralda, 54910 Tultitlan (Mexico); López Perrusquia, N.; Sánchez Huerta, D. [Universidad Politécnica del Valle de México UPVM, Grupo Ciencia e Ingeniería de Materiales, Av. Mexiquense S/N Esquina Av. Universidad Politécnica, Col Villa Esmeralda, 54910 Tultitlan (Mexico); Torres San Miguel, C.R.; Urriolagoitia Calderón, G.M. [Instituto Politécnico Nacional, SEPI-ESIME, Unidad Profesional Adolfo López Mateos Zacatenco, Edificio 5, 2do. Piso, Col. Lindavista, CP 07738 México, D.F. (Mexico); Cerillo Moreno, E.A. [Universidad Politécnica del Valle de México UPVM, Grupo Ciencia e Ingeniería de Materiales, Av. Mexiquense S/N Esquina Av. Universidad Politécnica, Col Villa Esmeralda, 54910 Tultitlan (Mexico); Cortes Suarez, J.V. [Univerisdad Autónoma Metropolitana Unidad Azcapotzalco, Av. San Pablo 180 Azcapotzalco 02200, Área de Ciencia de los Materiales, México, D.F. (Mexico)

2015-12-01

The growth kinetics of the boride coatings (FeB and Fe{sub 2}B) at the surface of AISI M2 high speed steels were studied in this work. Boriding thermochemical treatment was carried out by dehydrated paste pack at three different temperatures 1173, 1223, and 1273 K and four exposure times 1, 3, 5, and 7 h, respectively. The presence of FeB and Fe{sub 2}B phases was identified by scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) and X-ray diffraction method. In order to obtain the boron diffusion coefficients at the FeB/Fe{sub 2}B boride coatings, a mathematical model based on the mass balance at the growing interfaces was proposed under certain assumptions. Likewise the parabolic growth constants and the boride incubation time were established as a function of the parameters η (T) and ε (T). The activation energy values estimated for the FeB and Fe{sub 2}B layers were 233.42 and 211.89 kJ mol{sup −1} respectively. A good agreement was obtained between the simulated values of boride layer thicknesses and the experimental results. Finally, empirical relationships of boride coating thickness as a function of boriding temperature and time are presented. - Highlights: • Formed boride coatings at the surface of AISI M2 high speed steels by new process dehydrated paste pack boriding. • The model was based on the mass balance equation at the FeB/Fe{sub 2}B and Fe{sub 2}B/Fe interfaces by considering the boride incubation time. • A good agreement was obtained between the simulated values of boride layers coatings and the experimental results.

Study of Carbide Evolution During Thermo-Mechanical Processing of AISI D2 Tool Steel

Science.gov (United States)

Bombac, D.; Fazarinc, M.; Podder, A. Saha; Kugler, G.

2013-03-01

The microstructure of a cold-worked tool steel (AISI D2) with various thermo-mechanical treatments was examined in the current study to identify the effects of these treatments on phases. X-ray diffraction was used to identify phases. Microstructural changes such as spheroidization and coarsening of carbides were studied. Thermodynamic calculations were used to verify the results of the differential thermal analysis. It was found that soaking temperature and time have a large influence on dissolution, precipitation, spheroidization, and coalescence of carbides present in the steel. This consequently influences the hot workability and final properties.

The human MCP-2 gene (SCYA8): Cloning, sequence analysis, tissue expression, and assignment to the CC chemokine gene contig on chromosome 17q11.2

Energy Technology Data Exchange (ETDEWEB)

Van Coillie, E.; Fiten, P.; Van Damme, J.; Opdenakker, G. [Univ. of Leuven (Belgium)] [and others

1997-03-01

Monocyte chemotactic proteins (MCPs) form a subfamily of chemokines that recruit leukocytes to sites of inflammation and that may contribute to tumor-associated leukocyte infiltration and to the antiviral state against HIV infection. With the use of degenerate primers that were based on CC chemokine consensus sequences, the known MIP-1{alpha}/LD78{alpha}, MCP-1, and MCP-3 genes and the previously unidentified eotaxin and MCP-2 genes were isolated from a YAC contig from human chromosome 17q11.2. The amplified genomic MCP-2 fragment was used to isolate an MCP-2 cosmid from which the gene sequence was determined. The MCP-2 gene shares with the MCP-1 and MCP-3 genes a conserved intron-exon structure and a coding nucleotide sequence homology of 77%. By Northern blot analysis the 1.0-kb MCP-2 mRNA was predominantly detectable in the small intestine, peripheral blood, heart, placenta, lung, skeletal muscle, ovary, colon, spinal cord, pancreas, and thymus. Transcripts of 1.5 and 2.4 kb were found in the testis, the small intestine, and the colon. The isolation of the MCP-2 gene from the chemokine contig localized it on YAC clones of chromosome 17q11.2, which also contain the eotaxin, MCP-1, MCP-3, and NCC-1/MCP-4 genes. The combination of using degenerate primer PCR and YACs illustrates that novel genes can efficiently be isolated from gene cluster contigs with less redundancy and effort than the isolation of novel ESTs. 42 refs., 5 figs., 2 tabs.

Corrosion Performance of AISI-309 Exposed to Molten Salts V2O5-Na2SO4 at 700°C Applying EIS and Rp Electrochemical Techniques

Directory of Open Access Journals (Sweden)

E. F. Diaz

2015-01-01

Full Text Available The corrosion performance of AISI-309 exposed 5 days to molten salts 50 mol% V2O5-50 mol% Na2SO4 at 700°C is reported in this paper. Such evaluation was made using three electrochemical techniques: potentiodynamic polarization curve (PC, electrochemical impedance spectroscopy (EIS, and linear polarization resistance (Rp. From PC, the Tafel slopes, Icorr, and Ecorr were obtained. From Nyquist and Bode plots, it was possible to determine two different stages; the first one showed just one loop, which indicated the initial formation of Cr2O3 layer over the metallic surface; after that, the dissolution of Cr2O3 formed a porous layer, which became part of the corrosion products; at the same time a NiO layer combined with sulfur was forming, which was suggested as the second stage, represented by two capacitive loops. EIS plots were in agreement with the physical characterization made from SEM and EDS analyses. Fitting of EIS experimental data allowed us to propose two electrical circuits, being in concordance with the corrosion stages. Parameters obtained from the simulation of EIS data are also reported. From the results, it was stated that AISI-309 suffered intergranular corrosion due to the presence of sulfur, which diffused to the metallic surface through a porous Cr2O3 layer.

CRYOGENIC AND STRESS RELIEF THERMAL TREATMENTS IN AN AISI D2 STEEL

Directory of Open Access Journals (Sweden)

Paula Fernanda da Silva Farina

2012-06-01

Full Text Available The effects of cryogenic treatments on an AISI D2 cold work tool steel using X-ray diffraction from syncronton radiation are studied. The aim of this work is to verify the effects of: i time at cryogenic temperatures (3, 10 and 30 hours; ii cryogenic temperatures (–80°C and –196°C; iii stress relief heat treatment (130°C before cryogenic treatments; iv effect of double tempering at 520°C for 2 hours each time, after cryogenic treatment at –196°C for 30 hours, with and without previous stress relief. X-ray diffraction experiments were conducted at the line D10B-XPD of the Laboratório Nacional de Luz Síncrotron and the experimental results were treated using Rietveld refining, with TOPAS Academic in conjunction with cards from the ICCD-PDF 2006 database for austenite, martensite and carbides M7C3and M2C. Tempered samples were characterized using SEM and SEM-FEG. Volume fraction of retained austenite and carbides, as well as changes in the crystal lattices of martensite and austenite are obtained from the X-ray experiments.

Comparative study of AISI M3:2 high speed steel produced through different techniques of manufacturing

International Nuclear Information System (INIS)

Araujo Filho, Oscar Olimpio de

2006-01-01

In this work AISI M3:2 high speed steels obtained through different techniques of manufacturing, submitted to the same heat treatment procedure were evaluated by measuring their mechanical properties of transverse rupture strength and hardness. Sinter 23 obtained by hot isostatic pressing (HIP), VWM3C obtained by the conventional route and a M3:2 high speed steel obtained by cold compaction of water atomized powders and vacuum sintered with and without the addition of a small quantity of carbon were evaluated after the same heat treatment procedure. The vacuum sintered M3:2 high speed steel can be an alternative to the more expensive high speed steel produced by hot isostatic pressing and with similar properties presented by the conventional one. The characterization of the vacuum sintered M3:2 high speed steel was performed by measuring the densities of the green compacts and after the sintering cycle. The sintering produced an acceptable microstructure and densities near to the theoretical. The transverse rupture strength was evaluated by means of three point bending tests and the hardness by means of Rockwell C and Vickers tests. The technique of scanning electronic microscopy (SEM) was used to evaluate the microstructure and to establish a relation with the property of transverse rupture strength. The structure was determined by means of X-ray diffraction (XRD) patterns and the retained austenite was detected to all the conditions of heat treatment. The main contribution of this work is to establish a relation between the microstructure and the mechanical property of transverse rupture strength and to evaluate the AISI M3:2 vacuum sintered high speed steel as an alternative to the similar commercial high speed steels. (author)

Laser transformation hardening effect on hardening zone features and surface hardness of tool steel AISI D2

Directory of Open Access Journals (Sweden)

D. Lesyk

2017-06-01

Full Text Available The relationship of technological input regimes of the laser transformation hardening on change the hardening depth, hardening width, and hardening angle, as well as surface hardness of the tool steel AISI D2 using multifactor experiment with elements of the analysis of variance and regression equations was determined. The laser transformation hardening process implemented by controlling the heating temperature using Nd:YAG fiber laser with scanner, pyrometer and proportional-integral-differential controller. The linear and quadratic regression models are developed, as well as response surface to determine the effect of the heating temperature and feed rate of the treated surface on the energy density of the laser beam, hardening depths, hardening width, hardening angle, and surface hardness are designed. The main effect on the energy density of the laser beam has a velocity laser treatment, on the other hand, the main effect on the geometrical parameters of the laser hardened zone and surface hardness has temperature heating are shown. The optimum magnitudes of the heating temperature (1270 °C and feed rate of the treated surface (90 mm/min for laser transformation hardening of the tool steel AISI D2 using fiber laser with scanner were defined.

Immune complex-mediated autoimmunity in a patient With Smith-Magenis syndrome (del 17p11.2).

Science.gov (United States)

Yang, Jianying; Chandrasekharappa, Settara C; Vilboux, Thierry; Smith, Ann C M; Peterson, Erik J

2014-08-01

Smith-Magenis syndrome (SMS) is a sporadic congenital disorder involving multiple organ systems caused by chromosome 17p11.2 deletions. Smith-Magenis syndrome features craniofacial and skeletal anomalies, cognitive impairment, and neurobehavioral abnormalities. In addition, some SMS patients may exhibit hypogammaglobulinemia. We report the first case of SMS-associated autoimmunity in a woman who presented with adult onset of multiple autoimmune disorders, including systemic lupus erythematosus, antiphospholipid antibody syndrome, and autoimmune hepatitis. Molecular analysis using single-nucleotide polymorphism array confirmed a de novo 3.8-Mb deletion (breakpoints, chr17: 16,660,721-20,417,975), resulting in haploinsufficiency for TACI (transmembrane activator and CAML interactor). Our data are consistent with potential loss of function for the BAFF (B cell-activating factor) receptor TACI as a contributing factor to human autoimmune phenomena.

Electromagnetic nondestructive evaluation of tempering process in AISI D2 tool steel

Science.gov (United States)

Kahrobaee, Saeed; Kashefi, Mehrdad

2015-05-01

The present paper investigates the potential of using eddy current technique as a reliable nondestructive tool to detect microstructural changes during the different stages of tempering treatment in AISI D2 tool steel. Five stages occur in tempering of the steel: precipitation of ɛ carbides, formation of cementite, retained austenite decomposition, secondary hardening effect and spheroidization of carbides. These stages were characterized by destructive methods, including dilatometry, differential scanning calorimetry, X-ray diffraction, scanning electron microscopic observations, and hardness measurements. The microstructural changes alter the electrical resistivity/magnetic saturation, which, in turn, influence the eddy current signals. Two EC parameters, induced voltage sensed by pickup coil and impedance point detected by excitation coil, were evaluated as a function of tempering temperature to characterize the microstructural features, nondestructively. The study revealed that a good correlation exists between the EC parameters and the microstructural changes.

Squeeze Casting Method Of AI-Si Alloy For Piston Material

International Nuclear Information System (INIS)

Wagiyo, H.; Dani, Muhammad; Sulistioso, G.S.; Pardede, Elman; Handayani, Ari; Teguh, Yulius S.P.P.

2001-01-01

The AI-Si alloy is an alloy used as piston material. This alloys could be as AI-Si hypereutectic alloy (Si content more than 12.5 % wt.), as AI-Si eutectic alloy (Si cuntent 12.5 % wt, and as AI-Si hypoeutectic alloy (Si content less than 12.5 % wt.). The synthesize of AI-Si alloy piston generally using the technique of gravity casting in a dies. This method is causing high porousity. By using the squeeze technique, amount ofporousity in AI-Si alloy is possibly reduced and the density of this alloy should be higher. The other factors such as alloying elements of AI-Si alloy (Mg. Cu, Zn) would increase the mechanical properties especially the hardness. The focuses of this research are the microstructure and the maximum hardness during the heat treatment of AI-Si alloy which was added by alloying elments. The result of hardness at test shows the maximum hardness at 94.7 kg/mm 2 obtained at aging temperature of 210 o C for hours with homogenous dendritic microstructure

The effect of some heat treatment parameters on the dimensional stability of AISI D2

Science.gov (United States)

Surberg, Cord Henrik; Stratton, Paul; Lingenhöle, Klaus

2008-01-01

The tool steel AISI D2 is usually processed by vacuum hardening followed by multiple tempering cycles. It has been suggested that a deep cold treatment in between the hardening and tempering processes could reduce processing time and improve the final properties and dimensional stability. Hardened blocks were then subjected to various combinations of single and multiple tempering steps (520 and 540 °C) and deep cold treatments (-90, -120 and -150 °C). The greatest dimensional stability was achieved by deep cold treatments at the lowest temperature used and was independent of the deep cold treatment time.

Antinociceptive action of DBO 17 and DBO 11 in mice: two 3,8 diazabicyclo (3.2.1.) octane derivates with selective mu opioid receptor affinity.

Science.gov (United States)

Fadda, P; Barlocco, D; Tronci, S; Cignarella, G; Fratta, W

1997-11-01

Two 3,8 diazabicyclo (3.2.1.) octane derivates, namely DBO 17 and DBO 11, were studied for the opioid-like activity. In the rat brain membrane preparation binding studies, DBO 17 and DBO 11 showed a high affinity and selectivity for the mu opioid receptor (Ki's: 5.1 and 25 nM, respectively). DBO 17 and DBO 11 inhibited the nociceptive response in the hot-plate test of mice with ED50 values of 0.16 mg/kg and 0.44 mg/kg, respectively. The antinociceptive action of both DBO 17 and DBO 11 was blocked by naloxone. Tolerance to the antinociceptive action of DBO 17 and DBO 11 was present after 13 and 7 days of repeated treatment, respectively. Both DBO 17 and DBO 11 were ineffective in morphine-tolerant mice and vice versa. Chronic treatments (three times daily for seven consecutive days) of DBO 17 and DBO 11 induced a naloxone-precipitated withdrawal syndrome in DBO 17 treated mice similar to that in morphine treated mice, whereas in DBO 11 treated mice abstinence signs were virtually absent. These results indicate an interesting pharmacological profile that suggests these compounds as possible new candidates for the clinical treatment of pain.

The study of tribological and corrosion behavior of plasma nitrided 34CrNiMo6 steel under hot and cold wall conditions

International Nuclear Information System (INIS)

Maniee, A.; Mahboubi, F.; Soleimani, R.

2014-01-01

Highlights: • 34CrNiMo6 steel was plasma nitrided under hot and cold wall conditions. • The amount of ε phase in hot wall condition was more than that of cold wall condition. • Wear resistance of hot wall nitrided samples was more than cold wall treated ones. • Hot wall nitriding provides better corrosion behavior than cold wall nitriding. - Abstract: This paper reports on a comparative study of tribological and corrosion behavior of plasma nitrided 34CrNiMo6 low alloy steel under modern hot wall condition and conventional cold wall condition. Plasma nitriding was carried out at 500 °C and 550 °C with a 25% N 2 + 75% H 2 gas mixture for 8 h. The wall temperature of the chamber in hot wall condition was set to 400 °C. The treated specimens were characterized by using scanning electron microscopy (SEM), X-ray diffraction (XRD), microhardness and surface roughness techniques. The wear test was performed by pin-on-disc method. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests were also used to evaluate the corrosion resistance of the samples. The results demonstrated that in both nitriding conditions, wear and corrosion resistance of the treated samples decrease with increasing temperature from 500 °C to 550 °C. Moreover, nitriding under hot wall condition at the same temperature provided slightly better tribological and corrosion behavior in comparison with cold wall condition. In consequence, the lowest friction coefficient, and highest wear and corrosion resistance were found on the sample treated under hot wall condition at 500 °C, which had the maximum surface hardness and ε-Fe 2–3 N phase

Influence of cryogenic treatment on microstructure and mechanical properties of high strength AISI D2 tool steel =

Science.gov (United States)

Ghasemi Nanesa, Hadi

Cryogenic treatment, known as treating materials at sub-zero temperatures, has been added to conventional heat treatment cycle of high alloyed steels where martensitic transformation is incomplete after quenching to room temperature. Incomplete martensitic transformation occurs due to the effect of high content of alloying elements on pushing down martensite start and finish temperatures to very low values, specifically, on tool steels. In spite of obtaining significant improvements in mechanical and wear properties after cryogenic treatment, there is no cohesive picture about what exactly modifies the microstructure of tool steels during cryogenic treatment and therefore divergent opinions on the influence of process parameters are still reported. For example, the suggested time length for cryogenic treatment starts from few seconds to several days indicating the lack of understanding about micromechanisms responsible for microstructural evolution while holding at cryogenic temperatures. In this regard, the main objective of this project is to develop a better understanding on the fundamental micromechanisms operating during cryogenic treatment. To attain this objective, the following milestones are pursued. - To study the conventional cryogenic treatment and finding challenges. - To identify and characterize the optimum starting microstructure before cryogenic treatment. - To determine the important processing parameters those control the evolution of microstructure and hardness. - To investigate the interaction between carbide precipitation and martensitic transformation in the AISI D2 steel. - To propose an optimal cryogenic treatment for AISI D2 steel.

Microstructure evolution and texture development in a friction stir-processed AISI D2 tool steel

Science.gov (United States)

Yasavol, N.; Abdollah-zadeh, A.; Vieira, M. T.; Jafarian, H. R.

2014-02-01

Crystallographic texture developments during friction stir processing (FSP) of AISI D2 tool were studied with respect to grain sizes in different tool rotation rates. Comparison of the grain sizes in various rotation rates confirmed that grain refinement occurred progressively in higher rotation rates by severe plastic deformation. It was found that the predominant mechanism during FSP should be dynamic recovery (DRV) happened concurrently with continuous dynamic recrystallization (CDRX) caused by particle-stimulated nucleation (PSN). The developed shear texture relates to the ideal shear textures of D1 and D2 in bcc metals. The prevalence of highly dense arrangement of close-packed planes of bcc and the lowest Taylor factor showed the lowest compressive residual stress which is responsible for better mechanical properties compared with the grain-precipitate refinement.

Processing of an AISI D2 tool steel by high-energy milling

International Nuclear Information System (INIS)

Spagnol, N.J.R.; Araujo, G.F.; Vurobi Junior, S.; Cintho, O.M.

2009-01-01

Full text: Chips of machining of AISI D2 steel were processed in Spex high-energy mill. The powder obtained was analyzed by x-ray diffraction, and then compressed in the form of discs of 8mm in diameter. The samples were treated at 1200 deg C for 1 hour under vacuum atmosphere for sintering. Then specimens were subjected to annealing, quenching and tempering at 400°C and 525 deg C. Along with each disc, a sample of as-received steel was subjected to the same heat treatment to evaluate the final microstructures. After metallographic preparation, samples were etched with Berah's reagent, characterized by optical microscopy, Vickers hardness, quantitative metallography and scanning electron microscopy with micro analysis and mapping by EDS. Specimens from high energy milling had reduction in prior austenitic grain size and more refined carbides and better distributed in the microstructure of steel. (author)

Shot Peening Effects on Subsurface Layer Properties and Fatigue Performance of Case-Hardened 18CrNiMo7-6 Steel

Directory of Open Access Journals (Sweden)

H. S. Ho

2018-01-01

Full Text Available The present study is conducted with a dual-aim: firstly, to examine the effect of several single shot peening conditions on the subsurface layer properties and fatigue performance of the case-hardened 18CrNiMo7-6 steel, and secondly, to propose an optimized peening condition for improved fatigue performance. By carrying out the subsurface integrity analysis and fatigue testing, the underlying relationships among the peening process, subsurface layer property and fatigue performance are investigated, the way peening conditions affect the fatigue life and its associated scatter for the case-hardened 18CrNiMo7-6 steel is quantitatively assessed. The in-depth study shows that dual peening can be an optimized solution, for it is able to produce a subsurface layer with enhanced properties and eventually gain a significant improvement in fatigue performance.

Microstructure and pitting corrosion of 13CrNiMo weld metals

International Nuclear Information System (INIS)

Bilmes, P.D.; Llorente, C.L.; Saire Huaman, L.; Gassa, L.M.; Gervasi, C.A.

2006-01-01

Cyclic potentiodynamic measurements and scanning electron microscopy were used to analyze susceptibility to pitting corrosion of 13CrNiMo weld metals. In order to carry out a critical assessment of the influence of microstructural factors on localized corrosion, different heat treatments were applied to the alloys under investigation. Volume fractions of austenite in tempered conditions as well as the amount and size of precipitated carbides strongly affect pitting resistance. Characteristic potentials (pitting potential and repassivation potential) increase according to the retained austenite content. Results can be discussed in terms of a model that describes the structural refinement resulting from a double-tempering procedure

Regression Modeling of EDM Process for AISI D2 Tool Steel with RSM

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Shakir M. Mousa

2018-01-01

Full Text Available In this paper, Response Surface Method (RSM is utilized to carry out an investigation of the impact of input parameters: electrode type (E.T. [Gr, Cu and CuW], pulse duration of current (Ip, pulse duration on time (Ton, and pulse duration off time (Toff on the surface finish in EDM operation. To approximate and concentrate the suggested second- order regression model is generally accepted for Surface Roughness Ra, a Central Composite Design (CCD is utilized for evaluating the model constant coefficients of the input parameters on Surface Roughness (Ra. Examinations were performed on AISI D2 tool steel. The important coefficients are gotten by achieving successfully an Analysis of Variance (ANOVA at the 5 % confidence interval. The outcomes discover that Surface Roughness (Ra is much more impacted by E.T., Ton, Toff, Ip and little of their interactions action or influence. To predict the average Surface Roughness (Ra, a mathematical regression model was developed. Furthermore, for saving in time, the created model could be utilized for the choice of the high levels in the EDM procedure. The model adequacy was extremely agreeable as the constant Coefficient of Determination (R2 is observed to be 99.72% and adjusted R2-measurement (R2adj 99.60%.

Characterization of AISI 4140 borided steels

International Nuclear Information System (INIS)

Campos-Silva, I.; Ortiz-Dominguez, M.; Lopez-Perrusquia, N.; Meneses-Amador, A.; Escobar-Galindo, R.; Martinez-Trinidad, J.

2010-01-01

The present study characterizes the surface of AISI 4140 steels exposed to the paste-boriding process. The formation of Fe 2 B hard coatings was obtained in the temperature range 1123-1273 K with different exposure times, using a 4 mm thick layer of boron carbide paste over the material surface. First, the growth kinetics of boride layers at the surface of AISI 4140 steels was evaluated. Second, the presence and distribution of alloying elements on the Fe 2 B phase was measured using the Glow Discharge Optical Emission Spectrometry (GDOES) technique. Further, thermal residual stresses produced on the borided phase were evaluated by X-ray diffraction (XRD) analysis. The fracture toughness of the iron boride layer of the AISI 4140 borided steels was estimated using a Vickers microindentation induced-fracture testing at a constant distance of 25 μm from the surface. The force criterion of fracture toughness was determined from the extent of brittle cracks, both parallel and perpendicular to the surface, originating at the tips of an indenter impression. The fracture toughness values obtained by the Palmqvist crack model are expressed in the form K C (π/2) > K C > K C (0) for the different applied loads and experimental parameters of the boriding process.

Characterization of AISI 4140 borided steels

Science.gov (United States)

Campos-Silva, I.; Ortiz-Domínguez, M.; López-Perrusquia, N.; Meneses-Amador, A.; Escobar-Galindo, R.; Martínez-Trinidad, J.

2010-02-01

The present study characterizes the surface of AISI 4140 steels exposed to the paste-boriding process. The formation of Fe 2B hard coatings was obtained in the temperature range 1123-1273 K with different exposure times, using a 4 mm thick layer of boron carbide paste over the material surface. First, the growth kinetics of boride layers at the surface of AISI 4140 steels was evaluated. Second, the presence and distribution of alloying elements on the Fe 2B phase was measured using the Glow Discharge Optical Emission Spectrometry (GDOES) technique. Further, thermal residual stresses produced on the borided phase were evaluated by X-ray diffraction (XRD) analysis. The fracture toughness of the iron boride layer of the AISI 4140 borided steels was estimated using a Vickers microindentation induced-fracture testing at a constant distance of 25 μm from the surface. The force criterion of fracture toughness was determined from the extent of brittle cracks, both parallel and perpendicular to the surface, originating at the tips of an indenter impression. The fracture toughness values obtained by the Palmqvist crack model are expressed in the form KC( π/2) > KC > KC(0) for the different applied loads and experimental parameters of the boriding process.

Characterization of AISI 4140 borided steels

Energy Technology Data Exchange (ETDEWEB)

Campos-Silva, I., E-mail: icampos@ipn.mx [Instituto Politecnico Nacional, Grupo Ingenieria de Superficies, SEPI-ESIME U.P. Adolfo Lopez Mateos, Zacatenco, Mexico D.F., 07738 (Mexico); Ortiz-Dominguez, M.; Lopez-Perrusquia, N.; Meneses-Amador, A. [Instituto Politecnico Nacional, Grupo Ingenieria de Superficies, SEPI-ESIME U.P. Adolfo Lopez Mateos, Zacatenco, Mexico D.F., 07738 (Mexico); Escobar-Galindo, R. [Instituto de Ciencia de Materiales de Madrid (CSIC), E-28049 Cantoblanco, Madrid (Spain); Martinez-Trinidad, J. [Instituto Politecnico Nacional, Grupo Ingenieria de Superficies, SEPI-ESIME U.P. Adolfo Lopez Mateos, Zacatenco, Mexico D.F., 07738 (Mexico)

2010-02-01

The present study characterizes the surface of AISI 4140 steels exposed to the paste-boriding process. The formation of Fe{sub 2}B hard coatings was obtained in the temperature range 1123-1273 K with different exposure times, using a 4 mm thick layer of boron carbide paste over the material surface. First, the growth kinetics of boride layers at the surface of AISI 4140 steels was evaluated. Second, the presence and distribution of alloying elements on the Fe{sub 2}B phase was measured using the Glow Discharge Optical Emission Spectrometry (GDOES) technique. Further, thermal residual stresses produced on the borided phase were evaluated by X-ray diffraction (XRD) analysis. The fracture toughness of the iron boride layer of the AISI 4140 borided steels was estimated using a Vickers microindentation induced-fracture testing at a constant distance of 25 {mu}m from the surface. The force criterion of fracture toughness was determined from the extent of brittle cracks, both parallel and perpendicular to the surface, originating at the tips of an indenter impression. The fracture toughness values obtained by the Palmqvist crack model are expressed in the form K{sub C}({pi}/2) > K{sub C} > K{sub C}(0) for the different applied loads and experimental parameters of the boriding process.

Discovery and widespread occurrence of polyhalogenated 1,1'-dimethyl-2,2'-bipyrroles (PDBPs) in marine biota

International Nuclear Information System (INIS)

Hauler, Carolin; Martin, René; Knölker, Hans-Joachim; Gaus, Caroline; Mueller, Jochen F.; Vetter, Walter

2013-01-01

Polyhalogenated 1,1′-dimethyl-2,2′-bipyrroles (PDBPs) are halogenated natural products (HNPs) previously shown to bioaccumulate in marine mammals and birds. Since their discovery in 1999, six hexahalogenated and a few lesser halogenated congeners have been identified in diverse marine mammal samples. Here we report the identification of 17 additional hexahalogenated PDBPs in the blubber extract of a humpback dolphin (Sousa chinensis) from Queensland, Australia. Thirteen of these new PDBPs were also detected in an Australian sea cucumber (Holothuria sp.). Additional samples were also tested positive on several new PDBPs, including an Australian venus tuskfish (Choerodon venustus) as well as a white whale (Delphinapterus leucas) and a sperm whale (Physeter macrocephalus) from the Northern Hemisphere. GC/ECNI-MS-SIM quantification of the molecular ions was carried out with the help of synthesized standards. The sum concentration of PDBPs was 1.1 mg/kg lipid in the humpback dolphin and 0.48 mg/kg lipid in the sea cucumber. -- Highlights: •Polyhalogenated 1,1′-dimethyl-2,2′-bipyrroles (PDBPs) are natural products. •17 New hexahalogenated PDBPs were identified in marine biota from Australia. •A humpback dolphin (Sousa chinensis) contained 1.1 mg/kg lipid PDBPs. •New PDBPs were also detected in marine mammals from the Northern Hemisphere. -- Detection of new polyhalogenated 1,1′-dimethyl-2,2′-bipyrroles indicates a higher toxic risk of these halogenated natural products in the marine environment than previously known

Monotonic and Cyclic Behavior of DIN 34CrNiMo6 Tempered Alloy Steel

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Ricardo Branco

2016-04-01

Full Text Available This paper aims at studying the monotonic and cyclic plastic deformation behavior of DIN 34CrNiMo6 high strength steel. Monotonic and low-cycle fatigue tests are conducted in ambient air, at room temperature, using standard 8-mm diameter specimens. The former tests are carried out under position control with constant displacement rate. The latter are performed under fully-reversed strain-controlled conditions, using the single-step test method, with strain amplitudes lying between ±0.4% and ±2.0%. After the tests, the fracture surfaces are examined by scanning electron microscopy in order to characterize the surface morphologies and identify the main failure mechanisms. Regardless of the strain amplitude, a softening behavior was observed throughout the entire life. Total strain energy density, defined as the sum of both tensile elastic and plastic strain energies, was revealed to be an adequate fatigue damage parameter for short and long lives.

Aluminum coating by fluidized bed chemical vapor deposition on austenitic stainless steels AISI 304 and AISI 316

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Jose Luddey Marulanda-Arevalo

2015-01-01

Full Text Available Los revestimientos de aluminio f ueron depositados sobre aceros inoxidables AISI 304 y AISI 316 en el rango de temperatura de 5 60 a 600 °C por deposición química de vapor en lecho fluidizado(CVD – FBR. Se utilizó un lecho que consistía en 10 % de aluminio en polvo y 90 % de lecho inerte (alúmina, el cual fue fluidizado con Ar y como ga ses activadores se utilizó una mezcla de ácido clorhídrico con hidrógeno (HCl/H 2 . En el recubrimiento si n tratamiento térmico están las siguiente s especies: Al 13 Fe 4 , Fe 2 Al 5 , FeAl 2 y Al 5 FeNi, las cuales están presentes para ambos aceros. Además, el tratamiento térmico provoca la difusa de alu minio hacia el sustrato y la difusa de hierro del sustrato haci a la superficie del recubrimiento, haciendo la trans formación de los compuestos ant eriores a FeAl, Fe 2 Al 5 , FeAl 2 , Al 0.99 Fe 0.99 Ni 0.02 , AlNi y el Fe 2 AlCr. Se realizó la simulación termodinámica con el s oftware Thermo Calc para obt ener información de la posible composición y la cantidad de mat erial depositado, para condiciones seleccionadas. Las muestras recubi ertas y sin recubrir, se expus ieron a 750 ºC en una atmósfera d onde el vapor agua se transporta a las muestras usando un flujo de N 2 de 40 ml/min, más 100 % vapor de agua (H 2 O. Los dos sustratos sin revestir se comportaron de manera diferente, ya que el acero AISI 304 soportó bien el a taque y ganó poco peso (0.49 mg/cm 2 , en comparación con el acero AISI 316 que perdió mucho peso (25.4 mg/cm 2 . Los aceros recubiertos ganaron poco de peso durante las mil horas de exposición (0.26 mg/cm 2 y soportaron muy bien el ataque corrosivo en c omparación con sustratos sin r ecubrimiento.

Effect of the hydrogen charging of AISI 316 stainless steel from solutions containing As2 O3

International Nuclear Information System (INIS)

Brito, S.D. de.

1973-01-01

The hydrogen charging of AISI 316 stainless steel has turned unstable the austenitic structure which partially decomposes into two phases: ε (hexagonal close packed) and α ' (body centered cubic). A 1 N H 2 SO 4 solution was used as electrolyte, with varying concentrations of As 2 O 3 (0, 1, 5 and 100 mg/l) for a single constant applied current density (i o = 0,22 A/cm 2 ). It was observed that a smaller austenitic grain as well as a larger hydrogen charging time, improve the phase transformation. It was established that the order in which the transformation products of the austenite appear through hydrogen charging follows the sequence: Y → Y-bar + ε → Y + ε + α ', although there is still some doubt about the equivalent transformation order by plastic deformation. (author)

Development of banded microstructure in 34CrNiMo6 steel

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A. Nagode

2016-07-01

Full Text Available In this paper the development of a banded microstructure in hot-rolled 34CrNiMo6 steel which consisted of bainitic and martensitic bands is explained. The chemical compositions of the bands were measured with energy dispersive x-ray spectroscopy (EDS, which showed that the martensitic bands contained more alloying elements (Mn, Cr, Mo, Si than bainitic bands. By using Oberhoffer reagent, the segregations of phosphorus were also revealed. These phosphorus segregations coincided with the positive segregations of the alloying elements. The continuous cooling transformation (CCT diagrams of steel were calculated. They confirmed the formation of martensite in positive segregations and the formation of bainite in negative segregations.

The surface fatigue life of contour induction hardened AISI 1552 gears

Science.gov (United States)

Townsend, Dennis P.; Turza, Alan; Chaplin, Mike

1995-07-01

Two groups of spur gears manufactured from two different materials and heat treatments were endurance tested for surface fatigue life. One group was manufactured from AISI 1552 and was finished ground to a 0.4 micron (16 micro-in.) rms surface finish and then dual frequency contour induction hardened. The second group was manufactured from CEVM AISI 9310 and was carburized, hardened, and ground to a 0.4 micron (16 micro-in.) rms surface finish. The gear pitch diameter was 8.89 cm (3.5 in.). Test conditions were a maximum Hertz stress of 1.71 GPa (248 ksi), a bulk gear temperature of approximately 350 K (170 F) and a speed of 10,000 rpm. The lubricant used for the tests was a synthetic paraffinic oil with an additive package. The test results showed that the 10 percent surface fatigue (pitting) life of the contour hardened AISI 1552 test gears was 1.7 times that of the carburized and hardened AISI 9310 test gears. Also there were two early failures of the AISI 1552 gears by bending fatigue.

Diffusional Growth Kinetics Analisys of Fe2B Layers Applied During the Coating Powder-Pack Boriding Process on an AISI 1026 Steel

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M. Elias-Espinosa

2015-01-01

Full Text Available La exigencia de emplear materiales con propiedades avanzadas incluyen la necesidad de aplicar recubrimientos de alta resistencia que alarguen la vida de útil de aceros comerciales, de esta forma, el tratamiento termoquímico de borurización tiene el potencial para cumplir estos requerimientos. En este trabajo de investigación se formula un modelo matemático para analizar la cinética de crecimiento de las capas de 2 Fe B formadas sobre la superficie de un acero AISI 1026. El modelo matemático propuesto se desarrolló en base a la solución de la ecuación de balance de masa de la interface de crecimiento 2 Fe B/Fe para evaluar el coeficiente de difusión del boro a través de las capas de Fe2B en un rango de temperaturas de 1123 a1273 K. En el modelo desarrollado se incluyó el tiempo de incubación del boruro para formar la fase Fe2B. El modelo matemático fue validado con datos experimentales realizados a una temperatura de 1253 K y tiempo de siete horas. Las capas de boruro fueron caracterizadas y analizadas por microscopia óptica y de barrido (se obtuvo un EDS, así como por Difracción de Rayos – X (XRD. Se utilizó la técnica de indentación Daimler-Benz Rockwell-C para evaluar cualitativamente la adherencia de la capa de Fe2B sobre el sustrato (acero AISI 1026. Para usos prácticos y para un espesor determinado, se propuso un diagrama a espesor constante (215 μm el cual es controlado con la variación de la temperatura y tiempo de exposición al recubrimiento. De los resultados obtenidos, se encontró que la energía de activación para el boro en el acero AISI 1026 es igual a 178 kJ mol-1.

Electromagnetic nondestructive evaluation of tempering process in AISI D2 tool steel

International Nuclear Information System (INIS)

Kahrobaee, Saeed; Kashefi, Mehrdad

2015-01-01

The present paper investigates the potential of using eddy current technique as a reliable nondestructive tool to detect microstructural changes during the different stages of tempering treatment in AISI D2 tool steel. Five stages occur in tempering of the steel: precipitation of ε carbides, formation of cementite, retained austenite decomposition, secondary hardening effect and spheroidization of carbides. These stages were characterized by destructive methods, including dilatometry, differential scanning calorimetry, X-ray diffraction, scanning electron microscopic observations, and hardness measurements. The microstructural changes alter the electrical resistivity/magnetic saturation, which, in turn, influence the eddy current signals. Two EC parameters, induced voltage sensed by pickup coil and impedance point detected by excitation coil, were evaluated as a function of tempering temperature to characterize the microstructural features, nondestructively. The study revealed that a good correlation exists between the EC parameters and the microstructural changes. - Highlights: • D2 steel parts were tempered at 200-650 °C to produce various microstructures. • Precipitation of ε and Fe 3 C carbides and spheroidization of carbides were detected. • Retained austenite decomposition and secondary hardening effect were determined. • Variations of electrical resistivity (ρ) and magnetic saturation (Bs) were studied. • Combined effects of ρ and Bs on the EC outputs were evaluated

Electromagnetic nondestructive evaluation of tempering process in AISI D2 tool steel

Energy Technology Data Exchange (ETDEWEB)

Kahrobaee, Saeed, E-mail: saeed.kahrobaee@yahoo.com; Kashefi, Mehrdad, E-mail: m-kashefi@um.ac.ir

2015-05-15

The present paper investigates the potential of using eddy current technique as a reliable nondestructive tool to detect microstructural changes during the different stages of tempering treatment in AISI D2 tool steel. Five stages occur in tempering of the steel: precipitation of ε carbides, formation of cementite, retained austenite decomposition, secondary hardening effect and spheroidization of carbides. These stages were characterized by destructive methods, including dilatometry, differential scanning calorimetry, X-ray diffraction, scanning electron microscopic observations, and hardness measurements. The microstructural changes alter the electrical resistivity/magnetic saturation, which, in turn, influence the eddy current signals. Two EC parameters, induced voltage sensed by pickup coil and impedance point detected by excitation coil, were evaluated as a function of tempering temperature to characterize the microstructural features, nondestructively. The study revealed that a good correlation exists between the EC parameters and the microstructural changes. - Highlights: • D2 steel parts were tempered at 200-650 °C to produce various microstructures. • Precipitation of ε and Fe{sub 3}C carbides and spheroidization of carbides were detected. • Retained austenite decomposition and secondary hardening effect were determined. • Variations of electrical resistivity (ρ) and magnetic saturation (Bs) were studied. • Combined effects of ρ and Bs on the EC outputs were evaluated.

Surface characteristics analysis of dry EDMed AISI D2 steel using modified tool design

Energy Technology Data Exchange (ETDEWEB)

Pragadish, N.; Kumar, M. Pradeep [Anna University, Chennai (China)

2015-04-15

A modified tool design is proposed which helps in drilling holes without any central core, and also enables the effective removal of the debris particles. Experiments were conducted on AISI D2 Steel using copper electrode as tool in both conventional EDM and dry EDM processes and the performance of both processes is compared. Experiments were designed using Taguchi's L27 orthogonal array. Discharge current (I), gap voltage (V), pulse on time (T{sub ON}), gas pressure (P) and tool rotational speed (N) were chosen as the various input parameters, and their effect on the material removal rate (MRR), surface roughness (SR), surface morphology, microstructure and elemental composition of the machined surface is analyzed. The experimental results show better surface characteristics in the surface machined under dry EDM process.

Surface characteristics analysis of dry EDMed AISI D2 steel using modified tool design

International Nuclear Information System (INIS)

Pragadish, N.; Kumar, M. Pradeep

2015-01-01

A modified tool design is proposed which helps in drilling holes without any central core, and also enables the effective removal of the debris particles. Experiments were conducted on AISI D2 Steel using copper electrode as tool in both conventional EDM and dry EDM processes and the performance of both processes is compared. Experiments were designed using Taguchi's L27 orthogonal array. Discharge current (I), gap voltage (V), pulse on time (T ON ), gas pressure (P) and tool rotational speed (N) were chosen as the various input parameters, and their effect on the material removal rate (MRR), surface roughness (SR), surface morphology, microstructure and elemental composition of the machined surface is analyzed. The experimental results show better surface characteristics in the surface machined under dry EDM process.

Tribological and mechanical properties of Ti/TiAlN/TiAlCN nanoscale multilayer PVD coatings deposited on AISI H11 hot work tool steel

Energy Technology Data Exchange (ETDEWEB)

AL-Bukhaiti, M.A., E-mail: m.albukhaiti@gmail.com [Mechanical Engineering Department, Faculty of Engineering, Sana’a University, Sana’a 12544 (Yemen); Al-hatab, K.A. [Mechanical Engineering Department, Faculty of Engineering, Sana’a University, Sana’a 12544 (Yemen); Tillmann, W.; Hoffmann, F.; Sprute, T. [Institute of Materials Engineering, Technische Universitat Dortmund, Leonhard-Euler-Str.2, 44227 Dortmund (Germany)

2014-11-01

Highlights: • New Ti/TiAlN/TiAlCN multilayer coating was developed. • It showed low wear rates (10{sup −16} m{sup 3}/N m), low friction coefficients (μ ∼ 0.25), and good hardness (17–20 GPa). • Friction coefficients and wear rates decrease and increase, respectively, with the increase in normal load and sliding velocity. • The coating/Al{sub 2}O{sub 3} pair showed superior wear resistance and low friction coefficient in comparison to coating/100Cr6 pair. - Abstract: A new [Ti/TiAlN/TiAlCN]{sub 5} multilayer coatings were deposited onto polished substrate AISI H11 (DIN 1.2343) steel by an industrial magnetron sputtering device. The tribological performance of the coated system was investigated by a ball-on-disk tribometer against 100Cr6 steel and Al{sub 2}O{sub 3} balls. The friction coefficients and specific wear rates were measured at various normal loads (2, 5, 8, and 10 N) and sliding velocities (0.2, 0.4, and 0.8 m/s) in ambient air and dry conditions. The phase structure, composition, wear tracks morphologies, hardness, and film/substrate adhesion of the coatings were characterized by light-microscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), 3D-surface analyzer, nanoindentation, and scratch tests. Results showed that the deposited coatings showed low wear rates in the scale of 10{sup −15} m{sup 3}/N m, low friction coefficients against 100Cr6 and Al{sub 2}O{sub 3} balls in the range of 0.25–0.37, and good hardness in the range of 17–20 GPa. Results also revealed that the friction coefficients and disc wear rates decrease and increase, respectively with the increase in normal load and sliding velocity for both coating/Al{sub 2}O{sub 3} and coating/100Cr6 sliding system. Compared with the uncoated-H11 substrate, the deposited coating exhibited superior tribological and mechanical properties. The dominant wear mechanism was abrasive wear for coating/Al{sub 2}O{sub 3} pair, while

On the anisotropy energies for YCo5, RCo5, Y2Co17, and R2Co17

International Nuclear Information System (INIS)

Takahashi, H.; Hikosaka, K.; Ohtsuka, S.; Seo, A.; Ukai, T.; Mori, N.

1988-01-01

The approximate d bands for YCo 5 , RCo 5 , Y 2 Co 17 , and R 2 Co 17 (Th 2 Zn 17 and Th 2 Ni 17 type) are formulated by Deegan's prescription and the formulas of Slater and Koster. The experimental results of YCo 5 and Y 2 Co 17 are discussed by using these approximate d bands. For RCo 5 and R 2 Co 17 the discussions are made by adopting the localized model and the band model for 4f electrons

Microhardness measurement in AISI 321 stainless steel with niobium additions before and after fast neutron irradiation

International Nuclear Information System (INIS)

Galli, V.L.; Lucki, G.

1980-01-01

Data about influence of neutron irradiation on the microhardness of stainless steel of type AISI 321 with 0.05 and 0.1wt.% Nb additions are presented. The microhardness measurements were made in the range of 300 to 650 0 C, before and after fast neutron irradiation with fluences about 10 17 n/cm 2 . Our results indicate that radiation damage peaks occur around 480 0 C for the stainless steel of type AISI 321 without Nb addition, around 500 0 C for the composition with 0.05 wt.% Nb addition and around 570 0 C for the composition with 0.1 wt.% Nb addition. Microhardness data are in agreement with those obtained by means of electrical resistivity measurements, performed at the same conditions. (Author) [pt

Genetic Variants in HSD17B3, SMAD3, and IPO11 Impact Circulating Lipids in Response to Fenofibrate in Individuals With Type 2 Diabetes.

Science.gov (United States)

Rotroff, Daniel M; Pijut, Sonja S; Marvel, Skylar W; Jack, John R; Havener, Tammy M; Pujol, Aurora; Schluter, Agatha; Graf, Gregory A; Ginsberg, Henry N; Shah, Hetal S; Gao, He; Morieri, Mario-Luca; Doria, Alessandro; Mychaleckyi, Josyf C; McLeod, Howard L; Buse, John B; Wagner, Michael J; Motsinger-Reif, Alison A

2018-04-01

Individuals with type 2 diabetes (T2D) and dyslipidemia are at an increased risk of cardiovascular disease. Fibrates are a class of drugs prescribed to treat dyslipidemia, but variation in response has been observed. To evaluate common and rare genetic variants that impact lipid responses to fenofibrate in statin-treated patients with T2D, we examined lipid changes in response to fenofibrate therapy using a genomewide association study (GWAS). Associations were followed-up using gene expression studies in mice. Common variants in SMAD3 and IPO11 were marginally associated with lipid changes in black subjects (P < 5 × 10 -6 ). Rare variant and gene expression changes were assessed using a false discovery rate approach. AKR7A3 and HSD17B13 were associated with lipid changes in white subjects (q < 0.2). Mice fed fenofibrate displayed reductions in Hsd17b13 gene expression (q < 0.1). Associations of variants in SMAD3, IPO11, and HSD17B13, with gene expression changes in mice indicate that transforming growth factor-beta (TGF-β) and NRF2 signaling pathways may influence fenofibrate effects on dyslipidemia in patients with T2D. © 2017 American Society for Clinical Pharmacology and Therapeutics.

Nitrogen-containing superlow-carbon austenitic steel 02Kh25N22AM2

Science.gov (United States)

Fe'ldgandler, É. G.; Svistunova, T. V.; Savkina, L. Ya.; Lapshina, O. B.

1996-02-01

At present the equipment for manufacturing carbamide mineral fertilizers is produced from domestic steel 03Kh17N14M3 having "carbamide quality." Imported equipment also used in the industry is produced from steel of the 25-22-2 (Cr -Ni-Mo) type shipped by various firms, namely, 2RE69 (Sandvik, Sweden), 254SFER (Avesta, Sweden), 2522LCN (VDM, Germany), DM 1.4466 (Germany), and X2CrNiMo 25-22-2 (Dalmine, Italy). The imported steels are used because in some units steel 03Khl7Nl4M3 does not provide the requisite corrosion resistance in an intensified process of carbamide manufacturing. We currently possess domestic high-alloyed steel for producing new and repairing imported equipment operating under the severe conditions of carbamide synthesis. The present paper concerns the structure, mechanical properties, and corrosion resistance of industrially produced steel 02Kh25N22AM2 (ChS-108) and the recommended range of its application.

Biochemistry of the normal dura mater of the human brain determination of water, sodium, potassium, calcium, phosphorus, magnesium, copper, iron, sulfur and nitrogen contents Estudo bioquímico da dura mater normal do cérebro humano: conteúdo de água, sódio, potássio, cálcio, fósforo, magnésio, cobre ferro, enxôfre e nitrogênio

Directory of Open Access Journals (Sweden)

Horacio M. Canelas

1969-06-01

Full Text Available The concentrations of water, sodium, potassium, calcium, phosphorus, magnesium, copper, iron, sulfur, and nitrogen were determined in samples of apparently normal dura mater removed from 18 subjects recently dead by craniocerebral trauma. The average concentrations expressed in dry weight were: water 79.55 g/100 g ± 2.52; sodium 1.63 mequiv/100 g ±0.27; potassium 3.68 mequiv/100 g ± 0.66; calcium 119.84 mg/100 g ± 107.40; phosphorus 68.2 mg/100 g ± 34.5; magnesium 0.61 mequiv/100 g ± 0.37; copper 249.8 /xg/100 g ± 109.4; iron 0.82 mg/100 g ± 0.28; sulfur 490.7 mg/100 g ± 22.5; nitrogen 3.33 g/100 g ± 0.17.Foram determinadas as concentrações de água, sódio, potássio, cálcio, fósforo, magnésio, cobre, ferro, enxôfre e nitrogênio de espécimes de dura máter aparentemente normal retirados de 18 indivíduos recentemente falecidos em conseqüência de traumatismo crânio-encefálico. As concentrações médias, expressas em peso seco, foram as seguintes: água 79,55 g/100 g ± 2,52; sódio 1,63 mequiv/100 g ± 0,27; potássio 3,68 mequiv/100 g ± 0,66; cálcio 119,84 mg/100 g ± 107,40; fósforo 68,2 mg/100 g ± 34,5; magnésio 0,61 mequiv/100 g ± 0,37; cobre 249,8 mg/100 ± 109,4; ferro 0,82 mg/100 g ± 0,28; enxôfre 490,7 mg/100 g ± 22,5; nitrogênio 3,33 g/100 g ± 0,17.

