{sup 99m}Tc-N.T.P. 15-5 imaging for the early and specific diagnosis of chondrosarcoma: proof of concept in rats

Energy Technology Data Exchange (ETDEWEB)

Miot-Noirault, E.; Vidal, A.; Rapp, M.; Madelmont, J.C.; Maublant, J.; Moins, N. [Institut National de la Sante et de la Recherche Medicale (INSERM), UMR 484, 63 - Clermont Ferrand (France); Redini, F.; Gouin, F.; Heymann, D. [Institut National de la Sante et de la Recherche Medicale (INSERM), ERI 7, EA 3822, 44 - Nantes (France)

2008-02-15

Aim. - The U.M.R. 484 I.N.S.E.R.M. develops a 'cartilage imaging strategy' with the {sup 99m}Tc-N.T.P. 15-5 tracer that selectively binds to cartilage proteoglycans, allowing a highly specific cartilage imaging. Since chondro-genic tumours are characterized by the presence of cartilaginous matrix, we hypothesized that the {sup 99m}Tc-N.T.P. 15-5 tracer would allow chondrosarcoma imaging, which is currently lacking in clinics. In the rat model of grade II para-tibial chondrosarcoma, we evaluated the relevance of {sup 99m}Tc-N.T.P. 15-5 imaging for an early and specific diagnosis of chondrosarcoma. Methods. - {sup 99m}Tc-N.T.P. 15-5 longitudinal imaging of animals was performed during two months after para-tibial ortho-topic tumour implantation in the right paw, the left being used as control. At regular intervals, animals were submitted to {sup 99m}Tc-M.D.P. bone imaging, the only examination used for SPECT diagnosis of chondrosarcoma in patients. Tumour volume was monitored for two months when the tumours became palpable, with the two perpendicular diameters measured. For both cartilage and bone imaging, the scans were considered positive when areas of tracer uptake were present at sites consistent with the sites of inoculation. For each animal, positive scans were analyzed at each stage using the semiquantitative method of the target to background ratio (T.B.R.), with the target R.O.I. being delineated over the tumour and background R.O.I. over vertebra and muscle. T.B.R. time-course was followed as a function of tumour growth.At study ending, each animal was sacrificed for histopathological control. Results. - {sup 99m}Tc-N.T.P. 15-5 scans were positive in 100% of the animals at very early stage (three days) after implantation, while no palpable nor measurable tumour could be assessed. Quantitative analysis of {sup 99m}Tc-N.T.P. 15-5 scans evidenced a significant uptake of the tracer at the implantation site at early stage. The time-course of T

Wurtzite BAlN and BGaN alloys for heterointerface polarization engineering

KAUST Repository

Liu, Kaikai

2017-11-30

The spontaneous polarization (SP) and piezoelectric (PZ) constants of BxAl1-xN and BxGa1-xN (0 ≤ x ≤ 1) ternary alloys were calculated with the hexagonal structure as reference. The SP constants show moderate nonlinearity due to the volume deformation and the dipole moment difference between the hexagonal and wurtzite structures. The PZ constants exhibit significant bowing because of the large lattice difference between binary alloys. Furthermore, the PZ constants of BxAl1-xN and BxGa1-xN become zero at boron compositions of ∼87% and ∼74%, respectively, indicating non-piezoelectricity. The large range of SP and PZ constants of BxAl1-xN (BAlN) and BxGa1-xN (BGaN) can be beneficial for the compound semiconductor device development. For instance, zero heterointerface polarization ΔP can be formed for BAlN and BGaN based heterojunctions with proper B compositions, potentially eliminating the quantum-confined Stark effect for c-plane optical devices and thus removing the need of non-polar layers and substrates. Besides, large heterointerface polarization ΔP is available that is desirable for electronic devices.

Thermal creep behavior of N36 zirconium alloy cladding tube

International Nuclear Information System (INIS)

Wang, P.; Zhao, W.; Dai, X.

2015-01-01

N36 is an alloy containing Zr, Sn, Nb and Fe that is developed by China as a superior cladding material to meet the performance of PWR fuel assembly at the maximum fuel rod burn-up. The creep characteristics of N36 zirconium alloy cladding tube were investigated at temperature from 593 K to 723 K with stress ranging from 20 MPa to 160 MPa. Transitions in creep mechanisms were noted, showing the distinct three rate-controlled creep mechanisms for the alloy at test conditions. In the region of low stresses with stress exponent n ∼ 1 and activation energy Q ∼ (104±4) kJ.mol -1 , Coble creep, based on diffusion of materials through grain boundaries, is the dominant rate-controlling mechanism, which contributes to the creep deformation. The formation of slip bands acts as an accommodation mechanism. In the region of middle stress with stress exponent n ∼ 3 and activation energy Q ∼ (195±7) kJ.mol -1 , micro-creep, caused by viscous gliding of dislocations due to the interaction of O atoms with dislocations, controls the deformation. In the high stress region with stress exponent n ∼ 5-6 and activation energy Q ∼ (210±10) kJ.mol -1 , two mechanisms of the climb of edge dislocations (EDC) and the motion of jogged screw dislocation (MJS) contribute to rate controlling process. In test conditions N36 alloy cladding tube behaves a type of creep similar to that noted in class-I (A) alloys

Saturable Absorbing Quantum Wells at 1.08 and 1.55 Micron Wavelengths for Mode Locking of Solid State Lasers

National Research Council Canada - National Science Library

Wicks, Gary

1998-01-01

Multiple quantum well designs were fabricated and tested at 1.55 microns. A series of 17 MBE fabrications were completed with deposits of various AlInAs/GaInAs alloys deposited on Indium Phosphide substrates...

Wurtzite BAlN and BGaN alloys for heterointerface polarization engineering

KAUST Repository

Liu, Kaikai; Sun, Haiding; Alqatari, Feras; Guo, Wenzhe; Liu, Xinwei; Li, Jingtao; Torres Castanedo, Carlos G; Li, Xiaohang

2017-01-01

deformation and the dipole moment difference between the hexagonal and wurtzite structures. The PZ constants exhibit significant bowing because of the large lattice difference between binary alloys. Furthermore, the PZ constants of BxAl1-xN and BxGa1-xN become

Biomineralisation with Saos-2 bone cells on TiSiN sputtered Ti alloys.

Science.gov (United States)

V V, Anusha Thampi; Bendavid, Avi; Martin, P J; Vaithilingam, Vijay; Bean, Penelope A; Evans, Margaret D M; Subramanian, B

2017-07-01

Surface modifications of metallic implants are important in order to protect the underlying metals from the harsh corrosive environment inside the human body and to minimize the losses caused by wear. Recently, researches are carried out in developing bioactive surfaces on metallic implants, which supports the growth and proliferation of cells on to these surfaces. Titanium silicon nitride (TiSiN) hard nanocomposites thin films were fabricated on Ti alloys (Ti-6Al-4V) by pulsed direct current (DC) reactive magnetron sputtering. The films were characterized for its microstructural and electrochemical behavior. The higher charge transfer resistance (Rct) and positive shift in Ecorr value of TiSiN/Ti alloys than the bare Ti-alloys indicates a better corrosion resistance offered by the TiSiN thin films to the underlying substrates. The biological response to TiSiN/Ti alloys and control bare Ti-alloys was measured in vitro using cell-based assays with two main outcomes. Firstly, neither the Ti alloy nor the TiSiN thin film was cytotoxic to cells. Secondly, the TiSiN thin film promoted differentiation of human bone cells above the bare control Ti alloy as measured by alkaline phosphatase and calcium production. TiSiN thin films provide better corrosion resistance and protect the underlying metal from the corrosive environment. The thin film surface is both biocompatible and bioactive as indicated from the cytotoxicity and biomineralization studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Structural Transformation in Fe73.5Nb3Cu1Si15.5B7 Amorphous Alloy Induced by Laser Heating

Science.gov (United States)

Nykyruy, Yu. S.; Mudry, S. I.; Kulyk, Yu. O.; Zhovneruk, S. V.

2018-03-01

The effect of continuous laser irradiation (λ = 1.06 μm) with laser power of 45 W on the structure of Fe73.5Nb3Cu1Si15.5B7 amorphous alloy has been studied using X-ray diffraction and SEM methods. The sample of the ribbon has been placed at a distance from the focal plane of the lens, so a laser beam has been defocused and the diameter of laser spot on the ribbon surface has been about 10 mm. An exposure time τ varied within interval 0.25-0.70 s. Under such conditions structural transformation processes, which depend on the exposure time, have occurred in an irradiated zone. Crystallization process has started at τ = 0.35 s with the formation of α-Fe(Si) nanocrystalline phase, while complete crystallization has occurred at τ = 0.55 s with formation of two nanocrystalline phases: α-Fe(Si) and a hexagonal H-phase.

Experimental evidences for reducing Mg activation energy in high Al-content AlGaN alloy by MgGa δ doping in (AlN)m/(GaN)n superlattice

OpenAIRE

Xiao Wang; Wei Wang; Jingli Wang; Hao Wu; Chang Liu

2017-01-01

P-type doping in high Al-content AlGaN alloys is a main challenge for realizing AlGaN-based deep ultraviolet optoelectronics devices. According to the first-principles calculations, Mg activation energy may be reduced so that a high hole concentration can be obtained by introducing nanoscale (AlN)5/(GaN)1 superlattice (SL) in Al0.83Ga0.17N disorder alloy. In this work, experimental evidences were achieved by analyzing Mg doped high Al-content AlGaN alloys and Mg doped AlGaN SLs as well as MgG...

Electrochemical behavior of hydroxyapatite/TiN multi-layer coatings on Ti alloys

Energy Technology Data Exchange (ETDEWEB)

Kim, Eun-Ju [Department of Dental Materials, Research Center of Nano-Interface Activation for Biomaterials, School of Dentistry, Chosun University (Korea, Republic of); Jeong, Yong-Hoon [Biomechanics and Tissue Engineering Laboratory, Division of Orthodontics, College of Dentistry, The Ohio State University, Columbus, OH (United States); Choe, Han-Cheol, E-mail: hcchoe@chosun.ac.kr [Department of Dental Materials, Research Center of Nano-Interface Activation for Biomaterials, School of Dentistry, Chosun University (Korea, Republic of); Brantley, William A. [Division of Restorative Science and Prosthodontics, College of Dentistry, The Ohio State University, Columbus, OH (United States)

2014-12-01

The electrochemical behavior of hydroxyapatite (HA) and titanium nitride (TiN) multi-layer coatings on Ti–Nb–Zr alloys was investigated by a variety of surface analytical methods. The HA/TiN layers were deposited using a magnetron sputtering system. The HA target was made of human tooth-ash sintered at 1300 °C for 1 h and had an average Ca/P ratio of 1.9. From X-ray diffraction patterns, the Ti–29Nb–5Zr alloy was composed entirely of equiaxed β-phase exhibiting the principal (110) reflection, and the coating exhibited the (111) and (200) reflections for TiN and the (112) and (202) reflections for HA. At the coating surface the HA films consisted of granular particles, and the surface roughness was 4.22 nm. The thickness of the coating layers increased in the order of HA/TiN (lowest), TiN, and HA (highest). Potentiodynamic polarization measurements revealed that the corrosion current density was the lowest, and the corrosion potential and polarization resistance the highest, when the Ti–29Nb–5Zr surface was covered by the HA/TiN film, compared to solely HA or TiN films. - Highlights: • HA/TiN films were deposited by magnetron sputtering on a Ti–29Nb–5Zr biomedical alloy. • The corrosion current density for the HA/TiN films was lower than that of the non-coated alloy. • The polarization resistance of the HA/TiN films was higher than that of the non-coated alloy.

Electrochemical behavior of hydroxyapatite/TiN multi-layer coatings on Ti alloys

International Nuclear Information System (INIS)

Kim, Eun-Ju; Jeong, Yong-Hoon; Choe, Han-Cheol; Brantley, William A.

2014-01-01

The electrochemical behavior of hydroxyapatite (HA) and titanium nitride (TiN) multi-layer coatings on Ti–Nb–Zr alloys was investigated by a variety of surface analytical methods. The HA/TiN layers were deposited using a magnetron sputtering system. The HA target was made of human tooth-ash sintered at 1300 °C for 1 h and had an average Ca/P ratio of 1.9. From X-ray diffraction patterns, the Ti–29Nb–5Zr alloy was composed entirely of equiaxed β-phase exhibiting the principal (110) reflection, and the coating exhibited the (111) and (200) reflections for TiN and the (112) and (202) reflections for HA. At the coating surface the HA films consisted of granular particles, and the surface roughness was 4.22 nm. The thickness of the coating layers increased in the order of HA/TiN (lowest), TiN, and HA (highest). Potentiodynamic polarization measurements revealed that the corrosion current density was the lowest, and the corrosion potential and polarization resistance the highest, when the Ti–29Nb–5Zr surface was covered by the HA/TiN film, compared to solely HA or TiN films. - Highlights: • HA/TiN films were deposited by magnetron sputtering on a Ti–29Nb–5Zr biomedical alloy. • The corrosion current density for the HA/TiN films was lower than that of the non-coated alloy. • The polarization resistance of the HA/TiN films was higher than that of the non-coated alloy

Study of Stark Effect in n-doped 1.55 μm InN0.92yP1-1.92yBiy/InP MQWs

Science.gov (United States)

Bilel, C.; Chakir, K.; Rebey, A.; Alrowaili, Z. A.

2018-05-01

The effect of an applied electric field on electronic band structure and optical absorption properties of n-doped InN0.92y P1-1.92y Bi y /InP multiple quantum wells (MQWs) was theoretically studied using a self-consistent calculation combined with the 16-band anti-crossing model. The incorporation of N and Bi atoms into an InP host matrix leads to rapid reduction of the band gap energy covering a large infrared range. The optimization of the well parameters, such as the well/barrier widths, N/Bi compositions and doping density, allowed us to obtain InN0.92y P1-1.92y Bi y /InP MQWs operating at the wavelength 1.55 μm. Application of the electric field causes a red-shift of the fundamental transition energy T 1 accompanied by a significant change in the spatial distribution of confined electron density. The Stark effect on the absorption coefficient of n-doped InN0.92y P1-1.92y Bi y /InP MQWs was investigated. The Bi composition of these MQWs was adjusted for each electric field value in order to maintain the wavelength emission at 1.55 μm.

Anodic oxidation of Ta/Fe alloys

International Nuclear Information System (INIS)

Mato, S.; Alcala, G.; Thompson, G.E.; Skeldon, P.; Shimizu, K.; Habazaki, H.; Quance, T.; Graham, M.J.; Masheder, D.

2003-01-01

The behaviour of iron during anodizing of sputter-deposited Ta/Fe alloys in ammonium pentaborate electrolyte has been examined by transmission electron microscopy, Rutherford backscattering spectroscopy, glow discharge optical emission spectroscopy and X-ray photoelectron spectroscopy. Anodic films on Ta/1.5 at.% Fe, Ta/3 at.% Fe and Ta/7 at.% Fe alloys are amorphous and featureless and develop at high current efficiency with respective formation ratios of 1.67, 1.60 and 1.55 nm V -1 . Anodic oxidation of the alloys proceeds without significant enrichment of iron in the alloy in the vicinity of the alloy/film interface and without oxygen generation during film growth, unlike the behaviour of Al/Fe alloys containing similar concentrations of iron. The higher migration rate of iron species relative to that of tantalum ions leads to the formation of an outer iron-rich layer at the film surface

Effect of alloying on elastic properties of ZrN based transition metal nitride alloys

KAUST Repository

Kanoun, Mohammed; Goumri-Said, Souraya

2014-01-01

We report the effect of composition and metal sublattice substitutional element on the structural, elastic and electronic properties of ternary transition metal nitrides Zr1-xMxN with M=Al, Ti, Hf, V, Nb, W and Mo. The analysis of the elastic constants, bulk modulus, shear modulus, Young's modulus, and Poisson's ratio provides insights regarding the mechanical behavior of Zr1-xMxN. We predict that ternary alloys are more ductile compared to their parent binary compounds. The revealed trend in the mechanical behavior might help for experimentalists on the ability of tuning the mechanical properties during the alloying process by varying the concentration of the transition metal. © 2014 Elsevier B.V.

Effect of alloying on elastic properties of ZrN based transition metal nitride alloys

KAUST Repository

Kanoun, Mohammed

2014-09-01

We report the effect of composition and metal sublattice substitutional element on the structural, elastic and electronic properties of ternary transition metal nitrides Zr1-xMxN with M=Al, Ti, Hf, V, Nb, W and Mo. The analysis of the elastic constants, bulk modulus, shear modulus, Young\\'s modulus, and Poisson\\'s ratio provides insights regarding the mechanical behavior of Zr1-xMxN. We predict that ternary alloys are more ductile compared to their parent binary compounds. The revealed trend in the mechanical behavior might help for experimentalists on the ability of tuning the mechanical properties during the alloying process by varying the concentration of the transition metal. © 2014 Elsevier B.V.

Experimental evidences for reducing Mg activation energy in high Al-content AlGaN alloy by MgGa δ doping in (AlN)m/(GaN)n superlattice

Science.gov (United States)

Wang, Xiao; Wang, Wei; Wang, Jingli; Wu, Hao; Liu, Chang

2017-03-01

P-type doping in high Al-content AlGaN alloys is a main challenge for realizing AlGaN-based deep ultraviolet optoelectronics devices. According to the first-principles calculations, Mg activation energy may be reduced so that a high hole concentration can be obtained by introducing nanoscale (AlN)5/(GaN)1 superlattice (SL) in Al0.83Ga0.17N disorder alloy. In this work, experimental evidences were achieved by analyzing Mg doped high Al-content AlGaN alloys and Mg doped AlGaN SLs as well as MgGa δ doped AlGaN SLs. Mg acceptor activation energy was significantly reduced from 0.378 to 0.331 eV by using MgGa δ doping in SLs instead of traditional doping in alloys. This new process was confirmed to be able to realize high p-type doping in high Al-content AlGaN.

MicroRNA-155 Inhibition Promoted Wound Healing in Diabetic Rats.

Science.gov (United States)

Ye, Junna; Kang, Yutian; Sun, Xiaofang; Ni, Pengwen; Wu, Minjie; Lu, Shuliang

2017-06-01

Diabetes leads to amputation in approximately 15% to 20% of patients and is associated with high morbidity and mortality. Thus, improving the quality of wound healing in this condition is essential. Diabetes is associated with acute/chronic inflammation affecting all organs especially the foot, while, inhibition of microRNA-155 (miR-155) has been reported to improve or reduce inflammatory situation. However, the role of miR-155 inhibition in promoting diabetic wound healing is not clear. To further study the potential benefit of miR-155 inhibition, a study of male Sprague-Dawley rats was conducted and diabetes was induced by injection of streptozotocin. Real-time polymerase chain reaction (PCR), hematoxylin and eosin staining and immunohistochemistry were then performed. The PCR results confirmed that miR-155 expression was lower after miR-155 inhibition on days 3, 7, and 13 (all Ps healing rate between the normal glucose group (N group), diabetic PBS group (PBS group) and the topical miR-155 inhibitor group was compared. Faster healing of cutaneous wounds was observed in the miR-155 inhibitor group than in the PBS group and normal glucose group ( P healing of diabetic foot wounds.

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

International Nuclear Information System (INIS)

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

1978-01-01

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

First-principle natural band alignment of GaN / dilute-As GaNAs alloy

Directory of Open Access Journals (Sweden)

Chee-Keong Tan

2015-01-01

Full Text Available Density functional theory (DFT calculations with the local density approximation (LDA functional are employed to investigate the band alignment of dilute-As GaNAs alloys with respect to the GaN alloy. Conduction and valence band positions of dilute-As GaNAs alloy with respect to the GaN alloy on an absolute energy scale are determined from the combination of bulk and surface DFT calculations. The resulting GaN / GaNAs conduction to valence band offset ratio is found as approximately 5:95. Our theoretical finding is in good agreement with experimental observation, indicating the upward movements of valence band at low-As content dilute-As GaNAs are mainly responsible for the drastic reduction of the GaN energy band gap. In addition, type-I band alignment of GaN / GaNAs is suggested as a reasonable approach for future device implementation with dilute-As GaNAs quantum well, and possible type-II quantum well active region can be formed by using InGaN / dilute-As GaNAs heterostructure.

Collective effects of interface roughness and alloy disorder in InxGa1-xN/GaN multiple quantum wells

International Nuclear Information System (INIS)

Zeng, K.C.; Smith, M.; Lin, J.Y.; Jiang, H.X.

1998-01-01

The collective effects of alloy disorder and interface roughness on optical properties of In x Ga 1-x N/GaN multiple quantum wells (MQWs) have been studied. The results are compared with those of GaN/AlGaN MQWs and InGaN epilayers. In x Ga 1-x N/GaN MQWs emit a broad and asymmetrical photoluminescence (PL) band, while GaN/AlGaN MQWs and InGaN epilayers emit narrower and Gaussian-shaped PL bands. Furthermore, the decay of excitons at low temperatures in In x Ga 1-x N/GaN MQWs follows a nonexponential function even at the lower-energy side of the PL spectral peak, while those in GaN/AlGaN MQWs and in InGaN epilayers follow a single exponential function. Both alloy disorder and interface roughness have to be included in order to interpret the PL emission spectrum and the decay dynamics in In x Ga 1-x N/GaN MQWs. Important parameters of the In x Ga 1-x N/GaN MQWs, σ x ,σ L , and dτ/dL, denoting the alloy disorder, the interface roughness, and the rate of changing of the exciton decay lifetime with well width, respectively, have been deduced. The method developed here can be used to determine σ x ,σ L , and dτ/dL in any MQW systems with wells being alloy materials. copyright 1998 American Institute of Physics

Layered growth model and epitaxial growth structures for SiCAlN alloys

International Nuclear Information System (INIS)

Liu Zhaoqing; Ni Jun; Su Xiaoao; Dai Zhenhong

2009-01-01

Epitaxial growth structures for (SiC) 1-x (AlN) x alloys are studied using a layered growth model. First-principle calculations are used to determine the parameters in the layered growth model. The phase diagrams of epitaxial growth are given. There is a rich variety of the new metastable polytype structures at x=1/6 ,1/5 ,1/4 ,1/3 , and 1/2 in the layered growth phase diagrams. We have also calculated the electronic properties of the short periodical SiCAlN alloys predicted by our layered growth model. The results show that various ordered structures of (SiC) 1-x (AlN) x alloys with the band gaps over a wide range are possible to be synthesized by epitaxial growth.

Investigation of localization effect in GaN-rich InGaN alloys and ...

Indian Academy of Sciences (India)

Abstract. The temperature-dependent PL properties of GaN-rich InxGa1−xN alloys is investigated and S-shaped temperature dependence is observed in all InGaN samples. It is found that the origin of localization effect in samples. A and B are different from that in sample C. For samples A and B, In content fluctuations ...

BInGaN alloys nearly lattice-matched to GaN for high-power high-efficiency visible LEDs

Science.gov (United States)

Williams, Logan; Kioupakis, Emmanouil

2017-11-01

InGaN-based visible light-emitting diodes (LEDs) find commercial applications for solid-state lighting and displays, but lattice mismatch limits the thickness of InGaN quantum wells that can be grown on GaN with high crystalline quality. Since narrower wells operate at a higher carrier density for a given current density, they increase the fraction of carriers lost to Auger recombination and lower the efficiency. The incorporation of boron, a smaller group-III element, into InGaN alloys is a promising method to eliminate the lattice mismatch and realize high-power, high-efficiency visible LEDs with thick active regions. In this work, we apply predictive calculations based on hybrid density functional theory to investigate the thermodynamic, structural, and electronic properties of BInGaN alloys. Our results show that BInGaN alloys with a B:In ratio of 2:3 are better lattice matched to GaN compared to InGaN and, for indium fractions less than 0.2, nearly lattice matched. Deviations from Vegard's law appear as bowing of the in-plane lattice constant with respect to composition. Our thermodynamics calculations demonstrate that the solubility of boron is higher in InGaN than in pure GaN. Varying the Ga mole fraction while keeping the B:In ratio constant enables the adjustment of the (direct) gap in the 1.75-3.39 eV range, which covers the entire visible spectrum. Holes are strongly localized in non-bonded N 2p states caused by local bond planarization near boron atoms. Our results indicate that BInGaN alloys are promising for fabricating nitride heterostructures with thick active regions for high-power, high-efficiency LEDs.

Genomic organization, transcript variants and comparative analysis of the human nucleoporin 155 (NUP155) gene

DEFF Research Database (Denmark)

Zhang, X.; Yang, J.; Yu, J.

2002-01-01

Nucleoporin 155 (Nup155) is a major component of the nuclear pore complex (NPC) involved in cellular nucleo-cytoplasmic transport. We have acquired the complete sequence and interpreted the genomic organization of the Nup155 orthologos from human (Homo sapiens) and pufferfish (Fugu rubripes), which...... complementary to RNAs of the Nup155 orthologs from Fugu and mouse. Comparative analysis of the Nup155 orthologs in many species, including H. sapiens, Mus musculus, Rattus norvegicus, F. rubripes, Arabidopsis thaliana, Drosophila melanogaster, and Saccharomyces cerevisiae, has revealed two paralogs in S...

Fabrication of welded pipes of the KhN45Yu alloy

International Nuclear Information System (INIS)

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

1977-01-01

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

Preparation and Properties of Ti-TiN-Zr-ZrN Multilayer Films on Titanium Alloy Surface

Directory of Open Access Journals (Sweden)

LIN Song-sheng

2017-06-01

Full Text Available 24 cycles Ti-TiN-Zr-ZrN soft-hard alternating multilayer film was deposited on TC11 titanium alloy by vacuum cathodic arc deposition method. The structure and performance of the multilayer film, especially wear and sand erosion resistance were investigated by various analytical methods including pin on disc wear tester, sand erosion tester, 3D surface topography instrument, scanning electron microscopy (SEM, X-ray diffraction(XRD, micro-hardness tester and scratch adhesion tester. The results indicate that the Vickers-hardness of the multilayer film with thickness of 5.8μm can reach up to 28.10GPa. The adhesive strength of these coatings can be as high as 56N. Wear rate of the multilayer coated alloy is one order of magnitude smaller than bare one, which decreased from 7.06×10-13 m3·N-1·m-1 to 3.03×10-14m3·N-1·m-1. Multilayer films can play the role in hindering the extension of cracks, and thus sand erosion properties of the TC11 titanium alloy substrates are improved.

Laser surface alloying of aluminium-transition metal alloys

Directory of Open Access Journals (Sweden)

Almeida, A.

1998-04-01

Full Text Available Laser surface alloying has been used as a tool to produce hard and corrosion resistant Al-transition metal (TM alloys. Cr and Mo are particularly interesting alloying elements to produce stable highstrength alloys because they present low diffusion coefficients and solid solubility in Al. To produce Al-TM surface alloys a two-step laser process was developed: firstly, the material is alloyed using low scanning speed and secondly, the microstructure is modified by a refinement step. This process was used in the production of Al-Cr, Al-Mo and Al-Nb surface alloys by alloying Cr, Mo or Nb powder into an Al and 7175 Al alloy substrate using a CO₂ laser. This paper presents a review of the work that has been developed at Instituto Superior Tecnico on laser alloying of Al-TM alloys, over the last years.

En el presente trabajo se estudia la aleación superficial mediante láser de aluminio con metales de transición. El cromo y el molibdeno son particularmente interesantes porque producen aleaciones de alta resistencia y por el bajo coeficiente de difusión y solución sólida en aluminio. Para producir estas aleaciones se ha seguido un procedimiento desarrollado en dos partes. En primer lugar, el material se alea usando una baja velocidad de procesado y en segundo lugar la estructura se modifica mediante un refinamiento posterior. Este procedimiento se ha empleado en la producción de aleaciones Al-Cr, Al-Mo y Al-Nb mediante aleación con láser de CO₂ de polvos de Cr, Mo o Nb en aluminio y la aleación 7175. Este trabajo es una revisión del desarrollado en el Instituto Superior Técnico de Lisboa en los últimos años.

Corrosion characteristics of Hastelloy N alloy after He+ ion irradiation

International Nuclear Information System (INIS)

Lin Jianbo; Yu Xiaohan; Li Aiguo; He Shangming; Cao Xingzhong; Wang Baoyi; Li Zhuoxin

2014-01-01

With the goal of understanding the invalidation problem of irradiated Hastelloy N alloy under the condition of intense irradiation and severe corrosion, the corrosion behavior of the alloy after He + ion irradiation was investigated in molten fluoride salt at 700 °C for 500 h. The virgin samples were irradiated by 4.5 MeV He + ions at room temperature. First, the virgin and irradiated samples were studied using positron annihilation lifetime spectroscopy (PALS) to analyze the influence of irradiation dose on the vacancies. The PALS results showed that He + ion irradiation changed the size and concentration of the vacancies which seriously affected the corrosion resistance of the alloy. Second, the corroded samples were analyzed using synchrotron radiation micro-focused X-ray fluorescence, which indicated that the corrosion was mainly due to the dealloying of alloying element Cr in the matrix. Results from weight-loss measurement showed that the corrosion generally correlated with the irradiation dose of the alloy. (author)

Thermodynamic investigations of the Mn-Ni-C-N quarternary alloys by solid-state galvanic cell technique

International Nuclear Information System (INIS)

Teng Lidong; Aune, Ragnhild; Seetharaman, Seshadri

2005-01-01

In view of the important applications of carbides and nitrides of transition metals in the hard materials industries, the thermodynamic activities of manganese in Mn-Ni-C-N alloys have been studied by solid-state galvanic cell technique with CaF 2 as the solid electrolyte. The phase compositions and microstructure of various alloys have been analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Nitrogen was introduced into the alloy by equilibrating with N 2 gas. It was established during the experiments that the solubility of nitrogen in the alloys was affected by the carbon content. A (Mn,Ni) 4 (N,C) nitride was formed during the nitriding procedure in the alloys. The electromotive force (EMF) measurements were carried out in the temperature range 940-1127 K in order to determine the activities of Mn in the alloys. The activities of manganese were calculated and compared with those of the corresponding Mn-Ni-C ternary alloys

29 CFR 500.155 - Authority.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Authority. 500.155 Section 500.155 Labor Regulations... AGRICULTURAL WORKER PROTECTION Enforcement Agreements with Federal and State Agencies § 500.155 Authority...) to Federal and State agencies such authority (other than rulemaking) as he determines may be useful...

21 CFR 155.194 - Catsup.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Catsup. 155.194 Section 155.194 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED VEGETABLES Requirements for Specific Standardized Canned Vegetables § 155.194 Catsup. (a...

Evaluation of cast Ti-Fe-O-N alloys for dental applications

International Nuclear Information System (INIS)

Koike, Marie; Ohkubo, Chikahiro; Sato, Hideki; Fujii, Hideki; Okabe, Toru

2005-01-01

Good mechanical properties, biocompatibility and corrosion resistance make titanium an excellent material for biomedical applications. However, when better mechanical properties than those offered by commercially pure titanium (CPTi) are needed, Ti-6Al-4V is sometimes a good alternative. Some new titanium alloys, developed as industrial structural materials, aim at an intermediate range of strength between that of CP Ti and Ti-6Al-4V. Two of these alloys are Super-TIX800TM (Ti-1% Fe-0.35% O-0.01% N) and Super-TIX800NTM (Ti-1% Fe-0.3% O-0.04% N) (both produced by Nippon Steel Corp., Japan). Besides being stronger than CP Ti, the cost of manufacturing these alloys is reportedly lower than for Ti-6Al-4V since they do not contain any expensive elements. In addition, they are not composed of elements such as aluminum or vanadium, which have caused biocompatibility concerns in medical and dental appliances. To evaluate these alloys as candidates for dental use, it is helpful to compare them to CP Ti (ASTM Grade 2) and Ti-6Al-4V (ASTM Grade 5), which have already been employed in dentistry. We evaluated the tensile properties, mold filling capacity, corrosion characteristics and grindability of these industrial alloys prepared by investment casting. Compared to the strengths of cast CPTi, the yield strength and tensile strength of these cast alloys were more than 20% and approximately 30% higher, respectively. On the other hand, both of these properties were 30% lower than for Ti-6Al-4V. Better grindability and wear resistance were additional benefits of these new alloys for dental applications

40 CFR 96.155 - Banking.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Banking. 96.155 Section 96.155 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NOX BUDGET... Tracking System § 96.155 Banking. (a) CAIR NOX allowances may be banked for future use or transfer in a...

The effects of N+ implantation on the wear and friction of type 304 and 15-5 PH stainless steels

International Nuclear Information System (INIS)

Yost, F.G.; Picraux, S.T.; Follstaedt, D.M.; Pope, L.E.; Knapp, J.A.

1983-01-01

Ion implantation of N + into mechanically polished type 304 and 15-5 PH stainless steels was studied to determine its effect on dry wear and friction behavior. Implantation of 4.0 X 10 17 N + cm -2 at 50 keV yielded a depth profile with a peak concentration of about 45 at.% at a depth of 70 nm which dropped to about 10 at.% at 120 nm. Wear and friction were studied in an unlubricated pin-on-disc configuration using type 304 and 440C stainless steel pins. Both N + -implanted steels exhibited reduced wear at low loads but no significant reduction in the coefficient of friction was found. At the lowest normal load studied (12.3 gf), the average maximum wear depth of the implanted 15-5 PH stainless steel disc (about 0.1 μm) was reduced to approximately 10% of that for the corresponding unimplanted pin-on-disc pair after 1000 cycles. At normal loads of 50 gf or above (corresponding to hertzian stresses of 1160 MPa or higher) all beneficial effects were gone. Vacuum heat treatment at 923 K for 1.8 ks of an identically implanted type 304 stainless steel specimen eradicated the beneficial effects of the nitrogen implantation. The N + -implanted discs show similar reductions in wear to discs implanted with titanium and carbon, but the N + -implanted discs do not exhibit the reductions in the coefficient of friction seen with the discs implanted with titanium and carbon. (Auth.)

Early stages of the mechanical alloying of TiC–TiN powder mixtures

International Nuclear Information System (INIS)

Mura, Giovanna; Musu, Elodia; Delogu, Francesco

2013-01-01

The present work focuses on the alloying behavior of TiC–TiN powder mixtures submitted to mechanical processing by ball milling. Accurate X-ray diffraction analyses indicate a progressive modification of the unit cell parameters of the TiC and TiN phases, suggesting the formation of TiC- and TiN-rich solid solutions with an increasingly larger content of solutes. Once the discrete character of the mechanical treatment is taken into due account, the smooth change of the unit cell parameters can be explained by a sequence of mutual dissolution stages related to individual collisions. At each collision, the average chemical composition of small amounts of TiC- and TiN-rich phases changes discontinuously. The discontinuous changes can be tentatively ascribed to local mass transport processes activated by the mechanical deformation of powders at collisions. -- Highlights: ► Mechanically processed TiC–TiN powder mixtures form two solid solutions. ► An analytical model was developed to describe the mechanical alloying kinetics. ► The amount of powder alloyed at collision was indirectly estimated. ► A few nanomoles of material participate in the alloying process at each collision. ► The chemical composition of the solid solutions was shown to change discontinuously.

32 CFR 155.3 - Definitions.

Science.gov (United States)

2010-07-01

... to classified information needed in connection with his or her employment in the private sector; any... 32 National Defense 1 2010-07-01 2010-07-01 false Definitions. 155.3 Section 155.3 National... SECURITY CLEARANCE PROGRAM § 155.3 Definitions. (a) Applicant. Any U.S. citizen who holds or requires a...

Alloy spreading and filling of gaps in brazing of VDU-2 and KhN50VMTYuB heat resistant nickel alloys with VPr3K and VPr10 alloys

International Nuclear Information System (INIS)

Shapiro, A.E.; Podol'skij, B.A.; Lepisko, M.R.; Borzyak, A.G.; Moryakov, V.F.; Rostislavskaya, T.T.

1984-01-01

A study was made on contact interaction of VDU-2 and KhN50VMTYuB alloys with VPr3K and VPr10 alloys at 1325 and 1220 deg C in argon and industrial vacuum. The contact angles and wettability indexes were determined. The solders fill the vertical gaps of up to 0.25 mm width through 80 mm height. Spreading and filling of gaps proceeds better during soldering in argon with boron trifluoride addition as compared to soldering in industrial vacuum. VPr10 alloy is divided into two phases when wetting KhN50VMTYuB alloy: fusible one on the base of nickel-chromium-manganese solution and infusible one on the base of nickel-niobium eutectics. The square of fusible phase spreading is 2.5...3 times larger as compared to infusible one

12 CFR 308.155 - Hearing.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Hearing. 308.155 Section 308.155 Banks and... Pursuant to Section 32 of the FDIA § 308.155 Hearing. (a) Hearing dates. The Executive Secretary shall order a hearing to be commenced within 30 days after receipt of a request for a hearing filed pursuant...

Effects of fabrication practices and techniques on the corrosion and mechanical properties of Ni-Cr-Mo nickel based alloys UNS N10276, N06022, N06686, and N06625

International Nuclear Information System (INIS)

Hinshaw, E.B.; Crum, J.R.

1996-01-01

Ni-Cr-Mo alloys have excellent resistance to both oxidizing and reducing type environments; however, heat treating, surface condition, welding, and type of welding consumable can have a significant affect on the corrosion resistance and mechanical properties of these alloys. It is also important when performing standard ASTM intergranular corrosion tests on welded test coupons to make an accurate comparison of alloys being tested. A standard weld procedure and consistent post-weld sample conditioning method should be incorporated into the comparison test program. An evaluation of the effect of various fabrication practices on the corrosion resistance of the alloy was performed using accelerated corrosion tests ASTM G28B. The fabrication conditions examined were as-welded, welded-pickled, welded-annealed-pickled, welded annealed ground, welded-ground, using over matching filler metals, and various levels of heat input. In addition to fabrication techniques, the effect of ASTM G28B test duration on corrosion rates of UNS N10276, N06022, N06686, and N06625 was evaluated. ASTM G28A intergranular corrosion and mechanical testing using welded coupons of UNS N06625 were also performed to determine the affect of post-weld annealing and aging heat treatments on the corrosion resistance and mechanical properties of UNS N06625

Optimización topológica y fabricación aditiva de un soporte aeronáutico mediante sinterizado láser de acero inoxidable 15-5PH

OpenAIRE

Marchal Montes, Álvaro

2016-01-01

El objetivo de este trabajó será la aplicación de la optimización topológica a un soporte usado en el sector aeronáutico para reducir su masa que posteriormente se fabricará mediante fabricación aditiva con tecnología DMLS (Direct Metal Laser Sintering) en acero inoxidable 15-5PH. Para llegar a una buena optimización topológica será necesario estudiar todos los caminos de optimización posibles hasta llegar a una correcta mediante softwares adecuados además de adaptarla a la fabricación ad...

Early stages of the mechanical alloying of TiC-TiN powder mixtures

Energy Technology Data Exchange (ETDEWEB)

Mura, Giovanna [Dipartimento di Ingegneria Elettrica ed Elettronica, Universita degli Studi di Cagliari, via Marengo 2, 09123 Cagliari (Italy); Musu, Elodia [Industrial Telemicroscopy Laboratory, Sardegna Ricerche, Polaris, Technology Park of Sardinia, Edificio 3, Loc. Piscinamanna, 09010 Pula (Italy); Delogu, Francesco, E-mail: francesco.delogu@dimcm.unica.it [Dipartimento di Ingegneria Meccanica, Chimica, e dei Materiali, Universita degli Studi di Cagliari, via Marengo 2, I-09123 Cagliari (Italy)

2013-01-15

The present work focuses on the alloying behavior of TiC-TiN powder mixtures submitted to mechanical processing by ball milling. Accurate X-ray diffraction analyses indicate a progressive modification of the unit cell parameters of the TiC and TiN phases, suggesting the formation of TiC- and TiN-rich solid solutions with an increasingly larger content of solutes. Once the discrete character of the mechanical treatment is taken into due account, the smooth change of the unit cell parameters can be explained by a sequence of mutual dissolution stages related to individual collisions. At each collision, the average chemical composition of small amounts of TiC- and TiN-rich phases changes discontinuously. The discontinuous changes can be tentatively ascribed to local mass transport processes activated by the mechanical deformation of powders at collisions. -- Highlights: Black-Right-Pointing-Pointer Mechanically processed TiC-TiN powder mixtures form two solid solutions. Black-Right-Pointing-Pointer An analytical model was developed to describe the mechanical alloying kinetics. Black-Right-Pointing-Pointer The amount of powder alloyed at collision was indirectly estimated. Black-Right-Pointing-Pointer A few nanomoles of material participate in the alloying process at each collision. Black-Right-Pointing-Pointer The chemical composition of the solid solutions was shown to change discontinuously.

Influence of heat treatment on the strength and fracture toughness of 7N01 aluminum alloy

Energy Technology Data Exchange (ETDEWEB)

Li, Bo [School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Wang, Xiaomin, E-mail: xmwang991011@163.com [School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Chen, Hui; Hu, Jie [School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Huang, Cui [School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Gou, Guoqing [School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China)

2016-09-05

7N01 aluminum (Al) alloys are treated by five heat treatment methods as peak aging (T6), over aging (T74), high temperature and subsequently low temperature aging (HLA), retrogression and reaging (RRA) and double retrogression and reaging (DRRA). The strength and fracture toughness of the five samples are tested, and the microstructures are investigated by optical microscopy (OM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results show that 7N01 Al-alloy treated at T6 condition has high strength but low fracture toughness. Compared with T6 treatment, T74 and HLA treatments increase the fracture toughness by 67% and 90% respectively, while the strength decrease by 9% and 17%. RRA process is a proper treatment method for 7N01 which improves the fracture toughness without sacrificing strength. The fracture toughness of DRRA treated alloy is much lower than that of RRA. Quantitative analysis through TEM images shows that the heat treatment affects the mechanical properties of 7N01 Al-alloy highly through changing the precipitates in grains and on grain boundaries, which can be explained by the coherency strengthening mechanism and Orowan mechanism. - Highlights: • Five heat treatments which can change the properties of 7N01 Al alloy were designed. • Quantitative analysis of precipitates was employed to study the mechanism. • RRA treatment can make proper strength/toughness property balances for 7N01 Al alloy.

Influence of heat treatment on the strength and fracture toughness of 7N01 aluminum alloy

International Nuclear Information System (INIS)

Li, Bo; Wang, Xiaomin; Chen, Hui; Hu, Jie; Huang, Cui; Gou, Guoqing

2016-01-01

7N01 aluminum (Al) alloys are treated by five heat treatment methods as peak aging (T6), over aging (T74), high temperature and subsequently low temperature aging (HLA), retrogression and reaging (RRA) and double retrogression and reaging (DRRA). The strength and fracture toughness of the five samples are tested, and the microstructures are investigated by optical microscopy (OM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results show that 7N01 Al-alloy treated at T6 condition has high strength but low fracture toughness. Compared with T6 treatment, T74 and HLA treatments increase the fracture toughness by 67% and 90% respectively, while the strength decrease by 9% and 17%. RRA process is a proper treatment method for 7N01 which improves the fracture toughness without sacrificing strength. The fracture toughness of DRRA treated alloy is much lower than that of RRA. Quantitative analysis through TEM images shows that the heat treatment affects the mechanical properties of 7N01 Al-alloy highly through changing the precipitates in grains and on grain boundaries, which can be explained by the coherency strengthening mechanism and Orowan mechanism. - Highlights: • Five heat treatments which can change the properties of 7N01 Al alloy were designed. • Quantitative analysis of precipitates was employed to study the mechanism. • RRA treatment can make proper strength/toughness property balances for 7N01 Al alloy.

FINEMET type alloy without Si: Structural and magnetic properties

International Nuclear Information System (INIS)

Muraca, D.; Cremaschi, V.; Moya, J.; Sirkin, H.

2008-01-01

Magnetic and structural properties of a Finemet type alloy (Fe 73.5 Ge 15.5 Nb 3 B 7 Cu 1 ) without Si and high Ge content were studied. Amorphous material was obtained by the melt spinning technique and was heat treated at different temperatures for 1 h under high vacuum to induce the nanocrystallization of the sample. The softest magnetic properties were obtained between 673 and 873 K. The role of Ge on the ferromagnetic paramagnetic transition of the as-quenched alloys and its influence on the crystallization process were studied using a calorimetric technique. Moessbauer spectroscopy was employed in the nanocrystallized alloy annealed at 823 K to obtain the composition of the nanocrystals and the amorphous phase fraction. Using this data and magnetic measurements of the as-quenched alloy, the magnetic contribution of nanocrystals to the alloy annealed at 823 K was estimated via a linear model

Alloy scattering dependence of electron transport in AlGaN

International Nuclear Information System (INIS)

Yarar, Z.; Ozdemir, M.

2010-01-01

The electron transport and velocity characteristics in AlGaN are examined using an ensemble Monte Carlo simulation method. A three valley band structure model where nonparabolicity effects are considered in all valleys is used for Monte Carlo calculations. All of the major electron scattering interactions like acoustic and optical phonon, intervaley, ionized impurity and alloy disorder scatterings are included in the calculations. The velocity-applied electric field characteristics are analyzed as a function of Al molar fraction and temperature in the ranges of x=0.1 to x=0.5 and 77 K to 500 K, respectively. The velocity overshoot is clearly observed and the population of valleys seems well-matched with the occupancy of valleys in AlGaN. The results of electron steady state velocity-field curves are found that the alloy disorder scattering has important effects on the electron transport characteristics of AlGaN.

Growth and properties of Al-rich InxAl1-xN ternary alloy grown on GaN template by metalorganic chemical vapour deposition

International Nuclear Information System (INIS)

Oh, Tae Su; Suh, Eun-Kyung; Kim, Jong Ock; Jeong, Hyun; Lee, Yong Seok; Nagarajan, S; Lim, Kee Young; Hong, Chang-Hee

2008-01-01

An Al-rich In x Al 1-x N ternary alloy was grown on a GaN template by metal-organic chemical vapour deposition (MOCVD). The GaN template was fabricated on a c-plane sapphire with a low temperature GaN nucleation layer. The growth of the 300 nm thick In x Al 1-x N layer was carried out under various growth temperatures and pressures. The surface morphology and the InN molar fraction of the In x Al 1-x N layer were assessed by using atomic force microscopy (AFM) and high resolution x-ray diffraction, respectively. The AFM surface images of the In x Al 1-x N ternary alloy exhibited quantum dot-like grains caused by the 3D island growth mode. The grains, however, disappeared rapidly by increasing diffusion length and mobility of the Al adatoms with increasing growth temperature and the full width at half maximum value of ternary peaks in HR-XRD decreased with decreasing growth pressure. The MOCVD growth condition with the increased growth temperature and decreased growth pressure would be effective to grow the In x Al 1-x N ternary alloy with a smooth surface and improved quality. The optical band edge of In x Al 1-x N ternary alloys was estimated by optical absorbance and, based on the results of HR-XRD and optical absorbance measurements, we obtained the bowing parameter of the In x Al 1-x N ternary alloy at b = 5.3 eV, which was slightly larger than that of previous reports

High pressure stability analysis and chemical bonding of Ti1-xZrxN alloy: A first principle study

International Nuclear Information System (INIS)

Chauhan, Mamta; Gupta, Dinesh C.

2016-01-01

First-principles pseudo-potential calculations have been performed to analyze the stability of Ti 1-x Zr x N alloy under high pressures. The first order phase transition from B1 to B2 phase has been observed in this alloy at high pressure. The variation of lattice parameter with the change in concentration of Zr atom in Ti 1-x Zr x N is also reported in both the phases. The calculations for density of states have been performed to understand the alloying effects on chemical bonding of Ti-Zr-N alloy.

Investigation of strain effects on phase diagrams in the ternary nitride alloys (InAlN, AlGaN, InGaN)

Energy Technology Data Exchange (ETDEWEB)

Mohamad, Ranim; Chen, Jun; Ruterana, Pierre [CIMAP, UMR 6252, CNRS-ENSICAEN-CEA-UNICAEN, Caen (France); Bere, Antoine [Laboratoire de Physique et de Chimie de l' Environnement, Universite Ouaga I Pr Joseph KI-ZERBO, Ouagadougou (Burkina Faso)

2017-09-15

In this work, we used a modified Stillinger-Weber potential and a methodology of free energy calculation based on numerical computation of the configuration partition function of an alloy, to make a comprehensive study of the properties of group-III nitride ternary compounds (In{sub x}Ga{sub 1-x}N; In{sub x}Al{sub 1-x}N; Al{sub x}Ga{sub 1-x}N). The wurtzite structure was used; and the critical temperatures for the random ternary alloys are determined as 2717 K for In{sub x}Al{sub 1-x}N, 1718 K for In{sub x}Ga{sub 1-x}N, and 177 K for Al{sub x}Ga{sub 1-x}N, respectively. Therefore, Al{sub x}Ga{sub 1-x}N has no unstable mixing region at typical growth temperatures around 1100 C. In contrast, In{sub x}Al{sub 1-x}N and In{sub x}Ga{sub 1-x}N exhibit a wide unstable region, which means that being thick layers, their stability as homogeneous alloys is probably limited. In agreement with other reports, it is also pointed out that the critical temperature T{sub c} may be decreased when the layers are grown under strain. Although the compression and extension have the same effect below 1.5% strain, it is shown, for the first time, that when the compressive strain goes beyond, T{sub c} abruptly increases in contrast to the case of tensile strain where it continues to decrease. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Phonon structures of GaN-based random semiconductor alloys

Science.gov (United States)

Zhou, Mei; Chen, Xiaobin; Li, Gang; Zheng, Fawei; Zhang, Ping

2017-12-01

Accurate modeling of thermal properties is strikingly important for developing next-generation electronics with high performance. Many thermal properties are closely related to phonon dispersions, such as sound velocity. However, random substituted semiconductor alloys AxB1-x usually lack translational symmetry, and simulation with periodic boundary conditions often requires large supercells, which makes phonon dispersion highly folded and hardly comparable with experimental results. Here, we adopt a large supercell with randomly distributed A and B atoms to investigate substitution effect on the phonon dispersions of semiconductor alloys systematically by using phonon unfolding method [F. Zheng, P. Zhang, Comput. Mater. Sci. 125, 218 (2016)]. The results reveal the extent to which phonon band characteristics in (In,Ga)N and Ga(N,P) are preserved or lost at different compositions and q points. Generally, most characteristics of phonon dispersions can be preserved with indium substitution of gallium in GaN, while substitution of nitrogen with phosphorus strongly perturbs the phonon dispersion of GaN, showing a rapid disintegration of the Bloch characteristics of optical modes and introducing localized impurity modes. In addition, the sound velocities of both (In,Ga)N and Ga(N,P) display a nearly linear behavior as a function of substitution compositions. Supplementary material in the form of one pdf file available from the Journal web page at http://https://doi.org/10.1140/epjb/e2017-80481-0.

Critical parameters for the molecular beam epitaxial growth of 1.55 μm (Ga,In)(N,As) multiple quantum wells

International Nuclear Information System (INIS)

Ishikawa, Fumitaro; Luna, Esperanza; Trampert, Achim; Ploog, Klaus H.

2006-01-01

The authors discuss the effect of substrate temperature and As beam equivalent pressure (BEP) on the molecular beam epitaxial growth of (Ga,In)(N,As) multiple quantum wells (MQWs). Transmission electron microscopy studies reveal that a low substrate temperature essentially prevents composition modulations. Secondary ion mass spectrometry results indicate that a low As BEP reduces the incorporation competition of group V elements. The low substrate temperature and low As BEP growth condition leads to (Ga,In)(N,As) MQWs containing more than 4% N preserving good structural and optical properties, and hence demonstrating 1.55 μm photoluminescence emission at room temperature

Wear and Friction Characteristics of AlN/Diamond-Like Carbon Hybrid Coatings on Aluminum Alloy

Science.gov (United States)

Nakamura, Masashi; Kubota, Sadayuki; Suzuki, Hideto; Haraguchi, Tadao

2015-10-01

The use of diamond-like carbon (DLC) coatings has the potential to greatly improve the wear resistance and friction of aluminum alloys, but practical application has so far been limited by poor adhesion due to large difference in hardness and elasticity between the two materials. This study investigates the deposition of DLC onto an Al-alloy using an intermediate AlN layer with a graded hardness to create a hybrid coating. By controlling the hardness of the AlN film, it was found that the wear life of the DLC film could be improved 80-fold compared to a DLC film deposited directly onto Al-alloy. Furthermore, it was demonstrated through finite element simulation that creating a hardness gradient in the AlN intermediate layer reduces the distribution of stress in the DLC film, while also increasing the force of adhesion between the DLC and AlN layers. Given that both the DLC and AlN films were deposited using the same unbalanced magnetron sputtering method, this process is considered to represent a simple and effective means of improving the wear resistance of Al-alloy components commonly used within the aerospace and automotive industries.

14 CFR 155.3 - Applicable law.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Applicable law. 155.3 Section 155.3... RELEASE OF AIRPORT PROPERTY FROM SURPLUS PROPERTY DISPOSAL RESTRICTIONS § 155.3 Applicable law. (a... transfer to the requirements of applicable law. Based on the laws cited in this paragraph, the...

Half Life Measurements in 155Gd

International Nuclear Information System (INIS)

Malmskog, S.G.

