Fluorescent Glycine-Coated Silver Nanoparticles as Bio-Imaging Agents for the Neural Stem Cells

We study experimentally the photoluminescence of small glycine-coated silver nanoparticles and their application as the bio-imaging markers of the neural stem cells. In addition we study nanoparticle’s toxic effects on the neural stem cells. Glycine-coated silver nanoparticles were synthesized using a thermal reduction of silver nitrate in a glycine matrix and size-separated via centrifugation. The properties of the nanoparticles were characterized using transmission electron microscopy, extinction and photoluminescence spectroscopy. Our results indicate that the nanoparticles have deleterious effects on the cells and showed an amplified increase in their death rates. In fixed cells the particles penetrate the membranes within an hour and 25 minutes of incubation, but do not penetrate into the body of the cell

Formation Processes of Nanocomposite Strengthening Particles in Rapidly Quenched Al-Sc-Zr Alloys

Decomposition processes of supersaturated solid solution of aluminium alloys alloyed with Sc and Zr have been studied in the work. The binary hypereutectic Al-Sc alloys, hyperperitectic Al-Zr alloys and ternary Al-Sc-Zr alloys were chosen. Alloys were obtained by the melt-spinning. Melts were quenched from temperatures of Т = 1000 C and Т = 1400 ºC. The study of the structure of rapidly solidifyed binary Al alloys alloyed with Sc and Zr showed that the crystallization of anomalously supersaturated solid solution (Tquen. = 1400 ºC) or the crystallization with the formation of "fan" structure (Tquen. = 1000 ºC) are possible depending on the quenching temperature of the melt. The decomposition of anomalously supersaturated solid solution is continuous, with the precipitation of nano-sized spherical Al3X (X-Sc, Zr) particles of L12-ordered phase which is isomorphous to matrix. It was found that the loss of thermal stability of Al-Sc alloys is due to the loss of coherence of the strengthening Al3Sc phase. In Al-Zr alloys the loss of strength is due to the formation of a stable tetragonal DO23-ordered A13Zr phase. After co-alloying of Al by Sc and Zr a bimodal grained structure was observed for the hypereutectic ternary alloy (Tquen. = 400ºC). Nano-sized grains of 50-60 nm were present on the boundaries of 1-2 µm large-sized grains. TEM shows the formation of nanocomposite Al3Zr/Al3Sc particles. The formation of Al3Zr shell changes the nature of the interfacial fit of the particle with the matrix and slows down the decomposition during the coalescence. Ternary Al-Sc-Zr alloys have significantly higher thermal stability during aging as compared to binary Al-Sc and Al-Zr alloys. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2488

Effect of Ultrasonic Impact Treatment on the Structure and Properties of Al-Mg-Si Alloy

The study of the effect of ultrasonic impact treatment on the structure of Al-Mg-Si alloy surface showed that the initial structural state of the alloy significantly affected the mechanism of relaxation of internal stresses generated by shock-cyclic loading. The formation of orientation chaos observed in pre-homogenized alloy. Many nanoscale areas (20-50 nm wide and up to 80 nm long) of re-orientation matrix with random orientation formed on the surface of the specimen. After aging of the alloy to form a metastable phase, relaxation was due to the formation of non-crystallographic orientation bands with a high density of dislo-cations and ragged dislocation boundaries. It was found that the fragmentation of matrix or grain refine-ment was not observed during ultrasonic impact treatment of Al-Mg-Si alloy. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3527

Structural changes in friction-stir welded Al-Li-Cu-Sc-Zr (1460) alloy

Structure and properties of Al-2.3%Li-3%Cu-0.1%Sc-0.1%Zr (1460) were studied after FSW on thin cold-rolled sheets with the thickness of 2mm. Sheets were aged in the T8mode. During FSW, severe plastic deformation and material flow occurs at the temperature lower than melting temperature. Welding was performed at the tool rotation speed 2880 rps. The tool was moved along the weld joint at the constant speed 16m/h. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2058

Microstructure Investigation of the Spark Plasma Sintered Cu—Al—Ni Shape Memory Material