Correlation between microstructure and electrical properties of Cu{sub 1.3}Mn{sub 1.7}O{sub 4}/La{sub 2}O{sub 3} composite-coated ferritic stainless steel interconnects

Energy Technology Data Exchange (ETDEWEB)

Hosseini, N., E-mail: nazaneen_hosseini@ma.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Karimzadeh, F.; Abbasi, M.H. [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Choi, G.M. [Fuel Cell Research Center and Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of)

2016-07-15

The goal of this study was to investigate the effect of screen-printed Cu{sub 1.3}Mn{sub 1.7}O{sub 4}/La{sub 2}O{sub 3} composite coating on chromia scale growth and electrical behavior of AISI430 stainless steel interconnects. The coated samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy equipped with energy dispersive spectroscopy (FESEM-EDS) and 4-probe area specific resistance (ASR) tests. The results showed that LaCrO{sub 3} conductive perovskite is formed due to the interdiffusion between Cr{sub 2}O{sub 3} and/or CrO{sub 3} and La{sub 2}O{sub 3}. The presence of LaCrO{sub 3} through the composite coating and Cr{sub 2}O{sub 3} sub-scale accompanied by the effective role of spinel phase, acted as a barrier to mitigate the sub-scale growth preventing chromium diffusion through the coating and the cathode. Besides, LaCrO{sub 3} particles within the sub-scale provided suitable conductive paths decreasing ASR from 19.3 mΩ cm{sup 2} for spinel coated sample to 15 mΩ cm{sup 2} for composite coated sample at the end of 500 h oxidation at 750° C. - Highlights: • Cu{sub 1.3}Mn{sub 1.7}O{sub 4}/La{sub 2}O{sub 3} coating was deposited on AISI 430 by screen-printing method. • LaCrO{sub 3} perovskite was formed due to the interdiffusion between Cr species and La{sub 2}O{sub 3}. • LaCrO{sub 3} particles within the chromia provided conductive paths causing ASR reduction. • The co-existence of LaCrO{sub 3} and Cu{sub 1.3}Mn{sub 1.7}O{sub 4} noticeably retarded the chromia growth.

Evaluation of performance of AISI 444 steel for application in distillation towers; Avaliacao do desempenho do aco AISI 444 para aplicacao como 'lining' em torres de destilacao

Energy Technology Data Exchange (ETDEWEB)

Guimaraes, R.F.; Miranda, H.C. de; Farias, J.P. [Universidade Federal do Ceara (DEMM/UFC), Fortaleza, CE (Brazil). Dept. de Engenharia Metalurgica e de Materiais. Lab. de Caracterizacao de Materiais], e-mail: rf.guimaraes@yahoo.com.br

2008-07-01

In this work, the behavior of the AISI 444 ferritic stainless steel submitted to thermal fatigue test and their corrosion resistance in heavy crude oil was evaluated. The AWS E309MoL-16 and E316L-17 weld metal was employed as filler metal. Plates of the AISI 444 were welded on ASTM A-516 Gr. 60 plates and submitted to fatigue thermal cycle. Samples were extracted from plates welded and heat treated immersed in heavy crude oil at 300 deg C. Optical microscopy (OM), scanning electron microscopy (SEM) and energy dispersive of X-ray analysis (EDX) were used to characterize the microstructure and the corroded surface. The results show that the AISI 444 stainless steels did not present cracks after the thermal fatigue cycle and the heat treated immerse in heavy crude oil. The electrode AWS E309MoL-16 show better corrosion resistance than the AWS E316L-17. (author)

Effects of Cr2N Precipitation on the Antibacterial Properties of AISI 430 Stainless Steel

Directory of Open Access Journals (Sweden)

Je-Kang Du

2016-03-01

Full Text Available Based on their mechanical properties and good corrosion resistance, some commercial Ni-Cr stainless steels have been widely applied as biomaterials, including the austenitic 304 stainless steel, the austenitic 316 stainless steel, the duplex 2205 stainless steel, and the ferritic 430 stainless steel. In order to reduce the occurrence of infections resulting from biomaterial implants, instruments, and medical devices, Cu2+ and Ag2+ ions have been added onto biomaterials for increasing the antibacterial properties, but they are known to damage biofilm. The occurrence of nanoparticles can also improve the antibacterial properties of biomaterials through various methods. In this study, we used Escherichia coli and analyzed the microstructures of American Iron and Steel Institute (AISI 430 stainless steel with a 0.18 mass % N alloy element. During a lower temperature aging, the microstructure of the as-quenched specimen is essentially a ferrite and martensite duplex matrix with some Cr2N precipitates formed. Additionally, the antibacterial properties of the alloy for E. coli ranged from 3% to 60%, consistent with the presence of Cr2N precipitates. When aged at a lower temperature, which resulted in nano-Cr2N precipitation, the specimen possessed the highest antibacterial activity.

Magnetic sublattices in Np{sub 2}Co{sub 17} and Np{sub 2}Ni{sub 17}

Energy Technology Data Exchange (ETDEWEB)

Colineau, E., E-mail: eric.colineau@ec.europa.eu; Hen, A. [Institute for Transuranium Elements (ITU), European Commission, Joint Research Centre (JRC) (Germany); Sanchez, J.-P. [CEA, INAC-SPSMS (France); Griveau, J.-C.; Magnani, N.; Eloirdi, R. [Institute for Transuranium Elements (ITU), European Commission, Joint Research Centre (JRC) (Germany); Halevy, I. [Ben Gurion University, Nuclear Engineering Department (Israel); Gaczyński, P. [Institute for Transuranium Elements (ITU), European Commission, Joint Research Centre (JRC) (Germany); Orion, I. [Ben Gurion University, Nuclear Engineering Department (Israel); Shick, A. B. [Institute of Physics, ASCR (Czech Republic); Caciuffo, R. [Institute for Transuranium Elements (ITU), European Commission, Joint Research Centre (JRC) (Germany)

2016-12-15

Rare-earth-based compounds R{sub 2}T{sub 17} (R=Rare earth; T=Transition metal) have been extensively studied and developed for applications as permanent magnets. The actinide-based analogues, however, are much less documented and we report here about the magnetic properties of Np{sub 2}Co{sub 17} and Np{sub 2}Ni{sub 17}, as inferred from {sup 237}Np Mössbauer spectroscopy, the best resonance in actinides, and specific heat.

ANALYSIS OF CUTTING FORCE AND CHIP MORPHOLOGY DURING HARD TURNING OF AISI D2 STEEL

Directory of Open Access Journals (Sweden)

X. M. ANTHONY

2015-03-01

Full Text Available In this research work AISI D2 tool steel at a hardness of 55 HRC is being used for experimental investigation. Cutting speed, feed rate and depth of cut are the cutting parameters considered for the experimentation along with tool geometry namely, nose radius, clearance angle and rake angle. Three different cutting tool materials are used for experimentation namely multicoated carbide, cermet and ceramic inserts. The cutting force generated during the machining process is being measured using Kistler dynamometer and recorded for further evaluation. The chips produced during the machining process for every experimental trail is also collected for understanding the chip morphology. Based on the experimental data collected Analysis of Variance (ANOVA was conducted to understand the influence of all cutting parameters and tool geometry on cutting force.

Évolution de la surface de plasticité sous chargement biaxial dans un acier inoxydable duplex

Science.gov (United States)

Aubin, V.; Quaegebeur, P.; Degallaix, S.

2002-12-01

Nous proposons une méthodologie de mesure automatique de la surface de plasticité pendant des chargements cycliques biaxiaux. La surface de plasticité est mesurée de manière discrète avec un faible offset de déformation plastique (2 10^{-5}) et des paramètres de mesure optimisés. La méthode est appliquée à un acier inoxydable duplex soumis à un trajet de chargement non-proportionnel. Les résultats montrent une distorsion et une translation de la surface de plasticité sans changement de taille. La méthode présentée permet également de vérifier la normalité de la vitesse d'écoulement plastique par rapport à la surface de plasticité.

NEUROD2 and NEUROD3 genes map to human chromosomes 17q12 and 5q23-q31 and mouse chromosomes 11 and 13, respectively

Energy Technology Data Exchange (ETDEWEB)

Tamimi, R.M.; Montgomery-Dyer, K.; Tapscott, S.J. [Fred Hutchinson Cancer Research Center, Seattle, WA (United States)] [and others

1997-03-01

NEUROD2 and NEUROD3 are transcription factors involved in neurogenesis that are related to the basic helix-loop-helix protein NEUROD. NEUROD2 maps to human chromosome 17q12 and mouse chromosome 11. NEUROD3 maps to human chromosome 5q23-q31 and mouse chromosome 13. 16 refs., 2 figs.

The influence of heat treatment and process parameters optimization on hardness and corrosion properties of laser alloyed X12CrNiMo steel

CSIR Research Space (South Africa)

Popoola, API

2016-10-01

Full Text Available Martensitic stainless steels are used in the production of steam turbine blades but their application is limited due to low hardness and poor corrosion resistance. Laser surface alloying and heat treatment of X12CrNiMo Martensitic stainless steel...

A study on the microstructure and mechanical properties of AISI D2 tool steel modified by niobium

Energy Technology Data Exchange (ETDEWEB)

Hamidzadeh, M.A.; Meratian, M. [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Mohammadi Zahrani, M., E-mail: iut.mohammadi@gmail.com [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

2012-10-30

The microstructure and mechanical properties of AISI D2 tool steel with up to 1.5 wt% niobium additions were investigated. The microstructural evolutions were characterized by means of optical microscopy and scanning electron microscopy techniques. Mechanical properties of the samples were measured using tensile testing, hardness measurements and Charpy impact test. The results indicated that modification of the microstructure was effectively achieved through the addition of 1.5 wt% of niobium, which refined the prior-austenite grains and decreased the volume fraction of eutectic carbides. Also, the eutectic carbide network tended to break thereby forming blocky and ribbon-like morphologies in the eutectic structures. The ductility and impact toughness of the niobium-contained steels were increased considerably and reached to about 5.8% and 15 J/cm{sup 2}, respectively. Generally, the results of this study suggest that niobium can be used as an alloying element to significantly enhance the ductility and impact toughness of D2 tool steel without affecting the hardness.

A study on the microstructure and mechanical properties of AISI D2 tool steel modified by niobium

International Nuclear Information System (INIS)

Hamidzadeh, M.A.; Meratian, M.; Mohammadi Zahrani, M.

2012-01-01

The microstructure and mechanical properties of AISI D2 tool steel with up to 1.5 wt% niobium additions were investigated. The microstructural evolutions were characterized by means of optical microscopy and scanning electron microscopy techniques. Mechanical properties of the samples were measured using tensile testing, hardness measurements and Charpy impact test. The results indicated that modification of the microstructure was effectively achieved through the addition of 1.5 wt% of niobium, which refined the prior-austenite grains and decreased the volume fraction of eutectic carbides. Also, the eutectic carbide network tended to break thereby forming blocky and ribbon-like morphologies in the eutectic structures. The ductility and impact toughness of the niobium-contained steels were increased considerably and reached to about 5.8% and 15 J/cm 2 , respectively. Generally, the results of this study suggest that niobium can be used as an alloying element to significantly enhance the ductility and impact toughness of D2 tool steel without affecting the hardness.

Hardness of AISI type 410 martensitic steels after high temperature irradiation via nanoindentation

Science.gov (United States)

Waseem, Owais Ahmed; Jeong, Jong-Ryul; Park, Byong-Guk; Maeng, Cheol-Soo; Lee, Myoung-Goo; Ryu, Ho Jin

2017-11-01

The hardness of irradiated AISI type 410 martensitic steel, which is utilized in structural and magnetic components of nuclear power plants, is investigated in this study. Proton irradiation of AISI type 410 martensitic steel samples was carried out by exposing the samples to 3 MeV protons up to a 1.0 × 1017 p/cm2 fluence level at a representative nuclear reactor coolant temperature of 350 °C. The assessment of deleterious effects of irradiation on the micro-structure and mechanical behavior of the AISI type 410 martensitic steel samples via transmission electron microscopy-energy dispersive spectroscopy and cross-sectional nano-indentation showed no significant variation in the microscopic or mechanical characteristics. These results ensure the integrity of the structural and magnetic components of nuclear reactors made of AISI type 410 martensitic steel under high-temperature irradiation damage levels up to approximately 5.2 × 10-3 dpa.

11.72-sq cm Active-Area Wafer Interconnected PiN Diode Pulsed at 64 kA Dissipates 382 J and Exhibits an Action of 1.7 MA(sup 2)-s

Science.gov (United States)

2012-01-30

calculated action exceeded 1.7 MA2 -s. Preliminary efforts on high voltage diode interconnection have produced quarter wafer interconnected PiN...was packaged in a “hockey-puck” configuration and pulsed to 64 kA, dissipating 382 J with a calculated action exceeding 1.7 MA2 -s. II. FULL...epitaxial layers are utilized. 11.72-cm2 Active-area Wafer Interconnected PiN Diode pulsed at 64 kA dissipates 382 J and exhibits an action of 1.7 MA2 -s

11 CFR 102.11 - Petty cash fund (2 U.S.C. 432(h)(2)).

Science.gov (United States)

2010-01-01

... 11 Federal Elections 1 2010-01-01 2010-01-01 false Petty cash fund (2 U.S.C. 432(h)(2)). 102.11 Section 102.11 Federal Elections FEDERAL ELECTION COMMISSION GENERAL REGISTRATION, ORGANIZATION, AND... and Congressional district) sought by such candidate. ...

Refining the microstructure of an AISI M2 tool steel by high-energy milling

International Nuclear Information System (INIS)

Postiglioni, R.V.; Alamino, A.E; Vurobi Junior, S.

2009-01-01

Samples of AISI M2 steel were produced by high-energy milling from chips of machining in Spex high energy mill, compaction and sintering of the powder obtained. The powder was analyzed by X-ray diffraction, and then compressed in discs of 8mm in diameter. The specimens have sintering at 1200 deg C for 1 hour under vacuum atmosphere, followed by annealing, quenching and tempering for 1 hour at 315 deg C and 540°C. Along with each disc, a sample of as-received steel was subjected to the same heat treatments to compare the final microstructure. After standard metallographic preparation, samples were etched with Beraha's reagent, characterized by optical microscopy, quantitative metallography, scanning electron microscopy with micro analysis and mapping by EDS, besides Vickers hardness. The steel produced by high-energy milling presented more refined carbide and better distribution in the microstructure. There was also reduction in the size of prior austenitic grains. (author)

Stoichiometric titanium dioxide ion implantation in AISI 304 stainless steel for corrosion protection

Science.gov (United States)

Hartwig, A.; Decker, M.; Klein, O.; Karl, H.

2015-12-01

The aim of this study is to evaluate the applicability of highly chemically inert titanium dioxide synthesized by ion beam implantation for corrosion protection of AISI 304 stainless steel in sodium chloride solution. More specifically, the prevention of galvanic corrosion between carbon-fiber reinforced plastic (CFRP) and AISI 304 was investigated. Corrosion performance of TiO2 implanted AISI 304 - examined for different implantation and annealing parameters - is strongly influenced by implantation fluence. Experimental results show that a fluence of 5 × 1016 cm-2 (Ti+) and 1 × 1017 cm-2 (O+) is sufficient to prevent pitting corrosion significantly, while galvanic corrosion with CFRP can already be noticeably reduced by an implantation fluence of 5 × 1015 cm-2 (Ti+) and 1 × 1016 cm-2 (O+). Surface roughness, implantation energy and annealing at 200 °C and 400 °C show only little influence on the corrosion behavior. TEM analysis indicates the existence of stoichiometric TiO2 inside the steel matrix for medium fluences and the formation of a separated metal oxide layer for high fluences.

Effect of shot peening on the residual stress and mechanical behaviour of low-temperature and high-temperature annealed martensitic gear steel 18CrNiMo7-6

DEFF Research Database (Denmark)

Yang, R.; Zhang, X.; Mallipeddi, D.

2017-01-01

A martensitic gear steel (18CrNiMo7-6) was annealed at 180 degrees C for 2h and at similar to 750 degrees C for 1h to design two different starting microstructures for shot peening. One maintains the original as-transformed martensite while the other contains irregular-shaped sorbite together...... with ferrite. These two materials were shot peened using two different peening conditions. The softer sorbite + ferrite microstructure was shot peened using 0.6 mm conditioned cut steel shots at an average speed of 25 m/s in a conventional shot peening machine, while the harder tempered martensite steel...

Wear resistance of Fe-Nb-Cr-W, Nb, AISI 1020 and AISI 420 coatings produced by thermal spray wire arc; Resistencia al desgaste de recubrimientos Fe-Nb-Cr-W, Nb, AISI 1020 y AISI 420 producidos por proyeccion termica por arco electrico

Energy Technology Data Exchange (ETDEWEB)

Lopez-Covaleda, E. A.; Mercado-Veladia, J. L.; Olaya-Florez, J. J.

2013-07-01

The commercial materials 140MXC (with iron, tungsten, chrome, niobium), 530AS (AISI 1015 steel) and 560AS (AISI 420 steel) on AISI 4340 steel were deposited using thermal spray with arc. The aim of work was to evaluate the best strategy abrasive wear resistance of the system coating-substrate using the following combinations: (1) homogeneous coatings and (2) coatings depositing simultaneously 140MXC + 530AS and 140MXC + 560AS. The coatings microstructure was characterized using Optical microscopy, Scanning electron microscopy and Laser con focal microscopy. The wear resistance was evaluated through dry sand rubber wheel test (DSRW). We found that the wear resistance depends on the quantity of defects and the mechanical properties like hardness. For example, the softer coatings have the biggest wear rates and the failure mode was characterized by plastic deformation caused by particles indentation, and the other hand the failure mode at the harder materials was grooving. The details and wear mechanism of the coatings produced are described in this investigation. (Author)

Mapping 22q11.2 Gene Dosage Effects on Brain Morphometry.

Science.gov (United States)

Lin, Amy; Ching, Christopher R K; Vajdi, Ariana; Sun, Daqiang; Jonas, Rachel K; Jalbrzikowski, Maria; Kushan-Wells, Leila; Pacheco Hansen, Laura; Krikorian, Emma; Gutman, Boris; Dokoru, Deepika; Helleman, Gerhard; Thompson, Paul M; Bearden, Carrie E

2017-06-28

, reciprocal genomic imbalances at this locus confer some of the highest known genetic risks for developmental neuropsychiatric disorders. Here we provide the first evidence that brain morphology differs meaningfully as a function of reciprocal genomic variation at the 22q11.2 locus. Cortical thickness and surface area were affected in opposite directions with more widespread effects of gene dosage on cortical surface area. Copyright © 2017 the authors 0270-6474/17/376184-17$15.00/0.

48 CFR 17.105-2 - Objectives.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Objectives. 17.105-2 Section 17.105-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS... contracts. (d) Substantial continuity of production or performance, thus avoiding annual startup costs...

Resistência à corrosão de junta dissimilar soldada pelo processo TIG composta pelos aços inoxidáveis AISI 316L e AISI 444

Directory of Open Access Journals (Sweden)

Luis Henrique Guilherme

2014-03-01

Full Text Available O aço inoxidável AISI 444 tornou-se uma opção para substituir a liga AISI 316L devido ao seu menor custo e satisfatória resistência à corrosão. Entretanto, o uso da liga AISI 444 no feixe tubular de trocadores de calor acarreta na soldagem de uma junta dissimilar. O presente estudo teve por objetivo avaliar a resistência à corrosão da junta tubo-espelho soldada pelo processo TIG composta pelas ligas AISI 316L e AISI 444. A manufatura das amostras consistiu em replicar o projeto da junta tubo-espelho de trocadores de calor. Realizou-se em juntas soldadas ensaios de sensitização, perda de massa por imersão desde a temperatura ambiente até 90 ºC, e ensaios eletroquímicos de polarização potenciodinâmica nos eletrólitos 0,5 mol/L de HCl e 0,5 mol/L de H2SO4. Os resultados mostraram que a junta dissimilar sofreu corrosão galvânica com maior degradação na zona afetada pelo calor (ZAC do tubo AISI 444. Porém, os mecanismos de corrosão localizada (pite e intergranular demonstraram ser mais ativos para a liga AISI 316L. Conclui-se que a junta dissimilar apresentou melhor resistência à corrosão do que a junta soldada composta unicamente pela liga AISI 316L em temperaturas de até 70 ºC, conforme as condições observadas neste trabalho.

The effect of plasma arc process parameters on the properties of dissimilar AISI 1040/AISI 304 steel plate welds

Energy Technology Data Exchange (ETDEWEB)

Kilic, Musa; Kirik, Ihsan; Orhan, Nuri [Firat Univ., Elazig (Turkey); Celik, Ferkan [Science Industry and Technology Ministry of Turkey (Turkey)

2012-11-01

In this study, 10 mm thick AISI 1040 and AISI 304 steel plates were welded in the butt position without pretreatment by plasma transferred arc (PTA) welding technique. Therefore, mechanical behaviour, microstructure, penetration depth and length were investigated. After welding, microstructural changes in the interface regions of the welded specimens were examined by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). Micro-hardness as well as V-notch Charpy tests were performed to determine the mechanical properties of the welds. The influence of the welding parameters on the dimension and shape of the joints has been found out. From the results, it was derived that with the parameters used, a partly keyhole weld bead formed with a penetration depth of 10 mm and a width of 11 mm in butt position. (orig.)

17 CFR 39.2 - Exemption.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Exemption. 39.2 Section 39.2 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION DERIVATIVES CLEARING ORGANIZATIONS § 39.2 Exemption. A derivatives clearing organization and the clearing of agreements, contracts and...

17 CFR 37.2 - Exemption.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Exemption. 37.2 Section 37.2 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION DERIVATIVES TRANSACTION EXECUTION FACILITIES § 37.2 Exemption. Contracts, agreements or transactions traded on a derivatives transaction...

Soft-martensitic stainless Cr-Ni-Mo steel for turbine rotors in geothermic power stations

International Nuclear Information System (INIS)

Schonfeld, K.; Potthast, E.

1986-01-01

Steel Grade X5 Cr-Ni-Mo 12 6 containing 0.05% carbon, 12% chromium, 6% nickel, and 1.50% molybdenum is an advantageous material for turbine rotors in geothermic power stations because of its excellent strength and toughness properties in combination with good erosion and corrosion resistance. In terms of the phase diagram, this soft-martensitic steel has its place at the martensite/austenite/ferrite interface. Therefore, its chemical composition must be chosen so as to have a completely martensitic structure after hardening. The manufacture of and the mechanical properties of a turbine rotor 1200 mm in diameter by 5600 mm in length with a finished weight of approximately 21.5 tons are described in detail

17 CFR 202.11 - Public Company Accounting Oversight Board budget approval process.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Public Company Accounting Oversight Board budget approval process. 202.11 Section 202.11 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION INFORMAL AND OTHER PROCEDURES § 202.11 Public Company Accounting Oversight...

Development of Nb2O5|Cu composite as AISI 1020 steel thermal spray coating for protection against corrosion by soil in buried structures

International Nuclear Information System (INIS)

Regis Junior, Oscar; Silva, Jose Maurilio da; Portella, Kleber Franke; Paredes, Ramon Sigifredo Cortes

2012-01-01

An Nb 2 O|Cu corrosion-resistant coating was developed and applied onto AISI 1020 steel substrate by Powder Flame Spray. A galvanostatic electrochemical technique was employed, with and without ohmic drop, in four different soils (two corrosively aggressive and two less aggressive). Behavior of coatings in different soils was compared using a cathodic hydrogen reduction reaction (equilibrium potential, overvoltage and exchange current density) focusing on the effect of ohmic drop. Results allow recommendation of Nb 2 O 5 |Cu composite for use in buried structure protection. (author)

Low temperature plasma carburizing of AISI 316L austenitic stainless steel and AISI F51 duplex stainless steel

OpenAIRE

Pinedo,Carlos Eduardo; Tschiptschin,André Paulo

2013-01-01

In this work an austenitic AISI 316L and a duplex AISI F51 (EN 1.4462) stainless steel were DC-Plasma carburized at 480ºC, using CH4 as carbon carrier gas. For the austenitic AISI 316L stainless steel, low temperature plasma carburizing induced a strong carbon supersaturation in the austenitic lattice and the formation of carbon expanded austenite (γC) without any precipitation of carbides. The hardness of the carburized AISI 316L steel reached a maximum of 1000 HV due to ∼13 at% c...

Low temperature plasma carburizing of AISI 316L austenitic stainless steel and AISI F51 duplex stainless steel

OpenAIRE

Pinedo, Carlos Eduardo; Tschiptschin, André Paulo

2013-01-01

In this work an austenitic AISI 316L and a duplex AISI F51 (EN 1.4462) stainless steel were DC-Plasma carburized at 480ºC, using CH4 as carbon carrier gas. For the austenitic AISI 316L stainless steel, low temperature plasma carburizing induced a strong carbon supersaturation in the austenitic lattice and the formation of carbon expanded austenite (γC) without any precipitation of carbides. The hardness of the carburized AISI 316L steel reached a maximum of 1000 HV due to ∼13 at% carbon super...

Effect of electrical discharge machining on surface characteristics and machining damage of AISI D2 tool steel

International Nuclear Information System (INIS)

Guu, Y.H.; Hocheng, H.; Chou, C.Y.; Deng, C.S.

2003-01-01

In this work the electrical discharge machining (EDM) of AISI D2 tool steel was investigated. The surface characteristics and machining damage caused by EDM were studied in terms of machining parameters. Based on the experimental data, an empirical model of the tool steel was also proposed. A new damage variable was used to study the EDM damage. The workpiece surface and re-solidified layers were examined by a scanning electron microscopy. Surface roughness was determined with a surface profilometer. The residual stress acting on the EDM specimen was measured by the X-ray diffraction technique. Experimental results indicate that the thickness of the recast layer, and surface roughness are proportional to the power input. The EDM process introduces tensile residual stress on the machined surface. The EDM damage leads to strength degradation

A constitutional translocation t(1;17(p36.2;q11.2 in a neuroblastoma patient disrupts the human NBPF1 and ACCN1 genes.

Directory of Open Access Journals (Sweden)

Karl Vandepoele

Full Text Available The human 1p36 region is deleted in many different types of tumors, and so it probably harbors one or more tumor suppressor genes. In a Belgian neuroblastoma patient, a constitutional balanced translocation t(1;17(p36.2;q11.2 may have led to the development of the tumor by disrupting or activating a gene. Here, we report the cloning of both translocation breakpoints and the identification of a novel gene that is disrupted by this translocation. This gene, named NBPF1 for Neuroblastoma BreakPoint Family member 1, belongs to a recently described gene family encoding highly similar proteins, the functions of which are unknown. The translocation truncates NBPF1 and gives rise to two chimeric transcripts of NBPF1 sequences fused to sequences derived from chromosome 17. On chromosome 17, the translocation disrupts one of the isoforms of ACCN1, a potential glioma tumor suppressor gene. Expression of the NBPF family in neuroblastoma cell lines is highly variable, but it is decreased in cell lines that have a deletion of chromosome 1p. More importantly, expression profiling of the NBPF1 gene showed that its expression is significantly lower in cell lines with heterozygous NBPF1 loss than in cell lines with a normal 1p chromosome. Meta-analysis of the expression of NBPF and ACCN1 in neuroblastoma tumors indicates a role for the NBPF genes and for ACCN1 in tumor aggressiveness. Additionally, DLD1 cells with inducible NBPF1 expression showed a marked decrease of clonal growth in a soft agar assay. The disruption of both NBPF1 and ACCN1 genes in this neuroblastoma patient indicates that these genes might suppress development of neuroblastoma and possibly other tumor types.

Nitriding the influence of plasma in resistance to wear micro abrasive tool steel AISI D2

International Nuclear Information System (INIS)

Gobbi, Vagner Joao; Gobb, Silvio Jose; Silva, Cosme Roberto Moreira da

2010-01-01

This work studies the influence of time of treatment in the formation of nitride layer of AISI D2 tool steel and the resistance to micro-abrasive wear from the technique of nitriding in plasma. The samples were nitrides at 400 ° C with a pressure of 4.5 mbar (450 Pa) and using a gas mixture of 80% vol.H2 and 20% vol.N2. The times of treatment were: 30, 60, 120, 180 and 360 minutes. The properties of the layers in the samples obtained nitrides were assessed by surface microhardness, profiles of microhardness, metallography analysis, X-ray diffraction and test for resistance to micro-abrasive wear. The best results for nitriding to 400 deg C, was obtained with the time of treatment of 360 minutes. In this case the increase in surface hardness was 94.6% and resistance to micro-abrasive wear of 15%. This increase in hardness may be associated with high concentration of nitrogen in the crystalline network of iron-α and additional training of nitrides. Low temperature of nitriding reduces between grain fragility to reduce the likelihood of precipitation of nitrides in a continuous manner in the austenite grain boundaries and the absence of previous ε'+ γ phases. (author)

Electric dipole f values for Fe II J=9/2->11/2^o transitions

Science.gov (United States)

Beck, Donald R.

2007-06-01

Relativistic configuration-interaction f values have been obtained for all transitions between the lowest 17 J=9/2 and the lowest 27 J=11/2^o levels. The 35 f values >0.01 have an average gauge agreement of 3.6% and generally agree well with the semi-empirical results of Raassen ootnotetextA. J. J. Raassen, ftp://ftp.wins.uva.nl/pub/orth/iron/FeII.E1 (1999).. The near degeneracy of many of the odd levels requires the introduction of small semi-empirical energy shifts ootnotetextD. R. Beck, Phys. Scr. 71, 447 (2005).. A systematic way of estimating radial convergence is discussed.

Screening for strains with 11α-hydroxylase activity for 17α-hydroxy progesterone biotransformation.

Science.gov (United States)

Gao, Qian; Qiao, Yuqian; Shen, Yanbing; Wang, Min; Wang, Xibo; Liu, Yang

2017-08-01

Various corticosteroids are prepared by using 11α,17α-diOH-progesterone (11α,17α-diOH-PROG) as an important intermediate and raw material. Hence, strains that can improve the yields of 11α,17α-diOH-PROG should be screened. Cunninghamella elegans CICC40250 was singled out from five common 11α hydroxylation strains. The reaction parameters of 11α,17α-diOH-PROG production were also investigated. C. elegans CICC40250 could efficiently catalyze the hydroxylation of 17α-hydroxy progesterone (17α-OH-PROG) at C-11α position. This strain could also effectively convert 11α,17α-diOH-PROG at high substrate concentrations (up to 30g/L). After the coenzyme precursor glucose was added, the rate of 11α,17α-diOH-PROG formation reached 84.2%, which was 11.4% higher than that of the control group. Our study established a simple and feasible mechanism to increase 11α,17α-diOH-PROG production levels. This mechanism involves C. elegans CICC40250 that can be efficiently applied to induce the biotransformation of 17α-OH-PROG with a hydroxylation biocatalytic ability. Copyright © 2017. Published by Elsevier Inc.

Microstructure and mechanical properties of friction welded AISI 1040/AISI 304L steels before and after electrochemical corrosion

Energy Technology Data Exchange (ETDEWEB)

Sarsilmaz, Furkan [Firat Univ., Elazig (Turkey). Dept. of Mechatronics Engineering; Kirik, Ihsan [Batman Univ. (Turkey); Ozdemir, Niyazi [Firat Univ., Elazig (Turkey)

2018-03-01

The aim of the present study is to investigate the effect of welding parameters both on the electrochemical corrosion behavior and tensile strength of pre- and post-electrochemical corrosion of friction welded dissimilar steels. The microstructural changes of AISI 1040/AISI 304L friction welded couples and also parent materials were analyzed by using scanning electron microscopy. The electrochemical behaviors of AISI1040/AISI304L joints were comparatively investigated by potentiodynamic polarization curve test and by electrochemical impedance spectra. Moreover, tensile strength experiments were carried out determining the behavior of friction welded joints of pre- and post-electrochemical corrosion and results indicated that the maximum tensile test value of the dissimilar welded pre-electrochemical corrosion was higher than those of post-electrochemical corrosion and was also very close to AISI 1040 parent material value.

Study of residual stresses generated in machining of AISI 4340 steel; Estudo das tensoes residuais geradas na usinagem de aco AISI 4340

Energy Technology Data Exchange (ETDEWEB)

Reis, W.P. dos; Fonseca, M.P. Cindra; Serrao, L.F.; Chuvas, T.C.; Oliveira, L.C., E-mail: mcindra@vm.uff.b [Universidade Federal Fluminense (PGMEC/UFF), Niteroi, RJ (Brazil). Dept. de Engenharia Mecanica

2010-07-01

Among the mechanical construction steels, AISI 4340 has good harden ability, while combining high strength with toughness and good fatigue strength, making it excellent for application in the metalworking industry, where it can work at different levels and types of requests. Residual stresses are generated in almost all processes of mechanical manufacturing. In this study, the residual stresses generated in different machining processes and heat treatment hardening of AISI 4340 were analyzed by X-ray diffraction, by the sen{sup 2} {psi} method, using Cr{kappa}{beta} radiation and compared. All samples, except for turned and cut by EDM, presented compressive residual stresses in the surface with various magnitudes. (author)

19 CFR 11.2 - Manufactured tobacco.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Manufactured tobacco. 11.2 Section 11.2 Customs... PACKING AND STAMPING; MARKING Packing and Stamping § 11.2 Manufactured tobacco. (a) If the invoice and entry presented for manufactured tobacco specify all the information necessary for prompt determination...

Crack Arrest Toughness of Two High Strength Steels (AISI 4140 and AISI 4340)

Science.gov (United States)

Ripling, E. J.; Mulherin, J. H.; Crosley, P. B.

1982-04-01

The crack initiation toughness ( K c ) and crack arrest toughness ( K a ) of AISI 4140 and AISI 4340 steel were measured over a range of yield strengths from 965 to 1240 MPa, and a range of test temperatures from -53 to +74°C. Emphasis was placed on K a testing since these values are thought to represent the minimum toughness of the steel as a function of loading rate. At the same yield strengths and test temperatures, K a for the AISI 4340 was about twice as high as it was for the AISI 4140. In addition, the K a values showed a more pronounced transition temperature than the K c values, when the data were plotted as a function of test temperature. The transition appeared to be associated with a change in fracture mechanism from cleavage to dimpled rupture as the test temperature was increased. The occurrence of a “pop-in” behavior at supertransition temperatures has not been found in lower strength steels, and its evaluation in these high strength steels was possible only because they are not especially tough at their supertransition temperatures. There is an upper toughness limit at which pop-in will not occur, and this was found for the AISI 4340 steel when it was tempered to its lowest yield strength (965 MPa). All the crack arrest data were identified as plane strain values, while only about one-half of the initiation values could be classified this way.

Acoustic Emission Methodology to Evaluate the Fracture Toughness in Heat Treated AISI D2 Tool Steel

Science.gov (United States)

Mostafavi, Sajad; Fotouhi, Mohamad; Motasemi, Abed; Ahmadi, Mehdi; Sindi, Cevat Teymuri

2012-10-01

In this article, fracture toughness behavior of tool steel was investigated using Acoustic Emission (AE) monitoring. Fracture toughness ( K IC) values of a specific tool steel was determined by applying various approaches based on conventional AE parameters, such as Acoustic Emission Cumulative Count (AECC), Acoustic Emission Energy Rate (AEER), and the combination of mechanical characteristics and AE information called sentry function. The critical fracture toughness values during crack propagation were achieved by means of relationship between the integral of the sentry function and cumulative fracture toughness (KICUM). Specimens were selected from AISI D2 cold-work tool steel and were heat treated at four different tempering conditions (300, 450, 525, and 575 °C). The results achieved through AE approaches were then compared with a methodology proposed by compact specimen testing according to ASTM standard E399. It was concluded that AE information was an efficient method to investigate fracture characteristics.

Determining Ms temperature on a AISI D2 cold work tool steel using magnetic Barkhausen noise

Energy Technology Data Exchange (ETDEWEB)

Huallpa, Edgar Apaza, E-mail: gared1@gmail.com [Escola Politécnica da Universidade de São Paulo, Av. Prof. Mello Moraes 2463, 05508-030 SP (Brazil); Sánchez, J. Capó, E-mail: jcapo@usp.br [Departamento de Física, Facultad de Ciencias Naturales, Universidad de Oriente, Av. Patricio Lumumba s/n 90500, Santiago de Cuba (Cuba); Padovese, L.R., E-mail: lrpadove@usp.br [Escola Politécnica da Universidade de São Paulo, Av. Prof. Mello Moraes 2463, 05508-030 SP (Brazil); Goldenstein, Hélio, E-mail: hgoldens@usp.br [Escola Politécnica da Universidade de São Paulo, Av. Prof. Mello Moraes 2463, 05508-030 SP (Brazil)

2013-11-15

Highlights: ► MBN was used to follow the martensite transformation in a tool steel. ► The results were compared with resistivity experiments. ► The Ms was estimated with Andrews equation coupled to ThermoCalc calculations. The experimental results showed good agreement. -- Abstract: The use of Magnetic Barkhausen Noise (MBN) as a experimental method for measuring the martensite start (Ms) temperature was explored, using as model system a cold-work tool steel (AISI D2) austenitized at a very high temperature (1473 K), so as to transform in sub-zero temperatures. The progress of the transformation was also followed with electrical resistance measurements, optical microscopy and scanning electron microscopy. Both MBN and resistivity measurements showed a change near 230 K during cooling, corresponding to the Ms temperature, as compared with 245 K, estimated with Andrews empirical equation applied to the austenite composition calculated using ThermoCalc.

29 CFR 2.11 - General principles.

Science.gov (United States)

2010-07-01

... 29 Labor 1 2010-07-01 2010-07-01 true General principles. 2.11 Section 2.11 Labor Office of the Secretary of Labor GENERAL REGULATIONS Audiovisual Coverage of Administrative Hearings § 2.11 General principles. The following general principles will be observed in granting or denying requests for permission...

Electroexcitation of the Roper resonance for 1.7 < Q**2 < 4.5 -GeV2 in vec-ep ---> en pi+

Energy Technology Data Exchange (ETDEWEB)

Aznauryan, Inna; Burkert, Volker; Kim, Wooyoung; Park, Kil; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Ambrozewicz, Pawel; Anghinolfi, Marco; Asryan, Gegham; Avagyan, Harutyun; Bagdasaryan, H.; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Barrow, Steve; Batourine, V.; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bonner, Billy; Bookwalter, Craig; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, Wilbert; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Casey, Liam; Cazes, Antoine; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Cords, Dieter; Corvisiero, Pietro; Crabb, Donald; Crede, Volker; Cummings, John; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dhamija, Seema; Dharmawardane, Kahanawita; Dhuga, Kalvir; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Donnelly, J.; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Feldman, Gerald; Feuerbach, Robert; Forest, Tony; Fradi, Ahmed; Funsten, Herbert; Gabrielyan, Marianna; Garcon, Michel; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gohn, Wesley; Golovach, Evgeny; Gonenc, Atilla; Gordon, Christopher; Gothe, Ralf; Graham, L.; Griffioen, Keith; Guidal, Michel; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hafnaoui, Khadija; Hakobyan, Hayk; Hakobyan, Rafael; Hanretty, Charles; Hardie, John; Hassall, Neil; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Keller, Dustin; Kellie, James; Khandaker, Mahbubul; Kim, Kui; Klein, Andreas; Klein, Andreas; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, Dave; Lee, T.; Lima, Ana; Livingston, Kenneth; Lu, Haiyun; Lukashin, Konstantin; MacCormick, Marion; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Morand, Ludyvine; Moreno, Brahim; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; O' Rielly, Grant; Osipenko, Mikhail; Ostrovidov, Alexander; Park, S.; Pasyuk, Evgueni; Paterson, Craig; Anefalos Pereira, S.; Philips, Sasha; Pierce, Jerome; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Polli, Ermanno; Popa, Iulian; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Prok, Yelena; Protopopescu, Dan; Qin, Liming; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Rowntree, David; Rubin, Philip; Sabatie, Franck; Saini, Mukesh; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schott, Diane; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shaw, J.; Shvedunov, Nikolay; Skabelin, Alexander; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinskiy, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham

2008-10-01

DOI: http://dx.doi.org/10.1103/PhysRevC.78.045209
The helicity amplitudes of the electroexcitation of the Roper resonance are extracted for 1.7 < Q2 < 4.5 GeV2 from recent high precision JLab-CLAS cross section and longitudinally polarized beam asymmetry data for pi+ electroproduction on protons at W=1.15-1.69 GeV. The analysis is made using two approaches, dispersion relations and a unitary isobar model, which give consistent results. It is found that the transverse helicity amplitude A_{1/2} for the gamma* p -> N(1440)P11 transition, which is large and negative at Q2=0, becomes large and positive at Q2 ~ 2 GeV2, and then drops slowly with Q2. The longitudinal helicity amplitude S_{1/2}, which was previously found from CLAS ep -> eppi0,enpi+ data to be large and positive at Q2=0.4,0.65 GeV2, drops with Q2. Available model predictions for gamma* p -> N(1440)P11 allow us to conclude that these results provide strong evidence in favor of N(1440)P11 as a first radial excitation of

Influence of enzymatic reactions on the electrochemical behavior of EN X2CrNiMo17-11-2 (AISI 316L) stainless steel in bio-corrosion: role of interfacial processes on the modification of the passive layer

International Nuclear Information System (INIS)

Landoulsi, J.

2008-01-01

The outstanding corrosion behavior of stainless steels (SS) results from the presence of thin oxide layer (some nanometers). In non sterile aqueous media, stainless steels may exhibit a non stable behavior resulting from interactions between microbial species and passive film. In fact, microorganisms can be deeply involved in the corrosion processes usually reported as Microbial Influenced Corrosion (MIC). They can induce the initiation or the acceleration of this phenomenon and they do so when organized in bio-films. From the electrochemical point of view, stainless steels showed an increase of the free corrosion potential (Ecorr) attributed to the bio-film settlement. The Eco' ennoblement was broadly reported in seawater and seems to be confirmed in fresh water according to recent findings. A considerable progress in the comprehension of MIC processes was related to the role of extracellular species, essentially enzymes. Many enzymatic reactions occurring in bio-films consist on using oxygen as electron acceptor to generate hydrogen peroxide and related species. The aim of this work is to understand the mechanisms involved in the electrochemical behavior of stainless steel according to an enzymatic approach in medium simulating fresh water. To this end, glucose oxidase was chosen to globalize aerobic activities of bio-films. Electrochemical measurements in situ and surface analysis allow the comprehension of the role and the nature of interfacial processes. Surface characterization was performed with the help of a new quantitative utilization of XPS analysis and AFM. Results show a significant evolution in term of morphology (surface organization), (ii) chemical composition (passive layer, adsorbed organic species) and (iii) chemical reaction (oxidation, dissolution, effect of enzyme). Finally, a new enzymatic system is proposed to mimic specific physicochemical conditions at the SS / bio-film interface, in particular enzymatic generation of oxidant species in diffusion limiting conditions. (author)

Microstructural evolution of a cold work tool steel after pulsed laser remelting

Directory of Open Access Journals (Sweden)

L. Kosec

2012-01-01

Full Text Available The aim of this study is the investigation of micro-structural behaviour of a Mat. No. 1.2379 (EN-X160CrMoV121; AISI D2 cold work tool steel after remelting with a precise pulsed Nd:YAG laser. The investigated steel is one of the most hard to weld tool steels, due to large amount of alloying elements. The analysis was done on single spots remelted with specific laser pulse shape and parameters, assuring crack-less solidification. Re-solidifi ed areas were investigated with microscopy, hardness measurements, X-ray spectroscopy and diffraction method. Laser treatment causes rapid solidifi cation leading into a formation of a fine dendritic microstructures containing high amount of retained austenite causing a significant decrease of hardness.

17 CFR 240.17a-11 - Notification provisions for brokers and dealers.

Science.gov (United States)

2010-04-01

... brokers and dealers. 240.17a-11 Section 240.17a-11 Commodity and Securities Exchanges SECURITIES AND... Stabilizing Activities § 240.17a-11 Notification provisions for brokers and dealers. (a) This section shall apply to every broker or dealer registered with the Commission pursuant to section 15 of the Act. (b)(1...

Microstructures and phase formations in the surface layer of an AISI D2 steel treated with pulsed electron beam

International Nuclear Information System (INIS)

Zou, J.X.; Grosdidier, T.; Zhang, K.M.; Gao, B.; Hao, S.Z.; Dong, C.

2007-01-01

The nanostructures and metastable phase transformations in the surface layer of an AISI D2 steel treated with high current pulsed electron beam (HCPEB) were investigated. The surface structure is marked by two distinct features, i.e. the formation of sub-micrometer fine austenite γ grains (50-150 nm), and the disappearance of carbides via dissolution and crater eruption. The γ phase directly grows from the melt and is retained down to room temperature. Although the cooling rate is as high as 10 7 K/s in our case, the martensitic transformation could completely be suppressed. Such an effect is due to the increased stability of the austenite phase through grain refinement and chemistry modification

36 CFR 2.17 - Aircraft and air delivery.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Aircraft and air delivery. 2.17 Section 2.17 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.17 Aircraft and air delivery. (a) The following are...

17 CFR 232.11 - Definition of terms used in part 232.

Science.gov (United States)

2010-04-01

... effect by a person executing or issuing it. If data are stored in a computer or similar device, any... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Definition of terms used in part 232. 232.11 Section 232.11 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION...

Estimation of embrittlement during aging of AISI 316 stainless steel ...

Indian Academy of Sciences (India)

Unknown

rical relation connecting the aging temperature, aging time and nitrogen ... strength, high tensile strength, are easy to fabricate and ... However, the ferrite is a metastable phase which ... 2. Experimental. 2.1 Materials. Nuclear grade AISI 316 stainless steel plates ( .... fore, it is desirable to develop empirical relations con-.

Vanadium(V-Substitution Reactions of Wells–Dawson-Type Polyoxometalates: From [X2M18O62]6− (X = P, As; M = Mo, W to [X2VM17O62]7−

Directory of Open Access Journals (Sweden)

Tadaharu Ueda

2015-07-01

Full Text Available The formation processes of V(V-substituted polyoxometalates with the Wells–Dawson-type structure were studied by cyclic voltammetry and by 31P NMR and Raman spectroscopy. Generally, the vanadium-substituted heteropolytungstates, [P2VW17O62]7− and [As2VW17O62]7−, were prepared by mixing equimolar amounts of the corresponding lacunary species—[P2W17O61]10− and [As2W17O61]10−—and vanadate. According to the results of various measurements in the present study, the tungsten site in the framework of [P2W18O62]6− and [As2W18O62]6− without defect sites could be substituted with V(V to form the [P2VW17O62]7− and [As2VW17O62]7−, respectively. The order in which the reagents were mixed was observed to be the key factor for the formation of Dawson-type V(V-substituted polyoxometalates. Even when the concentration of each reagent was identical, the final products differed depending on the order of their addition to the reaction mixture. Unlike Wells–Dawson-type heteropolytungstates, the molybdenum sites in the framework of [P2Mo18O62]6− and [As2Mo18O62]6− were substituted with V(V, but formed Keggin-type [PVMo11O40]4− and [AsVMo11O40]4− instead of [P2VMo17O62]7− and [As2VMo17O62]7−, respectively, even though a variety of reaction conditions were used. The formation constant of the [PVMo11O40]4− and [AsVMo11O40]4− was hypothesized to be substantially greater than that of the [P2VMo17O62]7− and [As2VMo17O62]7−.

Machining tools in AISI M2 high-speed steel obtained by spray forming process; Ferramentas de usinagem em aco rapido AISI M2 obtido por conformacao por 'spray'

Energy Technology Data Exchange (ETDEWEB)

Jesus, Edilson Rosa Barbosa de. E-mail: erbjesus@usp.br

2004-07-01

The aim of the present work was the obtention of AISI M2 high-speed steel by spray forming technique and the material evaluation when used as machining tool. The obtained material was hot rolled at 50% and 72% reduction ratios, and from which it was manufactured inserts for machining tests. The performance of inserts made of the spray formed material was compared to inserts obtained from conventional and powder metallurgy (MP) processed materials. The spray formed material was chemical, physical, mechanical and microstructural characterised. For further characterisation, the materials were submitted to machining tests for performance evaluation under real work condition. The results of material characterisation highlight the potential of the spray forming technique, in the obtention of materials with good characteristics and properties. Under the current processing, hot rolling and heat treatments condition, the analysis of the results of the machining tests revealed a very similar behaviour among the tested materials. Proceeding a criterious analysis of the machining results tests, it was verified that the performance presented by the powder metallurgy material (MP) was slight superior, followed by conventional obtained material (MConv), which presented a insignificant advantage over the spray formed and hot rolled (72% reduction ratio) material. The worst result was encountered for the spray forming and hot rolled (50% reduction ratio) material that presented the highest wear values. (author)

Stainless-Steel-Gadolinium Alloys; Alliages Acier Inoxydable-Gadolinium; Splavy iz nerzhaveyushchej stali i gadoliniya; Aleaciones de Acero Inoxidable-Gadolinio

Energy Technology Data Exchange (ETDEWEB)

Copeland, M.; Kato, H. [Albany Metallurgy Research Center, Bureau Of Mines, United States Department of the Interior, Albany, OR (United States)

1964-06-15

Because of the excellent corrosion resistance of stainless steels and the interest in gadolinium as a poison material, alloys of the two compounds were studied.Gadolinium was alloyed with AISE 304-type and chromium-type stainless steels; and then phase relationships, fabricability and properties were studied. The melting points of minor phases in alloys containing low percentages of gadolinium were noted to have a large effect on the structures resulting from equilibrating treatments and fabricability of the steels. When gadolinium was alloyed with the chromium-nickel-type steel, two minor phases, Fe{sub 9}Gd and Ni{sub 7}Gd, were observed to melt at 1080 Degree-Sign C, which limited the heat treatment and fabrication temperatures. Alloys with up to 5 wt.% gadolinium were successfully fabricated, and mechanical and corrosion properties were determined. No changes in the mechanical properties or resistance to hot-water corrosion of the steel were observed on alloying with up to about 3 wt.% gadolinium. Because of fabrication temperature limitations placed on chromium-nickel steels by the melting point of the minor phases, the effects of gadolinium on chromium steels were studied. Only one minor phase that melted at 1320 Degree-Sign C was noted on investigation of the 10 wt. % gadolinium isopleth in the chromium-iron-gadolinium alloy system. This property would enable one to equilibrate and fabricate these gadolinium steels at normally used temperatures. (author) [French] Les auteurs ont etudie des alliages d'acier inoxydable et de gadolinium en raison de l'excellente resistance a la corrosion des aciers inoxydables et de l 'interet que presente le gadolinium comme poison. Ils ont allie du gadolinium a des aciers inoxydables AISI de nuance 304 et des aciers au chrome et ils ont etudie le diagramme des phases, les possibilites de transformation et les proprietes de ces alliages. Dans les alliages d'une faible teneur en gadolinium, les points de fusion des phases

17 CFR 41.2 - Required records.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Required records. 41.2 Section 41.2 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SECURITY FUTURES PRODUCTS General Provisions § 41.2 Required records. A designated contract market or registered derivatives...