1966-08-01

In the literature there exists a definite difference for the half life of the 86.5 keV level in Gd depending on whether 155 Eu or 155 Tb sources have been used. Using a good energy resolution electron-electron coincidence spectrometer and a 155 Eu source, a half life of 6.48 ± 0.26 nsec was obtained for the 86.5 keV level. This is in agreement with the values previously measured with 155 Tb sources. The half life of the 105.4 keV level was measured to be 1.12 ± 0.05 nsec

Study of wurtzite and zincblende GaN/InN based solar cells alloys: First-principles investigation within the improved modified Becke-Johnson potential

KAUST Repository

Ul Haq, Bakhtiar

2014-09-01

Wurtzite GaInN alloys with flexible energy gaps are pronounced for their potential applications in optoelectronics and solar cell technology. Recently the unwanted built-in fields caused by spontaneous polarization and piezoelectric effects in wurtzite (WZ) GaInN, has turned the focus towards zinc-blende (ZB) GaInN alloys. To comprehend merits and demerits of GaInN alloys in WZ and ZB structures, we performed a comparative study of the structural, electronic and optical properties of Ga1-xInxN alloys with different In concentration using first-principles methodology with density function theory with generalized gradient approximations (GGA) and modified Becke-Johnson (mBJ) potential. Investigations pertaining to total energy of GaInN for the both phases, demonstrate a marginal difference, reflecting nearly equivalent stability of the ZB-GaInN to WZ-GaInN. The larger ionic radii of indium (In), result in larger values of lattice parameters of Ga1-xInxN with higher In concentration. For In deficient Ga1-xInxN, at first, the formation enthalpies increase rapidly as the In content approaches to 45% in WZ and 47% in ZB, and then decreases with the further increase in In concentration. ZB-Ga1-xInxN alloys exhibit comparatively narrower energy gaps than WZ, and get smaller with increase in In contents. The smaller values of effective masses of free carriers, in WZ phase, than ZB phase, reflect higher carrier mobility and electrical conductivity of WZ-Ga1-xInxN. Moreover wide energy gap of WZ-Ga1-xInxN results in large values of the absorption coefficients comparatively and smaller static refractive indices compared to ZB-Ga1-xInxN. Comparable electronic and optical characteristics of the ZB-Ga1-xInxN to WZ-Ga1-xInxN endorses it a material of choice for optoelectronics and solar cell applications besides the WZ-Ga1-xInxN. © 2014 Elsevier Ltd.

Study of wurtzite and zincblende GaN/InN based solar cells alloys: First-principles investigation within the improved modified Becke-Johnson potential

KAUST Repository

Ul Haq, Bakhtiar; Ahmed, Rashid; Shaari, Amiruddin; El Haj Hassan, Fouad; Kanoun, Mohammed; Goumri-Said, Souraya

2014-01-01

Wurtzite GaInN alloys with flexible energy gaps are pronounced for their potential applications in optoelectronics and solar cell technology. Recently the unwanted built-in fields caused by spontaneous polarization and piezoelectric effects in wurtzite (WZ) GaInN, has turned the focus towards zinc-blende (ZB) GaInN alloys. To comprehend merits and demerits of GaInN alloys in WZ and ZB structures, we performed a comparative study of the structural, electronic and optical properties of Ga1-xInxN alloys with different In concentration using first-principles methodology with density function theory with generalized gradient approximations (GGA) and modified Becke-Johnson (mBJ) potential. Investigations pertaining to total energy of GaInN for the both phases, demonstrate a marginal difference, reflecting nearly equivalent stability of the ZB-GaInN to WZ-GaInN. The larger ionic radii of indium (In), result in larger values of lattice parameters of Ga1-xInxN with higher In concentration. For In deficient Ga1-xInxN, at first, the formation enthalpies increase rapidly as the In content approaches to 45% in WZ and 47% in ZB, and then decreases with the further increase in In concentration. ZB-Ga1-xInxN alloys exhibit comparatively narrower energy gaps than WZ, and get smaller with increase in In contents. The smaller values of effective masses of free carriers, in WZ phase, than ZB phase, reflect higher carrier mobility and electrical conductivity of WZ-Ga1-xInxN. Moreover wide energy gap of WZ-Ga1-xInxN results in large values of the absorption coefficients comparatively and smaller static refractive indices compared to ZB-Ga1-xInxN. Comparable electronic and optical characteristics of the ZB-Ga1-xInxN to WZ-Ga1-xInxN endorses it a material of choice for optoelectronics and solar cell applications besides the WZ-Ga1-xInxN. © 2014 Elsevier Ltd.

Advanced Mechanical Properties of a Powder Metallurgy Ti-Al-N Alloy Doped with Ultrahigh Nitrogen Concentration

Science.gov (United States)

Shen, J.; Chen, B.; Umeda, J.; Kondoh, K.

2018-03-01

Titanium and its alloys are recognized for their attractive properties. However, high-performance Ti alloys are often alloyed with rare or noble-metal elements. In the present study, Ti alloys doped with only ubiquitous elements were produced via powder metallurgy. The experimental results showed that pure Ti with 1.5 wt.% AlN incorporated exhibited excellent tensile properties, superior to similarly extruded Ti-6Al-4V. Further analysis revealed that its remarkably advanced strength could primarily be attributed to nitrogen solid-solution strengthening, accounting for nearly 80% of the strength increase of the material. In addition, despite the ultrahigh nitrogen concentration up to 0.809 wt.%, the Ti-1.5AlN sample showed elongation to failure of 10%. This result exceeds the well-known limitation for nitrogen (over 0.45 wt.%) that causes embrittlement of Ti alloys.

Stress Corrosion Cracking Behavior of LD10 Aluminum Alloy in UDMH and N2O4 propellant

Science.gov (United States)

Zhang, Youhong; Chang, Xinlong; Liu, Wanlei

2018-03-01

The LD10 aluminum alloy double cantilever beam specimens were corroded under the conditions of Unsymmetric Uimethyl Hydrazine (UDMH), Dinitrogen Tetroxide (N2O4), and 3.5% NaCl environment. The crack propagation behavior of the aluminum alloy in different corrosion environment was analyzed. The stress corrosion cracking behavior of aluminum alloy in N2O4 is relatively slight and there are not evident stress corrosion phenomenons founded in UDMH.

Interfacial microstructure of Si{sub 3}N{sub 4}/Si{sub 3}N{sub 4} brazing joint with Cu-Zn-Ti filler alloy

Energy Technology Data Exchange (ETDEWEB)

Zhang, J. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)], E-mail: hitzhangjie@hit.edu.cn; Zhang, X.M.; Zhou, Y. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Naka, M. [Joining and Welding Research Institute, Osaka University, Ibaraki, Osaka 567-0047 (Japan); Svetlana, Atroshenko [Faculty of Mathematics and Mechanics, Saint-Petersburg State University (Russian Federation)

2008-11-15

In this study, Si{sub 3}N{sub 4} ceramic was jointed by a brazing technique with a Cu-Zn-Ti filler alloy. The interfacial microstructure between Si{sub 3}N{sub 4} ceramic and filler alloy in the Si{sub 3}N{sub 4}/Si{sub 3}N{sub 4} joint was observed and analyzed by using electron-probe microanalysis, X-ray diffraction and transmission electron microscopy. The results indicate that there are two reaction layers at the ceramic/filler interface in the joint, which was obtained by brazing at a temperature and holding time of 1223 K and 15 min, respectively. The layer nearby the Si{sub 3}N{sub 4} ceramic is a TiN layer with an average grain size of 100 nm, and the layer nearby the filler alloy is a Ti{sub 5}Si{sub 3}N{sub x} layer with an average grain size of 1-2 {mu}m. Thickness of the TiN and Ti{sub 5}Si{sub 3}N{sub x} layers is about 1 {mu}m and 10 {mu}m, respectively. The formation mechanism of the reaction layers was discussed. A model showing the microstructure from Si{sub 3}N{sub 4} ceramic to filler alloy in the Si{sub 3}N{sub 4}/Si{sub 3}N{sub 4} joint was provided as: Si{sub 3}N{sub 4} ceramic/TiN reaction layer/Ti{sub 5}Si{sub 3}N{sub x} reaction layer/Cu-Zn solution.

32 CFR 644.155 - General.

Science.gov (United States)

2010-07-01

... Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Acquisition Acquisition of Rights-Of-Entry § 644.155 General. Sections 644.155 through 644.157 describe the... procedures are applicable to all Division and district Engineers having real estate responsibilities. ...

Effect of N+Cr alloying on the microstructures and tensile properties of Hadfield steel

International Nuclear Information System (INIS)

Chen, C.; Zhang, F.C.; Wang, F.; Liu, H.; Yu, B.D.

2017-01-01

The microstructures and tensile behaviors of traditional Hadfield steel, named Mn12 steel, and Hadfield steel alloyed with N+Cr, named Mn12CrN steel were studied through optical microscopy, transmission electron microscopy, and scanning electron microscopy, among others. Three different tensile strain rates of 5×10 −4 , 5×10 −3 , and 5×10 −2 s −1 were selected in the tensile test. The deformation microstructures and fracture morphologies of the two steels after fracture in the tensile test were observed to analyze the tensile deformation response to different tensile strain rates. Results showed that the grain size of Mn12CrN steel was evidently refined after alloying with N+Cr. The grain would not become abnormally coarse even with increasing austenitizing temperature. During tensile deformation, the strength and plasticity of Mn12CrN steel were superior to those of Mn12 steel at the same strain rate. With increasing the strain rate, the changes in strength and plasticity of Mn12CrN steel were less sensitive to tensile strain rate compared with Mn12 steel. The effects of grain refinement and N+Cr alloying on dynamic strain aging and deformation twining behaviors were responsible for this lack of sensitivity to strain rate.

Role of Ag-alloy in the thermal stability of Ag-based ohmic contact to GaN(0 0 0 1) surface

International Nuclear Information System (INIS)

Xiong, Zhihua; Qin, Zhenzhen; Zhao, Qian; Chen, Lanli

2015-01-01

First-principles calculations are performed to study Ag and Ag-alloy adsorption stability on GaN(0 0 0 1) surface. We find Ag only contact to GaN surface is unstable under high temperature. While Ag-alloy adsorption exhibits better adsorption stability and electronic properties than that of the Ag only contact,due to the enhanced interaction between Ag-alloy and GaN(0 0 0 1) surface. The Ag-alloy, particularly AgNi, is proposed to be used as very promising ohmic contact to GaN for practical applications

32 CFR 155.1 - Purpose.

Science.gov (United States)

2010-07-01

... 32 National Defense 1 2010-07-01 2010-07-01 false Purpose. 155.1 Section 155.1 National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE SECURITY DEFENSE INDUSTRIAL PERSONNEL SECURITY... Industrial Personnel Security Clearance Review Program implementing E.O. 10865, as amended. [57 FR 5383, Feb...

40 CFR 97.155 - Banking.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Banking. 97.155 Section 97.155 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL NOX... Banking. (a) CAIR NOX allowances may be banked for future use or transfer in a compliance account or a...

Linear and nonlinear optical absorption coefficients and refractive index changes in GaN/Al{sub x}Ga{sub (1−x)}N double quantum wells operating at 1.55 μm

Energy Technology Data Exchange (ETDEWEB)

Dakhlaoui, Hassen [Department of Physics, College of Science for Girls, University of Dammam (UOD), Saudi Arabia and Department of Physics, Faculty of Sciences of Bizerte, University of Carthage (Tunisia)

2015-04-07

In the present paper, the linear and nonlinear optical absorption coefficients and refractive index changes between the ground and the first excited states in double GaN/Al{sub x}Ga{sub (1−x)}N quantum wells are studied theoretically. The electronic energy levels and their corresponding wave functions are obtained by solving Schrödinger-Poisson equations self-consistently within the effective mass approximation. The obtained results show that the optical absorption coefficients and refractive index changes can be red- and blue-shifted through varying the left quantum well width and the aluminum concentration x{sub b2} of the central barrier, respectively. These structural parameters are found to present optimum values for carrying out the transition of 0.8 eV (1.55 μm). Furthermore, we show that the desired transition can also be achieved by replacing the GaN in the left quantum well with Al{sub y}Ga{sub (1−y)}N and by varying the aluminum concentration y{sub Al}. The obtained results give a new degree of freedom in optoelectronic device applications such as optical fiber telecommunications operating at (1.55 μm)

44 CFR 15.5 - Preservation of property.

Science.gov (United States)

2010-10-01

... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Preservation of property. 15.5 Section 15.5 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT... NATIONAL EMERGENCY TRAINING CENTER § 15.5 Preservation of property. At both Mt. Weather and NETC we...

10 CFR 455.155 - Finality of decision.

Science.gov (United States)

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Finality of decision. 455.155 Section 455.155 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION GRANT PROGRAMS FOR SCHOOLS AND HOSPITALS AND BUILDINGS OWNED BY UNITS OF LOCAL GOVERNMENT AND PUBLIC CARE INSTITUTIONS Administrative Review § 455.155 Finality of...

First-Principle Study of the Optical Properties of Dilute-P GaN1-xPx Alloys.

Science.gov (United States)

Borovac, Damir; Tan, Chee-Keong; Tansu, Nelson

2018-04-16

An investigation on the optical properties of dilute-P GaN 1-x P x alloys by First-Principle Density Functional Theory (DFT) methods is presented, for phosphorus (P) content varying from 0% up to 12.5%. Findings on the imaginary and real part of the dielectric function are analyzed and the results are compared with previously reported theoretical works on GaN. The complex refractive index, normal-incidence reflectivity and birefringence are presented and a difference in the refractive index in the visible regime between GaN and GaNP alloys of ~0.3 can be engineered by adding minute amounts of phosphorus, indicating strong potential for refractive index tunability. The optical properties of the GaN 1-x P x alloys indicate their strong potential for implementation in various III-nitride-based photonic waveguide applications and Distributed Bragg Reflectors (DBR).

Computational study of GaAs1-xNx and GaN1-yAsy alloys and arsenic impurities in GaN

International Nuclear Information System (INIS)

Laaksonen, K; Komsa, H-P; Arola, E; Rantala, T T; Nieminen, R M

2006-01-01

We have studied the structural and electronic properties of As-rich GaAs 1-x N x and N-rich GaN 1-y As y alloys in a large composition range using first-principles methods. We have systematically investigated the effect of the impurity atom configuration near both GaAs and GaN sides of the concentration range on the total energies, lattice constants and bandgaps. The N (As) atoms, replacing substitutionally As (N) atoms in GaAs (GaN), cause the surrounding Ga atoms to relax inwards (outwards), making the Ga-N (Ga-As) bond length about 15% shorter (longer) than the corresponding Ga-As (Ga-N) bond length in GaAs (GaN). The total energies of the relaxed alloy supercells and the bandgaps experience large fluctuations within different configurations and these fluctuations grow stronger if the impurity concentration is increased. Substituting As atoms with N in GaAs induces modifications near the conduction band minimum, while substituting N atoms with As in GaN modifies the states near the valence band maximum. Both lead to bandgap reduction, which is at first rapid but later slows down. The relative size of the fluctuations is much larger in the case of GaAs 1-x N x alloys. We have also looked into the question of which substitutional site (Ga or N) As occupies in GaN. We find that under Ga-rich conditions arsenic prefers the substitutional N site over the Ga site within a large range of Fermi level values

21 CFR 155.172 - Canned dry peas.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Canned dry peas. 155.172 Section 155.172 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED VEGETABLES Requirements for Specific Standardized Canned Vegetables § 155.172 Canned dry...

Targeting miR-155 to Treat Experimental Scleroderma.

Science.gov (United States)

Yan, Qingran; Chen, Jie; Li, Wei; Bao, Chunde; Fu, Qiong

2016-02-01

Scleroderma is a refractory autoimmune skin fibrotic disorder. Alterations of microRNAs in lesional skin could be a new approach to treating the disease. Here, we found that expression of miR-155 was up regulated in lesional skin tissue from patients with either systemic or localized scleroderma, and correlated with fibrosis area. Then we demonstrated the potential of miR-155 as a therapeutic target in pre-clinical scleroderma models. MiR-155(-/-) mice were resistant to bleomycin induced skin fibrosis. Moreover, topical antagomiR-155 could effectively treat mice primed with subcutaneous bleomycin. In primary skin fibroblast, miR-155 silencing could inhibit collagen synthesis function, as well as signaling intensity of two pro-fibrotic pathways, Wnt/β-catenin and Akt, simultaneously. We further showed that miR-155 could regulate the two pathways via directly targeting casein kinase 1α (CK1α) and Src homology 2-containing inositol phosphatase-1 (SHIP-1), as previous reports. Mice with miR-155 knockout or topical antagomir-155 treatment showed inhibited Wnt/β-catenin and Akt signaling in skin upon bleomycin challenge. Together, our data suggest the potential of miR-155 silencing as a promising treatment for dermal fibrosis, especially in topical applications.

Ex situ n+ doping of GeSn alloys via non-equilibrium processing

Science.gov (United States)

Prucnal, S.; Berencén, Y.; Wang, M.; Rebohle, L.; Böttger, R.; Fischer, I. A.; Augel, L.; Oehme, M.; Schulze, J.; Voelskow, M.; Helm, M.; Skorupa, W.; Zhou, S.

2018-06-01

Full integration of Ge-based alloys like GeSn with complementary-metal-oxide-semiconductor technology would require the fabrication of p- and n-type doped regions for both planar and tri-dimensional device architectures which is challenging using in situ doping techniques. In this work, we report on the influence of ex situ doping on the structural, electrical and optical properties of GeSn alloys. n-type doping is realized by P implantation into GeSn alloy layers grown by molecular beam epitaxy (MBE) followed by flash lamp annealing. We show that effective carrier concentration of up to 1 × 1019 cm‑3 can be achieved without affecting the Sn distribution. Sn segregation at the surface accompanied with an Sn diffusion towards the crystalline/amorphous GeSn interface is found at P fluences higher than 3 × 1015 cm‑2 and electron concentration of about 4 × 1019 cm‑3. The optical and structural properties of ion-implanted GeSn layers are comparable with the in situ doped MBE grown layers.

Effect of N+Cr alloying on the microstructures and tensile properties of Hadfield steel

Energy Technology Data Exchange (ETDEWEB)

Chen, C. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Zhang, F.C., E-mail: zfc@ysu.edu.cn [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); National Engineering Research Center for Equipment and Technology of Cold Strip Rolling, Yanshan University, Qinhuangdao 066004 (China); Wang, F. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Liu, H.; Yu, B.D. [China Railway Shanhaiguan Bridge Group Co. LTD, Qinhuangdao 066205 (China)

2017-01-02

The microstructures and tensile behaviors of traditional Hadfield steel, named Mn12 steel, and Hadfield steel alloyed with N+Cr, named Mn12CrN steel were studied through optical microscopy, transmission electron microscopy, and scanning electron microscopy, among others. Three different tensile strain rates of 5×10{sup −4}, 5×10{sup −3}, and 5×10{sup −2} s{sup −1} were selected in the tensile test. The deformation microstructures and fracture morphologies of the two steels after fracture in the tensile test were observed to analyze the tensile deformation response to different tensile strain rates. Results showed that the grain size of Mn12CrN steel was evidently refined after alloying with N+Cr. The grain would not become abnormally coarse even with increasing austenitizing temperature. During tensile deformation, the strength and plasticity of Mn12CrN steel were superior to those of Mn12 steel at the same strain rate. With increasing the strain rate, the changes in strength and plasticity of Mn12CrN steel were less sensitive to tensile strain rate compared with Mn12 steel. The effects of grain refinement and N+Cr alloying on dynamic strain aging and deformation twining behaviors were responsible for this lack of sensitivity to strain rate.

14 CFR 406.155 - Offer of proof.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Offer of proof. 406.155 Section 406.155... Transportation Adjudications § 406.155 Offer of proof. A party whose evidence has been excluded by a ruling of the administrative law judge may offer the evidence for the record on appeal. ...

Investigating the optical modes of InxGa1xN alloy and In0.5Ga0.5N/GaN MQW in far-infrared reflectivity spectra

International Nuclear Information System (INIS)

Mirjalili, G.; Amraei, R.

2006-01-01

Optical properties of In x Ga 1 x N alloy and In 0 .5Ga 0 .5N/GaN multi quantum wells have been investigated in the region of far infrared. Far-IR reflectivity spectra of In 0 .5Ga 0 .5N/GaN multi quantum wells on GaAs substrate have been obtained by oblique incidence p- and s- polarization light using effective medium approximation. The spectra and the dielectric functions response give a good information about the phonon and plasmon contribution in doped MQW as well as the mole fraction of compounds in the alloys. The changes in position of optical modes are good tools for measurement of the amount of free carrier and the amount of mole fraction in the samples. During study of In x Ga 1 x N reflectivity spectra, two distinct reststrahl bands with frequency near those of pure InN and GaN were observed over entire composition range. Each band shifts to lower frequencies and decreases in amplitude as the concentration of corresponding compound in alloy decreased. Analysis of dielectric function gives the TO-like and LO-like mode frequencies. The changes in LO mode frequencies, due to coupling of phonon-plasmon, have been observed

On Ni/Au Alloyed Contacts to Mg-Doped GaN

Science.gov (United States)

Sarkar, Biplab; Reddy, Pramod; Klump, Andrew; Kaess, Felix; Rounds, Robert; Kirste, Ronny; Mita, Seiji; Kohn, Erhard; Collazo, Ramon; Sitar, Zlatko

2018-01-01

Ni/Au contacts to p-GaN were studied as a function of free hole concentration in GaN using planar transmission line measurement structures. All contacts showed a nonlinear behavior, which became stronger for lower doping concentrations. Electrical and structural analysis indicated that the current conduction between the contact and the p-GaN was through localized nano-sized clusters. Thus, the non-linear contact behavior can be well explained using the alloyed contact model. Two contributions to the contact resistance were identified: the spreading resistance in the semiconductor developed by the current crowding around the electrically active clusters, and diode-type behavior at the interface of the electrically active clusters with the semiconductor. Hence, the equivalent Ni/Au contact model consists of a diode and a resistor in series for each active cluster. The reduced barrier height observed in the measurements is thought to be generated by the extraction of Ga from the crystalline surface and localized formation of the Au:Ga phase. The alloyed contact analyses presented in this work are in good agreement with some of the commonly observed behavior of similar contacts described in the literature.

21 CFR 155.131 - Canned field corn.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Canned field corn. 155.131 Section 155.131 Food... Canned field corn. (a) Identity. (1) Canned field corn conforms to the definition and standard of... corn by § 155.130(a), except that the corn ingredient consists of succulent field corn or a mixture of...

Half Life Measurements in {sup 155}Gd

Energy Technology Data Exchange (ETDEWEB)

Malmskog, S G

1966-08-15

In the literature there exists a definite difference for the half life of the 86.5 keV level in Gd depending on whether {sup 155}Eu or {sup 155}Tb sources have been used. Using a good energy resolution electron-electron coincidence spectrometer and a {sup 155}Eu source, a half life of 6.48 {+-} 0.26 nsec was obtained for the 86.5 keV level. This is in agreement with the values previously measured with {sup 155}Tb sources. The half life of the 105.4 keV level was measured to be 1.12 {+-} 0.05 nsec.

Energy investigations on the mechanical properties of magnesium alloyed by X = C, B, N, O and vacancy

KAUST Repository

Wu, Xiaozhi

2013-10-25

The generalized stacking fault (GSF) energies and surface energies of magnesium and its alloys with alloying atoms X = C, B, N, O and vacancy have been investigated using the first-principles methods. It is found that the predominant reducing effects of the alloying atoms and vacancy on the stacking fault energy are resulted from the position of them in the 1st layer near the slip plane. The stacking fault energies are nearly the same as the pure magnesium while the alloying atoms and vacancy are placed in the 2nd, 3rd, 4th, 5th and 6th layers. It has been shown that O strongly reduces the GSF energy of Mg. The alloying atoms C, B and N increase the surface energy, but O and vacancy reduce the surface energy of Mg. The ductilities of Mg and Mg alloys have been discussed based on the Rice criterion by using the ratio between surface energy and unstable stacking fault energy. © 2013 Higher Education Press and Springer-Verlag Berlin Heidelberg.

Issues associated with the metalorganic chemical vapor deposition of ScGaN and YGaN alloys.

Energy Technology Data Exchange (ETDEWEB)

Koleske, Daniel David; Knapp, James Arthur; Lee, Stephen Roger; Crawford, Mary Hagerott; Creighton, James Randall; Cross, Karen Charlene; Thaler, Gerald

2009-07-01

The most energy efficient solid state white light source will likely be a combination of individually efficient red, green, and blue LED. For any multi-color approach to be successful the efficiency of deep green LEDs must be significantly improved. While traditional approaches to improve InGaN materials have yielded incremental success, we proposed a novel approach using group IIIA and IIIB nitride semiconductors to produce efficient green and high wavelength LEDs. To obtain longer wavelength LEDs in the nitrides, we attempted to combine scandium (Sc) and yttrium (Y) with gallium (Ga) to produce ScGaN and YGaN for the quantum well (QW) active regions. Based on linear extrapolation of the proposed bandgaps of ScN (2.15 eV), YN (0.8 eV) and GaN (3.4 eV), we expected that LEDs could be fabricated from the UV (410 nm) to the IR (1600 nm), and therefore cover all visible wavelengths. The growth of these novel alloys potentially provided several advantages over the more traditional InGaN QW regions including: higher growth temperatures more compatible with GaN growth, closer lattice matching to GaN, and reduced phase separation than is commonly observed in InGaN growth. One drawback to using ScGaN and YGaN films as the active regions in LEDs is that little research has been conducted on their growth, specifically, are there metalorganic precursors that are suitable for growth, are the bandgaps direct or indirect, can the materials be grown directly on GaN with a minimal defect formation, as well as other issues related to growth. The major impediment to the growth of ScGaN and YGaN alloys was the low volatility of metalorganic precursors. Despite this impediment some progress was made in incorporation of Sc and Y into GaN which is detailed in this report. Primarily, we were able to incorporate up to 5 x 10{sup 18} cm{sup -3} Y atoms into a GaN film, which are far below the alloy concentrations needed to evaluate the YGaN optical properties. After a no-cost extension was

Effect of natural aging on the properties of heat-treated A356 aluminum alloy

International Nuclear Information System (INIS)

Hernandez-Paz, J.F.; Paray, F.; Gruzleski, J.E.; Emadi, D.

2002-01-01

During the heat treatment of aluminum alloys, there is usually a delay time between quenching and the final artificial aging. This delay is called natural aging or preaging at room temperature. This research was conducted in order to study the effect of various natural aging times (0, 6, 12 and 20 hours) on the properties of unmodified and strontium modified A356 aluminum alloys solution heat-treated 4 hours at 540 o C, water quenched and artificially aged 6 hours at 155 o C and 170 o C. The samples were tested for electrical conductivity, microhardness, and tensile properties. In the case of the samples artificially aged at 155 o C from the results it can be seen a decrease in the microhardness and yield strength with natural aging. Regarding the samples aged at 170 o C it is noticed that natural aging at 12 hours will result in the lowest electrical conductivity, yield strength and microhardness. However, there is evidence of recovery of those properties at 20 hours of natural aging. Regarding the elongation, natural aging seems to have a positive effect when artificial aging is carried out at 155 o C, but at 170 o C an optimum elongation is obtained only at 12 hours. (author)

High pressure stability analysis and chemical bonding of Ti{sub 1-x}Zr{sub x}N alloy: A first principle study

Energy Technology Data Exchange (ETDEWEB)

Chauhan, Mamta; Gupta, Dinesh C., E-mail: sosfizix@gmail.com, E-mail: mamta-physics@yahoo.co.in [Condensed Matter Theory Group, School of Studies in Physics, Jiwaji University, Gwalior – 474 011 (India)

2016-05-23

First-principles pseudo-potential calculations have been performed to analyze the stability of Ti{sub 1-x}Zr{sub x}N alloy under high pressures. The first order phase transition from B1 to B2 phase has been observed in this alloy at high pressure. The variation of lattice parameter with the change in concentration of Zr atom in Ti{sub 1-x}Zr{sub x}N is also reported in both the phases. The calculations for density of states have been performed to understand the alloying effects on chemical bonding of Ti-Zr-N alloy.

Investigation of self-organized quantum dots in InGaN alloys for photovoltaic devices

Energy Technology Data Exchange (ETDEWEB)

Yuan, Jinshe; Wang, Mingyue [Chongqing Normal Univ. (China). Dept. of Physics

2008-07-01

The self-organized quantum dots in InGaN alloys grown by metal organic chemical vapor deposition for photovoltaic devices were investigated using photoluminescence spectra, x-ray diffraction and atomic force microscopy measurements. The AFM view of the alloy shows the island-like microstructure appearing to be composed of granular-crystalline in nanometer scale. By analysis of the PL, it has been found that the narrow 493nm emission peak with 490nm and 487nm shoulder peaks was originated from InGaN self-organized quantum dots, which provide a candidate for realizing high efficiencies photovoltaic devices. (orig.)

40 CFR 141.155 - Report delivery and recordkeeping.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Report delivery and recordkeeping. 141.155 Section 141.155 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Consumer Confidence Reports § 141.155...

40 CFR 155.52 - Stakeholder engagement.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Stakeholder engagement. 155.52 Section... REGISTRATION STANDARDS AND REGISTRATION REVIEW Registration Review Procedures § 155.52 Stakeholder engagement... Agency may meet with stakeholders regarding a forthcoming or ongoing registration review. For example...

Elastic and thermo-physical properties of TiC, TiN, and their intermediate composition alloys using ab initio calculations

International Nuclear Information System (INIS)

Kim, Jiwoong; Kang, Shinhoo

2012-01-01

Highlights: ► Elastic properties of TiC, TiN and their alloys were calculated by ab initio calculations. ► Debye temperature and Gruneisen constant of TiC, TiN and their alloys were calculated as a function of nitrogen content. ► Thermo-physical properties were calculated as a function of nitrogen content. ► Thermal expansion of the alloys was fitted in different temperature range. - Abstract: The equilibrium lattice parameters, elastic properties, material brittleness, heat capacities, and thermal expansion coefficients of TiC, TiN, and their intermediate composition alloys (Ti(C 1−x N x ), x = 0.25, 0.5, and 0.75) were calculated using ab initio density functional theory (DFT) methods. We employed the Debye–Gruneisen model to calculate a finite temperature heat capacity and thermal expansion coefficient. The calculated elastic moduli and thermal expansion coefficients agreed well with the experimental data and with other DFT calculations. Accurate heat capacities of TiC, TiN, and their intermediate composition alloys were obtained by calculating not only the phonon contributions but also the electron contributions to the heat capacity. Our calculations indicated that the heat capacity differences between each composition originated mainly from the electronic contributions.

Manufacturing and characterization of Ni-free N-containing ODS austenitic alloy

Science.gov (United States)

Mori, A.; Mamiya, H.; Ohnuma, M.; Ilavsky, J.; Ohishi, K.; Woźniak, Jarosław; Olszyna, A.; Watanabe, N.; Suzuki, J.; Kitazawa, H.; Lewandowska, M.

2018-04-01

Ni-free N-containing oxide dispersion strengthened (ODS) austenitic alloys were manufactured by mechanical alloying (MA) followed by spark plasma sintering (SPS). The phase evolutions during milling under a nitrogen atmosphere and after sintering were studied by X-ray diffraction (XRD). Transmission electron microcopy (TEM) and alloy contrast variation analysis (ACV), including small-angle neutron scattering (SANS) and ultra-small-angle X-ray scattering (USAXS), revealed the existence of nanoparticles with a diameter of 3-51 nm for the samples sintered at 950 °C. Sintering at 1000 °C for 5 and 15 min caused slight growth and a significant coarsening of the nanoparticles, up to 70 nm and 128 nm, respectively. The ACV analysis indicated the existence of two populations of Y2O3, ε-martensite and MnO. The dispersive X-ray spectrometry (EDS) confirmed two kinds of nanoparticles, Y2O3 and MnO. The material was characterized by superior micro-hardness, of above 500 HV0.1.

10 CFR 26.155 - Laboratory personnel.

Science.gov (United States)

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Laboratory personnel. 26.155 Section 26.155 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Laboratories Certified by the Department of Health and Human... ensure the continued competency of laboratory personnel by documenting their in-service training...

7 CFR 766.155 - Conflict with State law.

Science.gov (United States)

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Conflict with State law. 766.155 Section 766.155... AGRICULTURE SPECIAL PROGRAMS DIRECT LOAN SERVICING-SPECIAL Homestead Protection Program § 766.155 Conflict with State law. If there is a conflict between a borrower's homestead protection rights and any...

Electron mobility of two-dimensional electron gas in InGaN heterostructures: Effects of alloy disorder and random dipole scatterings

Science.gov (United States)

Hoshino, Tomoki; Mori, Nobuya

2018-04-01

InGaN has a smaller electron effective mass and is expected to be used as a channel material for high-electron-mobility transistors. However, it is an alloy semiconductor with a random distribution of atoms, which introduces additional scattering mechanisms: alloy disorder and random dipole scatterings. In this work, we calculate the electron mobility in InGaN- and GaN-channel high-electron-mobility transistors (HEMTs) while taking into account acoustic deformation potential, polar optical phonon, alloy disorder, and random dipole scatterings. For InGaN-channel HEMTs, we find that not only alloy disorder but also random dipole scattering has a strong impact on the electron mobility and it significantly decreases as the In mole fraction of the channel increases. Our calculation also shows that the channel thickness w dependence of the mobility is rather weak when w > 1 nm for In0.1Ga0.9N-channel HEMTs.

21 CFR 1314.155 - Suspension pending final order.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Suspension pending final order. 1314.155 Section 1314.155 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE RETAIL SALE OF SCHEDULED LISTED CHEMICAL PRODUCTS Order to Show Cause § 1314.155 Suspension pending final order. (a) The...

Crevice corrosion propagation on alloy 625 and alloy C276 in natural seawater

International Nuclear Information System (INIS)

McCafferty, E.; Bogar, F.D.; Thomas, E.D. II; Creegan, C.A.; Lucas, K.E.; Kaznoff, A.I.

1997-01-01

Chemical composition of the aqueous solution within crevices on two different Ni-Cr-Mo-Fe alloys immersed in natural seawater was determined using a semiquantitative thin-layer chromatographic method. Active crevices were found to contain concentrated amounts of dissolved Ni 2+ , Cr 3+ , Mo 3+ , and Fe 2+ ions. Propagation of crevice corrosion for the two alloys was determined from anodic polarization curves in model crevice solutions based upon stoichiometric dissolution or selective dissolution of alloy components. Both alloys 625 (UNS N06625) and C276 (UNS N10276) underwent crevice corrosion in the model crevice electrolytes. For the model crevice solution based upon selective dissolution of alloy constituents, the anodic dissolution rate for alloy 625 was higher than that for alloy C276. This trend was reversed for the model crevice solution based upon uniform dissolution of alloy constituents

Energy investigations on the mechanical properties of magnesium alloyed by X = C, B, N, O and vacancy

KAUST Repository

Wu, Xiaozhi; Liu, Lili; Wang, Rui; Gan, Liyong; Liu, Qing

2013-01-01

The generalized stacking fault (GSF) energies and surface energies of magnesium and its alloys with alloying atoms X = C, B, N, O and vacancy have been investigated using the first-principles methods. It is found that the predominant reducing

Ignition characteristics of the nickel-based alloy UNS N07001 in pressurized oxygen

Science.gov (United States)

Bransford, J. W.; Billiard, P. A.

1990-01-01

The development of ignition and combustion in pressurized oxygen atmospheres was studied for the nickel-based alloy UNS N07001. Ignition of the alloy was achieved by heating the top surface of a cylindrical specimen with a continuous-wave CO2 laser. Two heating procedures were used. In the first, laser power was adjusted to maintain an approximately linear increase in surface temperature. In the second, laser power was periodically increased until autoheating (self-heating) was established. It was found that the alloy would autoheat to combustion from temperatures below the solidus temperature. In addition, the alloy had a tendency to develop combustion zones (hot spots) at high oxygen pressures when the incremental (step) heating test mode was used. Unique points on the temperature-time curves that describe certain events are defined and the temperatures at which these events occur are given for the oxygen pressure range of 1.72 to 13.8 MPa (250 to 2000 psia).

29 CFR 1915.155 - Head protection.

Science.gov (United States)

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Head protection. 1915.155 Section 1915.155 Labor... helmets. (1) Head protection must comply with any of the following consensus standards: (i) ANSI Z89.1... as head protection devices that are constructed in accordance with one of the above consensus...

29 CFR 1917.155 - Air receivers.

Science.gov (United States)

2010-07-01

.... This section applies to compressed air receivers and equipment used for operations such as cleaning... transportation applications as railways, vehicles or cranes. (b) Gauges and valves. (1) Air receivers shall be... 29 Labor 7 2010-07-01 2010-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...

40 CFR 68.155 - Executive summary.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Executive summary. 68.155 Section 68...) CHEMICAL ACCIDENT PREVENTION PROVISIONS Risk Management Plan § 68.155 Executive summary. The owner or operator shall provide in the RMP an executive summary that includes a brief description of the following...

InN/GaN short-period superlattices as ordered InGaN ternary alloys

International Nuclear Information System (INIS)

Kusakabe, Kazuhide; Imai, Daichi; Wang, Ke; Yoshikawa, Akihiko

2016-01-01

Coherent (InN) 1 /(GaN) n short-period superlattices (SPSs) were successfully grown through dynamic atomic layer epitaxy (D-ALEp) mode by RF-plasma molecular beam epitaxy (MBE), where GaN layer thicknesses n were thinned down to 4 monolayer (ML). After this achievement, we demonstrated quasi-ternary InGaN behavior in their photoluminescence (PL) spectra for the first time. It was found interestingly that GaN layer thickness of n = 4 ML was the criterion both for structural control and continuum-band formation. Although highly lattice-mismatched InN/GaN interfaces easily introduce relaxation in (InN) 1 /(GaN) 4 SPSs during growth depending on the dynamic surface stoichiometry condition, this problem was overcome by precise control/removal of fluid-like residual In/Ga metals on the growth front with in-situ monitoring method. The (InN) 1 /(GaN) n SPSs with n ≥ 7 ML showed a constant PL peak energy around 3.2 eV at 12 K, reflecting discrete electron/hole wavefunctions. On the other hand, the (InN) 1 /(GaN) 4 SPSs indicated the red-shifted PL peak at 2.93 eV at 12 K, which was attributed to the continuum-band state with increasing in the overlap of electrons/hole wavefunctions. This result is concluded that the (InN) 1 /(GaN) 4 SPSs can be considered as ordered InGaN alloys. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Electrochemistry of Zn(II)/Zn on Mg alloy from the N-butyl-N-methylpyrrolidinium dicyanamide ionic liquid

Energy Technology Data Exchange (ETDEWEB)

Deng, Ming-Jay, E-mail: martinez730523@yahoo.com.tw [National Synchrotron Radiation Research Center, Hsinchu, Taiwan (China); Lin, Pei-Chiung [Department of Chemistry, National Cheng Kung University, Tainan, Taiwan (China); Chang, Jeng-Kuei, E-mail: jkchang@ncu.edu.tw [Institute of Materials Science and Engineering, National Central University, Taoyuan, Taiwan (China); Chen, Jin-Ming; Lu, Kueih-Tzu [National Synchrotron Radiation Research Center, Hsinchu, Taiwan (China)

2011-07-01

Highlights: > Electrodeposition of Zn was successfully demonstrnated in the water- and air-stable BMP-DCA ionic liquid. While ZnCl{sub 2} is insoluble in the BMP-TFSI ionic liquid, it dissolves easily in the BMP-DCA. > Amperometric titration experiments indicated that Zn(II) probably complexed as [Zn(DCA){sub 3}]- with DCA- anion. > Chronoamperometric experiments showed that the electrodeposition of Zn on GC and Mg alloy substrates involved 3D-instantaneous nucleation/growth process. > A lower deposition rate would bring out a more uniform and compact Zn coating layer (which is also thicker) and, consequently, this coating revealed a protection capability for the Mg substrate against corrosion. - Abstract: Electrochemical reaction of Zn(II)/Zn on glassy carbon electrode(GC) and Mg alloy substrates was investigated in the room-temperature ionic liquid, N-butyl-N-methyl-pyrrolidinium dicyanamide (BMP-DCA) containing ZnCl{sub 2} at 323 K. Amperometric titration experiments suggest that Zn(II) reacted with DCA anions forming [Zn(DCA){sub 3}]{sup -} complex anion, which also could be reduced to Zn metal via a single-step electron transfer process. By chronoamperometric measurements, the electrodeposition of Zn on GC and Mg alloy substrates involved three-dimensional instantaneous nucleation under diffusion control at 323 K. The Zn deposits are also systematically characterized by the techniques of powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The Zn layer deposited at a lower current density on Mg alloy substrates was more compact and uniform when compared to that deposited at a higher current density; consequently, this coating revealed a protection capability for the Mg substrate against corrosion.

Properties of hard alloys on the basis of WC-Co with the additives of nanodisperse TiN

International Nuclear Information System (INIS)

Ordanyan, S.S.; Andronova, T.E.; Vladimirova, M.A.; Pantelejev, I.B.; Zalite, I.

2001-01-01

The addition of nanodisperse titanium nitride (specific surface area of 20 - 30 m 2 /g, medium diameter of grains of 50 - 100 nm) to the starting hard alloy WC-Co in the stage of wet grinding allows to get some advantages: the growth of WC grains is retarded by the nanoparticles of TiN, being as a barrier for the process of secondary crystallization, and the toughness of hard alloy is being increased due to the formation of finely dispersed structure; the exploitation characteristics of cutting instruments are increased due to the volume alloying by means of titanium nitride having a decreased adhesion to the treated metal and decreased coefficient of friction; the formation of diffusion porosity is being eliminated due to the small size of TiN during the unavoidable dissolution of WC in TiN. (author)

MiR-155 induction by F. novicida but not the virulent F. tularensis results in SHIP down-regulation and enhanced pro-inflammatory cytokine response.

Directory of Open Access Journals (Sweden)

Thomas J Cremer

2009-12-01

Full Text Available The intracellular gram-negative bacterium Francisella tularensis causes the disease tularemia and is known for its ability to subvert host immune responses. Previous work from our laboratory identified the PI3K/Akt pathway and SHIP as critical modulators of host resistance to Francisella. Here, we show that SHIP expression is strongly down-regulated in monocytes and macrophages following infection with F. tularensis novicida (F.n.. To account for this negative regulation we explored the possibility that microRNAs (miRs that target SHIP may be induced during infection. There is one miR that is predicted to target SHIP, miR-155. We tested for induction and found that F.n. induced miR-155 both in primary monocytes/macrophages and in vivo. Using luciferase reporter assays we confirmed that miR-155 led to down-regulation of SHIP, showing that it specifically targets the SHIP 3'UTR. Further experiments showed that miR-155 and BIC, the gene that encodes miR-155, were induced as early as four hours post-infection in primary human monocytes. This expression was dependent on TLR2/MyD88 and did not require inflammasome activation. Importantly, miR-155 positively regulated pro-inflammatory cytokine release in human monocytes infected with Francisella. In sharp contrast, we found that the highly virulent type A SCHU S4 strain of Francisella tularensis (F.t. led to a significantly lower miR-155 response than the less virulent F.n. Hence, F.n. induces miR-155 expression and leads to down-regulation of SHIP, resulting in enhanced pro-inflammatory responses. However, impaired miR-155 induction by SCHU S4 may help explain the lack of both SHIP down-regulation and pro-inflammatory response and may account for the virulence of Type A Francisella.

AlN/GaN Digital Alloy for Mid- and Deep-Ultraviolet Optoelectronics.

Science.gov (United States)

Sun, Wei; Tan, Chee-Keong; Tansu, Nelson

2017-09-19

The AlN/GaN digital alloy (DA) is a superlattice-like nanostructure formed by stacking ultra-thin ( ≤ 4 monolayers) AlN barriers and GaN wells periodically. Here we performed a comprehensive study on the electronics and optoelectronics properties of the AlN/GaN DA for mid- and deep-ultraviolet (UV) applications. Our numerical analysis indicates significant miniband engineering in the AlN/GaN DA by tuning the thicknesses of AlN barriers and GaN wells, so that the effective energy gap can be engineered from ~3.97 eV to ~5.24 eV. The band structure calculation also shows that the valence subbands of the AlN/GaN DA is properly rearranged leading to the heavy-hole (HH) miniband being the top valence subband, which results in the desired transverse-electric polarized emission. Furthermore, our study reveals that the electron-hole wavefunction overlaps in the AlN/GaN DA structure can be remarkably enhanced up to 97% showing the great potential of improving the internal quantum efficiency for mid- and deep-UV device application. In addition, the optical absorption properties of the AlN/GaN DA are analyzed with wide spectral coverage and spectral tunability in mid- and deep-UV regime. Our findings suggest the potential of implementing the AlN/GaN DA as a promising active region design for high efficiency mid- and deep-UV device applications.

21 CFR 100.155 - Salt and iodized salt.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Salt and iodized salt. 100.155 Section 100.155 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION GENERAL Specific Administrative Rulings and Decisions § 100.155 Salt and iodized salt. (a) For the purposes of this section, the...

Investigation of the Self-Healing Behavior of Sn-Bi Metal Matrix Composite Reinforced with NiTi Shape Memory Alloy Strips Under Flexural Loading

Science.gov (United States)

Poormir, Mohammad Amin; Khalili, Seyed Mohammad Reza; Eslami-Farsani, Reza

2018-06-01

Utilizing intelligent materials such as shape memory alloys as reinforcement in metal matrix composites is a novel method to mimic self-healing behavior. In this study, the bending behavior of a self-healing metal matrix composite made from Sn-13 wt.% Bi alloy as matrix and NiTi shape memory alloy (SMA) strips as reinforcement is investigated. Specimens were fabricated in different reinforcement vol.% (0.78, 1.55, 2.33) and in various pre-strains (0, 2, 6%) and were healed at three healing temperatures (170°C, 180°C, 190°C). Results showed that shape recovery was accomplished in all the specimens, but not all of them were able to withstand second loading after healing. Only specimens with 2.33 vol.% of SMA strips, 1.55 vol.% of SMA, and 6% pre-strain could endure bending force after healing, and they gained 35.31-51.83% of bending force self-healing efficiency.

Effect of Nb on magnetic and mechanical properties of TbDyFe alloys

Science.gov (United States)

Wang, Naijuan; Liu, Yuan; Zhang, Huawei; Chen, Xiang; Li, Yanxiang

2018-03-01

The intrinsic brittleness in giant magnetostrictive material TbDyFe alloy has devastating influence on the machinability and properties of the alloy, thus affecting its applications. The purpose of this paper is to study the mechanical properties of the TbDyFe alloy by alloying with Nb element. The samples (Tb0.3Dy0.7)xFe2xNby (y = 0, 0.01, 0.04, 0.07, 0.1; 3x + y = 1) were melted in an arc melting furnace under high purity argon atmosphere. The microstructure, magnetostrictive properties and mechanical performance of the alloys were studied systematically. The results showed that NbFe2 phases were observed in the alloys with the addition of Nb. Moreover, both the NbFe2 phases and rare earth (RE)-rich phases were increased with the increasing of Nb element. The mechanical properties results revealed that the fracture toughness of the alloy with the addition of Nb enhanced 1.5-5 times of the Nb-free alloy. Both the NbFe2 phase and the RE-rich phase had the ability to prevent crack propagation, so that they can strengthen the REFe2 body. However, NbFe2 phase is a paramagnetic phase, which can reduce the magnetostrictive properties of the alloy by excessive precipitation.

Influence of additives on the microstructure and tensile properties of near-eutectic Al-10.8%Si cast alloy

International Nuclear Information System (INIS)

Mohamed, A.M.A.; Samuel, A.M.; Samuel, F.H.; Doty, H.W.

2009-01-01

The continuing quest for aluminum castings with enhanced mechanical properties for applications in the automotive industries has intensified the interest in aluminum-silicon alloys. In Al-Si alloys, the properties are influenced by the shape and distribution of the eutectic silicon particles in the matrix, as also by the iron intermetallics and copper phases that occur upon solidification. The detailed microstructure and tensile properties of as-cast and heat-treated new experimental alloy belonging to cast Al-Si near-eutectic alloys have been investigated as a function of Fe, Mn, Cu, and Mg content. Microstructural examination was carried out using optical microscopy, image analysis, and electron probe microanalysis (EPMA), wavelength dispersive spectroscopic (WDS) analysis facilities. Tensile properties upon artificial aging in the temperature range of 155-240 o C for 5 h were also investigated. The results show that the volume fraction of Fe-intermetallics increases as the iron or manganese contents increase. Compact polygonal or star-like particles form when the sludge factor is greater than 2.1. The Al 2 Cu phase was observed to dissolve almost completely during solution heat treatment of all the alloys studied, especially those containing high levels of Mg and Fe, while Al 5 Cu 2 Mg 8 Si 6 , sludge, and α-Fe phases were found to persist after solution heat treatment. The β-Al 5 (Fe,Mn)Si phase dissolved partially in Sr-modified alloys, and its dissolution became more pronounced after solution heat treatment. At 0.5% Mn, the β-Fe phase forms when the Fe content is above 0.75%, causing the tensile properties to decrease drastically. The same results are obtained when the levels of both Fe and Mn are increased beyond 0.75%, because of sludge formation. On the other hand, the tensile properties of the Cu-containing alloys are affected slightly at high levels of Mg as a result of the formation of Al 5 Cu 2 Mg 8 Si 6 which decreases the amount of free Mg

Ni.sub.3 Al-based intermetallic alloys having improved strength above 850.degree. C.

Science.gov (United States)

Liu, Chain T.

2000-01-01

Intermetallic alloys composed essentially of: 15.5% to 17.0% Al, 3.5% to 5.5% Mo, 4% to 8% Cr, 0.04% to 0.2% Zr, 0.04% to 1.5% B, balance Ni, are characterized by melting points above 1200.degree. C. and superior strengths at temperatures above 1000.degree. C.

Superconducting single-photon detectors designed for operation at 1.55-μm telecommunication wavelength

International Nuclear Information System (INIS)

Milostnaya, I; Korneev, A; Rubtsova, I; Seleznev, V; Minaeva, O; Chulkova, G; Okunev, O; Voronov, B; Smirnov, K; Gol'tsman, G; Slysz, W; Wegrzecki, M; Guziewicz, M; Bar, J; Gorska, M; Pearlman, A; Kitaygorsky, J; Cross, A; Sobolewski, Roman

2006-01-01

We report on our progress in development of superconducting single-photon detectors (SSPDs), specifically designed for secure high-speed quantum communications. The SSPDs consist of NbN-based meander nanostructures and operate at liquid helium temperatures. In general, our devices are capable of GHz-rate photon counting in a spectral range from visible light to mid-infrared. The device jitter is 18 ps and dark counts can reach negligibly small levels. The quantum efficiency (QE) of our best SSPDs for visible-light photons approaches a saturation level of ∼30-40%, which is limited by the NbN film absorption. For the infrared range (1.55μm), QE is ∼6% at 4.2 K, but it can be significantly improved by reduction of the operation temperature to the 2-K level, when QE reaches ∼20% for 1.55-μm photons. In order to further enhance the SSPD efficiency at the wavelength of 1.55 μm, we have integrated our detectors with optical cavities, aiming to increase the effective interaction of the photon with the superconducting meander and, therefore, increase the QE. A successful effort was made to fabricate an advanced SSPD structure with an optical microcavity optimized for absorption of 1.55 μm photons. The design consisted of a quarter-wave dielectric layer, combined with a metallic mirror. Early tests performed on relatively low-QE devices integrated with microcavities, showed that the QE value at the resonator maximum (1.55-μm wavelength) was of the factor 3-to-4 higher than that for a nonresonant SSPD. Independently, we have successfully coupled our SSPDs to single-mode optical fibers. The completed receivers, inserted into a liquid-helium transport dewar, reached ∼1% system QE for 1.55 μm photons. The SSPD receivers that are fiber-coupled and, simultaneously, integrated with resonators are expected to be the ultimate photon counters for optical quantum communications

Melatonin inhibits proliferation and invasion via repression of miRNA-155 in glioma cells.

Science.gov (United States)

Gu, Junyi; Lu, Zhongsheng; Ji, Chenghong; Chen, Yuchao; Liu, Yuzhao; Lei, Zhe; Wang, Longqiang; Zhang, Hong-Tao; Li, Xiangdong

2017-09-01

Melatonin, an indolamine mostly synthesized in the pineal gland, exerts the anti-cancer effect by various mechanisms in glioma cells. Our previous study showed that miR-155 promoted glioma cell proliferation and invasion. However, the question of whether melatonin may inhibit glioma by regulating miRNAs has not yet been addressed. In this study, we found that melatonin (100μM, 1μM and 1nM) significantly inhibited the expression of miR-155 in human glioma cell lines U87, U373 and U251. Especially, the lowest expression of miR-155 was detected in 1μM melatonin-treated glioma cells. Melatonin (1μM) inhibits cell proliferation of U87 by promoting cell apoptosis. Nevertheless, melatonin had no effect on cell cycle distribution of U87 cells. Moreover, U87 cells treated with 1μM melatonin presented significantly lower migration and invasion ability when compared with control cells. Importantly, melatonin inhibited c-MYB expression, and c-MYB knockdown reduced miR-155 expression and migration and invasion in U87 cells. Taken together, for the first time, our findings show that melatonin inhibits miR-155 expression and thereby represses glioma cell proliferation, migration and invasion, and suggest that melatonin may downregulate the expression of miR-155 via repression of c-MYB. This will provide a theoretical basis for revealing the anti-glioma mechanisms of melatonin. Copyright © 2017. Published by Elsevier Masson SAS.

