1,025 research outputs found

    Controlled light-matter coupling for a single quantum dot embedded in a pillar microcavity using far-field optical lithography

    Full text link
    Using far field optical lithography, a single quantum dot is positioned within a pillar microcavity with a 50 nm accuracy. The lithography is performed in-situ at 10 K while measuring the quantum dot emission. Deterministic spectral and spatial matching of the cavity-dot system is achieved in a single step process and evidenced by the observation of strong Purcell effect. Deterministic coupling of two quantum dots to the same optical mode is achieved, a milestone for quantum computing.Comment: Modified version: new title, additional experimental data in figure

    The influence of the microstructure morphology of two phase Ti-6Al-4V alloy on the mechanical properties of diffusion bonded joints

    Get PDF
    The influence of ultra fine grained (UFG) and coarse grained (CG) microstructure of the titanium alloy Ti-6Al-4V on the strength of a diffusion bonded (DB) joint was studied using a laboratory DB fixture and a new shear test rig. The DB process was carried out at 725Β°C and 825Β°C during 2 and 4 hours in a vacuum furnace. Coarsening of grain structure resulting from different DB cycles was quantified. The chain pores were observed at 725Β°C for both microstructure conditions bonded during 2 hours. The increase of bonding time up to 4 hours leads to subsequent elimination of the pores. The UFG samples bonded at 725Β°C showed a higher level of the shear strength than CG samples for both bonding times. The CG material demonstrated the highest shear strength after 4 hours of DB bonding at 825Β°C. The increase of the creep deformation of UFG samples when compared to the CG condition was observed as a result of DB at of 725Β° C during 4 hours

    Polystyrene-based nanocomposites with different fillers: fabrication and mechanical properties

    Full text link
    The paper presents a comprehensive analysis of elastic properties of polystyrene-based nanocomposites filled with different types of inclusions: small spherical particles (SiO2 and Al2O3), alumosilicates (montmorillonite, halloysite natural tubules and Mica) and carbon nanofillers (carbon black and multi-walled carbon nanotubes). Composites were fabricated by melt technology. The analysis of composite melts showed that the introduction of Montmorillonite, Multi-walled carbon nanotubes, and Al2O3 particles provided an increase in melt viscosity by an average of 2 to 5 orders of magnitude over the pure polystyrene. Block samples of composites with different filler concentrations were prepared, and their linear and nonlinear elastic properties were studied. The introduction of more rigid particles led to a more profound increase in the elastic modulus of the composite, with the highest rise of about 80% obtained with carbon fillers. Carbon black particles provided also an enhanced strength at break of about 20% higher than that of pure polystyrene. The nonlinear elastic moduli of composites were shown to be more sensitive to addition of filler particles to the polymer matrix than the linear ones. The nonlinearity coefficient Ξ²\beta comprising the combination of linear and nonlinear elastic moduli of a material demonstrated considerable changes correlating with changes of the Young's modulus. The absolute value of Ξ²\beta showed rise in 1.5-1.6 times in the CB- and HNT-containing composites as compared to that of pure PS. The changes in nonlinear elasticity of fabricated composites were compared with measurements of the parameters of bulk nonlinear strain waves in them. Variations of wave velocity and decay decrement correlated with observed enhancement of materials nonlinearity