Oxidation and corrosion studies of Al-implanted stainless steel AISI 321 using nuclear reaction and electrochemical techniques

International Nuclear Information System (INIS)

Noli, F.; Misaelides, P.; Spathis, P.; Pilakouta, M.; Baumann, H.

1992-01-01

The oxidation of Al-implanted (implantation energy 40 keV, dose 10 16 -10 17 Al ions/cm 2 ) AISI 321 stainless steel samples in air has been studied at temperatures between 450 and 650degC using the 16 O(d,p) 17 O nuclear reaction. The determination of the distribution of the implanted Al atoms has been performed using the resonance at 992 keV of the 27 Al(p,γ) 28 Si nuclear reaction. The determined oxygen profiles indicate that the implantation of 5x10 16 and 10 17 Al ions/cm 2 leads to an improvement of the oxidation resistance of the studied steel samples. The passivation/corrosion behaviour of the Al-implanted steel samples in 0.5M aqueous sulphuric acid solution has also been investigated electrochemically using potentiodynamic and cyclovoltammetric techniques. The passivation potential values and the repassivation moving to more positive values indicate an improvement of the corrosion resistance of the Al-implanted steel samples. (orig.)

Erosion of heat-treated AISI 4140 steel

Energy Technology Data Exchange (ETDEWEB)

Goretta, K.C. (Materials and Components Tech. Div., Argonne National Lab., IL (United States)); Thompson, A.C. (Materials and Components Tech. Div., Argonne National Lab., IL (United States)); Routbort, J.L. (Materials Science Div., Argonne National Lab., IL (United States))

1993-03-15

Solid-particle erosion was studied on AISI 4140 steel heat treated to have a Vickers hardness (Hv) of 288-650 kg mm[sup -2]. The experiments were conducted in vacuum with 143 [mu]m Al[sub 2]O[sub 3] abrasive impacting at 50-100 m s[sup -1] at an angle of 30 or 90 . Erosion rates were nearly independent of hardness for Hv[<=]365 kg mm[sup -2], but increased with hardness for Hv>365 kg mm[sup -2]. The improved erosion resistances of the softer alloys were attributed to increased ductilities. (orig.). Letter-to-the-editor

C1-2 vertebral anomalies in 22q11.2 microdeletion syndrome

Energy Technology Data Exchange (ETDEWEB)

Konen, Osnat; Armstrong, Derek; Padfield, Nancy; Blaser, Susan [Hospital for Sick Children, Diagnostic Imaging, Toronto (Canada); Clarke, Howard [Hospital for Sick Children, Plastic Surgery, Toronto (Canada); Weksberg, Rosanna [Hospital for Sick Children, Clinical and Metabolic Genetics, Toronto (Canada)

2008-07-15

Chromosome 22q11.2 microdeletion syndrome (22q11DS) is characterized by cleft palate, cardiac anomalies, characteristic facies, high prevalence of skeletal anomalies and learning disability. To evaluate the prevalence of craniovertebral junction anomalies in children with 22q11DS and compare these findings to those in nonsyndromic children with velopharyngeal insufficiency (VPI). Sequential CT scans performed for presurgical carotid assessment in 76 children (45 children positive for chromosome 22q11.2 deletion and 31 negative for the deletion) with VPI were retrospectively evaluated for assessment of C1-2 anomalies. C1-2 vertebral anomalies, specifically midline C1 defects, uptilted or upswept posterior elements of C2 and fusions of C2-3, were nearly universal in our cohort of 22q11DS patients with VPI. They were strikingly absent in the majority of non-22q11DS patients with VPI. C1-2 vertebral anomalies, particularly those listed above, are important radiographic markers for 22q11DS. (orig.)

C1-2 vertebral anomalies in 22q11.2 microdeletion syndrome

International Nuclear Information System (INIS)

Konen, Osnat; Armstrong, Derek; Padfield, Nancy; Blaser, Susan; Clarke, Howard; Weksberg, Rosanna

2008-01-01

Chromosome 22q11.2 microdeletion syndrome (22q11DS) is characterized by cleft palate, cardiac anomalies, characteristic facies, high prevalence of skeletal anomalies and learning disability. To evaluate the prevalence of craniovertebral junction anomalies in children with 22q11DS and compare these findings to those in nonsyndromic children with velopharyngeal insufficiency (VPI). Sequential CT scans performed for presurgical carotid assessment in 76 children (45 children positive for chromosome 22q11.2 deletion and 31 negative for the deletion) with VPI were retrospectively evaluated for assessment of C1-2 anomalies. C1-2 vertebral anomalies, specifically midline C1 defects, uptilted or upswept posterior elements of C2 and fusions of C2-3, were nearly universal in our cohort of 22q11DS patients with VPI. They were strikingly absent in the majority of non-22q11DS patients with VPI. C1-2 vertebral anomalies, particularly those listed above, are important radiographic markers for 22q11DS. (orig.)

Physical characterization of austenitic stainless steels AISI 304 and AISI 348 L*

International Nuclear Information System (INIS)

Teodoro, Celso Antonio; Silva, Jose Eduardo Rosa da

2009-01-01

The study of radiation damages in metals and metallic alloys used as structural materials in nuclear reactors has a strategic meaning to the nuclear technology because it treats of performance of these materials in conditions that simulate the conditions of work in power reactors. Then it becomes necessary to know the essential physical properties of these materials, properties that are sensitive to the microstructural changes that occurred during the irradiation. The purpose of this work is to characterize, initially, some pre-irradiation properties of the stainless steels AISI 304 and AISI 348 L * , such as mechanical (stress-strain and microhardness) and electrical (resistivity). The AISI 348 L * has been studied for use as fuel cladding material. Both materials will be tested after irradiation in the IEA-R1 core and their properties will be compared with those in the pre-irradiated condition. The morphology of the fractured zones after tensile tests was observed using SEM (scanning electron microscopy). (author)

Magnetic anisotropy of some R2CO17 compounds

International Nuclear Information System (INIS)

Khan, W.I.; Melville, D.

1978-01-01

The singular-point detection technique, in which the second derivative of the magnetization with respect to field is examined, has been used to determine the anisotropy field Bsub(A) = (2/Msub(s)) (K 1 + 2K 2 ) for Sm 2 Co 17 , Er 2 Co 17 , and Tm 2 Co 17 over the temperature range 77 - 300 K. Exrapolation of the initial part of the hard-direction magnetization curve for aligned powders enables K 1 and K 2 to be estimated. For Er 2 Co 17 and Tm 2 Co 17 the rare-earth (R) and cobalt sublattices are oppositely aligned, so that the onset of ordering of the R sublattice leads to a decrease in saturation magnetization as the temperature is lowered. This is in sharp contrast to the rapid increase in K 1 at low temperatures. By subtracting the corresponding Msub(s) values from that of Y 2 Co 17 the temperature dependence of the R sublattice can be determined. It is found that K 1 is directly proportional to the cube of this quantity, indicating the dominance of the rare-earth sublattice in determining the anisotropic properties of these compounds. For Sm 2 Co 17 the anisotropy constant varies very strongly with the reduced magnetization. (author)

Oxidation behaviour at 1123 K of AISI 304-Ni/Al-Al2O3/TiO2 multilayer system deposited by flame spray

Directory of Open Access Journals (Sweden)

Cervera, I.

2011-04-01

Full Text Available The oxidation behaviour of alumina/titania (97/3, 87/13 and 60/40 ceramic coatings using a Ni-Al coupling layer was studied in a thermobalance. Both layers were deposited on an AISI 304 stainless steel base metal by the flame spray technique. The coated steel was heated from room temperature to 1,123 K at 40 K min –1, oxidized in air for 50 h, and then cooled to room temperature at 40 K min–1. The mass gain was mainly attributed to the oxidation of Ni-Al coupling layer. Kinetic laws, DW·S –1 (mg.mm–2 vs. time (hours were close to a parabolic plot for each sample. Surface composition of ceramic top layer and the cross section of multilayer system were analysed using a wide range of experimental techniques including Scanning Electron Microscopy (SEM, equipped with a link energy dispersive X-Ray spectroscopy (EDX and X-Ray diffraction (XRD before and after the oxidation process. Coatings 97/3 and 87/13 presented a stable structure after flame spray deposition and they did not evolve with the oxidation process, while most of the 60/40 coating changed to a metastable structure after deposition and to a more stable structure after oxidation with high micro-cracks content. SEM and EDX microanalysis of the cross-sections showed that significant oxidation and a weak intergranular precipitation had been produced in the coupling layer and on the stainless steel base metal, respectively.El comportamiento a oxidación de recubrimientos cerámicos alúmina/titania (97/3, 87/13, 60/40 usando una capa de anclaje Ni-Al se ha estudiado mediante una termobalanza. Ambas capas se han depositado sobre un acero inoxidable AISI 304 utilizando la técnica de proyección llama (FS. El acero recubierto se ha calentado desde la temperatura ambiente hasta 1.123 K a 40 K min–1, se ha oxidado al aire durante 50 h, y luego se ha enfriado hasta la temperatura ambiente a 40 K min–1. La ganancia en masa se atribuye a la oxidación de la capa de enganche Ni-Al. La cin

Surface modifications induced by hydrogen in AISI 304 stainless steel

International Nuclear Information System (INIS)

Evangelista, G.E.; Miranda, P.E.V. de

1983-01-01

Hydrogen induced surface modifications of type AISI 304 SS were studied by charging the samples in a 1N a 1N H 2 SO 4 electrolyte at room temperature. Current densities were varied from 500 to 4000 A/m 2 and charging times from 2 to 50 hours. Charged specimens were analysed using optical and electron scanning microscopy. Vickers microhardness tests with small load was also performed. Metallographic etching metodologies were developed (in black and white and colored photographies) which permited identification of all phases present. It was shown that delayed cracks appear somewhat curved on austenite and perfectly strainght on martensite, following the intersections of a phase platlets. These are the regions where α' martensite is located. The habit plane of these cracks might belong to (100) sub(γ) or (221) sub(γ) plane families. A new phenomenon termed hydrogen induced softening was observed on type AISI 304 SS at elevated current densities and/or charging times. (Author) [pt

11 CFR 100.11 - State (2 U.S.C. 431(12)).

Science.gov (United States)

2010-01-01

... 11 Federal Elections 1 2010-01-01 2010-01-01 false State (2 U.S.C. 431(12)). 100.11 Section 100.11 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS (2 U.S.C. 431) General Definitions § 100.11 State (2 U.S.C. 431(12)). State means each State of the United States, the District of...

CYP2C19*17 increases clopidogrel-mediated platelet inhibition but does not alter the pharmacokinetics of the active metabolite of clopidogrel

DEFF Research Database (Denmark)

Pedersen, Rasmus Steen; Nielsen, Flemming; Stage, Tore Bjerregaard

2014-01-01

*1/*1, 11 CYP2C19*1/*17 and nine CYP2C19*17/*17). In Phase A, the pharmacokinetics of the derivatized active metabolite of clopidogrel (CAMD) and platelet function were determined after administration of a single oral dose of 600 mg clopidogrel (Plavix; Sanofi-Avensis, Horsholm, Denmark). In Phase B...

Replication the association of 2q32.2-q32.3 and 14q32.11 with hepatocellular carcinoma.

Science.gov (United States)

Chen, Wei; Wang, Mingquan; Zhang, Zhen; Tang, Huayang; Zuo, Xianbo; Meng, Xiangling; Xiong, Maoming; Zhou, Fusheng; Liang, Bo; Dai, Fen; Fang, Jun; Gao, Jinping; Zhu, Jun; Zhu, Yong; Wan, Hong; Wang, Miaofeng; Chan, Shixin; Sun, Liangdan

2015-04-25

Hepatocellular carcinoma (HCC) is a malignant tumor. The morbidity and mortality of HCC tend to ascend and become a serious threat to the population health. Genetic studies of HCC have identified several susceptibility loci of HCC. In this study, we aim to replicate the association of these loci in our samples from Chinese population and further investigate the genetic interaction. We selected 16 SNPs within 1p36.22, 2q32.2-q32.3, 3p21.33, 8p12, 14q32.11 and 21q21.3 and genotyped in 507 HCC patients and 3014 controls by using Sequenom MassARRAY system. Association analyses were performed by using PLINK 1.07. We observed that the STAT4 (2q32.2-q32.3) at rs7574865 (P=1.17×10(-3), OR=0.79) and EFCAB11 (14q32.11) at rs8013403 (P=1.54×10(-3), OR=0.80) were significantly associated with HCC in this study. In 3p21.33, genetic variant rs6795737 within GLB1 was also observed with suggestive evidence (P=9.98×10(-3), OR=0.84). In the interaction analysis, the pair of associated SNPs (rs7574865 within STAT4, rs8013403 within EFCAB11) generated evidence for interaction (P=4.10×10(-3)). In summary, our work first reported the association of 14q32.11 (EFCAB11) with HCC in Chinese Han population and revealed the genetic interaction between STAT4 (2q32.2-q32.3) and EFCAB11 (14q32.11) in HCC. Copyright © 2015 Elsevier B.V. All rights reserved.

11 CFR 110.17 - Price index increase.

Science.gov (United States)

2010-01-01

... 11 Federal Elections 1 2010-01-01 2010-01-01 false Price index increase. 110.17 Section 110.17... PROHIBITIONS § 110.17 Price index increase. (a) Price index increases for party committee expenditure... 11 CFR 109.32 and 110.8 shall be increased by the percent difference between the price index, as...

16,17-Seco- and 2,3:16,17-di-seco-pregnanes from Guarea guidonia

Energy Technology Data Exchange (ETDEWEB)

Garcez, Walmir Silvan; Garcez, Fernanda Rodrigues [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Dept. de Quimica]. E-mail: wgarcez@nin.ufms.br; Soares, Luzinatia Ramos [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Dept. de Quimica; Universidade Estadual de Mato Grosso do Sul, Campo Grande, MS (Brazil)

2008-07-01

Two new seco- and di-seco-pregnanes, 2{alpha},3{beta}-dihydroxy-16,17-seco-pregn-17-ene-16-oic acid methyl ester 2{beta},19-hemiketal (1) and 2,3:16,17-di-seco-pregn-17-ene-3-oic acid-16-oic acid methyl ester-19-hydroxy-2-carboxylic acid-2,19-lactone (2), have been obtained from the trunk bark of Guarea guidonia. Their structures have been established by a combination of 1D- and 2D-NMR spectroscopic techniques and MS data. The unique seco- and di-seco-pregnane carbocyclic skeletal types as found in compounds 1 and 2 are being reported in the Meliaceae for the first time as well as the occurrence of pregnanes in the genus Guarea. (author)

17 CFR 270.17f-2 - Custody of investments by registered management investment company.

Science.gov (United States)

2010-04-01

... registered management investment company. 270.17f-2 Section 270.17f-2 Commodity and Securities Exchanges....17f-2 Custody of investments by registered management investment company. (a) The securities and similar investments of a registered management investment company may be maintained in the custody of such...

Gadolinium heteropoly complex K 17[Gd(P 2W 17O 61) 2] as a potential MRI contrast agent

Science.gov (United States)

Sun, Guoying; Feng, Jianghua; Wu, Huifeng; Pei, Fengkui; Fang, Ke; Lei, Hao

2004-10-01

Gadolinium heteropoly complex K17[Gd(P2W17O61)2] has been evaluated by in vitro and in vivo experiments as a potential contrast agent for magnetic resonance imaging (MRI). The thermal analysis and conductivity study indicate that this complex has good thermal stability and wide pH stability range. The T1 relaxivity is 7.59 mM-1 s-1 in aqueous solution and 7.97 mM-1 s-1 in 0.725 mmol l-1 bovine serum albumin (BSA) solution at 25 °C and 9.39 T, respectively. MR imaging of three male Sprague-Dawley rats showed remarkable enhancement in rat liver after intravenous injection, which persisted longer than with Gd-DTPA. The signal intensity increased by 57.1±16.9% during the whole imaging period at 0.082 mmol kg-1dose. Our preliminary in vitro and in vivo studies indicate that K17[Gd(P2W17O61)2] is a potential liver-specific MRI contrast agent.

The study on the properties of AISI 4140 and AISI 1040 steel rods welded by friction welding

Directory of Open Access Journals (Sweden)

Thanee Toomprasen

2014-06-01

Full Text Available This paper is aimed to investigate the properties of joint between AISI 4140 and AISI 1040 welded by friction welding. The specimens were prepared in round shape of 13 mm diameter and 100 mm long. They were welded by friction welding method under the following conditions; friction pressure of 183 MPa, friction time of 12 sec, upset pressure of 428 MPa, upset time of 7 sec. and rotational speed of 1400 rpm. The strength and hardness were tested on the welded area. The result showed finer grains. in the welded area. This is the result of friction pressure and upset pressure in the welding process. In addition, the observation result indicated some changes of Ferrite and Pearlite in welded zone. This phase change resulted in the increment of hardness in AISI 4140 at the contact area and adjacent. In part of AISI 1040, the portion of Pearlite and Ferrite are not significantly changed, therefore the value of hardness is almost constant.

Wear behavior of niobium carbide coated AISI 52100 steel

International Nuclear Information System (INIS)

Fernandes, Frederico Augusto Pires; Casteletti, Luiz Carlos; Oliveira, Carlos Kleber Nascimento de; Lombardi Neto, Amadeu; Totten, George Edward

2010-01-01

Bearing steels must have high hardness, good wear resistance and dimensional stability. The aim of this work was to study the effect of NbC coating, produced using the thermo-reactive deposition (TRD) process, on the wear resistance of the AISI 52100 steel. Untreated AISI 52100 samples were ground up to 600 mesh emery paper. The bath was composed of 5wt.% ferroniobium (65 wt.% Nb), 3wt.% aluminum and (Na2B4O7) to 100%. Samples were treated at 1000 deg C for 4h and quenched in oil directly from the bath. The resulting layer was characterized by X-ray diffraction, scanning electron microscopy and a micro-abrasive wear testing. The thermo-reactive deposition process in molten borax produced a hard and homogeneous layer composed by NbC, which was confirmed by X-ray diffraction. The NbC coating produced a great increase in the wear resistance of the AISI 52100 steel, decreasing the wear rate by an order of magnitude in relation to the substrate. For coated and uncoated samples the worn volume and wear rate increases with the load. (author)

Study of carbonitriding thermochemical treatment by plasma screen in active with pressures main austenitic stainless steels AISI 409 and AISI 316L; Estudo do tratamento termoquimico de carbonitretacao por plasma em tela ativa com pressoes variaveis nos acos inoxidaveis austenitico AISI 316L e ferririco AISI 409

Energy Technology Data Exchange (ETDEWEB)

Melo, M.S.; Oliveira, A.M.; Leal, V.S.; Sousa, R.R.M. de; Alves Junior, C. [Centro Federal de Educacao Tecnologica do Maranhao (CEFET/MA), Sao Luis, MA (Brazil); Centro Federal de Educacao Tecnologica do Piaui (CEFET/PI), Teresina, PI (Brazil); Universidade Federal do Rio Grande do Norte (DF/UFRN), Natal, RN (Brazil). Dept. de Fisica. Labplasma

2010-07-01

The technique called Active Screen Plasma Nitriding (ASPN) is being used as an alternative once it offers several advantages with respect to conventional DC plasma. In this method, the plasma does not form directly in the sample's surface but on a screen, in such a way that undesired effects such as the edge effect is minimized. Stainless steels present not very satisfactory wearing characteristics. However, plasma carbonitriding has been used as to improve its resistance to wearing due to the formation of a fine surface layer with good properties. In this work, samples of stainless steel AISI 316L and AISI 409 were treated at pressures of 2.5 and 5 mbar. After the treatments they were characterized by microhardness, microscopy and Xray diffraction. Microscopy and hardness analysis showed satisfactory layers and toughness in those steels. (author)

Wear and friction behaviour of duplex-treated AISI 4140 steel

Energy Technology Data Exchange (ETDEWEB)

Podgornik, B.; Vizintin, J. [Ljubljana Univ. (Slovenia). Centre of Tribology and Technical Diagnostics; Waenstrand, O.; Larsson, M.; Hogmark, S. [The Aangstroem Laboratory, Uppsala University, Box 534, SE-75121, Uppsala (Sweden)

1999-11-01

In this study samples of AISI 4140 steel were pretreated by plasma nitriding and coated with two different physical vapour deposited coatings (TiN and TiAlN). A hardened AISI 4140 sample and a coated sample were also included in the investigation. To examine the influence of the nitrided zone on the performance of the coating-substrate composite, two different nitriding conditions - a conventional 25% N{sub 2} and an N{sub 2}-poor gas mixture - were used. The specimens were investigated with respect to their microhardness, surface roughness, scratch adhesion and dry sliding wear resistance. Wear tests in which the duplex-treated pins were mated to hardened ball bearing steel discs were performed in a pin-on-disc machine under dry sliding conditions. Metallography, scanning electron microscopy and profilometry were used to analyse the worn surfaces in order to determine the dominant friction and wear characteristics of the samples investigated. The results show improved wear properties of the plasma-nitrided hard-coated specimens compared with uncoated and pre-hardened ones. Although previous investigations showed a negative effect of the compound layer, it was found that a precisely controlled plasma nitriding process can lead to a dense, uniform and highly adherent compound layer with a positive effect on the wear properties of pre-nitrided and hard-coated AISI 4140 steel. (orig.)

28 CFR 11.2 - Pilot program.

Science.gov (United States)

2010-07-01

... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Pilot program. 11.2 Section 11.2 Judicial... Pilot program. The Assistant Attorney General for Administration, in consultation with the Executive Office for United States Attorneys, shall designate the districts that will participate in the pilot...

17 CFR 240.17h-2T - Risk assessment reporting requirements for brokers and dealers.

Science.gov (United States)

2010-04-01

... requirements for brokers and dealers. 240.17h-2T Section 240.17h-2T Commodity and Securities Exchanges... Organizations § 240.17h-2T Risk assessment reporting requirements for brokers and dealers. (a) Reporting requirements of risk assessment information required to be maintained by section 240.17h-1T. (1) Every broker...

X-ray and Hydrogen-bonding Properties of 1-((1H-benzotriazol-1-ylmethylnaphthalen-2-ol

Directory of Open Access Journals (Sweden)

Jaime Ríos-Motta

2009-03-01

Full Text Available The solid state structure of 1-((1H-benzotriazol-1-ylmethylnaphthalen-2-ol, C17H13N3O, shows that this Mannich base crystallizes forming intermolecular N···HO hydrogen bonds, rather than intramolecular ones. Factors contributing to this choice of hydrogen-bonding mode are discussed. The compound crystallizes in the monoclinic system, P21/c space group, with lattice constants: a = 11.7934(9 Å, b = 14.3002(14 Å, c = 8.4444(8 Å, β = 106.243(5 deg, V = 1367.3(2 Å3, Z = 4, F(000 = 576, R1 = 6.96%, wR2 = 11.4%.

Examining the Overlap between Autism Spectrum Disorder and 22q11.2 Deletion Syndrome.

Science.gov (United States)

Ousley, Opal; Evans, A Nichole; Fernandez-Carriba, Samuel; Smearman, Erica L; Rockers, Kimberly; Morrier, Michael J; Evans, David W; Coleman, Karlene; Cubells, Joseph

2017-05-18

22q11.2 deletion syndrome (22q11.2DS) is a genomic disorder reported to associate with autism spectrum disorders (ASDs) in 15-50% of cases; however, others suggest that individuals with 22q11.2DS present psychiatric or behavioral features associated with ASDs, but do not meet full criteria for ASD diagnoses. Such wide variability in findings may arise in part due to methodological differences across studies. Our study sought to determine whether individuals with 22q11.2DS meet strict ASD diagnostic criteria using research-based guidelines from the Collaborative Programs of Excellence in Autism (CPEA), which required a gathering of information from three sources: the Autism Diagnostic Interview-Revised (ADI-R), the Autism Diagnostic Observational Schedule (ADOS), and a clinician's best-estimate diagnosis. Our study examined a cohort of children, adolescents, and young adults ( n = 56) with 22q11.2DS, who were ascertained irrespective of parents' behavioral or developmental concerns, and found that 17.9% ( n = 10) of the participants met CPEA criteria for an ASD diagnosis, and that a majority showed some level of social-communication impairment or the presence of repetitive behaviors. We conclude that strictly defined ASDs occur in a substantial proportion of individuals with 22q11.2DS, and recommend that all individuals with 22q11.2DS be screened for ASDs during early childhood.

Experimental study of the chip morphology in turning hardened AISI D2 steel

Energy Technology Data Exchange (ETDEWEB)

Mhamdi, Mohamed Baccar; Bayraktar, Emin [Supmeca, Paris (France); Salem, Sahbi Ben; Boujelbene, Mohamed [National Engineering School of Tunis, Tunis (Turkey)

2013-11-15

The study of local mechanisms of material removal is essential in all problems of shaping by machining. Indeed, the mastery of surfaces generated by cutting requires an understanding of cutting mechanisms. The turning of steels with high mechanical properties using the cutting tool, often called 'hard turning,' is a new technique for the mechanical industry, and hence the need to understand the cutting mechanisms. The steel type EN X160CrMoV12 treated to 62 HRC (cold work tool steel: AISI D2 with a martensite matrix and distribution of primary and secondary carbides) is the subject of this study. Hard turning tests were carried out for this steel at different cutting conditions, with the aim to understand the mechanism of chip formation in order to be able to obtain the optimal cutting conditions. The chips obtained were examined under a microscope. The observation showed that the chip formation is influenced by cutting conditions. The chips contained a white layer, and this layer was examined under scanning electronic microscope (SEM) to study its variation depending on cutting parameters. The study shown, that cutting forces decrease with the increase of cutting speed. However, ANOVA method was used to establish the effect of the cutting conditions on experimental obtained results. Analysis of plastic deformation of the chip and the shear angle was made according to cutting conditions. Finally, a microhardness test was carried out to relate the mechanical properties and the microstructures of white layers.

Diffused zircaloy 2/stainless steel junctions; Jonctions diffusees zircaloy 2 - acier inoxydable

Energy Technology Data Exchange (ETDEWEB)

Jacques, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-07-01

The diffusion permits to realize joints between two different materials, in fact of the formation of a liquid phase at the contact face. The study of the tensile properties allowed the determination of the ideal conditions for the diffusion treatment which are, within 2 and 3 minutes for a temperature within 1020 C and 1030 C. The characteristics of the so obtained joints were, studied: mechanical properties, tightness, resistance to thermal cycling. Analysis of the thermal stress, owing to the differential dilatation of the two materials mode the object of a particular study. The investigation on the diffusion zone, includes specially, an analysis of the constituents distribution formed during the diffusion treatment. (author) [French] La diffusion permet de realiser des joints entre deux materiaux differents, du fait de la formation d'une phase liquide a l'interface de contact. L'etude de la resistance a la traction a permis de determiner les conditions optimum du traitement de diffusion: une duree de 2 a 3 minutes pour une temperature comprise entre 1020 C et 1030 C. Les caracteristiques des jonctions ainsi obtenues ont ete etudiees: proprietes mecaniques, etancheite, resistance au cyclage thermique. L'analyse des contraintes thermiques dues a la difference de dilatation des deux materiaux, a fait l'objet d'une etude particuliere. L'etude metallurgique de la zone diffusee comporte en particulier une analyse de la repartition des constituants formes lors du traitement de diffusion. (auteur)

Evaluation of Microstructure and Toughness of AISI D2 Steel by Bright Hardening in Comparison with Oil Quenching

Science.gov (United States)

Torkamani, H.; Raygan, Sh.; Rassizadehghani, J.

2011-12-01

AISI D2 is used widely in the manufacture of blanking and cold-forming dies, on account of its excellent hardness and wear behavior. Increasing toughness at a fixed high level of hardness is growing requirement for this kind of tool steel. Improving microstructure characteristics, especially refinement of coarse carbides, is an appropriate way to meet such requirement. In this study, morphology and size of carbides in martensite matrix were compared between two kinds of samples, which were bright hardened (quenching in hot alkaline salt bath consisting of 60% KOH and 40% NaOH) at 230 °C and quenched in oil bath at 60 °C. Results showed that morphology and distribution of carbides in samples performed by bright hardening were finer and almost spherical compared to that of oil quenched. This microstructure resulted in an improvement in toughness and tensile properties of alloy.

Liquid-liquid extraction to lithium isotope separation based on room-temperature ionic liquids containing 2,2'-binaphthyldiyl-17-crown-5

International Nuclear Information System (INIS)

Sun Xiaoli; Zhou Wen; Gu Lin; Qiu Dan; Ren Donghong; Gu Zhiguo; Li Zaijun

2015-01-01

A novel liquid-liquid extraction system was investigated for the selective separation of lithium isotopes using ionic liquids (ILs = C 8 mim + PF 6 - , C 8 mim + BF 4 - , and C 8 mim + NTf 2 - ) as extraction solvent and 2,2'-binaphthyldiyl-17-crown-5 (BN-17-5) as extractant. The effects of the concentration of lithium salt, counter anion of lithium salt, initial pH of aqueous phase, extraction temperature, and time on the lithium isotopes separation were discussed. Under optimized conditions, the maximum single-stage separation factor α of 6 Li/ 7 Li obtained in the present study was 1.046 ± 0.002, indicating the lighter isotope 6 Li was enriched in IL phase while the heavier isotope 7 Li was concentrated in the solution phase. The formation of 1:1 complex Li(BN-17-5) + in the IL phase was determined on the basis of slope analysis method. The large value of the free energy change (-ΔG° = 92.89 J mol -1 ) indicated the high separation capability of the Li isotopes by BN-17-5/IL system. Lithium in Li(BN-17-5) + complex was stripped by 1 mol L -1 HCl solution. The extraction system offers high efficiency, simplicity, and green application prospect to lithium isotope separation. (author)

Study of residual stresses generated in machining of AISI 4340 steel

International Nuclear Information System (INIS)

Reis, W.P. dos; Fonseca, M.P. Cindra; Serrao, L.F.; Chuvas, T.C.; Oliveira, L.C.

2010-01-01

Among the mechanical construction steels, AISI 4340 has good harden ability, while combining high strength with toughness and good fatigue strength, making it excellent for application in the metalworking industry, where it can work at different levels and types of requests. Residual stresses are generated in almost all processes of mechanical manufacturing. In this study, the residual stresses generated in different machining processes and heat treatment hardening of AISI 4340 were analyzed by X-ray diffraction, by the sen 2 ψ method, using Crκβ radiation and compared. All samples, except for turned and cut by EDM, presented compressive residual stresses in the surface with various magnitudes. (author)

Development of Nb{sub 2}O{sub 5}|Cu composite as AISI 1020 steel thermal spray coating for protection against corrosion by soil in buried structures; Desenvolvimento e uso do composito de Nb{sub 2}O{sub 5}|Cu como revestimento aplicado por aspersao termica sobre o aco AISI 1020 para protecao contra a corrosao pelo solo em estruturas enterradas

Energy Technology Data Exchange (ETDEWEB)

Regis Junior, Oscar [Universidade Tecnologica Federal do Parana, Ponta Grossa, PR (Brazil). Dept. de Mecanica; Silva, Jose Maurilio da; Portella, Kleber Franke [Instituto de Tecnologia para o Desenvolvimento, Curitiba, PR (Brazil). Dept. de Pesquisa em Engenharia Civil; Paredes, Ramon Sigifredo Cortes, E-mail: regis@utfpr.edu.br [Universidade Federal do Parana, Curitiba, PR (Brazil). Dept. de Mecanica

2012-07-01

An Nb{sub 2}O|Cu corrosion-resistant coating was developed and applied onto AISI 1020 steel substrate by Powder Flame Spray. A galvanostatic electrochemical technique was employed, with and without ohmic drop, in four different soils (two corrosively aggressive and two less aggressive). Behavior of coatings in different soils was compared using a cathodic hydrogen reduction reaction (equilibrium potential, overvoltage and exchange current density) focusing on the effect of ohmic drop. Results allow recommendation of Nb{sub 2}O{sub 5}|Cu composite for use in buried structure protection. (author)

Double cascade erbium fiber laser at 1.7 µm, 2.7 µm, and 1.6 µm

NARCIS (Netherlands)

Schneider, J.; Frerichs, Ch.; Carbonnier, C.; Unrau, U.B.; Pollnau, Markus; Lüthy, W.; Weber, H.P.

The output power of the erbium laser at 2.7 um (4I11/2 -> 4I13/2) is enhanced due to simultaneous laser action at 1.7 um (4S3/2 -> 4I9/2) and 1.6 um (4I13/2 -> 4I15/2) in an Er3+-doped fluorozirconate fiber. The laser cascade overwhelms the saturation effect for the transition at 2.7 um by

Effect of introduction atoms on effective exchange field in ferrimagnetic rare earth compounds and 3d-transition metal compounds such as R2Fe17 and RFe11Ti

International Nuclear Information System (INIS)

Nikitin, S.A.; Tereshina, I.S

2003-01-01

The magnetic properties of the ferrimagnetic compounds R 2 Fe 17 and RFe 11 Ti, as well as their hydrides and nitrides are studied. The change in the exchange fields, effecting the rare earth (RE) ions both from the side of the Fe sublattice and from the side of other RE ions in the process of hydrogenation and nitration is determined and Curie temperature dependence of the source compounds, their hydrides and nitrides on the de Genes factor is identified. It is established that in the course of the light atoms (H and N) introduction into the crystalline lattice of the R 2 Fe 17 and RFe 11 Ti compounds there takes place significant increase in the Curie temperature, in the Fe-Fe exchange interactions and decrease in the R-R interactions. This may be interpreted as the result of the oc curing changes in the electron structures of such compounds and indirect exchange interactions [ru

Radiation-induced evolution of austenite matrix in silicon-modified AISI 316 alloys

International Nuclear Information System (INIS)

Garner, F.A.; Brager, H.R.

1980-01-01

The microstructures of a series of silicon-modified AISI 316 alloys irradiated to fast neutron fluences of about 2-3 and 10 x 10 22 n/cm 2 (E > 0.1 MeV at temperatures ranging from 400 0 C to 600 0 C have been examined. The irradiation of AISI 316 leads to an extensive repartition of several elements, particularly nickel and silicon, between the matrix and various precipitate phases. The segregation of nickel at void and grain boundary surfaces at the expense of other faster-diffusing elements is a clear indication that one of the mechanisms driving the microchemical evolution is the Inverse Kirkendall effect. There is evidence that at one sink this mechanism is in competition with the solute drag process associated with interstitial gradients

Predominance of genotype 1.1 and emergence of genotype 2.2 classical swine fever viruses in north-eastern region of India.

Science.gov (United States)

Roychoudhury, P; Sarma, D K; Rajkhowa, S; Munir, M; Kuchipudi, S V

2014-08-01

Classical swine fever (CSF) is a highly contagious and the most important disease of pigs worldwide.CSF is enzootic in pig herds in India and continues to cause huge economic losses to pig farmers. Nearly 40% of the total pig population of India is present in the north-eastern (NE) states where pig husbandry plays an important role in the socio-economic development. Pigs reared in the backyards are the only source of livelihood for a majority of poor tribal population in the region. Hardly any CSF vaccination is currently being undertaken in the unorganized pig farming in the NE region due to economic reasons and vaccine unavailability. A thorough understanding of the current epidemiological status of CSF is essential for the effective control of the disease in the NE region. Hence, we carried out molecular characterization of CSFV isolates from field outbreaks during 2011-2012 in the entire north-eastern region of India to establish the genetic groups of prevalent CSF viruses in the region. A total of 17 CSFV isolates obtained from different parts of the NE region were characterized by comparing the sequences of three partial genomic regions of the virus, that is 150 nt of 5' UTR, 190 nt of E2 and 409 nt of NS5B. Of the 17 CSFV isolates, 15 isolates belonged to 1.1 (88.2%) and two isolates (11.8%) belonged to 2.2 subgenogroup. The genogroup 2.2 CSFV were associated with outbreaks in Arunachal Pradesh that shares international borders with Bhutan, Myanmar and China. Genogroup 2.2 CSFV isolated in the present study shared high level of sequence similarity with 2.2 viruses form China, raising the possibility of virus incursion from this region. In summary, we found a continued predominance of 1.1 subgroup and an emergence of 2.2 subgroup CSFV in NE region of India. © 2014 Blackwell Verlag GmbH.

Simultaneous enhancement of strength and ductility in cryogenically treated AISI D2 tool steel

Energy Technology Data Exchange (ETDEWEB)

Ghasemi-Nanesa, Hadi; Jahazi, Mohammad, E-mail: mohammad.jahazi@etsmtl.ca

2014-03-01

In this research, the effect of cryogenic treatment on microstructural evolution and mechanical properties enhancement of AISI D2 tool steel was investigated. Cryogenic treatment down to liquid nitrogen temperature (77 K) was added to the conventional heat treatment between hardening and tempering steps. Electron microscopy investigation showed higher volume fraction of fine carbides with average diameter below 1 μm indicating effective retardation in carbide coarsening process as a results of cryogenic treatment. A modification in types of carbides was also observed after cryogenic treatment. X-ray diffraction diagrams revealed transformation of retained austenite to martensite at cryogenic temperature. Weakening or removal of carbides peak in the X-ray diagram was considered as evidence of carbides different behavior at cryogenic temperature. Mechanical testing results indicated higher ultimate tensile strength, better ductility, and higher elastic modulus after cryogenic treatment. Analysis of stress–strain diagrams revealed different strain hardening behavior for cryogenically treated alloy when compared to the conventionally heat treated one. Fractography results confirmed strain hardening behavior and showed cleavage fracture for conventionally treated alloy but mixed cleavage–ductile fracture mode for cryogenically treated alloy. The improved mechanical properties after cryogenic treatment are interpreted in terms of the influence of higher volume fraction and uniform distribution of fine carbides in reducing the average active dislocations length and enhancement of the flow stress at any given plastic strain.

Simultaneous enhancement of strength and ductility in cryogenically treated AISI D2 tool steel

International Nuclear Information System (INIS)

Ghasemi-Nanesa, Hadi; Jahazi, Mohammad

2014-01-01

In this research, the effect of cryogenic treatment on microstructural evolution and mechanical properties enhancement of AISI D2 tool steel was investigated. Cryogenic treatment down to liquid nitrogen temperature (77 K) was added to the conventional heat treatment between hardening and tempering steps. Electron microscopy investigation showed higher volume fraction of fine carbides with average diameter below 1 μm indicating effective retardation in carbide coarsening process as a results of cryogenic treatment. A modification in types of carbides was also observed after cryogenic treatment. X-ray diffraction diagrams revealed transformation of retained austenite to martensite at cryogenic temperature. Weakening or removal of carbides peak in the X-ray diagram was considered as evidence of carbides different behavior at cryogenic temperature. Mechanical testing results indicated higher ultimate tensile strength, better ductility, and higher elastic modulus after cryogenic treatment. Analysis of stress–strain diagrams revealed different strain hardening behavior for cryogenically treated alloy when compared to the conventionally heat treated one. Fractography results confirmed strain hardening behavior and showed cleavage fracture for conventionally treated alloy but mixed cleavage–ductile fracture mode for cryogenically treated alloy. The improved mechanical properties after cryogenic treatment are interpreted in terms of the influence of higher volume fraction and uniform distribution of fine carbides in reducing the average active dislocations length and enhancement of the flow stress at any given plastic strain

Machining tools in AISI M2 high-speed steel obtained by spray forming process

International Nuclear Information System (INIS)

Jesus, Edilson Rosa Barbosa de.

2004-01-01

The aim of the present work was the obtention of AISI M2 high-speed steel by spray forming technique and the material evaluation when used as machining tool. The obtained material was hot rolled at 50% and 72% reduction ratios, and from which it was manufactured inserts for machining tests. The performance of inserts made of the spray formed material was compared to inserts obtained from conventional and powder metallurgy (MP) processed materials. The spray formed material was chemical, physical, mechanical and microstructural characterised. For further characterisation, the materials were submitted to machining tests for performance evaluation under real work condition. The results of material characterisation highlight the potential of the spray forming technique, in the obtention of materials with good characteristics and properties. Under the current processing, hot rolling and heat treatments condition, the analysis of the results of the machining tests revealed a very similar behaviour among the tested materials. Proceeding a criterious analysis of the machining results tests, it was verified that the performance presented by the powder metallurgy material (MP) was slight superior, followed by conventional obtained material (MConv), which presented a insignificant advantage over the spray formed and hot rolled (72% reduction ratio) material. The worst result was encountered for the spray forming and hot rolled (50% reduction ratio) material that presented the highest wear values. (author)

Study of carbonitriding thermochemical treatment by plasma screen in active with pressures main austenitic stainless steels AISI 409 and AISI 316L

International Nuclear Information System (INIS)

Melo, M.S.; Oliveira, A.M.; Leal, V.S.; Sousa, R.R.M. de; Alves Junior, C.; Centro Federal de Educacao Tecnologica do Piaui; Universidade Federal do Rio Grande do Norte

2010-01-01

The technique called Active Screen Plasma Nitriding (ASPN) is being used as an alternative once it offers several advantages with respect to conventional DC plasma. In this method, the plasma does not form directly in the sample's surface but on a screen, in such a way that undesired effects such as the edge effect is minimized. Stainless steels present not very satisfactory wearing characteristics. However, plasma carbonitriding has been used as to improve its resistance to wearing due to the formation of a fine surface layer with good properties. In this work, samples of stainless steel AISI 316L and AISI 409 were treated at pressures of 2.5 and 5 mbar. After the treatments they were characterized by microhardness, microscopy and Xray diffraction. Microscopy and hardness analysis showed satisfactory layers and toughness in those steels. (author)

Comparison of the corrosion resistance of DIN W. Nr. 1.4970 (15%Cr-15%Ni-1.2%Mo-Ti and ASTM F-138 (17%Cr-13%Ni-2.5%Mo austenitic stainless steels for biomedical applications

Directory of Open Access Journals (Sweden)

Maysa Terada

2006-09-01

Full Text Available The resistance to localised corrosion of the full austenitic 15%Cr-15%Ni-1.2%Mo titanium stabilized stainless steel (DIN W. Nr. 1.4970 was investigated by electrochemical methods including electrochemical impedance spectroscopy (EIS, potentiodynamic polarization and potentiostatic polarization measurements in a phosphate-buffered solution (PBS. The low carbon and non-stabilized austenitic stainless steel, AISI 316L (ASTM F-138, widely used for surgical implants, was also tested for comparison. The tests were conducted at room temperature after a stable potential had been reached. After the electrochemical measurements, the surfaces of the specimens were observed using SEM to evaluate the presence of pits. Potentiodynamic polarization results showed that both steels are prone to localized corrosion. Larger pits were found on the surface of AISI 316L specimens after the electrochemical tests. EIS response has indicated the duplex structure of the passive oxides. The results showed that the electrochemical behaviour of the DIN W. Nr. 1.4970 is better than of AISI 316L steel. Therefore, their application as an implant material may be considered.

(3-Benzoyl-1,7,7-trimethylbicyclo[2.2.1]heptan-2-olato-κ2O,Obis[2-(2-pyridylphenyl-κ2C1,N]iridium(III

Directory of Open Access Journals (Sweden)

Kaijun Luo

2011-11-01

Full Text Available The title compound, [Ir(C11H8N2(C17H19O2], has an octahedral coordination geometry around the IrIII atom, retaining the cis-C,C,trans–N,N chelate disposition of the two 2-phenylpyridine ligands. The chelate rings are nearly mutually perpendicular [the interplanar angles range from 85.48 (17 to 89.17 (19°]. The two 2-(2-pyridylphenyl ligands are approximately planar, with the plane of the phenyl ring being inclined to that of the pyridine ring by 2.3 (3 and 5.1 (3° in the two ligands. The interplanar angle between the phenyl ring in 3-benzoyl-camphor and the IrO2C3 chelate ring is 35.5 (2°.

Effects of IGFBP-2 on proliferation and differentiation in neural stem cell line C17.2

Directory of Open Access Journals (Sweden)

Deng Y

2017-07-01

Full Text Available Yujia Deng,1 Lei Wang,1,2 Lite Ge,1,3 Da Duan,1 Yi Zhuo,1 Ting Yuan,1 Weiping Yan,1 Peiqi Huang,1 Xiaohua Teng,1 Ming Lu1,3 1Department of Neurosurgery, The Second Affiliated Hospital of Hunan Normal University (163 Hospital of the People’s Liberation Army, Changsha, 2Department of Neurosurgery, Affiliated Haikou Hospital, Xiangya School of Central South University, Haikou, 3Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, People’s Republic of China Objective: Insulin-like growth factor binding protein-2 (IGFBP-2, a member of a highly conserved family of six insulin-like growth factor binding proteins (IGFBPs, can regulate several cellular processes through IGF-dependent or IGF-independent pathway. Recent studies have provided solid evidence for the importance to delineate that olfactory ensheathing cells (OEC-conditioned medium (OCM can not only facilitate the differentiation of neural stem cell line (C17.2 into neurons, but also promote the survival and proliferation. We have previously reported that IGFBP-2 was detected in OCM. This study is designed to investigate the roles of IGFBP-2 for the regulation of C17.2 differentiation and proliferation.Methods and results: IGFBP-2 was identified and upregulated in OCM to compare with astrocytes-conditioned medium by shotgun proteomics and semiquantitative proteomic analysis. In order to investigate whether exogenous IGFBP-2 could stimulate proliferation in C17.2 cells and differentiate it into glia or neuron, we used various concentrations of IGFBP-2 to induce C17.2 cells which were cultured in DMEM/F12. The results showed that exogenous IGFBP-2 can promote proliferation in C17.2 cells, but had little effect on differentiation. Interestingly, we also found that IGFBP-2 could induce C17.2 cells to differentiate into astrocytes, while inhibiting their differentiation into neurons in a dose

Examining the Overlap between Autism Spectrum Disorder and 22q11.2 Deletion Syndrome

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Opal Ousley

2017-05-01

Full Text Available 22q11.2 deletion syndrome (22q11.2DS is a genomic disorder reported to associate with autism spectrum disorders (ASDs in 15–50% of cases; however, others suggest that individuals with 22q11.2DS present psychiatric or behavioral features associated with ASDs, but do not meet full criteria for ASD diagnoses. Such wide variability in findings may arise in part due to methodological differences across studies. Our study sought to determine whether individuals with 22q11.2DS meet strict ASD diagnostic criteria using research-based guidelines from the Collaborative Programs of Excellence in Autism (CPEA, which required a gathering of information from three sources: the Autism Diagnostic Interview-Revised (ADI-R, the Autism Diagnostic Observational Schedule (ADOS, and a clinician’s best-estimate diagnosis. Our study examined a cohort of children, adolescents, and young adults (n = 56 with 22q11.2DS, who were ascertained irrespective of parents’ behavioral or developmental concerns, and found that 17.9% (n = 10 of the participants met CPEA criteria for an ASD diagnosis, and that a majority showed some level of social-communication impairment or the presence of repetitive behaviors. We conclude that strictly defined ASDs occur in a substantial proportion of individuals with 22q11.2DS, and recommend that all individuals with 22q11.2DS be screened for ASDs during early childhood.

Catalytic conversion of 11CO2 and 11CO into synthesis precursors for 11C labelling

International Nuclear Information System (INIS)

Patt, J.T.

1994-03-01

The positron emitter carbon-11 (T 1/2 =20.3 min) is an ideal radio nuclide for tracers in positron emission tomography (PET). In this study catalytic methods for the synthesis of [ 11 C]alcohols have been investigated. The formation of [ 11 C]methanol has been studied on Pd/Al 2 O 3 and Cu/ZnO/Al 2 O 3 catalysts with respect to CO and CO 2 carrier addition to the synthesis gas. Carbon monoxide was identified as the precursor of methanol formation on the Pd/Al 2 O 3 -catalyst. In contrast on the Cu/ZnO/Al 2 O 3 -catalyst methanol was formed on a reaction pathway via an adsorbed CO 2 -species. A n.c.a.-[ 11 C]methanol synthesis basing on the Cu/ZnO/Al 2 O 3 -catalyst has been developed by substitution of the oxygen containing components CO and CO 2 in the synthesis gas by N 2 O. The radiochemical yield, the low selectivity of [ 11 C]methanol production and the rather slow kinetics of this process were arguments against the practical use of this process in the synthesis of 11 C-labelling agents. (orig.)

Identity by descent fine mapping of familial adult myoclonus epilepsy (FAME) to 2p11.2-2q11.2.