Optical characterization of In xGa1-xN alloys

International Nuclear Information System (INIS)

Gartner, M.; Kruse, C.; Modreanu, M.; Tausendfreund, A.; Roder, C.; Hommel, D.

2006-01-01

InGaN layers were grown by molecular beam epitaxy (MBE) either directly on (0 0 0 1) sapphire substrates or on GaN-template layers deposited by metal-organic vapor-phase epitaxy (MOVPE). We combined spectroscopic ellipsometry (SE), Raman spectroscopy (RS), photoluminescence (PL) and atomic force microscopy (AFM) measurements to investigate optical properties, microstructure, vibrational and mechanical properties of the InGaN/GaN/sapphire layers. The analysis of SE data was done using a parametric dielectric function model, established by in situ and ex situ measurements. A dielectric function database, optical band gap, the microstructure and the alloy composition of the layers were derived. The variation of the InGaN band gap with the In content (x) in the 0 g = 3.44-4.5x. The purity and the stability of the GaN and InGaN crystalline phase were investigated by RS

17 CFR 155.4 - Trading standards for introducing brokers.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Trading standards for introducing brokers. 155.4 Section 155.4 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION TRADING STANDARDS § 155.4 Trading standards for introducing brokers. (a) Each introducing broker...

Europium-155 in Debris from Nuclear Weapons

DEFF Research Database (Denmark)

Aarkrog, Asker; Lippert, Jørgen Emil

1967-01-01

The lithium-drifted germanium detector enables determination of europium-155 on a routine basis in environmental samples contaminated with debris from nuclear weapons. From measurements of europium-155, cesium-144, and strontium-90 in air filters collected between 1961 and 1966, the yield...

14 CFR 23.155 - Elevator control force in maneuvers.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Elevator control force in maneuvers. 23.155 Section 23.155 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Controllability and Maneuverability § 23.155 Elevator control force in maneuvers. (a) The elevator control force...

First realisation of a labelling kit of N.T.P. 15-5 ligand by {sup 99m}Tc in view of a clinical application in cartilage functional imaging; Premiere realisation d'une trousse de marquage du ligand NTP 15-5 par le 99mTc en vue d'une application clinique en imagerie fonctionnelle du cartilage

Energy Technology Data Exchange (ETDEWEB)

Miot-Noirault, E.; Cachin, F.; Vidal, A.; Auzeloux, P.; Chezal, J.M.; Gaumet, V.; Askienazy, S. [Inserm, EA4231, UMR 990, 63 - Clermont-Ferrand (France); Guenu, S. [UFR de pharmacie, laboratoire de chimie analytique, 63 - Clermont-Ferrand (France); Askienazy, S. [Laboratoires Cyclopharma, 63 - Saint-Beauzire (France)

2010-07-01

We are working on a SPECT tracer for functional imaging of articular cartilage, the {sup 99m}Tc-NTP 15-5. This molecule has its application in degenerative diseases of cartilage (arthrosis, arthritis and chondrosarcoma). Excellent reports of cartilage versus tissues fixing ratios are obtained in different animal models as well as human anatomical parts. For clinical application, we present the development of a labelling kit by the technetium of the ligand NTP 15-5. (N.C.)

Coercivity Recovery Effect of Sm-Fe-Cu-Al Alloy on Sm2Fe17N3 Magnet

Science.gov (United States)

Otogawa, Kohei; Asahi, Toru; Jinno, Miho; Yamaguchi, Wataru; Takagi, Kenta; Kwon, Hansang

2018-03-01

The potential of a Sm-Fe-Cu-Al binder for improvement of the magnetic properties of Sm2Fe17N3 was examined. Transmission electron microscope (TEM) observation of a Sm-Fe-Cu-Al alloy-bonded Sm2Fe17N3 magnet which showed high coercivity revealed that the Sm-Fe-Cu-Al alloy had an effect of removing the surface oxide layer of the Sm2 Fe17N3 grains. However, the Sm-Fe-Cu-Al binder was contaminated by carbon and nitrogen, which originated from the organic solvent used as the milling medium during pulverization. To prevent carbon and nitrogen contamination, the Sm-Fe- Cu-Al alloy was added directly on the surface of the Sm2Fe17N3 grains by sputtering. Comparing the recovered coercivity per unit amount of the added binder the uncontaminated binder-coated sample had a higher coercivity recovery effect than the milled binder-added sample. These results suggested that sufficient addition of the contamination-free Sm-Fe-Cu-Al binder has the possibility to reduce the amount of binder necessary to produce a high coercive Sm2Fe17N3 magnet.

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...

Effects of TiN coating on the corrosion of nanostructured Ti-30Ta-xZr alloys for dental implants

Science.gov (United States)

Kim, Won-Gi; Choe, Han-Cheol

2012-01-01

Electrochemical characteristics of a titanium nitride (TiN)-coated/nanotube-formed Ti-Ta-Zr alloy for biomaterials have been researched by using the magnetic sputter and electrochemical methods. Ti-30Ta-xZr (x = 3, 7 and 15 wt%) alloys were prepared by arc melting and heat treated for 24 h at 1000 °C in an argon atmosphere and then water quenching. The formation of oxide nanotubes was achieved by anodizing a Ti-30Ta-xZr alloy in H3PO4 electrolytes containing small amounts of fluoride ions at room temperature. Anodization was carried out using a scanning potentiostat, and all experiments were conducted at room temperature. The microstructure and morphology of nanotube arrays were characterized by optical microscopy (OM), field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). The TiN coatings were obtained by the radio-frequency (RF) magnetron sputtering technique. The depositions were performed from pure Ti targets on Ti-30Ta-xZr alloys substrates. The corrosion properties of the specimens were examined using potentiodynamic test in a 0.9% NaCl solution by using potentiostat. The microstructures of Ti-30Ta-xZr alloys were changed from an equiaxed to a needle-like structure with increasing Zr content. The interspace between the nanotubes was approximately 20, 80 and 200 nm for Zr contents of 3, 7 and 15 wt%, respectively. The corrosion resistance of the TiN-coated on the anodized Ti-30Ta-xZr alloys was higher than that of the untreated Ti alloys, indicating a better protective effect.

Thermal Plasma Spheroidization of High-Nitrogen Stainless Steel Powder Alloys Synthesized by Mechanical Alloying

Science.gov (United States)

Razumov, Nikolay G.; Popovich, Anatoly A.; Wang, QingSheng

2018-03-01

This paper presents the results of experimental studies on the treatment of Fe-23Cr-11Mn-1N high-nitrogen stainless steel powder alloys, synthesized by the mechanical alloying (MA) of elemental powders in the flow of a thermal plasma. Fe-23Cr-11Mn-1N high-nitrogen stainless steel powder alloys were prepared by MA in the attritor under an argon atmosphere. For spheroidization of Fe-23Cr-11Mn-1N high-nitrogen stainless steel powder alloys, the TekSphero 15 plant manufactured by Tekna Plasma Systems Inc was used. The studies have shown the possibility of obtaining Fe-23Cr-11Mn-1N high-nitrogen spherical powders steel alloys from the powder obtained by MA. According to the results of a series of experiments, it was found that the results of plasma spheroidization of powders essentially depend on the size of the fraction due to some difference in the particle shape and flowability, and on the gas regime of the plasma torch. It is established that during the plasma spheroidization process, some of the nitrogen leaves the alloy. The loss rate of nitrogen depends on the size of the initial particles.

On the corrosion testing of weldments of high alloyed CrNiMo-stainless steels and NiCrMo-alloys

International Nuclear Information System (INIS)

Riedel, G.; Voigt, C.; Werner, H.

1997-01-01

Weldments of high-alloyed CrNiMo stainless steels and NiCrMo alloys can be more susceptible to localized corrosion than the solution annealed basic material owing to segregations and precipitations in the heat affected zone, the high temperature zone and/or in the weld. To investigate these differences the FeCl 3 -test (10% FeCl 3 . 6aq), the test ''green death'' (11.5% H 2 SO 4 , 1.2% HCl, 1% CuCl 2 , 1% FeCl 3 ) as well as chronopotentiostatic tests in artificial sea water or in 3% NaCl-solution are used. In particular for testing the highest alloyed materials a CaCl 2 -test was developed (4.5 M CaCl 2 , chronopotentiostatic test in duration of 8 to 10 hours at + 200 mV (SCE)), which can be carried out to a temperature of 115 C at atmospheric pressure. The aggressivity increases in the range FeCl 3 -test, ''green death''-test, CaCl 2 -test. Matching and graduated over-alloyed weldments (TIG, heat input of 7 and 15.5 kJ/cm) of materials 1.4529, 1.4562, 2.4856, 2.4819 (german materials No.) are comparingly examined in various tests, of materials 1.4406, 1.4539, 1.4439 and 1.4563 (german materials No.) only matching weldments in the FeCl 3 -test. In strongly oxidizing media only a highly over-alloyed performed weldment (filler material 2.4607, german material No.) produces the best corrosion behaviour, measured as the critical temperatures of localized corrosion. Measurements of critical current densities of passivation can be used for investigations of corrosion behaviour of weldments, too. Critical current densities of passivation are showing a tendency to inverse proportion to the critical temperatures of localized corrosion. Suitable electrolytes are among others 0.2 M H 2 SO 4 + 1 M NaCl + 10 -3 % KSCN, N 2 -bubbled, 25 to 60 C and xM H 2 SO 4 + 4 M NaCl + 10 -3 % KSCN (x = 0.05 to 1), 25 C, in contact with air. An influence of heat input at the welding is indicated in the test of localized corrosion, but it is only small. It is sometimes more clearly shown at

20 CFR 401.155 - Law enforcement purposes.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Law enforcement purposes. 401.155 Section 401... INFORMATION Disclosure of Official Records and Information § 401.155 Law enforcement purposes. (a) General. The Privacy Act allows us to disclose information for law enforcement purposes under certain...

24 CFR 983.155 - Completion of housing.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Completion of housing. 983.155 Section 983.155 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR PUBLIC AND INDIAN HOUSING, DEPARTMENT OF HOUSING AND URBAN...

24 CFR 990.155 - Addition and deletion of units.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Addition and deletion of units. 990.155 Section 990.155 Housing and Urban Development Regulations Relating to Housing and Urban...; Computation of Eligible Unit Months § 990.155 Addition and deletion of units. (a) Changes in public housing...

Optical characterization of In xGa 1- xN alloys

Science.gov (United States)

Gartner, M.; Kruse, C.; Modreanu, M.; Tausendfreund, A.; Roder, C.; Hommel, D.

2006-10-01

InGaN layers were grown by molecular beam epitaxy (MBE) either directly on (0 0 0 1) sapphire substrates or on GaN-template layers deposited by metal-organic vapor-phase epitaxy (MOVPE). We combined spectroscopic ellipsometry (SE), Raman spectroscopy (RS), photoluminescence (PL) and atomic force microscopy (AFM) measurements to investigate optical properties, microstructure, vibrational and mechanical properties of the InGaN/GaN/sapphire layers. The analysis of SE data was done using a parametric dielectric function model, established by in situ and ex situ measurements. A dielectric function database, optical band gap, the microstructure and the alloy composition of the layers were derived. The variation of the InGaN band gap with the In content ( x) in the 0 < x ≤ 0.14 range was found to follow the linear law Eg = 3.44-4.5 x. The purity and the stability of the GaN and InGaN crystalline phase were investigated by RS.

The structural properties of InGaN alloys and the interdependence on the thermoelectric behavior

Science.gov (United States)

Kucukgok, Bahadir; Wu, Xuewang; Wang, Xiaojia; Liu, Zhiqiang; Ferguson, Ian T.; Lu, Na

2016-02-01

The III-Nitrides are promising candidate for high efficiency thermoelectric (TE) materials and devices due to their unique features which includes high thermal stability. A systematic study of the room temperature TE properties of metalorganic chemical vapor deposition grown InxGa1-xN were investigated for x = 0.07 to 0.24. This paper investigated the role of indium composition on the TE properties of InGaN alloys in particular the structural properties for homogenous material that did not show significant phase separation. The highest Seebeck and power factor values of 507 μV K-1 and 21.84 × 10-4 Wm-1K-1 were observed, respectively for In0.07Ga0.93N at room temperature. The highest value of figure-of-merit (ZT) was calculated to be 0.072 for In0.20Ga0.80N alloy at room temperature.

The dependence of activity coefficient on intensive thermodynamic parameters in a liquid Fe-N-V alloy

Energy Technology Data Exchange (ETDEWEB)

Hutny, A.; Siwka, J. [Faculty of Materials Processing Technology and Applied Physics, Technical Univ. of Czestochowa (Poland)

2003-07-01

The article presents the methodology and results of experimental studies on the solubility of nitrogen in liquid Fe-V alloys. Tests were carried out using the levitation metal melting technique. Liquid alloys of Fe-V ([%V]{sub wt.%} 1.5; 2.5; 4,0; 5.8; 7.8; 12.2; 45%) were saturated with nitrogen at temperatures of 2073, 2173, 2273 K. The partial pressure of nitrogen was varied in the range 0.001-2.5 MPa. The experiment involved melting a 1 g specimen in an electromagnetic field generated by a levitation coil, filling the reaction chamber with nitrogen up to the required pressure and heating the specimen up to a preset temperature. High nitrogen concentrations were obtained in the samples due to the formation of high nitrogen partial pressures in the gaseous phase in the reaction chamber. In such conditions, all interactions of nitrogen in the alloy tested could be disclosed, namely: nitrogen-vanadium, nitrogen-nitrogen, and nitrogen-nitrogen-vanadium interactions. The results of the tests showed a nonlinear dependence of the activity coefficient, f{sub N}, not only on vanadium content in the alloy, but also on nitrogen content in it. Using the experimental data and the findings of the previous study on the liquid Fe-N alloy, temperature relationships of inter- and self-reaction parameters have been determined. (orig.)

Loss of heterozygosity on chromosome 11p15.5 and relapse in hepatoblastomas.

Science.gov (United States)

Chitragar, S; Iyer, V K; Agarwala, S; Gupta, S D; Sharma, A; Wari, M N

2011-01-01

IGF2 is a tumor suppressor gene at locus 11p15. Many hepatoblastomas have loss of heterozygosity (LOH) at this locus. Earlier studies have not demonstrated any association between LOH and prognosis. Aim of the study was to evaluate the prognostic significance of LOH at 11p15.5 in hepatoblastomas. DNA was isolated from normal liver and tumor tissue in 20 patients with hepatoblastoma. PCR was performed and cases were classified as LOH present, absent or non-informative. Patients' follow-up data was analyzed using Fischer's exact test and Kaplan-Meier survival analysis for relapse-free survival (RFS) in relation to LOH. Ethical clearance was obtained from the institutional ethics board. All cases were informative for at least one microsatellite marker used. 4 of the 20 cases (20%) had LOH at 11p15.5. One patient died in the immediate postoperative period. 5 of 19 patients relapsed (26%). Of 4 patients who had LOH, 3 (75%) relapsed, the time to relapse being 7, 7 and 9 months, respectively. Of the 15 cases without LOH, 2 (13.3%) relapsed. 4 patients had mixed epithelial and mesenchymal histology; 3 of them had LOH. The 2 groups with and without LOH were well matched. The RFS for patients with LOH (n=4) was 13% (mean survival time [MST]: 8.7 months; 95CI 6.7-10.7), while the RFS for cases without LOH (n=15) was 75% (MST: 100.7 months; 95CI 74.5-126.8). Mixed epithelial and mesenchymal histology is more frequently associated with LOH on chromosome 11p15.5 than pure epithelial histology. LOH on chromosome 11p15.5 is associated with a significantly increased incidence of relapse and a significantly shorter relapse-free survival in patients with hepatoblastoma. The risk of relapse is higher and the RFS lower both in standard-risk and high-risk patients with hepatoblastoma if they demonstrate the presence of LOH at 11p15.5. © Georg Thieme Verlag KG Stuttgart · New York.

Independent determination of In and N concentrations in GaInNAs alloys

International Nuclear Information System (INIS)

Lu, W; Lim, J J; Bull, S; Andrianov, A V; Larkins, E C; Staddon, C; Foxon, C T; Sadeghi, M; Wang, S M; Larsson, A

2009-01-01

High-resolution x-ray diffraction (HRXRD) and photoreflectance (PR) spectroscopy were used to independently determine the In and N concentrations in GaInNAs alloys grown by solid-source molecular beam epitaxy (SSMBE). The lattice constant and bandgap energy can be expressed as two independent equations in terms of the In and N concentrations, respectively. The HRXRD measurement provided the lattice constant and the PR measurement extracted the bandgap energy. By simultaneously solving these two equations, we have determined the In and N concentrations with the error as small as 0.001

In-beam gamma spectroscopy of 155Tm

International Nuclear Information System (INIS)

Raut, R.; Ganguly, S.; Kshetri, R.; Banerjee, P.; Bhattacharya, S.; Mukherjee, A.; Saha Sarkar, M.; Goswami, A.; Bhowal, S.; Ganguly, G.; Muralithar, S.; Singh, R.P.

2005-01-01

The observation of superdeformation in 154 Er has pronounced the possibility of observation of high spin phenomena in the neighbouring isotones. There has been a paucity of data on 155 Tm till day. The present work proposes to extend the level scheme of 155 Tm and thus established the systematics therein

30 CFR 206.155 - Accounting for comparison.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Accounting for comparison. 206.155 Section 206... MANAGEMENT PRODUCT VALUATION Federal Gas § 206.155 Accounting for comparison. (a) Except as provided in... the gas the residue gas is not sold pursuant to an arm's-length contract, the value, for royalty...

Microstructure and mechanical properties of thermoelectric nanostructured n-type silicon-germanium alloys synthesized employing spark plasma sintering

Energy Technology Data Exchange (ETDEWEB)

Bathula, Sivaiah [CSIR-Network of Institutes for Solar Energy, CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012 (India); Department of Applied Physics, Delhi Technological University, Delhi (India); Gahtori, Bhasker; Tripathy, S. K.; Tyagi, Kriti; Srivastava, A. K.; Dhar, Ajay, E-mail: adhar@nplindia.org [CSIR-Network of Institutes for Solar Energy, CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012 (India); Jayasimhadri, M. [Department of Applied Physics, Delhi Technological University, Delhi (India)

2014-08-11

Owing to their high thermoelectric (TE) figure-of-merit, nanostructured Si{sub 80}Ge{sub 20} alloys are evolving as a potential replacement for their bulk counterparts in designing efficient radio-isotope TE generators. However, as the mechanical properties of these alloys are equally important in order to avoid in-service catastrophic failure of their TE modules, we report the strength, hardness, fracture toughness, and thermal shock resistance of nanostructured n-type Si{sub 80}Ge{sub 20} alloys synthesized employing spark plasma sintering of mechanically alloyed nanopowders of its constituent elements. These mechanical properties show a significant enhancement, which has been correlated with the microstructural features at nano-scale, delineated by transmission electron microscopy.

Reducing Mg acceptor activation-energy in Al(0.83)Ga(0.17)N disorder alloy substituted by nanoscale (AlN)₅/(GaN)₁ superlattice using Mg(Ga) δ-doping: Mg local-structure effect.

Science.gov (United States)

Zhong, Hong-xia; Shi, Jun-jie; Zhang, Min; Jiang, Xin-he; Huang, Pu; Ding, Yi-min

2014-10-23

Improving p-type doping efficiency in Al-rich AlGaN alloys is a worldwide problem for the realization of AlGaN-based deep ultraviolet optoelectronic devices. In order to solve this problem, we calculate Mg acceptor activation energy and investigate its relationship with Mg local structure in nanoscale (AlN)5/(GaN)1 superlattice (SL), a substitution for Al(0.83)Ga(0.17)N disorder alloy, using first-principles calculations. A universal picture to reduce acceptor activation energy in wide-gap semiconductors is given for the first time. By reducing the volume of the acceptor local structure slightly, its activation energy can be decreased remarkably. Our results show that Mg acceptor activation energy can be reduced significantly from 0.44 eV in Al(0.83)Ga(0.17)N disorder alloy to 0.26 eV, very close to the Mg acceptor activation energy in GaN, and a high hole concentration in the order of 10(19) cm(-3) can be obtained in (AlN)5/(GaN)1 SL by Mg(Ga) δ-doping owing to GaN-monolayer modulation. We thus open up a new way to reduce Mg acceptor activation energy and increase hole concentration in Al-rich AlGaN.

Reducing Mg Acceptor Activation-Energy in Al0.83Ga0.17N Disorder Alloy Substituted by Nanoscale (AlN)5/(GaN)1 Superlattice Using MgGa δ-Doping: Mg Local-Structure Effect

Science.gov (United States)

Zhong, Hong-Xia; Shi, Jun-Jie; Zhang, Min; Jiang, Xin-He; Huang, Pu; Ding, Yi-Min

2014-10-01

Improving p-type doping efficiency in Al-rich AlGaN alloys is a worldwide problem for the realization of AlGaN-based deep ultraviolet optoelectronic devices. In order to solve this problem, we calculate Mg acceptor activation energy and investigate its relationship with Mg local structure in nanoscale (AlN)5/(GaN)1 superlattice (SL), a substitution for Al0.83Ga0.17N disorder alloy, using first-principles calculations. A universal picture to reduce acceptor activation energy in wide-gap semiconductors is given for the first time. By reducing the volume of the acceptor local structure slightly, its activation energy can be decreased remarkably. Our results show that Mg acceptor activation energy can be reduced significantly from 0.44 eV in Al0.83Ga0.17N disorder alloy to 0.26 eV, very close to the Mg acceptor activation energy in GaN, and a high hole concentration in the order of 1019 cm-3 can be obtained in (AlN)5/(GaN)1 SL by MgGa δ-doping owing to GaN-monolayer modulation. We thus open up a new way to reduce Mg acceptor activation energy and increase hole concentration in Al-rich AlGaN.

The structural properties of InGaN alloys and the interdependence on the thermoelectric behavior

Directory of Open Access Journals (Sweden)

Bahadir Kucukgok

2016-02-01

Full Text Available The III-Nitrides are promising candidate for high efficiency thermoelectric (TE materials and devices due to their unique features which includes high thermal stability. A systematic study of the room temperature TE properties of metalorganic chemical vapor deposition grown InxGa1-xN were investigated for x =  0.07 to 0.24. This paper investigated the role of indium composition on the TE properties of InGaN alloys in particular the structural properties for homogenous material that did not show significant phase separation. The highest Seebeck and power factor values of 507 μV K−1 and 21.84 × 10−4 Wm−1K−1 were observed, respectively for In0.07Ga0.93N at room temperature. The highest value of figure-of-merit (ZT was calculated to be 0.072 for In0.20Ga0.80N alloy at room temperature.

The structural properties of InGaN alloys and the interdependence on the thermoelectric behavior

Energy Technology Data Exchange (ETDEWEB)

Kucukgok, Bahadir; Lu, Na, E-mail: Luna@purdue.edu [Lyles School of Civil Engineering, Purdue University, West Lafayette, IN 47907 (United States); Wu, Xuewang; Wang, Xiaojia [Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN 55455 (United States); Liu, Zhiqiang [Institute of Semiconductors, Chinese Academy of Science, Beijing (China); Ferguson, Ian T. [College of Engineering and Computing, Missouri University of Science and Technology, Rolla, MO 65409 (United States)

2016-02-15

The III-Nitrides are promising candidate for high efficiency thermoelectric (TE) materials and devices due to their unique features which includes high thermal stability. A systematic study of the room temperature TE properties of metalorganic chemical vapor deposition grown In{sub x}Ga{sub 1-x}N were investigated for x =  0.07 to 0.24. This paper investigated the role of indium composition on the TE properties of InGaN alloys in particular the structural properties for homogenous material that did not show significant phase separation. The highest Seebeck and power factor values of 507 μV K{sup −1} and 21.84 × 10{sup −4} Wm{sup −1}K{sup −1} were observed, respectively for In{sub 0.07}Ga{sub 0.93}N at room temperature. The highest value of figure-of-merit (ZT) was calculated to be 0.072 for In{sub 0.20}Ga{sub 0.80}N alloy at room temperature.

Plasma immersion ion implantation on 15-5PH stainless steel: influence on fatigue strength and wear resistance

Science.gov (United States)

Bonora, R.; Cioffi, M. O. H.; Voorwald, H. J. C.

2017-05-01

Surface improvement in steels is of great interest for applications in industry. The aim of this investigation is to study the effect of nitrogen ion implantation on the axial fatigue strength and wear resistance of 15-5 PH stainless steel. It is well know that electroplated coatings, which are used to improve abrasive wear and corrosion properties, affects negatively the fatigue strength. It is also important to consider requirements to reduce the use of coated materials with electroplated chromium and cadmium, that produce waste, which is harmful to health and environment. The HVOF (High velocity oxygen fuel) process provides hardness, wear strength and higher fatigue resistance in comparison to electroplated chromium. Plasma immersion ion implantation has been used to enhance the hardness, wear, fatigue and corrosion properties of metals and alloys. In the present research the fatigue life increased twice for 15-5 PH three hours PIII treated in comparison to base material. From the abrasive wear tests a lower pin mass reduction was observed, associated to the superficial treatments. The improvement of fatigue and mechanical performance is attributed to a combination of nitrides phase structure and compressive residual stresses during the PIII treatment.

Plasma immersion ion implantation on 15-5PH stainless steel: influence on fatigue strength and wear resistance

International Nuclear Information System (INIS)

Bonora, R; Cioffi, M O H; Voorwald, H J C

2017-01-01

Surface improvement in steels is of great interest for applications in industry. The aim of this investigation is to study the effect of nitrogen ion implantation on the axial fatigue strength and wear resistance of 15-5 PH stainless steel. It is well know that electroplated coatings, which are used to improve abrasive wear and corrosion properties, affects negatively the fatigue strength. It is also important to consider requirements to reduce the use of coated materials with electroplated chromium and cadmium, that produce waste, which is harmful to health and environment. The HVOF (High velocity oxygen fuel) process provides hardness, wear strength and higher fatigue resistance in comparison to electroplated chromium. Plasma immersion ion implantation has been used to enhance the hardness, wear, fatigue and corrosion properties of metals and alloys. In the present research the fatigue life increased twice for 15-5 PH three hours PIII treated in comparison to base material. From the abrasive wear tests a lower pin mass reduction was observed, associated to the superficial treatments. The improvement of fatigue and mechanical performance is attributed to a combination of nitrides phase structure and compressive residual stresses during the PIII treatment. (paper)

Liquid scintillation spectrometer survey 155Eu liquid activity

International Nuclear Information System (INIS)

Zhang Zuhua

2002-01-01

In the countrywide contrasting survey of 155 Eu activity, 155 Eu liquid activity was determined for the first time through using liquid scintillation spectrometer survey 155 Eu β ray. In survey total uncertainty, determining activity accord with determining activity average value of all a wide variety of survey instrument entering into contrasting survey. But using liquid scintillation spectrometer survey, it is simple and save time, is beyond compare for other survey method. It indicate liquid scintillation spectrometer survey β-γ nuclide activity is effective as well

Microstructure evolution of the Si{sub 3}N{sub 4}/Si{sub 3}N{sub 4} joints brazed using Au-Ni-V filler alloys with different V content

Energy Technology Data Exchange (ETDEWEB)

Sun, Y. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Zhang, J., E-mail: hitzhangjie@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Zhang, H.W.; Fan, G.H.; He, Y.M. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)

2011-08-18

Highlights: > Si{sub 3}N{sub 4} ceramic was brazed using Au-Ni-V filler alloy with different V content. > The microstructure evolution of the joint was study in detail in the paper. > The polygonal Ni{sub 2}SiV{sub 3} and Ni{sub 3}V phase in the joint were investigated by TEM. > The formation of different compounds and alloys in joint was detailed discussed. - Abstract: Au-Ni-V filler alloys with different vanadium contents were designed to braze Si{sub 3}N{sub 4} ceramic at 1373 K for 30 min, and the microstructures of brazing seams were investigated by SEM and TEM. When the Au-Ni-V filler alloy contains 5 at.% V, round-like Ni[Si, V, Au] precipitates form in the Au[Ni] solid solution matrix and a VN reaction layer with 0.5 {mu}m thickness appears on Si{sub 3}N{sub 4} interface. When the V content increases to 10 at.%, a new polygonal Ni{sub 2}SiV{sub 3} phase occurs in the seam, and the Ni[Si, V, Au] precipitate coarsens and VN layer thickens. With increase of V contents to 15 and 20 at.%, laminar Ni[Au] and polygonal Ni{sub 3}V precipitates form. With 25 at.% V content in the filler alloy, the Ni{sub 2}SiV{sub 3} and Ni{sub 3}V precipitates distribute homogenously in the brazing seam. These microstructure evolutions were attributed to the reaction between Si{sub 3}N{sub 4} and vanadium, which forms VN reaction layer and releases Si into the molten alloy.

14 CFR 155.13 - Determinations by FAA.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Determinations by FAA. 155.13 Section 155... FAA. (a) An FAA office that receives a request for a release under this part, and supporting documents... case was referred to it, the FAA advises the airport owner as to whether the release or a modification...

Threshold stress intensity factor for delayed hydride cracking of a recrystallized N18 alloy plate along the rolling direction

International Nuclear Information System (INIS)

Sun Chao; Tan Jun; Ying Shihao; Peng Qian; Li Cong

2010-01-01

The objective of this study is to obtain the threshold stress intensity factor, K IH , for an initiation of delayed hydride cracking in a recrystallized N18 (Zr-Sn-Nb-Fe-Cr) alloy plate which was manufactured in China, gaseously charged with 60 ppm of hydrogen by weight. By using both the load increasing method and load drop method, the K IH 's along the rolling direction were investigated over a temperature range of 150-255 o C. The results showed that K IH along the rolling direction was found to be higher in the load increasing method than that in the load drop method. In the load increasing method, K IH 's of the N18 alloy plate appeared to be in the range of 31-32.5MPa√(m), and K IH in the load drop method appeared to be in the range of 27.5-28.6MPa√(m). This means that the N18 alloy plate has high tolerance for DHC initiation along the rolling direction. The texture of a N18 alloy plate was investigated using an X-ray diffraction and the K IH was discussed based on texture and analytically as a function of the tilting angle of hydride habit planes to the cracking plane.

K2-155

DEFF Research Database (Denmark)

Hirano, Teruyuki; Dai, Fei; Livingston, John H.

2018-01-01

We report on the discovery of three transiting super-Earths around K2-155 (EPIC 210897587), a relatively bright early M dwarf (V = 12.81 mag) observed during Campaign 13 of the NASA K2 mission. To characterize the system and validate the planet candidates, we conducted speckle imaging and high......-dispersion optical spectroscopy, including radial velocity measurements. Based on the K2 light curve and the spectroscopic characterization of the host star, the planet sizes and orbital periods are 1.55(-0.17)(+0.20) R-circle plus and 6.34365 +/- 0.00028 days for the inner planet; 1.95(-0.22)(+0.27) R-circle plus...... and 13.85402 +/- 0.00088 days for the middle planet; and 1.64(-0.17)(+0.18) R-circle plus and 40.6835 +/- 0.0031 days for the outer planet. The outer planet (K2-155d) is near the habitable zone, with an insolation 1.67 +/- 0.38 times that of the Earth. The planet's radius falls within the range between...

Enhancement of TE polarized light extraction efficiency in nanoscale (AlN)m /(GaN)n (m>n) superlattice substitution for Al-rich AlGaN disorder alloy: ultra-thin GaN layer modulation

International Nuclear Information System (INIS)

Jiang, Xin-he; Shi, Jun-jie; Zhong, Hong-xia; Huang, Pu; Ding, Yi-min; Yu, Tong-jun; Shen, Bo; Lu, Jing; Zhang, Min; Wang, Xihua

2014-01-01

The problem of achieving high light extraction efficiency in Al-rich Al x Ga 1−x N is of paramount importance for the realization of AlGaN-based deep ultraviolet (DUV) optoelectronic devices. To solve this problem, we investigate the microscopic mechanism of valence band inversion and light polarization, a crucial factor for enhancing light extraction efficiency, in Al-rich Al x Ga 1−x N alloy using the Heyd–Scuseria–Ernzerhof hybrid functional, local-density approximation with 1/2 occupation, and the Perdew–Burke–Ernzerhof functional, in which the spin–orbit coupling effect is included. We find that the microscopic Ga-atom distribution can effectively modulate the valence band structure of Al-rich Al x Ga 1−x N. Moreover, we prove that the valence band arrangement in the decreasing order of heavy hole, light hole, and crystal-field split-off hole can be realized by using nanoscale (AlN) m /(GaN) n (m>n) superlattice (SL) substituting for Al-rich Al x Ga 1−x N disorder alloy as the active layer of optoelectronic devices due to the ultra-thin GaN layer modulation. The valence band maximum, i.e., the heavy hole band, has p x - and p y -like characteristics and is highly localized in the SL structure, which leads to the desired transverse electric (TE) polarized (E⊥c) light emission with improved light extraction efficiency in the DUV spectral region. Some important band-structure parameters and electron/hole effective masses are also given. The physical origin for the valence band inversion and TE polarization in (AlN) m /(GaN) n SL is analyzed in depth. (paper)

17 CFR 155.3 - Trading standards for futures commission merchants.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Trading standards for futures commission merchants. 155.3 Section 155.3 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION TRADING STANDARDS § 155.3 Trading standards for futures commission merchants. (a) Each futures...

33 CFR 157.155 - COW operations: General.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false COW operations: General. 157.155... Crude Oil Washing (COW) System on Tank Vessels Cow Operations § 157.155 COW operations: General. (a) The master of a tank vessel having a COW system under § 157.10(e), § 157.10a(a)(2), or 157.10c(b)(2) shall...

Soil CO2, CH4 and N2O effluxes and concentrations in soil profiles down to 15.5m depth in eucalypt plantations under contrasted rainfall regimes

Science.gov (United States)

Germon, A.; Nouvellon, Y.; Christophe, J.; Chapuis-Lardy, L.; Robin, A.; Rosolem, C. A.; Gonçalves, J. L. D. M.; Guerrini, I. A.; Laclau, J. P.

2017-12-01

Silvicultural practices in planted forests affect the fluxes of greenhouse gases at the soil surface and the major factors driving greenhouse gas production in forest soils (substrate supply, temperature, water content,…) vary with soil depth. Our study aimed to assess the consequences of drought on the temporal variability of CO2, CH4 and N2O fluxes throughout very deep soil profiles in Eucalyptus grandis plantations 3 months before the harvest then in coppice, the first 18 months after clear-cutting. Two treatments were compared: one with 37% of throughfall excluded by plastic sheets (TE), and one without rainfall exclusion (WE). Measurements of soil CO2 efflux were made every two weeks for 30 months using a closed-path Li8100 system in both treatment. Every two weeks for 21 months, CO2, CH4 and N2O surface effluxes were measured using the closed-chamber method and concentrations in the soil were measured at 7 depths down to 15.5 m in both TE and WE. At most measurement dates, soil CO2 efflux were significantly higher in TE than in WE. Across the two treatments and the measurement dates, CO2 concentrations increased from 4446 ± 2188 ppm at 10 cm deep to 15622 ± 3523 ppm at 15.5 m, CH4 concentrations increased from 0.41 ± 0.17 ppm at 10 cm deep to 0.77 ± 0.24 ppm at 15.5 m and N2O concentrations remained roughly constant and were on average 478 ± 55 ppb between soil surface and 15.5 m deep. CO2 and N2O concentrations were on average 20.7 and 7.6% lower in TE than in WE, respectively, across the sampling depths. However, CH4 concentrations in TE were on average 44.4% higher than in WE, throughout the soil profile. Those results suggest that extended drought periods might reduce the production of CO2 and N2O but increase the accumulation of CH4 in eucalypt plantations established in deep tropical soils. Very deep tropical soils cover huge areas worldwide and improving our understanding of the spatiotemporal dynamics of gas concentrations in deep soil layers

Tribological Behavior of Babbitt Alloy Rubbing Against Si3N4 and Steel Under Dry Friction Condition

Science.gov (United States)

Ji, Xianbing; Chen, Yinxia

2016-03-01

The tribological behavior of Babbitt alloy rubbing with Si3N4 ball and steel ball with various sliding speeds at dry friction condition was investigated. It was found that B88 alloy rubbing with Si3N4 ball and steel ball possesses a low sliding wear resistance at dry friction. The wear rate is above 10-4 mm3/Nm, and the friction coefficient is from 0.2 to 0.4. At low sliding speed of 0.05-0.1 m/s, the mainly wear mechanisms are microgroove and fatigue wear, while at high sliding speed of 0.5 m/s, the wear mechanisms depend on plastic deformation and delamination. The high wear rate indicates that it is needed to prevent Babbitt alloy from working at dry friction conditions, while the low friction coefficient suggests that it is not easy to the occurrence of cold weld.

17 CFR 201.155 - Default; motion to set aside default.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Default; motion to set aside default. 201.155 Section 201.155 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION RULES OF PRACTICE Rules of Practice General Rules § 201.155 Default; motion to set aside default. (a) A...

Study of the nuclear structure of {sup 155}Eu; Estudo da estrutura nuclear do {sup 155}Eu

Energy Technology Data Exchange (ETDEWEB)

Genezini, Frederico Antonio

2004-07-01

The {sup 155}Eu nuclide was investigated by the directional angular correlation technique following the {beta} decay of {sup 155}Sm. The angular correlation measurements were carried out using a setup with 4 Ge detectors and a multi parametric data acquisition system. To perform the data analysis a new methodology was developed . The multipole mixing ratios of twenty sixty {gamma}- transitions were determined. Seven of them agreed with the results of earlier angular correlation studies and nineteen obtained for the first time confirmed the multipolarity suggested in earlier electron capture studies. Besides, the spin of the level at 1106.83 keV as well as the parity of the level at 1301.41 keV have also been suggested. The nuclear structure of {sup 155}Eu was discussed successfully in terms of the single particle model using a deformed Woods-Saxon potential plus residual pairing interaction permitting the description of the rotational quasi-proton band heads. (author)

miR-155 as a Biomarker in B-Cell Malignancies

Directory of Open Access Journals (Sweden)

Hanne Due

2016-01-01

Full Text Available MicroRNAs have the potential to be useful biomarkers in the development of individualized treatment since they are easy to detect, are relatively stable during sample handling, and are important determinants of cellular processes controlling pathogenesis, progression, and response to treatment of several types of cancers including B-cell malignancies. miR-155 is an oncomiR with a crucial role in tumor initiation and development of several B-cell malignancies. The present review elucidates the potential of miR-155 as a diagnostic, prognostic, or predictive biomarker in B-cell malignancies using a systematic search strategy to identify relevant literature. miR-155 was upregulated in several malignancies compared to nonmalignant controls and overexpression of miR-155 was further associated with poor prognosis. Elevated expression of miR-155 shows potential as a diagnostic and prognostic biomarker in diffuse large B-cell lymphoma and chronic lymphocytic leukemia. Additionally, in vitro and in vivo studies suggest miR-155 as an efficient therapeutic target, supporting its oncogenic function. The use of inhibiting anti-miR structures indicates promising potential as novel anticancer therapeutics. Reports from 53 studies prove that miR-155 has the potential to be a molecular tool in personalized medicine.

21 CFR 155.200 - Certain other canned vegetables.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Certain other canned vegetables. 155.200 Section 155.200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED VEGETABLES Requirements for Specific Standardized Canned...

Threshold stress intensity factor for delayed hydride cracking of a recrystallized N18 alloy plate along the rolling direction

Energy Technology Data Exchange (ETDEWEB)

Sun Chao, E-mail: sunchaonpic@yahoo.com.c [National Key Laboratory for Nuclear Fuel and Materials, Nuclear Power Institute of China, P.O. Box 436, Chengdu 610041 (China); Tan Jun; Ying Shihao; Peng Qian [National Key Laboratory for Nuclear Fuel and Materials, Nuclear Power Institute of China, P.O. Box 436, Chengdu 610041 (China); Li Cong [Department of R and D, State Nuclear Power Technology Corporation Limited, Beijing (China)

2010-11-15

The objective of this study is to obtain the threshold stress intensity factor, K{sub IH}, for an initiation of delayed hydride cracking in a recrystallized N18 (Zr-Sn-Nb-Fe-Cr) alloy plate which was manufactured in China, gaseously charged with 60 ppm of hydrogen by weight. By using both the load increasing method and load drop method, the K{sub IH}'s along the rolling direction were investigated over a temperature range of 150-255 {sup o}C. The results showed that K{sub IH} along the rolling direction was found to be higher in the load increasing method than that in the load drop method. In the load increasing method, K{sub IH}'s of the N18 alloy plate appeared to be in the range of 31-32.5MPa{radical}(m), and K{sub IH} in the load drop method appeared to be in the range of 27.5-28.6MPa{radical}(m). This means that the N18 alloy plate has high tolerance for DHC initiation along the rolling direction. The texture of a N18 alloy plate was investigated using an X-ray diffraction and the K{sub IH} was discussed based on texture and analytically as a function of the tilting angle of hydride habit planes to the cracking plane.

Microstructure and properties of nitrogen ion implantation/AlN/CrAlN/MoS{sub 2}-phenolic resin duplex coatings on magnesium alloys

Energy Technology Data Exchange (ETDEWEB)

Xie, Zhiwen [University of Science and Technology Liaoning, Anshan 114051 (China); Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714 (China); Chen, Qiang, E-mail: 2009chenqiang@163.com [Southwest Technique and Engineering Research Institute, Chongqing 400039 (China); Chen, Tian [Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714 (China); Gao, Xu; Yu, Xiaoguang; Song, Hua; Feng, Yongjun [University of Science and Technology Liaoning, Anshan 114051 (China)

2015-06-15

The novel nitrogen ion implantation/AlN/CrAlN/MoS{sub 2}-phenolic resin duplex coatings are fabricated on the AM60 magnesium alloys. The microstructure, tribological and electrochemical properties of the duplex coatings are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, nano-indenter, electrochemical corrosion and wear tester. These studies reveal that the MoS{sub 2}-phenolic resin coating has a two-phase microstructure crystalline MoS{sub 2} particles embedded in the amorphous phenolic resin matrix. The single-layer MoS{sub 2}-phenolic resin enhances the corrosion resistance of magnesium alloys, but shows poor wear resistance due to the low substrate's load bearing capacity. The addition of nitrogen ion implantation/AlN/CrAlN interlayer in the MoS{sub 2}-phenolic resin/substrate system greatly enhances the substrate's load bearing capacity. The AlN/CrAlN/MoS{sub 2}-phenolic resin duplex coating with a high load bearing capacity demonstrates super wear resistance (i.e., long wear life and low friction coefficient). In addition, the nitrogen ion implantation/AlN interlayer greatly depresses the effect of galvanic corrosion because its potential is close to that of the magnesium alloys, but the nitrogen ion implantation/AlN/CrAlN interlayer is inefficient in reducing the galvanic corrosion due to the large potential difference between the CrN phase and the substrate. As a result, the nitrogen ion implantation/AlN/MoS{sub 2}-phenolic resin duplex coating shows a better corrosion resistance compared to the nitrogen ion implantation/AlN/CrAlN/MoS{sub 2}-phenolic resin. - Highlights: • Ion implantation/AlN/CrAlN/MoS{sub 2}-phenolic resin duplex coatings were presented. • Ion implantation/AlN/CrAlN interlayer greatly enhanced the load bearing capacity. • Ion implantation/AlN interlayer greatly depressed the effect of galvanic corrosion. • The

The Emerging Role of MicroRNA-155 in Cardiovascular Diseases

Directory of Open Access Journals (Sweden)

Richard Y. Cao

2016-01-01

Full Text Available MicroRNAs have been demonstrated to be involved in human diseases, including cardiovascular diseases. Growing evidences suggest that microRNA-155, a typical multifunctional microRNA, plays a crucial role in hematopoietic lineage differentiation, immunity, inflammation, viral infections, and vascular remodeling, which is linked to cardiovascular diseases such as coronary artery disease, abdominal aortic aneurysm, heart failure, and diabetic heart disease. The effects of microRNA-155 in different cell types through different target genes result in different mechanisms in diseases. MicroRNA-155 has been intensively studied in atherosclerosis and coronary artery disease. Contradictory results of microRNA-155 either promoting or preventing the pathophysiological process of atherosclerosis illustrate the complexity of this pleiotropic molecule. Therefore, more comprehensive studies of the underlying mechanisms of microRNA-155 involvement in cardiovascular diseases are required. Furthermore, a recent clinical trial of Miravirsen targeting microRNA-122 sheds light on exploiting microRNA-155 as a novel target to develop effective therapeutic strategies for cardiovascular diseases in the near future.

Microstructure influence on corrosion behavior of a Fe–Cr–V–N tool alloy studied by SEM/EDS, scanning Kelvin force microscopy and electrochemical measurement

International Nuclear Information System (INIS)

Sababi, Majid; Ejnermark, Sebastian; Andersson, Jörgen; Claesson, Per M.; Pan, Jinshan

2013-01-01

Highlights: ► Localized corrosion of a new N-based tool alloy (Fe–Cr–V–N) has been studied. ► One-pass mode of scanning Kelvin force microscopy (KFM) was used in the study. ► The focus was on correlation between microstructure and localized corrosion. - Abstract: Microstructure influence on corrosion behavior of an N-based tool alloy (Fe–Cr–V–N) has been studied. Electron microscopy analysis showed two types of hard phases in the alloy. One-pass mode scanning Kelvin force microscopy (KFM) was used to investigate relative nobility of the hard phases. Volta potential mapping indicates higher nobility for the hard phases than the alloy matrix, and, the V- and N-rich particles exhibit the highest Volta potential. Post-polarization analysis by SEM revealed localized dissolution initiated in matrix regions adjacent to hard phase particles, and the boundary region surrounding the Cr- and Mo-rich particles is more prone to localized corrosion.

First principles examination of electronic structure and optical features of 4H-GaN1-xPx polytype alloys

Science.gov (United States)

Laref, A.; Hussain, Z.; Laref, S.; Yang, J. T.; Xiong, Y. C.; Luo, S. J.

2018-04-01

By using first-principles calculations, we compute the electronic band structures and typical aspects of the optical spectra of hexagonally structured GaN1-xPx alloys. Although a type III-V semiconductor, GaP commonly possesses a zinc-blende structure with an indirect band gap; as such, it may additionally form hexagonal polytypes under specific growth conditions. The electronic structures and optical properties are calculated by combining a non-nitride III-V semiconductor and a nitride III-V semiconductor, as GaP and GaN crystallizing in a 4H polytype, with the N composition ranging between x = 0-1. For all studied materials, the energy gap is found to be direct. The optical properties of the hexagonal materials may illustrate the strong polarization dependence owing to the crystalline anisotropy. This investigation for GaN1-xPx alloys is anticipated to supply paramount information for applications in the visible/ultraviolet spectral regions. At a specific concentration, x, these alloys would be exclusively appealing candidates for solar-cell applications.

27 CFR 28.155 - Consignment, shipment, and delivery.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Consignment, shipment, and delivery. 28.155 Section 28.155 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE..., and delivery. The consignment, shipment, and delivery of specially denatured spirits withdrawn free of...

Critical role of microRNA-155 in herpes simplex encephalitis.

Science.gov (United States)

Bhela, Siddheshvar; Mulik, Sachin; Reddy, Pradeep B J; Richardson, Raphael L; Gimenez, Fernanda; Rajasagi, Naveen K; Veiga-Parga, Tamara; Osmand, Alexander P; Rouse, Barry T

2014-03-15

HSV infection of adult humans occasionally results in life-threatening herpes simplex encephalitis (HSE) for reasons that remain to be defined. An animal system that could prove useful to model HSE could be microRNA-155 knockout (miR-155KO) mice. Thus, we observe that mice with a deficiency of miR-155 are highly susceptible to HSE with a majority of animals (75-80%) experiencing development of HSE after ocular infection with HSV-1. The lesions appeared to primarily represent the destructive consequences of viral replication, and animals could be protected from HSE by acyclovir treatment provided 4 d after ocular infection. The miR-155KO animals were also more susceptible to development of zosteriform lesions, a reflection of viral replication and dissemination within the nervous system. One explanation for the heightened susceptibility to HSE and zosteriform lesions could be because miR-155KO animals develop diminished CD8 T cell responses when the numbers, functionality, and homing capacity of effector CD8 T cell responses were compared. Indeed, adoptive transfer of HSV-immune CD8 T cells to infected miR-155KO mice at 24 h postinfection provided protection from HSE. Deficiencies in CD8 T cell numbers and function also explained the observation that miR-155KO animals were less able than control animals to maintain HSV latency. To our knowledge, our observations may be the first to link miR-155 expression with increased susceptibility of the nervous system to virus infection.

Undoped p-type GaN1-xSbx alloys: Effects of annealing

Science.gov (United States)

Segercrantz, N.; Baumgartner, Y.; Ting, M.; Yu, K. M.; Mao, S. S.; Sarney, W. L.; Svensson, S. P.; Walukiewicz, W.

2016-12-01

We report p-type behavior for undoped GaN1-xSbx alloys with x ≥ 0.06 grown by molecular beam epitaxy at low temperatures (≤400 °C). Rapid thermal annealing of the GaN1-xSbx films at temperatures >400 °C is shown to generate hole concentrations greater than 1019 cm-3, an order of magnitude higher than typical p-type GaN achieved by Mg doping. The p-type conductivity is attributed to a large upward shift of the valence band edge resulting from the band anticrossing interaction between localized Sb levels and extended states of the host matrix.

High thermally stable Ni /Ag(Al) alloy contacts on p-GaN

Science.gov (United States)

Chou, C. H.; Lin, C. L.; Chuang, Y. C.; Bor, H. Y.; Liu, C. Y.

2007-01-01

Ag agglomeration was found to occur at Ni /Ag to p-GaN contacts after annealing at 500°C. This Ag agglomeration led to the poor thermal stability showed by the Ni /Ag contacts in relation to the reflectivity and electrical properties. However, after alloying with 10at.% Al by e-gun deposition, the Ni /Ag(Al) p-GaN contacts were found to effectively retard Ag agglomeration thereby greatly enhancing the thermal stability. Based on the x-ray photoelectron spectroscopy analysis, the authors believe that the key for the retardation of Ag agglomeration was the formation of ternary Al-Ni-O layer at p-GaN interface.

Joining of Si3N4 ceramic using PdCo(NiSiB–V system brazing filler alloy and interfacial reactions

Directory of Open Access Journals (Sweden)

Huaping Xiong

2014-02-01

Full Text Available The wettability of V-active PdCo-based alloys on Si3N4 ceramic was studied with the sessile drop method. And the alloy of Pd50.0–Co33.7–Ni4.0–Si2.0–B0.7–V9.6 (wt%, was developed for Si3N4 ceramic joining in the present investigation. The rapidly-solidified brazing foils were fabricated by the alloy Pd50.0–Co33.7–Ni4.0–Si2.0–B0.7–V9.6. The average room-temperature three-point bend strength of the Si3N4/Si3N4 joints brazed at 1453 K for 10 min was 205.6 MPa, and the newly developed braze gives joint strengths of 210.9 MPa, 206.6 MPa and 80.2 MPa at high temperatures of 973 K, 1073 K and 1173 K respectively. The interfacial reaction products in the Si3N4/Si3N4 joint brazed at 1453 K for 10 min were identified to be VN and Pd2Si by XRD analysis. Based on the XEDS analysis result, the residual brazing alloy existing at the central part of the joint was verified as Co-rich phases, in which the concentration of element Pd was high up to 18.0–19.1 at%. The mechanism of the interfacial reactions was discussed. Pd should be a good choice as useful alloying element in newer high-temperature braze candidates for the joining of Si-based ceramics.

MicroRNA-155 knockout mice are susceptible to Mycobacterium tuberculosis infection.

Science.gov (United States)

Iwai, Hiroki; Funatogawa, Keiji; Matsumura, Kazunori; Kato-Miyazawa, Masako; Kirikae, Fumiko; Kiga, Kotaro; Sasakawa, Chihiro; Miyoshi-Akiyama, Tohru; Kirikae, Teruo

2015-05-01

MicroRNAs (miRNAs) are short, conserved, non-coding RNA molecules that repress translation, followed by the decay of miRNA-targeted mRNAs that encode molecules involved in cell differentiation, development, immunity and apoptosis. At least six miRNAs, including microRNA-155 (miR-155), were up-regulated when born marrow-derived macrophages from C57BL/6 mice were infected with Mycobacterium tuberculosis Erdman. C57BL/6 mice intravenously infected with Erdman showed up-regulation of miR-155 in livers and lungs. Following infection, miR-155-deficient C57BL/6 mice died significantly earlier and had significantly higher numbers of CFU in lungs than wild-type mice. Moreover, fewer CD4(+) T cells, but higher numbers of monocytes and neutrophils, were present in the lungs of Erdman-infected miR-155 knockout (miR-155(-/-)) than of wild-type mice. These findings indicated that miR-155 plays a critical role in immune responses to M. tuberculosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ab Initio Molecular Dynamics Studies of Pb m Sb n ( m + n ≤ 9) Alloy Clusters

Science.gov (United States)

Song, Bingyi; Xu, Baoqiang; Yang, Bin; Jiang, Wenlong; Chen, Xiumin; Xu, Na; Liu, Dachun; Dai, Yongnian

2017-10-01

Structure, stability, and dynamics of Pb m Sb n ( m + n ≤ 9) clusters were investigated using ab initio molecular dynamics. Size dependence of binding energies, the second-order energy difference of clusters, dissociation energy, HOMO-LUMO gaps, Mayer bond order, and the diffusion coefficient of Pb m Sb n clusters were discussed. Results suggest that Pb3Sb2, Pb4Sb2, and Pb5Sb4 ( n = 2 or 4) clusters have higher stability than other clusters, which is consistent with previous findings. In case of Pb-Sb alloy, the dynamics results show that Pb4Sb2 (Pb-22.71 wt pct Sb) can exist in gas phase at 1073 K (800 °C), which reasonably explains the azeotropic phenomenon, and the calculated values are in agreement with the experimental results (Pb-22 wt pct Sb).