Исследована микроструктура компактов Cu—13,0Al—3,9Ni—0,4Ti—0,2Cr масс.%, спечённых плазменно-искровым методом из электроэрозионных порошков, изготовленных из мастер-сплава в жидком аргоне.Досліджено мікроструктуру компактів Cu—13,0Al—3,9Ni—0,4Ti—0,2Cr ваг.% спечених плазмово-іскровим методом із електроерозійних порошків, виготовлених із мастер-стопу в рідкому арґоні.The microstructure of Cu—13.0Al—3.9Ni—0.4Ti—0.2Cr wt.% compacts sintered by spark plasma method from powders prepared by spark-erosion method in liquid argon from master alloy is investigated

Fluorescent Glycine-Coated Silver Nanoparticles as Bio-Imaging Agents for the Neural Stem Cells

We study experimentally the photoluminescence of small glycine-coated silver nanoparticles and their application as the bio-imaging markers of the neural stem cells. In addition we study nanoparticle’s toxic effects on the neural stem cells. Glycine-coated silver nanoparticles were synthesized using a thermal reduction of silver nitrate in a glycine matrix and size-separated via centrifugation. The properties of the nanoparticles were characterized using transmission electron microscopy, extinction and photoluminescence spectroscopy. Our results indicate that the nanoparticles have deleterious effects on the cells and showed an amplified increase in their death rates. In fixed cells the particles penetrate the membranes within an hour and 25 minutes of incubation, but do not penetrate into the body of the cell

Temperature dependence of specific magnetization of metal carbon nano-composites synthesized by arc discharge in liquid

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.Many of unusual physical and chemical properties of nanoparticles are defined by high ratio of their surface area to volume. Possibilities of changing surface area and its chemical composition open far-reaching perspectives for synthesis of new magnetic materials. Evaporation of metals in carbon-containing liquids or simultaneously with graphite allows the preparation of nanometallic particles in the carbon matrix which properties are scantily known. In the present work, Me-C composites have been produced by the arc discharge method in toluene using a powder metal anode (ADLP); their structure, phase composition and magnetic properties have been studied. The performed studies have shown that Me-C composites have a significantly changed phase composition. α-Fe powder transforms into Fe3C carbide almost completely, and solid carbon solution in nickel, Ni-C forms in the Ni powder. Heating the synthesized nanocomposites also leads to the change in their phase composition: after heating, a crystalline phase, Ni-C disappears in the Ni(B-2) powder, and oxides, FeO and Fe3O4 appear in the powder Fe(B-5-2) as well as the ratio of crystalline phases, α-Fe and Fe3С changes

Pion-Photon Transition Form Factor and Pion Distribution Amplitude in QCD: Facing the Enigmatic Behavior of the BaBar Data

We present an extended analysis of the data for the pion-photon transition form factor from different experiments, CELLO, CLEO, and BaBar, and discuss various theoretical approaches which try to reason from them. We focus on the divergent behavior of the BaBar data for the pion and those for the $\eta(\eta')$ pseudoscalar mesons and comment on recently proposed explanations for this discrepancy. We argue that it is not possible at present to accommodate these data within the standard QCD framework self-consistently.Comment: 5 pages, 2 figures, talk presented by the second author at the International Workshop on e^+e^- collisions from phi to psi (PHIPSI11), Novosibirsk (Russia), Sept. 19--22, 201

The forward physics facility at the high-luminosity LHC

High energy collisions at the High-Luminosity Large Hadron Collider (LHC) produce a large number of particles along the beam collision axis, outside of the acceptance of existing LHC experiments. The proposed Forward Physics Facility (FPF), to be located several hundred meters from the ATLAS interaction point and shielded by concrete and rock, will host a suite of experiments to probe standard model (SM) processes and search for physics beyond the standard model (BSM). In this report, we review the status of the civil engineering plans and the experiments to explore the diverse physics signals that can be uniquely probed in the forward region. FPF experiments will be sensitive to a broad range of BSM physics through searches for new particle scattering or decay signatures and deviations from SM expectations in high statistics analyses with TeV neutrinos in this low-background environment. High statistics neutrino detection will also provide valuable data for fundamental topics in perturbative and non-perturbative QCD and in weak interactions. Experiments at the FPF will enable synergies between forward particle production at the LHC and astroparticle physics to be exploited. We report here on these physics topics, on infrastructure, detector, and simulation studies, and on future directions to realize the FPF's physics potential