Science.gov (United States)

Henden, Lyndal; Freytag, Saskia; Afawi, Zaid; Baldassari, Sara; Berkovic, Samuel F; Bisulli, Francesca; Canafoglia, Laura; Casari, Giorgio; Crompton, Douglas Ewan; Depienne, Christel; Gecz, Jozef; Guerrini, Renzo; Helbig, Ingo; Hirsch, Edouard; Keren, Boris; Klein, Karl Martin; Labauge, Pierre; LeGuern, Eric; Licchetta, Laura; Mei, Davide; Nava, Caroline; Pippucci, Tommaso; Rudolf, Gabrielle; Scheffer, Ingrid Eileen; Striano, Pasquale; Tinuper, Paolo; Zara, Federico; Corbett, Mark; Bahlo, Melanie

2016-10-01

Familial adult myoclonus epilepsy (FAME) is a rare autosomal dominant disorder characterized by adult onset, involuntary muscle jerks, cortical myoclonus and occasional seizures. FAME is genetically heterogeneous with more than 70 families reported worldwide and five potential disease loci. The efforts to identify potential causal variants have been unsuccessful in all but three families. To date, linkage analysis has been the main approach to find and narrow FAME critical regions. We propose an alternative method, pedigree free identity-by-descent (IBD) mapping, that infers regions of the genome between individuals that have been inherited from a common ancestor. IBD mapping provides an alternative to linkage analysis in the presence of allelic and locus heterogeneity by detecting clusters of individuals who share a common allele. Succeeding IBD mapping, gene prioritization based on gene co-expression analysis can be used to identify the most promising candidate genes. We performed an IBD analysis using high-density single nucleotide polymorphism (SNP) array data followed by gene prioritization on a FAME cohort of ten European families and one Australian/New Zealander family; eight of which had known disease loci. By identifying IBD regions common to multiple families, we were able to narrow the FAME2 locus to a 9.78 megabase interval within 2p11.2-q11.2. We provide additional evidence of a founder effect in four Italian families and allelic heterogeneity with at least four distinct founders responsible for FAME at the FAME2 locus. In addition, we suggest candidate disease genes using gene prioritization based on gene co-expression analysis.

Marine Shaft Steels (AISI 4140 and AISI 5120 Predicted Fracture Toughness by FE Simulation

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Goran VUKELIC

2017-02-01

Full Text Available Optimal selection of material can be considered as one of the most critical steps in engineering design process. That is especially emphasized when dealing with constructions that operate in marine environment; high stresses and harsh operating conditions assert the importance of proper material characterization before its selection. This paper presents comparison of two types of steel usually used in marine shaft manufacturing, chromium-molybdenum steel AISI 4140 and chromium low-alloy steel AISI 5120. Comparison was made using numerically determined J-integral, an important fracture mechanics parameter. J-integral values are determined numerically using finite element (FE stress analysis results of compact tensile (CT and single-edge notched bend (SENB type specimens usually used in standardized J-integral experimental procedures. Obtained J values are plotted versus specimen crack growth values (Δa for different specimen geometries (a/W. Higher resulting values of J-integral for AISI 5120 than AISI 4140 can be noticed. Also, higher a/W ratios correspond to lower J-integral values of materials and vice versa. In addition to that, J-integral values obtained by using FE model of CT specimen give somewhat conservative results when compared with ones obtained by FE model of SENB specimen. Although this procedure differs from experimental analysis, results can be used a suitable fracture parameter value in fracture toughness assessment.DOI: http://dx.doi.org/10.5755/j01.ms.23.1.13823

Low temperature plasma carburizing of AISI 316L austenitic stainless steel and AISI F51 duplex stainless steel Cementação sob plasma à baixa temperatura do aço inoxidável austenítico AISI 316L e do aço inoxidável duplex AISI F51

OpenAIRE

Carlos Eduardo Pinedo; André Paulo Tschiptschin

2013-01-01

In this work an austenitic AISI 316L and a duplex AISI F51 (EN 1.4462) stainless steel were DC-Plasma carburized at 480ºC, using CH4 as carbon carrier gas. For the austenitic AISI 316L stainless steel, low temperature plasma carburizing induced a strong carbon supersaturation in the austenitic lattice and the formation of carbon expanded austenite (γC) without any precipitation of carbides. The hardness of the carburized AISI 316L steel reached a maximum of 1000 HV due to ∼13 at% c...

15,17-Di-2-propenylcalix[4]arene-25,26,27,28-tetrol: self-complexation and C-H...O interactions

NARCIS (Netherlands)

Harkema, Sybolt; van Loon, Jan-Dirk; van Loon, Jan-Dirk; Verboom, Willem; Reinhoudt, David

1998-01-01

The crystal structure of 15,17-di-2-propenylcalix[4]arene-25,26,27,28-tetrol [systematic name: 15,17-di-2-propenylpentacyclo[19.3.1.13,7.19,13.115,19]octacosa-1(25), 3,5,7(26),9,11,13 (27),15,17,19 (28),21,23-dodecaene-25,26,27,28-tetrol], C34H32O4, was determined. The calix[4]arene molecule shows a

Pitting Corrosion Susceptibility of AISI 301 Stainless Steel in ...

African Journals Online (AJOL)

The susceptibility of austenitic (AISI 301) stainless steel to pitting corrosion was evaluated in sodium chloride (NaCl) solutions - 0.1M, 0.2M, 0.3M, 0.5M and 0.7M and 1.0M. Tensile tests and microscopic examinations were performed on samples prepared from the steel after exposure in the various environments.

Comparative evaluation of laser-assisted micro-milling for AISI 316, AISI 422, TI-6AL-4V and Inconel 718 in a side-cutting configuration

International Nuclear Information System (INIS)

Shelton, Jonathan A; Shin, Yung C

2010-01-01

This paper is focused on numerical modeling and experimental evaluation of laser-assisted micro-milling (LAMM). An experimental setup consisting of a 25 W CO 2 laser, three-axis CNC linear stages and a high-speed spindle was used to implement the LAMM process. Micro-endmills between 100 and 300 µm in diameter were used to perform side-cutting operations with and without laser preheat on four materials: AISI 316, AISI 422, Ti-6Al-4V and Inconel 718. A three-dimensional transient finite-volume-based thermal model was used to analytically predict appropriate process parameters on the basis of material-removal temperatures. The effects of LAMM on the machined surface finish, edge burrs, tool wear and workpiece microstructure were evaluated experimentally.

17 CFR 166.2 - Authorization to trade.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Authorization to trade. 166.2 Section 166.2 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION CUSTOMER PROTECTION RULES § 166.2 Authorization to trade. No futures commission merchant, introducing broker or any of their...

Corrosion behavior of plasma sprayed hydroxyapatite and hydroxyapatite-silicon oxide coatings on AISI 304 for biomedical application

International Nuclear Information System (INIS)

Singh, Gurpreet; Singh, Hazoor; Sidhu, Buta Singh

2013-01-01

The objective of this study is to evaluate corrosion resistance of plasma sprayed hydroxyapatite (HA) and HA-silicon oxide (SiO 2 ) coated AISI 304 substrates. In HA-SiO 2 coatings, 10 wt% SiO 2 and 20 wt% SiO 2 was mixed with HA. The feedstock and coatings were characterized by X-ray diffraction and scanning electron microscopy/energy dispersive X-ray spectroscopy. The corrosion resistance was determined for the uncoated and coated samples. The corrosion resistance of the AISI 304 was found more after the deposition of the HA-SiO 2 coatings rather than HA coating and uncoated. All the coatings were crack free after 24 h dipping in Ringer's solution for electrochemical corrosion testing.

Effect of temperature and pressure on wear properties of ion nitrided AISI 316 and 409 stainless steels

International Nuclear Information System (INIS)

Fernandes, Frederico Augusto Pires; Heck, Stenio Cristaldo; Pereira, Ricardo Gomes; Casteletti, Luiz Carlos; Nascente, Pedro Augusto de Paula

2010-01-01

Stainless steels are widely used in chemical and other industries due to their corrosion resistance property. However, because of their low hardness and wear properties, their applications are limited. Many attempts have been made to increase the surface hardness of these materials by using plasma techniques. Plasma nitriding is distinguished by its effectiveness, and for presenting a relatively low cost and being a clean process, producing hard surface layers on stainless steels. Aiming to verify the influence of the temperature and pressure on the modified resultant layers, samples of AISI 316 and 409 stainless steels were plasma nitrided in two different temperatures (450 and 500°C) and pressures of 400, 500, and 600Pa for 5h. After the nitriding treatment, the layers were analyzed by means of optical microscopy and wear tests. Wear tests were conducted in a fixed-ball micro-wear machine without lubrication. After the plasma nitriding treatment on AISI 316 and 409 samples, homogeneous and continuous layers were produced and their thicknesses increased as the temperature increased, and as the pressure decreased. The nitriding treatment on the AISI 316 steel sample resulted on the formation of expanded austenite layers at 450°C, and chromium nitrides (CrN and Cr_2N) phases at 500°C. The nitriding treatment on AISI 409 sample yielded the formation of similar layers for both treatment temperatures; these layers constituted mainly by chromium (Cr_2N) and iron (Fe_2N, Fe3_N, and Fe_4N) nitrides. After the nitriding treatment, the AISI 316 steel sample presented higher wear resistance for lower temperature and pressure values. The increase on layer fragility, for higher temperature and pressure values can be responsible for this inverse tendency. The wear resistance of the nitrided AISI 409 sample followed a logic tendency: the harder the layer the better the performance, i.e. the performance was improved with the increase in both the temperature and pressure

Assessment of Retained Austenite in AISI D2 Tool Steel Using Magnetic Hysteresis and Barkhausen Noise Parameters

Science.gov (United States)

Kahrobaee, Saeed; Kashefi, Mehrdad

2015-03-01

Inaccurate heat treatment process could result in excessive amount of retained austenite, which degrades the mechanical properties, like strength, wear resistance, and hardness of cold work tool steel parts. Thus, to control the mechanical properties, quantitative measurement of the retained austenite is a critical step in optimizing the heat-treating parameters. X-ray diffraction method is the most frequently used technique for this purpose. This technique is, however, destructive and time consuming. Furthermore, it is not applicable to 100% quality inspection of industrial parts. In the present paper, the influence of austenitizing temperature on the retained austenite content and hardness of AISI D2 tool steel has been studied. Additionally, nondestructive magnetic hysteresis parameters of the samples including coercivity, magnetic saturation, and maximum differential permeability as well as their magnetic Barkhausen noise features (RMS peak voltage and peak position) have been investigated. The results revealed direct relations between magnetic saturation, differential permeability, and MBN peak amplitude with increasing austenitizing temperature due to the retained austenite formation. Besides, both parameters of coercivity and peak position had an inverse correlation with the retained austenite fraction.

Spin Waves in Ho2Co17

DEFF Research Database (Denmark)

Clausen, Kurt Nørgaard; Lebech, Bente

1980-01-01

Spin wave excitations in a single crystal of Ho2Co17 have been studied at 4.8 and 78 K. The results are discussed in terms of a linear spin wave model. At 78 K both ground state and excited state spin waves are observed.......Spin wave excitations in a single crystal of Ho2Co17 have been studied at 4.8 and 78 K. The results are discussed in terms of a linear spin wave model. At 78 K both ground state and excited state spin waves are observed....

PTEN drives Th17 cell differentiation by preventing IL-2 production.

Science.gov (United States)

Kim, Hyeong Su; Jang, Sung Woong; Lee, Wonyong; Kim, Kiwan; Sohn, Hyogon; Hwang, Soo Seok; Lee, Gap Ryol

2017-11-06

T helper 17 (Th17) cells are a CD4 + T cell subset that produces IL-17A to mediate inflammation and autoimmunity. IL-2 inhibits Th17 cell differentiation. However, the mechanism by which IL-2 is suppressed during Th17 cell differentiation remains unclear. Here, we show that phosphatase and tensin homologue (PTEN) is a key factor that regulates Th17 cell differentiation by suppressing IL-2 production. Th17-specific Pten deletion ( Pten fl/fl Il17a cre ) impairs Th17 cell differentiation in vitro and ameliorated symptoms of experimental autoimmune encephalomyelitis (EAE), a model of Th17-mediated autoimmune disease. Mechanistically, Pten deficiency up-regulates IL-2 and phosphorylation of STAT5, but reduces STAT3 phosphorylation, thereby inhibiting Th17 cell differentiation. PTEN inhibitors block Th17 cell differentiation in vitro and in the EAE model. Thus, PTEN plays a key role in Th17 cell differentiation by blocking IL-2 expression. © 2017 Kim et al.

Attenuation and immunogenicity of recombinant yellow fever 17D-dengue type 2 virus for rhesus monkeys

Directory of Open Access Journals (Sweden)

Galler R.

2005-01-01

Full Text Available A chimeric yellow fever (YF-dengue serotype 2 (dengue 2 virus was constructed by replacing the premembrane and envelope genes of the YF 17D virus with those from dengue 2 virus strains of Southeast Asian genotype. The virus grew to high titers in Vero cells and, after passage 2, was used for immunogenicity and attenuation studies in rhesus monkeys. Subcutaneous immunization of naive rhesus monkeys with the 17D-D2 chimeric virus induced a neutralizing antibody response associated with the protection of 6 of 7 monkeys against viremia by wild-type dengue 2 virus. Neutralizing antibody titers to dengue 2 were significantly lower in YF-immune animals than in YF-naive monkeys and protection against challenge with wild-type dengue 2 virus was observed in only 2 of 11 YF-immune monkeys. An anamnestic response to dengue 2, indicated by a sharp increase of neutralizing antibody titers, was observed in the majority of the monkeys after challenge with wild-type virus. Virus attenuation was demonstrated using the standard monkey neurovirulence test. The 17D-D2 chimera caused significantly fewer histological lesions than the YF 17DD virus. The attenuated phenotype could also be inferred from the limited viremias compared to the YF 17DD vaccine. Overall, these results provide further support for the use of chimeric viruses for the development of a new live tetravalent dengue vaccine.

PERFORMANCE STUDY ON AISI316 AND AISI410 USING DIFFERENT LAYERED COATED CUTTING TOOLS IN CNC TURNING

Directory of Open Access Journals (Sweden)

K. RAJA

2015-01-01

Full Text Available Stainless steel (SS is used for many commercial and industrial applications owing to its high resistance to corrosion. It is too hard to machine due to its high strength and high work hardening property. A surface property such as surface roughness (SR is critical to the function-ability of machined components. SS is generally regarded as more difficult to machine material and poor SR is obtained during machining. In this paper an attempt has been made to investigate the SR produced by CNC turning on austenitic stainless steel (AISI316 and martensitic stainless steel (AISI410 by different cases of coated cutting tool used at dry conditions. Multilayered coated with TiCN/Al2O3, multilayered coated with Ti(C, N, B and single layered coated with TiAlN coated cutting tools are used. Experiments were carried out by using Taguchi’s L27 orthogonal array. The effect of cutting parameters on SR is evaluated and optimum cutting conditions for minimizing the SR are determined. Analysis of variance (ANOVA is used for identifying the significant parameters affecting the responses. Confirmation experiments are conducted to validate the results obtained from optimization.

Investigation on AISI 304 austenitic stainless steel to AISI 4140 low alloy steel dissimilar joints by gas tungsten arc, electron beam and friction welding

International Nuclear Information System (INIS)

Arivazhagan, N.; Singh, Surendra; Prakash, Satya; Reddy, G.M.

2011-01-01

Research highlights: → Beneficial effects of FRW, GTAW and EBW joints of dissimilar AISI 304 and AISI 4140 materials. → Comparative study of FRW, GTAW and EBW joints on mechanical properties. → SEM/EDAX, XRD analysis on dissimilar AISI 304 and AISI 4140 materials. -- Abstract: This paper presents the investigations carried out to study the microstructure and mechanical properties of AISI 304 stainless steel and AISI 4140 low alloy steel joints by Gas Tungsten Arc Welding (GTAW), Electron Beam Welding (EBW) and Friction Welding (FRW). For each of the weldments, detailed analysis was conducted on the phase composition, microstructure characteristics and mechanical properties. The results of the analysis shows that the joint made by EBW has the highest tensile strength (681 MPa) than the joint made by GTAW (635 Mpa) and FRW (494 Mpa). From the fractographs, it could be observed that the ductility of the EBW and GTA weldment were higher with an elongation of 32% and 25% respectively when compared with friction weldment (19%). Moreover, the impact strength of weldment made by GTAW is higher compared to EBW and FRW.

Synthesis of [2,4-3H] 17β-dihydroequilin sulfate

International Nuclear Information System (INIS)

Bhavnani, B.R.

1994-01-01

[2,4- 3 H] 17β-dihydroequilin-3-sulfate ammonium salt suitable for in vivo pharmacokinetic studies was synthesized from [2,4- 3 H] equilin. Sulfation of [2,4- 3 H] equilin with pyridine-chlorosulfonic acid mixture gave in high yields [2,4- 3 H] equilin sulfate, which was then reduced with sodium borohydride to yield [2,4- 3 H] 17β-dihydroequilin sulfate. The reduction was sterospecific and no 17α-reduced products were formed. (author)

Sub-surface Fatigue Crack Growth at Alumina Inclusions in AISI 52100 Roller Bearings

DEFF Research Database (Denmark)

Cerullo, Michele

2014-01-01

Sub-surface fatigue crack growth at non metallic inclusions is studied in AISI 52100 bearing steel under typical rolling contact loads. A first 2D plane strain finite element analysis is carried out to compute the stress history in the innner race at a characteristic depth, where the Dang Van...... damage factor is highest. Subsequently the stress history is imposed as boundary conditions in a periodic unit cell model, where an alumina inclusion is embedded in a AISI 52100 matrix. Cracks are assumed to grow radially from the inclusion under cyclic loading. The growth is predicted by means...

Termo-Reaktif Difüzyon Tekniği ile Cr-Al-N Kaplanmış AISI D2 Çeliğinin Aşınma Davranışı

OpenAIRE

KILINÇ, Bülent; ÇEĞİL, Özkan; ŞEN, Uğur; ŞEN, Şaduman

2014-01-01

In this work, the wear test of uncoated, nitrided, chromium aluminum nitride coated AISI D2 cold work tool steel against silicon nitride ball realized at 0.1 m/s sliding speeds and under the loads of 2.5N, 5N and 10N.Steel samples were nitrided at 575 °C for 8 h in the first step of the coating process, and then chromium aluminum nitride coating was performed thermo-reactive deposition technique (TRD) in a powder mixture consisting of ferro-chromium, aluminum, ammonium chloride, alumina and n...

Description and crystal structure of albrechtschraufite, MgCa{sub 4}F{sub 2}[UO{sub 2}(CO{sub 3}){sub 3}]{sub 2}.17-18H{sub 2}O

Energy Technology Data Exchange (ETDEWEB)

Mereiter, K. [Vienna Univ. of Technology (Austria). Inst. of Chemical Technologies and Analytics

2013-04-15

Albrechtschraufite, MgCa{sub 4}F{sub 2}[UO{sub 2}(CO{sub 3}){sub 3}]{sub 2}.17-18H{sub 2}O, triclinic, space group P anti 1, a = 13.569(2), b = 13.419(2), c = 11.622(2) Aa, α = 115.82(1), β = 107.61(1), γ = 92.84(1) (structural unit cell, not reduced), V = 1774.6(5) Aa{sup 3}, Z = 2, Dc = 2.69 g/cm{sup 3} (for 17.5 H{sub 2}O), is a mineral that was found in small amounts with schroeckingerite, NaCa{sub 3}F[UO{sub 2}(CO{sub 3}){sub 3}](SO{sub 4}).10H{sub 2}O, on a museum specimen of uranium ore from Joachimsthal (Jachymov), Czech Republic. The mineral forms small grain-like subhedral crystals (= 0.2 mm) that resemble in appearance liebigite, Ca{sub 2}[UO{sub 2}(CO{sub 3}){sub 3}]. ∝ 11H{sub 2}O. Colour pale yellow-green, luster vitreous, transparent, pale bluish green fluorescence under ultraviolet light. Optical data: Biaxial negative, nX = 1.511(2), nY = 1.550(2), nZ = 1.566(2), 2V = 65(1) (λ = 589 nm), r < v weak. After qualitative tests had shown the presence of Ca, U, Mg, CO{sub 2} and H{sub 2}O, the chemical formula was determined by a crystal structure analysis based on X-ray four-circle diffractometer data. The structure was later on refined with data from a CCD diffractometer to R1 = 0.0206 and wR2 = 0.0429 for 9,236 independent observed reflections. The crystal structure contains two independent [UO{sub 2}(CO{sub 3}){sub 3}]{sup 4-} anions of which one is bonded to two Mg and six Ca while the second is bonded to only one Mg and three Ca. Magnesium forms a MgF{sub 2}(O{sub carbonate}){sub 3}(H{sub 2}O) octahedron that is linked via the F atoms with three Ca atoms so as to provide each F atom with a flat pyramidal coordination by one Mg and two Ca. Calcium is 7- and 8-coordinate forming CaFO{sub 6}, CaF{sub 2}O{sub 2}(H{sub 2}O){sub 4}, CaFO{sub 3}(H{sub 2}O){sub 4} and CaO{sub 2}(H{sub 2}O){sub 6} coordination polyhedra. The crystal structure is built up from MgCa{sub 3}F{sub 2}[UO{sub 2}(CO{sub 3}){sub 3}].8H{sub 2}O layers parallel to (001) which

Electrochemical testing of passivity state and corrosion resistance of supermartensitic stainless steels

Directory of Open Access Journals (Sweden)

S. Lasek

2010-01-01

Full Text Available On low interstitial - supermartensitic stainless steels (X1CrNiMo 12-5-1, X2CrNiMo 13-6-2, X1CrNiMo 12-6-2 the electrochemical potentiodynamic polarization tests were carried out and the passive state stability and localized corrosion resistance were compared and evaluated. The effect of quenching and tempering as well as the changes in microstructure on polarisation curves and corrosion properties at room temperature were established. Small differences in chemical composition of steels were also registered on their corrosion parameters changes and resistance.

A gene-protein assay for human epidermal growth factor receptor 2 (HER2: brightfield tricolor visualization of HER2 protein, the HER2 gene, and chromosome 17 centromere (CEN17 in formalin-fixed, paraffin-embedded breast cancer tissue sections

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Nitta Hiroaki

2012-05-01

Full Text Available Abstract Background The eligibility of breast cancer patients for human epidermal growth factor receptor 2 (HER2-directed therapies is determined by the HER2 gene amplification and/or HER2 protein overexpression status of the breast tumor as determined by in situ hybridization (ISH or immunohistochemistry (IHC, respectively. Our objective was to combine the US Food and Drug Administration (FDA-approved HER2 & chromosome 17 centromere (CEN17 brightfield ISH (BISH and HER2 IHC assays into a single automated HER2 gene-protein assay allowing simultaneous detection of all three targets in a single tissue section. Methods The HER2 gene-protein assay was optimized using formalin-fixed, paraffin-embedded (FFPE samples of the xenograft tumors MCF7 [HER2 negative (non-amplified gene, protein negative] and Calu-3 [HER2 positive (amplified gene, protein positive]. HER2 IHC was performed using a rabbit monoclonal anti-HER2 antibody (clone 4B5 and a conventional 3,3'-diaminobenzidine IHC detection. The HER2 & CEN17 BISH signals were visualized using horseradish peroxidase-based silver and alkaline phosphatase-based red detection systems, respectively with a cocktail of 2,4-dinitrophenyl-labeled HER2 and digoxigenin-labeled CEN17 probes. The performance of the gene-protein assay on tissue microarray slides containing 189 randomly selected FFPE clinical breast cancer tissue cores was compared to that of the separate HER2 IHC and HER2 & CEN17 BISH assays. Results HER2 protein detection was optimal when the HER2 IHC protocol was used before (rather than after the BISH protocol. The sequential use of HER2 IHC and HER2 & CEN17 BISH detection steps on FFPE xenograft tumor sections appropriately co-localized the HER2 protein, HER2 gene, and CEN17 signals after mitigating the silver background staining by using a naphthol phosphate-containing hybridization buffer for the hybridization step. The HER2 protein and HER2 gene status obtained using the multiplex HER2 gene

Investigations on the creep-rupture behaviour of the austenitic stainless steel AISI 316 NET

International Nuclear Information System (INIS)

Schirra, M.; Ritter, B.

1988-12-01

The report describes the creep-rupture tests carried out with a 17/13/2 CrNiMo-steel in the frame of the German-Spanish collaboration (KfK-CIEMAT). The material studied is the austenitic steel AISI 316(L) selected as potential first-wall material for NET (Next European Torus). The test programme on base material with a NET specified batch encompasses until now in the temperature range 500-750 0 C the rupture-time-range till 20 000 h. The results permit statements to the creep- and creep-rupture behaviour and ductility. Metallography examinations give information about fracture behaviour and demonstrate the complex precipitation happening. The results are compared with the literature and own test results from two batches of the Fast-Breeder-Program. (orig.) [de

2,2-Dimethyl-2,3-dihydropyrano[2,3-a]carbazol-4(11H-one

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Makuteswaran Sridharan

2008-11-01

Full Text Available The title compound, C17H15NO2, was prepared from 1-hydroxycarbazole and 3,3-dimethylacrylic acid with a mixture of AlCl3 and POCl3 as the cyclization catalyst. Owing to the presence of the –CMe2– group, the molecule is not quite planar. In the crystal structre, strong N—H...O hydrogen bonds and weaker C—H...π interactions occur, and a slipped π–π stacking interaction [centroid–centroid separation = 3.8425 (8 Å] is also observed.

Attention Deficit Hyperactivity Disorder Symptoms and Psychosis in 22q11.2 Deletion Syndrome.

Science.gov (United States)

Niarchou, Maria; Calkins, Monica E; Moore, Tyler M; Tang, Sunny X; McDonald-McGinn, Donna M; Zackai, Elaine H; Emanuel, Beverly S; Gur, Ruben C; Gur, Raquel E

2017-10-10

22q11.2 Deletion Syndrome (22q11.2DS) is associated with increased risk for schizophrenia in adulthood while Attention Deficit Hyperactivity Disorder (ADHD) is the most prevalent diagnosis in childhood. Inattention symptoms are pronounced in 22q11.2DS and given that attentional impairment is a core feature of schizophrenia, inattention symptoms may reflect underlying ADHD, psychosis, or both. We investigate whether inattention is associated with psychosis in 22q11.2DS and in other groups at risk for psychosis but without the deletion (ND) (idiopathic clinical risk and first degree family members of individuals with schizophrenia). One hundred thirty-seven individuals with 22q11.2DS (mean age: 14.0), 84 ND individuals with subthreshold psychosis (mean age: 16.9) and 31 ND individuals with family history of psychosis (mean age: 17.0) were included in the study. Psychopathology was assessed using research diagnostic assessments. ADHD total symptoms were associated with overall levels of subthreshold psychosis symptoms in 22q11.2DS (β = .8, P = .04). Inattention symptoms were specifically associated with positive (β = .5, P = .004), negative (β = .5, P = .03), and disorganized (β = .5, P hyperactivity-impulsivity symptoms were associated with disorganized symptoms (β = .5, P = .01). The prevalence of ADHD inattention symptoms was higher in 22q11.2DS with subthreshold psychosis compared to ND individuals with subthreshold psychosis (P < .001), even when adjusting for cognitive impairment and overall psychopathology. The pattern was similar when comparing individuals with 22q11.2DS and ND individuals with family history of psychosis. This is the first study to examine the associations between ADHD symptoms and psychosis in 22q11.2DS. Our findings support a potentially important role of ADHD inattention symptoms in psychosis in 22q11.2DS. © The Author 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights

Systematic modulation and enhancement of CO{sub 2} : N{sub 2} selectivity and water stability in an isoreticular series of bio-MOF-11 analogues

Energy Technology Data Exchange (ETDEWEB)

Li, Tao; Chen, De-Li; Sullivan, Jeanne E.; Kozlowski, Mark T.; Johnson, J Karl; Rosi, Nathaniel L.

2013-02-01

An isoreticular series of cobalt-adeninate bio-MOFs (bio-MOFs 11-14) is reported. The pores of bio-MOFs 11-14 are decorated with acetate, propionate, butyrate, and valerate, respectively. The nitrogen (N{sub 2}) and carbon dioxide (CO{sub 2}) adsorption properties of these materials are studied and compared. The isosteric heats of adsorption for CO{sub 2} are calculated, and the CO{sub 2}:N{sub 2} selectivities for each material are 10 determined. As the lengths of the aliphatic chains decorating the pores in bio-MOFs 11-14 increase, the BET surface areas decrease from 1148 m{sup 2}/g to 17 m{sup 2}/g while the CO{sub 2}:N{sub 2} selectivities predicted from ideal adsorbed solution theory at 1 bar and 273 K for a 10:90 CO{sub 2}:N{sub 2} mixture range from 73:1 for bio-MOF-11 to 123:1 for bio-MOF-12 and finally to 107:1 for bio-MOF-13. At 298 K, the selectivities are 43:1 for bio-MOF-11, 52:1 for bio-MOF-12, and 40:1 for bio-MOF-13. Additionally, it is shown that 15 bio-MOF-14 exhibits a unique molecular sieving property that allows it to adsorb CO{sub 2} but not N{sub 2} at 273 and 298 K. Finally, the water stability of bio-MOFs 11-14 increases with increasing aliphatic chain length. Bio-MOF-14 exhibits no loss of crystallinity or porosity after soaking in water for one month.

The effect of surface nanocrystallization on plasma nitriding behaviour of AISI 4140 steel

International Nuclear Information System (INIS)

Li Yang; Wang Liang; Zhang Dandan; Shen Lie

2010-01-01

A plastic deformation surface layer with nanocrystalline grains was produced on AISI 4140 steel by means of surface mechanical attrition treatment (SMAT). Plasma nitriding of SMAT and un-SMAT AISI 4140 steel was carried out by a low-frequency pulse excited plasma unit. A series of nitriding experiments has been conducted at temperatures ranging from 380 to 500 deg. C for 8 h in an NH 3 gas. The samples were characterized using X-ray diffraction, scanning electron microscopy, optical microscopy and Vickers microhardness tester. The results showed that a much thicker compound layer with higher hardness was obtained for the SMAT samples when compared with un-SMAT samples after nitriding at the low temperature. In particular, plasma nitriding SMAT AISI 4140 steel at 380 deg. C for 8 h can produced a compound layer of 2.5 μm thickness with very high hardness on the surface, which is similar to un-SMAT samples were plasma nitrided at approximately 430 deg. C within the same time.

The effect of surface nanocrystallization on plasma nitriding behaviour of AISI 4140 steel

Science.gov (United States)

Li, Yang; Wang, Liang; Zhang, Dandan; Shen, Lie

2010-11-01

A plastic deformation surface layer with nanocrystalline grains was produced on AISI 4140 steel by means of surface mechanical attrition treatment (SMAT). Plasma nitriding of SMAT and un-SMAT AISI 4140 steel was carried out by a low-frequency pulse excited plasma unit. A series of nitriding experiments has been conducted at temperatures ranging from 380 to 500 °C for 8 h in an NH 3 gas. The samples were characterized using X-ray diffraction, scanning electron microscopy, optical microscopy and Vickers microhardness tester. The results showed that a much thicker compound layer with higher hardness was obtained for the SMAT samples when compared with un-SMAT samples after nitriding at the low temperature. In particular, plasma nitriding SMAT AISI 4140 steel at 380 °C for 8 h can produced a compound layer of 2.5 μm thickness with very high hardness on the surface, which is similar to un-SMAT samples were plasma nitrided at approximately 430 °C within the same time.

Gradient microstructure and microhardness in a nitrided 18CrNiMo7-6 gear steel

Science.gov (United States)

Yang, R.; Wu, G. L.; Zhang, X.; Fu, W. T.; Huang, X.

2017-07-01

A commercial gear steel (18CrNiMo7-6) containing a tempered martensite structure was nitrided using a pressurized gas nitriding process under a pressure of 5 atm at 530 °C for 5 hours. The mechanical properties and microstructure of the nitrided sample were characterized by Vickers hardness measurements, X-ray diffraction, and backscatter electron imaging in a scanning electron microscope. A micro-hardness gradient was identified over a distance of 500 μm with hardness values of 900 HV at the top surface and 300 HV in the core. This micro-hardness gradient corresponds to a gradient in the microstructure that changes from a nitride compound layer at the top surface (∼ 20 μm thick) to a diffusion zone with a decreasing nitrogen concentration and precipitate density with distance from the surface, finally reaching the core matrix layer with a recovered martensite structure.

Long-range effect in nitrogen ion-implanted AISI 316L stainless steel

Energy Technology Data Exchange (ETDEWEB)

Budzynski, P., E-mail: p.budzynski@pollub.pl

2015-01-01

The effect of nitrogen ion implantation on AISI 316L stainless steel was investigated. The microstructure and composition of an N implanted layer were studied by RBS, GIXRD, SEM, and EDX measurements. Friction and wear tests were also performed. The discrepancy between the measured and calculated stopped ion maximum range does not exceed 0.03 μm. After nitrogen implantation with a fluence of 5 × 10{sup 17} ion/cm{sup 2}, additional phases of expanded austenite were detected. At a 5-fold larger depth than the maximum ion range, improvement in the coefficient of friction and wear was detected. We have shown, for the first time, the long-range effect in tribological investigations. The long-range effect is caused by movement of not only defects along the depth of the sample, as assumed so far, but also nitrogen atoms.

[Studies on the tolerance of the organism to X 5 CrNiMo 18.10 steel (Königsee). II. Light microscopic studies of the surrounding tissue of metal implants (X 5 CrNiMo 18.10 steel) in guinea pigs].

Science.gov (United States)

Höhndorf, H; Drössler, K; Stiehl, P

1977-06-01

The tissue around X 5 CrNiMo 18.10-steel implantates with different surfaces was examined in 72 guinea-pigs. Aside from controls, these animals were preoperatively sensibilized against chromium and nickel. The results can be summarized since the histologic findings showed no different peculiarities. The authors describe an intussusception of the implantate in connective tissue which evidently depends on time and surface. Further the spreading of alien material in the surrounding of the implantate, and morphologic findings are reported. The morphologic evidences are described and discussed in detail, since they are interpreted as signs of cell-mediated immune reactions. The presence of lymphocytes, lymphoblasts, histiocytes (mostly carrying alien material), and granulocytes, as well as proliferations at the arterioles suggest an overlapping of immune reactions.

Resistencia al desgaste de recubrimientos Fe-Nb-Cr-W, Nb, AISI 1020 y AISI 420 producidos por proyección térmica por arco eléctrico

Directory of Open Access Journals (Sweden)

López-Covaleda, E. A.

2013-10-01

Full Text Available The commercial materials 140MXC (with iron, tungsten, chrome, niobium, 530AS (AISI 1015 steel and 560AS (AISI 420 steel on AISI 4340 steel were deposited using thermal spray with arc. The aim of work was to evaluate the best strategy abrasive wear resistance of the system coating-substrate using the following combinations: (1 homogeneous coatings and (2 coatings depositing simultaneously 140MXC + 530AS and 140MXC + 560AS. The coatings microstructure was characterized using Optical microscopy, Scanning electron microscopy and Laser confocal microscopy. The wear resistance was evaluated through dry sand rubber wheel test (DSRW. We found that the wear resistance depends on the quantity of defects and the mechanical properties like hardness. For example, the softer coatings have the biggest wear rates and the failure mode was characterized by plastic deformation caused by particles indentation, and the other hand the failure mode at the harder materials was grooving. The details and wear mechanism of the coatings produced are described in this investigation.Mediante proyección térmica de arco eléctrico fueron depositados tres materiales comercialmente conocidos como: 140MXC (a base de hierro, wolframio, cromo y niobio, 530AS (acero AISI 1020 y 560AS (acero AISI 420, sobre acero AISI 4340. Con el objetivo de evaluar la mejor estrategia para incrementar la resistencia al desgaste abrasivo, los recubrimientos fueron depositados de dos formas: (1 monocapas homogéneas de cada material y (2 recubrimientos depositando con alambres disimiles de 140MXC + 530AS y 140MXC + 560AS. Los recubrimientos fueron caracterizados microestructuralmente mediante Difracción de rayos X, Microscopía óptica, Microscopía láser confocal y Microscopía electrónica de barrido. La evaluación de la resistencia al desgaste abrasivo se realizó mediante ensayo con arena seca y rueda de caucho (DSRW. Se encontró que la resistencia al desgaste depende entre otras de las

A genome-wide association meta-analysis identifies a novel locus at 17q11.2 associated with sporadic amyotrophic lateral sclerosis

Science.gov (United States)

Fogh, Isabella; Ratti, Antonia; Gellera, Cinzia; Lin, Kuang; Tiloca, Cinzia; Moskvina, Valentina; Corrado, Lucia; Sorarù, Gianni; Cereda, Cristina; Corti, Stefania; Gentilini, Davide; Calini, Daniela; Castellotti, Barbara; Mazzini, Letizia; Querin, Giorgia; Gagliardi, Stella; Del Bo, Roberto; Conforti, Francesca L.; Siciliano, Gabriele; Inghilleri, Maurizio; Saccà, Francesco; Bongioanni, Paolo; Penco, Silvana; Corbo, Massimo; Sorbi, Sandro; Filosto, Massimiliano; Ferlini, Alessandra; Di Blasio, Anna M.; Signorini, Stefano; Shatunov, Aleksey; Jones, Ashley; Shaw, Pamela J.; Morrison, Karen E.; Farmer, Anne E.; Van Damme, Philip; Robberecht, Wim; Chiò, Adriano; Traynor, Bryan J.; Sendtner, Michael; Melki, Judith; Meininger, Vincent; Hardiman, Orla; Andersen, Peter M.; Leigh, Nigel P.; Glass, Jonathan D.; Overste, Daniel; Diekstra, Frank P.; Veldink, Jan H.; van Es, Michael A.; Shaw, Christopher E.; Weale, Michael E.; Lewis, Cathryn M.; Williams, Julie; Brown, Robert H.; Landers, John E.; Ticozzi, Nicola; Ceroni, Mauro; Pegoraro, Elena; Comi, Giacomo P.; D'Alfonso, Sandra; van den Berg, Leonard H.; Taroni, Franco; Al-Chalabi, Ammar; Powell, John; Silani, Vincenzo; Brescia Morra, Vincenzo; Filla, Alessandro; Massimo, Filosto; Marsili, Angela; Viviana, Pensato; Puorro, Giorgia; La Bella, Vincenzo; Logroscino, Giancarlo; Monsurrò, Maria Rosaria; Quattrone, Aldo; Simone, Isabella Laura; Ahmeti, Kreshnik B.; Ajroud-Driss, Senda; Armstrong, Jennifer; Birve, Anne; Blauw, Hylke M.; Bruijn, Lucie; Chen, Wenjie; Comeau, Mary C.; Cronin, Simon; Soraya, Gkazi Athina; Grab, Josh D.; Groen, Ewout J.; Haines, Jonathan L.; Heller, Scott; Huang, Jie; Hung, Wu-Yen; Jaworski, James M.; Khan, Humaira; Langefeld, Carl D.; Marion, Miranda C.; McLaughlin, Russell L.; Miller, Jack W.; Mora, Gabriele; Pericak-Vance, Margaret A.; Rampersaud, Evadnie; Siddique, Nailah; Siddique, Teepu; Smith, Bradley N.; Sufit, Robert; Topp, Simon; Vance, Caroline; van Vught, Paul; Yang, Yi; Zheng, J.G.

2014-01-01

Identification of mutations at familial loci for amyotrophic lateral sclerosis (ALS) has provided novel insights into the aetiology of this rapidly progressing fatal neurodegenerative disease. However, genome-wide association studies (GWAS) of the more common (∼90%) sporadic form have been less successful with the exception of the replicated locus at 9p21.2. To identify new loci associated with disease susceptibility, we have established the largest association study in ALS to date and undertaken a GWAS meta-analytical study combining 3959 newly genotyped Italian individuals (1982 cases and 1977 controls) collected by SLAGEN (Italian Consortium for the Genetics of ALS) together with samples from Netherlands, USA, UK, Sweden, Belgium, France, Ireland and Italy collected by ALSGEN (the International Consortium on Amyotrophic Lateral Sclerosis Genetics). We analysed a total of 13 225 individuals, 6100 cases and 7125 controls for almost 7 million single-nucleotide polymorphisms (SNPs). We identified a novel locus with genome-wide significance at 17q11.2 (rs34517613 with P = 1.11 × 10−8; OR 0.82) that was validated when combined with genotype data from a replication cohort (P = 8.62 × 10−9; OR 0.833) of 4656 individuals. Furthermore, we confirmed the previously reported association at 9p21.2 (rs3849943 with P = 7.69 × 10−9; OR 1.16). Finally, we estimated the contribution of common variation to heritability of sporadic ALS as ∼12% using a linear mixed model accounting for all SNPs. Our results provide an insight into the genetic structure of sporadic ALS, confirming that common variation contributes to risk and that sufficiently powered studies can identify novel susceptibility loci. PMID:24256812

1,1′-Binaphthyl-2,2′-dicarboxylic acid–urea (1/1

Directory of Open Access Journals (Sweden)

Edwin Weber

2008-10-01

Full Text Available In the title co-crystal, C22H14O4·CH4N2O, the 1,1′-binaphthyl-2,2′-dicarboxylic acid (BNDA and urea molecules are connected via a system of hydrogen bonds into a chiral two-dimensional polymeric structure parallel to the (001 plane. As the crystal is centrosymmetric, it consists of alternately stacked BNDA–urea layers of opposite chirality. The urea H atoms trans to the C=O group are bonded in a chelating mode [R12(6] to the carbonyl O atom from one of the carboxylic acid groups which, in turn, acts as the donor of an O—H...O hydrogen bond to another urea molecule. The [010] chains thus formed are further connected via an R22(8 hydrogen-bond motif formed between urea and the second carboxylic acid group of BNDA.

Radiosynthesis and ex vivo evaluation of (R)-(-)-2-chloro-N-[1-11C-propyl]n-propylnorapomorphine

International Nuclear Information System (INIS)

Palner, Mikael; McCormick, Patrick; Gillings, Nic; Begtrup, Mikael; Wilson, Alan A.; Knudsen, Gitte M.

2010-01-01

Introduction: Several dopamine D 2 agonist radioligands have been used with positron emission tomography (PET), including [ 11 C-]-(-)-MNPA, [ 11 C-]-(-)-NPA and [ 11 C]-(+)-PHNO. These radioligands are considered particularly powerful for detection of endogenous dopamine release, but they either provide PET brain images with limited contrast or have affinity for both D 2 and D 3 receptors. We here present the carbon-11 radiolabeling and ex vivo evaluation of 2-Cl-(-)-NPA, a novel PET-tracer candidate with high in vitro D 2 /D 3 selectivity. Methods: 2-Cl-[ 11 C]-(-)-NPA and [ 11 C]-(-)-NPA were synthesized by a two step N-acylation-reduction process using [ 11 C]-propionyl chloride. Awake rats were injected with either tracer, via the tail vein. The rats were decapitated at various times, the brains were removed and quickly dissected, and plasma metabolites were measured. Radioligand specificity, and P-glycoprotein involvement in brain uptake, was also assessed. Results: 2-Cl-[ 11 C]-(-)-NPA and [ 11 C]-(-)-NPA were produced in high specific activity and purity. 2-Cl-[ 11 C]-(-)-NPA accumulated slower in the striatum than [ 11 C]-(-)-NPA, reaching maximum concentrations after 30 min. The maximal striatal uptake of 2-Cl-[ 11 C]-(-)-NPA (standard uptake value 0.72±0.24) was approximately half that of [ 11 C]-(-)-NPA (standard uptake value 1.37±0.18). Nonspecific uptake was similar for the two compounds. 2-Cl-[ 11 C]-(-)-NPA was metabolized quickly, leaving only 17% of the parent compound in the plasma after 30 min. The specific binding of 2-Cl-[ 11 C]-(-)-NPA was completely blocked and inhibition of P-glycoprotein did not alter the brain uptake. Conclusion: Ex vivo experiments showed, despite a favorable D 2 /D 3 selectivity, that 2-Cl-[ 11 C]-(-)-NPA is inferior to [ 11 C]-(-)-NPA as a PET tracer in rat, because of slower brain uptake and lower specific to nonspecific binding ratio.

17 CFR 8.11 - Notice of charges.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Notice of charges. 8.11 Section 8.11 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION EXCHANGE PROCEDURES FOR DISCIPLINARY, SUMMARY, AND MEMBERSHIP DENIAL ACTIONS Disciplinary Procedure § 8.11 Notice of...

Magnetic phase transitions in R2Fe17 compounds under pressure

International Nuclear Information System (INIS)

Arnold, Z.; Kamarad, J.

1994-01-01

The effect of the pressure up to 1.4 GPa on the Curie temperature T c in the R 2 Fe 17 intermetallics with R = Nd, Er and Y was measured using a low field susceptibility technique. The identical character of the temperature dependence of susceptibility χ(T) of the R 2 Fe 17 intermetallics observed at ambient pressure (sharp step-like drop at T c ) is preserved at high pressures only in the case of Nd 2 Fe 17 . Pronounced broadening and splitting of the sharp drop of χ(T) was observed in Er 2 Fe 17 and Y 2 Fe 17 respectively. The initial pressure slopes of dTc/dp are large and negative for all studied compounds, having nearly the same values (dTc/dp = -36K/GPa for Nd 2 Fe 17 compound). The results are discussed from the point of view of the sensitivity of T c on the crystal structure, the number of nearest neighbors of Fe atoms and the possible effect of disordered structures in the R 2 Fe 17 intermetallics

17AAG-induced internalisation of HER2-specific Affibody molecules.

Science.gov (United States)

Göstring, Lovisa; Lindegren, Sture; Gedda, Lars

2016-10-01

The geldanamycin derivative 17-allylamino-17-demethoxygeldanamycin (17-AAG) is known to induce internalisation and degradation of the otherwise internalisation-resistant human epidermal growth factor receptor 2 (HER2) receptor. In the present study, 17-AAG was used to increase internalisation of the HER2-specific Affibody molecule ABY-025. The cellular redistribution of halogen-labelled 211 At-ABY-025 and radiometal-labelled 111 In-ABY-025 following treatment with 17-AAG was studied. 17-AAG treatment of SKOV-3 human ovarian carcinoma and SKBR-3 human breast carcinoma cells to some extent shifted the localisation of 111 In-ABY-025 from the cell surface to intracellular compartments in the two cell lines. ABY-025 labelled with the high-linear energy transfer α emitter 211 At was also internalised to a higher degree; however, due to its physiological properties, this nuclide was excreted faster. The results indicate that 17-AAG may be used to facilitate cell-specific intracellular localisation of a suitable cytotoxic or radioactive agent coupled to ABY-025 in HER2-overexpressing cells.

Effect of mechanical activation on jell boronizing treatment of the AISI 4140

Science.gov (United States)

Yılmaz, S. O.; Karataş, S.

2013-06-01

The article presents the effect of mechanical activation on the growth kinetics of boride layer of boronized AISI 4140 steel. The samples were boronized by ferroboron + (SiO2-Na2O) powders for 873-1173 K temperature and 2, 4, 6 and 8 h times, respectively. The morphology and types of borides formed on the surface of AISI 4140 steel substrate were analyzed. Layer growth kinetics were analyzed by measuring the extent of penetration of FeB and Fe2B sublayers as function of treatment time and temperature in the range of 873-1173 K. High diffusivity was obtained by creating a large number of defects through mechanical activation in the form of nanometer sized crystalline particles through the repeated fracturing and cold-welding of the powder particles, and a depth of 100 μm was found in the specimen borided by the 2 h MA powders, for 4 h and 1073 K, where 2000-2350 HV were measured. Consequently, the application conditions of boronizing were improved by usage of mechanical activation. The preferred Fe2B boride without FeB could be formed in the boride layer under 973 K boronizing temperature by mechanically activated by ferroboron + sodium silicate powder mixture due to the decrease of the activation energy.

44 CFR 11.17 - Referral to Department of Justice.

Science.gov (United States)

2010-10-01

... Justice. 11.17 Section 11.17 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY... Referral to Department of Justice. When Department of Justice approval or consultation is required under § 11.16, the referral or request shall be transmitted to the Department of Justice by the Chief Counsel...

Plasma nitriding process by direct current glow discharge at low temperature increasing the thermal diffusivity of AISI 304 stainless steel

Energy Technology Data Exchange (ETDEWEB)

Prandel, L. V.; Somer, A.; Assmann, A.; Camelotti, F.; Costa, G.; Bonardi, C.; Jurelo, A. R.; Rodrigues, J. B.; Cruz, G. K. [Universidade Estadual de Ponta Grossa, Grupo de Espectroscopia Optica e Fotoacustica de Materiais, Departamento de Fisica, Av. Carlos Cavalcanti, 4748, CEP 84030-900, Ponta Grossa, PR (Brazil)

2013-02-14

This work reports for the first time on the use of the open photoacoustic cell technique operating at very low frequencies and at room temperature to experimentally determine the thermal diffusivity parameter of commercial AISI304 stainless steel and AISI304 stainless steel nitrided samples. Complementary measurements of X-ray diffraction and scanning electron microscopy were also performed. The results show that in standard AISI 304 stainless steel samples the thermal diffusivity is (4.0 {+-} 0.3) Multiplication-Sign 10{sup -6} m{sup 2}/s. After the nitriding process, the thermal diffusivity increases to the value (7.1 {+-} 0.5) Multiplication-Sign 10{sup -6} m{sup 2}/s. The results are being associated to the diffusion process of nitrogen into the surface of the sample. Carrying out subsequent thermal treatment at 500 Degree-Sign C, the thermal diffusivity increases up to (12.0 {+-} 2) Multiplication-Sign 10{sup -6} m{sup 2}/s. Now the observed growing in the thermal diffusivity must be related to the change in the phases contained in the nitrided layer.

Experimental investigation on mechanical and microstructural properties of AISI 304 to Cu joints by CO2 laser

Directory of Open Access Journals (Sweden)

Bikash Ranjan Moharana

2016-06-01

Full Text Available Aim of the present work is to investigate mechanical and metallurgical characteristics of continuous wave CO2 laser welded dissimilar couple of AISI 304 stainless steel and commercially pure copper sheets in autogenous mode. Metallurgical analysis of the fusion zone has been done to understand the mixing and solidification behavior. Macroscopic examination has been carried out to observe the macro-segregation pattern of Cu, Fe and Cr rich phases in different zones, and the thickness of HAZ was found to be around 10 µm. The micro-channels formed from the steel side to weld pool describe that the copper solidifies first and provides the nucleation surface for the residual melt to grow. These tubular micro-channels formed may be due to carbide precipitation. The EDS analysis conforms the well mixing of SS and Cu inside the weld pool. The mechanical properties in terms of tensile stress found up to 201 MPa and the fracture are obtained outside the weld zone. Microhardness measurements over the fusion zone have been done to understand the keyhole growth and quenching, solidification sequence and stress distribution over the full area.