Master curve characterization of the fracture toughness behavior in SA508 Gr.4N low alloy steels

Energy Technology Data Exchange (ETDEWEB)

Lee, Ki-Hyoung, E-mail: shirimp@kaist.ac.k [Department of Materials Science and Engineering, KAIST, Daejeon 305-701 (Korea, Republic of); Kim, Min-Chul; Lee, Bong-Sang [Nuclear Materials Research Division, KAERI, Daejeon 305-353 (Korea, Republic of); Wee, Dang-Moon [Department of Materials Science and Engineering, KAIST, Daejeon 305-701 (Korea, Republic of)

2010-08-15

The fracture toughness properties of the tempered martensitic SA508 Gr.4N Ni-Mo-Cr low alloy steel for reactor pressure vessels were investigated by using the master curve concept. These results were compared to those of the bainitic SA508 Gr.3 Mn-Mo-Ni low alloy steel, which is a commercial RPV material. The fracture toughness tests were conducted by 3-point bending with pre-cracked charpy (PCVN) specimens according to the ASTM E1921-09c standard method. The temperature dependency of the fracture toughness was steeper than those predicted by the standard master curve, while the bainitic SA508 Gr.3 steel fitted well with the standard prediction. In order to properly evaluate the fracture toughness of the Gr.4N steels, the exponential coefficient of the master curve equation was changed and the modified curve was applied to the fracture toughness test results of model alloys that have various chemical compositions. It was found that the modified curve provided a better description for the overall fracture toughness behavior and adequate T{sub 0} determination for the tempered martensitic SA508 Gr.4N steels.

14 CFR 91.155 - Basic VFR weather minimums.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Basic VFR weather minimums. 91.155 Section...) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Flight Rules Visual Flight Rules § 91.155 Basic VFR weather minimums. (a) Except as provided in paragraph (b) of this section and...

21 CFR 516.155 - Labeling of indexed drugs.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Labeling of indexed drugs. 516.155 Section 516.155 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS NEW ANIMAL DRUGS FOR MINOR USE AND MINOR SPECIES Index of Legally...

Stress corrosion crack tip microstructure in nickel-based alloys

International Nuclear Information System (INIS)

Shei, S.A.; Yang, W.J.

1994-04-01

Stress corrosion cracking behavior of several nickel-base alloys in high temperature caustic environments has been evaluated. The crack tip and fracture surfaces were examined using Auger/ESCA and Analytical Electron Microscopy (AEM) to determine the near crack tip microstructure and microchemistry. Results showed formation of chromium-rich oxides at or near the crack tip and nickel-rich de-alloying layers away from the crack tip. The stress corrosion resistance of different nickel-base alloys in caustic may be explained by the preferential oxidation and dissolution of different alloying elements at the crack tip. Alloy 600 (UNS N06600) shows good general corrosion and intergranular attack resistance in caustic because of its high nickel content. Thermally treated Alloy 690 (UNS N06690) and Alloy 600 provide good stress corrosion cracking resistance because of high chromium contents along grain boundaries. Alloy 625 (UNS N06625) does not show as good stress corrosion cracking resistance as Alloy 690 or Alloy 600 because of its high molybdenum content

MiR-155 modulates the progression of neuropathic pain through targeting SGK3.

Science.gov (United States)

Liu, Shaoxing; Zhu, Bo; Sun, Yan; Xie, Xianfeng

2015-01-01

This study aimed to illustrate the potential effects of miR-155 in neuropathic pain and its potential mechanism. Spragure-Dawley (SD) rats were used for neuropathic pain model of bilateral chronic constriction injury (bCCI) construction. Effects of miR-155 expression on pain threshold of mechanical stimuli (MWT), paw withdrawal threshold latency (PMTL) and cold threshold were analyzed. Target for miR-155 was analyzed using bioinformatics methods. Moreover, effects of miR-155 target gene expression on pain thresholds were also assessed. Compared with the controls and sham group, miR-155 was overexpressed in neuropathic pain rats (P<0.05), but miR-155 slicing could significantly decreased the pain thresholds (P<0.05). Serum and glucocorticoid regulated protein kinase 3 (SGK3) was predicted as the target gene for miR-155, and miR-155 expression was negatively correlated to SGK3 expression. Furthermore, SGK3 overexpression could significantly decreased the pain thresholds which was the same as miR-155 (P<0.05). Moreover, miR-155 slicing and SGK3 overexpression could significantly decrease the painthreshold. The data presented in this study suggested that miR-155 slicing could excellently alleviate neuropathic pain in rats through targeting SGK3 expression. miR-155 may be a potential therapeutic target for neuropathic pain treatment.

Microstructure and mechanical behavior of superelastic Ti-24Nb-0.5O and Ti-24Nb-0.5N biomedical alloys.

Science.gov (United States)

Ramarolahy, A; Castany, P; Prima, F; Laheurte, P; Péron, I; Gloriant, T

2012-05-01

In this study, the microstructure and the mechanical properties of two new biocompatible superelastic alloys, Ti-24Nb-0.5O and Ti-24Nb-0.5N (at.%), were investigated. Special attention was focused on the role of O and N addition on α(″) formation, supereleastic recovery and mechanical strength by comparison with the Ti-24Nb and Ti-26Nb (at.%) alloy compositions taken as references. Microstructures were characterized by optical microscopy, X-ray diffraction and transmission electron microscopy before and after deformation. The mechanical properties and the superelastic behavior were evaluated by conventional and cyclic tensile tests. High tensile strength, low Young's modulus, rather high superelastic recovery and excellent ductility were observed for both superelastic Ti-24Nb-0.5O and Ti-24Nb-0.5N alloys. Deformation twinning was shown to accommodate the plastic deformation in these alloys and only the {332} twinning system was observed to be activated by electron backscattered diffraction analyses. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evaluation of the Precipitation Behavior in SA508 Gr. 4N Low Alloy Steel Using a Thermodynamic Calculation

International Nuclear Information System (INIS)

Park, Sang Gyu; Wee, Dang Moon; Kim, Min Chul; Lee, Bong Sang

2007-01-01

Low carbon low alloy steels, used as nuclear pressure vessels, steam generators and so on, hold a large portion of materials for nuclear power plants, and they are very important materials since they determine the safety and the life span of nuclear power plants. In addition, they are utilized for a long period under very severe conditions such as a high pressure, high temperature, neutron irradiation and corrosion, so they need a good combination of strength and toughness, a good weldability and an excellent neutron irradiation resistance and so on. SA508 Gr.3 steel shows the upper bainite microstructure, which is a less tough, so the steel is more difficult to obtain good toughness than to have good strength. And then, if a loss of toughness due to a neutron irradiation during service is considered, above all improving the toughness is important when a pressure vessel is fabricated It is known that a higher strength and fracture toughness of low alloy steels could be achieved by increasing the Ni and Cr contents. In this study, we have performed a thermodynamic calculation based on the microstructure of SA508 Gr.4N low alloy steel which has higher Ni and Cr contents than SA508 Gr.3 low alloy steel. Based on the microstructure/property relations obtained from literature research experimental works on SA508 Gr.4N steels, and by predicting the constitutional changes with alloying elements (such as Mn, Cr) during individual steps of a steel making process a using thermodynamic calculation, fundamental information for an alloy design have been discussed

The electronic and optical properties of quaternary GaAs1-x-y N x Bi y alloy lattice-matched to GaAs: a first-principles study.

Science.gov (United States)

Ma, Xiaoyang; Li, Dechun; Zhao, Shengzhi; Li, Guiqiu; Yang, Kejian

2014-01-01

First-principles calculations based on density functional theory have been performed for the quaternary GaAs1-x-y N x Bi y alloy lattice-matched to GaAs. Using the state-of-the-art computational method with the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional, electronic, and optical properties were obtained, including band structures, density of states (DOSs), dielectric function, absorption coefficient, refractive index, energy loss function, and reflectivity. It is found that the lattice constant of GaAs1-x-y N x Bi y alloy with y/x =1.718 can match to GaAs. With the incorporation of N and Bi into GaAs, the band gap of GaAs1-x-y N x Bi y becomes small and remains direct. The calculated optical properties indicate that GaAs1-x-y N x Bi y has higher optical efficiency as it has less energy loss than GaAs. In addition, it is also found that the electronic and optical properties of GaAs1-x-y N x Bi y alloy can be further controlled by tuning the N and Bi compositions in this alloy. These results suggest promising applications of GaAs1-x-y N x Bi y quaternary alloys in optoelectronic devices.

33 CFR 110.155 - Port of New York.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Port of New York. 110.155 Section... ANCHORAGE REGULATIONS Anchorage Grounds § 110.155 Port of New York. (a) Long Island Sound—(1) Anchorage No... northwest corner of the crib icebreaker north of the New York Central Railroad Company drawbridge across...

Coercivity and induced magnetic anisotropy by stress and/or field annealing in Fe- and Co- based (Finemet-type) amorphous alloys

International Nuclear Information System (INIS)

Miguel, C.; Zhukov, A.; Val, J.J. del; Gonzalez, J.

2005-01-01

Uniaxial magnetic anisotropy has been induced in amorphous Fe 73.5 Cu 1 Nb 3 Si 15.5 B 7 (Fe-rich) and (Co 77 Si 13.5 B 9.5 ) 90 Fe 7 Nb 3 (Co-rich) ferromagnetic alloys by annealing under stress and/or magnetic field. Such anisotropy plays a crucial role on the magnetization process and, consequently, determine the future applications of these materials. The mechanisms involved on the origin of such induced magnetic anisotropy showed significant differences between Fe-rich and Co-rich amorphous alloys. This work provides a comparative study of the coercive field and induced magnetic anisotropy in Fe-rich and Co-rich (Finemet) amorphous alloys treated by stress and/or field

Degradation behavior of n-MAO/EPD bio-ceramic composite coatings on magnesium alloy in simulated body fluid

Energy Technology Data Exchange (ETDEWEB)

Xiong, Ying, E-mail: yxiong@zjut.edu.cn [College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Lu, Chao [College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Wang, Chao; Song, Renguo [School of Materials Science and Engineering, Changzhou University, Changzhou 213164 (China); Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Changzhou 213164 (China)

2015-03-15

Highlights: • A bio-ceramic n-MAO/EPD coating was prepared by combined MAO and EPD technique. • The precipitates of Ca/P compound are formed on the surface samples during immersion. • The n-MAO/EPD coating with HA dense structure has a favorable anti-corrosion effect. • Two degradation mechanism models for the n-MAO and n-MAO/EPD coating were proposed. - Abstract: The bio-ceramic composite coatings have been fabricated on ZK60 magnesium (Mg) alloy to improve its bio-corrosion resistance in a simulated body fluid (SBF). Firstly, micro-arc oxidation coatings (n-MAO coating) with the addition of zirconium oxide (ZrO{sub 2}) and cerium oxide (CeO{sub 2}) nano-particles were prepared by MAO technique on ZK60Mg alloy in alkaline electrolyte. Secondly, nano-hydroxyapatite (HA) was deposited on the surface of n-MAO coatings by using electrophoretic deposition (EPD) technique. The degradation behavior of the coated samples was investigated by means of immersion tests and electrochemical impedance spectroscopy (EIS) in the SBF at 36.5 ± 0.5 °C. The variation of phase composition, surface and cross-section morphology of coatings at different immersion stages were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results showed that the precipitation layer with biological activity formed on the surface of coated samples during the SBF immersion, which can inhibit Mg alloys from degrading effectively. The n-MAO/EPD composite coating with HA dense structure has a favorable anti-corrosion effect compared to the n-MAO coating. Degradation mechanism model of the corrosion process at different corrosion stages for two kinds of coatings were proposed. The long-term corrosion protection of the n-MAO/EPD composite coating was governed significantly by the synergistic effect of phase composition stability and micro structural integrity.

A graded nano-TiN coating on biomedical Ti alloy: Low friction coefficient, good bonding and biocompatibility

Energy Technology Data Exchange (ETDEWEB)

Cui, Wenfang [Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), School of Material Science and Engineering, Northeastern University, Shenyang 110819 (China); Qin, Gaowu, E-mail: qingw@smm.neu.edu.cn [Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), School of Material Science and Engineering, Northeastern University, Shenyang 110819 (China); Duan, Jingzhu; Wang, Huan [Spinal surgery, Shengjing Hospital, China Medical University, Shenyang 110004 (China)

2017-02-01

In order to solve wear resistance of Ti alloy biomaterials, the concept of a graded nano-TiN coating has been proposed. The coating was prepared on Ti-6Al-4V bio-alloy by DC reactive magnetron sputtering. The wear performance of the coated specimens was measured in Hank's solution under the load of 10 N, and the biocompatibility was evaluated according to ISO-10993-4 standard. The results show that the gradient coating exhibits a gradual change in compositions and microstructures along the direction of film growth. Nano-TiN with the size of several to dozens nanometers and Ti{sub 4}N{sub 3−x} transitional phase with variable composition form a graded composite structure, which significantly improves adhesion strength (L{sub c1} = 80 N, L{sub c2} = 120 N), hardness (21 GPa) and anti-wear performance (6.2 × 10{sup −7} mm{sup 3}/Nm). The excellent bonding and wear resistance result from a good match of mechanical properties at substrate/coating interface and the strengthening and toughening effects of the nanocrystalline composite. The nano-TiN coating has also been proved to have good biocompatibility through in-vitro cytotoxicity, hemocompatibility and general toxicity tests. And thus, the proposed graded nano-TiN coating is a good candidate improving wear resistance of many implant medical devices. - Highlights: • A graded nano-TiN coating was prepared on biomedical Ti alloy by PVD. • The combination of hard and soft phase increases hardness and toughness. • The coating exhibits high bonding, low coefficient of friction and wear rate. • The new coating has good bio-safety and great clinical application prospect.

Degradation behavior of n-MAO/EPD bio-ceramic composite coatings on magnesium alloy in simulated body fluid

International Nuclear Information System (INIS)

Xiong, Ying; Lu, Chao; Wang, Chao; Song, Renguo

2015-01-01

Highlights: • A bio-ceramic n-MAO/EPD coating was prepared by combined MAO and EPD technique. • The precipitates of Ca/P compound are formed on the surface samples during immersion. • The n-MAO/EPD coating with HA dense structure has a favorable anti-corrosion effect. • Two degradation mechanism models for the n-MAO and n-MAO/EPD coating were proposed. - Abstract: The bio-ceramic composite coatings have been fabricated on ZK60 magnesium (Mg) alloy to improve its bio-corrosion resistance in a simulated body fluid (SBF). Firstly, micro-arc oxidation coatings (n-MAO coating) with the addition of zirconium oxide (ZrO 2 ) and cerium oxide (CeO 2 ) nano-particles were prepared by MAO technique on ZK60Mg alloy in alkaline electrolyte. Secondly, nano-hydroxyapatite (HA) was deposited on the surface of n-MAO coatings by using electrophoretic deposition (EPD) technique. The degradation behavior of the coated samples was investigated by means of immersion tests and electrochemical impedance spectroscopy (EIS) in the SBF at 36.5 ± 0.5 °C. The variation of phase composition, surface and cross-section morphology of coatings at different immersion stages were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results showed that the precipitation layer with biological activity formed on the surface of coated samples during the SBF immersion, which can inhibit Mg alloys from degrading effectively. The n-MAO/EPD composite coating with HA dense structure has a favorable anti-corrosion effect compared to the n-MAO coating. Degradation mechanism model of the corrosion process at different corrosion stages for two kinds of coatings were proposed. The long-term corrosion protection of the n-MAO/EPD composite coating was governed significantly by the synergistic effect of phase composition stability and micro structural integrity

Comparison on Mechanical Properties of SA508 Gr.3 Cl.1, Cl.2, and Gr.4N Low Alloy Steels for Pressure Vessels

Energy Technology Data Exchange (ETDEWEB)

Kim, Min-Chul; Park, Sang-Gyu; Lee, Bong-Sang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, Ki-Hyoung [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2014-10-15

In this study, microstructure and mechanical properties of SA508 Gr.3 Cl. 1, Cl.2, and Gr.4N low alloy steels are characterized to compare their properties. To evaluate the fracture toughness in the transition region, the master curve method according to ASTM E1921 was adopted in the cleavage transition region. Tensile tests and Charpy impact tests were also performed to evaluate the mechanical properties, and a microstructural investigation was carried out. The microstructure and mechanical properties of SA508 Gr.3 Cl.1, Cl2 and Gr.4N low alloy steels were characterized.. The predominant microstructure of SA508 Gr.4N model alloy is tempered martensite, while SA508 Gr.3 Cl.1 and Cl.2 steels show a typical tempered upper bainitic structure. SA508 Gr. 4N model alloy shows the best strength and transition behavior among the three SA508 steels. SA508 Gr.3 Cl.2 steel also has quite good strength, but there is a loss of toughness.

7 CFR 1900.155 - Designating the processing/servicing official.

Science.gov (United States)

2010-01-01

... 7 Agriculture 12 2010-01-01 2010-01-01 false Designating the processing/servicing official. 1900.155 Section 1900.155 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE SERVICE, RURAL UTILITIES SERVICE, AND FARM SERVICE AGENCY...

Phase Constituents and Microstructure of Ti3Al/Fe3Al + TiN/TiB2 Composite Coating on Titanium Alloy

Science.gov (United States)

Li, Jianing; Chen, Chuanzhong; Zhang, Cuifang

Laser cladding of the Fe3Al + B4C/TiN + Al2O3 pre-placed powders on the Ti-6Al-4V alloy can form the Ti3Al/Fe3Al + TiN/TiB2 composite coating, which improved the wear resistance of the Ti-6Al-4V alloy surface. In this study, the Ti3Al/Fe3Al + TiN/TiB2 composite coating has been researched by means of X-ray diffraction and scanning electron microscope. It was found that during the laser cladding process, Al2O3 can react with TiB2, leading to the formations of Ti3Al and B. This principle can be used to improve the Fe3Al + B4C/TiN laser-cladded coating on the Ti-6Al-4V alloy. Furthermore, during the cladding process, C consumed the oxygen in Fe3Al + B4C /TiN + Al2O3 molten pool, which retarded the productions of the redundant metal oxides.

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

International Nuclear Information System (INIS)

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

1978-01-01

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

Structural and electronic properties of Ga{sub 1-x}In{sub x} As{sub 1-y}N{sub y} quaternary semiconductor alloy on GaAs substrate

Energy Technology Data Exchange (ETDEWEB)

Aslan, Metin, E-mail: maslan@sakarya.edu.tr [Sakarya University, Art, Science Faculty, Department of Physics, Esentepe Campus, 54187 Sakarya (Turkey); Yalc Latin-Small-Letter-Dotless-I n, Battal G.; Uestuendag, Mehmet [Sakarya University, Art, Science Faculty, Department of Physics, Esentepe Campus, 54187 Sakarya (Turkey)

2012-04-05

Highlights: Black-Right-Pointing-Pointer In this study we used DFT in the frame of LDA approach to determine electronic and structural properties of GaInAsN alloy. Black-Right-Pointing-Pointer We calculated lattice parameter and band gap energy of binary (GaAs, InAs, and GaN), ternary (GaInAs, GaAsN) and quaternary (GaInAsN) semiconductor alloys. Black-Right-Pointing-Pointer We formulated lattice parameter of GaInAsN respect to In and N composition. Black-Right-Pointing-Pointer We investigated different In and N composition of GaInAsN/GaAs heterostructure for various device applications. - Abstract: We have presented structural and electronic properties of binary (GaAs, GaN and InAs), ternary (Ga{sub 1-x}In{sub x}As and GaAs{sub 1-y}N{sub y}) and quaternary (Ga{sub 1-x}In{sub x}As{sub 1-y}N{sub y}) semiconductor alloys by using a first-principles pseudopotential technique. The structural and electronic properties of Zinc-Blende phase of these materials have been calculated by using the local density approximation (LDA) of the density-functional theory (DFT). To obtain the lattice parameter and band gap energy of the (GaInAsN) quaternary semiconductor alloy we separately calculated the lattice constant and band gap energies of ternary semiconductor alloys, namely GaAsN and GaInAs. The calculated lattice constant, bulk modulus and the direct band gaps for studied semiconductors showed great parallelism with the previous available theoretical and experimental studies.

MicroRNA-155 is upregulated in ascites in patients with spontaneous bacterial peritonitis

DEFF Research Database (Denmark)

Lutz, Philipp; M'haimid, Mohamed; Pohlmann, Alessandra

2017-01-01

, sex or aetiology of cirrhosis. MiR-125b levels differed between patients with low and high MELD score, and miR-125b levels showed an inverse correlation to serum creatinine (r 2 = â '0.23; p = 0.05). MiR-155 was elevated in patients with spontaneous bacterial peritonitis (SBP) (n = 10; p = 0.04). Mi...

Heat treatment effects on structure and proerties of the alloy type KhN73MBNYu (EhJ 698)

International Nuclear Information System (INIS)

Maslenkov, S.B.; Maslenkova, E.A.; Solov'ev, Yu.V.; Zryumov, V.P.

1994-01-01

Influence of quenching temperature and various ageing conditions on tensile properties and impact strength of wrought alloy type KhN73MBTYu has been investigated at room temperature and in the range of 500-850 deg C. Two-step quenching followed by ageing at 700-750 deg C. Two-step quenching followed by ageing at 700-750 deg C is shown to assure needed heat resistance of the alloy. Due to the whole complex of structural changes during heat treatments mechanical properties of the alloy preserv high level up to 750 deg C. This temperature is limiting value in the case of long-term operation

Cast thermally stable high temperature nickel-base alloys and casting made therefrom

International Nuclear Information System (INIS)

Acuncius, D.A.; Herchenroeder, R.B.; Kirchner, R.W.; Silence, W.L.

1977-01-01

A cast thermally stable high temperature nickel-base alloy characterized by superior oxidation resistance, sustainable hot strength and retention of ductility on aging is provided by maintaining the alloy chemistry within the composition molybdenum 13.7% to 15.5%; chromium 14.7% to 16.5%; carbon up to 0.1%, lanthanum in an effective amount to provide oxidation resistance up to 0.08%; boron up to 0.015%; manganese 0.3% to 1.0%; silicon 0.2% to 0.8%; cobalt up to 2.0%; iron up to 3.0%; tungsten up to 1.0%; copper up to 0.4%; phosphorous up to 0.02%; sulfur up to 0.015%; aluminum 0.1% to 0.5% and the balance nickel while maintaining the Nv number less than 2.31

49 CFR 38.155 - Interior circulation, handrails and stanchions.

Science.gov (United States)

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Interior circulation, handrails and stanchions. 38.155 Section 38.155 Transportation Office of the Secretary of Transportation AMERICANS WITH... passenger from the door through the boarding procedure. Passengers shall be able to lean against the assist...

Physical and welding metallurgy of Gd-enriched austenitic alloys for spent nuclear fuel applications. Part II, nickel base alloys

International Nuclear Information System (INIS)

Mizia, Ronald E.; Michael, Joseph Richard; Williams, David Brian; Dupont, John Neuman; Robino, Charles Victor

2004-01-01

The physical and welding a metallurgy of gadolinium- (Gd-) enriched Ni-based alloys has been examined using a combination of differential thermal analysis, hot ductility testing. Varestraint testing, and various microstructural characterization techniques. Three different matrix compositions were chosen that were similar to commercial Ni-Cr-Mo base alloys (UNS N06455, N06022, and N06059). A ternary Ni-Cr-Gd alloy was also examined. The Gd level of each alloy was ∼2 wt-%. All the alloys initiated solidification by formation of primary austenite and terminated solidification by a Liquid γ + Ni 5 Gd eutectic-type reaction at ∼1270 C. The solidification temperature ranges of the alloys varied from ∼100 to 130 C (depending on alloy composition). This is a substantial reduction compared to the solidification temperature range to Gd-enriched stainless steels (360 to 400 C) that terminate solidification by a peritectic reaction at ∼1060 C. The higher-temperature eutectic reaction that occurs in the Ni-based alloys is accompanied by significant improvements in hot ductility and solidification cracking resistance. The results of this research demonstrate that Gd-enriched Ni-based alloys are excellent candidate materials for nuclear criticality control in spent nuclear fuel storage applications that require production and fabrication of large amounts of material through conventional ingot metallurgy and fusion welding techniques

Aluminium EN AW-2124 alloy matrix composites reinforced with Ti(C,N), BN and Al2O3 particles

International Nuclear Information System (INIS)

Dobrzanski, L.A.; Wlodarczyk, A.; Adamiak, M.

2003-01-01

Investigation results of the aluminium alloy EN AW-2124 matrix composite materials with particles of the powders Ti(C,N), BN and Al 2 O 3 (15 wt.%) are presented in the paper. In order to obtain uniform distribution of reinforcement particles in aluminium alloy matrix powders of composite components have been milled in the rotary ball-bearing pulverizer. The composites have been pressed in laboratory vertical press at room temperature under the pressure of 500 kN. Obtained die samplings have been heated to the temperature 520-550 o C and extruded. Bars of diameter 8 mm have been received as a final product. Metallographic examination of the composites materials' structure shows non-uniform distribution of reinforced powders in the aluminium alloy matrix banding of reinforcements particles corresponds to the extrusion direction. Particles of reinforcement distribution in aluminium alloy matrix is irregular, some agglomerations of powder of aluminium oxide and porosity of different size have been noticed. Investigations of hardness and ultimate compressive strength show that the particles of reinforcement improve mechanical properties of composite materials. Investigations of compressive strength, carried out at room temperature, enable to compare mechanical properties of matrix and composite. (author)

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

International Nuclear Information System (INIS)

Sadov, I.I.

1982-01-01

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

INFLUENCE OF MECHANICAL ALLOYING AND LEAD CONTENT ON MICROSTRUCTURE, HARDNESS AND TRIBOLOGICAL BEHAVIOR OF 6061 ALUMINIUM ALLOYS

Directory of Open Access Journals (Sweden)

M. Paidpilli

2017-03-01

Full Text Available In the present work, one batch of prealloyed 6061Al powder was processed by mixing and another one was ball milled with varying amount of lead content (0-15 vol. %. These powders were compacted at 300MPa and sintered at 590˚C under N2. The instrumented hardness and the young’s modulus of as-sintered 6061Al-Pb alloys were examined as a function of lead content and processing route. The wear test under dry sliding condition has been performed at varying loads (10-40 N using pin-on-disc tribometer. The microstructure and worn surfaces have been investigated using SEM to evaluate the change in topographical features due to mechanical alloying and lead content. The mechanically alloyed materials showed improved wear characteristics as compared to as-mixed counterpart alloys. Delamination of 6061Al-Pb alloys decreases up to an optimum lead composition in both as-mixed and ball-milled 6061Al-Pb alloys. The results indicated minimum wear rate for as-mixed and ball-milled 6061Al alloy at 5 and 10 vol. % Pb, respectively.

In vitro bio-functional performances of the novel superelastic beta-type Ti–23Nb–0.7Ta–2Zr–0.5N alloy

International Nuclear Information System (INIS)

Ion, Raluca; Gordin, Doina-Margareta; Mitran, Valentina; Osiceanu, Petre; Dinescu, Sorina; Gloriant, Thierry; Cimpean, Anisoara

2014-01-01

The materials used for internal fracture fixations and joint replacements are mainly made of metals which still face problems ranging from higher rigidity than that of natural bone to leaching cytotoxic metallic ions. Beta (β)-type titanium alloys with low elastic modulus made from non-toxic and non-allergenic elements are desirable to reduce stress shielding effect and enhance bone remodeling. In this work, a new β-type Ti–23Nb–0.7Ta–2Zr–0.5N alloy with a Young's modulus of approximately 50 GPa was designed and characterized. The behavior of MC3T3-E1 pre-osteoblasts on the new alloy, including adhesion, proliferation and differentiation, was evaluated by examining the cytoskeleton, focal adhesion formation, metabolic activity and extracellular matrix mineralization. Results indicated that the pre-osteoblast cells exhibited a similar degree of attachment and growth on Ti–23Nb–0.7Ta–2Zr–0.5N and Ti–6Al–4V. However, the novel alloy proved to be significantly more efficient in sustaining mineralized matrix deposition upon osteogenic induction of the cells than Ti–6Al–4V control. Further, the analysis of RAW 264.7 macrophages cytokine gene and protein expression indicated no significant inflammatory response. Collectively, these findings suggest that the Ti–23Nb–0.7Ta–2Zr–0.5N alloy, which has an increased mechanical biocompatibility with bone, allows a better osteogenic differentiation of osteoblast precursor cells than Ti–6Al–4V and holds great potential for future clinical prosthetic applications. - Highlights: • A new low modulus (∼ 50 GPa) β-type Ti–23Nb–0.7Ta–2Zr–0.5N alloy was synthesized. • In vitro response of MC3T3-E1 pre-osteoblasts and RAW 264.7 macrophages was studied. • Cellular response to Ti–23Nb–0.7Ta–2Zr–0.5N and Ti6Al4V was almost identical. • Ti–23Nb–0.7Ta–2Zr–0.5N alloy is more efficient in sustaining matrix mineralization. • No significant inflammatory response was

In vitro bio-functional performances of the novel superelastic beta-type Ti–23Nb–0.7Ta–2Zr–0.5N alloy

Energy Technology Data Exchange (ETDEWEB)

Ion, Raluca [University of Bucharest, Department of Biochemistry and Molecular Biology, 91–95 Spl. Independentei, 050095, Bucharest (Romania); Gordin, Doina-Margareta [INSA Rennes, UMR CNRS 6226 SCR/Chimie-Métallurgie, 20 avenue des Buttes de Coësmes, F-35043 Rennes Cedex (France); Mitran, Valentina [University of Bucharest, Department of Biochemistry and Molecular Biology, 91–95 Spl. Independentei, 050095, Bucharest (Romania); Osiceanu, Petre [Institute of Physical Chemistry “Ilie Murgulescu”, 202 Spl. Independentei, 060021 Bucharest (Romania); Dinescu, Sorina [University of Bucharest, Department of Biochemistry and Molecular Biology, 91–95 Spl. Independentei, 050095, Bucharest (Romania); Gloriant, Thierry [INSA Rennes, UMR CNRS 6226 SCR/Chimie-Métallurgie, 20 avenue des Buttes de Coësmes, F-35043 Rennes Cedex (France); Cimpean, Anisoara, E-mail: anisoara.cimpean@bio.unibuc.ro [University of Bucharest, Department of Biochemistry and Molecular Biology, 91–95 Spl. Independentei, 050095, Bucharest (Romania)

2014-02-01

The materials used for internal fracture fixations and joint replacements are mainly made of metals which still face problems ranging from higher rigidity than that of natural bone to leaching cytotoxic metallic ions. Beta (β)-type titanium alloys with low elastic modulus made from non-toxic and non-allergenic elements are desirable to reduce stress shielding effect and enhance bone remodeling. In this work, a new β-type Ti–23Nb–0.7Ta–2Zr–0.5N alloy with a Young's modulus of approximately 50 GPa was designed and characterized. The behavior of MC3T3-E1 pre-osteoblasts on the new alloy, including adhesion, proliferation and differentiation, was evaluated by examining the cytoskeleton, focal adhesion formation, metabolic activity and extracellular matrix mineralization. Results indicated that the pre-osteoblast cells exhibited a similar degree of attachment and growth on Ti–23Nb–0.7Ta–2Zr–0.5N and Ti–6Al–4V. However, the novel alloy proved to be significantly more efficient in sustaining mineralized matrix deposition upon osteogenic induction of the cells than Ti–6Al–4V control. Further, the analysis of RAW 264.7 macrophages cytokine gene and protein expression indicated no significant inflammatory response. Collectively, these findings suggest that the Ti–23Nb–0.7Ta–2Zr–0.5N alloy, which has an increased mechanical biocompatibility with bone, allows a better osteogenic differentiation of osteoblast precursor cells than Ti–6Al–4V and holds great potential for future clinical prosthetic applications. - Highlights: • A new low modulus (∼ 50 GPa) β-type Ti–23Nb–0.7Ta–2Zr–0.5N alloy was synthesized. • In vitro response of MC3T3-E1 pre-osteoblasts and RAW 264.7 macrophages was studied. • Cellular response to Ti–23Nb–0.7Ta–2Zr–0.5N and Ti6Al4V was almost identical. • Ti–23Nb–0.7Ta–2Zr–0.5N alloy is more efficient in sustaining matrix mineralization. • No significant inflammatory response was

29 CFR 1926.155 - Definitions applicable to this subpart.

Science.gov (United States)

2010-07-01

... 29 Labor 8 2010-07-01 2010-07-01 false Definitions applicable to this subpart. 1926.155 Section... § 1926.155 Definitions applicable to this subpart. (a) Approved, for the purpose of this subpart, means... any of the following hydrocarbons, or mixtures of them, such as propane, propylene, butane (normal...

Effect of nitrogen addition on superelasticity of Ti-Zr-Nb alloys

International Nuclear Information System (INIS)

Tahara, Masaki; Kim, Hee Young; Miyazaki, Shuichi; Inamura, Tomonari; Hosoda, Hideki

2008-01-01

Recently, the Ti-Zr-Nb alloys have been developed as Ni-free shape memory and superelastic alloys. In this study, the effect of Nb and nitrogen (N) contents on martensitic transformation behavior, shape memory effect and superelasticity in Ti-18Zr-(12-16)Nb-(0-1.0)N (at%) alloys were investigated using tensile tests, optical microscopy and X-ray diffraction. Shape memory effect was observed in Ti-18Zr-(12-13)Nb and Ti-18Zr-12Nb-0.5N alloys at room temperature. The superelastic behavior appeared by the increase of Nb or N content. The Ti-18Zr-(14-15)Nb, Ti-18Zr-(13-14)Nb-0.5N and Ti-18Zr-(12-14)Nb-1.0N alloys exhibited the superelasticity at room temperature. The martensitic transformation start temperature (M s ) decreased by 75 K with 1 at% increase of N content for Ti-18Zr-13Nb alloy. The critical stress for slip deformation and the stress for inducing the martensitic transformation increased with increasing N content. The superelastic recovery strain was also increased by adding N. The maximum recovery strain of 5.0% was obtained in the Ti-18Zr-14Nb-0.5N alloy. (author)

Microstructure and properties of duplex (Ti:N)-DLC/MAO coating on magnesium alloy

Energy Technology Data Exchange (ETDEWEB)

Yang, Wei; Ke, Peiling [Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Fang, Yong [Sir Run Run Shaw Hospital, School of Medicine, Zhe Jiang University, Zhejiang 310016 (China); Zheng, He [Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Wang, Aiying, E-mail: aywang@nimte.ac.cn [Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

2013-04-01

Ti and N co-doped diamond-like carbon ((Ti:N)-DLC) film was deposited on the MAO coated substrate using a hybrid beam deposition system, which consists of a DC magnetron sputtering of Ti target and a linear ion source (LIS) with C{sub 2}H{sub 2} and N{sub 2} precursor gas. The microstructure and properties of the duplex (Ti:N)-DLC/MAO coating were investigated. Results indicate that the (Ti:N)-DLC top film with TiN crystalline phase was formed. Ti and N co-doping resulted in the increasing I{sub D}/I{sub G} ratio. The significant improvement in the wear and corrosion resistance of duplex (Ti:N)-DLC/MAO coating was mainly attributed to the increased binding strength, lubrication characteristics and chemical inertness of (Ti:N)-DLC top film. The superior low-friction and anti-corrosion properties of duplex (Ti:N)-DLC/MAO coating make it a good candidate as protective coating on magnesium alloy.

Intersubband energies in strain-compensated InGaN/AlInN quantum well structures

Energy Technology Data Exchange (ETDEWEB)

Park, Seoung-Hwan, E-mail: shpark@cu.ac.kr [Department of Electronics Engineering, Catholic University of Daegu, Hayang, Kyeongsan, Kyeongbuk, 712-702 (Korea, Republic of); Ahn, Doyeol [Institute of Quantum Information Processing and Systems, University of Seoul, 90 Jeonnong, Tongdaimoon-Gu, Seoul, Korea 130-743 (Korea, Republic of)

2016-01-15

Intersubband transition energies in the conduction band for strain-compensated InGaN/AlInN quantum well (QW) structures were investigated as a function of strain based on an effective mass theory with the nonparabolicity taken into account. In the case of an InGaN/AlInN QW structure lattice-matched to GaN, the wavelength is shown to be longer than 1.55 μm. On the other hand, strain-compensated QW structures show that the wavelength of 1.55 μm can be reached even for the QW structure with a relatively small strain of 0.3 %. Hence, the strain-compensated QW structures can be used for telecommunication applications at 1.55 μm with a small strain, compared to conventional GaN/AlN QW structure.

Test of E1-radiative strength function and level density models by 155 Gd (n,2γ) 156 Gd reaction

International Nuclear Information System (INIS)

Voinov, A.V.

1996-01-01

The information about the level density of 156 Gd nucleus and strength functions of γ transitions extracted from two γ-cascade spectra of the 155 Gd (n,2γ) 156 Gd reaction is analyzed. The method of statistical simulation of γ-cascade intensity is applied for calculation of the main parameters of experimental spectra. The method is used to extract the information on the E1-radiative strength function of γ transitions and level density in the 156 Gd nucleus. It is shown that at an excitation energy above 3 MeV the level density of 156 Gd nucleus must decrease in comparison with that calculated within the Fermi gas model. Its is concluded that possible explanation of the observed effect is connected with the influence of pairing correlations on the level density in nuclei

Early detection and monitoring of cartilage alteration in the experimental meniscectomised guinea pig model of osteoarthritis by 99mTc-NTP 15-5 scintigraphy

International Nuclear Information System (INIS)

Miot-Noirault, Elisabeth; Vidal, Aurelien; Bonafous, Jacques; Audin, Laurent; Madelmont, Jean-Claude; Moins, Nicole; Pastoureau, Philippe; Chomel, Agnes; Sarry, Laurent

2007-01-01

This study in the meniscectomised guinea pig aimed to demonstrate that the radiotracer 99m Tc-NTP 15-5 would have pathophysiological validity for in vivo osteoarthritis imaging. The specificity of 99m Tc-NTP 15-5 for cartilage was determined in healthy animals (n = 13), by tissue radioactivity counting, joint autoradiography and scintigraphy. 99m Tc-NTP 15-5 scintigraphy was performed at 20, 50, 80, 115, 130, 150 and 180 days after medial meniscectomy (n = 10 MNX) or sham operation (n = 5), and scintigraphic ratios (operated/contralateral) were calculated for femoral (F) and tibial (T) areas. F and T ratios were compared with those of 99m Tc-MDP bone scintigraphy. At the study end-point, autoradiographic analysis of joint 99m Tc-NTP 15-5 distribution and macroscopic scoring of cartilage integrity were performed. The high and specific accumulation of 99m Tc-NTP 15-5 in normal cartilage (about 5.5 ± 1.7 % of injected dose/g of tissue), which permitted joint imaging with high contrast, was affected by osteoarthritis. In the MNX group, 99m Tc-NTP 15-5 accumulation in cartilage within the operated joint, relative to the contralateral joint, was observed to change in the same animals as pathology progressed. Although F and T ratios were significantly higher in MNX (F = 1.7 ± 0.2; T = 1.6 ± 0.1) than in shams (F = 1.0 ± 0.1; T = 1.0 ± 0.1) at day 50, they were significantly lower in MNX (F = 0.6 ± 0.1; T = 0.7 ± 0.1) than in shams (F = 1.0 ± 0.1; T = 0.9 ± 0.1) at day 180. No change in 99m Tc-MDP uptake was observed over 6 months. Macroscopic analysis confirmed features of osteoarthritis only in MNX knees. These results in MNX guinea pigs provide additional support for the use of 99m Tc-NTP 15-5 for in vivo imaging of osteoarthritis. (orig.)

Effects of Plasma ZrN Metallurgy and Shot Peening Duplex Treatment on Fretting Wear and Fretting Fatigue Behavior of Ti6Al4V Alloy.

Science.gov (United States)

Tang, Jingang; Liu, Daoxin; Zhang, Xiaohua; Du, Dongxing; Yu, Shouming

2016-03-23

A metallurgical zirconium nitride (ZrN) layer was fabricated using glow metallurgy using nitriding with zirconiuming prior treatment of the Ti6Al4V alloy. The microstructure, composition and microhardness of the corresponding layer were studied. The influence of this treatment on fretting wear (FW) and fretting fatigue (FF) behavior of the Ti6Al4V alloy was studied. The composite layer consisted of an 8-μm-thick ZrN compound layer and a 50-μm-thick nitrogen-rich Zr-Ti solid solution layer. The surface microhardness of the composite layer is 1775 HK 0.1 . A gradient in cross-sectional microhardness distribution exists in the layer. The plasma ZrN metallurgical layer improves the FW resistance of the Ti6Al4V alloy, but reduces the base FF resistance. This occurs because the improvement in surface hardness results in lowering of the toughness and increasing in the notch sensitivity. Compared with shot peening treatment, plasma ZrN metallurgy and shot peening composite treatment improves the FW resistance and enhances the FF resistance of the Ti6Al4V alloy. This is attributed to the introduction of a compressive stress field. The combination of toughness, strength, FW resistance and fatigue resistance enhance the FF resistance for titanium alloy.

Influence of the S/N ratio on the corrosion release of Alloy 690 tubes in a primary coolant

International Nuclear Information System (INIS)

Shim, Hee-Sang; Choi, Myung Sik; Kim, Kyung Mo; Seo, Myung Ji; Hur, Do Haeng; Choi, Tack-Sang; Yoo, One

2014-01-01

Alloy 690TT is a promising steam generator (SG) tube material of a pressurized water reactor due to its excellent resistance to stress corrosion cracking (SCC) that has caused problems in Alloy 600 as an old SG tube material. The qualities of this material have been managed thoroughly from manufacturing step under various specification regulations as well as in in-service step. For examples, the surface roughness are prescribed as the values less than 1.6 μm for the tube outside and 0.5 μm for the inside, respectively. In addition, the surface state and defect must be qualified through the eddy current test (ECT) and the ultrasonic test (UT) according to the ASME Section III, NB2550. Then, the signal-to-noise (S/N) ratio, which is measured using ECT bobbin probe, is the important criteria to determine the material and it shall be 15 to 1 or higher at the standard frequency for any fixed 0.5 m length of any tube. The corrosion behaviours of the Alloy 690TT under high-temperature pressurized primary water have been studied widely in a point of the SCC but discussed narrowly in a point of the corrosion release. In particular, the effect of the S/N ratio on the corrosion release of this material surface has been rarely investigated. In this work, we evaluate the influence of the S/N ratio on the corrosion release of Alloy 690 SG tubes. The specimens with different S/N ratio were selected through ECT bobbin inspection and a corrosion release test was conducted using a simulated primary circulation loop. The material properties and oxidation behaviours were investigated by surface profiler, scanning electron microscopy, transmission electron microscopy, grazing incidence X-ray diffraction and etc. As a result, the corrosion rate was matched preferably with the MRPC characteristics showing macroscopic surface state rather than with the bobbin S/N ratio results. (author)

Comparison of SA508 Gr.3 and SA508 Gr.4N Low Alloy Steels for Reactor Pressure Vessel Steel

Energy Technology Data Exchange (ETDEWEB)

Kim, Min Chul; Lee, B. S

2009-12-15

The microstructural characteristics and mechanical properties of SA508 Gr.3 Mn-Mo-Ni low alloy steel and SA508 Gr.4N Ni-Mo-Cr low alloy steel were investigated. The differences in the stable phases between these two low alloy steels were evaluated by means of a thermodynamic calculation using ThermoCalc. They were then compared to microstructural features and correlated with mechanical properties. Mn-Mo-Ni low alloy steel shows the upper bainite structure which has the coarse cementite in the lath boundaries. However, Ni-Mo-Cr low alloy steel shows the mixture of lower bainite and tempered martensite structure that homogeneously precipitates the small carbides such as M{sub 23}C{sub 6} and M{sub 7}C{sub 3} due to an increase of hardenability and Cr addition. In the mechanical properties, Ni-Mo-Cr low alloy steel has higher strength and toughness than Mn-Mo-Ni low alloy steel. Ni and Cr additions increase the strength by solid solution hardening. Besides, microstructural changes from upper bainite to tempered martensite improve the strength of the low alloy steel by grain refining effect. And the changes in the precipitation behavior by Cr addition improve the ductile-brittle transition behavior along with a toughening effect of Ni addition.

MicroRNA-155 promotes autophagy to eliminate intracellular mycobacteria by targeting Rheb.

Science.gov (United States)

Wang, Jinli; Yang, Kun; Zhou, Lin; Minhaowu; Wu, Yongjian; Zhu, Min; Lai, Xiaomin; Chen, Tao; Feng, Lianqiang; Li, Meiyu; Huang, Chunyu; Zhong, Qiu; Huang, Xi

2013-01-01

Mycobacterium tuberculosis is a hard-to-eradicate intracellular pathogen that infects one-third of the global population. It can live within macrophages owning to its ability to arrest phagolysosome biogenesis. Autophagy has recently been identified as an effective way to control the intracellular mycobacteria by enhancing phagosome maturation. In the present study, we demonstrate a novel role of miR-155 in regulating the autophagy-mediated anti-mycobacterial response. Both in vivo and in vitro studies showed that miR-155 expression was significantly enhanced after mycobacterial infection. Forced expression of miR-155 accelerated the autophagic response in macrophages, thus promoting the maturation of mycobacterial phagosomes and decreasing the survival rate of intracellular mycobacteria, while transfection with miR-155 inhibitor increased mycobacterial survival. However, macrophage-mediated mycobacterial phagocytosis was not affected after miR-155 overexpression or inhibition. Furthermore, blocking autophagy with specific inhibitor 3-methyladenine or silencing of autophagy related gene 7 (Atg7) reduced the ability of miR-155 to promote autophagy and mycobacterial elimination. More importantly, our study demonstrated that miR-155 bound to the 3'-untranslated region of Ras homologue enriched in brain (Rheb), a negative regulator of autophagy, accelerated the process of autophagy and sequential killing of intracellular mycobacteria by suppressing Rheb expression. Our results reveal a novel role of miR-155 in regulating autophagy-mediated mycobacterial elimination by targeting Rheb, and provide potential targets for clinical treatment.

MicroRNA-155 promotes autophagy to eliminate intracellular mycobacteria by targeting Rheb.

Directory of Open Access Journals (Sweden)

Jinli Wang

Full Text Available Mycobacterium tuberculosis is a hard-to-eradicate intracellular pathogen that infects one-third of the global population. It can live within macrophages owning to its ability to arrest phagolysosome biogenesis. Autophagy has recently been identified as an effective way to control the intracellular mycobacteria by enhancing phagosome maturation. In the present study, we demonstrate a novel role of miR-155 in regulating the autophagy-mediated anti-mycobacterial response. Both in vivo and in vitro studies showed that miR-155 expression was significantly enhanced after mycobacterial infection. Forced expression of miR-155 accelerated the autophagic response in macrophages, thus promoting the maturation of mycobacterial phagosomes and decreasing the survival rate of intracellular mycobacteria, while transfection with miR-155 inhibitor increased mycobacterial survival. However, macrophage-mediated mycobacterial phagocytosis was not affected after miR-155 overexpression or inhibition. Furthermore, blocking autophagy with specific inhibitor 3-methyladenine or silencing of autophagy related gene 7 (Atg7 reduced the ability of miR-155 to promote autophagy and mycobacterial elimination. More importantly, our study demonstrated that miR-155 bound to the 3'-untranslated region of Ras homologue enriched in brain (Rheb, a negative regulator of autophagy, accelerated the process of autophagy and sequential killing of intracellular mycobacteria by suppressing Rheb expression. Our results reveal a novel role of miR-155 in regulating autophagy-mediated mycobacterial elimination by targeting Rheb, and provide potential targets for clinical treatment.

Effects of Alloyed Carbon on the General Corrosion and the Pitting Corrosion Behavior of FeCrMnN Stainless Steels

Energy Technology Data Exchange (ETDEWEB)

Ha, Heon-Young; Lee, Tae-Ho; Kim, Sung-Joon [Korea Institute of Materials Science, Changwon (Korea, Republic of)

2011-10-15

The effects of alloyed carbon on the pitting corrosion, the general corrosion, and the passivity behavior of Fe{sub 1}8Cr{sub 1}0Mn{sub 0}.4Nx{sub C} (x=0 ⁓ 0.38 wt%) alloys were investigated by various electrochemical methods and XPS analysis. The alloyed carbon increased the general corrosion resistance of the FeCrMnN matrix. Carbon enhanced the corrosion potential, reduced the metal dissolution rate, and accelerated the hydrogen evolution reaction rate in various acidic solutions. In addition, carbon promoted the pitting corrosion resistance of the matrix in a chloride solution. The alloyed carbon in the matrix increased the chromium content in the passive film, and thus the passive film became more protective.

Preferential Au precipitation at deformation-induced defects in Fe–Au and Fe–Au–B–N alloys

Energy Technology Data Exchange (ETDEWEB)

Zhang, S., E-mail: S.Zhang-1@tudelft.nl [Fundamental Aspects of Materials and Energy, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands); Langelaan, G. [Fundamental Aspects of Materials and Energy, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands); Brouwer, J.C.; Sloof, W.G. [Department of Materials Science and Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft (Netherlands); Brück, E. [Fundamental Aspects of Materials and Energy, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands); Zwaag, S. van der [Novel Aerospace Materials Group, Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS Delft (Netherlands); Dijk, N.H. van [Fundamental Aspects of Materials and Energy, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands)

2014-01-25

Highlights: • Fe–Au–B–N forms a good model alloy system for self healing of deformation damage. • Solute Au atoms exclusively precipitate at grain boundaries, cracks and cavities. • XPS indicates a strong tendency for Au segregation on free surfaces at 550 °C. • Interstitial B and N form hexagonal BN on free surfaces at 550 °C. • Selective Au precipitation at open volume defects can cause autonomous repair. -- Abstract: The influence of deformation-induced defects on the isothermal precipitation of Au was studied in high-purity Fe–Au and Fe–Au–B–N alloys. Preferential Au precipitation upon annealing at 550 °C is observed at local plastic indentations. In fractured Fe–Au–B–N, solute Au atoms were found to heterogeneously precipitate at grain boundaries and local micro-cracks. This is supported by in-situ creep tests that showed a strong tendency for Au precipitation at cracks and cavities also formed during creep loading at 550 °C. Complementary X-ray photoelectron spectroscopy experiments indicate a strong tendency of Au, B and N segregation onto free surface during aging. The observed site-specific precipitation of Au holds interesting opportunities for defect healing in steels subjected to creep deformation.

Cryo-EM of the pathogenic VCP variant R155P reveals long-range conformational changes in the D2 ATPase ring

Energy Technology Data Exchange (ETDEWEB)

Mountassif, Driss; Fabre, Lucien [Department of Anatomy and Cell Biology, McGill University, Groupe de recherche axé sur la structure des protéines (GRASP), Groupe d' Étude des Proteines Membranaires (GÉPROM), 3640 University Street, Montreal H3A 0C7 (Canada); Zaid, Younes [Department of Anatomy and Cell Biology, McGill University, Groupe de recherche axé sur la structure des protéines (GRASP), Groupe d' Étude des Proteines Membranaires (GÉPROM), 3640 University Street, Montreal H3A 0C7 (Canada); Current address: Laboratory of Thrombosis and Hemostasis, Montreal Heart Institute, Montreal, Quebec (Canada); Halawani, Dalia [Department of Anatomy and Cell Biology, McGill University, Groupe de recherche axé sur la structure des protéines (GRASP), Groupe d' Étude des Proteines Membranaires (GÉPROM), 3640 University Street, Montreal H3A 0C7 (Canada); Current address: Department of Cell Biology, Lerner Research Institute, 9500 Euclid Avenue NC10, Cleveland, OH 44195 (United States); Rouiller, Isabelle, E-mail: isabelle.rouiller@mcgill.ca [Department of Anatomy and Cell Biology, McGill University, Groupe de recherche axé sur la structure des protéines (GRASP), Groupe d' Étude des Proteines Membranaires (GÉPROM), 3640 University Street, Montreal H3A 0C7 (Canada)

2015-12-25

Single amino acid mutations in valosin containing protein (VCP/p97), a highly conserved member of the ATPases associated with diverse cellular activities (AAA) family of ATPases has been linked to a severe degenerative disease affecting brain, muscle and bone tissue. Previous studies have demonstrated the role of VCP mutations in altering the ATPase activity of the D2 ring; however the structural consequences of these mutations remain unclear. In this study, we report the three-dimensional (3D) map of the pathogenic VCP variant, R155P, as revealed by single-particle Cryo-Electron Microscopy (EM) analysis at 14 Å resolution. We show that the N-terminal R155P mutation induces a large structural reorganisation of the D2 ATPase ring. Results from docking studies using crystal structure data of available wild-type VCP in the EM density maps indicate that the major difference is localized at the interface between two protomers within the D2 ring. Consistent with a conformational change, the VCP R155P variant shifted the isoelectric point of the protein and reduced its interaction with its well-characterized cofactor, nuclear protein localization-4 (Npl4). Together, our results demonstrate that a single amino acid substitution in the N-terminal domain can relay long-range conformational changes to the distal D2 ATPase ring. Our results provide the first structural clues of how VCP mutations may influence the activity and function of the D2 ATPase ring. - Highlights: • p97{sub R155P} and p97{sub A232E} decrease the ability of p97 to bind to its co-factor Npl4. • p97{sub R155P} has a different isoelectric point than that of p97{sub R95G}, p97{sub A232E} and p97{sub WT}. • Mutation R155P changes principally the conformation of the D2 ring. • Mutation R155P modifies the interface between two protomers within the D2 ring.