    POWER TRAINING OF STUDENTS WITH THE HELP OF WEIGHT FITNESS IN PHYSICAL EDUCATION CLASSES

    Full text link
    The methodology of strength training of students is presented in order to increase the level of knowledge and increase the level of knowledge and improve the level of knowledge. The article describes that physical exercise is one of the most effective means of developing physical qualities in a person. And strength training with weights is one of the best ways to in-crease the students' strengths and motivation for pursuing classes with them. Statement of the relevance of the problem of low motor activity of youth, which leads to the success of quality and a drop in health. It is noted that weight lifting exercises contribute to the positive mood of students and high interest among students, as they can observe their progress in the process of classes. The pedagogical experiment, which was conducted on the basis of the Ural Pedagogical University, is described in detail.ΠŸΡ€Π΅Π΄ΡΡ‚Π°Π²Π»Π΅Π½Π° ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΈΠΊΠ° силовой Ρ‚Ρ€Π΅Π½ΠΈΡ€ΠΎΠ²ΠΊΠΈ студСнтов Π² цСлях увСличСния интСрСса ΠΈ ΠΌΠΎΡ‚ΠΈΠ²Π°Ρ†ΠΈΠΈ ΠΊ занятиям физичСской ΠΊΡƒΠ»ΡŒΡ‚ΡƒΡ€ΠΎΠΉ ΠΈ ΠΏΠΎΠ²Ρ‹ΡˆΠ΅Π½ΠΈΡ уровня Π·Π΄ΠΎΡ€ΠΎΠ²ΡŒΡ ΠΌΠΎΠ»ΠΎΠ΄Π΅ΠΆΠΈ. Π‘Ρ‚Π°Ρ‚ΡŒΡ описываСт, Ρ‡Ρ‚ΠΎ ΠΎΠ΄Π½ΠΈΠΌ ΠΈΠ· эффСктивных срСдств развития физичСских качСств Ρƒ Ρ‡Π΅Π»ΠΎΠ²Π΅ΠΊΠ° являСтся физичСскиС упраТнСния. А силовая Ρ‚Ρ€Π΅Π½ΠΈΡ€ΠΎΠ²ΠΊΠ° с гирями – ΠΎΠ΄ΠΈΠ½ ΠΈΠ· Π»ΡƒΡ‡ΡˆΠΈΡ… способов увСличСния силовых способностСй студСнтов ΠΈ ΠΌΠΎΡ‚ΠΈΠ²Π°Ρ†ΠΈΠΈ ΠΊ занятиям Ρƒ Π½ΠΈΡ…. Π˜Π·Π»Π°Π³Π°Π΅Ρ‚ΡΡ Π°ΠΊΡ‚ΡƒΠ°Π»ΡŒΠ½ΠΎΡΡ‚ΡŒ ΠΏΡ€ΠΎΠ±Π»Π΅ΠΌΡ‹ Π½ΠΈΠ·ΠΊΠΎΠΉ Π΄Π²ΠΈΠ³Π°Ρ‚Π΅Π»ΡŒΠ½ΠΎΠΉ активности ΠΌΠΎΠ»ΠΎΠ΄Π΅ΠΆΠΈ, которая ΠΏΡ€ΠΈΠ²ΠΎΠ΄ΠΈΡ‚ ΠΊ сниТСнию физичСских качСств ΠΈ падСнию Π·Π΄ΠΎΡ€ΠΎΠ²ΡŒΡ. ΠžΡ‚ΠΌΠ΅Ρ‡Π΅Π½ΠΎ, Ρ‡Ρ‚ΠΎ занятия Π³ΠΈΡ€Π΅Π²Ρ‹ΠΌ фитнСсом ΡΠΏΠΎΡΠΎΠ±ΡΡ‚Π²ΡƒΡŽΡ‚ ΠΏΠΎΠ»ΠΎΠΆΠΈΡ‚Π΅Π»ΡŒΠ½ΠΎΠΌΡƒ Π½Π°ΡΡ‚Ρ€ΠΎΡŽ Π·Π°Π½ΠΈΠΌΠ°ΡŽΡ‰ΠΈΡ…ΡΡ ΠΈ высоким интСрСсом Ρƒ студСнтов, Ρ‚Π°ΠΊ ΠΊΠ°ΠΊ ΠΎΠ½ΠΈ ΠΌΠΎΠ³Π»ΠΈ Π½Π°Π±Π»ΡŽΠ΄Π°Ρ‚ΡŒ свой прогрСсс Π² процСссС занятий. ΠŸΠΎΠ΄Ρ€ΠΎΠ±Π½ΠΎ описываСтся пСдагогичСский экспСримСнт, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹ΠΉ проводился Π½Π° Π±Π°Π·Π΅ Π£Ρ€Π°Π»ΡŒΡΠΊΠΎΠ³ΠΎ пСдагогичСского УнивСрситСта

    Thermobaric synthesis, structure, and properties of Dy x Cu 3V4O12

    Full text link
    The perovskite-like compound Dy x Cu3V 4O12 (x = 0.67-0.75) is synthesized under high pressure (P = 4.0-9.0 GPa) and temperature (T = 1000 C). Its crystal structure is determined (Im-3 space group, Z = 2, a = 7.29348(7) Γ…) by means of powder X-ray diffraction. The basic lengths and bond angles are defined. It is found that the high-pressure phase of Dy x Cu3V 4O12 is characterized by metallic conductivity and paramagnetic properties. Β© 2013 Allerton Press, Inc
    • …
    corecore