45 CFR 1626.11 - H-2 agricultural workers.

Science.gov (United States)

2010-10-01

...) Other employment rights as provided in the worker's specific contract under which the nonimmigrant... 45 Public Welfare 4 2010-10-01 2010-10-01 false H-2 agricultural workers. 1626.11 Section 1626.11... ON LEGAL ASSISTANCE TO ALIENS § 1626.11 H-2 agricultural workers. (a) Nonimmigrant agricultural...

Deletion in the uridine diphosphate glucuronyltransferase 2B17 gene is associated with delayed pubarche in healthy boys

DEFF Research Database (Denmark)

Mouritsen, Annette Korsholm; Busch, Alexander Siegfried; Aksglaede, Lise

2018-01-01

(del/ins) vs. 12.06 years (11.79-12.33) in boys with the wildtype genotype (ins/ins) (p=0.029, corrected for BMI z-score). The effect accounted for 0.34 years delay per allele (95%CI: 0.03-0.64). A comparable trend was observed for onset of testicular enlargement >3ml but did not reach significance...... and Measures: 668 healthy boys (cross-sectional) aged 6.1-21.9 years (COPENHAGEN puberty study conducted from 2005 to 2006) were included. 65 of the boys where followed longitudinally every 6 months. Participants were genotyped for UGT2B17 copy number variation (CNV). Clinical pubertal staging including...... orchidometry, anthropometry and serum reproductive hormone levels. RESULTS: 59 of the 668 boys (8.8%) presented with a homozygous deletion of UGT2B17 (del/del). These boys experienced pubarche at a mean age of 12.73 years (12.00-13.46) vs. 12.40 years (12.11-12.68) in boys heterozygous for deletion of UGT2B17...

Fluency aspects of oral narrative task in del22q11.2 syndrome.

Science.gov (United States)

Santos, Amanda Oliveira; Rossi, Natalia Freitas; Tandel, Maria da Conceição Faria Freitas; Richieri-Costa, Antonio; Giacheti, Célia Maria

2016-01-01

To investigate the fluency aspects of the oral narrative task in individuals with del22q11.2 syndrome and compare them with those of individuals with typical language development. Fifteen individuals diagnosed with del22q11.2 syndrome, both genders, aged 7-17 years participated in this study. They were compared with 15 individuals with typical language development, with similar gender and chronological age profiles. The oral narrative was elicited using the book "Frog, Where Are You?", and the fluency aspects were analyzed according to speech rate and type and frequency of disfluency (typical and stuttering). The number and duration of pauses were also investigated. The data were statistically analyzed. The group with del22q11.2 syndrome showed a higher average when compared with the group without the syndrome for the percentage of typical disfluencies, mainly hesitation and revision. The group presenting the syndrome also showed a higher average for stuttering disfluencies, with pause as the most frequent disfluency. With respect to speech rate, the group with the syndrome presented a lower average for the number of words and syllables per minute. Individuals with del22q11.2 syndrome showed greater difficulties of narration than their peers. The fluency aspects of the oral narrative task in subjects with del22q11.2 syndrome were similar to those of individuals with typical language development regarding the presence of hesitation, revision, and pause, but they were different with respect to frequency of disfluency, which was higher in individuals with the syndrome.

CATALIZADOR ESTRUCTURADO DE Pt/Al2O3 SOBRE UNA ESPUMA DE ACERO INOXIDABLE (AISI 314 PARA LA OXIDACIÓN DE CO

Directory of Open Access Journals (Sweden)

Juan P. Bortolozzi

2011-01-01

Full Text Available Se obtuvo un catalizador estructurado por recubrimiento de Pt/Al2O3 sobre las paredes de una espuma de acero inoxidable AISI 314. Para estabilizar térmicamente e incrementar la rugosidad de la superficie de la espuma original se realizó un tratamiento a 900°C por 2 h. El soporte, Al2O3, y el metal activo, Pt, se incorporaron por inmersión. Las técnicas de caracterización aplicadas, XRD, LRS y SEM-EDX, permiten concluir que el tratamiento térmico previo indujo la formación de óxido de cromo y de las espinelas Mn1+xCr2-xO4-x y FeCr2O4 como fases principales en las paredes del sustrato. El espesor de la capa formada es cercano a 1 μm y los cristales producidos tienen forma octaédrica. El cubrimiento de alúmina presentó en general una apariencia homogénea, sin interacción con los óxidos formados durante el tratamiento. El Pt se distribuyó de manera uniforme, resultando un catalizador muy activo para la reacción test elegida: oxidación de monóxido de carbono.

Cloning and characterization of two duplicated interleukin-17A/F2 genes in common carp (Cyprinus carpio L.): Transcripts expression and bioactivity of recombinant IL-17A/F2.

Science.gov (United States)

Li, Hongxia; Yu, Juhua; Li, Jianlin; Tang, Yongkai; Yu, Fan; Zhou, Jie; Yu, Wenjuan

2016-04-01

Interleukin-17 (IL-17) plays an important role in inflammation and host defense in mammals. In this study, we identified two duplicated IL-17A/F2 genes in the common carp (Cyprinus carpio) (ccIL-17A/F2a and ccIL-17A/F2b), putative encoded proteins contain 140 amino acids (aa) with conserved IL-17 family motifs. Expression analysis revealed high constitutive expression of ccIL-17A/F2s in mucosal tissues, including gill, skin and intestine, their expression could be induced by Aeromonas hydrophila, suggesting a potential role in mucosal immunity. Recombinant ccIL-17A/F2a protein (rccIL-17A/F2a) produced in Escherichia coli could induce the expression of proinflammatory cytokines (IL-1β) and the antimicrobial peptides S100A1, S100A10a and S100A10b in the primary kidney in a dose- and time-dependent manner. Above findings suggest that ccIL-17A/F2 plays an important role in both proinflammatory and innate immunity. Two duplicated ccIL-17A/F2s showed different expression level with ccIL-17A/F2a higher than b, comparison of two 5' regulatory regions indicated the length from anticipated promoter to transcriptional start site (TSS) and putative transcription factor binding site (TFBS) were different. Promoter activity of ccIL-17A/F2a was 2.5 times of ccIL-17A/F2b which consistent with expression results of two genes. These suggest mutations in 5'regulatory region contributed to the differentiation of duplicated genes. To our knowledge, this is the first report to analyze 5'regulatory region of piscine IL-17 family genes. Copyright © 2016 Elsevier Ltd. All rights reserved.

17 CFR 270.8b-2 - Definitions.

Science.gov (United States)

2010-04-01

... such document is filed with such exchange. (j) Share. The term “share” means a share of stock in a... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Definitions. 270.8b-2 Section 270.8b-2 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) RULES AND...

Novel routes to 1,2,3,4-tetrahydropyrrolo[1,2-a]pyrazines and 5,6,9,10,11,11a-hexahydro-8H-pyrido[1,2-a]pyrrolo[2,1-c]pyrazines.

Science.gov (United States)

Katritzky, Alan R; Jain, Ritu; Xu, Yong-Jiang; Steel, Peter J

2002-11-15

Condensation reactions of benzotriazole and 2-(pyrrol-1-yl)-1-ethylamine (1) with formaldehyde and glutaric dialdehyde, respectively, afforded intermediates 2 and 6. Subsequent nucleophilic substitutions of the benzotriazole group in 2 and 6 with Grignard reagents, sodium cyanide, and sodium borohydride gave 1,2,3,4-tetrahydropyrrolo[1,2-a]pyrazines 3a-e, 4, 5 and 5,6,9,10,11,11a-hexahydro-8H-pyrido[1,2-a]pyrrolo[2,1-c]pyrazines 7a-c, 8, 9, respectively, in good yields.

Influence de la composition chimique et de la microstructure sur le dégazage de l'hydrogène des aciers inoxydables austénitiques destinés à l'ultravide

CERN Document Server

Reinert, Marie-Pierre

Dans les installations métalliques sous ultravide, l'hydrogène est le principal constituant de l'atmosphère résiduelle. Le flux de dégazage d'une tôle en acier inoxydable austénitique, matériau fréquemment utilisé en technologie du vide, après un étuvage sous vide, est typiquement de quelques 10-12 Torr.1/cm2.s, et est constitué principalement d'hydrogène. Dans le cadre de cette étude, un appareillage de thermodésorption sous ultravide a été conçu et mis au point pour étudier les phénomènes d'adsorption, de diffusion et de piégeage de l'hydrogène résiduel dans les aciers inoxydables austénitiques. Différents aciers ont été étudiés: l'acier 316L (avec trois modes d'élaboration différents), l'acier 316LN et d'autres aciers stabilisés au titane ou au niobium. La microstructure et la couche d'oxyde de ces aciers ont été caractérisées à l'état de réception et pendant les cycles de thermodésorption. Pendant un cycle de thermodésorption, les principales espèces désorbées...

22q11.2 deletion syndrome

Science.gov (United States)

McDonald-McGinn, Donna M.; Sullivan, Kathleen E.; Marino, Bruno; Philip, Nicole; Swillen, Ann; Vorstman, Jacob A. S.; Zackai, Elaine H.; Emanuel, Beverly S.; Vermeesch, Joris R.; Morrow, Bernice E.; Scambler, Peter J.; Bassett, Anne S.

2016-01-01

22q11.2 deletion syndrome (22q11.2DS) is the most common chromosomal microdeletion disorder, estimated to result mainly from de novo non-homologous meiotic recombination events occurring in approximately 1 in every 1,000 fetuses. The first description in the English language of the constellation of findings now known to be due to this chromosomal difference was made in the 1960s in children with DiGeorge syndrome, who presented with the clinical triad of immunodeficiency, hypoparathyroidism and congenital heart disease. The syndrome is now known to have a heterogeneous presentation that includes multiple additional congenital anomalies and later-onset conditions, such as palatal, gastrointestinal and renal abnormalities, autoimmune disease, variable cognitive delays, behavioural phenotypes and psychiatric illness — all far extending the original description of DiGeorge syndrome. Management requires a multidisciplinary approach involving paediatrics, general medicine, surgery, psychiatry, psychology, interventional therapies (physical, occupational, speech, language and behavioural) and genetic counselling. Although common, lack of recognition of the condition and/or lack of familiarity with genetic testing methods, together with the wide variability of clinical presentation, delays diagnosis. Early diagnosis, preferably prenatally or neonatally, could improve outcomes, thus stressing the importance of universal screening. Equally important, 22q11.2DS has become a model for understanding rare and frequent congenital anomalies, medical conditions, psychiatric and developmental disorders, and may provide a platform to better understand these disorders while affording opportunities for translational strategies across the lifespan for both patients with 22q11.2DS and those with these associated features in the general population. PMID:27189754

Synthesis of 2-iodo- and 2-phenyl-[11C]melatonin: potential PET tracers for melatonin binding sites

International Nuclear Information System (INIS)

Chen Jiajun; Fiehn-Schulze, Brita; Firnau, Guenter; Brough, Paul A.; Snieckus, Victor

1998-01-01

Two 11 C-labelled melatonin derivatives, 2-iodo-[ 11 C]melatonin (2-iodo-5-methoxy-N[ 11 C-acetyl]-tryptamine, an agonist) and 2-phenyl-[ 11 C]melatonin (2-phenyl-5-methoxy-N[ 11 C-acetyl]tryptamine, a putative antagonist) were synthesized from [ 11 C]carbon dioxide. The reaction sequence was common to both compounds and consisted of three steps: (i) carbonylation of methyl magnesium bromide with [ 11 C]carbon dioxide, (ii) conversion of the adduct to [ 11 C]acetyl chloride, (iii) acetylation of the amine precursors (2-iodo-5-methoxy-tryptamine or 2-phenyl-5-methoxy-tryptamine) with [ 11 C]acetyl chloride. The precursors were especially prepared. The radiochemical yield was 19% for 2-iodomelatonin and 32% for 2-phenymelatonin, based on [ 11 C]carbon dioxide; the specific activity ranged from 300 to 600 mCi/μmol. Both labelled 2-substituted-melatonins are intended to be used as radiotracers to study melatonin binding sites in man with positron emission tomography

PPARG, KCNJ11, CDKAL1, CDKN2A-CDKN2B, IDE-KIF11-HHEX, IGF2BP2 and SLC30A8 are associated with type 2 diabetes in a Chinese population.

Directory of Open Access Journals (Sweden)

Cheng Hu

2009-10-01

Full Text Available Recent advance in genetic studies added the confirmed susceptible loci for type 2 diabetes to eighteen. In this study, we attempt to analyze the independent and joint effect of variants from these loci on type 2 diabetes and clinical phenotypes related to glucose metabolism.Twenty-one single nucleotide polymorphisms (SNPs from fourteen loci were successfully genotyped in 1,849 subjects with type 2 diabetes and 1,785 subjects with normal glucose regulation. We analyzed the allele and genotype distribution between the cases and controls of these SNPs as well as the joint effects of the susceptible loci on type 2 diabetes risk. The associations between SNPs and type 2 diabetes were examined by logistic regression. The associations between SNPs and quantitative traits were examined by linear regression. The discriminative accuracy of the prediction models was assessed by area under the receiver operating characteristic curves. We confirmed the effects of SNPs from PPARG, KCNJ11, CDKAL1, CDKN2A-CDKN2B, IDE-KIF11-HHEX, IGF2BP2 and SLC30A8 on risk for type 2 diabetes, with odds ratios ranging from 1.114 to 1.406 (P value range from 0.0335 to 1.37E-12. But no significant association was detected between SNPs from WFS1, FTO, JAZF1, TSPAN8-LGR5, THADA, ADAMTS9, NOTCH2-ADAM30 and type 2 diabetes. Analyses on the quantitative traits in the control subjects showed that THADA SNP rs7578597 was association with 2-h insulin during oral glucose tolerance tests (P = 0.0005, empirical P = 0.0090. The joint effect analysis of SNPs from eleven loci showed the individual carrying more risk alleles had a significantly higher risk for type 2 diabetes. And the type 2 diabetes patients with more risk allele tended to have earlier diagnostic ages (P = 0.0006.The current study confirmed the association between PPARG, KCNJ11, CDKAL1, CDKN2A-CDKN2B, IDE-KIF11-HHEX, IGF2BP2 and SLC30A8 and type 2 diabetes. These type 2 diabetes risk loci contributed to the disease additively.

11β-Hydroxysteroid Dehydrogenase 2 in Preeclampsia

Directory of Open Access Journals (Sweden)

Katarzyna Kosicka

2016-01-01

Full Text Available Preeclampsia is a serious medical problem affecting the mother and her child and influences their health not only during the pregnancy, but also many years after. Although preeclampsia is a subject of many research projects, the etiology of the condition remains unclear. One of the hypotheses related to the etiology of preeclampsia is the deficiency in placental 11β-hydroxysteroid dehydrogenase 2 (11β-HSD2, the enzyme which in normal pregnancy protects the fetus from the excess of maternal cortisol. The reduced activity of the enzyme was observed in placentas from pregnancies complicated with preeclampsia. That suggests the overexposure of the developing child to maternal cortisol, which in high levels exerts proapoptotic effects and reduces fetal growth. The fetal growth restriction due to the diminished placental 11β-HSD2 function may be supported by the fact that preeclampsia is often accompanied with fetal hypotrophy. The causes of the reduced function of 11β-HSD2 in placental tissue are still discussed. This paper summarizes the phenomena that may affect the activity of the enzyme at various steps on the way from the gene to the protein.

The effect of surface nanocrystallization on plasma nitriding behaviour of AISI 4140 steel

Energy Technology Data Exchange (ETDEWEB)

Li Yang [Department of Materials Science and Engineering, Dalian Maritime University, Institute of Metals and Technology, 1 Linghai Street, Dalian 116026 (China); Wang Liang, E-mail: wlimt@yahoo.com [Department of Materials Science and Engineering, Dalian Maritime University, Institute of Metals and Technology, 1 Linghai Street, Dalian 116026 (China); Zhang Dandan; Shen Lie [Department of Materials Science and Engineering, Dalian Maritime University, Institute of Metals and Technology, 1 Linghai Street, Dalian 116026 (China)

2010-11-15

A plastic deformation surface layer with nanocrystalline grains was produced on AISI 4140 steel by means of surface mechanical attrition treatment (SMAT). Plasma nitriding of SMAT and un-SMAT AISI 4140 steel was carried out by a low-frequency pulse excited plasma unit. A series of nitriding experiments has been conducted at temperatures ranging from 380 to 500 deg. C for 8 h in an NH{sub 3} gas. The samples were characterized using X-ray diffraction, scanning electron microscopy, optical microscopy and Vickers microhardness tester. The results showed that a much thicker compound layer with higher hardness was obtained for the SMAT samples when compared with un-SMAT samples after nitriding at the low temperature. In particular, plasma nitriding SMAT AISI 4140 steel at 380 deg. C for 8 h can produced a compound layer of 2.5 {mu}m thickness with very high hardness on the surface, which is similar to un-SMAT samples were plasma nitrided at approximately 430 deg. C within the same time.

Residual stress in a M3:2 PM high speed steel; effect of mechanical loading

DEFF Research Database (Denmark)

Højerslev, Christian; Odén, Magnus; Carstensen, Jesper V.

2001-01-01

X-ray lattice strains were investigated in an AISI M3:2 PM high-speed steel in the as heat treated condition and after exposure to alternating mechanical load. The volume changes during heat treatment were monitored with dilatometry. Hardened and tempered AISI M3:2 steel consists of tempered lath...

The influence of plasma nitriding on the fatigue behavior of austenitic stainless steel types AISI 316 and AISI 304

International Nuclear Information System (INIS)

Varavallo, Rogerio; Manfrinato, Marcos Dorigao; Rossino, Luciana Sgarbi; Spinelli, Dirceu; Riofano, Rosamel Melita Munoz

2010-01-01

The plasma nitriding process has been used as an efficient method to optimize the surface properties of steel and alloy in order to increase their wear, fatigue and corrosion resistance. This paper reports on a study of the composition and influence of the nitrided layer on the high-cycle fatigue properties of the AISI 316 and 304 type austenitic stainless steels. Test specimens of AISI 316 and 304 steel were nitrided at 400 deg C for 6 hours under a pressure of 4.5 mbar, using a gas mixture of 80% volume of H 2 and 20% volume of N 2 . The rotary fatigue limit of both nitrided and non-nitrided steels was determined, and the effect of the treatment on the fatigue limit of the two steels was evaluated. The mechanical properties of the materials were evaluated based on tensile tests, and the nitrided layer was characterized by microhardness tests, scanning electron microscopy and X-ray diffraction. The resulting nitride layer showed high hardness and mechanical strength, increasing the fatigue limit of the nitrided material in comparison with the non-nitrided one. The fatigue limit of the 316 steel increased from 400 MPa to 510 MPa in response to nitriding, while that of the 304 steel increased from 380 MPa to 560 MPa. One of the contributing factors of this increase was the introduction of residual compressive stresses during the surface hardening process, which reduce the onset of crack formation underneath the nitride layer. (author)

The effects of induction hardening on wear properties of AISI 4140 steel in dry sliding conditions

International Nuclear Information System (INIS)

Totik, Y.; Sadeler, R.; Altun, H.; Gavgali, M.

2002-01-01

Wear behaviour of induction hardened AISI 4140 steel was evaluated under dry sliding conditions. Specimens were induction hardened at 1000 Hz for 6, 10, 14, 18, 27 s, respectively, in the inductor which was a three-turn coil with a coupling distance of 2.8 mm. Normalised and induction hardened specimens were fully characterised before and after the wear testing using hardness, profilometer, scanning electron microscopy and X-ray diffraction. The wear tests using a pin-on-disc machine showed that the induction hardening treatments improved the wear behaviour of AISI 4140 steel specimens compared to normalised AISI 4140 steel as a result of residual stresses and hardened surfaces. The wear coefficients in normalised specimens are greater than that in the induction hardened samples. The lowest coefficient of the friction was obtained in specimens induction-hardened at 875 deg. C for 27 s

The effects of induction hardening on wear properties of AISI 4140 steel in dry sliding conditions

Energy Technology Data Exchange (ETDEWEB)

Totik, Y.; Sadeler, R.; Altun, H.; Gavgali, M

2002-02-15

Wear behaviour of induction hardened AISI 4140 steel was evaluated under dry sliding conditions. Specimens were induction hardened at 1000 Hz for 6, 10, 14, 18, 27 s, respectively, in the inductor which was a three-turn coil with a coupling distance of 2.8 mm. Normalised and induction hardened specimens were fully characterised before and after the wear testing using hardness, profilometer, scanning electron microscopy and X-ray diffraction. The wear tests using a pin-on-disc machine showed that the induction hardening treatments improved the wear behaviour of AISI 4140 steel specimens compared to normalised AISI 4140 steel as a result of residual stresses and hardened surfaces. The wear coefficients in normalised specimens are greater than that in the induction hardened samples. The lowest coefficient of the friction was obtained in specimens induction-hardened at 875 deg. C for 27 s.

Interleukin 17 enhances bone morphogenetic protein-2-induced ectopic bone formation

NARCIS (Netherlands)

Croes, M.; Kruyt, M. C.; Groen, W. M.; Van Dorenmalen, K. M.A.; Dhert, W. J.A.; Öner, F. C.; Alblas, J.

2018-01-01

Interleukin 17 (IL-17) stimulates the osteogenic differentiation of progenitor cells in vitro through a synergy with bone morphogenetic protein (BMP)-2. This study investigates whether the diverse responses mediated by IL-17 in vivo also lead to enhanced BMP-2-induced bone formation. Since IL-17 is

Evaluación del comportamiento a fatiga de una unión soldada a tope de acero AISI 1015//Evaluation of the fatigue behaviour of a butt welded joint of AISI 1015 steel

Directory of Open Access Journals (Sweden)

Pavel Michel Almaguer‐Zaldivar

2015-01-01

Full Text Available Las uniones soldadas son un componente importante de una estructura, por lo que siempre es necesario conocer la respuesta de las mismas sometidas a cargas cíclicas. El objetivo de este trabajo es obtener la curva S-N de una unión soldada a tope de acero AISI 1015 y electrodo E6013 como material de aporte. Los ensayos a fatiga se realizaron de acuerdo a la norma ASTM en una máquina universal MTS810. Se utilizaron probetas de sección rectangular. El ciclo de carga fueasimétrico a tracción, con un coeficiente de asimetría de 0,1. Se obtuvo que la unión estudiada tiene un límite de resistencia a la fatiga de 178 MPa, a un punto de corte de 2 039 093 ciclos.Palabras claves: unión soldada, fatiga, curva S-N, AISI 1015, electrodo E6013._______________________________________________________________________________AbstractWelded joints are an important component in structures, by this reason is necessary to know the behaviour of these elements under cyclic loads. The objective of this work is to obtain the S-N curve of the butt welded joint of AISI 1015 steel and electrode E6013 as the contribution material. Fatiguetest was realized within the ASTM standard in the MTS810 testing machine. Rectangular cross section specimens was used. Cyclic loads was asymmetric tensile and the asymmetry ratio used was 0,1. In this study was obtained the fatigue limit equal to 178 MPa, at the cut point of 2 039 093 cycles.Key words: welded joint, fatigue, S-N curve, AISI 1015 steel, electrode E6013.

Agrosearch - Vol 17, No 2 (2017)

African Journals Online (AJOL)

Smallholder food crop farmers' participation in Bank of Agriculture (BOA) loan scheme in Ogun State, Nigeria · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. S.O Adeoye, U.B. Ugalahi, 51– 66. http://dx.doi.org/10.4314/agrosh.v17i2.5 ...

Radiosynthesis and ex vivo evaluation of (R)-(-)-2-chloro-N-[1-{sup 11}C-propyl]n-propylnorapomorphine

Energy Technology Data Exchange (ETDEWEB)

Palner, Mikael [Neurobiology Research Unit, Rigshospitalet, University of Copenhagen, DK-2300, Copenhagen (Denmark); Center for Integrated Molecular Brain Imaging, Copenhagen (Denmark)], E-mail: mikael.palner@nru.dk; McCormick, Patrick [PET Centre, Centre for Addiction and Mental Health, M5T 1RB, Toronto, ON (Canada); Gillings, Nic [Center for Integrated Molecular Brain Imaging, Copenhagen (Denmark); PET and Cyclotron Unit, Rigshospitalet, DK-2300, Copenhagen (Denmark); Begtrup, Mikael [Center for Integrated Molecular Brain Imaging, Copenhagen (Denmark); Institute for Medicinal Chemistry, Pharmaceutical Faculty, University of Copenhagen, DK-2300, Copenhagen (Denmark); Wilson, Alan A. [PET Centre, Centre for Addiction and Mental Health, M5T 1RB, Toronto, ON (Canada); Knudsen, Gitte M. [Neurobiology Research Unit, Rigshospitalet, University of Copenhagen, DK-2300, Copenhagen (Denmark); Center for Integrated Molecular Brain Imaging, Copenhagen (Denmark)

2010-01-15

Introduction: Several dopamine D{sub 2} agonist radioligands have been used with positron emission tomography (PET), including [{sup 11}C-]-(-)-MNPA, [{sup 11}C-]-(-)-NPA and [{sup 11}C]-(+)-PHNO. These radioligands are considered particularly powerful for detection of endogenous dopamine release, but they either provide PET brain images with limited contrast or have affinity for both D{sub 2} and D{sub 3} receptors. We here present the carbon-11 radiolabeling and ex vivo evaluation of 2-Cl-(-)-NPA, a novel PET-tracer candidate with high in vitro D{sub 2}/D{sub 3} selectivity. Methods: 2-Cl-[{sup 11}C]-(-)-NPA and [{sup 11}C]-(-)-NPA were synthesized by a two step N-acylation-reduction process using [{sup 11}C]-propionyl chloride. Awake rats were injected with either tracer, via the tail vein. The rats were decapitated at various times, the brains were removed and quickly dissected, and plasma metabolites were measured. Radioligand specificity, and P-glycoprotein involvement in brain uptake, was also assessed. Results: 2-Cl-[{sup 11}C]-(-)-NPA and [{sup 11}C]-(-)-NPA were produced in high specific activity and purity. 2-Cl-[{sup 11}C]-(-)-NPA accumulated slower in the striatum than [{sup 11}C]-(-)-NPA, reaching maximum concentrations after 30 min. The maximal striatal uptake of 2-Cl-[{sup 11}C]-(-)-NPA (standard uptake value 0.72{+-}0.24) was approximately half that of [{sup 11}C]-(-)-NPA (standard uptake value 1.37{+-}0.18). Nonspecific uptake was similar for the two compounds. 2-Cl-[{sup 11}C]-(-)-NPA was metabolized quickly, leaving only 17% of the parent compound in the plasma after 30 min. The specific binding of 2-Cl-[{sup 11}C]-(-)-NPA was completely blocked and inhibition of P-glycoprotein did not alter the brain uptake. Conclusion: Ex vivo experiments showed, despite a favorable D{sub 2}/D{sub 3} selectivity, that 2-Cl-[{sup 11}C]-(-)-NPA is inferior to [{sup 11}C]-(-)-NPA as a PET tracer in rat, because of slower brain uptake and lower specific to

Molecular cloning and functional expression of the Equine K+ channel KV11.1 (Ether à Go-Go-related/KCNH2 gene) and the regulatory subunit KCNE2 from equine myocardium

DEFF Research Database (Denmark)

Pedersen, Philip Juul; Thomsen, Kirsten Brolin; Olander, Emma Rie

2015-01-01

and conventional PCR on mRNA purified from equine myocardial tissue. Equine KV11.1 and KCNE2 cDNA had a high homology to human genes (93 and 88%, respectively). Equine and human KV11.1 and KV11.1/KCNE2 were expressed in Xenopus laevis oocytes and investigated by two-electrode voltage-clamp. Equine KV11.1 currents...... were larger compared to human KV11.1, and the voltage dependence of activation was shifted to more negative values with V1/2 = -14.2±1.1 mV and -17.3±0.7, respectively. The onset of inactivation was slower for equine KV11.1 compared to the human homolog. These differences in kinetics may account...... for the larger amplitude of the equine current. Furthermore, the equine KV11.1 channel was susceptible to pharmacological block with terfenadine. The physiological importance of KV11.1 was investigated in equine right ventricular wedge preparations. Terfenadine prolonged action potential duration and the effect...

B11 NMR in the layered diborides OsB2 and RuB2

Science.gov (United States)

Suh, B. J.; Zong, X.; Singh, Y.; Niazi, A.; Johnston, D. C.

2007-10-01

B11 nuclear magnetic resonance (NMR) measurements have been performed on B11 enriched OsB2 and RuB2 polycrystalline powder samples in an external field of 4.7T and in the temperature range, 4.2KOsB2 and RuB2 , respectively. The experimental results indicate that a p character dominates the conduction electron wave function at the B site with a negligibly small s character in both compounds.

Surface coating and magnetic properties of Sm2Fe17Nx materials

International Nuclear Information System (INIS)

Noguchi, K.; Machida, K.; Nishimura, M.; Adachi, G.

1998-01-01

Surface coating for finely ground Sm 2 Fe 17 N x (x=-3) powders (diameter 2 Fe 17 N x and (Zn,In)/Cu/Sm 2 Fe 17 N x , showed good oxidation-resistivity and thermal stability compared with the samples prepared without the Cu metal pre-coating, Zn/Sm 2 Fe 17 N x . The epoxy resin- or In metal-bonded magnets produced from the above coated powders, Zn/Cu/Sm 2 Fe 17 N x and (Zn,In)/Cu/Sm 2 Fe 17 N x , under warm molding conditions provided a flux loss of around -15% after standing in air at 120 C for 1000 h, but 30-40% for the conventional injection-type resin-bonded magnets prepared from Nd-Fe-B powders. (orig.)

7 CFR 2.11 - New principles and periodic reviews.

Science.gov (United States)

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false New principles and periodic reviews. 2.11 Section 2.11... Agriculture § 2.11 New principles and periodic reviews. In the exercise of authority delegated by the Secretary, the application of new principles of major importance or a departure from principles established...

Inhibition of Serratia marcescens Smj-11 biofilm formation by Alcaligenes faecalis STN17 crude extract

International Nuclear Information System (INIS)

Lutfi, Zainal; Ahmad, Asmat; Usup, Gires

2014-01-01

Serratia marcescens biofilms are formed when they are bound to surfaces in aqueous environments. S. marcescens utilizes N-acylhomoserine lactone (AHL) as its quorum sensing signal molecule. The accumulation of AHL indicates the bacteria to produce matrices to form biofilms. Prodigiosin (2-methyl-3-pentyl-6-methoxyprodigiosin), which causes red pigmentation in the colonies, are also produced when the AHL reaches a certain threshold. The Alcaligenes faecalis STN17 crude extract is believed to inhibit quorum sensing in the S. marcescens Smj-11 and, thus, impedes its biofilm formation ability. A. faecalis STN17 was grown in marine broth, and ethyl acetate extraction was carried out. The crude compound of A. faecalis STN17 was diluted at high concentration (0.2-6.4 mg/mL) and was taken to confirm anti-biofilm activity through the crystal violet method in 96-wells plate. Then, the crude extract underwent purification using simple solvents partitioning test to discern the respective compounds that had the anti-biofilm activity under the crystal violet method. The crystal violet test showed that the crude did have anti-biofilm activity on S. marcescens Smj-11, but did not kill the cells. This finding signifies that the suppression of biofilm formation in S. marcescens by A. faecalis STN17 has a strong correlation. The partitioning test showed that A. faecalis STN17 crude extract has several compounds and only the compound(s) in chloroform showed activities. In conclusion, the crude extract of A. faecalis STN17 has the ability to inhibit S. marcescens Smj-11 biofilm formation

Inhibition of Serratia marcescens Smj-11 biofilm formation by Alcaligenes faecalis STN17 crude extract

Energy Technology Data Exchange (ETDEWEB)

Lutfi, Zainal; Ahmad, Asmat [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor (Malaysia); Usup, Gires [School of Environmental and Natural Resources Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor (Malaysia)

2014-09-03

Serratia marcescens biofilms are formed when they are bound to surfaces in aqueous environments. S. marcescens utilizes N-acylhomoserine lactone (AHL) as its quorum sensing signal molecule. The accumulation of AHL indicates the bacteria to produce matrices to form biofilms. Prodigiosin (2-methyl-3-pentyl-6-methoxyprodigiosin), which causes red pigmentation in the colonies, are also produced when the AHL reaches a certain threshold. The Alcaligenes faecalis STN17 crude extract is believed to inhibit quorum sensing in the S. marcescens Smj-11 and, thus, impedes its biofilm formation ability. A. faecalis STN17 was grown in marine broth, and ethyl acetate extraction was carried out. The crude compound of A. faecalis STN17 was diluted at high concentration (0.2-6.4 mg/mL) and was taken to confirm anti-biofilm activity through the crystal violet method in 96-wells plate. Then, the crude extract underwent purification using simple solvents partitioning test to discern the respective compounds that had the anti-biofilm activity under the crystal violet method. The crystal violet test showed that the crude did have anti-biofilm activity on S. marcescens Smj-11, but did not kill the cells. This finding signifies that the suppression of biofilm formation in S. marcescens by A. faecalis STN17 has a strong correlation. The partitioning test showed that A. faecalis STN17 crude extract has several compounds and only the compound(s) in chloroform showed activities. In conclusion, the crude extract of A. faecalis STN17 has the ability to inhibit S. marcescens Smj-11 biofilm formation.

17 CFR 240.10A-2 - Auditor independence.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Auditor independence. 240.10A... Exchange Act of 1934 Reports Under Section 10a § 240.10A-2 Auditor independence. It shall be unlawful for an auditor not to be independent under § 210.2-01(c)(2)(iii)(B), (c)(4), (c)(6), (c)(7), and § 210.2...

Low-temperature heat capacity of Al(C11H19O2)3

International Nuclear Information System (INIS)

Bespyatov, Michael A.; Chernyaikin, Ivan S.; Naumov, Viktor N.; Stabnikov, Pavel A.; Gelfond, Nikolay V.

2014-01-01

Highlights: • The temperature dependence of heat capacity of Al(C 11 H 19 O 2 ) 3 has been measured. • The experimental data were used to calculate standard thermodynamic functions. • The thermodynamic functions at 298.15 K are presented. - Abstract: The heat capacity of Al(C 11 H 19 O 2 ) 3 was measured by adiabatic-shield calorimetry in the temperature range 6–320 K; no transition or thermal anomalies were found. The thermodynamic functions (entropy, enthalpy, and reduced Gibbs free energy) at 298.15 K have been calculated using the obtained experimental heat capacity data. The obtained standard values are as follows: C° p,m = (882.3 ± 1.3) J mol −1 K −1 , Δ 0 298.15 S° m = J(980 ± 2) mol −1 K −1 , Δ 0 298.15 H° m = (145.1 ± 0.2) kJ mol −1 , Φ° m = (493.4 ± 1.7) J mol −1 K −1

Effect of mechanical activation on jell boronizing treatment of the AISI 4140

International Nuclear Information System (INIS)

Yılmaz, S.O.; Karataş, S.

2013-01-01

The article presents the effect of mechanical activation on the growth kinetics of boride layer of boronized AISI 4140 steel. The samples were boronized by ferroboron + (SiO 2 –Na 2 O) powders for 873–1173 K temperature and 2, 4, 6 and 8 h times, respectively. The morphology and types of borides formed on the surface of AISI 4140 steel substrate were analyzed. Layer growth kinetics were analyzed by measuring the extent of penetration of FeB and Fe 2 B sublayers as function of treatment time and temperature in the range of 873–1173 K. High diffusivity was obtained by creating a large number of defects through mechanical activation in the form of nanometer sized crystalline particles through the repeated fracturing and cold-welding of the powder particles, and a depth of 100 μm was found in the specimen borided by the 2 h MA powders, for 4 h and 1073 K, where 2000–2350 HV were measured. Consequently, the application conditions of boronizing were improved by usage of mechanical activation. The preferred Fe 2 B boride without FeB could be formed in the boride layer under 973 K boronizing temperature by mechanically activated by ferroboron + sodium silicate powder mixture due to the decrease of the activation energy.

Effect of mechanical activation on jell boronizing treatment of the AISI 4140

Energy Technology Data Exchange (ETDEWEB)

Yılmaz, S.O., E-mail: osyilmaz@firat.edu.tr [F.U. Engineering Faculty, Metallurgical and Material Science, 23119 Elazığ (Turkey); Karataş, S. [F.U. Engineering Faculty, Metallurgical and Material Science, 23119 Elazığ (Turkey)

2013-06-15

The article presents the effect of mechanical activation on the growth kinetics of boride layer of boronized AISI 4140 steel. The samples were boronized by ferroboron + (SiO{sub 2}–Na{sub 2}O) powders for 873–1173 K temperature and 2, 4, 6 and 8 h times, respectively. The morphology and types of borides formed on the surface of AISI 4140 steel substrate were analyzed. Layer growth kinetics were analyzed by measuring the extent of penetration of FeB and Fe{sub 2}B sublayers as function of treatment time and temperature in the range of 873–1173 K. High diffusivity was obtained by creating a large number of defects through mechanical activation in the form of nanometer sized crystalline particles through the repeated fracturing and cold-welding of the powder particles, and a depth of 100 μm was found in the specimen borided by the 2 h MA powders, for 4 h and 1073 K, where 2000–2350 HV were measured. Consequently, the application conditions of boronizing were improved by usage of mechanical activation. The preferred Fe{sub 2}B boride without FeB could be formed in the boride layer under 973 K boronizing temperature by mechanically activated by ferroboron + sodium silicate powder mixture due to the decrease of the activation energy.

Effect of helium on creep and fatigue (MAT 11)

International Nuclear Information System (INIS)

Schroeder, H.

1991-03-01

This final report contains experimental results on mechanical properties (creep, fatigue, tensile) and microstructural investigations (SEM, TEM) of pre-implanted samples of steels or alloys. (AISI 316, AISI 316L, DIN 1.4970, JPCA 8206, DIN 1.4914; Incoloy 800H, Hastelloy X, DIN 1.4981, (Fe 0.49 Ni 0.51 ) 3 V, Fe17Ni17Cr, Fe15Ni15Cr, Nimonic PE 16, Ni8Si). Furthermore theoretical aspects and developed models and mechanisms for helium embrittlement are described. This report is presented in the form of an extended summary without figures. (MM)

Changes of serum IL-2, IL-4, IL-10 and IFN-γ levels after treatment with 131I-17-allylamino-17-demethoxygeldanamycin in VX2 rabbit models

International Nuclear Information System (INIS)

Gao Wen; Liu Lu; Zhou Yun

2007-01-01

Objective: To study the influence of 131 I-17-allylamino-17-demethoxygeldanamycin( 131 I-17-AAG) therapy on immune function in VX2 rabbit models with transplanted liver cancer. Methods: Serum IL-2, IL-4, IL-10 and IFN-γ levels were measured with RIA in 8 VX2 rabbit models with transplanted liver cancer 1-2 weeks after 10mCi 131 I-17-AAG treatment as well as in 8 controls rabbits (models with tumor but without treatment). Results: 1 week after 10mCi 131 I treatment, the serum IL - 2 and IFN-γ levels were significantly lower in the treated rabbits than those in controls (P 0.05). Serum IL-4 and IL-10 levels in the treated rabbits (both at 1 and 2 week) were not significantly different from those in controls (P>0.05). Conclusion: 131 I-17-AAG treatment had transient effects on cellular immunity with no influence on humoral immunity. As a whole, it is a safe to treat VX2 rabbit models with this preparation. (authors)

Spin reorientation and magnetic anisotropy in Y2Co17-xCr x (x 1.17-3.0) compounds

International Nuclear Information System (INIS)

Fuquan, B.; Tegus, O.; Dagula, W.; Brueck, E.; Boer, F.R. de; Buschow, K.H.J.

2005-01-01

Spin reorientation transitions and magnetic anisotropy in Y 2 Co 17-x Cr x (x = 1.17-3.0) compounds have been investigated by means of X-ray diffraction and magnetization measurements. The powder X-ray diffraction patterns show that most samples crystallize as a single phase with the rhombohedral Th 2 Zn 17 -type structure. However, in the compound Y 2 Co 14 Cr 3 the Th 2 Zn 17 phase coexist with the hexagonal Th 2 Ni 17 -type phase. The lattice parameters a and c hardly change and the unit cell volume V increases slightly with increasing Cr content. The X-ray diffraction patterns of the aligned powder of the samples have confirmed that at room temperature the compound with x = 1.17 has planar anisotropy, but the compounds with x = 1.76, 2.34 and 3.00 have uniaxial anisotropy. Spin reorientation phenomena occur in all of the compounds. With increasing Cr content, the Curie temperature, the spin reorientation temperature, the spontaneous magnetization, and the anisotropy constant K 2 of the Y 2 Co 17-x Cr x (x = 1.17-3.0) compounds decrease strongly while the anisotropy constant K 1 increases in the range of x from 1.17 to 2.34 and then decreases in the range of x from 2.34 to 3.00

2-Bromobeclometasone dipropionate

Directory of Open Access Journals (Sweden)

Kamal Aziz Ketuly

2009-08-01

Full Text Available In the crystal structure of 2-bromobeclometasone dipropionate [systematic name: (8S,9R,10S,11S,13S,14S,16S,17R-2-bromo-9α-chloro-11-hydroxy-10,13,16-trimethyl-3-oxo-17-[2-(propionyloxyacetyl]-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthren-17-yl propionate], C28H36BrClO7, the six-membered ring with the 1,4-diene-3-one composition is planar (r.m.s. deviations = 0.03 and 0.04 Å for the two independent molecules, whereas the remaining six-membered rings have chair conformations. Each of the independent molecules self-associates via O—H...Opropionate hydrogen bonding, generating a supramolecular chain running along the b axis. The crystal is twinned, with the monoclinic unit cell emulating an orthorhomic crystal system; the major twin component constitutes approximately 60%.

Microstructure and Mechanical Properties of Laser Clad and Post-cladding Tempered AISI H13 Tool Steel

Science.gov (United States)

Telasang, Gururaj; Dutta Majumdar, Jyotsna; Wasekar, Nitin; Padmanabham, G.; Manna, Indranil

2015-05-01

This study reports a detailed investigation of the microstructure and mechanical properties (wear resistance and tensile strength) of hardened and tempered AISI H13 tool steel substrate following laser cladding with AISI H13 tool steel powder in as-clad and after post-cladding conventional bulk isothermal tempering [at 823 K (550 °C) for 2 hours] heat treatment. Laser cladding was carried out on AISI H13 tool steel substrate using a 6 kW continuous wave diode laser coupled with fiber delivering an energy density of 133 J/mm2 and equipped with a co-axial powder feeding nozzle capable of feeding powder at the rate of 13.3 × 10-3 g/mm2. Laser clad zone comprises martensite, retained austenite, and carbides, and measures an average hardness of 600 to 650 VHN. Subsequent isothermal tempering converted the microstructure into one with tempered martensite and uniform dispersion of carbides with a hardness of 550 to 650 VHN. Interestingly, laser cladding introduced residual compressive stress of 670 ± 15 MPa, which reduces to 580 ± 20 MPa following isothermal tempering. Micro-tensile testing with specimens machined from the clad zone across or transverse to cladding direction showed high strength but failure in brittle mode. On the other hand, similar testing with samples sectioned from the clad zone parallel or longitudinal to the direction of laser cladding prior to and after post-cladding tempering recorded lower strength but ductile failure with 4.7 and 8 pct elongation, respectively. Wear resistance of the laser surface clad and post-cladding tempered samples (evaluated by fretting wear testing) registered superior performance as compared to that of conventional hardened and tempered AISI H13 tool steel.

Magnetic anisotropy of (Sm, Y)2Fe17Ny compounds

International Nuclear Information System (INIS)

Lu, Y.; Tegus, O.; Li, Q.A.; Tang, N.; Yu, M.J.; Zhao, R.W.; Kuang, J.P.; Yang, F.M.; Zhou, G.F.; Li, X.; Boer, F.R. de

1992-01-01

A study of the crystal structure and the magnetic properties, especially the magnetocrystalline anisotropy of (Sm 1-x Y x ) 2 Fe 17 N y compounds (x = 0, 0.2, 0.4, 0.6, 0.8, and 1.0, 2 2 Zn 17 - or Th 2 Ni 17 -type structure as the original compounds. The Curie temperatures decrease from 750 to 700 K as x increases from 0 to 1. The anisotropy field decreases linearly with increasing yttrium content. The spin reorientation has been investigated by means of high field magnetization measurements, AC-susceptibility measurements and thermomagnetic analysis, combined with X-ray diffraction. The anisotropy constants K 1 , K 2 and K 3 were derived by a phenomenological analysis, using magnetization curves measured in high fields, applied perpendicular to the alignment direction of the powder samples. A tentative spin phase diagram of the series is presented. (orig.)

Modeling and Investigation of the Wear Resistance of Salt Bath Nitrided Aisi 4140 via ANN

Science.gov (United States)

Ekinci, Şerafettin; Akdemir, Ahmet; Kahramanli, Humar

2013-05-01

Nitriding is usually used to improve the surface properties of steel materials. In this way, the wear resistance of steels is improved. We conducted a series of studies in order to investigate the microstructural, mechanical and tribological properties of salt bath nitrided AISI 4140 steel. The present study has two parts. For the first phase, the tribological behavior of the AISI 4140 steel which was nitrided in sulfinuz salt bath (SBN) was compared to the behavior of the same steel which was untreated. After surface characterization using metallography, microhardness and sliding wear tests were performed on a block-on-cylinder machine in which carbonized AISI 52100 steel discs were used as the counter face. For the examined AISI 4140 steel samples with and without surface treatment, the evolution of both the friction coefficient and of the wear behavior were determined under various loads, at different sliding velocities and a total sliding distance of 1000 m. The test results showed that wear resistance increased with the nitriding process, friction coefficient decreased due to the sulfur in salt bath and friction coefficient depended systematically on surface hardness. For the second part of this study, four artificial neural network (ANN) models were designed to predict the weight loss and friction coefficient of the nitrided and unnitrided AISI 4140 steel. Load, velocity and sliding distance were used as input. Back-propagation algorithm was chosen for training the ANN. Statistical measurements of R2, MAE and RMSE were employed to evaluate the success of the systems. The results showed that all the systems produced successful results.

Caracterización mediante HRTEM de un acero AISI4140 nitrurado por postdescarga micro-ondas

Directory of Open Access Journals (Sweden)

Béjar-Gómez, L.

2005-12-01

Full Text Available An analysis of the nitrides formed in an AISI 4140 steel nitrided by postdischarge microwave nitriding treatment was carried out by high resolution transmission electron microscopy (HRTEM, fast Fourier transform (FFT and nanoanalysis. The steel samples were nitrided below of the eutectoid transformation point (590 °C, after nitriding the samples were cooling slowly inside in the reactor whit an argon atmosphere. The analysis were carried out in a FEG-TEM PHILIPS TECNAI F20 at 200 Kv. The results showed the morphology and size of the nitrides ε-Fe_2-3N and γ’-Fe₄N, which had coherency whit the matrix. By other hand the following crystallographic relations were determined: (110 Fe-α ║ (1001 ε-Fe_2-3N ║ (110 γ’-Fe₄N and [1-1 0]Fe-α ║ [1 0-1 0] ε-Fe_2-3N ║ [0 1 1] Fe₄N.

Un análisis de las fases de nitruros formados en un acero AISI 4140, nitrurado mediante condiciones de postdescarga micro-ondas, se llevó a cabo por microscopía electrónica de transmisión de alta resolución (HRTEM, rápida transformada de Fourier (FFT y nanoanálisis. Las muestras de acero fueron nitruradas por debajo del punto de transformación eutectoide (590 °C; después del tratamiento de nitruración las piezas fueron enfriadas lentamente dentro del reactor con una atmósfera de argón. Los análisis se realizaron en un microscopio Philips con cañón de emisión de campo Tecnai F20 a 200 Kv (PHILIPS FEG-TEM TECNAI F20. Los resultados mostraron la morfología y tamaño de los nitruros de hierro ε-Fe_2-3N y γ’-Fe₄N, los cuáles mostraron coherencia con la matriz. Además, se obtuvo la siguiente relación de coherencia entre precipitados y matriz: (110 Fe-α ║ (1001 ε-Fe_2-3N ║ (110 γ’-Fe₄N y [1-1 0]Fe-α ║ [1 0-1 0] ε-Fe_2-3N ║ [0 1 1] Fe₄N.

Kondo Effect of U Impurities in Dilute (YU)2Zn17

Science.gov (United States)

Takagi, Shigeru; Suzuki, Hiroyuki; Anzai, Kousuke

2001-10-01

Extending previous work on single-site properties of U ions in (LaU)2Zn17, we have investigated, from ρ(T), χ(T) and Cp(T) on single crystals, (Y1-xUx)2Zn17 with x=0.025 and 0.050, which has almost the same unit-cell volume as an antiferromagnetic heavy-electron compound U2Zn17. Remarkable features in the dilute-impurity limit have been clarified, which include Kondo behavior of ρ(T), large and almost isotropic χimp(T), and strongly enhanced Cimp(T)/T with gigantic γimp=2.02 2.05 J/K2·mole-U as T→0 due to a low characteristic energy-scale of the system. It is shown that gross features of the data are explained in terms of the conventional Kondo effect in the presence of the crystal field with the U3+ \\varGamma6 doublet ground state. It is also shown that the variation of γ with the unit-cell volume in related systems is not explained as a volume effect on TK and that even the behavior of fictitious “paramagnetic” U2Zn17 is not described as a collection of U impurities in dilute (YU)2Zn17.

Microstructural interpretation of the fluence and temperature dependence of the mechanical properties of irradiated AISI 316

International Nuclear Information System (INIS)

Johnson, G.D.; Garner, F.A.; Brager, H.R.; Fish, R.L.