Cryo-EM of the pathogenic VCP variant R155P reveals long-range conformational changes in the D2 ATPase ring

International Nuclear Information System (INIS)

Mountassif, Driss; Fabre, Lucien; Zaid, Younes; Halawani, Dalia; Rouiller, Isabelle

2015-01-01

Single amino acid mutations in valosin containing protein (VCP/p97), a highly conserved member of the ATPases associated with diverse cellular activities (AAA) family of ATPases has been linked to a severe degenerative disease affecting brain, muscle and bone tissue. Previous studies have demonstrated the role of VCP mutations in altering the ATPase activity of the D2 ring; however the structural consequences of these mutations remain unclear. In this study, we report the three-dimensional (3D) map of the pathogenic VCP variant, R155P, as revealed by single-particle Cryo-Electron Microscopy (EM) analysis at 14 Å resolution. We show that the N-terminal R155P mutation induces a large structural reorganisation of the D2 ATPase ring. Results from docking studies using crystal structure data of available wild-type VCP in the EM density maps indicate that the major difference is localized at the interface between two protomers within the D2 ring. Consistent with a conformational change, the VCP R155P variant shifted the isoelectric point of the protein and reduced its interaction with its well-characterized cofactor, nuclear protein localization-4 (Npl4). Together, our results demonstrate that a single amino acid substitution in the N-terminal domain can relay long-range conformational changes to the distal D2 ATPase ring. Our results provide the first structural clues of how VCP mutations may influence the activity and function of the D2 ATPase ring. - Highlights: • p97 R155P and p97 A232E decrease the ability of p97 to bind to its co-factor Npl4. • p97 R155P has a different isoelectric point than that of p97 R95G , p97 A232E and p97 WT . • Mutation R155P changes principally the conformation of the D2 ring. • Mutation R155P modifies the interface between two protomers within the D2 ring.

Di-n-butylamine as an inhibitor for the corrosion of aluminium alloys in hydrochloric acid solutions

Energy Technology Data Exchange (ETDEWEB)

Unni, V K.V.; Rama Char, T L

1965-01-01

Di-n-butylamine is a satisfactory inhibitor for the corrosion of aluminum-manganese alloy in hydrochloric acid solutions. Polarization studies indicate that the anode polarization is negligible, whereas the cathode polarization is appreciable and is increased by the inhibitor. The Tafel plot holds good in this case. The dissolution of the metal is electrochemical in character; the corrosion process appears to be under cathodic control. The efficiency increases with time, the effect being quite significant up to about 3 hr. It increases with increases in concentration of the inhibitor up to a certain value beyond which it is constant. The values increase with acid concentration up to 1.25 N., and remain practically unchanged thereafter. An acid concentration of 1.25 N. and an inhibitor concentration of 0.5 g per liter of nitrogen can be regarded as the optimum from the viewpoint of efficiency, the value being in the range 57-84%. The efficiency of the inhibitor for the aluminum-manganese alloy is about the same order as for pure aluminum. (10 refs.)

Neutron irradiation effects on mechanical properties in SA508 Gr4N high strength low alloy steel

International Nuclear Information System (INIS)

Kim, Minchul; Lee, Kihyoung; Park, Sanggyu; Choi, Kwonjae; Lee, Bongsang

2012-01-01

The Reactor Pressure Vessel (RPV) is the key component in determining the lifetime of nuclear power plants because it is subject to the significant aging degradation by irradiation and thermal aging, and there is no practical method for replacing that component. Advanced reactors with much larger capacity than current reactor require the usage of higher strength materials inevitably. The SA508 Gr.4N Ni Cr Mo low alloy steel, in which Ni and Cr contents are larger than in conventional RPV steels, could be a promising RPV material offering improved strength and toughness from its tempered martensitic microstructure. For a structural integrity of RPV, the effect of neutron irradiation on the material property is one of the key issues. The RPV materials suffer from the significant degradation of transition properties by the irradiation embrittlement when its strength is increased by a hardening mechanism. Therefore, the potential for application of SA508 Gr.4N steel as the structural components for nuclear power reactors depends on its ability to maintain adequate transition properties against the operating neutron does. However, it is not easy to fine the data on the irradiation effect on the mechanical properties of SA508 Gr.4N steel. In this study, the irradiation embrittlement of SA508 Gr.4N Ni Cr Mo low alloy steel was evaluated by using specimens irradiated in research reactor. For comparison, the variations of mechanical properties by neutron irradiation for commercial SA508 Gr.3 Mn Mo Ni low alloy steel were also evaluated

40 CFR 155.40 - General.

Science.gov (United States)

2010-07-01

... does not apply to products whose sale or distribution is authorized under FIFRA section 5 or section 18... STANDARDS AND REGISTRATION REVIEW Registration Review Procedures § 155.40 General. (a) Purpose. These regulations establish procedures for the registration review program required in FIFRA section 3(g...

MiR-155 Enhances Insulin Sensitivity by Coordinated Regulation of Multiple Genes in Mice

Science.gov (United States)

Lin, Taoyan; Lin, Xia; Chen, Li; Zeng, Hui; Han, Yanjiang; Wu, Lihong; Huang, Shun; Wang, Meng; Huang, Shenhao; Xie, Raoying; Liang, Liqi; Liu, Yu; Liu, Ruiyu; Zhang, Tingting; Li, Jing; Wang, Shengchun; Sun, Penghui; Huang, Wenhua; Yao, Kaitai; Xu, Kang; Du, Tao; Xiao, Dong

2016-01-01

miR-155 plays critical roles in numerous physiological and pathological processes, however, its function in the regulation of blood glucose homeostasis and insulin sensitivity and underlying mechanisms remain unknown. Here, we reveal that miR-155 levels are downregulated in serum from type 2 diabetes (T2D) patients, suggesting that miR-155 might be involved in blood glucose control and diabetes. Gain-of-function and loss-of-function studies in mice demonstrate that miR-155 has no effects on the pancreatic β-cell proliferation and function. Global transgenic overexpression of miR-155 in mice leads to hypoglycaemia, improved glucose tolerance and insulin sensitivity. Conversely, miR-155 deficiency in mice causes hyperglycemia, impaired glucose tolerance and insulin resistance. In addition, consistent with a positive regulatory role of miR-155 in glucose metabolism, miR-155 positively modulates glucose uptake in all cell types examined, while mice overexpressing miR-155 transgene show enhanced glycolysis, and insulin-stimulated AKT and IRS-1 phosphorylation in liver, adipose tissue or skeletal muscle. Furthermore, we reveal these aforementioned phenomena occur, at least partially, through miR-155-mediated repression of important negative regulators (i.e. C/EBPβ, HDAC4 and SOCS1) of insulin signaling. Taken together, these findings demonstrate, for the first time, that miR-155 is a positive regulator of insulin sensitivity with potential applications for diabetes treatment. PMID:27711113

Phase transition and ductile behavior of IrxOs1-xN alloys from theoretical point of view

Science.gov (United States)

Sarwan, Madhu; Singh, Sadhna

2018-05-01

Present paper reports theoretical investigation of less explored nitrides of Iridium and Osmium using semi-empirical model with charge transfer effect (CTE). This work indicates the presence of structural phase transition in these nitrides from zinc-blend (B3) to rock-salt (B1) structure on application of pressure on them. Transitions occurred at 71 GPa and 86 GPa, with sudden drops in volume of 9.54% and 8.35% in IrN and OsN. The effect of pressure on elastic properties for B3-IrN and B3-OsN is investigated for the first time. On the basis of mechanical properties, it is observed that both compounds are ductile in nature. The present study is extended to investigate transition metal alloy IrxOs1-xN via Vegard's law. To widen the applicability of our model and to explore this alloy we report structural, elastic, mechanical and thermophysical properties. The effect of pressure on Debye temperature with different concentration (x = 0, 0.25, 0.5, 0.75, 1) have also been analyzed. The results are in general in good agreement with available theoretical results.

Electrochemical Evaluation of Hydroxyapatite/ZrN Coated Magnesium Biodegradable Alloy in Ringer Solution as a Simulated Body Fluid

OpenAIRE

Seyed Rahim Kiahosseini; Abdollah Afshar; Majid Mojtahedzadeh Larijani; Mardali Yousefpour

2015-01-01

Magnesium alloys as biodegradable materials can be used in body as an implant materials but since they have poor corrosion resistance, it is required to decrease their corrosion rate by biocompatible coatings. In this study, hydroxyapatite (HA) coatings in the presence of an intermediate layer of ZrN as a biocompatible material, deposited on AZ91 magnesium alloy by ion beam sputtering method at 300 °C temperature and at different times 180, 240, 300, 360 and 420 min. Then changes in corrosion...

Effects of ion-implanted C on the microstructure and surface mechanical properties of Fe alloys implanted with Ti

International Nuclear Information System (INIS)

Follstaedt, D.M.; Knapp, J.A.; Pope, L.E.; Yost, F.G.; Picraux, S.T.

1984-01-01

The microstructural and tribological effects of ion implanting C into Ti-implanted, Fe-based alloys are examined and compared to the influence of C introduced by vacuum carburization during Ti implantation alone. The amorphous surface alloy formed by Ti implantation of pure Fe increases in thickness when additional C is implanted at depths containing Ti but beyond the range of carburization. Pin-on-disc tests of 15-5 PH stainless steel show that implantation of both Ti and C reduces friction significantly under conditions where no reduction is obtained by Ti implantation alone; wear depths are also less when C is implanted. All available experimental results can be accounted for by consideration of the thickness and Ti concentration of the amorphous Fe-Ti-C alloy. The thicker amorphous layer on samples implanted with additional C extends tribological benefits to more severe wear regimes

Preparation of 1 Ci of europium 155 without carrier

International Nuclear Information System (INIS)

Falconi, N.; Radicella, R.

1968-01-01

High activity 'point' sources of 155 Eu are used for medical and industrial applications. For this purpose we have studied a method of obtaining I Ci of carrier free 155 Eu, with a solid residue smaller than 5 mg per Ci. In order to separate the 155 Eu from several grams of a 154 Sm enriched target we propose a procedure which is based on the work of Bouissieres and David, Onstott, and Takekoshi et al. The separation is carried out by electrolysis on a mercury cathode followed by purification on ion exchange resin. The yields of the europium separation and target recovery are 80 per cent and 90 per cent respectively. The time required for the procedure is three days. (authors) [fr

33 CFR 155.200 - Definitions.

Science.gov (United States)

2010-07-01

....200 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION OIL OR HAZARDOUS MATERIAL POLLUTION PREVENTION REGULATIONS FOR VESSELS Vessel Equipment § 155.200... outside the Boundary Lines, as defined in 46 CFR part 7, in any ocean or the Gulf of Mexico; any tank...

33 CFR 155.1010 - Purpose.

Science.gov (United States)

2010-07-01

... OIL OR HAZARDOUS MATERIAL POLLUTION PREVENTION REGULATIONS FOR VESSELS Tank Vessel Response Plans for Oil § 155.1010 Purpose. The purpose of this subpart is to establish requirements for oil spill response plans for certain vessels. The planning criteria in this subpart are intended for use in response...

A graded nano-TiN coating on biomedical Ti alloy: Low friction coefficient, good bonding and biocompatibility.

Science.gov (United States)

Cui, Wenfang; Qin, Gaowu; Duan, Jingzhu; Wang, Huan

2017-02-01

In order to solve wear resistance of Ti alloy biomaterials, the concept of a graded nano-TiN coating has been proposed. The coating was prepared on Ti-6Al-4V bio-alloy by DC reactive magnetron sputtering. The wear performance of the coated specimens was measured in Hank's solution under the load of 10N, and the biocompatibility was evaluated according to ISO-10993-4 standard. The results show that the gradient coating exhibits a gradual change in compositions and microstructures along the direction of film growth. Nano-TiN with the size of several to dozens nanometers and Ti 4 N 3-x transitional phase with variable composition form a graded composite structure, which significantly improves adhesion strength (L c1 =80N, L c2 =120N), hardness (21GPa) and anti-wear performance (6.2×10 -7 mm 3 /Nm). The excellent bonding and wear resistance result from a good match of mechanical properties at substrate/coating interface and the strengthening and toughening effects of the nanocrystalline composite. The nano-TiN coating has also been proved to have good biocompatibility through in-vitro cytotoxicity, hemocompatibility and general toxicity tests. And thus, the proposed graded nano-TiN coating is a good candidate improving wear resistance of many implant medical devices. Copyright © 2016 Elsevier B.V. All rights reserved.

Early detection and monitoring of cartilage alteration in the experimental meniscectomised guinea pig model of osteoarthritis by {sup 99m}Tc-NTP 15-5 scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Miot-Noirault, Elisabeth; Vidal, Aurelien; Bonafous, Jacques; Audin, Laurent; Madelmont, Jean-Claude; Moins, Nicole [UMR 484 INSERM, Rue Montalembert, BP 184, Clermont-Ferrand Cedex (France); Pastoureau, Philippe; Chomel, Agnes [Institut de Recherches Servier, Suresnes (France); Sarry, Laurent [ERI 14 INSERM - Faculte de Medecine, Clermont-Ferrand (France)

2007-08-15

This study in the meniscectomised guinea pig aimed to demonstrate that the radiotracer {sup 99m}Tc-NTP 15-5 would have pathophysiological validity for in vivo osteoarthritis imaging. The specificity of {sup 99m}Tc-NTP 15-5 for cartilage was determined in healthy animals (n = 13), by tissue radioactivity counting, joint autoradiography and scintigraphy. {sup 99m}Tc-NTP 15-5 scintigraphy was performed at 20, 50, 80, 115, 130, 150 and 180 days after medial meniscectomy (n = 10 MNX) or sham operation (n = 5), and scintigraphic ratios (operated/contralateral) were calculated for femoral (F) and tibial (T) areas. F and T ratios were compared with those of {sup 99m}Tc-MDP bone scintigraphy. At the study end-point, autoradiographic analysis of joint {sup 99m}Tc-NTP 15-5 distribution and macroscopic scoring of cartilage integrity were performed. The high and specific accumulation of {sup 99m}Tc-NTP 15-5 in normal cartilage (about 5.5 {+-} 1.7 % of injected dose/g of tissue), which permitted joint imaging with high contrast, was affected by osteoarthritis. In the MNX group, {sup 99m}Tc-NTP 15-5 accumulation in cartilage within the operated joint, relative to the contralateral joint, was observed to change in the same animals as pathology progressed. Although F and T ratios were significantly higher in MNX (F = 1.7 {+-} 0.2; T = 1.6 {+-} 0.1) than in shams (F = 1.0 {+-} 0.1; T = 1.0 {+-} 0.1) at day 50, they were significantly lower in MNX (F = 0.6 {+-} 0.1; T = 0.7 {+-} 0.1) than in shams (F = 1.0 {+-} 0.1; T = 0.9 {+-} 0.1) at day 180. No change in {sup 99m}Tc-MDP uptake was observed over 6 months. Macroscopic analysis confirmed features of osteoarthritis only in MNX knees. These results in MNX guinea pigs provide additional support for the use of {sup 99m}Tc-NTP 15-5 for in vivo imaging of osteoarthritis. (orig.)

Study of the nuclear structure of 155Eu

International Nuclear Information System (INIS)

Genezini, Frederico Antonio

2004-01-01

The 155 Eu nuclide was investigated by the directional angular correlation technique following the β decay of 155 Sm. The angular correlation measurements were carried out using a setup with 4 Ge detectors and a multi parametric data acquisition system. To perform the data analysis a new methodology was developed . The multipole mixing ratios of twenty sixty γ- transitions were determined. Seven of them agreed with the results of earlier angular correlation studies and nineteen obtained for the first time confirmed the multipolarity suggested in earlier electron capture studies. Besides, the spin of the level at 1106.83 keV as well as the parity of the level at 1301.41 keV have also been suggested. The nuclear structure of 155 Eu was discussed successfully in terms of the single particle model using a deformed Woods-Saxon potential plus residual pairing interaction permitting the description of the rotational quasi-proton band heads. (author)

Fabrication of spherical high-nitrogen stainless steel powder alloys by mechanical alloying and thermal plasma spheroidization

Science.gov (United States)

Razumov, Nikolay G.; Wang, Qing Sheng; Popovich, Anatoly A.; Shamshurin, Aleksey I.

2018-04-01

This paper describes the results of experimental studies on the treatment of Fe-23Cr-11Mn-1N high-nitrogen stainless steel powder alloys, synthesized by the mechanical alloying (MA) of elemental powders in the flow of a radio frequency thermal plasma. The as-milled powder with irregular particles were successfully converted into spherical high-nitrogen stainless steel powder alloy. Measurement of the residual nitrogen content in the obtained powder, shown that during the plasma spheroidization process, part of the nitrogen escapes from the alloy.

Preparation of 1 Ci of europium 155 without carrier; Une methode de production d'europium 155 sans entraineur au niveau du curie

Energy Technology Data Exchange (ETDEWEB)

Falconi, N; Radicella, R [Commissariat a l' Energie Atomique, Dir. des Materiaux et Combustibles Nucleaires, Saclay (France). Centre d' Etudes Nucleaires

1968-07-01

High activity 'point' sources of {sup 155}Eu are used for medical and industrial applications. For this purpose we have studied a method of obtaining I Ci of carrier free {sup 155}Eu, with a solid residue smaller than 5 mg per Ci. In order to separate the {sup 155}Eu from several grams of a {sup 154}Sm enriched target we propose a procedure which is based on the work of Bouissieres and David, Onstott, and Takekoshi et al. The separation is carried out by electrolysis on a mercury cathode followed by purification on ion exchange resin. The yields of the europium separation and target recovery are 80 per cent and 90 per cent respectively. The time required for the procedure is three days. (authors) [French] L'obtention de sources ponctuelles de haute activite d'europium-l55 est interessante tant pour des usages medicaux qu'industriels. Nous avons cherche le moyen de preparer en une seule fois, une solution d'un curie d'europium-155 sans entraineur presentant un extrait sec inferieur a 5 mg par curie. En se basant sur des travaux de Bouissieres et Davis, d'Onstott, et de Takekoshi et coll., nous avons mis au point une methode permettant de separer l'europium-155 de sa cible de samarium enrichi en {sup 154}Sm par une electrolyse sur cathode de mercure suivie d'une purification sur resine echangeuse d'ions. Les rendements chimiques de separation de l'europium et de recuperation de la cible de samarium enrichi sont respectivement de 80 pour cent et 90 pour cent. La duree de l'operation est de 3 jours. (auteurs)

Crataegus Special Extract WS 1442 Effects on eNOS and microRNA 155.

Science.gov (United States)

Wang, Xinwen; Liang, Yan; Shi, Jian; Zhu, Hao-Jie; Bleske, Barry E

2018-04-16

Increased expression of microRNA 155 (miR-155) results in a decrease in endothelial nitric oxide synthase (eNOS) expression and impaired endothelial function. Factors that have been shown to increase expression of miR-155 may be mitigated by WS 1442, an extract of hawthorn leaves and flowers ( Crataegus special extract) that contains a range of pharmacologically active substances including oligomeric proanthocyanidins and flavonoids. The purpose of this study is to determine the effect of WS 1442 on the expression of miR-155 and eNOS in the presence of tumor necrosis factor (TNF- α ). Human umbilical vein endothelial cells (HUVECs) were studied after the exposure to TNF- α , with or without simvastatin (positive control) and WS 1442. The expression levels of eNOS, phosphorylated eNOS, and miR-155 in the different HUVEC treatment groups were determined by western blot and quantitative real-time polymerase chain reaction, respectively. To evaluate the effect of WS 1442 on the eNOS activity, the medium and intracellular nitrate/nitrite (NO) concentrations were also analyzed using a colorimetric Griess assay kit. The results demonstrated that TNF- α upregulated miR-155 expression and decreased eNOS expression and NO concentrations. WS 1442 also increased miR-155 expression and decreased eNOS expression but, unlike TNF- α , increased phosphorylated eNOS expression and NO concentrations. Surprisingly, WS 1442 increased miR-155 expression; however, WS 1442 mitigated the overall negative effect of miR-155 on decreasing eNOS expression by increasing expression of phosphorylated eNOS and resulting in an increase in NO concentrations. In the setting where miR-155 may be expressed, WS 1442 may offer vascular protection by increasing the expression of phosphorylated eNOS. Georg Thieme Verlag KG Stuttgart · New York.

Deformation potentials in AlGaN and InGaN alloys and their impact on optical polarization properties of nitride quantum wells

DEFF Research Database (Denmark)

Łepkowski, S. P.; Gorczyca, I.; Stefańska-Skrobas, K.

2013-01-01

The deformation potentials acz−D1, act−D2, D3, D4, and D5 are determined for random AlGaN and InGaN alloys using electronic band structure calculations based on the density functional theory. A sublinear composition dependence is obtained for acz−D1 and D3 in AlGaN, and D3 in InGaN, whereas...... superlinear behavior on composition is found foract−D2, D4, and D5 in AlGaN, and act−D2and D5 in InGaN. The optical polarization properties of nitride quantum wells are very well described by the k·p method when the obtained deformation potentials are included. In m-plane AlGaN/AlN and InGaN/GaN quantum wells...

A new insight into high-strength Ti62Nb12.2Fe13.6Co6.4Al5.8 alloys with bimodal microstructure fabricated by semi-solid sintering.

Science.gov (United States)

Liu, L H; Yang, C; Kang, L M; Qu, S G; Li, X Q; Zhang, W W; Chen, W P; Li, Y Y; Li, P J; Zhang, L C

2016-03-31

It is well known that semi-solid forming could only obtain coarse-grained microstructure in a few alloy systems with a low melting point, such as aluminum and magnesium alloys. This work presents that semi-solid forming could also produce novel bimodal microstructure composed of nanostructured matrix and micro-sized (CoFe)Ti2 twins in a titanium alloy, Ti62Nb12.2Fe13.6Co6.4Al5.8. The semi-solid sintering induced by eutectic transformation to form a bimodal microstructure in Ti62Nb12.2Fe13.6Co6.4Al5.8 alloy is a fundamentally different approach from other known methods. The fabricated alloy exhibits high yield strength of 1790 MPa and plastic strain of 15.5%. The novel idea provides a new insight into obtaining nano-grain or bimodal microstructure in alloy systems with high melting point by semi-solid forming and into fabricating high-performance metallic alloys in structural applications.

ERDA, RBS, TEM and SEM characterization of microstructural evolution in helium-implanted Hastelloy N alloy

Energy Technology Data Exchange (ETDEWEB)

Gao, Jie [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049 (China); Bao, Liangman [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Huang, Hefei, E-mail: huanghefei@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Li, Yan, E-mail: liyan@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Lei, Qiantao [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Institute of Modern Physics, Fudan University, Shanghai 200433 (China); Deng, Qi [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Liu, Zhe; Yang, Guo [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049 (China); Shi, Liqun [Institute of Modern Physics, Fudan University, Shanghai 200433 (China)

2017-05-15

Hastelloy N alloy was implanted with 30 keV, 5 × 10{sup 16} ions/cm{sup 2} helium ions at room temperature, and subsequent annealed at 600 °C for 1 h and further annealed at 850 °C for 5 h in vacuum. Using elastic recoil detection analysis (ERDA) and transmission electron microscopy (TEM), the depth profiles of helium concentration and helium bubbles in helium-implanted Hastelloy N alloy were investigated, respectively. The diffusion of helium and molybdenum elements to surface occurred during the vacuum annealing at 850 °C (5 h). It was also observed that bubbles in molybdenum-enriched region were much larger in size than those in deeper region. In addition, it is worth noting that plenty of nano-holes can be observed on the surface of helium-implanted sample after high temperature annealing by scanning electron microscope (SEM). This observation provides the evidence for the occurrence of helium release, which can be also inferred from the results of ERDA and TEM analysis.

Characteristics of oxidation of low-alloyed chromium in nitrogen tetroxide

International Nuclear Information System (INIS)

Kamenev, A.Ya.; Goncharova, N.V.; Kopets, Z.V.; Tedushin, E.E.

1985-01-01

The effect of N 2 O 4 on corrosion properties of chromium-based alloys is studied. The method of structural materials analysis is described using as an example chromium-based alloys in the flow of chemically active N 2 O 4 at high temperatures. The method has been used to study corrosive behaviour of chromium at temperatures 923, 1073 and 1273 K. The time of exposure amounts up to 140 hours. The wave-like time dependence of mass velocity variation has been observed for all chromium samples under test. The time of the alloy exposure to N 2 O 4 medium and the nature of the alloying affect this dependence. The given metallograhic studies of chromium alloys show complex structure of the surface layer

Effect of water-cooling treatment times on properties of friction stir welded joints of 7N01-T4 aluminum alloy

Science.gov (United States)

Zhang, T. H.; Wang, Y.; Fang, X. F.; Liang, P.; Zhao, Y.; Li, Y. H.; Liu, X. M.

2018-02-01

Due to the deformation caused by residual stress in the welding process, welded components need treatment to reduce welding distortion. In this paper, several different times of flame-heating and water-cooling treatment were subjected to the friction stir welding joints of 15mm thick 7N01P-T4 aluminum alloy sheets to study the microstructure variation of friction stir welding joints of 7N01P-T4 aluminum alloy, and to analyze the effect on micro-hardness, tensile and fracture mechanical properties. This investigation will be helpful to optimize treatment methods and provide instruction on industrial production.

Inhibition of miR-155 Protects Against LPS-induced Cardiac Dysfunction and Apoptosis in Mice

Directory of Open Access Journals (Sweden)

Hui Wang

2016-01-01

Full Text Available Sepsis-induced myocardial dysfunction represents a major cause of death in intensive care units. Dysregulated microRNAs (miR-155 has been implicated in multiple cardiovascular diseases and miR-155 can be induced by lipopolysaccharide (LPS. However, the role of miR-155 in LPS-induced cardiac dysfunction is unclear. Septic cardiac dysfunction in mice was induced by intraperitoneal injection of LPS (5 mg/kg and miR-155 was found to be significantly increased in heart challenged with LPS. Pharmacological inhibition of miR-155 using antagomiR improved cardiac function and suppressed cardiac apoptosis induced by LPS in mice as determined by echocardiography, terminal deoxynucleotidyl transferase nick-end labeling (TUNEL assay, and Western blot for Bax and Bcl-2, while overexpression of miR-155 using agomiR had inverse effects. Pea15a was identified as a target gene of miR-155, mediating its effects in controlling apoptosis of cardiomyocytes as evidenced by luciferase reporter assays, quantitative real time-polymerase chain reaction, Western blot, and TUNEL staining. Noteworthy, miR-155 was also found to be upregulated in the plasma of patients with septic cardiac dysfunction compared to sepsis patients without cardiac dysfunction, indicating a potential clinical relevance of miR-155. The receiver-operator characteristic curve indicated that plasma miR-155 might be a biomarker for sepsis patients developing cardiac dysfunction. Therefore, inhibition of miR-155 represents a novel therapy for septic myocardial dysfunction.

21 CFR 163.155 - Milk chocolate and vegetable fat coating.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Milk chocolate and vegetable fat coating. 163.155... § 163.155 Milk chocolate and vegetable fat coating. (a) Description. Milk chocolate and vegetable fat... label declaration of ingredients for milk chocolate in § 163.130 or skim milk chocolate in § 163.140...

Self-healing Li-Al layered double hydroxide conversion coating modified with aspartic acid for 6N01 Al alloy

Science.gov (United States)

Zhang, Caixia; Luo, Xiaohu; Pan, Xinyu; Liao, Liying; Wu, Xiaosong; Liu, Yali

2017-02-01

A self-healing Li-Al layered double hydroxide conversion coating (LCC) modified with aspartic acid (ALCC) was prepared on 6N01 Al alloy for corrosion protection. Scanning electron microscopy (SEM) showed that a compact thin film has been successfully formed on the alloy. X-ray diffraction (XRD) and FT-IR spectra proved that species of aspartic acid anions were successfully intercalated into LCC. Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and neutral salt spray (NSS) testing showed that the resultant ALCC could provide effective corrosion protection for the Al alloy. During immersion of the ALCC-coated alloy in 3.5% NaCl solution, new film was formed in the area of artificially introduced scratch, indicating its self-healing capability. XPS results demonstrated that Cl- anions exchange partial Asp anions according to the change content of element on conversion coating. From the above results, the possible mechanism via exchange/self-assembly was proposed to illustrate the phenomenon of self-healing.

Swelling in neutron-irradiated titanium alloys

International Nuclear Information System (INIS)

Peterson, D.T.

1982-04-01

Immersion density measurements have been performed on a series of titanium alloys irradiated in EBR-II to a fluence of 5 x 10 22 n/cm 2 (E > 0.1 MeV) at 450 and 550 0 C. The materials irradiated were the near-alpha alloys Ti-6242S and Ti-5621S, the alpha-beta alloy Ti-64, and the beta alloy Ti-38644. Swelling was observed in all alloys with the greater swelling being observed at 550 0 C. Microstructural examination revealed the presence of voids in all alloys. Ti-38644 was found to be the most radiation resistant. Ti-6242S and Ti-5621S also displayed good radiation resistance, whereas considerable swelling and precipitation were observed in Ti-64 at 550 0 C

PtNi Alloy Cocatalyst Modification of Eosin Y-Sensitized g-C3N4/GO Hybrid for Efficient Visible-Light Photocatalytic Hydrogen Evolution

Science.gov (United States)

Wang, Peng; Zong, Lanlan; Guan, Zhongjie; Li, Qiuye; Yang, Jianjun

2018-02-01

An economic and effective Pt-based alloy cocatalyst has attracted considerable attention due to their excellent catalytic activity and reducing Pt usage. In this study, PtNi alloy cocatalyst was successfully decorated on the g-C3N4/GO hybrid photocatalyst via a facile chemical reduction method. The Eosin Y-sensitized g-C3N4/PtNi/GO-0.5% composite photocatalyst yields about 1.54 and 1178 times higher hydrogen evolution rate than the Eosin Y-sensitized g-C3N4/Pt/GO-0.5% and g-C3N4/Ni/GO-0.5% samples, respectively. Mechanism of enhanced performance for the g-C3N4/PtNi/GO composite was also investigated by different characterization, such as photoluminescence, transient photocurrent response, and TEM. These results indicated that enhanced charge separation efficiency and more reactive sites are responsible for the improved hydrogen evolution performance due to the positive synergetic effect between Pt and Ni. This study suggests that PtNi alloy can be used as an economic and effective cocatalyst for hydrogen evolution reaction. [Figure not available: see fulltext.

Moessbauer and X-ray Study of Fe1-xAlx, 0.2≤x≤0.5, Samples Produced by Mechanical Alloying

International Nuclear Information System (INIS)

Oyola Lozano, D.; MartInez, Y. Rojas; Bustos, H.; Perez Alcazar, G. A.

2004-01-01

In this work we report the magnetic and structural properties obtained by Moessbauer spectroscopy and X-ray diffraction, of the Fe 1-x Al x , 0.2≤x≤0.5, alloys produced by mechanical alloying. Alloys with x=0.2, 0.3, 0.4 and 0.5, were for milled 12, 24, 36, and 48 hours. All the obtained alloys are in the bcc phase. The obtained Moessbauer spectra are characteristic of disordered ferromagnetic system. The lattice parameter remains nearly constant (∼2.91 A) for all the milling times and compositions. The mean grain sizes in the (110) and (211) direction are nearly constants with the milling time but vary from 15.5 to 11 nm and from 10.5 to 8.5 nm when Al content grow between x=0.2 to x=0.4, respectively. The difference between the mean grain sizes in these two directions shows that the grains are of prolate spheroid form.

Single-phase high-entropy alloys. An overview

Energy Technology Data Exchange (ETDEWEB)

Kozak, Roksolana; Steurer, Walter [ETH Zurich (Switzerland). Lab. of Crystallography; Sologubenko, Alla [ETH Zurich (Switzerland). Lab. of Nanotechnology

2015-02-01

The term 'high-entropy alloys (HEAs)' first appeared about 10 years ago defining alloys composed of n=5-13 principal elements with concentrations of approximately 100/n at.% each. Since then many equiatomic (or near equiatomic) single- and multi-phase multicomponent alloys were developed, which are reported for a combination of tunable properties: high hardness, strength and ductility, oxidation and wear resistance, magnetism, etc. In our paper, we focus on probably single-phase HEAs (solid solutions) out of all HEAs studied so far, discuss ways of their prediction, mechanical properties. In contrast to classical multielement/multiphase alloys, only single-phase multielement alloys (solid solutions) represent the basic concept underlying HEAs as mixing-entropy stabilized homogenous materials. The literature overview is complemented by own studies demonstrating that the alloys CrFeCoNi, CrFeCoNiAl{sub 0.3} and PdFeCoNi homogenized at 1300 and 1100 C, respectively, for 1 week are not single-phase HEAs, but a coherent mixture of two solid solutions.

Environmental fatigue in aluminum-lithium alloys

Science.gov (United States)

Piascik, Robert S.

1992-01-01

Aluminum-lithium alloys exhibit similar environmental fatigue crack growth characteristics compared to conventional 2000 series alloys and are more resistant to environmental fatigue compared to 7000 series alloys. The superior fatigue crack growth behavior of Al-Li alloys 2090, 2091, 8090, and 8091 is due to crack closure caused by tortuous crack path morphology and crack surface corrosion products. At high R and reduced closure, chemical environment effects are pronounced resulting in accelerated near threshold da/dN. The beneficial effects of crack closure are minimized for small cracks resulting in rapid growth rates. Limited data suggest that the 'chemically small crack' effect, observed in other alloy system, is not pronounced in Al-Li alloys. Modeling of environmental fatigue in Al-Li-Cu alloys related accelerated fatigue crack growth in moist air and salt water to hydrogen embrittlement.

Anti-Invar properties and magnetic order in fcc Fe-Ni-C alloy

International Nuclear Information System (INIS)

Nadutov, V.M.; Kosintsev, S.G.; Svystunov, Ye.O.; Garamus, V.M.; Willumeit, R.; Eckerlebe, H.; Ericsson, T.; Annersten, H.

2011-01-01

Anti-Invar effect was revealed in the fcc Fe-25.3%Ni-0.73%C (wt%) alloy, which demonstrates high values of thermal expansion coefficient (TEC) (15-21)x10 -6 K -1 accompanied by almost temperature-insensitive behavior in temperature range of 122-525 K. Alloying with carbon considerably expanded the low temperature range of anti-Invar behavior in fcc Fe-Ni-based alloy. The Curie temperature of the alloy T C =195 K was determined on measurements of temperature dependences of magnetic susceptibility and saturation magnetization. The Moessbauer and small-angle neutron scattering (SANS) experiments on the fcc Fe-25.3%Ni-(0.73-0.78)%C alloys with the varying temperatures below and above the Curie point and in external magnetic field of 1.5-5 T were conducted. Low value of the Debye temperature Θ D =180 K was estimated using the temperature dependence of the integral intensity of Moessbauer spectra for specified temperature range. The inequality B eff =(0.7-0.9)B ext was obtained in external field Moessbauer measurement that points to antiferromagnetically coupled Fe atoms, which have a tendency to align their spins perpendicular to B ext . Nano length scale magnetic inhomogeneities nearby and far above T C were revealed, which assumed that it is caused by mixed antiferromagnetically and ferromagnetically coupled Fe atom spins. The anti-Invar behavior of Fe-Ni-C alloy is explained in terms of evolution of magnetic order with changing temperature resulting from thermally varied interspin interaction and decreasing stiffness of interatomic bond. - Highlights: → Anti-Invar effect was revealed in the fcc Fe-25.3%Ni-0.73%C (wt%) alloy. → Carbon expanded the temperature range of anti-Invar behavior in Fe-Ni-based alloy. → Moessbauer data point to mixed interspin interaction and low the Dedye temperature. → The SANS experiments reveal nano length scale magnetic inhomogeneities ≤6 nm. → Anti-Invar behavior of Fe-Ni-C alloy explained by thermally varied magnetic order.

PHASE CONSTITUENTS AND MICROSTRUCTURE OF Ti3Al/Fe3Al + TiN/TiB2 COMPOSITE COATING ON TITANIUM ALLOY

OpenAIRE

JIANING LI; CHUANZHONG CHEN; CUIFANG ZHANG

2011-01-01

Laser cladding of the Fe3Al + B4C/TiN + Al2O3 pre-placed powders on the Ti-6Al-4V alloy can form the Ti3Al/Fe3Al + TiN/TiB2 composite coating, which improved the wear resistance of the Ti-6Al-4V alloy surface. In this study, the Ti3Al/Fe3Al + TiN/TiB2 composite coating has been researched by means of X-ray diffraction and scanning electron microscope. It was found that during the laser cladding process, Al2O3 can react with TiB2, leading to the formations of Ti3Al and B. This principle can be...

Phosphorylated SAP155, the spliceosomal component, is localized to chromatin in postnatal mouse testes

Energy Technology Data Exchange (ETDEWEB)

Eto, Ko, E-mail: etoko@gpo.kumamoto-u.ac.jp [Department of Biological Sciences, Graduate School of Science and Technology, Kumamoto University, Kumamoto 860-8555 (Japan); Sonoda, Yoshiyuki [Department of Biological Sciences, Graduate School of Science and Technology, Kumamoto University, Kumamoto 860-8555 (Japan); Jin, Yuji [School of Basic Medicine, Jilin Medical College, Jilin 132013 (China); Abe, Shin-ichi [Department of Biological Sciences, Graduate School of Science and Technology, Kumamoto University, Kumamoto 860-8555 (Japan)

2010-03-19

SAP155 is an essential component of the spliceosome and its phosphorylation is required for splicing catalysis, but little is known concerning its expression and regulation during spermatogenesis in postnatal mouse testes. We report that SAP155 is ubiquitously expressed in nuclei of germ and Sertoli cells within the seminiferous tubules of 6- and 35-day postpartum (dpp) testes. Analyses by fractionation of testes revealed that (1) phosphorylated SAP155 was found in the fraction containing nuclear structures at 6 dpp in amounts much larger than that at other ages; (2) non-phosphorylated SAP155 was detected in the fraction containing nucleoplasm; and (3) phosphorylated SAP155 was preferentially associated with chromatin. Our findings suggest that the active spliceosome, containing phosphorylated SAP155, performs pre-mRNA splicing on chromatin concomitant with transcription during testicular development.

Survivin selective inhibitor YM155 induce apoptosis in SK-NEP-1 Wilms tumor cells

International Nuclear Information System (INIS)

Tao, Yan-Fang; Wu, Dong; Wang, Na; Feng, Xing; Li, Yan-Hong; Ni, Jian; Wang, Jian; Pan, Jian; Lu, Jun; Du, Xiao-Juan; Sun, Li-Chao; Zhao, Xuan; Peng, Liang; Cao, Lan; Xiao, Pei-Fang; Pang, Li

2012-01-01

Survivin, a member of the family of inhibitor of apoptosis proteins, functions as a key regulator of mitosis and programmed cell death. YM155, a novel molecular targeted agent, suppresses survivin, which is overexpressed in many tumor types. The aim of this study was to determine the antitumor activity of YM155 in SK-NEP-1 cells. SK-NEP-1 cell growth in vitro and in vivo was assessed by MTT and nude mice experiments. Annexin V/propidium iodide staining followed by flow cytometric analysis was used to detect apoptosis in cell culture. Then gene expression profile of tumor cells treated with YM155 was analyzed with real-time PCR arrays. We then analyzed the expression data with MEV (Multi Experiment View) cluster software. Datasets representing genes with altered expression profile derived from cluster analyses were imported into the Ingenuity Pathway Analysis tool. YM155 treatment resulted in inhibition of cell proliferation of SK-NEP-1cells in a dose-dependent manner. Annexin V assay, cell cycle, and activation of caspase-3 demonstrates that YM155 induced apoptosis in SK-NEP-1 cells. YM155 significantly inhibited growth of SK-NEP-1 xenografts (YM155 5 mg/kg: 1.45 ± 0.77 cm 3 ; YM155 10 mg/kg: 0.95 ± 0.55 cm 3 ) compared to DMSO group (DMSO: 3.70 ± 2.4 cm 3 ) or PBS group cells (PBS: 3.78 ± 2.20 cm 3 , ANOVA P < 0.01). YM155 treatment decreased weight of tumors (YM155 5 mg/kg: 1.05 ± 0.24 g; YM155 10 mg/kg: 0.72 ± 0.17 g) compared to DMSO group (DMSO: 2.06 ± 0.38 g) or PBS group cells (PBS: 2.36 ± 0.43 g, ANOVA P < 0.01). Real-time PCR array analysis showed between Test group and control group there are 32 genes significantly up-regulated and 54 genes were significantly down-regulated after YM155 treatment. Ingenuity pathway analysis (IPA) showed cell death was the highest rated network with 65 focus molecules and the significance score of 44. The IPA analysis also groups the differentially expressed genes into biological mechanisms that are related to cell

Efficiency Drop in Green InGaN /GaN Light Emitting Diodes: The Role of Random Alloy Fluctuations

Science.gov (United States)

Auf der Maur, Matthias; Pecchia, Alessandro; Penazzi, Gabriele; Rodrigues, Walter; Di Carlo, Aldo

2016-01-01

White light emitting diodes (LEDs) based on III-nitride InGaN /GaN quantum wells currently offer the highest overall efficiency for solid state lighting applications. Although current phosphor-converted white LEDs have high electricity-to-light conversion efficiencies, it has been recently pointed out that the full potential of solid state lighting could be exploited only by color mixing approaches without employing phosphor-based wavelength conversion. Such an approach requires direct emitting LEDs of different colors, including, in particular, the green-yellow range of the visible spectrum. This range, however, suffers from a systematic drop in efficiency, known as the "green gap," whose physical origin has not been understood completely so far. In this work, we show by atomistic simulations that a consistent part of the green gap in c -plane InGaN /GaN -based light emitting diodes may be attributed to a decrease in the radiative recombination coefficient with increasing indium content due to random fluctuations of the indium concentration naturally present in any InGaN alloy.

Microstructure and corrosion behavior of electrodeposited nano-crystalline nickel coating on AZ91 Mg alloy

Energy Technology Data Exchange (ETDEWEB)

Zarebidaki, Arman, E-mail: arman.zare@iauyazd.ac.ir; Mahmoudikohani, Hassan, E-mail: hassanmahmoudi.k@gmail.com; Aboutalebi, Mohammad-Reza

2014-12-05

Highlights: • Activation, zincating, and Cu electrodeposition were used as pretreatment processes for electrodeposition of nickel coatings. • Nano-crystalline nickel coatings were successfully electrodeposited onto the AZ91 Mg alloys. • Effect of nickel electrodeposited coating on the corrosion resistance of AZ91 Mg alloy has been studied. - Abstract: In order to enhance the corrosion resistance, nickel coating was electrodeposited onto AZ91 Mg alloy. Activation, zincating, and Cu electrodeposition used as pretreatment processes for better adhesion and corrosion performance of the nickel over layer. The corrosion properties of the AZ91 Mg alloy, nickel electroplated AZ91 Mg alloy, and pure nickel was assessed via polarization and electrochemical impedance spectroscopy (EIS) methods in 3.5 wt% NaCl solution. Moreover, the structure of the coating was investigated by means of X-ray diffraction, whereas specimen’s morphology and elemental composition were analyzed using scanning electron microscope (SEM) equipped with energy dispersive spectrometer (EDS). Measurements revealed that the coating has a nano-crystalline structure with the grain size of 95 nm. Corrosion results showed superior corrosion resistance for the coated AZ91 Mg alloy as the corrosion current density decreased from 2.5 × 10{sup −4} A cm{sup −2}, for the uncoated sample, to 1.5 × 10{sup −5} A cm{sup −2}, for coated specimen and the corrosion potential increased from −1.55 V to −0.98 V (vs. Ag/AgCl) at the same condition.

Effect of Microstructure and Alloy Chemistry on Hydrogen Embrittlement of Precipitation-Hardened Ni-Based Alloys

Science.gov (United States)

Obasi, G. C.; Zhang, Z.; Sampath, D.; Morana, Roberto; Akid, R.; Preuss, M.

2018-04-01

The sensitivity to hydrogen embrittlement (HE) has been studied in respect of precipitation size distributions in two nickel-based superalloys: Alloy 718 (UNS N07718) and Alloy 945X (UNS N09946). Quantitative microstructure analysis was carried out by the combination of scanning and transmission electron microscopy and energy dispersive x-ray spectroscopy (EDS). While Alloy 718 is mainly strengthened by γ″, and therefore readily forms intergranular δ phase, Alloy 945X has been designed to avoid δ formation by reducing Nb levels providing high strength through a combination of γ' and γ″. Slow strain rate tensile tests were carried out for different microstructural conditions in air and after cathodic hydrogen (H) charging. HE sensitivity was determined based on loss of elongation due to the H uptake in comparison to elongation to failure in air. Results showed that both alloys exhibited an elevated sensitivity to HE. Fracture surfaces of the H precharged material showed quasi-cleavage and transgranular cracks in the H-affected region, while ductile failure was observed toward the center of the sample. The crack origins observed on the H precharged samples exhibited quasi-cleavage with slip traces at high magnification. The sensitivity is slightly reduced for Alloy 718, by coarsening γ″ and reducing the overall strength of the alloy. However, on further coarsening of γ″, which promotes continuous decoration of grain boundaries with δ phase, the embrittlement index rose again indicating a change of hydrogen embrittlement mechanism from hydrogen-enhanced local plasticity (HELP) to hydrogen-enhanced decohesion embrittlement (HEDE). In contrast, Alloy 945X displayed a strong correlation between strength, based on precipitation size and embrittlement index, due to the absence of any significant formation of δ phase for the investigated microstructures. For the given test parameters, Alloy 945X did not display any reduced sensitivity to HE compared with

PVR/CD155 Ala67Thr Mutation and Cleft Lip/Palate.

Science.gov (United States)

Vieira, Alexandre R; Letra, Ariadne; Silva, Renato M; Granjeiro, Jose M; Shimizu, Takehiko; Poletta, Fernando A; Mereb, Juan C; Castilla, Eduardo E; Orioli, Iêda M

2018-03-01

The 19q13 locus has been linked to cleft lip and palate by our group and independently by others. Here we fine mapped the region in an attempt to identify an etiological variant that can explain cleft lip and palate occurrence. A total of 2739 individuals born with cleft lip and palate, related to individuals born with cleft lip and palate, and unrelated were studied. We used linkage and association approaches to fine map the interval between D19S714 and D19S433 and genotypes were defined by the use of TaqMan chemistry. We confirmed our previous findings that markers in PVR/CD155 are associated with cleft lip and palate. We studied the mutation Ala67Thr further and calculated its penetrance. We also attempted to detect PVR/CD155 expression in human whole saliva. Our results showed that markers in PVR/CD155 are associated with cleft lip and palate and the penetrance of the Ala67Thr is very low (between 1% and 5%). We could not detect PVR/CD155 expression in adult human whole saliva and PVR/CD155 possibly interacts with maternal infection to predispose children to cleft lip only.

In Situ Synthesis of Al-Based MMCs Reinforced with AlN by Mechanical Alloying under NH3 Gas

Directory of Open Access Journals (Sweden)

E. S. Caballero

2018-05-01

Full Text Available Aluminum matrix composites (AMCs reinforced by aluminum nitride were prepared by mechanical alloying followed by a simple press and sintering method. Milling began under vacuum and after a period of between 1 and 4 h, NH3 gas flow (1 cm3/s was incorporated until the total milling time of 5 h was reached. Results show that in addition to the strain hardening taking place during mechanical alloying, NH3 plays an additional role in powder hardening. Thereby, the properties of the sintered compacts are strongly influenced by the amount of N incorporated into the powders during milling and the subsequent formation of AlN during the consolidation process. The obtained AMC reaches tensile strengths as high as 459 MPa and hardness much higher than that of the as-received aluminum compact.

Fast LIBS Identification of Aluminum Alloys

Directory of Open Access Journals (Sweden)

Tawfik W.

2007-04-01

Full Text Available Laser-induced breakdown spectroscopy (LIBS has been applied to analysis aluminum alloy targets. The plasma is generated by focusing a 300 mJ pulsed Nd: YAG laser on the target in air at atmospheric pressure. Such plasma emission spectrum was collected using a one-meter length wide band fused-silica optical fiber connected to a portable Echelle spectrometer with intensified CCD camera. Spectroscopic analysis of plasma evolution of laser produced plasmas has been characterized in terms of their spectra, electron density and electron temperature assuming the LTE and optically thin plasma conditions. The LIBS spectrum was optimized for high S/N ratio especially for trace elements. The electron temperature and density were determined using the emission intensity and stark broadening, respectively, of selected aluminum spectral lines. The values of these parameters were found to change with the aluminum alloy matrix, i.e. they could be used as a fingerprint character to distinguish between different aluminum alloy matrices using only one major element (aluminum without needing to analysis the rest of elements in the matrix. Moreover, It was found that the values of T e and N e decrease with increasing the trace elements concentrations in the aluminum alloy samples. The obtained results indicate that it is possible to improve the exploitation of LIBS in the remote on-line industrial monitoring application, by following up only the values of T e and N e for aluminum in aluminum alloys as a marker for the correct alloying using an optical fiber probe.

Survivin inhibitor YM155 suppresses gastric cancer xenograft growth in mice without affecting normal tissues.

Science.gov (United States)

Cheng, Xiao Jiao; Lin, Jia Cheng; Ding, Yan Fei; Zhu, Liming; Ye, Jing; Tu, Shui Ping

2016-02-09

Survivin overexpression is associated with poor prognosis of human gastric cancer, and is a target for gastric cancer therapy. YM155 is originally identified as a specific inhibitor of survivin. In this study, we investigated the antitumor effect of YM155 on human gastric cancer. Our results showed that YM155 treatment significantly inhibited cell proliferation, reduced colony formation and induced apoptosis of gastric cancer cells in a dose-dependent manner. Accordingly, YM155 treatment significantly decreased survivin expression without affecting XIAP expression and increased the cleavage of apoptosis-associated proteins caspase 3, 7, 8, 9. YM155 significantly inhibited sphere formation of gastric cancer cells, suppressed expansion and growth of the formed spheres (cancer stem cell-like cells, CSCs) and downregulated the protein levels of β-catenin, c-Myc, Cyclin D1 and CD44 in gastric cancer cells. YM155 infusion at 5 mg/kg/day for 7 days markedly inhibited growth of gastric cancer xenograft in a nude mouse model. Immunohistochemistry staining and Western Blot showed that YM155 treatment inhibited expression of survivin and CD44, induced apoptosis and reduced CD44+ CSCs in xenograft tumor tissues in vivo. No obvious pathological changes were observed in organs (e.g. heart, liver, lung and kidney) in YM155-treated mice. Our results demonstrated that YM155 inhibits cell proliferation, induces cell apoptosis, reduces cancer stem cell expansion, and inhibits xenograft tumor growth in gastric cancer cells. Our results elucidate a new mechanism by which YM155 inhibits gastric cancer growth by inhibition of CSCs. YM155 may be a promising agent for gastric cancer treatment.

42 CFR 440.155 - Nursing facility services, other than in institutions for mental diseases.

Science.gov (United States)

2010-10-01

... institutions for mental diseases. 440.155 Section 440.155 Public Health CENTERS FOR MEDICARE & MEDICAID... PROVISIONS Definitions § 440.155 Nursing facility services, other than in institutions for mental diseases. (a) “Nursing facility services, other than in an institution for mental diseases” means services...

20 CFR 402.155 - Fees to be charged-categories of requests.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Fees to be charged-categories of requests. 402.155 Section 402.155 Employees' Benefits SOCIAL SECURITY ADMINISTRATION AVAILABILITY OF INFORMATION... institutions and news media. If you are an educational institution or a non-commercial scientific institution...

Electrical Resistance Alloys and Low-Expansion Alloys

DEFF Research Database (Denmark)

Kjer, Torben

1996-01-01

The article gives an overview of electrical resistance alloys and alloys with low thermal expansion. The electrical resistance alloys comprise resistance alloys, heating alloys and thermostat alloys. The low expansion alloys comprise alloys with very low expansion coefficients, alloys with very low...... thermoelastic coefficients and age hardenable low expansion alloys....

Indirect improvement of high temperature mechanical properties of a Mg-based alloy Elektron21 by addition of AlN nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Daudin, R. [Univ. Grenoble Alpes, CNRS, SIMaP, F-38000 Grenoble (France); Terzi, S. [European Space Agency, ESTEC, TEC-TS, EPN Campus, CS20156, 38042 Grenoble Cedex 9 (France); Mallmann, C. [Univ. Grenoble Alpes, CNRS, SIMaP, F-38000 Grenoble (France); Martín, R. Sánchez [IMDEA Materials Institute, Tecnogetafe C/ Eric Kandel, 2, 28906 Getafe, Madrid (Spain); Lhuissier, P. [Univ. Grenoble Alpes, CNRS, SIMaP, F-38000 Grenoble (France); Boller, E.; Pacureanu, A. [European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble (France); Katsarou, L.; Dieringa, H. [Helmholtz-Zentrum Geesthacht, Magnesium Innovation Centre – MagIC, Max-Planck-Str. 1, 21502 Geesthacht (Germany); Salvo, L. [Univ. Grenoble Alpes, CNRS, SIMaP, F-38000 Grenoble (France)

2017-03-14

Magnesium being the lightest metal on earth used as a structural material, the design of the chemistry and the microstructures of Mg-based alloys has been developed over the years to always further ameliorate their mechanical properties. A supplementary option consists in adding ceramic nanoparticles to such alloys to design Mg-based metal matrix nanocomposites (MMNCs) displaying improvement of both strength and ductility. In practice however, careful attention is required to understand the fundamental mechanisms at the heart of the enhancement of these properties as they still remain quite uncertain and subjected to misleading interpretations. Here, high temperature (350 °C) strain rate jump tests in compression reveal an enhancement of 20–60% of the mechanical properties when AlN nano-particles are added to the Elektron21 alloy (Mg-2.8Nd-1.2Gd-0.4Zr-0.3Zn, in wt%). At the same time, nano-indentation investigations suppose that forest or Orowan strengthening, due to particles-dislocations interactions, is unlikely to occur. Instead, using complementary microstructural characterization techniques (scanning electron macroscopy, energy dispersive spectroscopy as well as micro- and nano-tomography), we show that AlN nano-particles physically and chemically interact with the alloy and modify the overall microstructure, in particular the intermetallic phase, at the origin of the improvement of the mechanical properties.

Spectroelectrochemical detection of microRNA-155 based on functional RNA immobilization onto ITO/GNP nanopattern.

Science.gov (United States)

Mohammadniaei, Mohsen; Yoon, Jinho; Lee, Taek; Choi, Jeong-Woo

2018-05-20

We fabricated a microRNA biosensor using the combination of surface enhanced Raman spectroscopy (SERS) and electrochemical (EC) techniques. For the first time, the weaknesses of each techniques for microRNA detection was compensated by the other ones to give rise to the specific and wide-range detection of miR-155. A single stranded 3' methylene blue (MB) and 5' thiol-modified RNA (MB-ssRNA-SH) was designed to detect the target miR-155 and immobilized onto the gold nanoparticle-modified ITO (ITO/GNP). Upon the invasion of target strand, the double-stranded RNA transformed rapidly to an upright structure resulting in a notable decrease in SERS and redox signals of the MB. For the first time, by combination of SERS and EC techniques in a single platform we extended the dynamic range of both techniques from 10 pM to 450 nM (SERS: 10 pM-5 nM and EC: 5 nM-450 nM). As well, the SERS technique improved the detection limit of the EC method from 100 pM to 100 fM, while the EC method covered single-mismatch detection which was the SERS deficiency. The fabricated single-step biosensor possessing a good capability of miRNA detection in human serum, could be employed throughout the broad ranges of biomedical and bioelectronics applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Temperature-dependent elastic properties of Ti{sub 1−x}Al{sub x}N alloys

Energy Technology Data Exchange (ETDEWEB)

Shulumba, Nina [Department of Physics, Chemistry, and Biology (IFM), Linköping University, SE-581 83 Linköping (Sweden); Functional Materials, Saarland University, D-66123 Saarbrücken (Germany); Hellman, Olle [Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125 (United States); Department of Physics, Chemistry, and Biology (IFM), Linköping University, SE-581 83 Linköping (Sweden); Rogström, Lina; Raza, Zamaan; Tasnádi, Ferenc; Odén, Magnus [Department of Physics, Chemistry, and Biology (IFM), Linköping University, SE-581 83 Linköping (Sweden); Abrikosov, Igor A. [Department of Physics, Chemistry, and Biology (IFM), Linköping University, SE-581 83 Linköping (Sweden); Materials Modeling and Development Laboratory, NUST “MISIS,” 119049 Moscow (Russian Federation); LACOMAS Laboratory, Tomsk State University, 634050 Tomsk (Russian Federation)

2015-12-07

Ti{sub 1−x}Al{sub x}N is a technologically important alloy that undergoes a process of high temperature age-hardening that is strongly influenced by its elastic properties. We have performed first principles calculations of the elastic constants and anisotropy using the symmetry imposed force constant temperature dependent effective potential method, which include lattice vibrations and therefore the effects of temperature, including thermal expansion and intrinsic anharmonicity. These are compared with in situ high temperature x-ray diffraction measurements of the lattice parameter. We show that anharmonic effects are crucial to the recovery of finite temperature elasticity. The effects of thermal expansion and intrinsic anharmonicity on the elastic constants are of the same order, and cannot be considered separately. Furthermore, the effect of thermal expansion on elastic constants is such that the volume change induced by zero point motion has a significant effect. For TiAlN, the elastic constants soften non-uniformly with temperature: C{sub 11} decreases substantially when the temperature increases for all compositions, resulting in an increased anisotropy. These findings suggest that an increased Al content and annealing at higher temperatures will result in a harder alloy.

A phase 2, multicenter, open-label study of sepantronium bromide (YM155) plus docetaxel in patients with stage III (unresectable) or stage IV melanoma

International Nuclear Information System (INIS)

Kudchadkar, Ragini; Ernst, Scott; Chmielowski, Bartosz; Redman, Bruce G; Steinberg, Joyce; Keating, Anne; Jie, Fei; Chen, Caroline; Gonzalez, Rene; Weber, Jeffrey

2015-01-01

Survivin is a microtubule-associated protein believed to be involved in preserving cell viability and regulating tumor cell mitosis, and it is overexpressed in many primary tumor types, including melanoma. YM155 is a first-in-class survivin suppressant. The purpose of this Phase 2 study was to evaluate the 6-month progression-free survival (PFS) rate in patients with unresectable Stage III or IV melanoma receiving a combination of YM155 plus docetaxel. The study had two parts: Part 1 established the dose of docetaxel that was tolerable in combination with YM155, and Part 2 evaluated the tolerable docetaxel dose (75 mg/m 2 ) in combination with YM155 (5 mg/m 2 per day continuous infusion over 168 h every 3 weeks). The primary endpoint was 6-month PFS rate. Secondary endpoints were objective response rate (ORR), 1-year overall survival (OS) rate, time from first response to progression, clinical benefit rate (CBR), and safety. Sixty-four patients with metastatic melanoma were treated with docetaxel and YM155. Eight patients received an initial docetaxel dose of 100 mg/m 2 and 56 patients received 75 mg/m 2 of docetaxel. Six-month PFS rate per Independent Review Committee (IRC) was 34.8% (n = 64; 95% CI, 21.3–48.6%), and per Investigator was 31.3% (n = 64; 95% CI, 19.5–43.9%). The best ORR (complete response [CR] + partial response [PR]) per IRC was 12.5% (8/64). The stable disease (SD) rate was 51.6% (33/64), leading to a CBR (CR + PR + SD) of 64.1% (41/64). Estimated probability of 1-year survival was 56.3%. YM155 is a novel agent showing modest activity when combined with docetaxel for treating patients with melanoma. YM155 was generally well tolerated, but the predetermined primary efficacy endpoint (i.e., 6-month PFS rate ≥20%) was not achieved

Irradiation effects in magnesium and aluminium alloys

International Nuclear Information System (INIS)

Sturcken, E.F.

1979-01-01

Effects of neutron irradiation on microstructure, mechanical properties and swelling of several magnesium and aluminium alloys were studied. The neutron fluences of 2-3 X 10 22 n/cm 2 , >0.2 MeV produced displacement doses of 20 to 45 displacements per atom (dpa). Ductility of the magnesium alloys was severely reduced by irradiation induced recrystallization and precipitation of various forms. Precipitation of transmuted silicon occurred in the aluminium alloys. However, the effect on ductility was much less than for the magnesium alloys. The magnesium and aluminium alloys had excellent resistance to swelling: The best magnesium alloy was Mg/3.0 wt% Al/0.19 wt% Ca; its density decreased by only 0.13%. The best aluminium alloy was 6063, with a density decrease of 0.22%. (Auth.)

Effect of nitrogen alloying on the microstructure and abrasive wear of stainless steels

International Nuclear Information System (INIS)

Hawk, J.A.; Simmons, J.W.; Rawers, J.C.

1994-01-01

Alloying stainless steels with nitrogen has distinct advantages. Nitrogen is a strong austenite stabilizer and a potent solid-solution strengthener, and nitrogen has greater solubility than carbon iron. This study investigates the relationship among nitrogen concentration, precipitate microstructure, and abrasive wear using two high-nitrogen stainless steel alloys: Fe-19Cr-5Mn-5Ni-3Mo (SS1) and Fe-16Cr-7Mn-5Ni(SS2). Alloy SS1 contained 0.7 wt% N and was solution annealed at 1,150 C, thereby dissolving the nitrogen interstitially in the austenite. Subsequent aging, or cold work and aging, at 900 C led to the grain-boundary, cellular, and transgranular precipitation of Cr 2 N. Alloy SS2 was remelted in a high-pressure (200 MPa) N 2 atmosphere, leading to a spatial gradient of nitrogen in the alloy in the form of interstitial nitrogen and Cr 2 N and CrN precipitates. Nitrogen contents varied from a low of approximately 0.7 wt% at the bottom of the billet to a high of 3.6 wt% at the top. Nitrogen in excess of approximately 0.7 wt% formed increasingly coarser and more numerous Cr 2 N and CrN precipitates. The precipitate morphology created in alloy SS1 due to aging, or cold work and aging, had little effect on the abrasive wear of the alloy. However, a decrease in the abrasive wear rate in alloy SS2 was observed to correspond to the increase in number and size of the Cr 2 N and CrN precipitates

Self-assembled GaN nano-column grown on Si(111) substrate using Au+Ga alloy seeding method by metalorganic chemical vapor deposition

International Nuclear Information System (INIS)

Shim, Byung-Young; Ko, Eun-A; Song, Jae-Chul; Kang, Dong-Hun; Kim, Dong-Wook; Lee, In-Hwan; Kannappan, Santhakumar; Lee, Cheul-Ro

2007-01-01

Single-crystal GaN nano-column arrays were grown on Au-coated silicon (111) substrate by Au-Ga alloy seeding method using metalorganic chemical vapor deposition (MOCVD). The nano-column arrays were studied as a function of growth parameters and Au thin film thickness. The diameter and length of the as-grown nano-column vary from 100 to 500 nm and 4 to 6 μm, respectively. The surface morphology and optical properties of the nano-columns were investigated using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), cathodoluminescence (CL) and photoluminescence (PL). The Au+Ga alloy droplets were found to be uniformly distributed on silicon surface. Further, SEM image reveals a vertical growth and cylindrical in shape GaN nano-column. The chemical composition of the nano-column, which composed of gallium and nitrogen ions, was estimated by EDX. CL reveals a strong band edge emission from the GaN nano-column. PL spectra show a peak at 365.7 nm with a full-width half maximum (FWHM) of 65 meV which indicates good optical quality GaN nano-column with low dislocation density. Our results suggest that single crystal GaN nano-column can be grown on Au+Ga alloy on silicon substrate with a low dislocation density for better device performances. (author)

Moessbauer and X-ray Study of Fe{sub 1-x}Al{sub x}, 0.2{<=}x{<=}0.5, Samples Produced by Mechanical Alloying

Energy Technology Data Exchange (ETDEWEB)

Oyola Lozano, D., E-mail: doyola@ut.edu.co; MartInez, Y. Rojas; Bustos, H.; Perez Alcazar, G. A. [Universidad del Tolima, Departamento de Fisica (Colombia)

2004-12-15

In this work we report the magnetic and structural properties obtained by Moessbauer spectroscopy and X-ray diffraction, of the Fe{sub 1-x}Al{sub x}, 0.2{<=}x{<=}0.5, alloys produced by mechanical alloying. Alloys with x=0.2, 0.3, 0.4 and 0.5, were for milled 12, 24, 36, and 48 hours. All the obtained alloys are in the bcc phase. The obtained Moessbauer spectra are characteristic of disordered ferromagnetic system. The lattice parameter remains nearly constant ({approx}2.91 A) for all the milling times and compositions. The mean grain sizes in the (110) and (211) direction are nearly constants with the milling time but vary from 15.5 to 11 nm and from 10.5 to 8.5 nm when Al content grow between x=0.2 to x=0.4, respectively. The difference between the mean grain sizes in these two directions shows that the grains are of prolate spheroid form.

WC-3015 alloy (high-temperature alloy)

International Nuclear Information System (INIS)

Anon.

1974-01-01

WC-3015 Nb alloy containing 28 to 30 Hf, 1 to 2 Zr, 13 to 16 W, 0 to 4 Ta, 0 to 5 Ti, 0.07 to 0.33 C, less than or equal to 0.02 N, less than or equal to 0.03 O, less than or equal to 0.001 H was developed for use at high temperature in oxidizing environments. Its composition can be tailored to meet specific requirements. When WC-3015 is exposed to O at elevated temperature, Hf and Nb oxidized preferentially and HfO 2 dissolves in Nb 2 O 5 to form 6HfO-Nb 2 O 5 . This complex oxide has a tight cubic lattice which resists the diffusion of O into the substrate. During 24-h exposure to air at 2400 0 F, the alloy oxidizes to a depth of approximately 0.035 in. with a surface recession of 0 to 0.004 in. Oxidation resistance of WC-3015 welds and base material can be further enhanced greatly by applying silicide coatings. WC-3015 alloy can be machined by conventional and electrical-discharge methods. It can be hot worked readily by extrusion, forging or rolling. Cold working can be used at room or elevated temperature. It can be welded by the electron-beam or Tig processes. Physical constants, typical mechanical properties at 75 to 2400 0 F, and effects of composition and heat treatment on tensile and stress-rupture properties of the alloy are tabulated

Composition of the spheroidal objects in KhN77TYuR-VD alloy

International Nuclear Information System (INIS)

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

1986-01-01

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

Oxide dispersion-strengthened ferritic alloys

International Nuclear Information System (INIS)

Asbroeck, P. van.

1976-10-01

The publication gives the available data on the DTO2 dispersion-strengthened ferritic alloy developed at C.E.N./S.C.K. Mol, Belgium. DTO2 is a Fe-Cr-Mo ferritic alloy, strengthened by addition of titanium oxide and of titanium leading to the formation of Chi phase. It was developed for use as canning material for fast breeder reactors. (author)

Fast LIBS Identification of Aluminum Alloys

Directory of Open Access Journals (Sweden)

Tawfik W.

2007-04-01

Full Text Available Laser-induced breakdown spectroscopy (LIBS has been applied to analysis aluminum alloy targets. The plasma is generated by focusing a 300 mJ pulsed Nd: YAG laser on the target in air at atmospheric pressure. Such plasma emission spectrum was collected using a one-meter length wide band fused-silica optical fiber connected to a portable Echelle spectrometer with intensified CCD camera. Spectroscopic analysis of plasma evolution of laser produced plasmas has been characterized in terms of their spectra, electron density and electron temperature assuming the LTE and optically thin plasma conditions. The LIBS spectrum was optimized for high S/N ratio especially for trace elements. The electron temperature and density were determined using the emission intensity and stark broadening, respectively, of selected aluminum spectral lines. The values of these parameters were found to change with the aluminum alloy matrix, i.e. they could be used as a fingerprint character to distinguish between different aluminum alloy matrices using only one major element (aluminum without needing to analysis the rest of elements in the matrix. Moreover, It was found that the values of T(e and N(e decrease with increasing the trace elements concentrations in the aluminum alloy samples. The obtained results indicate that it is possible to improve the exploitation of LIBS in the remote on-line industrial monitoring application, by following up only the values of T(e and N(e for the aluminum in aluminum alloys using an optical fiber probe.

Inhibition of miR-155, a therapeutic target for breast cancer, prevented in cancer stem cell formation.

Science.gov (United States)

Zuo, Jiangcheng; Yu, Yalan; Zhu, Man; Jing, Wei; Yu, Mingxia; Chai, Hongyan; Liang, Chunzi; Tu, Jiancheng

2018-02-06

Breast cancer is a common cancer in women of worldwide. Cancer cells with stem-like properties played important roles in breast cancer, such as relapse, metastasis and treatment resistance. Micro-RNA-155 (miR-155) is a well-known oncogenic miRNA overexpressed in many human cancers. The expression levels of miR-155 in 38 pairs of cancer tissues and adjacent normal tissues from breast cancer patients were detected using quantitative real-time PCR. The invasive cell line MDA-MB-231 was used to quantify the expression of miR-155 by tumor-sphere forming experiment. Soft agar colony formation assay and tumor xenografts was used to explore whether the inhibition of miR-155 could reduce proliferation of cancer cells in vivo and vitro. In the study, we found miR-155 was upregulated in BC. Soft agar colony formation assay and tumor xenografts showed inhibition of miR-155 could significantly reduce proliferation of cancer cells in vivo and vitro, which confirmed that miR-155 is an effective therapeutic target of breast cancer. Sphere-forming experiment showed that overexpression of miR-155 significantly correlated with stem-like properties. Expressions of ABCG2, CD44 and CD90 were repressed by inhibition of miR-155, but CD24 was promoted. Interestingly, inhibition of miR-155 rendered MDA-MB-231 cells more sensitive to Doxorubicinol, which resulted in an increase of inhibition rate from 20.23% to 68.72%. Expression of miR-155 not only was a therapeutic target but also was associated with cancer stem cell formation and Doxorubicinol sensitivity. Our results underscore the importance of miR-155 as a therapeutic target and combination of Doxorubicinol and miR-155-silencing would be a potential way to cure breast cancer.

Effects of Sm addition on microstructure and mechanical properties of a Mg-10Y alloy

Directory of Open Access Journals (Sweden)

Li Quanan

2014-01-01

Full Text Available To further increase the mechanical properties, 0.5wt.% Sm was introduced to a Mg-10Y alloy in this study. The effects of Sm addition on the microstructures and mechanical properties of the Mg-10Y alloy, especially the aged Mg-10Y alloy, were investigated. The microstructure observation and tensile tests were performed by using an optical microscopy, a scanning electron microscopy and a universal material testing machine, respectively. The phase analysis was performed using X-ray diffractometer. The results show that the 0.5wt.% Sm addition can not only promote the formation of fine and dispersed Mg24Y5 phases, but also improve their morphology and distribution; it also increases the thermal stability of Mg24Y5 phases. Sm addition is seen to increase the ultimate tensile strength of Mg-10Y alloy at elevated temperatures (200, 250, 300 and 350 ℃, while decrease the elongation. But the elongation is still up to 7.5% even at 350 ℃. In the range of 250 ℃ to 300℃, the ultimate tensile strength of the alloy reaches its maximum (with a range average of 235 MPa and is not sensitive to the temperature change, which is very useful to the application of heat-resistant magnesium alloys. Even at 350 ℃, the ultimate tensile strength of Mg-10Y-0.5Sm is still up to 155 MPa. Considering both of the ultimate tensile strength and elongation, the maximum application temperature of the Mg-10Y-0.5Sm alloy can be up to 300 ℃. The strengthening mechanisms of Mg-10Y-0.5Sm alloy are mainly attributed to dispersion strengthening of Mg24Y5 phase particles with a certain solubility of Sm and grain refinement strengthening of α-Mg matrix.

In vitro bio-functional performances of the novel superelastic beta-type Ti-23Nb-0.7Ta-2Zr-0.5N alloy.

Science.gov (United States)

Ion, Raluca; Gordin, Doina-Margareta; Mitran, Valentina; Osiceanu, Petre; Dinescu, Sorina; Gloriant, Thierry; Cimpean, Anisoara

2014-02-01

The materials used for internal fracture fixations and joint replacements are mainly made of metals which still face problems ranging from higher rigidity than that of natural bone to leaching cytotoxic metallic ions. Beta (β)-type titanium alloys with low elastic modulus made from non-toxic and non-allergenic elements are desirable to reduce stress shielding effect and enhance bone remodeling. In this work, a new β-type Ti-23Nb-0.7Ta-2Zr-0.5N alloy with a Young's modulus of approximately 50 GPa was designed and characterized. The behavior of MC3T3-E1 pre-osteoblasts on the new alloy, including adhesion, proliferation and differentiation, was evaluated by examining the cytoskeleton, focal adhesion formation, metabolic activity and extracellular matrix mineralization. Results indicated that the pre-osteoblast cells exhibited a similar degree of attachment and growth on Ti-23Nb-0.7Ta-2Zr-0.5N and Ti-6Al-4V. However, the novel alloy proved to be significantly more efficient in sustaining mineralized matrix deposition upon osteogenic induction of the cells than Ti-6Al-4V control. Further, the analysis of RAW 264.7 macrophages cytokine gene and protein expression indicated no significant inflammatory response. Collectively, these findings suggest that the Ti-23Nb-0.7Ta-2Zr-0.5N alloy, which has an increased mechanical biocompatibility with bone, allows a better osteogenic differentiation of osteoblast precursor cells than Ti-6Al-4V and holds great potential for future clinical prosthetic applications. Copyright © 2013 Elsevier B.V. All rights reserved.

[Changes of expression of miR-155 in colitis-associated colonic carcinogenesis].

Science.gov (United States)

Li, Weiwei; Han, Wenxiao; Zhao, Xinhua; Wang, Hongying

2014-04-01

To investigate the changes of miR-155 and its target genes in colitis-associated carcinogenesis. Colitis-associated colon cancer was induced by azoxymethane (AOM) and dextran sulfate sodium (DSS) in C57BL/6 mice. Mice of three different stages during the development of colon cancer were obtained, named AD1, AD2 and AD3, respectively. A control group of mice without any treatment and a DSS only group representing chronic inflammation without cancer were set up as well. Colon tissue was collected and expression of miR-155 in the colon tissues was measured by real-time fluorescent quantitative PCR. TargetScan and PicTar were used to predict potential target genes of miR-155, which were then preliminarily screened with our gene expression microarray database of AOM-DSS mouse model. Regular PCR was used to confirm the changes of the expression of these potential target genes in AOM-DSS mouse model. Colitis-associated colon cancer was effectively induced by azoxymethane and dextran sulfate sodium in C57BL/6 mice. Histological examination revealed that the evolution process was sequentially from normal, mild dysplasia, moderate dysplasia, and severe dysplasia to adenocarcinoma in the AOM-DSS mouse model. The level of miR-155 was gradually elevated with the formation of colitis-associated colon cancer. There was no significant difference between the levels of miR-155 expression in the DSS group (0.005 6 ± 0.003 7) and control group (0.012 0 ± 0.005 1) (P > 0.05), but the level of miR-155 in the AD3 group (0.054 4 ± 0.027 0) was significantly higher than that of the DSS group (0.005 6 ± 0.003 7)(P Bcorl1, Cacna1c, Rspo2 and Foxo3 were potential target genes of miR-155 in the AOM-DSS mouse model. Changes of Kcna1 and Cacna1c in the AOM-DSS mouse model were validated to be consistent with the changes obtained with the gene expression microarray. The up-regulation of miR-155 is related to colitis-associated carcinogenesis, but is irrelevant to chronic inflammation in the

Natural functional SNPs in miR-155 alter its expression level, blood cell counts and immune responses

Directory of Open Access Journals (Sweden)

Congcong Li

2016-08-01

Full Text Available miR-155 has been confirmed to be a key factor in immune responses in humans and other mammals. Therefore, investigation of variations in miR-155 could be useful for understanding the differences in immunity between individuals. In this study, four SNPs in miR-155 were identified in mice (Mus musculus and humans (Homo sapiens. In mice, the four SNPs were closely linked and formed two miR-155 haplotypes (A and B. Ten distinct types of blood parameters were associated with miR-155 expression under normal conditions. Additionally, 4 and 14 blood parameters were significantly different between these two genotypes under normal and lipopolysaccharide (LPS stimulation conditions, respectively. Moreover, the expression levels of miR-155, the inflammatory response to LPS stimulation and the lethal ratio following Salmonella typhimurium infection were significantly increased in mice harboring the AA genotype. Further, two SNPs, one in the loop region and the other near the 3' terminal of pre-miR-155, were confirmed to be responsible for the differential expression of miR-155 in mice. Interestingly, two additional SNPs, one in the loop region and the other in the middle of miR-155*, modulated the function of miR-155 in humans. Predictions of secondary RNA structure using RNAfold showed that these SNPs affected the structure of miR-155 in both mice and humans. Our results provide novel evidence of the natural functional SNPs of miR-155 in both mice and humans, which may affect the expression levels of mature miR-155 by modulating its secondary structure. The SNPs of human miR-155 may be considered as causal mutations for some immune-related diseases in the clinic. The two genotypes of mice could be used as natural models for studying the mechanisms of immune diseases caused by abnormal expression of miR-155 in humans.

Effect of diluted alloying elements on mechanical properties of iron

International Nuclear Information System (INIS)

Hassan, A.A.S.

1996-01-01

Iron and its alloys have extensive applications. The effect of solute additions on mechanical properties of iron was investigated to check the efficiency of solute atoms on strength and surface e life. Additions in the range of 0.1 wt.% and 0.3 wt.% of alloying elements of Cu,Ni and Si were used. Samples of grains size ranged from 6-40 m which have been prepared by annealing followed by furnace cooling. The recrystallization temperature increases with alloying addition (475 degree C for Fe-0.3 wt. % C alloy compared to 375 degree C for pure iron). Si and Cu additions inhibit grain growth of iron whereas Ni addition enhances it.Addition of Si or Ni to iron induced softening below room temperature whereas addition of Cu caused hardening. The work hardening parameters decreased due to alloying additions. The strength coefficient K was 290 M N/m2 for Fe-03 wt % Ni compared to 340 M N/m2 for pure iron. The work hardening exponent n is 0.12 for fe-0.3 wt. Cu alloy compared to 0.17 for pure iron. All the investigated alloys fulfilled the Hall-Petch relation at liquid Nitrogen and at room temperature. Alloying addition which caused softening addition which caused hardening increased the Half-Petch parameters. Ni addition favors ductility of iron whereas Cu addition reduces it. Alloying additions generally lead to brittle fracture and decrease the crack resistance of iron. 9 tabs., 55 figs., 103 refs

21 CFR 155.120 - Canned green beans and canned wax beans.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Canned green beans and canned wax beans. 155.120... Vegetables § 155.120 Canned green beans and canned wax beans. (a) Identity—(1) Definition. Canned green beans and canned wax beans are the foods prepared from succulent pods of fresh green bean or wax bean plants...

21 CFR 155.201 - Canned mushrooms.

Science.gov (United States)

2010-04-01

... percent of the water capacity of the container. (iii) Determine drained weight as specified in § 155.3(a..., packed with a suitable liquid medium which may include water; and may contain one or more safe and... to promote color retention. (4) Labeling requirements. (i) The name of the food is mushrooms. The...

Enrichment of gadolinium-157 and gadolinium-155 by laser method

International Nuclear Information System (INIS)

Xinjun, Su; Xiaowei, Zhang; Zhiquan, Li

2008-01-01

Laser isotope separation experiments of gadolinium by atomic vapor method have been performed. Gadolinium-157 and gadolinium-155 were selectively photoionized by means of three linearly polarized dye lasers, the excitation process of which is based on the polarization selection rules. Gramme-magnitude of enriched gadolinium was obtained and the total abundance of gadolinium-157 and gadolinium-155 was in excess of 80%, and the product rating exceeded 200 mg/h. (author)

MicroRNA-155 attenuates late sepsis-induced cardiac dysfunction through JNK and β-arrestin 2.

Science.gov (United States)

Zhou, Yu; Song, Yan; Shaikh, Zahir; Li, Hui; Zhang, Haiju; Caudle, Yi; Zheng, Shouhua; Yan, Hui; Hu, Dan; Stuart, Charles; Yin, Deling

2017-07-18

Cardiac dysfunction is correlated with detrimental prognosis of sepsis and contributes to a high risk of mortality. After an initial hyperinflammatory reaction, most patients enter a protracted state of immunosuppression (late sepsis) that alters both innate and adaptive immunity. The changes of cardiac function in late sepsis are not yet known. MicroRNA-155 (miR-155) is previously found to play important roles in both regulations of immune activation and cardiac function. In this study, C57BL/6 mice were operated to develop into early and late sepsis phases, and miR-155 mimic was injected through the tail vein 48 h after cecal ligation and puncture (CLP). The effect of miR-155 on CLP-induced cardiac dysfunction was explored in late sepsis. We found that increased expression of miR-155 in the myocardium protected against cardiac dysfunction in late sepsis evidenced by attenuating sepsis-reduced cardiac output and enhancing left ventricular systolic function. We also observed that miR-155 markedly reduced the infiltration of macrophages and neutrophils into the myocardium and attenuated the inflammatory response via suppression of JNK signaling pathway. Moreover, overexpression of β-arrestin 2 (Arrb2) exacerbated the mice mortality and immunosuppression in late sepsis. Furthermore, transfection of miR-155 mimic reduced Arrb2 expression, and then restored immunocompetence and improved survival in late septic mice. We conclude that increased miR-155 expression through systemic administration of miR-155 mimic attenuates cardiac dysfunction and improves late sepsis survival by targeting JNK associated inflammatory signaling and Arrb2 mediated immunosuppression.

First-Principles Study on the Structural Stability and Segregation Behavior of γ-Fe/Cr2N Interface with Alloying Additives M (M = Mn, V, Ti, Mo, and Ni

Directory of Open Access Journals (Sweden)

Hui Huang

2016-07-01

Full Text Available This study investigated the structural stability and electrochemical properties of alloying additives M (M = Mn, V, Ti, Mo, or Ni at the γ-Fe(111/Cr2N(0001 interface by the first-principles method. Results indicated that V and Ti were easily segregated at the γ-Fe(111/Cr2N(0001 interface and enhanced interfacial adhesive strength. By contrast, Ni and Mo were difficult to segregate at the γ-Fe(111/Cr2N(0001 interface. Moreover, the results of the work function demonstrated that alloying additives Mn reduced local electrochemical corrosion behavior of the γ-Fe(111/Cr2N(0001 interface by cutting down Volta potential difference (VPD between clean γ-Fe(111 and Cr2N(0001, while alloying additives V, Ti, Mo, and Ni at the γ-Fe(111/Cr2N(0001 interface magnified VPD between clean γ-Fe(111 and Cr2N(0001, which were low-potential sites that usually serve as local attack initiation points.

Silicon Alloying On Aluminium Based Alloy Surface

International Nuclear Information System (INIS)

Suryanto

2002-01-01

Silicon alloying on surface of aluminium based alloy was carried out using electron beam. This is performed in order to enhance tribological properties of the alloy. Silicon is considered most important alloying element in aluminium alloy, particularly for tribological components. Prior to silicon alloying. aluminium substrate were painted with binder and silicon powder and dried in a furnace. Silicon alloying were carried out in a vacuum chamber. The Silicon alloyed materials were assessed using some techniques. The results show that silicon alloying formed a composite metal-non metal system in which silicon particles are dispersed in the alloyed layer. Silicon content in the alloyed layer is about 40% while in other place is only 10.5 %. The hardness of layer changes significantly. The wear properties of the alloying alloys increase. Silicon surface alloying also reduced the coefficient of friction for sliding against a hardened steel counter face, which could otherwise be higher because of the strong adhesion of aluminium to steel. The hardness of the silicon surface alloyed material dropped when it underwent a heating cycle similar to the ion coating process. Hence, silicon alloying is not a suitable choice for use as an intermediate layer for duplex treatment

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

International Nuclear Information System (INIS)

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

1978-01-01

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

miR-155 Deletion in Mice Overcomes Neuron-Intrinsic and Neuron-Extrinsic Barriers to Spinal Cord Repair.

Science.gov (United States)

Gaudet, Andrew D; Mandrekar-Colucci, Shweta; Hall, Jodie C E; Sweet, David R; Schmitt, Philipp J; Xu, Xinyang; Guan, Zhen; Mo, Xiaokui; Guerau-de-Arellano, Mireia; Popovich, Phillip G

2016-08-10

Axon regeneration after spinal cord injury (SCI) fails due to neuron-intrinsic mechanisms and extracellular barriers including inflammation. microRNA (miR)-155-5p is a small, noncoding RNA that negatively regulates mRNA translation. In macrophages, miR-155-5p is induced by inflammatory stimuli and elicits a response that could be toxic after SCI. miR-155 may also independently alter expression of genes that regulate axon growth in neurons. Here, we hypothesized that miR-155 deletion would simultaneously improve axon growth and reduce neuroinflammation after SCI by acting on both neurons and macrophages. New data show that miR-155 deletion attenuates inflammatory signaling in macrophages, reduces macrophage-mediated neuron toxicity, and increases macrophage-elicited axon growth by ∼40% relative to control conditions. In addition, miR-155 deletion increases spontaneous axon growth from neurons; adult miR-155 KO dorsal root ganglion (DRG) neurons extend 44% longer neurites than WT neurons. In vivo, miR-155 deletion augments conditioning lesion-induced intraneuronal expression of SPRR1A, a regeneration-associated gene; ∼50% more injured KO DRG neurons expressed SPRR1A versus WT neurons. After dorsal column SCI, miR-155 KO mouse spinal cord has reduced neuroinflammation and increased peripheral conditioning-lesion-enhanced axon regeneration beyond the epicenter. Finally, in a model of spinal contusion injury, miR-155 deletion improves locomotor function at postinjury times corresponding with the arrival and maximal appearance of activated intraspinal macrophages. In miR-155 KO mice, improved locomotor function is associated with smaller contusion lesions and decreased accumulation of inflammatory macrophages. Collectively, these data indicate that miR-155 is a novel therapeutic target capable of simultaneously overcoming neuron-intrinsic and neuron-extrinsic barriers to repair after SCI. Axon regeneration after spinal cord injury (SCI) fails due to neuron

miR-155 Deletion in Mice Overcomes Neuron-Intrinsic and Neuron-Extrinsic Barriers to Spinal Cord Repair

Science.gov (United States)

Mandrekar-Colucci, Shweta; Hall, Jodie C.E.; Sweet, David R.; Schmitt, Philipp J.; Xu, Xinyang; Guan, Zhen; Mo, Xiaokui; Guerau-de-Arellano, Mireia

2016-01-01

Axon regeneration after spinal cord injury (SCI) fails due to neuron-intrinsic mechanisms and extracellular barriers including inflammation. microRNA (miR)-155–5p is a small, noncoding RNA that negatively regulates mRNA translation. In macrophages, miR-155-5p is induced by inflammatory stimuli and elicits a response that could be toxic after SCI. miR-155 may also independently alter expression of genes that regulate axon growth in neurons. Here, we hypothesized that miR-155 deletion would simultaneously improve axon growth and reduce neuroinflammation after SCI by acting on both neurons and macrophages. New data show that miR-155 deletion attenuates inflammatory signaling in macrophages, reduces macrophage-mediated neuron toxicity, and increases macrophage-elicited axon growth by ∼40% relative to control conditions. In addition, miR-155 deletion increases spontaneous axon growth from neurons; adult miR-155 KO dorsal root ganglion (DRG) neurons extend 44% longer neurites than WT neurons. In vivo, miR-155 deletion augments conditioning lesion-induced intraneuronal expression of SPRR1A, a regeneration-associated gene; ∼50% more injured KO DRG neurons expressed SPRR1A versus WT neurons. After dorsal column SCI, miR-155 KO mouse spinal cord has reduced neuroinflammation and increased peripheral conditioning-lesion-enhanced axon regeneration beyond the epicenter. Finally, in a model of spinal contusion injury, miR-155 deletion improves locomotor function at postinjury times corresponding with the arrival and maximal appearance of activated intraspinal macrophages. In miR-155 KO mice, improved locomotor function is associated with smaller contusion lesions and decreased accumulation of inflammatory macrophages. Collectively, these data indicate that miR-155 is a novel therapeutic target capable of simultaneously overcoming neuron-intrinsic and neuron-extrinsic barriers to repair after SCI. SIGNIFICANCE STATEMENT Axon regeneration after spinal cord injury (SCI) fails

MicroRNA-155 acts as a tumor suppressor in colorectal cancer by targeting CTHRC1 in vitro.

Science.gov (United States)

Liu, Jingtian; Chen, Zongyou; Xiang, Jianbin; Gu, Xiaodong

2018-04-01

Colorectal cancer is one of the most common malignancies. Aberrant expressed microRNAs (miRNAs) have been demonstrated to have strong associations with colorectal cancer by repressing their targets. Therefore, miRNAs are thought to have significant promise in the diagnosis and prognosis of colorectal cancer. Previous studies indicated that miR-155 and collagen triple helix repeat containing 1 (CTHRC1) were both involved in pathogenesis of colorectal cancer, but the underlying mechanisms of miR-155 and CTHRC1 are still unknown. The present study aimed to investigate the biological functions of miR-155 and CTHRC1 in colorectal cancer. Reverse transcription-quantitative polymerase chain reaction was used to examine miR-155 and CTHRC1 expression levels. A dual-luciferase reporter assay was applied to verify the target interaction between miR-155 and CTHRC1. Proliferation, cell cycle, apoptosis, cell migration and invasion were measured using the MTT assay, flow cytometry and Transwell assays, respectively. Results showed that miR-155 expression was decreased, but CTHRC1 expression was increased in colorectal cancer tissue and cell lines. Furthermore, it was demonstrated that miR-155 negatively regulated CTHRC1. Additionally, miR-155 overexpression suppressed cell proliferation, induced cell cycle arrest and promoted cell apoptosis, while an inhibitor of miR-155 facilitated cell proliferation and cell cycle and repressed apoptosis. Transwell experiments indicated that miR-155 inhibited the cell migratory and invasive abilities of HT-29 cells, but miR-155 inhibitor enhanced these abilities of HT-29 cells. These results suggested that miR-155 prevented colorectal cancer progression and metastasis via silencing CTHRC1 in vitro , which provides evidence for miR-155 and CTHRC1 as a novel anti-onco molecular target for the treatment of colorectal cancer in the future.

Thermoelectric properties of In-rich InGaN and InN/InGaN superlattices

Directory of Open Access Journals (Sweden)

James (Zi-Jian Ju

2016-04-01

Full Text Available The thermoelectric properties of n-type InGaN alloys with high In-content and InN/InGaN thin film superlattices (SL grown by molecular beam epitaxy are investigated. Room-temperature measurements of the thermoelectric properties reveal that an increasing Ga-content in ternary InGaN alloys (0 < x(Ga < 0.2 yields a more than 10-fold reduction in thermal conductivity (κ without deteriorating electrical conductivity (σ, while the Seebeck coefficient (S increases slightly due to a widening band gap compared to binary InN. Employing InN/InGaN SLs (x(Ga = 0.1 with different periods, we demonstrate that confinement effects strongly enhance electron mobility with values as high as ∼820 cm2/V s at an electron density ne of ∼5×1019 cm−3, leading to an exceptionally high σ of ∼5400 (Ωcm−1. Simultaneously, in very short-period SL structures S becomes decoupled from ne, κ is further reduced below the alloy limit (κ < 9 W/m-K, and the power factor increases to 2.5×10−4 W/m-K2 by more than a factor of 5 as compared to In-rich InGaN alloys. These findings demonstrate that quantum confinement in group-III nitride-based superlattices facilitates improvements of thermoelectric properties over bulk-like ternary nitride alloys.

The influence of alloy composition on residual stresses in heat treated aluminium alloys

Energy Technology Data Exchange (ETDEWEB)

Robinson, J.S., E-mail: jeremy.robinson@ul.ie [Department of Mechanical, Aeronautical and Biomedical Engineering, University of Limerick (Ireland); Redington, W. [Materials and Surface Science Institute, University of Limerick (Ireland)

2015-07-15

The as quenched properties of eight different heat treatable aluminium alloys are related to residual stress magnitudes with the objective being to establish if there is a relationship between the residual stress and the as quenched alloy hardness and strength. Near surface residual stresses were assessed with X-ray diffraction using both the established sin{sup 2}ψ method and the more recent cos α technique. Through thickness residual stresses were also characterised using neutron diffraction. The alloys were chosen to encompass a wide range of strengths. The low to medium strength alloys were 6060 and 6082, medium to high strength 2618A, 2014A, 7075, 7010 and two variants of 7449, while the very high strength alloy was the powder metallurgy alloy N707. To assess the as quenched strength, dynamic hardness and tensile properties were determined from samples tested immediately after quenching to minimise the influence of precipitation hardening by natural aging. In addition, hot hardness measurements were made in situ on samples cooled to simulate quench paths. Within the experimental constraints of the investigation, the distribution of residual stress through the thickness was found to follow the same pattern for all the alloys investigated, varying from tensile in the interior to surface compression. The influence of alloy strength was manifested as a change in the observed residual stress magnitudes, and surface residual stresses were found to vary linearly with as quenched hardness and strength. - Highlights: • As quenched aluminium alloys contain high magnitude residual stresses. • Surface is compressive balance by a tensile core. • As quenched surface residual stress is linear function of alloy strength. • In situ hot hardness demonstrates rapid change in intrinsic hardness during rapid cooling.

Electron Configuration, and Element No.155 of the Periodic Table of Elements

Directory of Open Access Journals (Sweden)

Khazan A.

2011-04-01

Full Text Available Blocks of the Electron Configuration in the atom are considered with taking into account that the electron configuration should cover also element No.155. It is shown that the electron configuration formula of element No.155, in its graphical representation, completely satisfies Gaussian curve.

Manufacturing and characterization of magnesium alloy foils for use as anode materials in rechargeable magnesium ion batteries

Science.gov (United States)

Schloffer, Daniel; Bozorgi, Salar; Sherstnev, Pavel; Lenardt, Christian; Gollas, Bernhard

2017-11-01

The fabrication of thin foils of magnesium for use as anode material in rechargeable magnesium ion batteries is described. In order to improve its workability, the magnesium was alloyed by melting metallurgy with zinc and/or gadolinium, producing saturated solid solutions. The material was extruded to thin foils and rolled to a thickness of approximately 100 μm. The electrochemical behavior of Mg-1.63 wt% Zn, Mg-1.55 wt% Gd and Mg-1.02 wt% Zn-1.01 wt% Gd was studied in (PhMgCl)2-AlCl3/THF electrolyte by cyclic voltammetry and galvanostatic cycling in symmetrical cells. Analysis of the current-potential curves in the Tafel region and the linear region close to the equilibrium potential show almost no effect of the alloying elements on the exchange current densities (5-45 μA/cm2) and the transfer coefficients. Chemical analyses of the alloy surfaces and the electrolyte demonstrate that the alloying elements not only dissolve with the magnesium during the anodic half-cycles, but also re-deposit during the cathodic half-cycles together with the magnesium and aluminum from the electrolyte. Given the negligible corrosion rate in aprotic electrolytes under such conditions, no adverse effects of alloying elements are expected for the performance of magnesium anodes in secondary batteries.

Swelling in several commercial alloys irradiated to very high neutron fluence

International Nuclear Information System (INIS)

Gelles, D.S.; Pintler, J.S.

1984-01-01

Swelling values have been obtained from a set of commercial alloys irradiated in EBR-II to a peak fluence of 2.5 x 10 23 n/cm 2 (E > 0.1 MeV) or approx. 125 dpa covering the range 400 to 650 0 C. The alloys can be ranked for swelling resistance from highest to lowest as follows: the martensitic and ferritic alloys, the niobium based alloys, the precipitation strengthened iron and nickel based alloys, the molybdenum alloys and the austenitic alloys

41 CFR 102-192.155 - What should our agency-wide mail management policy statement cover?

Science.gov (United States)

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What should our agency-wide mail management policy statement cover? 102-192.155 Section 102-192.155 Public Contracts and... REGULATION ADMINISTRATIVE PROGRAMS 192-MAIL MANAGEMENT Other Agency Responsibilities § 102-192.155 What...

Hindered El Transitions in Eu155 and Tb161

International Nuclear Information System (INIS)

Malmskog, Sven G.

1965-02-01

The absolute E1 transition probabilities from the 3/2 + (411), 5/2 - (532) and 7/2 - (523) single particle levels in Eu 155 and Tb 161 have been measured by the method of delayed coincidences. This gave half lives of T 1/2 1/2 = (1.38 ± 0.06) ns for the 104.4 and 246 keV levels in Eu 155 . T 1/2 = (0.84 ± 0.04) ns and T 1/2 161 . The result has been compared with the calculations of a single particle in a deformed potential made by Nilsson

Fabrication of Si3N4 thin films on phynox alloy substrates for electronic applications

Science.gov (United States)

Shankernath, V.; Naidu, K. Lakshun; Krishna, M. Ghanashyam; Padmanabhan, K. A.

2018-04-01

Thin films of Si3N4 are deposited on Phynox alloy substrates using radio frequency magnetron sputtering. The thickness of the films was varied between 80-150 nm by increasing the duration of deposition from 1 to 3 h at a fixed power density and working pressure. X-ray diffraction patterns reveal that the Si3N4 films had crystallized inspite of the substrates not being heated during deposition. This was confirmed using selected area electron diffraction and high resolution transmission electron microscopy also. It is postulated that a low lattice misfit between Si3N4 and Phynox provides energetically favourable conditions for ambient temperature crystallization. The hardness of the films is of the order of 6 to 9 GPa.

In situ synthesized TiB-TiN reinforced Ti6Al4V alloy composite coatings: microstructure, tribological and in-vitro biocompatibility.

Science.gov (United States)

Das, Mitun; Bhattacharya, Kaushik; Dittrick, Stanley A; Mandal, Chitra; Balla, Vamsi Krishna; Sampath Kumar, T S; Bandyopadhyay, Amit; Manna, Indranil

2014-01-01

Wear resistant TiB-TiN reinforced Ti6Al4V alloy composite coatings were deposited on Ti substrate using laser based additive manufacturing technology. Ti6Al4V alloy powder premixed with 5wt% and 15wt% of boron nitride (BN) powder was used to synthesize TiB-TiN reinforcements in situ during laser deposition. Influences of laser power, scanning speed and concentration of BN on the microstructure, mechanical, in vitro tribological and biological properties of the coatings were investigated. Microstructural analysis of the composite coatings showed that the high temperature generated due to laser interaction with Ti6Al4V alloy and BN results in situ formation of TiB and TiN phases. With increasing BN concentration, from 5wt% to 15wt%, the Young's modulus of the composite coatings, measured by nanoindentation, increased from 170±5GPa to 204±14GPa. In vitro tribological tests showed significant increase in the wear resistance with increasing BN concentration. Under identical test conditions TiB-TiN composite coatings with 15wt% BN exhibited an order of magnitude less wear rate than CoCrMo alloy-a common material for articulating surfaces of orthopedic implants. Average top surface hardness of the composite coatings increased from 543±21HV to 877±75HV with increase in the BN concentration. In vitro biocompatibility and flow cytometry study showed that these composite coatings were non-toxic, exhibit similar cell-materials interactions and biocompatibility as that of commercially pure titanium (CP-Ti) samples. In summary, excellent in vitro wear resistance, high stiffness and suitable biocompatibility make these composite coatings as a potential material for load-bearing articulating surfaces towards orthopaedic implants. © 2013 Elsevier Ltd. All rights reserved.

Electron Configuration, and Element No.155 of the Periodic Table of Elements

Directory of Open Access Journals (Sweden)

Khazan A.

2011-04-01

Full Text Available Blocks of the Electron Configuration in the atom are considered with taking into ac- count that the electron configuration should cover also element No.155. It is shown that the electron configuration formula of element No.155, in its graphical representation, completely satisfies Gaussian curve.

Effect of nitrogen addition and annealing temperature on superelastic properties of Ti-Nb-Zr-Ta alloys

Energy Technology Data Exchange (ETDEWEB)

Tahara, Masaki [Institute of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Kim, Hee Young, E-mail: heeykim@ims.tsukuba.ac.jp [Institute of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Hosoda, Hideki [Precision and Intelligence Laboratory, Tokyo Institute of Technology, Yokohama 226-8503 (Japan); Nam, Tae-hyun [School of Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processingnd ERI, Gyeongsang National University, 900 Gazwadong, Jinju, Gyeongnam 660-701 (Korea, Republic of); Miyazaki, Shuichi, E-mail: miyazaki@ims.tsukuba.ac.jp [Institute of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); School of Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processingnd ERI, Gyeongsang National University, 900 Gazwadong, Jinju, Gyeongnam 660-701 (Korea, Republic of)

2010-10-15

Research highlights: In this study, the effects of composition and annealing temperature on microstructure, shape memory effect and superelastic properties were investigated in Ti-Nb-4Zr-2Ta-N alloys by measuring stress-strain curves at various temperatures and using transmission electron microscopy. Dissolution of {alpha} phase increases M{sub s} and decreases the critical stress for slip for the Ti-22Nb-4Zr-2Ta alloy while it causes the decrease of M{sub s} and the increase of the critical stress for slip for the Ti-20Nb-4Zr-2Ta-0.6N alloy. The different effect of dissolution of {alpha} phase can be attributed to the fact that N is absorbed in {alpha} phase. - Abstract: The composition dependence of the mechanical properties and martensitic transformation behavior of Ti-Nb-4Zr-2Ta-N alloys is investigated. The effect of annealing temperature on the microstructural evolution and superelastic properties in the N-added and N-free alloys is compared. The addition of N decreases M{sub s} of Ti-Nb-4Zr-2Ta alloys by about 200 K per 1 at.%N and improves the superelastic properties of Ti-Nb-4Zr-2Ta alloys. The dissolution of {alpha} phase increases the martensitic transformation start temperature and decreases the superelastic recovery strain for the N-free alloy, whereas it causes opposite effects for the N-added alloy. The different annealing temperature dependences of superelastic properties are discussed on the basis of microstructure observation.

Effect of nitrogen addition and annealing temperature on superelastic properties of Ti-Nb-Zr-Ta alloys

International Nuclear Information System (INIS)

Tahara, Masaki; Kim, Hee Young; Hosoda, Hideki; Nam, Tae-hyun; Miyazaki, Shuichi

2010-01-01

Research highlights: In this study, the effects of composition and annealing temperature on microstructure, shape memory effect and superelastic properties were investigated in Ti-Nb-4Zr-2Ta-N alloys by measuring stress-strain curves at various temperatures and using transmission electron microscopy. Dissolution of α phase increases M s and decreases the critical stress for slip for the Ti-22Nb-4Zr-2Ta alloy while it causes the decrease of M s and the increase of the critical stress for slip for the Ti-20Nb-4Zr-2Ta-0.6N alloy. The different effect of dissolution of α phase can be attributed to the fact that N is absorbed in α phase. - Abstract: The composition dependence of the mechanical properties and martensitic transformation behavior of Ti-Nb-4Zr-2Ta-N alloys is investigated. The effect of annealing temperature on the microstructural evolution and superelastic properties in the N-added and N-free alloys is compared. The addition of N decreases M s of Ti-Nb-4Zr-2Ta alloys by about 200 K per 1 at.%N and improves the superelastic properties of Ti-Nb-4Zr-2Ta alloys. The dissolution of α phase increases the martensitic transformation start temperature and decreases the superelastic recovery strain for the N-free alloy, whereas it causes opposite effects for the N-added alloy. The different annealing temperature dependences of superelastic properties are discussed on the basis of microstructure observation.

Structural and tribological properties of CrTiAlN coatings on Mg alloy by closed-field unbalanced magnetron sputtering ion plating

International Nuclear Information System (INIS)

Shi Yongjing; Long Siyuan; Yang Shicai; Pan Fusheng

2008-01-01

In this paper, a series of multi-layer hard coating system of CrTiAlN has been prepared by closed-field unbalanced magnetron sputtering ion plating (CFUBMSIP) technique in a gas mixture of Ar + N 2 . The coatings were deposited onto AZ31 Mg alloy substrates. During deposition step, technological temperature and metallic atom concentration of coatings were controlled by adjusting the currents of different metal magnetron targets. The nitrogen level was varied by using the feedback control of plasma optical emission monitor (OEM). The structural, mechanical and tribological properties of coatings were characterized by means of X-ray photoelectron spectrometry, high-resolution transmission electron microscope, field emission scanning electron microscope (FESEM), micro-hardness tester, and scratch and ball-on-disc tester. The experimental results show that the N atomic concentration increases and the oxide on the top of coatings decreases; furthermore the modulation period and the friction coefficient decrease with the N 2 level increasing. The outstanding mechanical property can be acquired at medium N 2 level, and the CrTiAlN coatings on AZ31 Mg alloy substrates outperform the uncoated M42 high speed steel (HSS) and the uncoated 316 stainless steel (SS)

Microstructure and mechanical properties of nanostructure multilayer CrN/Cr coatings on titanium alloy

International Nuclear Information System (INIS)

Wiecinski, Piotr; Smolik, Jerzy; Garbacz, Halina; Kurzydlowski, Krzysztof J.