1980-01-01

The effects of neutron irradiation on the mechanical properties of annealed and 20% cold-worked AISI 316 irradiated in EBR-II were determined for the temperature regime of 370 to 760 0 C for fluences up to 8.4 x 10 22 n/cm 2 (E > 0.1 MeV). At irradiation temperatures below about 500 0 C, both annealed and cold-worked material exhibit a substantial increase in the flow stress with increasing fluence. Furthermore, both materials eventually exhibit the same flow stress, which is independent of fluence. At temperatures in the range of 538 to 650 0 C, the cold-worked material exhibits a softening with increasing fluence. Annealed AISI 316 in this temperature regime exhibits hardening and at a fluence of 2 to 3 x 10 22 n/cm 2 (E > 0.1 MeV) reaches the same value of flow stress as the cold-worked material

Oracle JDeveloper 11gR2 Cookbook

CERN Document Server

Haralabidis, Nick

2012-01-01

"Oracle JDeveloper 11gR2 Cookbook" is a practical cookbook which goes beyond the basics with immediately applicable recipes for building ADF applications at an intermediate-to-advanced level. If you are a JavaEE developer who wants to go beyond the basics of building ADF applications with Oracle JDeveloper 11gR2 and get hands on with practical recipes, this book is for you. You should be comfortable with general Java development principles, the JDeveloper IDE, and ADF basics

A novel approach for a C-11C bond formation: synthesis of 17α-([11C]prop-1-ynyl)-3-methoxy-3,17β-estradiol

International Nuclear Information System (INIS)

Wuest, F.; Zessin, J.

2002-01-01

A novel method for a 11 C-C bond formation was developed, employing a cross-coupling reaction between a terminal acetylene and [ 11 C]methyl iodide. The method was used for the synthesis of 17α-([ 11 C]prop-1-ynyl)-3-methoxy-3,17β-estadiol. (orig.)

3D Modelling of Flash Formation in Linear Friction Welded 30CrNiMo8 Steel Chain

Directory of Open Access Journals (Sweden)

Pedro Effertz

2017-10-01

Full Text Available Linear friction welding (LFW is a solid-state welding process that has been thoroughly investigated for chain welding in recent years in order to replace the currently in use Flash Butt Welding (FBW process. Modelling has proven to be an indispensable tool in LFW, thus providing necessary insight to the process, regardless of its final application. This article describes a 3D model developed in the commercial software DEFORM to study the LFW process of 30CrNiMo8 high strength steel in the Hero chain. Hence, a weakly coupled thermal and mechanical model were used, by means of the process experimental input such as displacement histories. The flash morphology and intervening mechanisms were analyzed. A thermal evaluation of different regions in the studied geometry was considered, and a correlation of the modeled and experimental width of the extrusion zone was established.

Effect of various heat treatments on microstructure and mechanical properties of 34CrNiMo6 steel

International Nuclear Information System (INIS)

Abd El-Azim, M.E.; Ghoneim, M.M.; Nasreldin, A.M.; Soliman, S.

1997-01-01

Three different austenitization treatments were applied to high strength 34CrNiMo6 steel: conventional austenitization (CAT), high temperature austenitization (HTA) and duplex treatment (DT). It was found that DT structure has finer prior austenite grain size (30 μm) than those of HTA (200 μm) and CAT (70 μm) structures. DT and HTA structures have coarser lath size for martensite than CAT structure. DT results in higher room temperature impact toughness than HTA and CAT structures and shifts the ductile-brittle transition to lower temperatures by 14 K and 32 K in comparison with HTA and CAT structures, respectively. However, DT structure has intermediate values of room temperature yield stress and ultimate tensile strength between those of CAT and HTA structures. When this steel was tempered at 300 and 400 C it underwent tempered martensite embrittlement associated with intergranular fracture. (orig.)

Positive response to neoadjuvant cyclophosphamide and doxorubicin in topoisomerase II nonamplified/HER2/neu negative/polysomy 17 absent breast cancer patients

Directory of Open Access Journals (Sweden)

Henry G Kaplan

2010-08-01

Full Text Available Henry G Kaplan1, Judith A Malmgren2,3, Mary Atwood1, Lynn C Goldstein41Swedish Cancer Institute at Swedish Medical Center, Seattle, Washington, USA; 2HealthStat Consulting Inc., Seattle, Washington, USA; 3School of Public Health and Community Medicine, Department of Epidemiology, University of Washington, Seattle, Washington, USA; 4PhenoPath Laboratories, Seattle, Washington, USAPurpose: Human epidermal growth factor receptor 2 (HER2/neu, topoisomerase II alpha (TOP2A, and polysomy 17 may predict tumor responsiveness to doxorubicin (DOX therapy.Methods: We identified neoadjuvant DOX/cyclophosphamide treated breast cancer patients in our registry from 1997 to 2008 with sufficient tissue for testing (n = 34. Fluorescence in situ hybridization (FISH testing was done on deparaffinized tissue sections pretreated using vendor’s standard protocol modification, and incubated with US Food and Drug Administration approved Abbott Diagnostics Vysis PathVysion™ probe set, including Spectrum-Green-conjugated probe to a-satellite DNA located at the centromere of chromosome 17 (17p11.1–q11.1 and a Spectrum-Orange-conjugated probe to the TOP2A gene. Morphometric analysis was performed using a MetaSystems image analysis system. Manual counting was performed on all samples in which autofluorescence and/or artifact prevented the counting of sufficient numbers of cells. A ratio >2.0 was considered positive for TOP2A amplification. Polysomy 17 (PS17 presence was defined as signals of ≥2.5. Outcomes were pathological complete response (pCR, partial response (PR, and nonresponse (NR.Results: Of 34 patients tested, one was TOP2A amplified (hormone receptor negative/HER2 ­negative, partial responder. The subset of TOP2A nonamplified, HER2 negative, and PS17 absent (n = 23 patients had treatment response: pCR = 2 (9%, PR = 14 (61%, and NR = 7 (30%. Including the two PS17 present and HER2-positive patients (n = 33, 76% of TOP2A nonamplified patients had pCR or PR

11 CFR 110.11 - Communications; advertising; disclaimers (2 U.S.C 441d).

Science.gov (United States)

2010-01-01

... 11 Federal Elections 1 2010-01-01 2010-01-01 false Communications; advertising; disclaimers (2 U.S... AND EXPENDITURE LIMITATIONS AND PROHIBITIONS § 110.11 Communications; advertising; disclaimers (2 U.S... through radio or television, or through any broadcast, cable, or satellite transmission, must comply with...

Some mechanical properties of borided AISI H13 and 304 steels

International Nuclear Information System (INIS)

Taktak, Sukru

2007-01-01

In the present study, mechanical properties of borides formed on AISI H13 hot work tool and AISI 304 stainless steels have been investigated. Both steels have high chromium content and have a widespread use in the engineering application. Boriding treatment was carried out in slurry salt bath consisting of borax, boric acid, and ferrosilicon at temperature range of 800-950 deg. C for 3, 5, and 7 h. X-ray diffraction analysis of boride layers on the surface of steels revealed various peaks of FeB, Fe 2 B, CrB, and Ni 3 B. Metallographic studies showed that the boride layer has a flat and smooth morphology in the 304 steel while H13 steel was a ragged morphology. The characterization of the boride layer is also carried out by means of the micro-hardness, surface roughness, adhesion, and fracture toughness studies

Partial substitution of vanadium by niobium in AISI H13 steel

International Nuclear Information System (INIS)

Itman Filho, A.; Balancin, O.

1987-01-01

The aim of this work was to study the tempering resistence in conditions of use of the AISI H13 steel, after partial substitution of vanadium by niobium. Four alloys of this steel were elaborated and in three of them the niobim was added in the contents of 0,2; 0,5 and 1,0%. Metallographic techniques were performed to compare qualitatively the niobium effect in several processing and thermal analisys of the steels. Grain size measurements were made after austenitization of the steels, hardness measurements in prepared samples were made after quenching and tempering, tensile testing at elevated temperature was investigated and yield strength, reduction of area after steel breaking and elongation were calculated. After these studies it was possible to certify that the partial substitution of vanadium by niobium did not alter significantly the basic mechanical properties of the AISI H13. (Author) [pt

redox reactions of uranium in the presence of potassium 2-phospho-17-tungstate

International Nuclear Information System (INIS)

Maslov, L.P.; Rykov, A.G.; Sirotinkina, L.V.

1986-01-01

The redox reactions of uranium in the presence of potassium 2-phospho-17-tungstate (17W2P) - K 10 P 2 W 17 O 61 - were studied by the methods of spectrophotometry and potentiometry. It was established that in the presence of 17W2P the UO /SUP 2/2/ + ion is reduced by iron(II) to uranium(IV) as a result of the binding of U(IV) into a strong complex with composition (U(p 2 W 17 O 61 ) 2 ) 16- . The peculiarities of the coordination of uranium(IV) by voluminous 17W2P ligands are the cause of the different nature of its interaction with various types of oxidizing agents. It was established that under the action of oxidizing agents (K 2 Cr 2 O 7 , KMnO 4 ), the reduced form of which is a complex with 17W2P, there is a conversion of the complex of uranium(IV) to the corresponding complex of uranium(V), evidently with conservation of a structure analogous to that for uranium(IV). It was also shown that uranium(IV) in complex with 17W2P is practically not oxidized in the cold by persulfate ions which react according to a radical mechanism, whereas weaker oxidizing agents, for example, H 2 O 2 , oxidize it to the UO /SUP 2/2/ + ion. Hypotheses are advanced on the possible mechanisms of the occurrence of the corresponding reactions

18 CFR 2.17 - Price discrimination and anticompetitive effect (price squeeze issue).

Science.gov (United States)

2010-04-01

... INTERPRETATIONS Statements of General Policy and Interpretations Under the Federal Power Act § 2.17 Price... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Price discrimination and anticompetitive effect (price squeeze issue). 2.17 Section 2.17 Conservation of Power and Water...

2,2′-[1,1′-(Heptane-1,7-diyldioxydinitrilodiethylidyne]di-1-naphthol

Directory of Open Access Journals (Sweden)

Wen-Kui Dong

2009-07-01

Full Text Available The molecule of the title compound, C31H34N2O4, adopts an L-shaped configuration, in which the naphthalene units are approximately perpendicular, making a dihedral angle of 87.89 (3°. Intramolecular H-bonds are formed between the OH substituents and the N atoms at each end of the molecule. In the crystal structure, each molecule links six other molecules into an infinite three-dimensional network supramolecular structure, which is built from one-dimensional zigzag chains via weak C—H...π stacking and intermolecular C—H...O hydrogen bonds.

(-)-N-[11C]propyl-norapomorphine: a positron-labeled dopamine agonist for PET imaging of D2 receptors

International Nuclear Information System (INIS)

Hwang, Dah-Ren; Kegeles, Lawrence S.; Laruelle, Marc

2000-01-01

Imaging neuroreceptors with radiolabeled agonists might provide valuable information on the in vivo agonist affinity states of receptors of interest. We report here the radiosynthesis, biodistribution in rodents, and imaging studies in baboons of [ 11 C]-labeled (-)-N-propyl-norapomorphine [(-)-NPA]. (-)-[ 11 C]NPA was prepared by reacting norapomorphine with [ 11 C]propionyl chloride and a lithium aluminum hydride reduction. [ 11 C]Propionyl chloride was prepared by reacting [ 11 C]CO 2 with ethylmagnesium bromide, followed by reacting with phthaloyl chloride. The radiochemical yield of (-)-[ 11 C]NPA was 2.5% at end of synthesis (EOS), and the synthesis time was 60 min. The specific activity was 1700±1900 mCi/μmol ( N=7; ranged 110-5200 mCi/μmol at EOS). Rodent biodistribution studies showed high uptake of [ 11 C](-)-NPA in D 2 receptor-rich areas, and the striatum/cerebellum ratios were 1.7, 3.4, and 4.4 at 5 min, 30 min, and 60 min postinjection, respectively. Pretreating the animals with haloperidol (1 mg/kg) decreased the striatum/cerebellum ratio at 30 min postinjection to 1.3. (-)-[ 11 C]NPA was also evaluated via baboon positron emission tomography (PET) studies. Under control conditions ( N=4), rapid uptake of the tracer was observed and the striatum/cerebellum ratio reached 2.86±0.15 at 45 min postinjection. Following haloperidol pretreatment (0.2 mg/kg IV), the striatum/cerebellum ratio was 1.29 at 45 min postinjection. The result demonstrated the existence of specific binding of this new tracer to the D 2 receptor. To our knowledge, the current finding of a striatum/cerebellum ratio of 2.8 in baboon was the highest reported with a radiolabeled D 2 agonist. (-)-[ 11 C]NPA is a promising new D 2 agonist PET tracer for probing D 2 receptors in vivo using PET

(-)-N-[(11)C]propyl-norapomorphine: a positron-labeled dopamine agonist for PET imaging of D(2) receptors.

Science.gov (United States)

Hwang, D R; Kegeles, L S; Laruelle, M

2000-08-01

Imaging neuroreceptors with radiolabeled agonists might provide valuable information on the in vivo agonist affinity states of receptors of interest. We report here the radiosynthesis, biodistribution in rodents, and imaging studies in baboons of [(11)C]-labeled (-)-N-propyl-norapomorphine [(-)-NPA]. (-)-[(11)C]NPA was prepared by reacting norapomorphine with [(11)C]propionyl chloride and a lithium aluminum hydride reduction. [(11)C]Propionyl chloride was prepared by reacting [(11)C]CO(2) with ethylmagnesium bromide, followed by reacting with phthaloyl chloride. The radiochemical yield of (-)-[(11)C]NPA was 2.5% at end of synthesis (EOS), and the synthesis time was 60 min. The specific activity was 1700+/-1900 mCi/micromol ( N=7; ranged 110-5200 mCi/micromol at EOS). Rodent biodistribution studies showed high uptake of [(11)C](-)-NPA in D(2) receptor-rich areas, and the striatum/cerebellum ratios were 1.7, 3.4, and 4.4 at 5 min, 30 min, and 60 min postinjection, respectively. Pretreating the animals with haloperidol (1 mg/kg) decreased the striatum/cerebellum ratio at 30 min postinjection to 1.3. (-)-[(11)C]NPA was also evaluated via baboon positron emission tomography (PET) studies. Under control conditions ( N=4), rapid uptake of the tracer was observed and the striatum/cerebellum ratio reached 2.86+/-0.15 at 45 min postinjection. Following haloperidol pretreatment (0.2 mg/kg IV), the striatum/cerebellum ratio was 1.29 at 45 min postinjection. The result demonstrated the existence of specific binding of this new tracer to the D(2) receptor. To our knowledge, the current finding of a striatum/cerebellum ratio of 2.8 in baboon was the highest reported with a radiolabeled D(2) agonist. (-)-[(11)C]NPA is a promising new D(2) agonist PET tracer for probing D(2) receptors in vivo using PET.

The threshold photoelectron spectrum of the geminal chloro-fluoro-ethene (1,1-C2H2FCl) isomer. Experiment and theory

International Nuclear Information System (INIS)

Locht, R; Leyh, B; Dehareng, D

2014-01-01

The threshold photoelectron spectrum (TPES) of 1,1-C 2 H 2 FCl has been measured for the first time using synchrotron radiation. It has been compared to the HeI PES obtained earlier (Tornow et al 1990 Chem. Phys. 146 115). Eight photoelectron bands have been observed at 10.22, 12.45, 13.28, 14.29, 14.99, 17.12, 17.67 and at 20.23 eV successively. Only the first three bands exhibit a rich and extensive vibrational structure. Their adiabatic ionization energies are measured and a detailed vibrational analysis is presented. The assignments of the electronic bands and of the vibrational wavenumbers were made by using ab initio quantum chemical calculations. These allowed us to provide the MO description of the eight electronic states in terms of ionization and double excitation. The good correlation between predicted vibrational wavenumbers and the experimental values provides a strong basis for the assignment of all the vibrational structures. (paper)

Swelling behavior of titanium-modified AISI 316 alloys

International Nuclear Information System (INIS)

Garner, F.A.; Brager, H.R.; Puigh, R.J.

1984-01-01

It appears that titanium additions to stainless steels covering a wide compositional range around the specifications of AISI 316 result only in an increased delay period before neutron-induced void swelling proceeds. Once swelling is initiated the post transient behavior of both annealed and cold-worked titanium-modified steels is quite consistent with that of AISI 316, approaching a relatively temperature-independent swelling rate of approx. 1% per dpa

Modelling and analysis of tool wear and surface roughness in hard turning of AISI D2 steel using response surface methodology

Directory of Open Access Journals (Sweden)

M. Junaid Mir

2018-01-01

Full Text Available The present work deals with some machinability studies on tool wear and surface roughness, in finish hard turning of AISI D2 steel using PCBN, Mixed ceramic and coated carbide inserts. The machining experiments are conducted based on the response surface methodology (RSM. Combined effects of three cutting parameters viz., cutting speed, cutting time and tool hardness on the two performance outputs (i.e. VB and Ra, are explored employing the analysis of variance (ANOVA.The relationship(s between input variables and the response parameters are determined using a quadratic regression model. The results show that the tool wear was influenced principally by the cutting time and in the second level by the cutting tool hardness. On the other hand, cutting time was the dominant factor affecting workpiece surface roughness followed by cutting speed. Finally, the multiple response optimizations of tool wear and surface roughness were carried out using the desirability function approach (DFA.

PODAAC-RSX12-L2B11

Data.gov (United States)

National Aeronautics and Space Administration — This dataset contains the RapidScat Level 2B 12.5km Version 1.1 science-quality ocean surface wind vectors. The Level 2B wind vectors are binned on a 12.5 km Wind...

17 CFR 155.2 - Trading standards for floor brokers.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Trading standards for floor brokers. 155.2 Section 155.2 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION TRADING STANDARDS § 155.2 Trading standards for floor brokers. Each contract market shall adopt and submit...

A preliminary PET evaluation of the new dopamine D2 receptor agonist [11C]MNPA in cynomolgus monkey

International Nuclear Information System (INIS)

Finnema, Sjoerd J.; Seneca, Nicholas; Farde, Lars; Shchukin, Evgeny; Sovago, Judit; Gulyas, Balazs; Wikstroem, Hakan V.; Innis, Robert B.; Neumeyer, John L.; Halldin, Christer

2005-01-01

This study describes the preliminary positron emission tomography (PET) evaluation of a dopamine D 2 -like receptor agonist (R)-2- 11 CH 3 O-N-n-propylnorapomorphine ([ 11 C]MNPA), as a potential new radioligand for in vivo imaging of the high-affinity state of the dopamine D 2 receptor (D 2 R). MNPA is a selective D 2 -like receptor agonist with a high affinity (K i =0.17 nM). [ 11 C]MNPA was successfully synthesized by direct O-methylation of (R)-2-hydroxy-NPA using [ 11 C]methyl iodide and was evaluated in cynomolgus monkeys. This study included baseline PET experiments and a pretreatment study using unlabeled raclopride (1 mg/kg). High uptake of radioactivity was seen in regions known to contain high D 2 R, with a maximum striatum-to-cerebellum ratio of 2.23±0.21 at 78 min and a maximum thalamus-to-cerebellum ratio of 1.37±0.06 at 72 min. The pretreatment study demonstrated high specific binding to D 2 R by reducing the striatum-to-cerebellum ratio to 1.26 at 78 min. This preliminary study indicates that the dopamine agonist [ 11 C]MNPA has potential as an agonist radioligand for the D 2 -like receptor and has potential for examination of the high-affinity state of the D 2 R in human subjects and patients with neuropsychiatric disorders

Influence of the surface finishing on electrochemical corrosion characteristics of AISI 316L stainless steel

Czech Academy of Sciences Publication Activity Database

Dundeková, S.; Hadzima, B.; Fintová, Stanislava

2015-01-01

Roč. 22, č. 2 (2015), s. 77-84 ISSN 1335-0803 Institutional support: RVO:68081723 Keywords : AISI 316L stainless steel * EIS * Corrosion Subject RIV: JK - Corrosion ; Surface Treatment of Materials http://ojs.mateng.sk/index.php/Mateng/article/view/167/278

Swelling behavior of manganese-bearing AISI 216 steel

International Nuclear Information System (INIS)

Gelles, D.S.; Garner, F.A.

1984-01-01

The inclusion of 8.5 wt % manganese in AISI 216 does not appear to alter the swelling behavior from that found to be typical of austenitic alloys with comparable levels of other austentite-stabilizing elements. The swelling in AISI 216 in EBR-II is quite insensitive to irradiation temperature in the range 400-650 0 C. Microscopy reveals that this may arise from the low level of precipitation that occurs in the alloy

28 CFR 2.17 - Original jurisdiction cases.

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2010-07-01

... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Original jurisdiction cases. 2.17 Section... Original jurisdiction cases. (a) Following any hearing conducted pursuant to these rules, the Regional Commissioner may designate that a case should be decided as an original jurisdiction case. If the Regional...

10 CFR 960.5-2-11 - Tectonics.

Science.gov (United States)

2010-01-01

... REPOSITORY Preclosure Guidelines Ease and Cost of Siting, Construction, Operation, and Closure § 960.5-2-11... of active faulting within the geologic setting. (2) Historical earthquakes or past man-induced... repository construction, operation, and closure may be larger then predicted from historical seismicity. (d...

Surface characterization and wear behaviour of laser surface melted AISI 316L stainless steel

CSIR Research Space (South Africa)

Kumar, A

2010-01-01

Full Text Available The present study concerns an in depth investigation of the influence of laser surface melting of AISI 316L stainless steel using Ar and N2 as shrouding atmosphere. Laser surface melting has been carried out using a 5 kW continuous wave (CW) fibre...

Rapid labelling of radiopharmaceuticals using 11CO2 and 11CH4

International Nuclear Information System (INIS)

Crouzel, C.

1988-07-01

In the past two decades, much effort has been devoted to the development of new molecules, labelled with β+ emitters usable for Positron Emission Tomography. Gaseous forms of 11 C ( 11 CO 2 or 11 CH 4 ) must be converted to a reactive form known as a ''radioactive precursor'': 11 C-methanol, 11 C-formaldehyde, 11 C-acetone, 11 C-phosgene, 11 C-diazomethane, 11 C-methylamine. These precursors are used to label radiopharmaceuticals. Few examples are given: 11 C-prazosin, 11 C-CGP 12177, 11 C-pindolol. Such synthesis procedures require strong initial activity (1.5 Ci). The processes are therefore remotely controlled or automated, and confined to shielded cells. Small laboratory robots have lately been introduced for this type of production

Corrosion behaviour of AISI 204Cu and AISI 304 stainless steels in simulated pore solution

Energy Technology Data Exchange (ETDEWEB)

Kocijan, Aleksandra [Institute of Metals and Technology, Ljubljana (Slovenia)

2013-10-15

The evolution of the passive films on AISI 204Cu and AISI 304 stainless steels in simulated pore solution for steel reinforcements in concrete, and with and without the addition of chloride, was studied using cyclic voltammetry and potentiodynamic measurements. The passive layers were studied at open-circuit potential by means of X-ray photoelectron spectroscopy. The passive films on both materials predominantly contained Cr-oxides, whereas the Fe-species were markedly depleted. Mn-enrichment was also observed. The addition of chloride ions did not have a significant influence on the composition of the passive layers. The surface morphology of the products formed on the surface of both investigated materials at open-circuit potential and at high over-potentials in the presence of chloride was studied using scanning electron microscopy. (orig.)

The effect of CO{sub 2} laser beam welded AISI 316L austenitic stainless steel on the viability of fibroblast cells, in vitro

Energy Technology Data Exchange (ETDEWEB)

Köse, Ceyhun, E-mail: ceyhun.kose@gop.edu.tr [Faculty of Natural Sciences and Engineering, Department of Mechanical Engineering, Gaziosmanpaşa University, Tokat (Turkey); Kaçar, Ramazan, E-mail: rkacar@karabuk.edu.tr [Faculty of Technology Department of Manufacturing Engineering, Karabuk University, Karabuk 78050 (Turkey); Zorba, Aslı Pınar, E-mail: aslipinarzorba@gmail.com [Graduate School of Natural and Applied Sciences, Department of Bioengineering Cell Culture and Tissue Engineering, Yıldız Technical University, Istanbul (Turkey); Bağırova, Melahat, E-mail: mbagir@yildiz.edu.tr [Department of Bioengineering Cell Culture and Tissue Engineering, Yıldız Technical University, Istanbul (Turkey); Allahverdiyev, Adil M., E-mail: adil@yildiz.edu.tr [Department of Bioengineering Cell Culture and Tissue Engineering, Yıldız Technical University, Istanbul (Turkey)

2016-03-01

It has been determined by the literature research that there is no clinical study on the in vivo and in vitro interaction of the cells with the laser beam welded joints of AISI 316L biomaterial. It is used as a prosthesis and implant material and that has adequate mechanical properties and corrosion resistance characteristics. Therefore, the interaction of the CO{sub 2} laser beam welded samples and samples of the base metal of AISI 316L austenitic stainless steel with L929 fibroblast cells as an element of connective tissue under in vitro conditions has been studied. To study the effect of the base metal and the laser welded test specimens on the viability of the fibroblast cells that act as an element of connective tissues in the body, they were kept in DMEMF-12 medium for 7, 14, 28 days and 18 months. The viability study was experimentally studied using the MTT method for 7, 14, 28 days. In addition, the direct interaction of the fibroblast cells seeded on 6 different plates with the samples was examined with an inverted microscope. The MTT cell viability experiment was repeated on the cells that were in contact with the samples. The statistical relationship was analyzed using a Tukey test for the variance with the GraphPad statistics software. The data regarding metallic ion release were identified with the ICP-MS method after the laser welded and main material samples were kept in cell culture medium for 18 months. The cell viability of the laser welded sample has been detected to be higher than that of the base metal and the control based on 7th day data. However, the laser welded sample's viability of the fibroblast cells has diminished by time during the test period of 14 and 28 days and base metal shows better viability when compared to the laser welded samples. On the other hand, the base metal and the laser welded sample show better cell viability effect when compared to the control group. According to the ICP-MS results of the main material and

Thermal stability of polyoxometalate compound of Keggin K8[2-SiW11O39]∙nH2O supported with SiO2

Directory of Open Access Journals (Sweden)

Yunita Sari M A

2017-06-01

Full Text Available Synthesis through sol-gel method and characterization of polyoxometalate compound of K8[b2-SiW11O39]∙nH2O supported with SiO2 have been done. The functional groups of polyoxometalate compound  was characterized by FT-IR spectrophotometer for the fungtional groups and the degree’s of crystalinity  using XRD. The acidity of K8[b2-SiW11O39]∙nH2O/SiO2 was determined qualitative analysis using ammonia and pyridine adsorption and the quantitative analysis using potentiometric titration method. The results of FT-IR spectrum of K8[b2-SiW11O39]∙nH2O appeared at  wavenumber 987.55 cm-1 (W=O, 864.11 cm-1 (W-Oe-W, 756.1 cm-1 (W-Oc-W, 3425.58 cm-1 (O-H, respectively and spectrum of  K8[b2-SiW11O39]SiO2 appeared at wavenumber  956.69 cm-1 (W=O, 864.11 cm-1 (W-Oe-W, 3448.72 cm-1 (O-H, respectively. The diffraction of XRD pattern of K8[b2-SiW11O39]∙nH2O and K8[b2-SiW11O39]∙nH2O/SiO2 compounds show high crystalinity. The acidic properties showed K8[b2-SiW11O39]∙nH2O/SiO2 more acidic compared to K8[b2-The SiW11O39]∙nH2O. The qualitative analysis showed pyridine compound adsorbed more of polyoxometalate compound of K8[b2-SiW11O39]∙nH2O/SiO2. Analysis of stability showed that the K8[b2-SiW11O39]∙nH2O/SiO2 at temperature 500°C has structural changes compare to 200-400oC which was indicated from vibration at wavenumber 800-1000 cm-1. Keywords : K8[b2-SiW11O39]∙nH2O, polyoxometalate, SiO2.

49 CFR 17.11 - What are the Secretary's obligations in interstate situations?

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2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false What are the Secretary's obligations in interstate situations? 17.11 Section 17.11 Transportation Office of the Secretary of Transportation INTERGOVERNMENTAL REVIEW OF DEPARTMENT OF TRANSPORTATION PROGRAMS AND ACTIVITIES § 17.11 What are the Secretary's...

37 CFR 2.17 - Recognition for representation.

Science.gov (United States)

2010-07-01

..., registrant, or party (e.g., a corporate officer or general partner of a partnership). In the case of joint..., DEPARTMENT OF COMMERCE RULES OF PRACTICE IN TRADEMARK CASES Representation by Attorneys Or Other Authorized Persons § 2.17 Recognition for representation. (a) Authority to practice in trademark cases. Only an...

22q11.2 deletion syndrome: behaviour problems of children and adolescents and parental stress.

Science.gov (United States)

Briegel, W; Schneider, M; Schwab, K Otfried

2008-11-01

22q11.2 deletion syndrome can be associated with a variety of somatic symptoms, developmental delays and psychiatric disorders. At present, there is little information on behaviour problems, parental stress and possible relations between these factors. Therefore, this study investigates behaviour problems of children and adolescents with 22q11.2DS, and their primary caregivers' stress. Parents of 4-17 year old subjects known to the German 22q11.2 deletion syndrome foundation were anonymously asked to fill out several questionnaires, e.g. the Child Behavior Checklist 4-18 (CBCL/4-18). The primary caregivers of 77/126 children [43 males, 34 females, mean age: 8;0 (4;0-16;11) years] sent back filled-out questionnaires. Forty-six of 76 subjects were rated as clinical on at least one of the CBCL-scales. Males had significantly higher scores on the total problems scale and the internalizing problems scale than females. The patients' age correlated with several CBCL-scales. Eleven of 49 subjects were suspicious of an autism spectrum disorder. Compared with the general population, but not with other parents of mentally and/or physically handicapped children, the primary caregivers experienced higher levels of stress, but showed normal life satisfaction. In spite of high rates of clinical behaviour problems among children and adolescents with 22q11.2DS and despite increased parental stress, most primary caregivers seem to have effective coping strategies, e.g. partnership support, to sustain normal levels of life satisfaction.

Thermodynamics of the (Sm{sub 2}Fe{sub 17-x}Ga{sub x}+H{sub 2}) system

Energy Technology Data Exchange (ETDEWEB)

Kubis, M.; Handstein, A.; Gebel, B.; Gutfleisch, O.; Mueller, K.H.; Schultz, L. [Institut fuer Festkoerper- und Werkstofforschung Dresden e.V. (Germany). Inst. fuer Metallische Werkstoffe

2000-08-10

Sm{sub 2}Fe{sub 17-x}Ga{sub x} samples (with x=0, 0.5, 1, and 2) were disproportionated into SmH{sub 2} and {alpha}-(Fe,Ga) by heating the samples in 4 MPa hydrogen up to 650 C. It was possible to disproportionate even the more stable compounds with a higher Ga content under these conditions. The recombination into the original 2:17 phase was carried out by annealing in low hydrogen pressures of 2.5, 12 and 60 kPa. The values of the hydride formation enthalpy, {delta}H, and of the change of entropy, {delta}S, for the Sm{sub 2}Fe{sub 17-x}Ga{sub x} compounds were obtained by using the Van't Hoff relation. It was found that the negative {delta}H increases monotonically from 141 to 229 kJ/mol H{sub 2} and the negative {delta}S increases monotonically from 112 to 258 J/Kmol H{sub 2} for x=0 to x=2, respectively. These results show that the higher stability for the compounds with increasing Ga content is mainly attributed to the increasing negative change of entropy -{delta}S and not, as expected before, to a decrease of -{delta}H. (orig.)

22q11.2 deletion status and disease burden in children and adolescents with tetralogy of Fallot.

Science.gov (United States)

Mercer-Rosa, Laura; Paridon, Stephen M; Fogel, Mark A; Rychik, Jack; Tanel, Ronn E; Zhao, Huaqing; Zhang, Xuemei; Yang, Wei; Shults, Justine; Goldmuntz, Elizabeth

2015-02-01

Patients with repaired tetralogy of Fallot experience variable outcomes for reasons that are incompletely understood. We hypothesize that genetic variants contribute to this variability. We sought to investigate the association of 22q11.2 deletion status with clinical outcome in patients with repaired tetralogy of Fallot. We performed a cross-sectional study of tetralogy of Fallot subjects who were tested for 22q11.2 deletion, and underwent cardiac magnetic resonance, exercise stress test, and review of medical history. We studied 165 subjects (12.3±3.1 years), of which 30 (18%) had 22q11.2 deletion syndrome (22q11.2DS). Overall, by cardiac magnetic resonance the right ventricular ejection fraction was 60±8%, pulmonary regurgitant fraction was 34±17%, and right ventricular end-diastolic volume was 114±39 cc/m(2). On exercise stress test, maximum oxygen consumption was 76±16% predicted. Despite comparable right ventricular function and pulmonary regurgitant fraction, on exercise stress test the 22q11.2DS had significantly lower percent predicted: forced vital capacity (61.5±16 versus 80.5±14; Ptetralogy of Fallot. These findings may provide avenues for intervention to improve outcomes, and should be re-evaluated longitudinally because these associations may become more pronounced with time. © 2015 American Heart Association, Inc.

Synthesis and evaluation of (S)-4-(3-(2'-[C-11]isopropylamino)-2-hydroxy-propoxy)-2H-benzimidazol-2-one ((S)-[C-11]CGP 12388) and (S)-4-(3-((1'-[F-18]-fluoroisopropyl)amino)-2-hydroxypropoxy)-2H-benzimidazol-2-one ((S)-[F-18]Fluoro-CGP 12388) for visualization of beta-adrenoceptors with positron emission tomography

NARCIS (Netherlands)

Elsinga, PH; vanWaarde, A; Jaeggi, KA; Schreiber, G; Heldoorn, M; Vaalburg, W

1997-01-01

The beta-adrenoceptor antagonist (S)-[C-11]CGP 12177 (4-(3-(tert-butylamino)-2-hydroxypropoxy)- 2H-benzimidazol-2[C-11]-one) is a generally accepted radioligand for cardiac and pulmonary PET studies. The synthesis of [C-11]CGP 12177 is a laborious and often troublesome procedure. Therefore, (S)-C GP

Guaifenesin Pharmacokinetics Following Single‐Dose Oral Administration in Children Aged 2 to 17 Years

Science.gov (United States)

Thompson, Gary A.; Solomon, Gail; Albrecht, Helmut H.; Reitberg, Donald P.

2016-01-01

Abstract This study characterized guaifenesin pharmacokinetics in children aged 2 to 17 years (n = 40) who received a single oral dose of guaifenesin (age‐based doses of 100‐400 mg) 2 hours after breakfast. Plasma samples were obtained before and for 8 hours after dosing and analyzed for guaifenesin using liquid chromatography‐tandem mass spectrometry. Pharmacokinetic parameters were estimated using noncompartmental methods, relationships with age were assessed using linear regression, and dose proportionality was assessed on 95% confidence intervals. Based on the upper dose recommended in the monograph (for both children and adolescents), area under the curve from time zero to infinity and maximum plasma concentration both increased with age. However, when comparing the upper dose for children aged 2 to 11 years with the lower dose for adolescents aged 12 to 17 years, similar systemic exposure was observed. As expected due to increasing body size, oral clearance (CLo) and terminal volume of distribution (Vz/F) increased with age. Due to a larger increase in Vz/F than CLo, an increase in terminal exponential half‐life was also observed. Allometric scaling indicated no maturation‐related changes in CLo and Vz/F. PMID:26632082

Interphase Constituent of Laminated Composites Ti46Zr26Cu17Ni11

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XU Bingtong

2017-10-01

Full Text Available Thermal analysis of the Ti46Zr26Cu17Ni11 amorphous ribbon prepared by melt spinning was conducted by using DSC. Accordingly the amorphous alloy was treated by vacuum heat treatment at 693 K (Tg, 753 K (Tg-Tx1 and 813 K (> Tx1 for different time to analyze the crystallization behavior. Taking Ti46Zr26Cu17Ni11 amorphous alloy, TA2 and pure Al as raw materials, laminated composites were fabricated by Gleeble-3500 thermal simulator at 873 K, 10 MPa and 8 h. The phase composition, precipitation order and properties of interface layers were investigated by SEM, TEM, micro hardness tester, combined thermodynamics and element diffusion theory. The results indicate that the glass transition temperature Tg of Ti46Zr26Cu17Ni11 amorphous is 720 K and the initial crystallization temperature Tx1 is 788 K. The I phase is crystallized from the amorphous at first, followed by a ternary or quaternary Laves phase and a TiNi phase precipited. After hot pressing, the interface between pure Al and crystallization layer is divided into two parts, which are Al3Ni with small thickness and Al3(Ti0.6Zr0.4 with fine grain and uniform microstructure. The interfaces are straight and there are no defects, with a thickness ratio of about 6.5:1 compared with interface layer between pure Ti with Al. The hardness of Al3(Ti0.6Zr0.4 and Al3Ti are 564.2HV and 579.8HV respectively. The plasticity of Al3(Ti0.6Zr0.4 layer is better.

Chemopreventive effect of chalcone derivative, L2H17, in colon cancer development

International Nuclear Information System (INIS)

Xu, Shanmei; Chen, Minxiao; Chen, Wenbo; Hui, Junguo; Ji, Jiansong; Hu, Shuping; Zhou, Jianmin; Wang, Yi; Liang, Guang

2015-01-01

Colon cancer is the third most commonly diagnosed cancer and the second leading cause of cancer mortality worldwide. Chalcone and its derivatives are reported to exhibit anti-cancer effects in several cancer cell lines, including colon cancer cells. In addition, chalcones have advantages such as poor interaction with DNA and low risk of mutagenesity. In our previous study, a group of chalcone derivatives were synthesized and exhibited strong anti-inflammatory activities. In this study, we evaluated the anti-cancer effects of the chalcone derivative, L2H17, in colon cancer cells. The cytotoxicities of L2H17 on various colon cancer cell lines were investigated by MTT and clonogenic assay. Cell cycle and apoptosis analysis were performed to evaluate the molecular mechanism of L2H17-mediated inhibition of tumor growth. Also, scratch wound and matrigel invasion experiments were performed to estimate the cell migration and invasion after L2H17 treatment. Finally, we observed the anti-colon cancer effects of L2H17 in vivo. Our data show that compound L2H17 exhibited selective cytotoxic effect on colon cancer cells, via inducing G0/G1 cell cycle arrest and apoptosis in CT26.WT cells. Furthermore, L2H17 treatment decreased cell migration and invasion of CT26.WT cells. In addition, L2H17 possessed marked anti-tumor activity in vivo. The molecular mechanism of L2H17-mediated inhibition of tumor promotion and progression were function through inactivated NF-κB and Akt signaling pathways. All these findings show that L2H17 might be a potential growth inhibitory chalcones derivative for colon cancer cells

Interleukin-17-induced protein lipocalin 2 is dispensable for immunity to oral candidiasis.

Science.gov (United States)

Ferreira, Maria Carolina; Whibley, Natasha; Mamo, Anna J; Siebenlist, Ulrich; Chan, Yvonne R; Gaffen, Sarah L

2014-03-01

Oropharyngeal candidiasis (OPC; thrush) is an opportunistic fungal infection caused by the commensal microbe Candida albicans. Immunity to OPC is strongly dependent on CD4+ T cells, particularly those of the Th17 subset. Interleukin-17 (IL-17) deficiency in mice or humans leads to chronic mucocutaneous candidiasis, but the specific downstream mechanisms of IL-17-mediated host defense remain unclear. Lipocalin 2 (Lcn2; 24p3; neutrophil gelatinase-associated lipocalin [NGAL]) is an antimicrobial host defense factor produced in response to inflammatory cytokines, particularly IL-17. Lcn2 plays a key role in preventing iron acquisition by bacteria that use catecholate-type siderophores, and lipocalin 2(-/-) mice are highly susceptible to infection by Escherichia coli and Klebsiella pneumoniae. The role of Lcn2 in mediating immunity to fungi is poorly defined. Accordingly, in this study, we evaluated the role of Lcn2 in immunity to oral infection with C. albicans. Lcn2 is strongly upregulated following oral infection with C. albicans, and its expression is almost entirely abrogated in mice with defective IL-17 signaling (IL-17RA(-/-) or Act1(-/-) mice). However, Lcn2(-/-) mice were completely resistant to OPC, comparably to wild-type (WT) mice. Moreover, Lcn2 deficiency mediated protection from OPC induced by steroid immunosuppression. Therefore, despite its potent regulation during C. albicans infection, Lcn2 is not required for immunity to mucosal candidiasis.

Tuning the Magnetic Properties and Structural Stabilities of the 2-17-3 Magnets Sm2Fe17X3 (X =C , N) by Substituting La or Ce for Sm

Science.gov (United States)

Pandey, Tribhuwan; Du, Mao-Hua; Parker, David S.

2018-03-01

Designing a permanent magnet with reduced critical rare-earth content is of paramount importance in the development of cost-effective modern technologies. By performing comprehensive first-principles calculations, we investigate the potential avenues for reducing the critical rare-earth content in Sm2Fe17N3 and Sm2Fe17C3 by making a La or Ce substitution for Sm. The calculated magnetic properties of base compounds are in good agreement with the previous low-temperature (4.2-K) experimental measurements, and they show a large axial anisotropy. Although La or Ce substitution results in a slight reduction of magnetic anisotropy, the magnetic moments of Fe atoms mostly remain unchanged. Specifically, large axial anisotropies of 7.2 and 4.1 MJ /m3 are obtained for SmCeFe17 N3 and SmLaFe17 N3 , respectively. These values of anisotropies are comparable to the state-of-the-art permanent magnet Nd2 Fe14 B . The foremost limitation of Sm2 Fe17X3 magnets for practical application is the formation nitrogen or carbon vacancies at high temperatures. By calculating the N- (C)- vacancy formation energy, we show that La or Ce substitution enhances the vacancy formation energy. This enhanced vacancy formation energy will likely improve the thermodynamic stability of these alloys at high temperatures. Therefore, La- or Ce-substituted Sm2Fe17C3 and Sm2Fe17N3 compounds are promising candidates for high-performance permanent magnets with substantially reduced rare-earth content.

Congenital Arthrogryposis: An Extension of the 15q11.2 BP1-BP2 Microdeletion Syndrome?

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K. M. Usrey

2014-01-01

Full Text Available The proximal 15q11–q13 region contains 5 breakpoints (BP1–BP5. The BP1-BP2 region spans approximately 500 kb and contains four evolutionarily conserved genes. The genes in this region are known to play a role in central nervous system development and/or function. Microdeletions within the 15q11.2 BP1-BP2 region have been reported in patients with neurological dysfunction, developmental delays, behavioral problems, and dysmorphic features. We report two unrelated subjects with the 15q11.2 BP1-BP2 microdeletion and presenting with congenital arthrogryposis, a feature which has not been previously reported as part of this newly recognized microdeletion syndrome. While arthrogryposis seen in these two subjects may be coincidental, we propose that congenital arthrogryposis may result from neurological dysfunction and involvement of the microdeletion of the 15q11.2 BP1-BP2 region, further expanding the phenotype of this microdeletion syndrome. We encourage others to report patients with this chromosome microdeletion and neurological findings to further characterize the clinical phenotype.

Mechanical properties of martensitic alloy AISI 422

International Nuclear Information System (INIS)

Huang, F.H.; Hu, W.L.; Hamilton, M.L.

1992-09-01

HT9 is a martensitic stainless steel that has been considered for structural applications in liquid metal reactors (LMRs) as well as in fusion reactors. AISI 422 is a commercially available martensitic stainless steel that closely resembles HT9, and was studied briefly under the auspices of the US LMR program. Previously unpublished tensile, fracture toughness and charpy impact data on AISI 422 were reexamined for potential insights into the consequences of the compositional differences between the two alloys, particularly with respect to current questions concerning the origin of the radiation-induced embrittlement observed in HT9. 8 refs, 8 figs

MAP17 Is a Necessary Activator of Renal Na+/Glucose Cotransporter SGLT2

Science.gov (United States)

Coady, Michael J.; El Tarazi, Abdulah; Santer, René; Bissonnette, Pierre; Sasseville, Louis J.; Calado, Joaquim; Lussier, Yoann; Dumayne, Christopher; Bichet, Daniel G.

2017-01-01

The renal proximal tubule reabsorbs 90% of the filtered glucose load through the Na+-coupled glucose transporter SGLT2, and specific inhibitors of SGLT2 are now available to patients with diabetes to increase urinary glucose excretion. Using expression cloning, we identified an accessory protein, 17 kDa membrane-associated protein (MAP17), that increased SGLT2 activity in RNA-injected Xenopus oocytes by two orders of magnitude. Significant stimulation of SGLT2 activity also occurred in opossum kidney cells cotransfected with SGLT2 and MAP17. Notably, transfection with MAP17 did not change the quantity of SGLT2 protein at the cell surface in either cell type. To confirm the physiologic relevance of the MAP17–SGLT2 interaction, we studied a cohort of 60 individuals with familial renal glucosuria. One patient without any identifiable mutation in the SGLT2 coding gene (SLC5A2) displayed homozygosity for a splicing mutation (c.176+1G>A) in the MAP17 coding gene (PDZK1IP1). In the proximal tubule and in other tissues, MAP17 is known to interact with PDZK1, a scaffolding protein linked to other transporters, including Na+/H+ exchanger 3, and to signaling pathways, such as the A-kinase anchor protein 2/protein kinase A pathway. Thus, these results provide the basis for a more thorough characterization of SGLT2 which would include the possible effects of its inhibition on colocalized renal transporters. PMID:27288013

Neuroprotective Mechanisms of the ACE2-Angiotensin-(1-7)-Mas Axis in Stroke

DEFF Research Database (Denmark)

Bennion, Douglas M; Haltigan, Emily; Regenhardt, Robert W

2015-01-01

The discovery of beneficial neuroprotective effects of the angiotensin converting enzyme 2-angiotensin-(1-7)-Mas axis [ACE2-Ang-(1-7)-Mas] in ischemic and hemorrhagic stroke has spurred interest in a more complete characterization of its mechanisms of action. Here, we summarize findings that desc......The discovery of beneficial neuroprotective effects of the angiotensin converting enzyme 2-angiotensin-(1-7)-Mas axis [ACE2-Ang-(1-7)-Mas] in ischemic and hemorrhagic stroke has spurred interest in a more complete characterization of its mechanisms of action. Here, we summarize findings...... that describe the protective role of the ACE2-Ang-(1-7)-Mas axis in stroke, along with a focused discussion on the potential mechanisms of neuroprotective effects of Ang-(1-7) in stroke. The latter incorporates evidence describing the actions of Ang-(1-7) to counter the deleterious effects of angiotensin II...... complete understanding of the mechanisms of action of Ang-(1-7) to elicit neuroprotection will serve as an essential step toward research into potential targeted therapeutics in the clinical setting....

Synthesis of 4-(3-t-butylamino-2-hydroxypropoxy)- benzimidazol -2 (/sup 11/C)-one (CGP 12177)

Energy Technology Data Exchange (ETDEWEB)

Boullais, C; Crouzel, C; Syrota, A

1986-05-01

4-(3-t-butylamino-2-hydroxypropoxy)-benzimidazol-2 (/sup 11/C)-one (CGP 12177) was synthesized in a short time (30 min) and with a specific activity of 130 mCi/..mu..Mo1 for ..beta.. receptor studies by the positron emission tomography. The radioactive reagent was /sup 11/C-phosgene and the starting material 1-(3-t-butylamino-2-hydroxypropoxy)-2,3-diamino benzene.

Molecular Cloning and Functional Expression of the Equine K+ Channel KV11.1 (Ether à Go-Go-Related/KCNH2 Gene and the Regulatory Subunit KCNE2 from Equine Myocardium.

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Philip Juul Pedersen

Full Text Available The KCNH2 and KCNE2 genes encode the cardiac voltage-gated K+ channel KV11.1 and its auxiliary β subunit KCNE2. KV11.1 is critical for repolarization of the cardiac action potential. In humans, mutations or drug therapy affecting the KV11.1 channel are associated with prolongation of the QT intervals on the ECG and increased risk of ventricular tachyarrhythmia and sudden cardiac death--conditions known as congenital or acquired Long QT syndrome (LQTS, respectively. In horses, sudden, unexplained deaths are a well-known problem. We sequenced the cDNA of the KCNH2 and KCNE2 genes using RACE and conventional PCR on mRNA purified from equine myocardial tissue. Equine KV11.1 and KCNE2 cDNA had a high homology to human genes (93 and 88%, respectively. Equine and human KV11.1 and KV11.1/KCNE2 were expressed in Xenopus laevis oocytes and investigated by two-electrode voltage-clamp. Equine KV11.1 currents were larger compared to human KV11.1, and the voltage dependence of activation was shifted to more negative values with V1/2 = -14.2±1.1 mV and -17.3±0.7, respectively. The onset of inactivation was slower for equine KV11.1 compared to the human homolog. These differences in kinetics may account for the larger amplitude of the equine current. Furthermore, the equine KV11.1 channel was susceptible to pharmacological block with terfenadine. The physiological importance of KV11.1 was investigated in equine right ventricular wedge preparations. Terfenadine prolonged action potential duration and the effect was most pronounced at slow pacing. In conclusion, these findings indicate that horses could be disposed to both congenital and acquired LQTS.

Novel water-air circulation quenching process for AISI 4140 steel

Science.gov (United States)

Zheng, Liyun; Zheng, Dawei; Zhao, Lixin; Wang, Lihui; Zhang, Kai

2013-11-01

AISI 4140 steel is usually used after quenching and tempering. During the heat treatment process in industry production, there are some problems, such as quenching cracks, related to water-cooling and low hardness due to oil quenching. A water-air circulation quenching process can solve the problems of quenching cracks with water and the high cost quenching with oil, which is flammable, unsafe and not enough to obtain the required hardness. The control of the water-cooling and air-cooling time is a key factor in the process. This paper focuses on the quenching temperature, water-air cycle time and cycle index to prevent cracking for AISI 4140 steel. The optimum heat treatment parameters to achieve a good match of the strength and toughness of AISI 4140 steel were obtained by repeated adjustment of the water-air circulation quenching process parameters. The tensile strength, Charpy impact energy at -10 °C and hardness of the heat treated AISI 4140 steel after quenching and tempering were approximately 1098 MPa, 67.5 J and 316 HB, respectively.

17 CFR 2.3 - Prohibitions against misuse of seal.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Prohibitions against misuse of seal. 2.3 Section 2.3 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION OFFICIAL... character, or with wrongful or fraudulent intent, using, buying, procuring, selling or transferring to...