2011-01-01

Five different nanostructured, multilayer coatings (CrN/Cr)x8 with different thickness ratio of Cr and CrN layers were deposited by PAPVD (Plasma Assisted Physical Vapour Deposition) vacuum arc method on Ti6Al4V titanium alloy. The microstructure, chemical and phase composition of the CrN and Cr sub-layers were characterized by SEM with EDX and Cs-corrected dedicated STEM on cross-sections prepared by focus ion beam. Besides, hardness and Young's modulus of the (Cr/CrN)x8 coatings has been measured. The adhesion has been tested by scratch test method. The obtained (CrN/Cr) multilayer coatings, 5-6 μm in thickness, have homogeneous and nanocrystalline structure, free of pores and cracks. The microstructures of Cr and CrN layers consist of columnar grains below 100 nm in diameter. The hardness and Young's modulus of these coatings depend linearly on thickness ratio of Cr and CrN layers. The decrease of the thickness ratio Cr/CrN 0.81 to 0.15 results in the increase of hardness from 1275 HV to 1710 HV and Young's modulus from 260 GPa to 271 GPa.

MicroRNA-155 Modulates Acute Graft-versus-Host Disease by Impacting T Cell Expansion, Migration, and Effector Function.

Science.gov (United States)

Zitzer, Nina C; Snyder, Katiri; Meng, Xiamoei; Taylor, Patricia A; Efebera, Yvonne A; Devine, Steven M; Blazar, Bruce R; Garzon, Ramiro; Ranganathan, Parvathi

2018-06-15

MicroRNA-155 (miR-155) is a small noncoding RNA critical for the regulation of inflammation as well as innate and adaptive immune responses. MiR-155 has been shown to be dysregulated in both donor and recipient immune cells during acute graft-versus-host disease (aGVHD). We previously reported that miR-155 is upregulated in donor T cells of mice and humans with aGVHD and that mice receiving miR-155-deficient (miR155 -/- ) splenocytes had markedly reduced aGVHD. However, molecular mechanisms by which miR-155 modulates T cell function in aGVHD have not been fully investigated. We identify that miR-155 expression in both donor CD8 + T cells and conventional CD4 + CD25 - T cells is pivotal for aGVHD pathogenesis. Using murine aGVHD transplant experiments, we show that miR-155 strongly impacts alloreactive T cell expansion through multiple distinct mechanisms, modulating proliferation in CD8 + donor T cells and promoting exhaustion in donor CD4 + T cells in both the spleen and colon. Additionally, miR-155 drives a proinflammatory Th1 phenotype in donor T cells in these two sites, and miR-155 -/- donor T cells are polarized toward an IL-4-producing Th2 phenotype. We further demonstrate that miR-155 expression in donor T cells regulates CCR5 and CXCR4 chemokine-dependent migration. Notably, we show that miR-155 expression is crucial for donor T cell infiltration into multiple target organs. These findings provide further understanding of the role of miR-155 in modulating aGVHD through T cell expansion, effector cytokine production, and migration. Copyright © 2018 by The American Association of Immunologists, Inc.

32 CFR 155.2 - Applicability and scope.

Science.gov (United States)

2010-07-01

... National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE SECURITY DEFENSE INDUSTRIAL PERSONNEL SECURITY CLEARANCE PROGRAM § 155.2 Applicability and scope. This part: (a) Applies to the Office.... (20) United States Trade Representative. (c) Applies to cases that the Defense Industrial Security...

Early diagnostic role of PSA combined miR-155 detection in prostate cancer.

Science.gov (United States)

Guo, T; Wang, X-X; Fu, H; Tang, Y-C; Meng, B-Q; Chen, C-H

2018-03-01

As a kind of malignant tumor in the male genitourinary system, prostate cancer exhibits significantly increased occurrence. Prostate-specific antigen (PSA) expression can be seen in the prostate cancer, prostatitis, and other diseases, therefore, lack of diagnostic specificity. The miR-155 expression is abnormally increased in the tumors. Therefore, this study aims to explore the clinical significance of PSA combined miR-155 detection in the early diagnosis of prostate cancer. A total of 86 patients diagnosed with prostate cancer were enrolled in this study. PSA and miR-155 gene expression in tumor tissue were detected by using Real-time PCR. The serum levels of PSA were measured by using enzyme-linked immunosorbent assay (ELISA). The correlation of PSA and miR-155 expression with age, body mass index (BMI), tumor volume, tumor-node-metastasis (TNM) stage, lymph node metastasis (LNM), and other clinicopathological features were analyzed, respectively. Serum PSA expression and PSA gene in tumor tissue were significantly higher compared to that in adjacent tissues (pPSA gene and protein increased significantly with the clinical stage of TNM and decreased following the increase of grade (pPSA and miR-155 expressions were positively correlated with TNM stage, tumor volume, and LNM, and negatively correlated with grade (pPSA and miR-155 were closely related to the clinicopathological features of prostate cancer. Combined detection is helpful for the early diagnosis of prostate cancer.

STAT5-mediated expression of oncogenic miR-155 in cutaneous T-cell lymphoma

DEFF Research Database (Denmark)

Kopp, Katharina L; Ralfkiaer, Ulrik; Gjerdrum, Lise Mette R

2013-01-01

show that malignant T cells constitutively express high levels of miR-155 and its host gene BIC (B cell integration cluster). Using ChIP-seq, we identify BIC as a target of transcription factor STAT5, which is aberrantly activated in malignant T cells and induced by IL-2/IL-15 in non-malignant T cells...... of BIC/miR-155 expression by STAT5 is highly specific. Malignant proliferation is significantly inhibited by an antisense-miR-155 as well as by knockdown of STAT5 and BIC.   In conclusion, we provide the first evidence that STAT5 drives expression of oncogenic BIC/miR-155 in cancer. Moreover, our data...

Effect of aging on the martensitic transformation temperature in Ag-Zn-Al alloys

International Nuclear Information System (INIS)

Takezawa, K.; Hoshi, H.; Marukawa, K.

2000-01-01

The relation between atomic ordering and martensitic transformation temperature, M s , in Ag-Zn-Al alloys was examined mainly by means of electrical resistivity measurements. Disordered bcc phase was frozen-in by quenching from a temperature above the critical temperature for ordering, T c . In a Ag-22.3at%Zn-8.9at%Al alloy, the M s temperature has been found to decrease by aging in the parent phase at temperatures between 253 and 293 K. The resistivity also decreased in accord with the M s temperature. This indicates that atomic ordering proceeds by aging. The relation between the decrease in the reverse transformation temperature, A f , and the degree of long range order was obtained. In a Ag-11.0at%Zn-15.5at%Al alloy, in which the M s temperature in the as-quenched state is higher and the T c temperature is lower than that of the former alloy, aging in the martensite phase was performed. In this case, the aging brought about the increase in the A f temperature. This is in contrast to the results of aging in the parent phase. Furthermore, the effect of aging in the parent phase at temperatures higher than T c was examined. Both the transformation temperature and the resistivity were found to become higher. These changes are due to lowering in the degree of short range order. (orig.)

Biocompatibility of metal injection molded versus wrought ASTM F562 (MP35N) and ASTM F1537 (CCM) cobalt alloys.

Science.gov (United States)

Chen, Hao; Sago, Alan; West, Shari; Farina, Jeff; Eckert, John; Broadley, Mark

2011-01-01

We present a comparative analysis between biocompatibility test results of wrought and Metal Injection Molded (MIM) ASTM F562-02 UNS R30035 (MP35N) and F1537 UNS R31538 (CCM) alloy samples that have undergone the same generic orthopedic implant's mechanical, chemical surface pre-treatment, and a designed pre-testing sample preparation method. Because the biocompatibility properties resulting from this new MIM cobalt alloy process are not well understood, we conducted tests to evaluate cytotoxicity (in vitro), hemolysis (in vitro), toxicity effects (in vivo), tissue irritation level (in vivo), and pyrogenicity count (in vitro) on such samples. We show that our developed MIM MP35N and CCM materials and treatment processes are biocompatible, and that both the MIM and wrought samples, although somewhat different in microstructure and surface, do not show significant differences in biocompatibility.

N-cadherin+ HSCs in fetal liver exhibit higher long-term bone marrow reconstitution activity than N-cadherin− HSCs

International Nuclear Information System (INIS)

Toyama, Hirofumi; Arai, Fumio; Hosokawa, Kentaro; Ikushima, Yoshiko Matsumoto; Suda, Toshio

2012-01-01

Highlights: ► High N-cad expression was detected in E12.5 mouse FL LT-HSCs (EPCR + LSK cells). ► Immunohistochemically, N-cad + HSCs co-localized with sinusoidal ECs (Lyve-1 + cells) in E12.5 FL, but these gradually detached in E15.5 and E18.5 FL. ► N-cad + LSK cells in E12.5 FL exhibited higher LTR activity versus N-cad − LSK cells, which decreased in E15.5 and E18.5. ► N-cad expression may confer high LTR activity to HSCs by facilitating interactions with the perisinusoidal niche in FL. -- Abstract: Adult hematopoietic stem cells (HSCs) are maintained in a microenvironment known as the stem cell niche. The regulation of HSCs in fetal liver (FL) and their niche, however, remains to be elucidated. In this study, we investigated the role of N-cadherin (N-cad) in the maintenance of HSCs during FL hematopoiesis. By using anti-N-cad antibodies (Abs) produced by our laboratory, we detected high N-cad expression in embryonic day 12.5 (E12.5) mouse FL HSCs, but not in E15.5 and E18.5 FL. Immunofluorescence staining revealed that N-cad + c-Kit + and N-cad + endothelial protein C receptor (EPCR) + HSCs co-localized with Lyve-1 + sinusoidal endothelial cells (ECs) in E12.5 FL and that some of these cells also expressed N-cad. However, N-cad + HSCs were also observed to detach from the perisinusoidal niche at E15.5 and E18.5, concomitant with a down-regulation of N-cad and an up-regulation of E-cadherin (E-cad) in hepatic cells. Moreover, EPCR + long-term (LT)-HSCs were enriched in the N-cad + Lin − Sca-1 + c-Kit + (LSK) fraction in E12.5 FL, but not in E15.5 or E18.5 FL. In a long-term reconstitution (LTR) activity assay, higher engraftment associated with N-cad + LSK cells versus N-cad − LSK cells in E12.5 FL when transplanted into lethally irradiated recipient mice. However, the higher engraftment of N-cad + LSK cells decreased subsequently in E15.5 and E18.5 FL. It is possible that N-cad expression conferred higher LTR activity to HSCs by facilitating

49 CFR 237.155 - Documents and records.

Science.gov (United States)

2010-10-01

..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Documentation, Records, and Audits of Bridge Management Programs § 237.155 Documents and records. Each track owner required to implement a bridge management... protected by a security system that incorporates a user identity and password, or a comparable method, to...

21 CFR 558.155 - Chlortetracycline, sulfathiazole, penicillin.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Chlortetracycline, sulfathiazole, penicillin. 558... Specific New Animal Drugs for Use in Animal Feeds § 558.155 Chlortetracycline, sulfathiazole, penicillin... percent (20 grams) sulfathiazole, and procaine penicillin equivalent to 10 grams of penicillin per pound...

33 CFR 155.2210 - Purpose and applicability.

Science.gov (United States)

2010-07-01

... (CONTINUED) POLLUTION OIL OR HAZARDOUS MATERIAL POLLUTION PREVENTION REGULATIONS FOR VESSELS Response Plan Requirements for Vessels Carrying Other Non-Petroleum Oils as a Primary Cargo § 155.2210 Purpose and applicability. This subpart establishes oil spill response planning requirements for an owner or operator of a...

33 CFR 155.1210 - Purpose and applicability.

Science.gov (United States)

2010-07-01

... (CONTINUED) POLLUTION OIL OR HAZARDOUS MATERIAL POLLUTION PREVENTION REGULATIONS FOR VESSELS Response plan requirements for vessels carrying animal fats and vegetable oils as a primary cargo § 155.1210 Purpose and applicability. This subpart establishes oil spill response planning requirements for an owner or operator of a...

MicroRNA-155 deletion promotes tumorigenesis in the azoxymethane-dextran sulfate sodium model of colon cancer

Science.gov (United States)

Velázquez, Kandy T.; Enos, Reilly T.; McClellan, Jamie L.; Cranford, Taryn L.; Chatzistamou, Ioulia; Singh, Udai P.; Nagarkatti, Mitzi; Nagarkatti, Prakash S.; Fan, Daping

2016-01-01

Clinical studies have linked microRNA-155 (miR-155) expression in the tumor microenvironment to poor prognosis. However, whether miR-155 upregulation is predictive of a pro- or antitumorigenic response is unclear, as the limited preclinical data available remain controversial. We examined miR-155 expression in tumor tissue from colon cancer patients. Furthermore, we investigated the role of this microRNA in proliferation and apoptosis, inflammatory processes, immune cell populations, and transforming growth factor-β/SMAD signaling in a chemically induced (azoxymethane-dextran sulfate sodium) mouse model of colitis-associated colon cancer. We found a higher expression of miR-155 in the tumor region than in nontumor colon tissue of patients with colon cancer. Deletion of miR-155 in mice resulted in a greater number of polyps/adenomas, an increased symptom severity score, a higher grade of epithelial dysplasia, and a decrease in survival. Surprisingly, these findings were associated with an increase in apoptosis in the normal mucosa, but there was no change in proliferation. The protumorigenic effects of miR-155 deletion do not appear to be driven solely by dysregulation of inflammation, as both genotypes had relatively similar levels of inflammatory mediators. The enhanced tumorigenic response in miR-155−/− mice was associated with alterations in macrophages and neutrophils, as markers for these populations were decreased and increased, respectively. Furthermore, we demonstrated a greater activation of the transforming growth factor-β/SMAD pathway in miR-155−/− mice, which was correlated with the increased tumorigenesis. Given the multiple targets of miR-155, careful evaluation of its role in tumorigenesis is necessary prior to any consideration of its potential as a biomarker and/or therapeutic target in colon cancer. PMID:26744471

Effect of Solution Treatment on Precipitation Behaviors, Age Hardening Response and Creep Properties of Elektron21 Alloy Reinforced by AlN Nanoparticles.

Science.gov (United States)

Saboori, Abdollah; Padovano, Elisa; Pavese, Matteo; Dieringa, Hajo; Badini, Claudio

2017-12-02

In the present study, the solution and ageing treatments behavior of Mg-RE-Zr-Zn alloy (Elektron21) and its nano-AlN reinforced nanocomposites have been evaluated. The properties of the thermal-treated materials were investigated in terms of Vickers hardness, the area fraction of precipitates, microstructure and phase composition. The solution treatments were performed by treating at 520 °C, 550 °C and 580 °C in argon atmosphere. The outcomes show that the hardness of the solutionized alloys was slightly affected by the solution temperature. X-ray diffraction and image analysis revealed that the complete dissolution of precipitates was not possible, neither for Elektron21 (El21) nor for its AlN containing nanocomposites. The ageing treatment of El21 led to a significant improvement in hardness after 20 h, while for longer times, it progressively decreased. The effect of ageing on the hardness of El21-AlN composites was found to be much less than this effect on the hardness of the host alloy. Electron backscatter diffraction (EBSD) analysis of El21 and El21-1%AlN after solution treatment confirm the random orientation of grains with a typical texture of random distribution. The as-cast creep results showed that the incorporation of nanoparticles could effectively improve the creep properties, while the results after solution treatment at 520 °C for 12 h followed by ageing treatment at 200 °C for 20 h confirmed that the minimum creep rate of T6-El21 was almost equal to the as-cast El21-AlN.

Pre-Columbian alloys from the royal tombs of Sipán; energy dispersive X-ray fluorescence analysis with a portable equipment.

Science.gov (United States)

Cesareo, R; Calza, C; Dos Anjos, M; Lopes, R T; Bustamante, A; Fabian S, J; Alva, W; Chero Z, L

2010-01-01

On the north coast of present-day Peru flourished approximately between 50 and 700 AD, the Moche civilization. It was an advanced culture and the Moche were sophisticated metalsmiths, so that they are considered as the finest producers of jewels and artefacts of the region. The Moche metalworking ability was impressively demonstrated by the objects discovered by Walter Alva and coworkers in 1987, in the excavations of the "Tumbas Reales de Sipán". About 50 metal objects from these excavations, now at the namesake Museum, in Lambayeque, north of Peru, were analyzed with a portable equipment using energy-dispersive X-ray fluorescence. This portable equipment is mainly composed of a small size X-ray tube and a thermoelectrically cooled X-ray detector. Standard samples of gold and silver alloys were employed for quantitative analysis. It was determined that the analyzed artefacts from the "Tumbas Reales de Sipán" are mainly composed of gold, silver and copper alloys, of gilded copper and of tumbaga, the last being a poor gold alloy enriched at the surface by depletion gilding, i.e. removing copper from the surface. Copyright 2009 Elsevier Ltd. All rights reserved.

17 CFR 155.6 - Trading standards for the transaction of business on registered derivatives transaction execution...

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Trading standards for the transaction of business on registered derivatives transaction execution facilities. 155.6 Section 155.6 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION TRADING STANDARDS § 155.6 Trading...

The effect of PVD coatings on the corrosion behaviour of AZ91 magnesium alloy

International Nuclear Information System (INIS)

Altun, Hikmet; Sen, Sadri

2006-01-01

In this study, multilayered AlN (AlN + AlN + AlN) and AlN + TiN were coated on AZ91 magnesium alloy using physical vapour deposition (PVD) technique of DC magnetron sputtering, and the influence of the coatings on the corrosion behaviour of the AZ91 alloy was examined. A PVD system for coating processes, a potentiostat for electrochemical corrosion tests, X-ray difractometer for compositional analysis of the coatings, and scanning electron microscopy for surface examinations were used. It was determined that PVD coatings deposited on AZ91 magnesium alloy increased the corrosion resistance of the alloy, and AlN + AlN + AlN coating increased the corrosion resistance much more than AlN + TiN coating. However, it was observed that, in the coating layers, small structural defects e.g., pores, pinholes, cracks that could arise from the coating process or substrate and get the ability of protection from corrosion worsened were present

Study of PVD AlCrN Coating for Reducing Carbide Cutting Tool Deterioration in the Machining of Titanium Alloys.

Science.gov (United States)

Cadena, Natalia L; Cue-Sampedro, Rodrigo; Siller, Héctor R; Arizmendi-Morquecho, Ana M; Rivera-Solorio, Carlos I; Di-Nardo, Santiago

2013-05-24

The manufacture of medical and aerospace components made of titanium alloys and other difficult-to-cut materials requires the parallel development of high performance cutting tools coated with materials capable of enhanced tribological and resistance properties. In this matter, a thin nanocomposite film made out of AlCrN (aluminum-chromium-nitride) was studied in this research, showing experimental work in the deposition process and its characterization. A heat-treated monolayer coating, competitive with other coatings in the machining of titanium alloys, was analyzed. Different analysis and characterizations were performed on the manufactured coating by scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDXS), and X-ray diffraction (XRD). Furthermore, the mechanical behavior of the coating was evaluated through hardness test and tribology with pin-on-disk to quantify friction coefficient and wear rate. Finally, machinability tests using coated tungsten carbide cutting tools were executed in order to determine its performance through wear resistance, which is a key issue of cutting tools in high-end cutting at elevated temperatures. It was demonstrated that the specimen (with lower friction coefficient than previous research) is more efficient in machinability tests in Ti6Al4V alloys. Furthermore, the heat-treated monolayer coating presented better performance in comparison with a conventional monolayer of AlCrN coating.

Contact Behavior of Composite CrTiSiN Coated Dies in Compressing of Mg Alloy Sheets under High Pressure

Directory of Open Access Journals (Sweden)

T.S. Yang

2018-01-01

Full Text Available Hard coatings have been adopted in cutting and forming applications for nearly two decades. The major purpose of using hard coatings is to reduce the friction coefficient between contact surfaces, to increase strength, toughness and anti-wear performance of working tools and molds, and then to obtain a smooth work surface and an increase in service life of tools and molds. In this report, we deposited a composite CrTiSiN hard coating, and a traditional single-layered TiAlN coating as a reference. Then, the coatings were comparatively studied by a series of tests. A field emission SEM was used to characterize the microstructure. Hardness was measured using a nano-indentation tester. Adhesion of coatings was evaluated using a Rockwell C hardness indentation tester. A pin-on-disk wear tester with WC balls as sliding counterparts was used to determine the wear properties. A self-designed compression and friction tester, by combining a Universal Testing Machine and a wear tester, was used to evaluate the contact behavior of composite CrTiSiN coated dies in compressing of Mg alloy sheets under high pressure. The results indicated that the hardness of composite CrTiSiN coating was lower than that of the TiAlN coating. However, the CrTiSiN coating showed better anti-wear performance. The CrTiSiN coated dies achieved smooth surfaces on the Mg alloy sheet in the compressing test and lower friction coefficient in the friction test, as compared with the TiAlN coating.

Contact Behavior of Composite CrTiSiN Coated Dies in Compressing of Mg Alloy Sheets under High Pressure.

Science.gov (United States)

Yang, T S; Yao, S H; Chang, Y Y; Deng, J H

2018-01-08

Hard coatings have been adopted in cutting and forming applications for nearly two decades. The major purpose of using hard coatings is to reduce the friction coefficient between contact surfaces, to increase strength, toughness and anti-wear performance of working tools and molds, and then to obtain a smooth work surface and an increase in service life of tools and molds. In this report, we deposited a composite CrTiSiN hard coating, and a traditional single-layered TiAlN coating as a reference. Then, the coatings were comparatively studied by a series of tests. A field emission SEM was used to characterize the microstructure. Hardness was measured using a nano-indentation tester. Adhesion of coatings was evaluated using a Rockwell C hardness indentation tester. A pin-on-disk wear tester with WC balls as sliding counterparts was used to determine the wear properties. A self-designed compression and friction tester, by combining a Universal Testing Machine and a wear tester, was used to evaluate the contact behavior of composite CrTiSiN coated dies in compressing of Mg alloy sheets under high pressure. The results indicated that the hardness of composite CrTiSiN coating was lower than that of the TiAlN coating. However, the CrTiSiN coating showed better anti-wear performance. The CrTiSiN coated dies achieved smooth surfaces on the Mg alloy sheet in the compressing test and lower friction coefficient in the friction test, as compared with the TiAlN coating.

Electrochemical Impedance Spectroscopy Of Metal Alloys

Science.gov (United States)

Macdowell, L. G.; Calle, L. M.

1993-01-01

Report describes use of electrochemical impedance spectroscopy (EIS) to investigate resistances of 19 alloys to corrosion under conditions similar to those of corrosive, chloride-laden seaside environment of Space Transportation System launch site. Alloys investigated: Hastelloy C-4, C-22, C-276, and B-2; Inconel(R) 600, 625, and 825; Inco(R) G-3; Monel 400; Zirconium 702; Stainless Steel 304L, 304LN, 316L, 317L, and 904L; 20Cb-3; 7Mo+N; ES2205; and Ferralium 255. Results suggest electrochemical impedance spectroscopy used to predict corrosion performances of metal alloys.

Microstructure and high-temperature oxidation resistance of TiN/Ti3Al intermetallic matrix composite coatings on Ti6Al4V alloy surface by laser cladding

Science.gov (United States)

Zhang, Xiaowei; Liu, Hongxi; Wang, Chuanqi; Zeng, Weihua; Jiang, Yehua

2010-11-01

A high-temperature oxidation resistant TiN embedded in Ti3Al intermetallic matrix composite coating was fabricated on titanium alloy Ti6Al4V surface by 6kW transverse-flow CO2 laser apparatus. The composition, morphology and microstructure of the laser clad TiN/Ti3Al intermetallic matrix composite coating were characterized by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). In order to evaluate the high-temperature oxidation resistance of the composite coatings and the titanium alloy substrate, isothermal oxidation test was performed in a conventional high-temperature resistance furnace at 600°C and 800°C respectively. The result shows that the laser clad intermetallic composite coating has a rapidly solidified fine microstructure consisting of TiN primary phase (granular-like, flake-like, and dendrites), and uniformly distributed in the Ti3Al matrix. It indicates that a physical and chemical reaction between the Ti powder and AlN powder occurred completely under the laser irradiation. In addition, the microhardness of the TiN/Ti3Al intermetallic matrix composite coating is 844HV0.2, 3.4 times higher than that of the titanium alloy substrate. The high-temperature oxidation resistance test reveals that TiN/Ti3Al intermetallic matrix composite coating results in the better modification of high-temperature oxidation behavior than the titanium substrate. The excellent high-temperature oxidation resistance of the laser cladding layer is attributed to the formation of the reinforced phase TiN and Al2O3, TiO2 hybrid oxide. Therefore, the laser cladding TiN/Ti3Al intermetallic matrix composite coating is anticipated to be a promising oxidation resistance surface modification technique for Ti6Al4V alloy.

Preparation of hard magnetic materials based on nitrogenated rare-earth iron alloys

International Nuclear Information System (INIS)

Guilherme, Eneida da Graca

1999-01-01

Nd Fe 11 Ti, Nd Fe 10.5 Mo 1.5 and Nd Fe 10.75 Mo 1.25 alloys were synthesized by reduction-diffusion calciothermic process (RDC) from neodymium chloride (NdCl 3 ), iron, titanium, molybdenum and reduction agent (metallic calcium). The effect of process variables, like temperature, time, excess amount of NdCl 3 , heating rate, and composition variation of the Nd Fe 12-x Mo x (1 ≥ x ≥ 2). Mother alloys in which 1:12 phase is major were nitrogenated by gas-solid reaction with N 2 and by chemical reaction with sodium zide (Na N 3 ). In addition, the influence of reducing particle size of the powdered mother alloys in the nitrogenation step with Na N 3 were studied. As prepared and interstitially modified Nd Fe 11 Ti, Nd Fe 10.5 Mo 1.5 and Nd Fe 10.75 Mo 1.25 alloys with nitrogen , were characterized by X-ray diffraction, Moessbauer spectroscopy, thermomagnetic, SEM and EDS. Nitrogenation by gas-solid reaction with N 2 is found to be not promising, since resulted Curie temperatures (Tc) were lower than literature values. However, nitrogenation by chemical reaction with Na N 3 was efficient with higher or same Tc than previous reported results. The average increases on Tc and volumetric expansion were 200 deg C and 4%, respectively. Milling of the mother alloys before nitrogenation at 330 deg C is preferred because reaction kinetics is enhanced. Nevertheless, at 450 deg C, a competition between the interstitially modified compound formation (alloy + N) and alloy dissociation has occurred, resulting in a Fe-α phase increase. (author)

Behaviour of Tiu-Nb-Ni alloys in sulfuric and hydrochloric acids

International Nuclear Information System (INIS)

Shcherbakov, A.I.; Dorofeeva, V.N.; Tomashov, N.D.; Goncharenko, B.A.; Mikheev, V.S.

1991-01-01

Regularities of corrosion behaviour and passivation of ternary alloys containing 0.2; 0.5, 1,2, 3% Ni and 1,2,3,4,5,6,8 % Nb in 5n. H 2 SO 4 and 5n HCl, i.e. under conditions when unalloyed titanium dissolves actively, are considered. High cathodic efficiency of nickel plays essential role for the ternary alloy transfer to passive state, while a lower cathodic efficiency of niobium is sufficient for the alloy maintaining in the passive state. At the same time high corrosion resistance of niobium (in contract to nickel) undr potentials of titanium passive state promotes stable maintenance of the alloy in the passive state

Fe-Mn-Si based shape memory alloys

International Nuclear Information System (INIS)

Hsu, T.Y.

2000-01-01

Characteristics of martensitic transformation fcc(γ)→hcp(ε) in Fe-Mn-Si based alloys are briefly reviewed. By analyzing the influences of constituents and treatments on shape memory effect (SME) in Fe-Mn-Si, the main factors controlling SME are summarized as austenite strengthening, stacking fault energy (probability) and antiferromagnetic temperature. Contribution of thermomechanical training to SME is introduced. The Fe-Mn-Si-RE (rare earth elements) and Fe-Mn-Si-Cr-N alloys are recommended as two novel shape memory alloys with superior SME. (orig.)

7 CFR 932.155 - Special purpose shipments.

Science.gov (United States)

2010-01-01

... and Regulations § 932.155 Special purpose shipments. (a) The disposition of packaged olives covered by... Service, such packaged olives may be disposed of for use in the production of olive oil or dumped. (2... furnish the committee, upon demand, such evidence of disposition of the packaged olives covered by an...

33 CFR 155.4050 - Ensuring that the salvors and marine firefighters are adequate.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Ensuring that the salvors and marine firefighters are adequate. 155.4050 Section 155.4050 Navigation and Navigable Waters COAST GUARD..., water turbidity, water depth, sea state and temperature extremes). (13) Resource provider has the...

Magnetoimpedance of stress and/or field annealed Fe73.5Cu1Nb3Si15.5B7 amorphous and nanocrystalline ribbon

International Nuclear Information System (INIS)

Miguel, C.; Zhukov, A.P.; Gonzalez, J.

2003-01-01

Magnetoimpedance (MI) response of as-cast and annealed Fe 73.5 Cu 1 Nb 3 Si 15.5 B 7 amorphous alloy ribbon has been investigated. The thermal treatments were performed by current annealing technique (density 45 A/mm 2 during 1-120 min) under the action of a tensile stress of 500 MPa and/or an axial magnetic field of 750 A/m. For short annealing time (less than 5 min), the three kinds of treatment induced an uniaxial magnetic anisotropy in the amorphous state with a maximum of MI of 15%, while for long annealing the nanocrystallization process occurs with larger MI effect of around 22%. This MI behaviour is explained taking into account the role of the induced magnetic anisotropy and the microstructural changes owing to the thermal treatments

CD155/PVR plays a key role in cell motility during tumor cell invasion and migration

International Nuclear Information System (INIS)

Sloan, Kevin E; Ilag, Leodevico L; Jay, Daniel G; Eustace, Brenda K; Stewart, Jean K; Zehetmeier, Carol; Torella, Claudia; Simeone, Marina; Roy, Jennifer E; Unger, Christine; Louis, David N

2004-01-01

Invasion is an important early step of cancer metastasis that is not well understood. Developing therapeutics to limit metastasis requires the identification and validation of candidate proteins necessary for invasion and migration. We developed a functional proteomic screen to identify mediators of tumor cell invasion. This screen couples Fluorophore Assisted Light Inactivation (FALI) to a scFv antibody library to systematically inactivate surface proteins expressed by human fibrosarcoma cells followed by a high-throughput assessment of transwell invasion. Using this screen, we have identified CD155 (the poliovirus receptor) as a mediator of tumor cell invasion through its role in migration. Knockdown of CD155 by FALI or by RNAi resulted in a significant decrease in transwell migration of HT1080 fibrosarcoma cells towards a serum chemoattractant. CD155 was found to be highly expressed in multiple cancer cell lines and primary tumors including glioblastoma (GBM). Knockdown of CD155 also decreased migration of U87MG GBM cells. CD155 is recruited to the leading edge of migrating cells where it colocalizes with actin and αv-integrin, known mediators of motility and adhesion. Knockdown of CD155 also altered cellular morphology, resulting in cells that were larger and more elongated than controls when plated on a Matrigel substrate. These results implicate a role for CD155 in mediating tumor cell invasion and migration and suggest that CD155 may contribute to tumorigenesis

Mechanical and irradiation properties of zirconium alloys irradiated in HANARO

International Nuclear Information System (INIS)

Kwon, Oh Hyun; Eom, Kyong Bo; Kim, Jae Ik; Suh, Jung Min; Jeon, Kyeong Lak

2011-01-01

These experimental studies are carried out to build a database for analyzing fuel performance in nuclear power plants. In particular, this study focuses on the mechanical and irradiation properties of three kinds of zirconium alloy (Alloy A, Alloy B and Alloy C) irradiated in the HANARO (High-flux Advanced Neutron Application Reactor), one of the leading multipurpose research reactors in the world. Yield strength and ultimate tensile strength were measured to determine the mechanical properties before and after irradiation, while irradiation growth was measured for the irradiation properties. The samples for irradiation testing are classified by texture. For the irradiation condition, all samples were wrapped into the capsule (07M-13N) and irradiated in the HANARO for about 100 days (E > 1.0 MeV, 1.1 10 21 n/cm 2 ). These tests and results indicate that the mechanical properties of zirconium alloys are similar whether unirradiated or irradiated. Alloy B has shown the highest yield strength and tensile strength properties compared to other alloys in irradiated condition. Even though each of the zirconium alloys has a different alloying content, this content does not seem to affect the mechanical properties under an unirradiated condition and low fluence. And all the alloys have shown the tendency to increase in yield strength and ultimate tensile strength. Transverse specimens of each of the zirconium alloys have a slightly lower irradiation growth tendency than longitudinal specimens. However, for clear analysis of texture effects, further testing under higher irradiation conditions is needed

IκK-16 decreases miRNA-155 expression and attenuates the human monocyte inflammatory response.

Directory of Open Access Journals (Sweden)

Norman James Galbraith

Full Text Available Excessive inflammatory responses in the surgical patient may result in cellular hypo-responsiveness, which is associated with an increased risk of secondary infection and death. microRNAs (miRNAs, such as miR-155, are powerful regulators of inflammatory signalling pathways including nuclear factor κB (NFκB. Our objective was to determine the effect of IκK-16, a selective blocker of inhibitor of kappa-B kinase (IκK, on miRNA expression and the monocyte inflammatory response. In a model of endotoxin tolerance using primary human monocytes, impaired monocytes had decreased p65 expression with suppressed TNF-α and IL-10 production (P < 0.05. miR-155 and miR-138 levels were significantly upregulated at 17 h in the impaired monocyte (P < 0.05. Notably, IκK-16 decreased miR-155 expression with a corresponding dose-dependent decrease in TNF-α and IL-10 production (P < 0.05, and impaired monocyte function was associated with increased miR-155 and miR-138 expression. In the context of IκK-16 inhibition, miR-155 mimics increased TNF-α production, while miR-155 antagomirs decreased both TNF-α and IL-10 production. These data demonstrate that IκK-16 treatment attenuates the monocyte inflammatory response, which may occur through a miR-155-mediated mechanism, and that IκK-16 is a promising approach to limit the magnitude of an excessive innate inflammatory response to LPS.

Structural changes in heat resisting high nickel alloys during homogenization

International Nuclear Information System (INIS)

Kleshchev, A.S.; Korneeva, N.N.; Yurina, O.M.; Guzej, L.S.

1981-01-01

Effect of homogenization on the structure and technological plasticity of the KhN73MBTYu and KhN62BMKTYu alloys during treatment with pressure is investigated taking into account peculiarities if the phase composition. It is shown that homogenization of the KhN73MBTYu and KhN62BMKTYu alloys increases the technological plasticity. Homogenization efficiency is conditioned by the change of the grain boundaries and carbide morphology as well as by homogeneous distribution of the large γ'-phase [ru

Graph theory and binary alloys passivated by nickel

International Nuclear Information System (INIS)

McCafferty, E.

2005-01-01

The passivity of a nickel binary alloy is considered in terms of a network of -Ni-O-Ni- bridges in the oxide film, where Ni is the component of the binary alloy which produces passivity. The structure of the oxide is represented by a mathematical graph, and graph theory is used to calculate the connectivity of the oxide, given by the product of the number of edges in the graph and the Randic index. A stochastic calculation is employed to insert ions of the second metal into the oxide film so as to disrupt the connectivity of the -Ni-O-Ni- network. This disruption occurs at a critical ionic concentration of the oxide film. Mathematical relationships are developed for the introduction of a general ion B +n into the oxide film, and critical ionic compositions are calculated for oxide films on the nickel binary alloys. The notation B refers to any metal B which produces B +n ions in the oxide film, where +n is the oxidation number of the ion. The results of this analysis for Fe-Ni and Cu-Ni binary alloys are in good agreement with experimental results

42 CFR 417.155 - How the HMO option must be included in the health benefits plan.

Science.gov (United States)

2010-10-01

... printed materials that meet the requirements of § 417.124(b). (ii) Access may not be more restrictive or... benefits plan. 417.155 Section 417.155 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT... Organizations in Employee Health Benefits Plans § 417.155 How the HMO option must be included in the health...

Reaction pathways for reduction of nitrate ions on platinum, rhodium, and platinum-rhodium alloy electrodes

International Nuclear Information System (INIS)

Cunha, M.C.P.M. da; De Souza, J.P.I.; Nart, F.C.

2000-01-01

The reduction of nitrate ions on platinum, rhodium, and platinum-rhodium alloy electrodes has been investigated using differential electrochemical mass spectrometry and in situ FTIR measurements. For 3 M HNO 3 concentration it has been found that nitrate starts the reduction with partial N-O bond dissociation and N-N bond formation generating NO and N 2 O. At potentials lower than 0.2 V the reaction proceeds forming dissolved NH 4 + . For potentials lower than 0 V the reduction continues via a multiple pathway reaction leading to the nonselective production of N 2 , NH 2 OH, and N 2 H 2 . On the alloyed electrodes, the production of NO and N 2 O has been observed in both cathodic and anodic scans, while on pure platinum and rhodium electrodes the reaction has been observed only during the cathodic scan. Contrasting with the pure platinum and rhodium alloys, where the N-O bond break starts forming NO and N 2 O, on the alloys HNO 2 has been observed as the first reaction step. For alloys with higher rhodium composition, like Pt 75 Rh 25 , no N 2 has been detected for potentials lower than 0 V

Anodic dissolution and corrosion of alloy Cu30Ni in chloride solutions

International Nuclear Information System (INIS)

Zolotarev, E.I.

1989-01-01

The anodic and corrosion behavior of alloy Cu30Ni is studied in a solution of 3 N NaCl + 0.01 N HCl by a radiometric method using gamma isotopes of 58 Co (as a marker for Ni) and 64 Cu in combination with electrochemical measurements. It was established that under stationary conditions there was uniform dissolution of the alloy both during free corrosion and anodic polarization. The authors obtained partial anodic dissolution curves for the components of the alloy. It was shown that the dissolution kinetics differed from the mechanisms controlling dissolution of the corresponding pure metals. During corrosion of the alloy in an oxygen atmosphere a back precipitation of copper on the surface of the alloy was not observed. The characteristics observed in the corrosion-electrochemical behavior of the alloy in concentrated chloride solutions can be explained by the presence of Ni on the surface of the dissolving alloy

Laser surface alloying of aluminium-transition metal alloys

International Nuclear Information System (INIS)

Almeida, A.; Vilar, R.

1998-01-01

Laser surface alloying has been used as a tool to produce hard and corrosion resistant Al-transition metal (TM) alloys. Cr and Mo are particularly interesting alloying elements to produce stable high-strength alloys because they present low diffusion coefficients and solid solubility in Al. To produce Al-TM surface alloys a two-step laser process was developed: firstly, the material is alloyed using low scanning speed and secondly, the microstructure is modified by a refinement step. This process was used in the production of Al-Cr, Al-Mo and Al-Mo and Al-Nb surface alloys by alloying Cr, Mo or Nb powder into an Al and 7175 Al alloy substrate using a CO 2 laser . This paper presents a review of the work that has been developed at Instituto Superior Tecnico on laser alloying of Al-TM alloy, over the last years. (Author) 16 refs

Defect properties of InGaAsN layers grown as sub-monolayer digital alloys by molecular beam epitaxy

Science.gov (United States)

Baranov, Artem I.; Gudovskikh, Alexander S.; Kudryashov, Dmitry A.; Lazarenko, Alexandra A.; Morozov, Ivan A.; Mozharov, Alexey M.; Nikitina, Ekaterina V.; Pirogov, Evgeny V.; Sobolev, Maxim S.; Zelentsov, Kirill S.; Egorov, Anton Yu.; Darga, Arouna; Le Gall, Sylvain; Kleider, Jean-Paul

2018-04-01

The defect properties of InGaAsN dilute nitrides grown as sub-monolayer digital alloys (SDAs) by molecular beam epitaxy for photovoltaic application were studied by space charge capacitance spectroscopy. Alloys of i-InGaAsN (Eg = 1.03 eV) were lattice-matched grown on GaAs wafers as a superlattice of InAs/GaAsN with one monolayer of InAs (solar cells. Low p-type background doping was demonstrated at room temperature in samples with InGaAsN layers 900 nm and 1200 nm thick (less 1 × 1015 cm-3). According to admittance spectroscopy and deep-level transient spectroscopy measurements, the SDA approach leads to defect-free growth up to a thickness of 900 nm. An increase in thickness to 1200 nm leads to the formation of non-radiative recombination centers with an activation energy of 0.5 eV (NT = 8.4 × 1014 cm-3) and a shallow defect level at 0.20 eV. The last one leads to the appearance of additional doping, but its concentration is low (NT = 5 × 1014 cm-3) so it does not affect the photoelectric properties. However, further increase in thickness to 1600 nm, leads to significant growth of its concentration to (3-5) × 1015 cm-3, while the concentration of deep levels becomes 1.3 × 1015 cm-3. Therefore, additional free charge carriers appearing due to ionization of the shallow level change the band diagram from p-i-n to p-n junction at room temperature. It leads to a drop of the external quantum efficiency due to the effect of pulling electric field decrease in the p-n junction and an increased number of non-radiative recombination centers that negatively impact lifetimes in InGaAsN.

Microstructure and high temperature oxidation resistance of in-situ synthesized TiN/Ti_3Al intermetallic composite coatings on Ti6Al4V alloy by laser cladding process

International Nuclear Information System (INIS)

Liu, Hongxi; Zhang, Xiaowei; Jiang, Yehua; Zhou, Rong

2016-01-01

High temperature anti-oxidation TiN/Ti_3Al intermetallic composite coatings were fabricated with the powder and AlN powder on Ti6Al4V titanium alloy surface by 6 kW transverse-flow CO_2 laser apparatus. The chemical composition, morphology and microstructure of the TiN/Ti_3Al composite coatings were characterized by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). In order to evaluate the high temperature oxidation resistance of TiN/Ti_3Al coating, the isothermal oxidation test was performed in a high temperature resistance furnace at 600 °C and 800 °C, respectively. The result shows that the composite coating has a rapidly solidified fine microstructure consisting of TiN primary phase (granular-like, flake-like or dendrites), with an even distribution in Ti_3Al matrix. It indicates that a physical and chemical reaction between Ti powder and AlN powder has completely occurred under the laser irradiation condition. In addition, the microhardness of the TiN/Ti3Al intermetallic composite coating is 3.4 times higher than that of the Ti6Al4V alloy substrate and reaches 844 HV_0_._2. The high temperature oxidation behavior test reveals that the high temperature oxidation resistance of TiN/Ti_3Al composite coating is much better than that of titanium alloy substrate. The excellent high temperature oxidation resistance of TiN/Ti_3Al intermetallic composite coating is attributed to the formation of reinforced phases TiN, Al_2O_3 and TiO_2. The laser cladding TiN/Ti_3Al intermetallic composite coating is anticipated to be a promising high temperature oxidation resistance coating for Ti6Al4V alloy. - Highlights: • In-situ TiN/Ti_3Al composite coating was synthesized on Ti6Al4V alloy by laser cladding. • The influence of Ti and AlN molar ratio on the microstructure of the coating was studied. • The TiN/Ti_3Al intermetallic coating is mainly composed of α-Ti, TiN and Ti_3Al phases. • The

MiR-155 promotes cell proliferation and inhibits apoptosis by PTEN signaling pathway in the psoriasis.

Science.gov (United States)

Xu, Longjiang; Leng, Hong; Shi, Xin; Ji, Jiang; Fu, Jinxiang; Leng, Hong

2017-06-01

MicroRNAs (miRNAs) have been demonstrated to contribute to malignant progression in psoriasis development. The purposes of the study was to evaluated the effects of miRNA-155 on cell proliferation, migration and apoptosis in psoriasis development via PTEN singaling pathway and identify its direct target protein. Quantitative real-time RT-PCR (qRT-PCR) was performed to examine the level of miR-155 in psoriasis cells, miR-155 was downregulated in a psoriasis cell line Hacat by transfected with small interfering RNA (siRNA), respectively. Cell survival was detected by the MTT assay and colony formation assay. Cell migration and invasion were measured via wound-healing assayand transwell assay. In addition, cell cycle and apoptosis about psoriasis cells was measured by flow cytometry. In this study, qRT-PCR assay showed that the expressions of miR-155 mRNA in psoriasis tissues were significantly higher than that in normal tissues. The assays about cell growth and proliferation showed that miR-155 knockdown led to a significant decrease in cell proliferation which was determined by MTT assay and colony formation assay compared to those of Lv-NC cells. Flow cytometry analysis showed that depletion of miR-155 could cause cell cycle change and the number of apoptotic cells was significantly increased in Lv-miR155 cells compared with control cells. In addition, the expression of several apoptosis-related factors were dramatically changed, such as PTEN, PIP 3 , AKT, p-AKT, Bax and Bcl-2. Our findings indicate that down-regulation of miR-155 significantly inhibits proliferation, migration, invasion and promotes apoptosis through PTEN singaling pathway in psoriasis cells. miR-155 might function as an oncogene miRNA in the progress of psoriasis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Influence of impurities and ion surface alloying on the corrosion resistance of E110 alloy

International Nuclear Information System (INIS)

Kalin, B. A.; Volkov, N. V.; Valikov, R. A.; Novikov, V. V.; Markelov, V. A.; Pimenov, Yu. V.

2013-01-01

The corrosion resistance of zirconium alloys depends on their structural-phase state, the type of core coolant and operating factors. The formation of a protective oxide film on the zirconium alloys is sensitive to the content of impurity atoms present in the charge base of alloys and accumulating in them in the manufacture of products. The impurity composition of the initial zirconium is determined by the method of its manufacture and generally remains unchanged in the products, deter-mining their properties, including their corrosion resistance. An increased content of impurities (C, N, Al, Mo, Fe) both individually and in their combination negatively affects the corrosion resistance of zirconium and its alloys. One of the potentially effective methods to increase the protective properties of oxide films on zirconium alloys is a surface alloying using the regime of mixing the atoms of a film, preliminarily coated on the surface, and the atoms of a target. This method makes it possible to form a given structural-phase state in the thin surface layer with unique physicochemical properties and thus to in-crease the corrosion resistance and wear resistance of fuel claddings. In this context, the object of investigation was samples of cladding tubes from alloy E110 with various content of impurity elements (nitrogen, aluminum, and carbon) with the aim to reduce the negative influence of impurities on the corrosion resistance by changing the structural-phase state of the surface layer of fuel claddings and fuel assembly components with alloying in the regime of ion mixing of atoms

The role of microRNA-155/liver X receptor pathway in experimental and idiopathic pulmonary fibrosis.

Science.gov (United States)

Kurowska-Stolarska, Mariola; Hasoo, Manhl K; Welsh, David J; Stewart, Lynn; McIntyre, Donna; Morton, Brian E; Johnstone, Steven; Miller, Ashley M; Asquith, Darren L; Millar, Neal L; Millar, Ann B; Feghali-Bostwick, Carol A; Hirani, Nikhil; Crick, Peter J; Wang, Yuqin; Griffiths, William J; McInnes, Iain B; McSharry, Charles

2017-06-01

Idiopathic pulmonary fibrosis (IPF) is progressive and rapidly fatal. Improved understanding of pathogenesis is required to prosper novel therapeutics. Epigenetic changes contribute to IPF; therefore, microRNAs may reveal novel pathogenic pathways. We sought to determine the regulatory role of microRNA (miR)-155 in the profibrotic function of murine lung macrophages and fibroblasts, IPF lung fibroblasts, and its contribution to experimental pulmonary fibrosis. Bleomycin-induced lung fibrosis in wild-type and miR-155 -/- mice was analyzed by histology, collagen, and profibrotic gene expression. Mechanisms were identified by in silico and molecular approaches and validated in mouse lung fibroblasts and macrophages, and in IPF lung fibroblasts, using loss-and-gain of function assays, and in vivo using specific inhibitors. miR-155 -/- mice developed exacerbated lung fibrosis, increased collagen deposition, collagen 1 and 3 mRNA expression, TGF-β production, and activation of alternatively activated macrophages, contributed by deregulation of the miR-155 target gene the liver X receptor (LXR)α in lung fibroblasts and macrophages. Inhibition of LXRα in experimental lung fibrosis and in IPF lung fibroblasts reduced the exacerbated fibrotic response. Similarly, enforced expression of miR-155 reduced the profibrotic phenotype of IPF and miR-155 -/- fibroblasts. We describe herein a molecular pathway comprising miR-155 and its epigenetic LXRα target that when deregulated enables pathogenic pulmonary fibrosis. Manipulation of the miR-155/LXR pathway may have therapeutic potential for IPF. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Creep of titanium--silicon alloys

International Nuclear Information System (INIS)

Paton, N.E.; Mahoney, M.W.

1976-01-01

Operative creep mechanisms in laboratory melts of Ti-5Zr-0.5Si and Ti-5Zr-0.5Si have been investigated as a function of microstructure, creep stress, and temperature. From creep rate data and transmission electron microscopy results, it has been shown that an important creep strengthening mechanism at 811 0 K in Si-bearing Ti alloys is clustering of solute atoms on dislocations. All of the alloys investigated showed anomalously high apparent activation energies and areas for creep and a high exponent (n) in the Dorn equation. In addition, the effect of heat treatment was investigated and it is shown that the highest creep strength was obtained by using a heat treatment which retained the maximum amount of silicon in solution. This is consistent with the proposed creep strengthening mechanism. An investigation of the creep behavior of several other Si containing alloys including two commercial alloys, Ti-11 and IMI-685 indicated similar results. 12 fig., 6 tables

Deviations from Vegard’s law in ternary III-V alloys

KAUST Repository

Murphy, S. T.

2010-08-03

Vegard’s law states that, at a constant temperature, the volume of an alloy can be determined from a linear interpolation of its constituent’s volumes. Deviations from this description occur such that volumes are both greater and smaller than the linear relationship would predict. Here we use special quasirandom structures and density functional theory to investigate such deviations for MxN1−xAs ternary alloys, where M and N are group III species (B, Al, Ga, and In). Our simulations predict a tendency, with the exception of AlxGa1−xAs, for the volume of the ternary alloys to be smaller than that determined from the linear interpolation of the volumes of the MAs and BAs binary alloys. Importantly, we establish a simple relationship linking the relative size of the group III atoms in the alloy and the predicted magnitude of the deviation from Vegard’s law.

40 CFR 300.155 - Public information and community relations.

Science.gov (United States)

2010-07-01

... POLLUTION CONTINGENCY PLAN Responsibility and Organization for Response § 300.155 Public information and community relations. (a) When an incident occurs, it is imperative to give the public prompt, accurate...

Research on Zr50Al15-xNi10Cu25Yx amorphous alloys prepared by mechanical alloying with commercial pure element powders

International Nuclear Information System (INIS)

Long Woyun; Ouyang Xueqiong; Luo Zhiwei; Li Jing; Lu Anxian

2011-01-01

Amorphous Zr 50 Al 15-x Ni 10 Cu 25 Y x alloy powders were fabricated by mechanical alloying at low vacuum with commercial pure element powders. The effects on glass forming ability of Al partial substituted by Y in Zr 50 Al 15 Ni 10 Cu 25 and thermal stability of Si 3 N 4 powders addition were investigated. The as-milled powders were characterized by X-ray diffraction, scanning electron microscopy and differential scanning calorimeter. The results show that partial substitution of Al can improve the glass forming ability of Zr 50 Al 15 Ni 10 Cu 25 alloy. Minor Si 3 N 4 additions raise the crystallization activation energy of the amorphous phase and thus improve its thermal stability. -- Research Highlights: → ZrAlNiCu amorphous alloys can be synthesized by MA in low cost. → Appropriate amount of Al substituted by Y in ZrAlNiCu alloy can improve its glass forming ability. → A second phase particle addition helps to improve the thermal stability of the amorphous matrix.

MiR-155 is upregulated in patients with active tuberculosis and inhibits apoptosis of monocytes by targeting FOXO3.

Science.gov (United States)

Huang, Jian; Jiao, Junhua; Xu, Weihua; Zhao, Huayang; Zhang, Chunxiao; Shi, Yan; Xiao, Zhijian

2015-11-01

The aim of the present study was to investigate the association between microRNA (miR)-155 and apoptosis of monocytes infected by Mycobacterium tuberculosis, to examine the effect of forkhead box O3 (FOXO3) on miR‑155. The present study analysed the apoptosis of CD14+ in the peripheral blood of patients with active tuberculosis, disposed the THP‑1 human monocytic cell line by BCG and examined the expression of miR‑155. Furthermore, the expression of FOXO3 in THP‑1 cells was determined, and wild- and mutant-type luciferase reporter plasmids containing FOXO3 3'‑untranslated regions (UTRs) were constructed to analyse the expression of luciferase. Finally, an over‑expression plasmid was constructed, and THP-1 cells were transfected with control miRNA, miR‑155 and the plasmid, which revealed that miR‑155 inhibited the apoptosis of THP‑1 cells. miR‑155 in the THP‑1 cells infected by BCG was upregulated and apoptosis also increased. However, the apoptosis declined when the cells were transfected with the control miRNA and miR‑155. Folllowing transfection with miR‑155, the expression of FOXO3 decreased. Transfection with miR‑155 and the FOXO3 3'-UTRs significantly reduced luciferase, and overexpression of FOXO3 reversed the inhibitory role of miR‑155. From these results, it was concluded that mycobacteria can improve the level of miR‑155, while BCG can induce apoptosis in THP‑1 cells. The results suggested FOXO3 is a downstream target gene of miR‑155, which combines 3'-UTRs to inhibit the expression of FOXO3.

Rapamycin enhances the anti-angiogenesis and anti-proliferation ability of YM155 in oral squamous cell carcinoma.

Science.gov (United States)

Li, Kong-Liang; Wang, Yu-Fan; Qin, Jia-Ruo; Wang, Feng; Yang, Yong-Tao; Zheng, Li-Wu; Li, Ming-Hua; Kong, Jie; Zhang, Wei; Yang, Hong-Yu

2017-06-01

YM155, a small molecule inhibitor of survivin, has been studied in many tumors. It has been shown that YM155 inhibited oral squamous cell carcinoma through promoting apoptosis and autophagy and inhibiting proliferation. It was found that YM155 also inhibited the oral squamous cell carcinoma-mediated angiogenesis through the inactivation of the mammalian target of rapamycin pathway. Rapamycin, a mammalian target of rapamycin inhibitor, played an important role in the proliferation and angiogenesis of oral squamous cell carcinoma cell lines. In our study, cell proliferation assay, transwell assay, tube formation assay, and western blot assay were used to investigate the synergistic effect of rapamycin on YM155 in oral squamous cell carcinoma. Either in vitro or in vivo, rapamycin and YM155 exerted a synergistic effect on the inhibition of survivin and vascular endothelial growth factor through mammalian target of rapamycin pathway. Overall, our results revealed that low-dose rapamycin strongly promoted the sensitivity of oral squamous cell carcinoma cell lines to YM155.

Self-healing Li-Al layered double hydroxide conversion coating modified with aspartic acid for 6N01 Al alloy

International Nuclear Information System (INIS)

Zhang, Caixia; Luo, Xiaohu; Pan, Xinyu; Liao, Liying; Wu, Xiaosong; Liu, Yali

2017-01-01

Highlights: • A self-healing chrome-free Li-Al layered double hydroxide conversion coating modified with Aspartic acid was prepared. • One-step conversion coating formed by simple immersion in a conversion solution for a short time and a low temperature. • The conversion coating had excellent corrosion resistance. • The possible mechanism via exchange/self-assembly of the conversion coating was proposed in this paper. - Abstract: A self-healing Li-Al layered double hydroxide conversion coating (LCC) modified with aspartic acid (ALCC) was prepared on 6N01 Al alloy for corrosion protection. Scanning electron microscopy (SEM) showed that a compact thin film has been successfully formed on the alloy. X-ray diffraction (XRD) and FT-IR spectra proved that species of aspartic acid anions were successfully intercalated into LCC. Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and neutral salt spray (NSS) testing showed that the resultant ALCC could provide effective corrosion protection for the Al alloy. During immersion of the ALCC-coated alloy in 3.5% NaCl solution, new film was formed in the area of artificially introduced scratch, indicating its self-healing capability. XPS results demonstrated that Cl- anions exchange partial Asp anions according to the change content of element on conversion coating. From the above results, the possible mechanism via exchange/self-assembly was proposed to illustrate the phenomenon of self-healing.

Self-healing Li-Al layered double hydroxide conversion coating modified with aspartic acid for 6N01 Al alloy

Energy Technology Data Exchange (ETDEWEB)

Zhang, Caixia; Luo, Xiaohu; Pan, Xinyu; Liao, Liying; Wu, Xiaosong; Liu, Yali, E-mail: yaliliu@hnu.edu.cn

2017-02-01

Highlights: • A self-healing chrome-free Li-Al layered double hydroxide conversion coating modified with Aspartic acid was prepared. • One-step conversion coating formed by simple immersion in a conversion solution for a short time and a low temperature. • The conversion coating had excellent corrosion resistance. • The possible mechanism via exchange/self-assembly of the conversion coating was proposed in this paper. - Abstract: A self-healing Li-Al layered double hydroxide conversion coating (LCC) modified with aspartic acid (ALCC) was prepared on 6N01 Al alloy for corrosion protection. Scanning electron microscopy (SEM) showed that a compact thin film has been successfully formed on the alloy. X-ray diffraction (XRD) and FT-IR spectra proved that species of aspartic acid anions were successfully intercalated into LCC. Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and neutral salt spray (NSS) testing showed that the resultant ALCC could provide effective corrosion protection for the Al alloy. During immersion of the ALCC-coated alloy in 3.5% NaCl solution, new film was formed in the area of artificially introduced scratch, indicating its self-healing capability. XPS results demonstrated that Cl- anions exchange partial Asp anions according to the change content of element on conversion coating. From the above results, the possible mechanism via exchange/self-assembly was proposed to illustrate the phenomenon of self-healing.

33 CFR 334.155 - Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area.

Science.gov (United States)

2010-07-01

... Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area. 334.155 Section 334.155 Navigation and... RESTRICTED AREA REGULATIONS § 334.155 Severn River, Naval Station Annapolis, Small Boat Basin, Annapolis, MD; naval restricted area. (a) The area. The waters within the Naval Station Annapolis small boat basin and...

Theory of Anion-Substituted Nitrogen-Bearing III-V Alloys

Science.gov (United States)

1998-07-20

was found by Zunger group). When more than 4% arsenic is incorporated into GaN in an ordered array, the band gap closes . Calculations of the...arsenic is incorporated into GaN in an ordered array, the band gap closes . Calculations of the properties of random alloys predict smaller bowing...BEARING lll-V ALLOYS Prepared by: M. A. Berding, Senior Research Physicist M. van Schilfgaarde, Senior Research Physicist A. Sher, Associate Director

Investigations of the Optical Properties of GaNAs Alloys by First-Principle.

Science.gov (United States)

Borovac, Damir; Tan, Chee-Keong; Tansu, Nelson

2017-12-11

We present a Density Functional Theory (DFT) analysis of the optical properties of dilute-As GaN 1-x As x alloys with arsenic (As) content ranging from 0% up to 12.5%. The real and imaginary parts of the dielectric function are investigated, and the results are compared to experimental and theoretical values for GaN. The analysis extends to present the complex refractive index and the normal-incidence reflectivity. The refractive index difference between GaN and GaNAs alloys can be engineered to be up to ~0.35 in the visible regime by inserting relatively low amounts of As-content into the GaN system. Thus, the analysis elucidates on the birefringence of the dilute-As GaNAs alloys and comparison to other experimentally characterized III-nitride systems is drawn. Our findings indicate the potential of GaNAs alloys for III-nitride based waveguide and photonic circuit design applications.

Development of Al-Mg-Li alloys for fusion reactor

International Nuclear Information System (INIS)

Shoji, Yoshifusa; Yoshida, Hideo; Uno, Teruo; Baba, Yoshio; Kamada, Koji.

1985-01-01

Aluminum-magnesium-lithium alloys featuring low residual induced radioactivity and high electrical resistivity have been developed for fusion reactor structural materials. The addition of lithium in aluminum and Al-Mg alloys markedly increases electrical resistivity and tensile strength of them. However the elongation of Al-Mg-Li alloys containing more than 2 mass% lithium are less than 10 %. The Al-4--5 mass%Mg-1 mass%Li alloys are optimum for fusion reactor materials, and exhibit high resistivity (86 nΩm: 20 %IACS), medium strength (300 MPa) and good formability (22 % elongation). The variation of electrical resistivity of Al-Li and Al-Mg-Li alloys in solid solution can be approximated by the Matthiessen's rule. (author)

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

International Nuclear Information System (INIS)

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

2001-01-01

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

Ultrahigh-Speed Electrically Injected 1.55 micrometer Quantum Dot Microtube and Nanowire Lasers on Si

Science.gov (United States)

2015-08-30

and Al-rich AlGaN alloys have attracted significant attention for deep ultraviolet (DUV) optoelectronic devices, including light emitting diodes...growth orientation," Applied Physics Letters, vol. 96, p. 221110, 2010. [19] Y. Taniyasu, M. Kasu, and T. Makimoto, "An aluminium nitride light

Déficit cognitivo de la indefensión aprendida: Una aplicación de la detección de señales

OpenAIRE

Rodríguez García, Juan A.; Arnau Gras, Jaume

2012-01-01

Este estudio, trató de examinar la naturaleza del elemento cognitivo de la Indefensión Aprendida. En recientes trabajos (Alloy and Abramson, 1980; Ahramson, Alloy and Rosoff, 1981; Alloy and Seligman, 1979), se sugiere que el lugar del efecto de indefensión se encuentra en distorsiones del mecanismo expectacional involucrado en analizar contingencias de respuesta-consecuencia. En contraste, existen otras posturas alternativas que consideran que el efecto dv indefensión es debido a una falta d...

Effect of alloying elements on σ phase formation in Fe-Cr-Mn alloys

International Nuclear Information System (INIS)

Okazaki, Yoshimitsu; Miyahara, Kazuya; Hosoi, Yuzo; Tanino, Mitsuru; Komatsu, Hazime.

1989-01-01

Alloys of Fe-(8∼12%) Cr-(5∼30%) Mn were solution-treated at 1373 K for 3.6 ks, followed by cold-working of 50% reduction. Both solution-treated and 50% cold-worked materials were aged in the temperature range from 773 to 973 K for 3.6 x 10 3 ks. The identification of σ phase formation was made by using X-ray diffraction from the electrolytically extracted residues of the aged specimens. The region of σ phase formation determined by the present work is wider than that on the phase diagram already reported. It is to be noted that Mn promotes markedly the σ phase formation, and that three different types of σ phase formation are observed depending on Mn content: α→γ + α→γ + α + σ in 10% Mn, α→γ + σ in 15 to 20% Mn alloys, α→χ(Chi) →χ + σ + γ in 25 to 30% Mn alloys. An average electron concentration (e/a) in the σ phase was estimated by quantitative analysis of alloying elements using EPMA. The e/a value in the σ phase formed in Fe-(12∼16%) Cr-Mn alloys aged at 873 K for 3.6 x 10 3 ks is about 7.3, which is independent of Mn content. In order to prevent σ phase formation in Fe-12% Cr-15% Mn alloy, the value of Ni * eq of 11 (Ni * eq = Ni + 30(C) + 25(N)) is required. (author)

38 CFR 17.155 - Minimum standards of safety and quality for automotive adaptive equipment.

Science.gov (United States)

2010-07-01

... safety and quality for automotive adaptive equipment. 17.155 Section 17.155 Pensions, Bonuses, and... Minimum standards of safety and quality for automotive adaptive equipment. (a) The Under Secretary for... officials that it meets implicit standards of safety and quality adopted by the industry or as later...

Inhibited Aluminization of an ODS FeCr Alloy

International Nuclear Information System (INIS)

Vande Put Ep Rouaix, Aurelie; Pint, Bruce A.

2012-01-01

Aluminide coatings are of interest for fusion energy applications both for compatibility with liquid Pb-Li and to form an alumina layer that acts as a tritium permeation barrier. Oxide dispersion strengthened (ODS) ferritic steels are a structural material candidate for commercial reactor concepts expected to operate above 600 C. Aluminizing was conducted in a laboratory scale chemical vapor deposition reactor using accepted conditions for coating Fe- and Ni-base alloys. However, the measured mass gains on the current batch of ODS Fe-14Cr were extremely low compared to other conventional and ODS alloys. After aluminizing at two different Al activities at 900 C and at 1100 C, characterization showed that the ODS Fe-14Cr specimens formed a dense, primarily AlN layer that prevented Al uptake. This alloy batch contained a higher (> 5000 ppma) N content than the other alloys coated and this is the most likely reason for the inhibited aluminization. Other factors such as the high O content, small (∼ 140 nm) grain size and Y-Ti oxide nano-clusters in ODS Fe-14Cr also could have contributed to the observed behavior. Examples of typical aluminide coatings formed on conventional and ODS Fe- and Ni-base alloys are shown for comparison.

N-cadherin{sup +} HSCs in fetal liver exhibit higher long-term bone marrow reconstitution activity than N-cadherin{sup -} HSCs

Energy Technology Data Exchange (ETDEWEB)

Toyama, Hirofumi; Arai, Fumio; Hosokawa, Kentaro; Ikushima, Yoshiko Matsumoto [Department of Cell Differentiation, The Sakaguchi Laboratory of Developmental Biology, School of Medicine, Keio University, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Suda, Toshio, E-mail: sudato@z3.keio.jp [Department of Cell Differentiation, The Sakaguchi Laboratory of Developmental Biology, School of Medicine, Keio University, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan)

2012-11-23

Highlights: Black-Right-Pointing-Pointer High N-cad expression was detected in E12.5 mouse FL LT-HSCs (EPCR{sup +} LSK cells). Black-Right-Pointing-Pointer Immunohistochemically, N-cad{sup +} HSCs co-localized with sinusoidal ECs (Lyve-1{sup +} cells) in E12.5 FL, but these gradually detached in E15.5 and E18.5 FL. Black-Right-Pointing-Pointer N-cad{sup +} LSK cells in E12.5 FL exhibited higher LTR activity versus N-cad{sup -} LSK cells, which decreased in E15.5 and E18.5. Black-Right-Pointing-Pointer N-cad expression may confer high LTR activity to HSCs by facilitating interactions with the perisinusoidal niche in FL. -- Abstract: Adult hematopoietic stem cells (HSCs) are maintained in a microenvironment known as the stem cell niche. The regulation of HSCs in fetal liver (FL) and their niche, however, remains to be elucidated. In this study, we investigated the role of N-cadherin (N-cad) in the maintenance of HSCs during FL hematopoiesis. By using anti-N-cad antibodies (Abs) produced by our laboratory, we detected high N-cad expression in embryonic day 12.5 (E12.5) mouse FL HSCs, but not in E15.5 and E18.5 FL. Immunofluorescence staining revealed that N-cad{sup +}c-Kit{sup +} and N-cad{sup +} endothelial protein C receptor (EPCR){sup +} HSCs co-localized with Lyve-1{sup +} sinusoidal endothelial cells (ECs) in E12.5 FL and that some of these cells also expressed N-cad. However, N-cad{sup +} HSCs were also observed to detach from the perisinusoidal niche at E15.5 and E18.5, concomitant with a down-regulation of N-cad and an up-regulation of E-cadherin (E-cad) in hepatic cells. Moreover, EPCR{sup +} long-term (LT)-HSCs were enriched in the N-cad{sup +}Lin{sup -}Sca-1{sup +}c-Kit{sup +} (LSK) fraction in E12.5 FL, but not in E15.5 or E18.5 FL. In a long-term reconstitution (LTR) activity assay, higher engraftment associated with N-cad{sup +} LSK cells versus N-cad{sup -} LSK cells in E12.5 FL when transplanted into lethally irradiated recipient mice. However, the

The effects of Mg addition on the microstructure and mechanical properties of thixoformed Al–5%Si–Cu alloys

International Nuclear Information System (INIS)

Salleh, M.S.; Omar, M.Z.; Syarif, J.

2015-01-01

Highlights: • The average globule size of α-Al decreased when Mg amount is increased. • T6 heat treatment has increased the strength of the thixoformed alloys. • The elongation after T6 heat treatment is even significantly improved. • Thixoformed alloy with high Mg content shows a brittle type fracture. • Thixoformed alloy in T6 condition shows a ductile type fracture. - Abstract: In this study, the effects of different amounts of magnesium (Mg) on the microstructures and tensile properties of thixoformed Al–5%Si–Cu alloys were investigated. Three different alloys containing various amounts of Mg (0.5, 0.8 and 1.2 wt%) were prepared through the cooling slope casting technique, before they were thixoformed using a compression press. Several of the thixoformed samples were then treated with a T6 heat treatment, that is, solution treatment at 525 °C for 8 h, quenching in warm water at 60 °C, followed by aging at 155 °C for 4 h. All of the samples were then characterised by optical microscopy (OM), scanning electron microscopy (SEM) energy dispersive X-ray (EDX) spectroscopy and X-ray diffraction (XRD) analysis as well as by tensile tests. The results revealed that magnesium was able to refine the size of α-Al globules and the eutectic silicon in the samples. It was also observed that a compact π-Al 9 FeMg 3 Si 5 phase was formed when the magnesium content was 0.8 wt% and 1.2 wt%. The mechanical properties of the thixoformed alloys improved significantly after the T6 heat treatment. The highest attainment was recorded by the latter alloy (i.e. with 1.2 wt%Mg) with its ultimate tensile strength (UTS) as high as 306 MPa, yield strength (YS), 264 MPa, and elongation to fracture of 1.8%. The fracture of thixoformed alloy with a low Mg content (0.5 wt%) showed a combination of dimple and cleavage fracture, whereas in the alloy that contained the highest Mg content (1.2 wt%), cleavage fracture was observed

MicroRNA-155 Deficiency Attenuates Liver Steatosis and Fibrosis without Reducing Inflammation in a Mouse Model of Steatohepatitis.

Directory of Open Access Journals (Sweden)

Timea Csak

Full Text Available MicroRNAs (miRs regulate hepatic steatosis, inflammation and fibrosis. Fibrosis is the consequence of chronic tissue damage and inflammation. We hypothesized that deficiency of miR-155, a master regulator of inflammation, attenuates steatohepatitis and fibrosis.Wild type (WT and miR-155-deficient (KO mice were fed methionine-choline-deficient (MCD or -supplemented (MCS control diet for 5 weeks. Liver injury, inflammation, steatosis and fibrosis were assessed.MCD diet resulted in steatohepatitis and increased miR-155 expression in total liver, hepatocytes and Kupffer cells. Steatosis and expression of genes involved in fatty acid metabolism were attenuated in miR-155 KO mice after MCD feeding. In contrast, miR-155 deficiency failed to attenuate inflammatory cell infiltration, nuclear factor κ beta (NF-κB activation and enhanced the expression of the pro-inflammatory cytokines tumor necrosis factor alpha (TNFα and monocyte chemoattractant protein-1 (MCP1 in MCD diet-fed mice. We found a significant attenuation of apoptosis (cleaved caspase-3 and reduction in collagen and α smooth muscle actin (αSMA levels in miR-155 KO mice compared to WTs on MCD diet. In addition, we found attenuation of platelet derived growth factor (PDGF, a pro-fibrotic cytokine; SMAD family member 3 (Smad3, a protein involved in transforming growth factor-β (TGFβ signal transduction and vimentin, a mesenchymal marker and indirect indicator of epithelial-to-mesenchymal transition (EMT in miR-155 KO mice. Nuclear binding of CCAAT enhancer binding protein β (C/EBPβ a miR-155 target involved in EMT was significantly increased in miR-155 KO compared to WT mice.Our novel data demonstrate that miR-155 deficiency can reduce steatosis and fibrosis without decreasing inflammation in steatohepatitis.

Grindability of cast Ti-Cu alloys.

Science.gov (United States)

Kikuchi, Masafumi; Takada, Yukyo; Kiyosue, Seigo; Yoda, Masanobu; Woldu, Margaret; Cai, Zhuo; Okuno, Osamu; Okabe, Toru

2003-07-01

The purpose of the present study was to evaluate the grindability of a series of cast Ti-Cu alloys in order to develop a titanium alloy with better grindability than commercially pure titanium (CP Ti), which is considered to be one of the most difficult metals to machine. Experimental Ti-Cu alloys (0.5, 1.0, 2.0, 5.0, and 10.0 mass% Cu) were made in an argon-arc melting furnace. Each alloy was cast into a magnesia mold using a centrifugal casting machine. Cast alloy slabs (3.5 mm x 8.5 mm x 30.5 mm), from which the hardened surface layer (250 microm) was removed, were ground using a SiC abrasive wheel on an electric handpiece at four circumferential speeds (500, 750, 1000, or 1250 m/min) at 0.98 N (100 gf). Grindability was evaluated by measuring the amount of metal volume removed after grinding for 1min. Data were compared to those for CP Ti and Ti-6Al-4V. For all speeds, Ti-10% Cu alloy exhibited the highest grindability. For the Ti-Cu alloys with a Cu content of 2% or less, the highest grindability corresponded to an intermediate speed. It was observed that the grindability increased with an increase in the Cu concentration compared to CP Ti, particularly for the 5 or 10% Cu alloys at a circumferential speed of 1000 m/min or above. By alloying with copper, the cast titanium exhibited better grindability at high speed. The continuous precipitation of Ti(2)Cu among the alpha-matrix grains made this material less ductile and facilitated more effective grinding because small broken segments more readily formed.

33 CFR 155.4032 - Other resource provider considerations.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Other resource provider... Salvage and Marine Firefighting § 155.4032 Other resource provider considerations. (a) Use of resource providers not listed in the VRP. If another resource provider, not listed in the approved plan for the...

Surface of Ti-Ni alloys after their preparation

International Nuclear Information System (INIS)

Saldan, I.; Frenzel, J.; Shekhah, O.; Chelmowski, R.; Birkner, A.; Woell, Ch.

2009-01-01

The Ti 3.87 Ni 1.73 Fe 0.7 O 0.3, Ti 3.87 Ni 1.73 Fe 0.4 N 0.3 and Ti 3.87 Ni 1.73 Fe 0.4 C 0.3 alloys were investigated regarding their surface characteristics. The scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) was used for phase characterization. The X-ray photoelectron spectroscopy (XPS) was used to analyze the chemical composition of alloy surface. The atomic force microscopy (AFM) to observe alloy surface topography after cutting and electrochemical polishing separately has been done. The transmission electron microscopy (TEM) with X-ray diffraction was carried out to get a high contrast images and the diffraction pattern from alloy surface. The results clearly shown, that all alloys were multiphase, and their surface was totally oxidized with no pure metals

Magnesium secondary alloys: Alloy design for magnesium alloys with improved tolerance limits against impurities

Energy Technology Data Exchange (ETDEWEB)

Blawert, C., E-mail: carsten.blawert@gkss.d [GKSS Forschungszentrum Geesthacht GmbH, Max-Planck-Str. 1, 21502 Geesthacht (Germany); Fechner, D.; Hoeche, D.; Heitmann, V.; Dietzel, W.; Kainer, K.U. [GKSS Forschungszentrum Geesthacht GmbH, Max-Planck-Str. 1, 21502 Geesthacht (Germany); Zivanovic, P.; Scharf, C.; Ditze, A.; Groebner, J.; Schmid-Fetzer, R. [TU Clausthal, Institut fuer Metallurgie, Robert-Koch-Str. 42, 38678 Clausthal-Zellerfeld (Germany)

2010-07-15

The development of secondary magnesium alloys requires a completely different concept compared with standard alloys which obtain their corrosion resistance by reducing the levels of impurities below certain alloy and process depending limits. The present approach suitable for Mg-Al based cast and wrought alloys uses a new concept replacing the {beta}-phase by {tau}-phase, which is able to incorporate more impurities while being electro-chemically less detrimental to the matrix. The overall experimental effort correlating composition, microstructure and corrosion resistance was reduced by using thermodynamic calculations to optimise the alloy composition. The outcome is a new, more impurity tolerant alloy class with a composition between the standard AZ and ZC systems having sufficient ductility and corrosion properties comparable to the high purity standard alloys.

Corrosion Behavior of High Pressure Die Cast Al-Ni and Al-Ni-Ca Alloys in 3.5% NaCl Solution

Energy Technology Data Exchange (ETDEWEB)

Arthanari, Srinivasan; Jang, Jae Cheol; Shin, Kwang Seon [Seoul National University, Seoul (Korea, Republic of)

2017-06-15

In this investigation corrosion behavior of newly developed high-pressure die cast Al-Ni (N15) and Al-Ni-Ca (NX1503) alloys was studied in 3.5% NaCl solution. The electrochemical corrosion behavior was evaluated using open circuit potential (OCP) measurement, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) techniques. Potentiodynamic polarization results validated that NX1503 alloy exhibited lower corrosion current density (i{sub corr}) value (5.969 μA/cm{sup 2}) compared to N15 (7.387 μA/cm{sup 2}). EIS-Bode plots revealed a higher impedance (|Z|) value and maximum phase angle value for NX1503 than N15 alloy. Equivalent circuit curve fitting analysis revealed that surface layer (R{sub 1}) and charge transfer resistance (R{sub ct}) values of NX1503 alloy was higher compared to N15 alloy. Immersion corrosion studies were also conducted for alloys using fishing line specimen arrangement to simultaneously measure corrosion rates from weight loss (P{sub W}) and hydrogen volume (P{sub H}) after 72 hours and NX1503 alloy had lower corrosion rate compared to N15 alloy. The addition of Ca to N15 alloy significantly reduced the Al{sub 3}Ni intermetallic phase and further grain refinement may be attributed for reduction in the corrosion rate.

Is HERV-K and HERV-W expression regulated by mir-155 in Sézary syndrome?

Science.gov (United States)

Bergallo, Massimiliano; Daprà, Valentina; Novelli, Mauro; Rassu, Marco; Montanari, Paola; Galliano, Ilaria; Quaglino, Pietro; Fierro, Maria T

2018-03-26

According to the latest update, 2578 unique mature miRNAs are currently annotated in the human genome and participate in the regulation of multiple events, such as cellular proliferation or apoptosis. A previous study analyzing global miRNA expression patterns in GH cells (high HERV-K versus low) showed that two miRNAs (miR-663 and miR-638) are differentially regulated and exhibit expression parallel to that of HERV-K. The aim of this study was to evaluate HERV-K and -W pol gene and mir-155 expression in SS patients and possible relationship between them. The comparison between SS patients and healthy donor showed a significant difference in terms of mir-155 expression p=0.0003 as previously reported by our groups. We demonstrated that HERV-K and -W pol gene expression was significantly higher in SS patients vs healthy donor as previously reported by our groups. Our correlation data suggest that miR-155 are not directly involved in regulating the HERVs. Furthermore, further studies including other cohorts of pathology with mir-155 and HERVs involvement such as inflammatory diseases are needed to investigate the role of mir-155 in the cross-activations of HERVs.

Alloying principles for magnesium base heat resisting alloys

International Nuclear Information System (INIS)

Drits, M.E.; Rokhlin, L.L.; Oreshkina, A.A.; Nikitina, N.I.

1982-01-01

Some binary systems of magnesium-base alloys in which solid solutions are formed, are considered for prospecting heat resistant alloys. It is shown that elements having essential solubility in solid magnesium strongly decreasing with temperature should be used for alloying maqnesium base alloys with high strength properties at increased temperatures. The strengthening phases in these alloys should comprise essential quantity of magnesium and be rather refractory

Hard coatings on magnesium alloys by sputter deposition using a pulsed d.c. bias voltage

Energy Technology Data Exchange (ETDEWEB)

Reiners, G. [Bundesanstalt fuer Materialforschung und -pruefung, Berlin (Germany); Griepentrog, M. [Bundesanstalt fuer Materialforschung und -pruefung, Berlin (Germany)

1995-12-01

An increasing use of magnesium-based light-metal alloys for various industrial applications was predicted in different technological studies. Companies in different branches have developed machine parts made of magnesium alloys (e.g. cars, car engines, sewing and knitting machines). Hence, this work was started to evaluate the ability of hard coatings obtained by physical vapour deposition (PVD) in combination with coatings obtained by electrochemical deposition to protect magnesium alloys against wear and corrosion. TiN hard coatings were deposited onto magnesium alloys by unbalanced magnetron sputter deposition. A bipolar pulsed d.c. bias voltage was used to limit substrate temperatures to 180 C during deposition without considerable loss of microhardness and adhesion. Adhesion, hardness and load-carrying capacity of TiN coatings deposited directly onto magnesium alloys are compared with the corresponding values of TiN coatings deposited onto substrates which had been coated electroless with an Ni-P alloy interlayer prior to the PVD. (orig.)

Dry sliding wear behaviour of Al-12Si-4Mg alloy with cerium addition

International Nuclear Information System (INIS)

Anasyida, A.S.; Daud, A.R.; Ghazali, M.J.

2010-01-01

The purpose of this work is to understand the effect of cerium addition on wear resistance behaviour of as-cast alloys. Al-12Si-4 Mg alloys with 1-5 wt% cerium addition were prepared using the casting technique. A sliding wear test was carried out under applied loads of 10 N, 30 N and 50 N at a fixed sliding speed of 1 m/s using a pin-on-disc configuration. The wear test was conducted in dry conditions at room temperature of ∼25 o C. Detailed analysis of the microstructure, worn surface, collected debris and microhardness was undertaken in order to investigate the differences between the as-cast alloys with different levels of cerium addition. The addition of 1-5 wt% cerium was found to lead to the precipitation of intermetallic phases (Al-Ce), resulting a needle-like structures. Increasing cerium content up to 2 wt% improved both wear resistance and microhardness of as-cast alloys. Addition of more than 2 wt% cerium, however, led to a decrease in microhardness, resulting in lower wear resistance of the alloys. Moderate wear was observed at all loads, with specific wear rates (K') ranging from 6.82 x 10 -5 with 2 wt% Ce at applied load of 50 N to 21.48 x 10 -5 mm 3 /N m without added Ce at an applied load of 10 N. Based on K' ranges, the as-cast alloys exhibited moderate wear regimes, and the mechanism of wear is a combination of abrasion and adhesion. Alloy containing 2 wt% Ce, with the highest hardness and lowest K' value, showed the greatest wear resistance.

High mobility two-dimensional electron gases in nitride heterostructures with high Al composition AlGaN alloy barriers

International Nuclear Information System (INIS)

Li Guowang; Cao Yu; Xing Huili Grace; Jena, Debdeep

2010-01-01

We report high-electron mobility nitride heterostructures with >70% Al composition AlGaN alloy barriers grown by molecular beam epitaxy. Direct growth of such AlGaN layers on GaN resulted in hexagonal trenches and a low mobility polarization-induced charge. By applying growth interruption at the heterojunction, the surface morphology improved dramatically and the room temperature two-dimensional electron gas (2DEG) mobility increased by an order of magnitude, exceeding 1300 cm 2 /V s. The 2DEG density was tunable at 0.4-3.7x10 13 /cm 2 by varying the total barrier thickness (t). Surface barrier heights of the heterostructures were extracted and exhibited dependence on t.

Formation of nano sized ODS clusters in mechanically alloyed NiAl-(Y,Ti,O) alloys

International Nuclear Information System (INIS)

Kim, Yong Deog; Bae Seong Man; Wirth, Brian D.

2012-01-01

The Reactor Pressure Vessel (RPV) is the key component in determining the lifetime of nuclear power plants because it is subject to the significant aging degradation by irradiation and thermal aging, and there is no practical method for replacing that component. Advanced reactors with much larger capacity than current reactor require the usage of higher strength materials inevitably. The SA508 Gr.4N Ni-Cr-Mo low alloy steel, in which Ni and Cr contents are larger than in conventional RPV steels, could be a promising RPV material offering improved strength and toughness from its tempered martensitic microstructure. For a structural integrity of RPV, the effect of neutron irradiation on the material property is one of the key issues. The RPV materials suffer from the significant degradation of transition properties by the irradiation embrittlement when its strength is increased by a hardening mechanism. Therefore, the potential for application of SA508 Gr.4N steel as the structural components for nuclear power reactors depends on its ability to maintain adequate transition properties against the operating neutron does. However, it is not easy to fine the data on the irradiation effect on the mechanical properties of SA508 Gr.4N steel. In this study, the irradiation embrittlement of SA508 Gr.4N Ni-Cr-Mo low alloy steel was evaluated by using specimens irradiated in research reactor. For comparison, the variations of mechanical properties by neutron irradiation for commercial SA508 Gr.3 Mn-Mo-Ni low alloy steel were also evaluated

Ductility increase in difficult to work nickel alloys due to calcium microalloying

International Nuclear Information System (INIS)

Shevtsov, V.A.; Grigoryan, R.A.; Aleev, V.P.; Stepanov, V.P.; Bytskij, E.V.

1995-01-01

Impact of calcium microadditions on mechanical properties of heat-resisting alloys Kh66VMTYu and KhN33KV is studied. It is established that the calcium additions up to 0.01% essentially increase the alloy plastic characteristics of the alloy without changing its strength characteristics.5 refs., 3 figs

High Temperature Deformation of Twin-Roll Cast Al-Mn-Based Alloys after Equal Channel Angular Pressing.

Science.gov (United States)

Málek, Přemysl; Šlapáková Poková, Michaela; Cieslar, Miroslav

2015-11-12

Twin roll cast Al-Mn- and Al-Mn-Zr-based alloys were subjected to four passes of equal channel angular pressing. The resulting grain size of 400 nm contributes to a significant strengthening at room temperature. This microstructure is not fully stable at elevated temperatures and recrystallization and vast grain growth occur at temperatures between 350 and 450 °C. The onset of these microstructure changes depends on chemical and phase composition. Better stability is observed in the Al-Mn-Zr-based alloy. High temperature tensile tests reveal that equal channel angular pressing results in a softening of all studied materials at high temperatures. This can be explained by an active role of grain boundaries in the deformation process. The maximum values of ductility and strain rate sensitivity parameter m found in the Al-Mn-Zr-based alloy are below the bottom limit of superplasticity (155%, m = 0.25). However, some features typical for superplastic behavior were observed-the strain rate dependence of the parameter m , the strengthening with increasing grain size, and the fracture by diffuse necking. Grain boundary sliding is believed to contribute partially to the overall strain in specimens where the grain size remained in the microcrystalline range.

41 CFR 102-74.155 - What energy conservation policy must Federal agencies follow in the management of facilities?

Science.gov (United States)

2010-07-01

... policy must Federal agencies follow in the management of facilities? 102-74.155 Section 102-74.155 Public... MANAGEMENT REGULATION REAL PROPERTY 74-FACILITY MANAGEMENT Facility Management Energy Conservation § 102-74.155 What energy conservation policy must Federal agencies follow in the management of facilities...

Friction and wear behaviour of hypereutectic Al-Si alloy/steel tribopair under dry and lubricated conditions

Directory of Open Access Journals (Sweden)

Parveen Kumar

2017-12-01

Full Text Available Dry and lubricated sliding tribological tests on hypereutectic Al-25Si alloy was performed using a ball- on- disk configuration at room temperature. Hypereutectic Al-25Si alloy were prepared by rapid solidification process under T6 condition. Friction coefficient (COF and wear rate of the alloy were measured under different applied loads ranging from 5–100 N. It is found that the friction coefficient varies with load, first declines (from 5-50 N, then increases (from 50-80 N and then again decreases (80-100 N. The wear rate of the samples of hypereutectic Al-25Si alloy, first increases and then decreases with increasing the applied normal load. Hypereutectic Al-25Si alloy presents higher wear rate at 50 N due to the participation of a large amount of needle-like precipitates, but shows low wear rate under high load of 100 N because of the work hardening layer. Worn surface morphologies were analyzed using optical and scanning electron microscope (SEM coupled with an energy dispersive spectrometer (EDS. The improvements in COF and wear rate were mainly attributed to morphology, size and distribution of Si particles due to its fabrication process. The dominant wear mechanism for hypereutectic Al-25Si alloy was adhesive wear, abrasive wear and plastic deformation.

Effects of the phase fractions on the carbide morphologies, Charpy and tensile properties in SA508 Gr.4N High Strength Low Alloy RPV Steel

Energy Technology Data Exchange (ETDEWEB)

Park, Sang Gyu; Wee, Dang Moon [KAIST, Daejeon (Korea, Republic of); Kim, Min Chul; Lee, Bong Sang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2011-05-15

To improve the strength and toughness of RPV (reactor pressure vessel) steels for nuclear power plants, an effective way is the change of material specification from tempered bainitic SA508 Gr.3 Mn-Mo-Ni low alloy steel into tempered martensitic/bainitic SA508 Gr.4N Ni-Cr-Mo low alloy steel. It is known that the phase fractions of martensitic/bainitic steels are very sensitive to the austenitizing cooling rates. Kim reported that there are large differences of austenitizing cooling rates between the surface and the center locations in RPV due to its thickness of 250mm. Hence, the martensite/bainite fractions would be changed in different locations, and it would affect the microstructure and mechanical properties in Ni-Cr-Mo low alloy steel. These results may lead to inhomogeneous characteristics after austenitizing. Therefore, it is necessary to evaluate the changes of microstructure and mechanical properties with varying phase fractions in Ni-Cr-Mo low alloy steel. In this study, the effects of martensite/bainite fractions on microstructure and mechanical properties in Ni-Cr-Mo low alloy steel were examined. The changes in phase fractions of Ni-Cr-Mo low alloy steel with different cooling rates were analyzed, and then the phase fractions were correlated with its microstructural observation and mechanical properties

Effect of plasma molybdenized buffer layer on adhesive properties of TiN film coated on Ti6Al4V alloy

Energy Technology Data Exchange (ETDEWEB)

Qin, Lin, E-mail: qinlin@tyut.edu.cn; Yi, Hong; Kong, Fanyou; Ma, Hua; Guo, Lili; Tian, Linhai; Tang, Bin

2017-05-01

Highlights: • A molybdenized layer was prepared as a buffer layer under TiN film on Ti6Al4V. • The molybdenized layer can enhance adhesion strength of PVD coatings effectively. • The duplex treated samples increase elastic energy ratio in the impact tests. • The enhancement attributes to the hardness improvement and inverted-S shape elastic modulus profile of the modified layer. - Abstract: Effect of molybdenized buffer layer on adhesion strength of TiN film on Ti6Al4V alloy was investigated. The buffer layer composed of a dense molybdenum deposition layer, a rapid drop zone and a slow fall zone was prepared using double glow plasma surface alloying technique. Scratch tests and low energy repeated impact tests were adopted to comparatively evaluate the duplex treated layers and the single TiN samples. The results show that the critical load was increased from 62 N for the single TiN film to over 100 N for the duplex treated layer. The volume of impact pit, formed in impact tests, of the single TiN samples is 9.15 × 10{sup 6} μm{sup 3}, and about 1.5 times than that of the duplex treated samples. The Leeb hardness values reveal that about 70% impact energy was transferred to the single TiN samples to generate permanent deformation, while that was only about 47% for the duplex treated samples. The mechanism of improving adhesion strength is attributed to synergistic effect due to an inverted-S shape elastic modulus distribution produced by the molybdenized layer.

Alloy materials

Energy Technology Data Exchange (ETDEWEB)

Hans Thieme, Cornelis Leo (Westborough, MA); Thompson, Elliott D. (Coventry, RI); Fritzemeier, Leslie G. (Acton, MA); Cameron, Robert D. (Franklin, MA); Siegal, Edward J. (Malden, MA)

2002-01-01

An alloy that contains at least two metals and can be used as a substrate for a superconductor is disclosed. The alloy can contain an oxide former. The alloy can have a biaxial or cube texture. The substrate can be used in a multilayer superconductor, which can further include one or more buffer layers disposed between the substrate and the superconductor material. The alloys can be made a by process that involves first rolling the alloy then annealing the alloy. A relatively large volume percentage of the alloy can be formed of grains having a biaxial or cube texture.

30 CFR 75.155 - Qualified hoisting engineer; qualifications.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Qualified hoisting engineer; qualifications. 75... Persons § 75.155 Qualified hoisting engineer; qualifications. (a)(1) A person is a qualified hoisting engineer within the provisions of subpart O of this part, for the purpose of operating a steam-driven hoist...

Effect of elastic interphase strains on extinction in aging nimonic type alloys

International Nuclear Information System (INIS)

Gitgarts, M.I.; Ivashin, V.V.

1977-01-01

The effect of νsup(')-phase separation processes on the variation of (3) CuKsub(α) diffraction line integral intensity in KhN67VMTYu alloy ageing has been investigated, the alloy being characterized by various degrees of volumetric inconsistency between the separation phase and matrix. The ageing of KhN67VMTYu alloy, in which the separation of the νsup(')-phase does not cause interphase strains, is not accompanied by abatement of extinction: the diffraction line intensity is practically the same for both aged and tempered specimens

Growth of vertically aligned multiwalled carbon nanotubes forests on metal alloy Ni-Nb-N with low content of catalyst

Science.gov (United States)

Dubkov, S.; Trifonov, A.; Shaman, Yu; Pavlov, A.; Shulyat'ev, A.; Skorik, S.; Kirilenko, E. P.; Rygalin, B.

2016-08-01

This research shows the possibility of carbon nanotubes (CNTs) formation on the surface of low nickel (∼ 10 at.%) Ni-Nb-N amorphous metal alloy film by CVD method at 550 °C of the gas mixture based on acetylene. The structure of CNT were studied by transmission and scanning-electron microscopy, energy-dispersive X-ray and the Raman spectroscopy.

Stretch strength of Al-Li alloy sheet

Energy Technology Data Exchange (ETDEWEB)

Sato, K.; Sawa, Y.; Yokoyama, T.; Fujimoto, S. [Science Univ. of Tokyo (Japan). Dept. of Mech. Eng.; Sakamoto, T. [Kobe Steel Works, Tokyo (Japan)

1998-07-01

Stretch test on Al-Li alloy sheet was carried out in stretch rate of 0.01 to 0.2 mm/sec. The limiting stretch depth was measured in various conditions and the following results were obtained. (1) Stretch rate does not affect the limiting stretch depth of Al-Li alloy. (2) The limiting stretch depth is increased with increase of the profile radius. (3) Strain hardening exponent(n-value) and r-value of Lankford do not affect the limiting stretch depth. (4) Rapture pattern in stretch test of Al is {alpha} type rapture and that of Al-Li alloy is straight line type rapture. (orig.) 4 refs.

Current Status of Development of High Nickel Low Alloy Steels for Commercial Reactor Pressure Vessel

Energy Technology Data Exchange (ETDEWEB)

Kim, Min Chul; Lee, B. S.; Park, S. G.; Lee, K. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2008-12-15

SA508 Gr.3 Mn-Mo-Ni low alloy steels have been used for nuclear reactor pressure vessel steels up to now. Currently, the design goal of nuclear power plant is focusing at larger capacity and longer lifetime. Requirements of much bigger pressure vessels may cause critical problems in the manufacturing stage as well as for the welding stage. Application of higher strength steel may be required to overcome the technical problems. It is known that a higher strength and fracture toughness of low alloy steels such as SA508 Gr.4N low alloy steel could be achieved by increasing the Ni and Cr contents. Therefore, SA508 Gr.4N low alloy steel is very attractive as eligible RPV steel for the next generation PWR systems. In this report, we propose the possibility of SA508 Gr.4N low alloy steel for an application of next generation commercial RPV, based on the literature research result about development history of the RPV steels and SA508 specification. In addition, we have surveyed the research result of HSLA(High Strength Low Alloy steel), which has similar chemical compositions with SA508 Gr.4N, to understand the problems and the way of improvement of SA508 Gr.4N low alloy steel. And also, we have investigated eastern RPV steel(WWER-1000), which has higher Ni contents compared to western RPV steel.

Postirradiation notch ductility tests of ESR alloy HT-9 and modified 9Cr-1Mo alloy from UBR reactor experiments

International Nuclear Information System (INIS)

Hawthorne, J.R.

1984-01-01

During this period, irradiation exposures at 300 0 C and 150 0 C to approx. 8 x 10 19 n/cm 2 , E > 0.1 MeV, were completed for the Alloy HT-9 plate and the modified Alloy 9Cr-1Mo plates, respectively. Postirradiation tests of Charpy-V (C/sub v/) specimens were completed for both alloys; other specimen types included in the reactor assemblies were fatigue precracked Charpy-V (PCC/sub v/), half-size Charpy-V, and in the case of the modified 9Cr-1Mo, 2.54 mm thick compact tension specimens

Protective effects of geniposide and ginsenoside Rg1 combination treatment on rats following cerebral ischemia are mediated via microglial microRNA‑155‑5p inhibition.

Science.gov (United States)

Wang, Jun; Li, Dan; Hou, Jincai; Lei, Hongtao

2018-02-01

Geniposide, an active component of Gardenia, has been reported to protect against cerebral ischemia in animals. Ginsenoside Rg1, a component of Panax notoginseng, is usually administered in combination with Gardenia for the treatment of acute ischemic stroke; however, there are unknown effects of ginsenoside Rg1 that require further investigation. In the present study, the effects of geniposide and ginsensoide Rg1 combination treatment on focal cerebral ischemic stroke were investigated. For in vivo analysis, male rats were separated into three groups, including the (control), model and geniposide + ginsenoside Rg1 groups (n=8 per group). A middle cerebral artery occlusion model was established as the model group. The treatment group was treated with geniposide (30 mg/kg, tail vein injection) + ginsenoside Rg1 (6 mg/kg, tail vein injection), and the model group received saline instead. Neurobehavioral deficits, infarct volume, brain edema, and the expression of microRNA (miR)‑155‑5p and CD11b by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and immunohistochemistry, were assessed following 24 h of ischemia. For in vitro analysis, BV2 mouse microglial cells were cultured and exposed to geniposide (40 µg/ml) + ginsenoside Rg1 (8 µg/ml) during various durations of oxygen‑glucose deprivation (OGD). The expression levels of miR‑155‑5p, pri‑miR‑155 and pre‑miR‑155 were detected by RT‑qPCR. The results demonstrated that increases in brain infarct volume, edema volume, CD11b‑positive cells and miR‑155‑5p levels were alleviated following geniposide + ginsenoside administration in rats exposed to ischemia. Furthermore, geniposide + ginsenoside Rg1 treatment suppressed the miR‑155‑5p, pri‑miR‑155 and pre‑miR‑155 expression levels in OGD‑injured BV2 microglial cells. The results of the present study demonstrated that tail vein administration of geniposide in combination with ginsenoside Rg1

Inhibition of IFN-γ-Induced Nitric Oxide Dependent Antimycobacterial Activity by miR-155 and C/EBPβ

Directory of Open Access Journals (Sweden)

Yongwei Qin

2016-04-01

Full Text Available miR-155 (microRNA-155 is an important non-coding RNA in regulating host crucial biological regulators. However, its regulatory function in mycobacterium infection remains unclear. Our study demonstrates that miR-155 expression is significantly increased in macrophages after Mycobacterium marinum (M.m infection. Transfection with anti-miR-155 enhances nitric oxide (NO synthesis and decreases the mycobacterium burden, and vice versa, in interferon γ (IFN-γ activated macrophages. More importantly, miR-155 can directly bind to the 3′UTR of CCAAT/enhancer binding protein β (C/EBPβ, a positive transcriptional regulator of nitric oxide synthase (NOS2, and regulate C/EBPβ expression negatively. Knockdown of C/EBPβ inhibit the production of nitric oxide synthase and promoted mycobacterium survival. Collectively, these data suggest that M.m-induced upregulation of miR-155 downregulated the expression of C/EBPβ, thus decreasing the production of NO and promoting mycobacterium survival, which may provide an insight into the function of miRNA in subverting the host innate immune response by using mycobacterium for its own profit. Understanding how miRNAs partly regulate microbicidal mechanisms may represent an attractive way to control tuberculosis infectious.

Microstructure and high temperature oxidation resistance of in-situ synthesized TiN/Ti{sub 3}Al intermetallic composite coatings on Ti6Al4V alloy by laser cladding process

Energy Technology Data Exchange (ETDEWEB)

Liu, Hongxi, E-mail: piiiliuhx@sina.com; Zhang, Xiaowei; Jiang, Yehua; Zhou, Rong

2016-06-15

High temperature anti-oxidation TiN/Ti{sub 3}Al intermetallic composite coatings were fabricated with the powder and AlN powder on Ti6Al4V titanium alloy surface by 6 kW transverse-flow CO{sub 2} laser apparatus. The chemical composition, morphology and microstructure of the TiN/Ti{sub 3}Al composite coatings were characterized by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). In order to evaluate the high temperature oxidation resistance of TiN/Ti{sub 3}Al coating, the isothermal oxidation test was performed in a high temperature resistance furnace at 600 °C and 800 °C, respectively. The result shows that the composite coating has a rapidly solidified fine microstructure consisting of TiN primary phase (granular-like, flake-like or dendrites), with an even distribution in Ti{sub 3}Al matrix. It indicates that a physical and chemical reaction between Ti powder and AlN powder has completely occurred under the laser irradiation condition. In addition, the microhardness of the TiN/Ti3Al intermetallic composite coating is 3.4 times higher than that of the Ti6Al4V alloy substrate and reaches 844 HV{sub 0.2}. The high temperature oxidation behavior test reveals that the high temperature oxidation resistance of TiN/Ti{sub 3}Al composite coating is much better than that of titanium alloy substrate. The excellent high temperature oxidation resistance of TiN/Ti{sub 3}Al intermetallic composite coating is attributed to the formation of reinforced phases TiN, Al{sub 2}O{sub 3} and TiO{sub 2}. The laser cladding TiN/Ti{sub 3}Al intermetallic composite coating is anticipated to be a promising high temperature oxidation resistance coating for Ti6Al4V alloy. - Highlights: • In-situ TiN/Ti{sub 3}Al composite coating was synthesized on Ti6Al4V alloy by laser cladding. • The influence of Ti and AlN molar ratio on the microstructure of the coating was studied. • The TiN/Ti{sub 3}Al intermetallic

Influence of manganese, carbon and nitrogen on high-temperature strength of Fe-Cr-Mn austenitic alloys

International Nuclear Information System (INIS)

Hosoi, Y.; Okazaki, Y.; Wade, N.; Miyahara, K.

1990-01-01

High Mn-Cr-Fe base alloys are candidates for the first wall material of fusion reactors because of rapid decay of radioactivity of the alloys after neutron irradiation compared with that of Ni-Cr-Fe base alloys. Their high temperature properties, however, are not clearly understood at present. In this paper, a study has been made of the effects of Mn, C and N content on the high-temperature tensile strength and creep properties of a 12% CR-Fe base alloy. Mn tends to decrease tensile strength and proof stress at intermediate temperatures. At higher temperatures in the austenite range, however, tensile properties scarcely depend on Mn content. C and N additions improve the tensile properties markedly. The combined addition of 0.2%C and 0.2%N to a 12%Cr-15%Mn-Fe base alloy makes the strength at 873K as high as that of a modified type 316 stainless steel. Combined alloying with C and N also improves the creep strength. Cold working is very useful in increasing the creep strength because of the finely dispersed precipitates in the matrix during creep. From these results, Fe-12%Cr-15%Mn-15%Mn-0.2%c-0.2%N is recommended as one of the most suitable alloys in this system for high temperature usage. (author)

Effect of mechanical vibrations on the wear behavior of AZ91 Mg alloy

Science.gov (United States)

Chaturvedi, V.; Pandel, U.; Sharma, A.

2018-02-01

AZ91 Mg alloy is the most promising alloy used for structural applications. The vibration induced methods are effective and economic viable in term of mechanical properties. Sliding wear tests were performed on AZ91 Mg alloy using a pin-on- disc configuration. Wear rates were measured at 5 N and 10N at a sliding velocity of 1m/s for varied frequency within the range of 5- 25Hz and a constant amplitude of 2mm. Microstructures of worn surfaces and wear debris were characterized by field emission scanning electron microscopy (FESEM). It is observed that wear resistance of vibrated AZ91 alloy at 15Hz frequency ad 2mm amplitude was superior than cast AZ91 Mg alloy. Finer grain size and equiaxed grain shape both are important parameters for better wear resistance in vibrated AZ91 Mg alloys. FESEM analysis revealed that wear is considerably affected due to frictional heat generated by the relative motion between AZ91 Mg alloy and EN31 steel surface. No single mechanism was responsible for material loss.

21 CFR 14.155 - Fees and compensation pertaining to a color additive advisory committee.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Fees and compensation pertaining to a color additive advisory committee. 14.155 Section 14.155 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... deposits and fees required by this section are to be paid by money order, bank draft, or certified check...

Oxidation behaviour of U2Ti alloy in dry air

International Nuclear Information System (INIS)

Roy, S.P.; Gupta, N.K.; Jat, Ram Avtar; Parida, S.C.; Mukerjee, S.K.

2016-01-01

U 2 Ti alloy is being considered as promising storage material for storage of hydrogen isotopes. However, the absorption capacity of this reactive alloy can be affected due to presence of oxygen in the process gas. Hence, it is necessary to know the kinetic of this alloy in presence of oxygen. In this study, U 2 Ti alloy was prepared by arc melting method followed by vacuum annealing. The alloy was characterized by XRD, SEM and EDX methods. The isothermal oxidation behaviour of U 2 Ti alloy was investigated in the temperature range of 548-623 K in dry air for 24 hours by using thermo gravimetric technique. The oxidation curves are shown. The oxidation curves were analysed using the rate equation: (Δm/a) n = kt, where, (Δm/a) is the mass gain per unit area, n is the power exponent, k is the rate constant and t is time in (seconds). Analysis of the results shows that the oxidation reaction follows linear rate law (n ~ 1). Using the linear rate law, the rate constant (k) of oxidation reaction was evaluated at each temperature in the range 548-623 K. The variation of (ln k) with reciprocal temperature is shown. The activation energy of this oxidation reaction in the temperature range 548-623 K was calculated using the Arrhenius equation and found to be 76 kJ/mol. The XRD analysis of the oxidation products was found to be U 3 O 8 and TiO 2 . (author)

Constant Load SCC Initiation Response of Alloy 22 (UNS N06022), Titanium Grade 7 and Stainless Steels at 1050C