Linking Endotoxins, African Dust PM10 and Asthma in an Urban and Rural Environment of Puerto Rico

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Mario G. Ortiz-Martínez

2015-01-01

Full Text Available African Dust Events (ADE are a seasonal phenomenon that has been suggested to exacerbate respiratory and proinflammatory diseases in Puerto Rico (PR. Increases in PM10 concentration and the effects of biological endotoxins (ENX are critical factors to consider during these storms. ENX promote proinflammatory responses in lungs of susceptible individuals through activation of the Toll-like receptors (TLR2/4 signaling pathways. The objective of the study was to evaluate the toxicological and proinflammatory responses stimulated by ADE PM10 ENX reaching PR using human bronchial epithelial cells. PM10 organic extracts from a rural and urban site in PR (March 2004 were obtained from ADE and non-ADE and compared. A retrospective data analysis (PM10 concentration, aerosol images, and pediatric asthma claims was performed from 2000 to 2012 with particular emphasis in 2004 to classify PM samples. Urban extracts were highly toxic, proinflammatory (IL-6/IL-8 secretion, and induced higher TLR4 expression and NF-κB activation compared to rural extracts. ENX were found to contribute to cytotoxicity and inflammatory responses provoked by urban ADE PM10 exposure suggesting a synergistic potency of local and natural ENX incoming from ADE. The contribution of ADE PM10 ENX is valuable in order to understand interactions and action mechanisms of airborne pollutants as asthma triggers in PR.

Radiosynthesis of the D2/3 agonist [3-11C]-(+)-PHNO using [11C]iodomethane

International Nuclear Information System (INIS)

Francisco Garcia-Arguello, Segundo; Fortt, Robin; Steel, Colin J.; Brickute, Diana; Glaser, Matthias; Turton, David R.; Robins, Edward G.; Årstad, Erik; Luthra, Sajinder K.

2013-01-01

We report here a radiosynthesis for the D 2/3 agonist (+)-4-([3- 11 C]propyl)-3,4,4a,5,6,10b-hexahydro-2H-naphtho[1,2-b][1,4] oxazin-9-ol (3-[ 11 C]-(+)-PHNO) labelled at the terminal carbon of the N-propyl chain. The protocol is based on 11 C-methylation of an N-acetyl precursor. This initial step is followed by a reduction with LiAlH 4 to give ([3- 11 C]-(+)-PHNO). We first applied the method for the synthesis of a model compound, N-3-([ 11 C]propyl)-1,2,3,4-tetrahydroisoquinoline, which we obtained in 77–97% analytical radiochemical yield (n=6) in 20 min. Similarly, we prepared ([3- 11 C]-(+)-PHNO) in 55–60% analytical radiochemical yield (n=5) using a one-pot procedure. We have also been able to implement the complete process on a semi-automated module. This platform delivered purified and formulated [3- 11 C]PHNO with an average radiochemical yield of 9% (n=13, range 2–30%, non-decay corrected), a radiochemical purity >95%, and a specific radioactivity of 26.8–81.1 GBq/μmol in a total time of 63–65 min. - Highlights: ► We report an alternative method to obtain carbon-11 labelled PHNO. ► The method is based on readily available [ 11 C]methyl iodide as starting material. ► We have automated the alkylation/reduction protocol including purification and formulation

Evaluation of the mechanical properties of SA 333 Gr.6, AISI 304 and Zr-2.5% Nb through Automated Ball Indentation (ABI) technique

International Nuclear Information System (INIS)

Balakrishnan, K.S.; Rath, B.N.; Shriwastaw, R.S.; Ramadasan, E.; Kulkarni, R.V.; Sahoo, K.C.

2009-08-01

Automated Ball Indentation (ABI) technique has been employed in evaluating the tensile property data on three materials, namely SA333 Gr.6 carbon steel (used as PHT piping), AISI 304 (used as calandria vessel) and Zr-2.5% Nb (used as coolant tube) in Pressurised Heavy Water Reactors (PHWRs) with a view to exploring the applicability of ABI technique in providing reliable mechanical property data. The exercise was carried out in cooperation with a second laboratory where conventional tension tests alone were conducted such that the output of the study could be independently monitored and evaluated in an unbiased manner. The results generated in the authors' laboratory were found to be fully in agreement with what were obtained through conventional tension tests. Thus the study has been successful in establishing the reliability of the data obtained through miniature route especially in the case of coolant tube which has immense applications. (author)

Passivity of AISI 321 stainless steel in 0.5 M H2SO4 solution studied by Mott–Schottky analysis in conjunction with the point defect model

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A. Fattah-alhosseini

2016-11-01

Full Text Available The passivity of AISI 321 stainless steel in 0.5 M H2SO4 solution, in the steady-state condition, has been explored using electrochemical impedance spectroscopy (EIS and Mott–Schottky analysis. Based on the Mott–Schottky analysis in conjunction with the point defect model (PDM, it was shown that the calculated donor density decreases exponentially with increasing passive film formation potential. The thickness of the passive film was increased linearly with the formation potential. These observations were consistent with the predictions of the PDM, noting that the point defects within the passive film are metal interstitials, oxygen vacancies, or both.

9 CFR 2.11 - Denial of initial license application.

Science.gov (United States)

2010-01-01

... have violated any Federal, State, or local laws or regulations pertaining to animal cruelty within 1... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Denial of initial license application. 2.11 Section 2.11 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT...

Combustion synthesis of micron-sized Sm2Co17 particles via mechanochemical processing

International Nuclear Information System (INIS)

Liu, W.; McCormick, P.G.

1998-01-01

Full text: The spontaneous formation of Sm 2 Co 17 micron-sized particles via a mechanically induced combustion reaction has been investigated. Sm 2 Co 17 alloy particles of 0.1--2 μm in size embedded in a CaO matrix formed directly via a combustion reaction induced by milling the powder mixture of Sm 2 O 3 , CoO, CaO and Ca over a critical time. The micron-sized Sm 2 Co 17 particles were found to have the TbCu 7 -type structure and characterized by a coercivity value of 7.8 kOe while embedded in the CaO matrix. The effect of subsequent heat treatment on the structure and magnetic properties of as-milled samples was also investigated. Removal of the CaO by a carefully controlled washing process yielded micron-sized Sm 2 Co 17 particles without significant oxidation of the particles. These fine Sm 2 Co 17 particles can be used to produce anisotropic bulk or bonded magnets

17O solid-state NMR spectroscopy of A2B2O7 oxides: quantitative isotopic enrichment and spectral acquisition?

Science.gov (United States)

Fernandes, Arantxa; Moran, Robert F; Sneddon, Scott; Dawson, Daniel M; McKay, David; Bignami, Giulia P M; Blanc, Frédéric; Whittle, Karl R; Ashbrook, Sharon E

2018-02-13

The potential of 17 O NMR spectroscopy for the investigation of A 2 B 2 O 7 ceramic oxides important in the encapsulation of radioactive waste is demonstrated, with post-synthetic enrichment by exchange with 17 O 2 gas. For Y 2 Sn 2 O 7 , Y 2 Ti 2 O 7 and La 2 Sn 2 O 7 pyrochlores, enrichment of the two distinct O species is clearly non quantitative at lower temperatures (∼700 °C and below) and at shorter times, despite these being used in prior work, with preferential enrichment of OA 2 B 2 favoured over that of OA 4 . At higher temperatures, the 17 O NMR spectra suggest that quantitative enrichment has been achieved, but the integrated signal intensities do not reflect the crystallographic 1 : 6 (O1 : O2) ratio until corrected for differences in T 1 relaxation rates and, more importantly, the contribution of the satellite transitions. 17 O NMR spectra of Y 2 Zr 2 O 7 and Y 2 Hf 2 O 7 defect fluorites showed little difference with any variation in enrichment temperature or time, although an increase in the absolute level of enrichment (up to ∼7.5%) was observed at higher temperature. DFT calculations show that the six distinct resonances observed cannot be assigned unambiguously, as each has contributions from more than one of the five possible next nearest neighbour environments. For La 2 Ti 2 O 7 , which adopts a layered perovskite-like structure, little difference in the spectral intensities is observed with enrichment time or temperature, although the highest absolute levels of enrichment (∼13%) were obtained at higher temperature. This work demonstrates that 17 O NMR has the potential to be a powerful probe of local structure and disorder in oxides, but that considerable care must be taken both in choosing the conditions for 17 O enrichment and the experimental acquisition parameters if the necessary quantitative measurements are to be obtained for more complex systems.

INTERPRETING THE SUBTLE SPECTRAL VARIATIONS OF THE 11.2 AND 12.7 μ m POLYCYCLIC AROMATIC HYDROCARBON BANDS

International Nuclear Information System (INIS)

Shannon, M. J.; Stock, D. J.; Peeters, E.

2016-01-01

We report new properties of the 11 and 12.7 μ m emission complexes of polycyclic aromatic hydrocarbons (PAHs) by applying a Gaussian-based decomposition technique. Using high-resolution Spitzer Space Telescope data, we study in detail the spectral and spatial characteristics of the 11 and 12.7 μ m emission bands in maps of reflection nebulae NGC 7023 and NGC 2023 (north and south) and the star-forming region M17. Profile variations are observed in both the 11 and 12.7 μ m emission bands. We identify a neutral contribution to the traditional 11.0 μ m PAH band and a cationic contribution to the traditional 11.2 μ m band, the latter of which affects the PAH class of the 11.2 μ m emission in our sample. The peak variations of the 12.7 μ m complex are explained by the competition between two underlying blended components. The spatial distributions of these components link them to cations and neutrals. We conclude that the 12.7 μ m emission originates in both neutral and cationic PAHs, lending support to the use of the 12.7/11.2 intensity ratio as a charge proxy.

INTERPRETING THE SUBTLE SPECTRAL VARIATIONS OF THE 11.2 AND 12.7 μ m POLYCYCLIC AROMATIC HYDROCARBON BANDS

Energy Technology Data Exchange (ETDEWEB)

Shannon, M. J.; Stock, D. J.; Peeters, E., E-mail: mshann3@uwo.ca [Department of Physics and Astronomy, University of Western Ontario, London, ON, N6A 3K7 (Canada)

2016-06-20

We report new properties of the 11 and 12.7 μ m emission complexes of polycyclic aromatic hydrocarbons (PAHs) by applying a Gaussian-based decomposition technique. Using high-resolution Spitzer Space Telescope data, we study in detail the spectral and spatial characteristics of the 11 and 12.7 μ m emission bands in maps of reflection nebulae NGC 7023 and NGC 2023 (north and south) and the star-forming region M17. Profile variations are observed in both the 11 and 12.7 μ m emission bands. We identify a neutral contribution to the traditional 11.0 μ m PAH band and a cationic contribution to the traditional 11.2 μ m band, the latter of which affects the PAH class of the 11.2 μ m emission in our sample. The peak variations of the 12.7 μ m complex are explained by the competition between two underlying blended components. The spatial distributions of these components link them to cations and neutrals. We conclude that the 12.7 μ m emission originates in both neutral and cationic PAHs, lending support to the use of the 12.7/11.2 intensity ratio as a charge proxy.

Capturing [11C]CO2 for use in aqueous applications

International Nuclear Information System (INIS)

Vandehey, Nicholas T.; O’Neil, James P.

2014-01-01

We present a simple method for trapping [ 11 C]CO 2 gas and releasing it into a buffered solution using an ion-exchange cartridge. Sodium hydroxide cartridges captured >99% of [ 11 C]CO 2 following NaOH activation. A sodium bicarbonate solution eluted >99% of trapped radioactivity. Trapping [ 11 C]CO 2 directly in small volumes of several solutions was less effective than cartridge methods. The recommended methods allow for fast and simple production of highly concentrated carbon-11 containing aqueous solutions for use in filling phantoms, calibrating detectors, or (bio)geochemical experiments. - Highlights: • An ion exchange resin can trap [ 11 C]CO 2 gas and release it with saturated bicarbonate. • Elution from cartridge requires as little as 300 µL volume, with eluant at pH=10. • SPE trap-and-release provided better results than trapping in solution

(2-Pyridyl[5-(2-pyridylcarbonyl-2-pyridyl]methanone

Directory of Open Access Journals (Sweden)

Zi-jia Wang

2010-10-01

Full Text Available In the centrosymmetric title compound, C17H11N3O2, the dihedral angle between the central and pendant pyridyl rings is 50.29 (9°. In the crystal, molecules stack along the a axis by π–π interactions between the pyridine rings with centroid–centroid distances of 3.845 (2 Å. The N atom and one of the C atoms of the central ring are disordered by symmetry.

Changes of surface layer of nitrogen-implanted AISI316L stainless steel

International Nuclear Information System (INIS)

Budzynski, P.; Polanski, K.; Kobzev, A.P.

2007-01-01

The effects of nitrogen ion implantation into AISI316L stainless steel on friction, wear, and microhardness have been investigated at an energy level of 125 keV at a fluence of 1·10 17 - 1·10 18 N/cm 2 . The composition of the surface layer was investigated by RBS, XRD (GXRD), SEM and EDX. The friction coefficient and abrasive wear rate of the stainless steel were measured in the atmospheres of air, oxygen, argon, and in vacuum. As follows from the investigations, there is an increase in resistance to frictional wear in the studied samples after implantation; however, these changes are of different characters in various atmospheres. The largest decrease in wear was observed during tests in the air, and the largest reduction in the value of the friction coefficient for all implanted samples was obtained during tests in the argon atmosphere. Tribological tests revealed larger contents of nitrogen, carbon, and oxygen in the products of surface layer wear than in the surface layer itself of the sample directly after implantation

Synthesis of dimethyl-1,1 guanylguanidine-{sup 14}C-2,4 (dimethyl-1-1 biguanide) hydrochloride; Synthese du chlorhydrate de dimethyl-1,1 guanylguanidine {sup 14}C-2,4 (dimethyl-1-1 biguanide)

Energy Technology Data Exchange (ETDEWEB)

Herbert, M; Pichat, L [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1961-07-01

A description of the synthesis of dimethyl-1,1 guanylguanidine-{sup 14}C-2,4 hydrochloride passing through the {sup 14}C{sub 2} dicyandiamide. The overall yield with respect to Ba{sup 14}CO{sub 3} is 38 per cent. (author) [French] Description de la synthese du chlorhydrate de dimethyl-1,1 guanylguanidine {sup 14}C-2,4 par l'intermediaire de la dicyandiamide {sup 14}C{sub 2}. Le rendement global par rapport a {sup 14}CO{sub 3}Ba est de 38 pour cent. (auteur)

X-ray bursts from GX 17+2: a new approach

International Nuclear Information System (INIS)

Sztajno, M.; Langmeier, A.; Truemper, J.; Pietsch, W.; Paradijs, J. van; Lewin, W.H.G.; Massachusetts Inst. of Tech., Cambridge

1986-01-01

The detection of two X-ray bursts from GX 17+2 is reported; a short one (lasting about 10s), and a long one (which lasted about 5 min). These bursts reached a maximum intensity of only about 40 per cent above the persistent flux level. Like previous long bursts observed from GX 17+2 the long burst showed little softening during its decay, and it is difficult at first glance to classify it as either a type 1 or a type 2 burst. Following the recent results of two of the authors a time-dependent spectral analysis of these bursts has been made. (author)

Effect of vanadium carbide on dry sliding wear behavior of powder metallurgy AISI M2 high speed steel processed by concentrated solar energy

Energy Technology Data Exchange (ETDEWEB)

García, C. [Materials Engineering. E.I.I., Universidad de Valladolid. C/Paseo del cauce 59, 47011 Valladolid (Spain); Romero, A. [E.T.S. Ingenieros Industriales. Instituto de Investigaciones Energéticas y Aplicaciones Industriales (INEI). Universidad de Castilla-La Mancha, Edificio Politécnico, Avda. Camilo José Cela s/n, 13071 Ciudad Real (Spain); Herranz, G., E-mail: gemma.herranz@uclm.es [E.T.S. Ingenieros Industriales. Instituto de Investigaciones Energéticas y Aplicaciones Industriales (INEI). Universidad de Castilla-La Mancha, Edificio Politécnico, Avda. Camilo José Cela s/n, 13071 Ciudad Real (Spain); Blanco, Y.; Martin, F. [Materials Engineering. E.I.I., Universidad de Valladolid. C/Paseo del cauce 59, 47011 Valladolid (Spain)

2016-11-15

Mixtures of AISI M2 high speed steel and vanadium carbide (3, 6 or 10 wt.%) were prepared by powder metallurgy and sintered by concentrated solar energy (CSE). Two different powerful solar furnaces were employed to sinter the parts and the results were compared with those obtained by conventional powder metallurgy using a tubular electric furnace. CSE allowed significant reduction of processing times and high heating rates. The wear resistance of compacts was studied by using rotating pin-on-disk and linearly reciprocating ball-on-flat methods. Wear mechanisms were investigated by means of scanning electron microscopy (SEM) observations and chemical inspections of the microstructures of the samples. Better wear properties than those obtained by conventional powder metallurgy were achieved. The refinement of the microstructure and the formation of carbonitrides were the reasons for this. - Highlights: •Powder metallurgy of mixtures of M2 high speed steel and VC are studied. •Some sintering is done by concentrated solar energy. •Rotating pin-on-disk and linearly reciprocating ball-on-flat methods are used. •The tribological properties and wear mechanisms, under dry sliding, are studied.

FGF‐2 promotes osteocyte differentiation through increased E11/podoplanin expression

Science.gov (United States)

Ikpegbu, Ekele; Basta, Lena; Clements, Dylan N.; Fleming, Robert; Vincent, Tonia L.; Buttle, David J.; Pitsillides, Andrew A.; Farquharson, Colin

2018-01-01

E11/podoplanin is critical in the early stages of osteoblast‐to‐osteocyte transitions (osteocytogenesis), however, the upstream events which regulate E11 expression are unknown. The aim of this study was to examine the effects of FGF‐2 on E11‐mediated osteocytogenesis and to reveal the nature of the underlying signaling pathways regulating this process. Exposure of MC3T3 osteoblast‐like cells and murine primary osteoblasts to FGF‐2 (10 ng/ml) increased E11 mRNA and protein expression (p 70% reduction of basal E11 mRNA expression (p < 0.05) and effectively abrogated FGF‐2‐related changes in E11 expression and dendrite formation. FGF‐2 strongly activated the ERK signaling pathway in osteoblast‐like cells but inhibition of this pathway did not block the ability of FGF‐2 to enhance E11 expression or to promote acquisition of the osteocyte phenotype. The results of this study highlight a novel mechanism by which FGF‐2 can regulate osteoblast differentiation and osteocyte formation. Specifically, the data suggests that FGF‐2 promotes osteocytogenesis through increased E11 expression and further studies will identify if this regulatory pathway is essential for bone development and maintenance in health and disease. PMID:29215722

Mono-(2-ethylhexyl) phthalate (MEHP) regulates glucocorticoid metabolism through 11β-hydroxysteroid dehydrogenase 2 in murine gonadotrope cells

International Nuclear Information System (INIS)

Hong, Dun; Li, Xing-Wang; Lian, Qing-Quan; Lamba, Pankaj; Bernard, Daniel J.; Hardy, Dianne O.; Chen, Hai-Xiao; Ge, Ren-Shan

2009-01-01

Di-(2-ethylhexyl) phthalate (DEHP) and its metabolite mono-(2-ethylhexyl) phthalate (MEHP) have been classified as toxicants to the reproductive system at the testis level and DEHP may also impair reproductive axis function at the pituitary levels. However, MEHP is 10-fold more potent than DEHP in toxicity and little is known about the toxicological effect of MEHP on pituitary. In this study, we demonstrated that 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), not 11β-HSD1, is strongly expressed in murine gonadotrope LβT2 cells. Interestingly, MEHP inhibited Hsd11b2 mRNA level and 11β-HSD2 enzyme activity in LβT2 cells at as low as 10 -7 M. Corticosterone (CORT) at a concentration of 10 -6 M significantly inhibited LβT2 cell proliferation after 2-day culture, and 10 -6 M RU486, an antagonist of glucocorticoid receptor (GR), reversed this inhibition. However, in the presence of 10 -5 or 10 -4 M MEHP, the minimal concentration of CORT to inhibit the proliferation of LβT2 cells was lowered to 10 -7 M, and 10 -6 M RU486 was not able to completely reverse the CORT effect. In conclusion, along with the regulation of GR, 11β-HSD2 may have a key role in glucocorticoid metabolism in LβT2 cells. MEHP may participate in the glucocorticoid metabolism in LβT2 cells through inhibition of 11β-HSD2 enzyme activity. Such perturbation may be of pathological significance as MEHP may interfere with the reproductive system at pituitary level through regulation of glucocorticoid metabolism, especially in neonates with higher risk of phthalates exposure.

Electrochemical investigation of 2,2-dinitroethene-1,1-diamine (FOX-7) in aqueous media

Czech Academy of Sciences Publication Activity Database

Šimková, Ludmila; Klíma, Jiří; Sazama, Petr; Ludvík, Jiří

2011-01-01

Roč. 15, č. 10 (2011), s. 2133-2139 ISSN 1432-8488 R&D Projects: GA MŠk ME09002 Institutional research plan: CEZ:AV0Z40400503 Keywords : 2,2-dinitroethene-11-diamine * FOX -7 * reduction Subject RIV: CG - Electrochemistry Impact factor: 2.131, year: 2011

2α + t cluster state in 11B

International Nuclear Information System (INIS)

Kawabata, T; Akimune, H; Fujita, H; Fujita, Y; Fujiwara, M; Hara, K; Hatanaka, K; Itoh, M; Kanada-En'yo, Y; Kishi, S; Nakanishi, K; Sakaguchi, H; Shimbara, Y; Tamii, A; Terashima, S; Uchida, M; Wakasa, T; Yasuda, Y; Yoshida, H P; Yosoi, M

2006-01-01

The cluster structures of the excited states in 11 B are studied by analyzing the isoscalar monopole and quadrupole strengths in the 11 B(d, d') reaction at E d = 200 MeV. The excitation strengths are compared with the theoretical predictions by the antisymmetrized molecular-dynamics (AMD) calculations. It is found that the large monopole strength for the 3/2 - 3 state at E x = 8.56 MeV is well described by the AMD wave function with a dilute 2α + tcluster structure

Development of potent and selective inhibitors of 17β-hydroxysteroid dehydrogenase type 2 : a new target for the treatment of osteoporosis

OpenAIRE

Wetzel, Marie

2011-01-01

Using a ligand-based approach, we designed and synthesised novel non-steroidal 17beta-HSD2 inhibitors from two scaffolds described in literature as potential drugs for the treatment of osteoporosis. These compounds bear a hydrophobic core and two polar moieties, distant from each other circa 11Å, mimicking the two hydroxy group at the C3 and C17 position of the steroid E2. The best OH-OH substitution pattern was first elucidated in an optimisation process. Addition of further substituents to ...

Wear behavior of the surface alloyed AISI 1020 steel with Fe-Nb-B by TIG welding technique

Science.gov (United States)

Kilinc, B.; Durmaz, M.; Abakay, E.; Sen, U.; Sen, S.

2015-03-01

Weld overlay coatings also known as hardfacing is a method which involves melting of the alloys and solidification for applied coatings. Recently hardfacing by welding has become a commonly used technique for improvement of material performance in extreme (high temperature, impact/abrasion, erosion, etc.) conditions.In the present study, the coatings were produced from a mixture of ferrous niobium, ferrous boron and iron powders in the ranges of -45µm particle size with different ratio. Fe12Nb5B3 and Fe2NbBalloys were coated on the AISI 1020 steel surface by TIG welding. The phases formed in the coated layer are Fe2B, NbB2, NbFeB and Fe0,2 Nb0,8 phases. The hardness of the presence phases are changing between 1689±85 HV0.01, and 181±7 HV0.1. Microstructural examinations were realized by optical and scanning electron microscopy. The wear and friction behaviors of Fe12Nb5B3 and Fe2NbB realized on the AISI 1020 steel were investigated by the technique of TIG welding by using ball-on-disk arrangement against alumina ball.

High field magnetization process of (Sm, Nd)2Fe17Ny compounds

International Nuclear Information System (INIS)

Yu, M.J.; Tang, N.; Liu, Y.L.; Tegus, O.; Lu, Y.; Kuang, J.P.; Yang, F.M.; Li, X.; Zhou, G.F.; Boer, F.R. de

1992-01-01

The crystal structure and high-field magnetization process of (Sm 1-x Nd x ) 2 Fe 17 N y compounds (x = 0.0, 0.1, ..., 1.0, 2 1-x Nd x ) 2 Fe 17 N y compounds were found to crystallize in the rhombohedral Th 2 Zn 17 structure. As x increases, the Curie temperature decreases. The anisotropy fields and easy magnetization direction were investigated from 1.5 K to room temperature by means of high-field magnetization measurements and AC-susceptibility measurements, combined with X-ray diffraction on random and magnetically aligned powder samples. The anisotropy field decreases with increasing x and approaches a minimum value at about x = 0.6, then increases again. A tentative spin phase diagram for the (Sm 1-x Nd x ) 2 Fe 17 N y series is presented. At room temperature, the easy magnetization direction remains along the c-axis up to x = 0.6. (orig.)

Cocrystals of the antimalarial drug 11-azaartemisinin with three alkenoic acids of 1:1 or 2:1 stoichiometry.

Science.gov (United States)

Nisar, Madiha; Wong, Lawrence W Y; Sung, Herman H Y; Haynes, Richard K; Williams, Ian D

2018-06-01

The stoichiometry, X-ray structures and stability of four pharmaceutical cocrystals previously identified from liquid-assisted grinding (LAG) of 11-azaartemisinin (11-Aza; systematic name: 1,5,9-trimethyl-14,15,16-trioxa-11-azatetracyclo[10.3.1.0 4,13 .0 8,13 ]hexadecan-10-one) with trans-cinnamic (Cin), maleic (Mal) and fumaric (Fum) acids are herein reported. trans-Cinnamic acid, a mono acid, forms 1:1 cocrystal 11-Aza:Cin (1, C 15 H 23 NO 4 ·C 9 H 8 O 2 ). Maleic acid forms both 1:1 cocrystal 11-Aza:Mal (2, C 15 H 23 NO 4 ·C 4 H 4 O 4 ), in which one COOH group is involved in self-catenation, and 2:1 cocrystal 11-Aza 2 :Mal (3, 2C 15 H 23 NO 4 ·C 4 H 4 O 4 ). Its isomer, fumaric acid, only affords 2:1 cocrystal 11-Aza 2 :Fum (4). All cocrystal formation appears driven by acid-lactam R 2 2 (8) heterosynthons with short O-H...O=C hydrogen bonds [O...O = 2.56 (2) Å], augmented by weaker C=O...H-N contacts. Despite a better packing efficiency, cocrystal 3 is metastable with respect to 2, probably due to a higher conformational energy for the maleic acid molecule in its structure. In each case, the microcrystalline powders from LAG were useful in providing seeding for the single-crystal growth.

Crystal structures of the 2:2 complex of 1,1′-(1,2-phenylenebis(3-m-tolylurea and tetrabutylammonium chloride or bromide

Directory of Open Access Journals (Sweden)

Chao Huang

2017-09-01

Full Text Available The title compounds, tetrabutylammonium chloride–1,1′-(1,2-phenylenebis(3-m-tolylurea (1/1, C16H36N+·Cl−·C22H22N4O2 or [(n-Bu4N+·Cl−(C22H22N4O2] (I and tetrabutylammonium bromide–1,1′-(1,2-phenylenebis(3-m-tolylurea (1/1, C16H36N+·Br−·C22H22N4O2 or [(n-Bu4N+·Br−(C22H22N4O2] (II, both comprise a tetrabutylammonium cation, a halide anion and an ortho-phenylene bis-urea molecule. Each halide ion shows four N—H...X (X = Cl or Br interactions with two urea receptor sites of different bis-urea moieties. A crystallographic inversion centre leads to the formation of a 2:2 arrangement of two halide anions and two bis-urea molecules. In the crystals, the dihedral angle between the two urea groups of the bis-urea molecule in (I [defined by the four N atoms, 165.4 (2°] is slightly smaller than that in (II [167.4 (2°], which is probably due to the smaller ionic radius of chloride compared to bromide.

Characterisation of Pristine and Recoated electron beam evaporation plasma-assisted physical vapour deposition Cr-N coatings on AISI M2 steel and WC-Co substrates

International Nuclear Information System (INIS)

Avelar-Batista, J.C.; Spain, E.; Housden, J.; Fuentes, G.G.; Rebole, R.; Rodriguez, R.; Montala, F.; Carreras, L.J.; Tate, T.J.

2005-01-01

This paper is focussed on the characterisation of electron beam evaporation plasma-assisted physical vapour deposition Cr-N coatings deposited on AISI M2 steel and hardmetal (K10) substrates in two different conditions: Pristine (i.e., coated) and Recoated (i.e., stripped and recoated). Analytical methods, including X-ray diffraction (XRD), scanning electron microscopy, scratch adhesion and pin-on-disc tests were used to evaluate several coating properties. XRD analyses indicated that both Pristine and Recoated coatings consisted of a mixture of hexagonal Cr 2 N and cubic CrN, regardless of substrate type. For the M2 steel substrate, only small differences were found in terms of coating phases, microstructure, adhesion, friction and wear coefficients between Pristine and Recoated. Recoated on WC-Co (K10) exhibited a less dense microstructure and significant inferior adhesion compared to Pristine on WC-Co (K10). The wear coefficient of Recoated on WC-Co was 100 times higher than those exhibited by all other specimens. The results obtained confirm that the stripping process did not adversely affect the Cr-N properties when this coating was deposited onto M2 steel substrates, but it is clear from the unsatisfactory tribological performance of Recoated on WC-Co that the stripping process is unsuitable for hardmetal substrates

Skeleton polyhedral rearrangements of 8-alkyl-7,9-dicarba-nido-undecaborate(-1) anion to 11-alkyl-2,7-dicarba-nido-undecaborane(13) and to 9-alkyl-7,8-dicarba-nido-undecaborate(-1) anion. Molecular structure of 2,7-Me2-11-PhCH2-2,7-C2B9H10

International Nuclear Information System (INIS)

Zakharkin, K.I.; Zhigareva, G.G.; Antonovich, V.A.; Yanovskij, A.I.; Struchkov, Yu.T.

1986-01-01

Using the methods of 1 H and 11 B NMR-spectroscopy and X-ray diffraction analysis skeleton polyhedral rearrangements of carboranes are studied. During protonation of anion 8-R-7, 9-R' 2 -7, 9-C 2 B 9 H 9 - the skeleton polyhedral rearrangement in the series of nido-carboranes, resulting in 2,7-R' 2 -11-R-2, 7-C 2 B 9 H 10 (R=Me, PhCH 2 , R'=H, Me) is observed. The rearrangement is reversible. On the detachment of two protons from 2,7-Me 2 -11-PhCH 2 -2,7-C 2 B 9 H 10 and during subsequent protonation the skeleton polyhedral rearrangement with the formation of anion 9-PhCH 2 -7,8-Me 2 -7,8-C 2 B 9 H 9 - takes place

11 CFR 9003.2 - Candidate certifications.

Science.gov (United States)

2010-01-01

... funds under 11 CFR 9003.2(c)(3) shall not count against such candidate's $50,000 expenditure limitation... expenditures. (8) Expenditures made using a credit card for which the candidate is jointly or solely liable will count against the limits of this section to the extent that the full amount due, including any...

Wear resistance of AISI 304 stainless steel submitted to low temperature plasma carburizing

Directory of Open Access Journals (Sweden)

Marcos Antônio Barcelos

Full Text Available Abstract Despite the AISI 304 stainless steel has high corrosion/oxidation resistance, its tribological properties are poor, being one of the barriers for use in severe wear applications. Thus, there is a wide field for studying technologies that aim to increase the surface hardness and wear resistance of this material. In this work, hardness and wear resistance for AISI 304 stainless steel submitted to the thermochemical treatment by low temperature plasma carburizing (LTPC in a fixed gas mixture composition of 93% H2 and 7% CH4 are presented. Through the evaluation of the carburizing layers, it was possible to observe a substantial improvement in tribological properties after all temperature and time of treatment. This improvement is directly related to the increase of the process variables; among them temperature has a stronger influence on the wear resistance obtained using LTPC process.

Micro-Abrasion Wear Resistance of Borided 316L Stainless Steel and AISI 1018 Steel

Science.gov (United States)

Reséndiz-Calderon, C. D.; Rodríguez-Castro, G. A.; Meneses-Amador, A.; Campos-Silva, I. E.; Andraca-Adame, J.; Palomar-Pardavé, M. E.; Gallardo-Hernández, E. A.

2017-11-01

The 316L stainless steel has high corrosion resistance but low tribological performance. In different industrial sectors (biomedical, chemical, petrochemical, and nuclear engineering), improvement upon wear resistance of 316L stainless steel components using accessible and inexpensive methods is critical. The AISI 1018 steel is widely used in industry, but its tribological performance is not the best among steels. Therefore, in this study the behavior of the borided 316L stainless steel and 1018 steel is evaluated under micro-abrasion wear. The boriding was carried out at 1223 K over 6 h of exposure time, resulting in a biphase layer composed of FeB/Fe2B phases. In order to evaluate Fe2B phase with no influence from FeB phase, AISI 1018 steel samples were borided at 1273 K for over 20 min and then diffusion annealed at 1273 K over 2 h to obtain a Fe2B mono-phase layer. Micro-abrasion wear resistance was evaluated by a commercial micro-abrasion testing rig using a mix of F-1200 SiC particles with deionized water as abrasive slurry. The obtained wear rates for FeB and Fe2B phases and for the 316L stainless steel were compared. Wear resistance of 316L stainless steel increases after boriding. The wear mechanisms for both phases and for the stainless steel were identified. Also, transient conditions for rolling and grooving abrasion were determined for the FeB and Fe2B phases.

FGF-2 promotes osteocyte differentiation through increased E11/podoplanin expression.

Science.gov (United States)

Ikpegbu, Ekele; Basta, Lena; Clements, Dylan N; Fleming, Robert; Vincent, Tonia L; Buttle, David J; Pitsillides, Andrew A; Staines, Katherine A; Farquharson, Colin

2018-07-01

E11/podoplanin is critical in the early stages of osteoblast-to-osteocyte transitions (osteocytogenesis), however, the upstream events which regulate E11 expression are unknown. The aim of this study was to examine the effects of FGF-2 on E11-mediated osteocytogenesis and to reveal the nature of the underlying signaling pathways regulating this process. Exposure of MC3T3 osteoblast-like cells and murine primary osteoblasts to FGF-2 (10 ng/ml) increased E11 mRNA and protein expression (p 70% reduction of basal E11 mRNA expression (p < 0.05) and effectively abrogated FGF-2-related changes in E11 expression and dendrite formation. FGF-2 strongly activated the ERK signaling pathway in osteoblast-like cells but inhibition of this pathway did not block the ability of FGF-2 to enhance E11 expression or to promote acquisition of the osteocyte phenotype. The results of this study highlight a novel mechanism by which FGF-2 can regulate osteoblast differentiation and osteocyte formation. Specifically, the data suggests that FGF-2 promotes osteocytogenesis through increased E11 expression and further studies will identify if this regulatory pathway is essential for bone development and maintenance in health and disease. © 2017 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc.

Tracer kinetics of plants carbon allocation with continuously produced 11CO2

International Nuclear Information System (INIS)

Fares, Y.; Goeschl, J.D.; Magnuson, C.E.; Strain, B.R.

1988-01-01

Parameters of carbon allocation dynamics in plants were measured using 11 CO 2 and tracer kinetics techniques. Mechanical agitation reduced carbon export rate (CER) by 33% in cotton seedling's leaf, while storage rate and export pool size increased. Carbon storage and export rates of C 4 bunch grasses were higher in the afternoon than in the morning in spite of the decrease in CER. Water stress of cotton seedlings caused reduction in CER, and increase in exportable products concentrations and rate of storage. By the third stress day, measurable decreases in CER, transpiration, export rate and export pool size were recorded. (author) 17 refs.; 8 figs.; 1 tab

A Chemical Activation Study of the Unimolecular Reactions of CD3CD2CHCl2 and CHCl2CHCl2 with Analysis of the 1,1-HCl Elimination Pathway.

Science.gov (United States)

Larkin, Allie C; Nestler, Matthew J; Smith, Caleb A; Heard, George L; Setser, Donald W; Holmes, Bert E

2016-10-03

Chemically activated C2D5CHCl2 molecules were generated with 88 kcal mol-1 of vibrational energy by the recombination of C2D5 and CHCl2 radicals in a room temperature bath gas. The competing 2,1-DCl and 1,1-HCl unimolecular reactions were identified by the observation of the CD3CD=CHCl and CD3CD=CDCl products. The initial CD3CD2C-Cl carbene product from 1,1-HCl elimination rearranges to CD3CD=CDCl under the conditions of the experiments. The experimental rate constants were 2.7 x107 and 0.47 x107 s-1 for 2,1-DCl and 1,1-HCl elimination reactions, respectively, which corresponds to branching fractions of 0.84 and 0.16. The experimental rate constants were compared to calculated statistical rate constants to assign threshold energies of 54 and ≈ 66 kcal mol-1 for the 1,2-DCl and 1,1-HCl reactions, respectively. The statistical rate constants were obtained from models developed from electronic-structure calculations for the molecule and its transition states. The rate constant (5.3 x 107 s-1) for the unimolecular decomposition of CHCl2CHCl2 molecules formed with 82 kcal mol-1 of vibrational energy by the recombination of CHCl2 radicals also is reported. Based upon the magnitude of the calculated rate constant, 1,1-HCl elimination must contribute less than 15% to the reaction; 1,2-HCl elimination is the major reaction and the threshold energy is 59 kcal mol-1. Calculations also were done to analyze previously published rate constants for chemically activated CD2Cl-CHCl2 molecules with 86 kcal mol-1 of energy in order to obtain a better overall description of the nature of the 1,1-HCl pathway for 1,1-dichloroalkanes. The interplay of the threshold energies for the 2,1-HCl and 1,1-HCl reactions and the available energy determines the product branching fractions for individual molecules. The unusual nature of the transition state for 1,1-HCl elimination is discussed.

The 1:1 adduct of caffeine and 2-(1,3-dioxoisoindolin-2-ylacetic acid

Directory of Open Access Journals (Sweden)

Moazzam H. Bhatti

2011-09-01

Full Text Available In the crystal structure of the title adduct [systematic name: 2-(1,3-dioxoisoindolin-2-ylacetic acid–1,3,7-trimethyl-1,2,3,6-tetrahydro-7H-purine-2,6-dione (1/1], C8H10N4O2·C10H7NO4, the components are linked by an O—H...N hydrogen-bond and no proton transfer occurs.

Synthesis of enantiomerically pure thiocrown ethers derived from 1,1'-binaphthalene-2,2'-diol

NARCIS (Netherlands)

Stock, H. Thijs; Kellogg, Richard M.

1996-01-01

Synthetic methodology is given for the preparation of two different types of thiocrown ethers from optically pure 1,1'-binaphthalene-2,2'-diol (10). The conceptually simplest approach starts from optically pure 10 itself, which is alkylated (4 equiv of K2CO3 in DMF at 110 degrees C) with

DB2 11 the ultimate database for cloud, analytics, and mobile

CERN Document Server

Campbell, John; Jones, Gareth; Parekh, Surekha; Yothers, Jay

2014-01-01

Building on the prior book ""DB2 11: The Database for Big Data and Analytics,"" published in 2013, this book is written particularly for new and existing DB2 for z/OS customers and users who want to learn as much as they can about the new software version before migrating their organizations to DB2 11 for z/OS. The book begins with a technical overview of DB2 11 features and explains how the new functions in DB2 11 can help enterprise customers address the challenges they face with the explosion of data and information. There has been rapid growth in the variety, volume, and velocity of dat

Atomic diffusion in laser surface modified AISI H13 steel

Science.gov (United States)

Aqida, S. N.; Brabazon, D.; Naher, S.

2013-07-01

This paper presents a laser surface modification process of AISI H13 steel using 0.09 and 0.4 mm of laser spot sizes with an aim to increase surface hardness and investigate elements diffusion in laser modified surface. A Rofin DC-015 diffusion-cooled CO2 slab laser was used to process AISI H13 steel samples. Samples of 10 mm diameter were sectioned to 100 mm length in order to process a predefined circumferential area. The parameters selected for examination were laser peak power, pulse repetition frequency (PRF), and overlap percentage. The hardness properties were tested at 981 mN force. Metallographic study and energy dispersive X-ray spectroscopy (EDXS) were performed to observe presence of elements and their distribution in the sample surface. Maximum hardness achieved in the modified surface was 1017 HV0.1. Change of elements composition in the modified layer region was detected in the laser modified samples. Diffusion possibly occurred for C, Cr, Cu, Ni, and S elements. The potential found for increase in surface hardness represents an important method to sustain tooling life. The EDXS findings signify understanding of processing parameters effect on the modified surface composition.

The structure at 1.7 Å resolution of the protein product of the At2g17340 gene from Arabidopsis thaliana

International Nuclear Information System (INIS)

Bitto, Eduard; Bingman, Craig A.; Allard, Simon T. M.; Wesenberg, Gary E.; Phillips, George N. Jr

2005-01-01

The crystal structure of the 40.8 kDa At2g17340 protein from A. thaliana was determined at 1.7 Å resolution. The structure provides the first insight into the structural organization of the Pfam01937.11 family and establishes that the proteins of this family coordinate a metal in its putative active site. The crystal structure of the At2g17340 protein from A. thaliana was determined by the multiple-wavelength anomalous diffraction method and was refined to an R factor of 16.9% (R free = 22.1%) at 1.7 Å resolution. At2g17340 is a member of the Pfam01937.11 protein family and its structure provides the first insight into the structural organization of this family. A number of fully and highly conserved residues defined by multiple sequence alignment of members of the Pfam01937.11 family were mapped onto the structure of At2g17340. The fully conserved residues are involved in the coordination of a metal ion and in the stabilization of loops surrounding the metal site. Several additional highly conserved residues also map into the vicinity of the metal-binding site, while others are clearly involved in stabilizing the hydrophobic core of the protein. The structure of At2g17340 represents a new fold in protein conformational space

17 CFR 403.2 - Hypothecation of customer securities.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Hypothecation of customer... UNDER SECTION 15C OF THE SECURITIES EXCHANGE ACT OF 1934 PROTECTION OF CUSTOMER SECURITIES AND BALANCES § 403.2 Hypothecation of customer securities. Every registered government securities broker or dealer...

Road Materials and Pavement Design volume 17(2)

CSIR Research Space (South Africa)

De Beer, Morris

2016-03-01

Full Text Available Materials and Pavement Design Volume 17, 2016 - Issue 2 Editorial Board Page ebi | Published online: 03 Oct 2016  http://dx.doi.org/10.1080/14680629.2016.1244475 Editors-in-Chief Hervé DI BENEDETTO - University of Lyon/ENTPE, Vaulx-en-Velin, France...

Effects of fresh gas flow, tidal volume, and charcoal filters on the washout of sevoflurane from the Datex Ohmeda (GE) Aisys, Aestiva/5, and Excel 210 SE Anesthesia Workstations.

Science.gov (United States)

Sabouri, A Sassan; Lerman, Jerrold; Heard, Christopher

2014-10-01

We investigated the effects of tidal volume (VT), fresh gas flow (FGF), and a charcoal filter in the inspiratory limb on the washout of sevoflurane from the following Datex Ohmeda (GE) Anesthesia Workstations (AWSs): Aisys, Aestiva/5, and Excel 210SE. After equilibrating the AWSs with 2% sevoflurane, the anesthetic was discontinued, and the absorbent anesthesia breathing circuit (ABC), reservoir bag, and test lung were changed. The lung was ventilated with 350 or 200 mL·breath(-1), 15 breaths·min(-1), and a FGF of 10 L·min(-1) while the washout of sevoflurane was performed in triplicate using a calibrated Datex Ohmeda Capnomac Ultima™ and a calibrated MIRAN SapphIRe XL ambient air analyzer until the concentration was ≤ 10 parts per million (ppm). The effects of decreasing the FGF to 5 and 2 L·min(-1) after the initial washout and of a charcoal filter in the ABC were recorded separately. The median washout times with the Aisys AWS (14 min, P Excel 210SE (32 min). The mean (95% confidence interval) washout time with the Aisys increased to 23.5 (21.5 to 25.5) min with VT 200 mL·breath(-1) (P < 0.01). Decreasing the FGF from 10 to 5 and 2 L·min(-1) with the Aisys caused a rebound in sevoflurane concentration to ≥ 50 ppm. Placement of a charcoal filter in the inspiratory limb reduced the sevoflurane concentration to < 2 ppm in the Aisys and Aestiva/5 AWSs within two minutes. The GE AWSs should be purged with large FGFs and VTs ~350 mL·breath(-1) for ~25 min to achieve 10 ppm sevoflurane. The FGF should be maintained to avoid a rebound in anesthetic concentration. Charcoal filters rapidly decrease the anesthetic concentration to < 2 ppm.

Trisomy 2q11.2-->q21.1 resulting from an unbalanced insertion in two generations.

Science.gov (United States)

Glass, I A; Stormer, P; Oei, P T; Hacking, E; Cotter, P D

1998-01-01

In this communication, we describe two cases of proximal 2q trisomy (2q11.2--> q21.1) resulting from an interchromosomal insertion. The chromosomal origin of the insertion was confirmed by fluorescence in situ hybridisation. An unbalanced karyotype, 46,XX,der(8) ,ins(8;2) (p21.3; q21.1q11.2), was found in the proband and her mother, who both have mild mental retardation, short stature, dysmorphic features, insulin dependent diabetes mellitus, and a psychotic illness. This family is a rare example of direct transmission of a partial autosomal trisomy. Images PMID:9598728

Physical and Tribological Properties of Nitrided AISI 316 Stainless Steel Balls

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Yang Shicai

2016-01-01

Full Text Available AISI 316 austenitic stainless steel balls (diameters 5.0 and 12.0 mm, typical hardness 250 HV0.3 and flat samples (20×20×2.0 mm were nitrided by a pulsed glow discharge Ar/N2 plasma. Hardness of the ball surfaces was analysed using Vickers indentation. Thermal stability of the nitrided balls (diameter 12.0 mm was studied using a furnace to heat them in air for 8 hours at temperatures up to 700.0°C and then, after cooling to room temperature, the surface hardness of the heated balls was re-measured. Scanning electron microscopy and X-ray diffraction were used to study the microstructures, composition and phase formation of the nitrided sublayers. Unlubricated pin-on-disc wear testing was used to evaluate the wear resistance of nitrided stainless steel balls (5.0 mm diameter and the results were compared with similar testing on hardened Cr-Steel balls (5 mm diameter with hardness of about 650 HV0.3. All the test results indicated that the nitrided AISI 316 austenitic stainless steel balls have advantages over the hardened Cr-Steel balls in terms of retaining high hardness after heat treatment and high resistance to sliding wear at room temperature under higher counterpart stress. These properties are expected to be beneficial for wide range of bearing applications.

Analysis of AISI 304 Tensile Strength as an Anchor Chain of Mooring System

Science.gov (United States)

Hamidah, I.; Wati, R.; Hamdani, R. A.

2018-05-01

The background of this research is the use of mild steel (i.e., St37) as anchor chain that works on the corrosive environment of seawater which is possible to decrease its tensile strength. The longer soaked in seawater, the more significant the lowering of its tensile strength. Anchor chain needs to be designed by considering its tensile strength and corrosion resistance, so it’s able to support mooring system well. The primary purpose of this research is obtaining the decreasing of stainless steel 304 (AISI 304) tensile strength which is corroded by seawater as anchor chain of the mooring system. It is also essential to obtain the lifetime of AISI304 and St37 as anchor chain with the same load, the corrosion rate of AISI 304, and St 37 in seawater. The method which was employed in this research is an experiment with four pieces of stainless steel AISI 304, and of St 37 corrosion testing samples, six pieces of stainless steel 304, and six pieces of St 37 for tensile testing samples. The result of this research shows that seawater caused stainless steel AISI 304 as anchor chain has decreased of tensile strength about 1.68 % during four weeks. Also, it indicates that AISI 304 as anchor chain has a lifetime about 130 times longer than St 37. Further, we found that the corrosion rate of stainless steel 304 in seawater is 0.2042 mpy in outstanding category, while the St 37 samples reached up to 27.0247 mpy ranked as fair category. This result recommends that AISI 304 more excellence than St 37 as anchor chain of the mooring system.

Mechanochemical synthesis of 1-stanna-2,3-dicarba-closo-dodecaborane SnB9C2H11

International Nuclear Information System (INIS)

Volkov, V.V.; Myakishev, K.G.; Solomatina, L.Ya.

1990-01-01

The possibility of synthesis of 1-stanna-2, 3-dicarba-dodecaborane (2), SnB 9 C 2 H 11 by the mechanical activation of solid mixtures of CsB 9 C 2 H 12 , NaH and SnCl 2 has been studied. These solid phase mechano-chemical reactions were performed in vacuum vibration mills without any liquid solvents at room temperature. Crystalline SnB 9 C 2 H 11 was produced by sublimation in vacuum at 140 deg C. Yioeld of the sublimate was 3-6%

17 CFR 240.15c1-2 - Fraud and misrepresentation.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Fraud and misrepresentation. 240.15c1-2 Section 240.15c1-2 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... Securities Exchange Act of 1934 Rules Relating to Over-The-Counter Markets § 240.15c1-2 Fraud and...

Study of the solidification of M2 high speed steel Laser Cladding coatings

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Candel, J. J.

2013-10-01

Full Text Available High speed steel laser cladding coatings are complex because cracks appear and the hardness is lower than expected. In this paper AISI M2 tool steel coatings on medium carbon AISI 1045 steel substrate have been manufactured and after Laser Cladding (LC processing it has been applied a tempering heat treatment to reduce the amount of retained austenite and to precipitate secondary carbides. The study of metallurgical transformations by Scanning Electron Microscopy (SEM and Electron Back Scattered Diffraction (EBSD shows that the microstructure is extremely fine and complex, with eutectic transformations and MC, M2C and M6C precipitation. Therefore, after the laser coating is necessary to use post-weld heat treatments.Los recubrimientos de acero rápido por Laser Cladding (LC son complejos porque aparecen fisuras y la dureza es menor a la esperada. En este trabajo se han fabricado recubrimientos de acero AISI M2 sobre acero al carbono AISI 1045 y tras el procesado por láser, se han revenido para reducir la cantidad de austenita retenida y precipitar carburos secundarios. El estudio de las transformaciones metalúrgicas con Microscopía Electrónica de Barrido (MEB y Difracción de Electrones Retrodispersados (EBSD muestra que la microestructura es extremadamente fina y compleja, presenta transformaciones eutécticas y precipitación de carburos MC, M2C y M6C. Por tanto, tras el recubrimiento por láser es necesario recurrir a tratamientos térmicos post-soldeo.

Synthesis and reactivity of single-phase Be{sub 17}Ti{sub 2} intermetallic compounds

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae-Hwan, E-mail: kim.jaehwan@jaea.go.jp [Breeding Functional Materials Development Group, Sector of Fusion Research and Development, Japan Atomic Energy Agency (Japan); Iwakiri, Hirotomo; Furugen, Tatsuaki [Faculty of Education Elementary and Secondary School Teacher Training Program, University of the Ryukyus, Okinawa (Japan); Nakamichi, Masaru [Breeding Functional Materials Development Group, Sector of Fusion Research and Development, Japan Atomic Energy Agency (Japan)

2016-01-15

Highlights: • Preliminary synthesis of single-phase Be{sub 17}Ti{sub 2} was succeeded. • Reactivity difference between beryllium and beryllides may be caused by a lattice strain. • Oxidation of Be{sub 17}Ti{sub 2} at high temperatures results in the formation of TiO{sub 2}. • Simulation results reveal that a stable site for hydrogen at the center of tetrahedron exists. - Abstract: To investigate feasibility for application of Be{sub 17}Ti{sub 2} as a neutron multiplier as well as a refractory material, single-phase Be{sub 17}Ti{sub 2} intermetallic compounds were synthesized using an annealing heat treatment of the starting powder and a plasma sintering method. Scanning electron microscopic observations and X-ray diffraction measurements reveal that the single-phase Be{sub 17}Ti{sub 2} compounds were successfully synthesized. We examined the reactivity of Be{sub 17}Ti{sub 2} with 1% H{sub 2}O and discovered that a larger stoichiometric amount of Ti resulted in the formation of TiO{sub 2} on the surface at high temperatures. This oxidation may also contribute to an increase in both weight gain and generation of H{sub 2}. This suggests that the formation of the Ti-depleted Be{sub 17}Ti{sub 2−x} layer as a result of oxidation facilitates an increased reactivity with H{sub 2}O. To evaluate the safety aspects of Be{sub 17}Ti{sub 2}, we also investigated the hydrogen positions and solution energies based on the first principle. The calculations reveal that there are 10 theoretical sites, where 9 of these sites have hydrogen solution energies with a positive value (endothermic) and 1 site located at the center of a tetrahedron comprising two Be and two Ti atoms gives a negative value (exothermic).

CYP2C19*2 and CYP2C19*17 variants and effect of tamoxifen on breast cancer recurrence

DEFF Research Database (Denmark)

Damkier, Per; Kjaersgaard, Anders; Barker, Kimberly A.

2017-01-01

*17 allele were 1.02 (CI 0.71-1.46) and 0.57 (CI 0.26-1.24), respectively. Accounting for CYP2D6 genotype status did not change these estimates. We found no evidence to support a clinically meaningful role of CYP2C19 polymorphisms and response to tamoxifen in breast cancer patients and, consequently, CYP2C19...... genotype status should not be included in clinical decisions on tamoxifen treatment....

Psychopathology and cognition in children with 22q11.2 deletion syndrome

Science.gov (United States)

Niarchou, Maria; Zammit, Stanley; van Goozen, Stephanie H. M.; Thapar, Anita; Tierling, Hayley M.; Owen, Michael J.; van den Bree, Marianne B. M.

2014-01-01

Background Children with 22q11.2 deletion syndrome (22q11.2DS) have been reported to have high rates of cognitive and psychiatric problems. Aims To establish the nature and prevalence of psychiatric disorder and neurocognitive impairment in children with 22q11.2DS and test whether risk of psychopathology is mediated by the children’s intellectual impairment. Method Neurocognition and psychopathology were assessed in 80 children with 22q11.2DS (mean age 10.2 years, s.d. = 2.1) and 39 sibling controls (mean age 10.9 years, s.d. = 2.0). Results More than half (54%) of children with 22q11.2DS met diagnostic criteria for one or more DSM-IV-TR psychiatric disorder. These children had lower IQ (mean 76.8, s.d. = 13.0) than controls (mean 108.6, s.d. = 15.2) (Ppsychopathology was not mediated by intellectual impairment. Conclusions 22q11.2DS is not related to a specific psychiatric phenotype in children. Moreover, the deletion has largely independent effects on IQ and risk of psychopathology, indicating that psychopathology in 22q11.2DS is not a non-specific consequence of generalised cognitive impairment. PMID:24115343

Tribological behavior of an austenitic stainless steel AISI 316L nitrurated by DC-pulsed plasma

International Nuclear Information System (INIS)

De Las Heras, E; Walther, F; Corengia, P.A; Quinteiro, M.O; Cabo, A; Bruhl, S; Sommadossi, S

2004-01-01

Austenitic stainless steels are widely used in different applications because they withstands corrosion. Ionic nitruration has proven to be an adequate technique for modifying this type of steel, in order to improve its resistance to wear without diminishing its resistance to corrosion. While many publications have reported improvements in the tribological properties of the nitrurated AISI 316, systematic studies that evaluate this behavior using industrial equipment for its thermochemical treatment are of interest. This work studied the tribological behavior of an AISI 316L steel nitrurated by DC pulsed plasma in an industrial machine in an atmosphere of 25% N 2 and 75% H 2 for 20 h at 400 o C by means of abrasion tests under different conditions in an A 135 Amsler-disk machine. In order to characterize the abraded samples microhardness, optic and scanning electron microscopy profiles to determine the abrasion mechanisms were performed. The results showed substantial improvement in the abrasion resistance of the nitrurated samples compared to the non nitrurated ones and the different abrasion mechanisms are discussed to explain the test results (CW)

Measurement of the in-pile core temperature of an EL-4 pencil element, first charge (can of type-347 stainless steel, 0.4 mm thick, UO{sub 2} fuel, 11 mm diameter). Determination of the apparent thermal conductivity integral of in-pile UO{sub 2}; Mesure de la temperature a coeur en pile d'un crayon EL-4 1er jeu (gaine acier inoxydable, nuance 347 - epaisseur 0,4 mm - combustible UO{sub 2} - diametre 11 mm). Determination de l'integrale de conductibilite thermique apparente de l'UO{sub 2} en pile

Energy Technology Data Exchange (ETDEWEB)

Lavaud, B; Ringot, C; Vignesoult, N [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

1966-11-01

'un element combustible EL-4, type premier jeu, a gaine en acier inoxydable. On mesure cette temperature au coeur du crayon en pile a l'aide d'un thermocouple pour haute temperature: tungstene-rhenium a gaine tantale. Le crayon est place dans des conditions de fonctionnement analogues a celles de EL-4, tant en ce qui concerne la puissance specifique et la temperature sur gaine que la pression externe sur la gaine. La puissance specifique est obtenue dans le reacteur EL-3 avec un enrichissement de l'UO{sub 2} legerement superieur a celui normalement prevu pour EL-4. La temperature de gaine et la pression visees sont realisees a l'aide d'un conteneur d'irradiation en zircaloy-2 et a remplissage NaK, adapte, aux conditions du reacteur EL-3. - Les temperatures de l'UO{sub 2} a coeur, et de la surface de la gaine etant mesurees; - La puissance etant calculee a partir des echanges thermiques dans le conteneur etalonne en laboratoire; - La chute de temperature au contact UO{sub 2}-gaine etant deduite de mesures faites en laboratoire dans des conditions de flux calorifique comparables et sous une atmosphere de gaz correspondant au debut de la vie de l'element combustible; on peut tracer la courbe integrale de conductibilite. Les examens micro-graphiques de la structure de l'oxyde permettent de verifier la repartition des temperatures dans l'oxyde, deduite de l'integrale de conductibilite thermique. (auteurs)

Reassessment of the swelling behavior of AISI 304 stainless steel

International Nuclear Information System (INIS)

Garner, F.A.; Porter, D.L.

1982-03-01

Published swelling data derived from EBR-II irradiations of AISI 304 and 304L have been reanalyzed in light of insights gained from irradiation of AISI 316 and Fe-15Cr-25Ni. The primary influence of temperature, displacement rate and compositional variations in the 300 series stainless steels lies in the duration of the transient regime of swelling and not in the steady-state or constant swelling rate regime

(2,3,7,8,12,13,17,18-Octaethylporphyrinato-κ4Ncobalt(II–2-nitrobenzaldehyde (1/2

Directory of Open Access Journals (Sweden)

Anissa Mansour

2012-09-01

Full Text Available The asymmetric unit of the title compound, [Co(C36H44N4]·2C7H5NO3, is composed of one half of the complex, arranged about an inversion center, and a complete 2-nitrobenzaldehyde (NBA molecule. The structure consists of columns that contain interleaved molecules of NBA and [CoII(OEP] (OEP is 2,3,7,8,12,13,17,18-octaethylporphyrin, which are stacked along the a axis. The CoII atom is involved in a π interaction with the ring of the NBA molecule with a centroid–metal distance of 3.508 (6 Å. There is an intramolecular C—H...O hydrogen bond in the NBA molecule.

Corrosion and microstructural analysis data for AISI 316L and AISI 347H stainless steels after exposure to a supercritical water environment

Directory of Open Access Journals (Sweden)

A. Ruiz

2016-06-01

Full Text Available This article presents corrosion data and microstructural analysis data of austenitic stainless steels AISI 316L and AISI 347H exposed to supercritical water (25 MPa, 550 °C with 2000 ppb of dissolved oxygen. The corrosion tests lasted a total of 1200 h but were interrupted at 600 h to allow measurements to be made. The microstructural data have been collected in the grain interior and at grain boundaries of the bulk of the materials and at the superficial oxide layer developed during the corrosion exposure.

Microstructure and tribology of ion-mixed Fe/Ti/C multilayers on AISI 304 stainless steel

International Nuclear Information System (INIS)

Nastasi, M.; Hirvonen, J.P.; Zocco, T.G.; Jervis, T.R.

1991-01-01

A multilayered Fe/Ti/C structure consisting of eleven alternating sublayers, four Fe, four Ti and three C, was ion mixed on an AISI 304 stainless steel substrate with 400 keV Xe 2+ . Complete mixing was observed after an irradiation of 1x10 17 Xe/cm 2 at 550degC. Electron diffraction revealed the formation of the compounds TiC and Fe 3 C and a small amount of an amorphous phase. Some samples were given a second irradiation with 5x10 15 Xe/cm 2 at 0degC. The phases present following the second irradiation were TiC, α-Fe and an amorphous phase. Tribological and nanoindentation measurements revealed that both types of samples possessed similar hardness and friction properties. The ion mixed samples possessed an increased hardness and a decreased friction coefficient relative to untreated polished stainless-steel substrate. However, the wear life of the hot ion mixed sample was consistently longer than the wear life of the sample processed at both 550 and 0degC. These results are explained by differences in adhesive wear which result from differences in the chemical reactivity of the phases formed during ion beam processing. (orig.)

Detection of the deletion on Yp11.2 in a Chinese population.

Science.gov (United States)

Chen, Wenjing; Wu, Weiwei; Cheng, Jianding; Zhang, Yinming; Chen, Yong; Sun, Hongyu

2014-01-01

Sex determination tests based on Amelogenin gene as part of commercial PCR multiplex reaction kits have been widely applied in forensic DNA analysis. Mutations that cause dropout of Y chromosomal Amelogenin gene (AMELY) could lead to errors in gender determination and mixture interpretation. To infer the mechanism and estimate the dropout frequency of AMELY and adjacent Y-STRs, we studied 3 samples with AMELY dropout combined with DYS458 and/or DYS456 and 37 samples with DYS456 dropout. DYS456, DYS458 and AMELY are located in the Yp11.2 region. The singleplex amplification system showed the null alleles could be caused by fragment deletion in Yp11.2 rather than a point mutation in the primer binding region. After detection of the 17 Y-STR and 77 STS markers, the deletion map showed different patterns. The DYS456-AMELY-DYS458 deletion pattern was the largest, breaking from 3.60 Mb to 8.29 Mb in the Y chromosome, and the overall frequency was 0.0077%. The AMELY-DYS458 deletion pattern was broke from 6.74 Mb to 9.17 Mb, with a 0.0155% frequency. The DYS456 negative pattern was concentrated in two main deletion regions, with a 0.8220% frequency. The frequency of all negative pattern was 0.0155%. All the AMELY-DYS458 and DYS456-AMELY-DYS458, and 92% of the DYS456 deletion patterns belonged to Hg O3, the rest belonged to Hg Q. The DYS456 deletion pattern was first reported in Chinese population. The current and previous findings suggest additional gender test for ambiguous sex determination may be required. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Magnetoelasticity of (Lu.sub.0.8./sub.Ce.sub.0.2./sub.).sub.2./sub.Fe.sub.17./sub. intermetallic compound

Czech Academy of Sciences Publication Activity Database

Andreev, Alexander V.; Koyama, K.; Tereshina, Evgeniya; Prokleška, J.; Watanabe, K.

2009-01-01

Roč. 477, 1-2 (2009), s. 62-67 ISSN 0925-8388 R&D Projects: GA ČR(CZ) GA202/06/0185 Institutional research plan: CEZ:AV0Z10100520 Keywords : R 2 T 17 * Lu 2 Fe 17 * ferromagnetism * metamagnetism * magnetostriction Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.135, year: 2009

Study on tempering behaviour of AISI 410 stainless steel

International Nuclear Information System (INIS)

Chakraborty, Gopa; Das, C.R.; Albert, S.K.; Bhaduri, A.K.; Thomas Paul, V.; Panneerselvam, G.; Dasgupta, Arup

2015-01-01

Martensitic stainless steels find extensive applications due to their optimum combination of strength, hardness and wear-resistance in tempered condition. However, this class of steels is susceptible to embrittlement during tempering if it is carried out in a specific temperature range resulting in significant reduction in toughness. Embrittlement of as-normalised AISI 410 martensitic stainless steel, subjected to tempering treatment in the temperature range of 673–923 K was studied using Charpy impact tests followed by metallurgical investigations using field emission scanning electron and transmission electron microscopes. Carbides precipitated during tempering were extracted by electrochemical dissolution of the matrix and identified by X-ray diffraction. Studies indicated that temper embrittlement is highest when the steel is tempered at 823 K. Mostly iron rich carbides are present in the steel subjected to tempering at low temperatures of around 723 K, whereas chromium rich carbides (M 23 C 6 ) dominate precipitation at high temperature tempering. The range 773–823 K is the transition temperature range for the precipitates, with both Fe 2 C and M 23 C 6 types of carbides coexisting in the material. The nucleation of Fe 2 C within the martensite lath, during low temperature tempering, has a definite role in the embrittlement of this steel. Embrittlement is not observed at high temperature tempering because of precipitation of M 23 C 6 carbides, instead of Fe 2 C, preferentially along the lath and prior austenite boundaries. Segregation of S and P, which is widely reported as one of the causes for temper embrittlement, could not be detected in the material even through Auger electron spectroscopy studies. - Highlights: • Tempering behaviour of AISI 410 steel is studied within 673–923 K temperature range. • Temperature regime of maximum embrittlement is identified as 773–848 K. • Results show that type of carbide precipitation varies with

Nitrosonium complexation by the tetraphosphonate cavitand 5,11,17,23-tetramethyl-6,10:12,16:18,22:24,4-tetrakis(phenylphosphonato-κ2O,Oresorcin(4arene

Directory of Open Access Journals (Sweden)

Roberta Pinalli

2017-12-01

Full Text Available The crystal structure of a new supramolecular complex between the tetraphosphonate cavitand 5,11,17,23-tetramethyl-6,10:12,16:18,22:24,4-tetrakis(phenylphosphonato-κ2O,O′resorcin(4arene and the nitrosyl cation NO+, as the BF4− salt, is reported. The complex, of general formula [(C56H44P4O12(NO]BF4·CH2Cl2 or NO@Tiiii[H, CH3, C6H5] BF4·CH2Cl2, crystallizes in the space group P-1. The nitrosyl cation is disordered over two equivalent positions, with occupancies of 0.503 (2 and 0.497 (2, and interacts with two adjacent P=O groups at the upper rim of the cavitand through dipole–charge interactions. In the lattice, the cavitands are connected through a series of C—H...π interactions involving the methyl and methylenic H atoms and the aromatic rings of the macrocycle. The structure is further stabilized by the presence of C—H...F interactions between the hydrogen atoms of the cavitands and the F atoms of the tetrafluoridoborate anion. As a result of the disorder, the lattice dichloromethane molecules could not be modelled in terms of atomic sites, and were treated using the PLATON SQUEEZE procedure [Spek (2015. Acta Cryst. C71, 9–18]. The complexation process has also been studied in solution through NMR titrations.

Synthesis and photoluminescence properties of Ba2CaZn2Si6O17:Eu3+ red phosphors for white LED applications

International Nuclear Information System (INIS)

Annadurai, G.; Kennedy, S. Masilla Moses

2016-01-01

Novel pellyite type Ba 2 CaZn 2 Si 6 O 17 :Eu 3+ red emitting phosphors with different Eu 3+ contents were synthesized by the solid state reaction method. The crystal structure, photoluminescence properties and concentration quenching of Ba 2 CaZn 2 Si 6 O 17 :Eu 3+ phosphors were investigated. Powder X-ray diffraction measurements confirmed the structure of the samples. The photoluminescence emission (PL) and excitation (PLE) spectra were measured. The results showed that the dominant hypersensitive red emission peak of the phosphors Ba 2 CaZn 2 Si 6 O 17 :Eu 3+ was located at 613 nm attributed to the Eu 3+ transition ( 5 D 0 → 7 F 2 ) which could be effectively excited by 395 nm (near-UV). The latter band matched well with the emission from the near-UV LED chips. The intensity ratio of 5 D 0 → 7 F 2 to 5 D 0 → 7 F 1 transition showed slight variation with Eu 3+ concentrations. The Eu 3+ emission intensity was maximum for 9 mol%. The luminescence quantum efficiency was determined and also the decay profiles were obtained and analyzed. In addition, the Commission International del'Eclairage (CIE) chromaticity coordinates of Ba 2 CaZn 2 Si 6 O 17 :0.09Eu 3+ phosphor were calculated to be 0.637 and 0.362. The experimental results demonstrated that the Ba 2 CaZn 2 Si 6 O 17 :Eu 3+ red emitting phosphor is a potential candidate for white light emitting diodes (WLEDs) pumped by near-UV chip. - Highlights: • A novel Ba 2 CaZn 2 Si 6 O 17 :Eu 3+ red phosphor was synthesized. • The samples yielded a dominant PL emission of Eu 3+ at 613 nm. • Eu 3+ concentration was optimized to be 9 mol% in Ba 2 CaZn 2 Si 6 O 17. • CIE chromaticity coordinates were estimated from the emission spectrum.

Influence of the surface finishing on the corrosion behaviour of AISI 316L stainless steel

Czech Academy of Sciences Publication Activity Database

Dundeková, S.; Zatkalíková, V.; Fintová, Stanislava; Hadzima, B.; Škorík, Viktor

2015-01-01

Roč. 22, č. 1 (2015), s. 48-53 ISSN 1335-0803 R&D Projects: GA MŠk(CZ) EE2.3.30.0063 Institutional support: RVO:68081723 Keywords : AISI 316L stainless steel * Corrosion * Immersion test * Corrosion rate Subject RIV: JK - Corrosion ; Surface Treatment of Materials http://ojs.mateng.sk/index.php/Mateng/article/view/166/251

Effects of nitrogen ion implantation time on tungsten films deposited by DC magnetron sputtering on AISI 410 martensitic stainless steel

Energy Technology Data Exchange (ETDEWEB)

Malau, Viktor, E-mail: malau@ugm.ac.id; Ilman, Mochammad Noer, E-mail: noer-ilman@yahoo.com; Iswanto, Priyo Tri, E-mail: priyatri@yahoo.com; Jatisukamto, Gaguk, E-mail: gagukjtsk@yahoo.co.id [Mechanical and Industrial Engineering Department, Gadjah Mada University Jl. Grafika 2, Yogyakarta, 55281 (Indonesia)

2016-03-29

Nitrogen ion implantation time on tungsten thin film deposited on surface of AISI 410 steel has been performed. Tungsten thin film produced by dc magnetron sputtering method was deposited on AISI 410 martensitic stainless steel substrates, and then the nitrogen ions were implanted on tungsten thin film. The objective of this research is to investigate the effects of implantation deposition time on surface roughness, microhardness, specific wear and corrosion rate of nitrogen implanted on tungsten film. Magnetron sputtering process was performed by using plasma gas of argon (Ar) to bombardier tungsten target (W) in a vacuum chamber with a pressure of 7.6 x 10{sup −2} torr, a voltage of 300 V, a sputter current of 80 mA for sputtered time of 10 minutes. Nitrogen implantation on tungsten film was done with an initial pressure of 3x10{sup −6} mbar, a fluence of 2 x 10{sup 17} ions/cm{sup 2}, an energy of 100 keV and implantation deposition times of 0, 20, 30 and 40 minutes. The surface roughness, microhardness, specific wear and corrosion rate of the films were evaluated by surfcorder test, Vickers microhardness test, wear test and potentiostat (galvanostat) test respectively. The results show that the nitrogen ions implanted deposition time on tungsten film can modify the surface roughness, microhardness, specific wear and corrosion rate. The minimum surface roughness, specific wear and corrosion rate can be obtained for implantation time of 20 minutes and the maximum microhardness of the film is 329 VHN (Vickers Hardness Number) for implantation time of 30 minutes. The specific wear and corrosion rate of the film depend directly on the surface roughness.

Structure and magnetic properties of Y2Fe17-xMnx compounds (x=0-6)

International Nuclear Information System (INIS)

Wang Yingang; Zhejiang Univ., Hangzhou; Yang Fuming; Chen Changpin; Tang Ning; Pan Hongge; Zhejiang Univ., Hangzhou; Wang Qidong

1996-01-01

The effect of Mn on structure and magnetic properties of Y 2 Fe 17-x Mn x compounds has been studied. Substitution of Mn for Fe does not change the structure of Y 2 Fe 17 , and all the Y 2 Fe 17-x Mn x compounds crystallize in Th 2 Ni 17 structure. The lattice constants first increase, then slightly decrease, and finally increase again. The Curie temperature of Y 2 Fe 17-x Mn x compounds first increases, shows a maximum at x=0.3, and then decreases again. The saturation magnetization of Y 2 Fe 17-x Mn x compounds decreases dramatically with increasing Mn content. The moments of Mn atoms in these compounds are also discussed. (orig.)

Developmental trajectories of fronto-executive functions in 22q11.2 deletion syndrome: A preliminary study

LENUS (Irish Health Repository)

Howley, S A

2011-01-01

22qll.2 deletion syndrome (22qllDS) is associated with borderline-mild intellectual disability and specific neurocognitive deficits, particularly in prefrontally-mediated executive functions (EF). There is evidence for white matter abnormalities in frontal cortical regions in 22qllDS, however little is known about the development of EF across the age range. Forty-eight individuals with 22qllDS were divided into 3 age groups: Child (7 male; n = 16; 6–11 years; M (SD) age = 8.4 (1.7); mean FSIQ = 72.9); Adolescent (7 male; n = 15; 12–15 years; M (SD) age = 13.1 (0.8); mean FSIQ = 68.0) and Adult (7 male; n = 17; 16–45 years; M (SD) age = 28.8 (11.5); mean FSIQ = 69.6). Forty healthy controls were also recruited and divided into the same 3 age groups: Child (6 male; 6–11 years, n = 12; M (SD) age = 9.3 (1.7); mean FSIQ = 99.1); Adolescent (6 male; 12–15 years; n = 12; M (SD) age = 13.2 (1.1); mean FSIQ = 100.9) and Adult (6 male; 16–45 years; n = 16; M (SD) age = 28.8 (9.4); mean FSIQ = 109). All participants completed standardised tests of a range of executive functions, specifically working memory, planning, problem-solving, strategy formation, cognitive flexibility and inhibition, and cross-sectional developmental trajectories of each function were constructed. No age-mediated improvements on EF tasks were observed in the 22qllDS groups, with the exception of verbal working memory. The control group exhibited significant age-mediated improvements in working memory, strategy formation and planning efficiency. These findings support the hypothesis that 22qllDS individuals experience atypical development of neuroanatomical regions and networks associated with EF in typical individuals. Future longitudinal work is required to examine intra-individual development of executive and non-executive cognitive processes.

Synthesis of carbon-11 labeled 1-(3,4-dimethoxybenzyl)-2,2-dimethyl-1,2,3,4-tetrahydroisoquinolinium derivatives as new potential PET SKCa channel imaging agents.

Science.gov (United States)

Gao, Mingzhang; Wang, Min; Zheng, Qi-Huang

2008-02-01

Small conductance Ca2+-activated K+ (SKCa) channels play an important role in many functions such as neuronal communication and behavioral plasticity, secretion, and cell proliferation. SKCa channel modulation is associated with various brain, heart, and cancer diseases. N-methyl-laudanosine and its structurally related derivatives, substituted 1-(3,4-dimethoxybenzyl)-2,2-dimethyl-1,2,3,4-tetrahydroisoquinoliniums, are reversible and selective SKCa channel blockers. Carbon-11 labeled N-methyl-laudanosine and its tetrahydroisoquinolinium derivatives may serve as new probes for positron emission tomography (PET) to image SKCa channels in the brain, heart, and cancer. The key intermediates, substituted isoquinolines (3a-c), were synthesized using a modification of the Pomeranz-Fritsch procedure. The precursors, substituted 1-(3,4-dimethoxybenzyl)-2-methyl-1,2,3,4-tetrahydroisoquinolines (8a-c), and their corresponding reference standards, substituted 1-(3,4-dimethoxybenzyl)-2,2-dimethyl-1,2,3,4-tetrahydroisoquinoliniums (9a-c), were synthesized from compounds 3a-c with 3,4-dimethoxybenzyl chloride (2) in multiple steps with moderate to excellent chemical yields. The precursor 6,7-dimethoxy-1-(3,4-dimethoxybenzyl)-2-methyl-1,2,3,4-tetrahydroisoquinoline (10) was commercially available, and the methylation of compound 10 with methyl iodide provided N-methyl-laudanosine (11). The target quaternary ammonium tracers, carbon-11 labeled 1-(3,4-dimethoxybenzyl)-2,2-dimethyl-1,2,3,4-tetrahydroisoquinoliniums ([11C]9a-c and [11C]11), were prepared by N-[11C]methylation of the tertiary amine precursors (8a-c and 10) with [11C]methyl triflate and isolated by a simplified solid-phase extraction (SPE) purification using a SiO2 or cation-exchange CM Sep-Pak cartridge in 40-65% radiochemical yields.

Wear behavior of the surface alloyed AISI 1020 steel with Fe-Nb-B by TIG welding technique

Energy Technology Data Exchange (ETDEWEB)

Kilinc, B., E-mail: bkilinc@sakarya.edu.tr; Durmaz, M.; Abakay, E. [Department of Metallurgical and Materials Engineering, Institute of Arts and Sciences, SakaryaUniversity, Esentepe Campus, 54187Sakarya (Turkey); Sen, U.; Sen, S. [Department of Metallurgical and Materials Engineering, Engineering Faculty, Sakarya University, Esentepe Campus, 54187 Sakarya (Turkey)

2015-03-30

Weld overlay coatings also known as hardfacing is a method which involves melting of the alloys and solidification for applied coatings. Recently hardfacing by welding has become a commonly used technique for improvement of material performance in extreme (high temperature, impact/abrasion, erosion, etc.) conditions.In the present study, the coatings were produced from a mixture of ferrous niobium, ferrous boron and iron powders in the ranges of -45µm particle size with different ratio. Fe{sub 12}Nb{sub 5}B{sub 3} and Fe{sub 2}NbBalloys were coated on the AISI 1020 steel surface by TIG welding. The phases formed in the coated layer are Fe{sub 2}B, NbB{sub 2}, NbFeB and Fe0,2 Nb{sub 0,8} phases. The hardness of the presence phases are changing between 1689±85 HV{sub 0.01}, and 181±7 HV{sub 0.1}. Microstructural examinations were realized by optical and scanning electron microscopy. The wear and friction behaviors of Fe{sub 12}Nb{sub 5}B{sub 3} and Fe2NbB realized on the AISI 1020 steel were investigated by the technique of TIG welding by using ball-on-disk arrangement against alumina ball.

Modelling of three-dimensional structures of cytochromes P450 11B1 and 11B2.

Science.gov (United States)

Belkina, N V; Lisurek, M; Ivanov, A S; Bernhardt, R

2001-12-15

The final steps of the biosynthesis of glucocorticoids and mineralocorticoids in the adrenal cortex require the action of two different cytochromes P450--CYP11B1 and CYP11B2. Homology modelling of the three-dimensional structures of these cytochromes was performed based on crystallographic coordinates of two bacterial P450s, CYP102 (P450BM-3) and CYP108 (P450terp). Principal attention was given to the modelling of the active sites and a comparison of the active site structures of CYP11B1 and CYP11B2 was performed. It can be demonstrated that key residue contacts within the active site appear to depend on the orientation of the heme. The obtained 3D structures of CYP11B1 and CYP11B2 were used for investigation of structure-function relationships of these enzymes. Previously obtained results on naturally occurring mutants and on mutants obtained by site-directed mutagenesis are discussed.

SPITZER OBSERVATIONS OF GX17+2: CONFIRMATION OF A PERIODIC SYNCHROTRON SOURCE

International Nuclear Information System (INIS)

Harrison, Thomas E.; McNamara, Bernard J.; Bornak, Jillian; Gelino, Dawn M.; Wachter, Stefanie; Rupen, Michael P.; Gelino, Christopher R.

2011-01-01

GX17+2 is a low-mass X-ray binary (LMXB) that is also a member of a small family of LMXBs known as 'Z-sources' that are believed to have persistent X-ray luminosities that are very close to the Eddington limit. GX17+2 is highly variable at both radio and X-ray frequencies, a feature common to Z-sources. What sets GX17+2 apart is its dramatic variability in the near-infrared, where it changes by ΔK ∼ 3 mag. Previous investigations have shown that these brightenings are periodic, recurring every 3.01 days. Given its high extinction (A V ≥ 9 mag), it has not been possible to ascertain the nature of these events with ground-based observations. We report mid-infrared Spitzer observations of GX17+2 which indicate a synchrotron spectrum for the infrared brightenings. In addition, GX17+2 is highly variable in the mid-infrared during these events. The combination of the large-scale outbursts, the presence of a synchrotron spectrum, and the dramatic variability in the mid-infrared suggest that the infrared brightening events are due to the periodic transit of a synchrotron jet across our line of sight. An analysis of both new, and archival, infrared observations has led us to revise the period for these events to 3.0367 days. We also present new Rossi X-Ray Timing Explorer (RXTE) data for GX17+2 obtained during two predicted infrared brightening events. Analysis of these new data, and data from the RXTE archive, indicates that there is no correlation between the X-ray behavior of this source and the observed infrared brightenings. We examine various scenarios that might produce periodic jet emission.

Determination of Proper Austenitization Temperatures for Hot Stamping of AISI 4140 Steel

Science.gov (United States)

Samadian, Pedram; Parsa, Mohammad Habibi; Shakeri, Amid

2014-04-01

High strength steels are desirable materials for use in automobile bodies in order to reduce vehicle weight and increase the safety of car passengers, but steel grades with high strength commonly show poor formability. Recently, steels with controlled microstructures and compositions are used to gain adequate strength after hot stamping while maintaining good formability during processing. In this study, microstructure evolutions and changes in mechanical properties of AISI 4140 steel sheets resulting from the hot stamping process at different austenitization temperatures were investigated. To determine the proper austenitization temperatures, the results were compared with those of the cold-worked and cold-worked plus quench-tempered specimens. Comparisons showed that the austenitization temperatures of 1000 and 1100 °C are proper for hot stamping of 3-mm-thick AISI 4140 steel sheets due to the resultant martensitic microstructure which led to the yield and ultimate tensile strength of 1.3 and 2.1 GPa, respectively. Such conditions resulted in more favorable simultaneous strength and elongation than those of hot-stamped conventional boron steels.

2-[2-Chloro-5-(trifluoromethylphenyl]hexahydropyrimidine monohydrate

Directory of Open Access Journals (Sweden)

Reza Kia

2008-09-01

Full Text Available The molecule of the title compound, C11H12ClF3N2·H2O, is a substituted hexahydropyrimidine. There are two crystallographically independent molecules (A and B and two water molecules in the asymmetric unit of the title compound. Intermolecular C—H...Cl (× 2, C—H...F, and C—H...N (× 2 hydrogen bonds generate S(5 ring motifs. The dihedral angle between the two benzene rings is 8.17 (11°. The F atoms in molecule B are disordered over four positions with refined site-occupancies of ca 0.35/0.19/0.29/0.17 for the four components. In the crystal structure, molecules are arranged into one-dimensional extended chains along the c axis and are further stacked along the a axis by directed four-membered O—H...O—H interactions, forming two-dimensional networks parallel to the ac plane. The short distances between the centroids of the benzene rings (3.8002–3.8327 Å indicate the existence of π–π interactions. In addition, the crystal structure is further stabilized by N—H...O, O—H...N (× 4, N—H...Cl and C—H...O (× 2 hydrogen-bonding interactions.

Childhood cognitive development in 22q11.2 deletion syndrome: case-control study.

Science.gov (United States)

Chawner, Samuel J R A; Doherty, Joanne L; Moss, Hayley; Niarchou, Maria; Walters, James T R; Owen, Michael J; van den Bree, Marianne B M

2017-10-01

Background 22q11.2 deletion syndrome (22q11.2DS) is associated with a high risk of childhood as well as adult psychiatric disorders, in particular schizophrenia. Childhood cognitive deterioration in 22q11.2DS has previously been reported, but only in studies lacking a control sample. Aims To compare cognitive trajectories in children with 22q11.2DS and unaffected control siblings. Method A longitudinal study of neurocognitive functioning (IQ, executive function, processing speed and attention) was conducted in children with 22q11.2DS ( n = 75, mean age time 1 ( T 1 ) 9.9, time 2 ( T 2 ) 12.5) and control siblings ( n = 33, mean age T 1 10.6, T 2 13.4). Results Children with 22q11.2DS exhibited deficits in all cognitive domains. However, mean scores did not indicate deterioration. When individual trajectories were examined, some participants showed significant decline over time, but the prevalence was similar for 22q11.2DS and control siblings. Findings are more likely to reflect normal developmental fluctuation than a 22q11.2DS-specific abnormality. Conclusions Childhood cognitive deterioration is not associated with 22q11.2DS. Contrary to previous suggestions, we believe it is premature to recommend repeated monitoring of cognitive function for identifying individual children with 22q11.2DS at high risk of developing schizophrenia. © The Royal College of Psychiatrists 2017.

Interactions Between Fibroblast Cells and Laser Beam Welded AISI 2205 Duplex Stainless Steel

Directory of Open Access Journals (Sweden)

Ceyhun KÖSE

2018-05-01

Full Text Available Because of their high mechanical strength, excellent corrosion resistance and good weldability, duplex stainless steels are mostly used in industries such as oil, chemistry, petrochemistry, food and occasionally used in medical industry. These properties have enabled us to use duplex stainless steels in biomedical applications recently. Accordingly, duplex stainless steel material can be highly important to examine the toxic effect on the cells. In this study, the effect of the AISI 2205 duplex stainless steels which are joined by CO2 laser beam welding on viability of L929 fibroblast cells has been studied in vitro for the first time. For this aim, the cells were kept in DMEM/F-12 (Thermofisher Scientific 31331-028 medium for 7 days. The viability study was experimentally studied using the MTT (Thiazolyl Blue Tetrazolium Bromide method for 7 days. The cell viability of the laser beam welded sample has been detected to be higher than that of the base metal and the control based on 7th day data. According to the obtained results, it was revealed that laser beam welded and base metal AISI 2205 duplex stainless steel has been found suitable to study for biomedical applications. DOI: http://dx.doi.org/10.5755/j01.ms.24.2.18006

Synthesis and in vivo evaluation of [O-methyl-11C](2R,4R)-4-hydroxy-2-[2-[2-[2-(3-methoxy)phenyl]ethyl]phenoxy] ethyl-1-methylpyrrolidine as a 5-HT2A receptor PET ligand

International Nuclear Information System (INIS)

Kumar, J.S. Dileep; Prabhakaran, Jaya; Erlandsson, Kjell; Majo, Vattoly J.; Simpson, Norman R.; Pratap, Mali; Heertum, Ronald L. van; Mann, J. John; Parsey, Ramin V.

2006-01-01

The serotonin 2A (5-HT 2A ) receptor is implicated in the pathophysiology of schizophrenia and mood disorders, and in vivo studies of this receptor would be of value in studying the pathophysiology of these disorders and in measuring the relationship of clinical response to receptor occupancy for 5-HT 2A antagonists such as atypical antipsychotics. Therefore, (2R,4R)-4-hydroxy-2-[2-[2-[2-(3-methoxy)-phenyl]ethyl] phenoxy]ethyl-1-methylpyrrolidine (MPM) (13), a selective and high-affinity (K i =0.79 nM) 5HT 2A antagonist, has been radiolabeled with carbon-11 by O-methylation of the corresponding desmethyl analogue (2R,4R)-4-hydroxy-2-[2-[2-[2-(3-hydroxy)phenyl]ethyl]phenoxy] ethyl-1-methylpyrrolidine (12) with [ 11 C]methyltriflate in order to determine the suitability of [ 11 C]MPM to quantify 5-HT 2A in living brain using PET. Desmethyl-MPM 12 and standard MPM were prepared, starting from 3-hydroxymethylphenol (2), in excellent yield. The yield obtained for radiolabeling was 40±5% (EOB), and the total synthesis time was 30 min at EOS. PET studies with [ 11 C]MPM in baboon showed a distribution in the brain consistent with the known distribution of 5-HT 2A receptors. The time-activity curves for the high-binding regions peaked at ∼45 min after injection. Blocking studies with M100907 demonstrated not only 38-57% blocking of tracer binding in brain regions known to have 5-HT 2A receptors but also 38% blocking in cerebellum, which has a low 5-HT 2A receptor concentration. Although [ 11 C]MPM exhibits appropriate kinetics in baboon for imaging 5-HT 2A receptors, its specific binding in cerebellum and higher proportion of nonspecific binding limit its usefulness for the in vivo quantification of 5-HT 2A receptors with PET

Effects of Nitrogen on the DOS and the Passive Film Breakdown Potential of AISI 304 Stainless Steel

International Nuclear Information System (INIS)

Choe, Han Cheol; Kim, Kwan Hyu; Kim, Myung Soo; Lee, Ho Jong

1992-01-01

Effects of nitrogen on the degree of sensitization (DOS) and the passive film breakdown potential (Eb) of AISI 304 stainless steel were studied by potentiostat. AISI 304 stainless steel samples containing 0.02 ∼ 0.10wt% nitrogen were sensitized by heat treatment at 650 .deg. C. The DOS was measured using the double-loop reactivation method of the electrochemical potentiodynamic reactivation (EPR) test with the potential scan rate of 150 mV/min in the electrolyte of 0.5 M H 2 SO 4 + 0.01 M KSCN solution at 25 .deg. C. The passive film breakdown potential (Eb) and repassivation potential (Er) were detected by using the cyclic potentiodynamic polarization test (CPPT) in 0.5M HCI solution at 25 .deg. C. In addition, corrosion morphologies were observed by SEM and optical microscope. It was found that nitrogen additions up to 0.1wt% decreased DOS and increased Eb and Er of AISI 304 stainless steel, whereas the increasing sensitization time increased the DOS and decreased Eb and Er. The corrosion morphologies showed severe pits and intergranular attacks in the samples of low nitrogen content and high DOS

Oxidación cíclica de un acero refractario AISI 310 a alta temperatura en atmósferas con contenidos de oxígeno variables

Directory of Open Access Journals (Sweden)

Higuera-Hidalgo, V.

2005-06-01

Full Text Available High temperature oxidation tests of an AISI 310 stainless steel was performed in two different environments: in an standard atmosphere (21 % oxygen at 704, 800, 884 and 1,000 °C and in the typical environment of a gas turbine and vapor generator of a combined-cycle electric generation unit (10 % oxygen at 800 and 1,000 °C. The oxidation kinetics was determined by means of the measurement of the weight gain per unit surface of the specimen and also determining the thickness of the oxide layer. Comparable results have been obtained using both methodologies and the effect of the oxygen content along with the other experimental differences were determined observing the oxidation kinetics in both environments. The cyclic oxidation of AISI 310 deteriorates at temperatures higher than 1,000 °C.

Se ha llevado a cabo un estudio experimental sobre la oxidación a altas temperaturas de un acero inoxidable refractario AISI 310, en dos ambientes diferentes: en una atmósfera convencional (21 % de O₂, a 704, 800, 884 y 1.000 °C y en un ambiente simulativo de una turbina de gas y del generador de vapor de uña central eléctrica de ciclo combinado (10-11 % de O₂, a 800 y 1.000 °C. La cinética de la oxidación del material se ha determinado a partir, tanto de la ganancia de peso por unidad de superficie experimentada por las probetas objeto de ensayo como por la determinación de los espesores de las capas de óxido formados. Se han obtenido resultados comparables con ambas metodologías y se ha puesto de manifiesto el efecto del contenido de oxígeno y de las demás diferencias experimentales a partir de la comparación de las cinéticas de oxidación del acero en los dos medios oxidantes analizados. La oxidación del acero AISI 310 en situaciones térmicas cíclicas empieza ya a ser importante a partir de una temperatura de 1.000 °C.

Effect of Pr6O11 doping in electrical and microstructural properties of SnO2-based varistors

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Hervê Stangler Irion

2014-04-01

Full Text Available The influence of the dopant Pr6O11 was investigated with regard to the electrical and microstructural properties of the system (98.95-x%SnO2.1.0%CoO.0.05%Ta2O5.x%Pr6O11, where x = 0.05%, 0.10%, 0.30% and 0.50% in mol. Pr6O11 doping modifies the electrical behavior of the ceramics. The electrical parameters were: α = 8.0, EB = 319 V cm-1 and Vb = 0.66 V barrier-1 for the system without Pr6O11 and α = 17.0, EB = 853 V cm-1 and Vb = 1.15 V barrier-1 with the addition of 0.10% in mol Pr6O11. The system with 0.05% in mol Pr6O11 had the same non-linearity coefficient α as the system with 0.10% in mol. However, breakdown electrical field and voltage per barrier rates were lower (EB = 708 V cm-1 and Vb = 0.98 V barrier-1. The low rates in the breakdown electrical field enabled the varistor systems under study to be used in protection systems for low-voltage energy grids. In the case of Pr6O11 concentrations above 0.10% in mol, the presence of the dopant became deleterious to the varistor’s electrical characteristics. This effect was due to an increase in praseodymium stannate (Pr2Sn2O7 secondary phase. The crystalline phase coupled to the cassiterite (SnO2 phase was found with XRD and SEM/EDS and quantified by Rietveld’s refining method.

Synthesis and H-1 NMR structural analysis of 11-aryl/heteroarylnaphtha[2,1-b]furans : X-ray crystal structure of 11-(4 '-pyridyl)naphtho[2,1-b]furan

NARCIS (Netherlands)

Mashraqui, S.H.; Patil, M.B.; Sangvikar, Y.; Ashraf, M.; Mistry, H.D.; Daub, E.T.H.; Meetsma, A.

2005-01-01

Synthesis of biaryl type systems, 11-aryl/heteroarylnaphtho[2,1-b]furans 8-11 has been described with a view to studying the conformational orientation of C-11 aryl/heteroaryl groups. Synthesis of 8-11 was accomplished by a two-step sequence involving O-alkylation of 2-naphthol with appropriate

Investigations of neutron-rich nuclei at the dripline through their analogue states : The cases of $^{10}$Li - $^{10}$Be (T=2) and $^{17}$C - $^{17}$N (T=5/2)

CERN Multimedia

2002-01-01

We propose to study the elastic resonance scattering reactions $^{9}$Li+p and $^{16}$C+p to investigate the energies, spins and parities of the lowest T=2 states in $^{10}$Be and the T=5/2 states in $^{17}$N. These are analogue states of the ground states and first excited states in $^{10}$Li and $^{17}$C.

Welding of High-Strength Steels for Aircraft and Missile Applications

Science.gov (United States)

1959-10-12

the aircraft industry for years. The alloys that have been most widely used have been AISI 4130, 4140 , and 4340. However, only the AISI 4340 steel...MARTENSITIC STEELS ................. . .. . . . 6 AISI 4340 and AMS 6434 ..................... ....................... 7 Welding Procedures...metal. A survey of the procedures currently being used is presented. Low-Alloy Martensitic Steels AISI 4340, AMS 6434, XZOO, 300M, and 17-Z2AS all are

The purification step is not crucial in EIA measurements of thromboxane B2 and 11-dehydrothromboxane B2 in human plasma.

Science.gov (United States)

Sadilkova, Lenka; Paluch, Zoltan; Mottlova, Jirina; Bednar, Frantisek; Alusik, Stefan

2012-01-01

Thromboxane B2 (TxB2) and particularly 11-dehydrothromboxane B2 (11-dTxB2) are widely used as prognostic risk markers of platelet activation in cardiovascular diseases. The main errors in TxB2 and 11-dTxB2 determination include either low concentrations of circulating TxB2 (1 - 2 pg/mL) and 11-dTxB2 (0.9 - 4.3 pg/mL) or rather high transiency (mean TxB2 half-life is approximately 5 minutes) as well as an incorrect pre-analytical phase set up. The aim of this study was to investigate the impact of a widely used purification step on the results of enzyme immunosorbent assay (EIA)--based measurement of the two selected thromboxanes. For the purpose of this study, 20 plasma samples (10 healthy donors, 10 patients under treatment with acetylsalicylic acid) were screened for TxB2 and 11-dTxB2 concentrations using commercial competitive EIA kits (Cayman Chemicals, Tallinn, Estonia; Neogen, Lexington, KY, USA) with or without the introduction of the purification procedure. The purification step does not significantly affect the results of EIA measurements of the two of TxA2 metabolites (TxB2, 11-dTxB2) in human plasma. The levels of TxB2 and 11-dTxB2 determined in the plasma samples were not significantly changed (p < 0.05) when the purification step was omitted compared to the purified samples. This study establishes a protocol allowing for reliable and reproducible plasma TxB2 and 11-dTxB2 EIA measurement for routine basic screening of platelet function.

Impact of structure and morphology of nanostructured ceria coating on AISI 304 oxidation kinetics

International Nuclear Information System (INIS)

Aadhavan, R.; Suresh Babu, K.

2017-01-01

Highlights: • Ceria coating reduced the oxidation kinetics of AISI304 by 3–4 orders. • Lower deposition rate (0.1 Å/s) resulted in dense and uniform coating. • Substrate temperature of 100 °C provided coating with smaller crystallite size. • Surface morphology of the coating has strong influence in oxidation protection. - Abstract: Nanostructured ceria-based coatings are shown to be protective against high-temperature oxidation of AISI 304 due to the dynamics of oxidation state and associated defects. However, the processing parameters of deposition have a strong influence in determining the structural and morphological aspects of ceria. The present work focuses on the effect of variation in substrate temperature (50–300 °C) and deposition rate (0.1–50 Å/s) of ceria in electron beam physical vapour evaporation method and correlates the changes in structure and morphology to high-temperature oxidation protection. Unlike deposition rate, substrate temperature exhibited a profound influence on crystallite size (7–18 nm) and oxygen vacancy concentration. Upon isothermal oxidation at 1243 K for 24 h, bare AISI 304 exhibited a linear mass gain with a rate constant of 3.0 ± 0.03 × 10"−"3 kg"2 m"−"4 s"−"1 while ceria coating lowered the kinetics by 3–4 orders. Though the thickness of the coating was kept constant at 2 μm, higher deposition rate offered one order lower protection due to the porous nature of the coating. Variation in the substrate temperature modulated the porosity as well as oxygen vacancy concentration and displayed the best protection for coatings deposited at moderate substrate temperature. The present work demonstrates the significance of selecting appropriate processing parameters to obtain the required morphology for efficient high-temperature oxidation protection.

Impact of structure and morphology of nanostructured ceria coating on AISI 304 oxidation kinetics

Energy Technology Data Exchange (ETDEWEB)

Aadhavan, R.; Suresh Babu, K., E-mail: sureshbabu.nst@pondiuni.edu.in

2017-07-31

Highlights: • Ceria coating reduced the oxidation kinetics of AISI304 by 3–4 orders. • Lower deposition rate (0.1 Å/s) resulted in dense and uniform coating. • Substrate temperature of 100 °C provided coating with smaller crystallite size. • Surface morphology of the coating has strong influence in oxidation protection. - Abstract: Nanostructured ceria-based coatings are shown to be protective against high-temperature oxidation of AISI 304 due to the dynamics of oxidation state and associated defects. However, the processing parameters of deposition have a strong influence in determining the structural and morphological aspects of ceria. The present work focuses on the effect of variation in substrate temperature (50–300 °C) and deposition rate (0.1–50 Å/s) of ceria in electron beam physical vapour evaporation method and correlates the changes in structure and morphology to high-temperature oxidation protection. Unlike deposition rate, substrate temperature exhibited a profound influence on crystallite size (7–18 nm) and oxygen vacancy concentration. Upon isothermal oxidation at 1243 K for 24 h, bare AISI 304 exhibited a linear mass gain with a rate constant of 3.0 ± 0.03 × 10{sup −3} kg{sup 2} m{sup −4} s{sup −1} while ceria coating lowered the kinetics by 3–4 orders. Though the thickness of the coating was kept constant at 2 μm, higher deposition rate offered one order lower protection due to the porous nature of the coating. Variation in the substrate temperature modulated the porosity as well as oxygen vacancy concentration and displayed the best protection for coatings deposited at moderate substrate temperature. The present work demonstrates the significance of selecting appropriate processing parameters to obtain the required morphology for efficient high-temperature oxidation protection.

Simulasi Kinerja Jaringan Nirkabel IEEE-802.11a dan IEEE-802.11g Menggunakan NS-2