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C, N and noble gases in different pH and grain size fractions of pre-solar diamonds from Boriskino chondrite
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Separation of Q from carbon in CR meteorites during stepped combustion
Introduction: The nature of the planetary noble gas carrier (Q) in meteorites remains uncertain. It is known that it is likely to be carbonaceous, but represents only a small fraction of the total macromolecular material. Q is oxidisible with nitric and other oxidizing acids. It seems to be partly destroyed with pyridine and may have an organic structure. Previously, we have shown that during parent body thermal metamorphism Q is less affected than the majority of other carbonaceous materials. If organic matter is graphitized, as has happened in the enstatite chondrite parent bodies, Q remains unaffected. In the present study we have found that Q is also separable from the majority of carbon in type 2 and 3 CR chondrites during stepped combustion. It is possible that this is because Q has become encased within the matrix, in contrast to other carbon phases, during parent body metamorphism
Controlled light-matter coupling for a single quantum dot embedded in a pillar microcavity using far-field optical lithography
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
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
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 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
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
Thermobaric synthesis, structure, and properties of Dy x Cu 3V4O12
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
POWER TRAINING OF STUDENTS WITH THE HELP OF WEIGHT FITNESS IN PHYSICAL EDUCATION CLASSES
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.ΠΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Π° ΠΌΠ΅ΡΠΎΠ΄ΠΈΠΊΠ° ΡΠΈΠ»ΠΎΠ²ΠΎΠΉ ΡΡΠ΅Π½ΠΈΡΠΎΠ²ΠΊΠΈ ΡΡΡΠ΄Π΅Π½ΡΠΎΠ² Π² ΡΠ΅Π»ΡΡ
ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΡ ΠΈΠ½ΡΠ΅ΡΠ΅ΡΠ° ΠΈ ΠΌΠΎΡΠΈΠ²Π°ΡΠΈΠΈ ΠΊ Π·Π°Π½ΡΡΠΈΡΠΌ ΡΠΈΠ·ΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΊΡΠ»ΡΡΡΡΠΎΠΉ ΠΈ ΠΏΠΎΠ²ΡΡΠ΅Π½ΠΈΡ ΡΡΠΎΠ²Π½Ρ Π·Π΄ΠΎΡΠΎΠ²ΡΡ ΠΌΠΎΠ»ΠΎΠ΄Π΅ΠΆΠΈ. Π‘ΡΠ°ΡΡΡ ΠΎΠΏΠΈΡΡΠ²Π°Π΅Ρ, ΡΡΠΎ ΠΎΠ΄Π½ΠΈΠΌ ΠΈΠ· ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΡΡ
ΡΡΠ΅Π΄ΡΡΠ² ΡΠ°Π·Π²ΠΈΡΠΈΡ ΡΠΈΠ·ΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΊΠ°ΡΠ΅ΡΡΠ² Ρ ΡΠ΅Π»ΠΎΠ²Π΅ΠΊΠ° ΡΠ²Π»ΡΠ΅ΡΡΡ ΡΠΈΠ·ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΡΠΏΡΠ°ΠΆΠ½Π΅Π½ΠΈΡ. Π ΡΠΈΠ»ΠΎΠ²Π°Ρ ΡΡΠ΅Π½ΠΈΡΠΎΠ²ΠΊΠ° Ρ Π³ΠΈΡΡΠΌΠΈ β ΠΎΠ΄ΠΈΠ½ ΠΈΠ· Π»ΡΡΡΠΈΡ
ΡΠΏΠΎΡΠΎΠ±ΠΎΠ² ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΡ ΡΠΈΠ»ΠΎΠ²ΡΡ
ΡΠΏΠΎΡΠΎΠ±Π½ΠΎΡΡΠ΅ΠΉ ΡΡΡΠ΄Π΅Π½ΡΠΎΠ² ΠΈ ΠΌΠΎΡΠΈΠ²Π°ΡΠΈΠΈ ΠΊ Π·Π°Π½ΡΡΠΈΡΠΌ Ρ Π½ΠΈΡ
. ΠΠ·Π»Π°Π³Π°Π΅ΡΡΡ Π°ΠΊΡΡΠ°Π»ΡΠ½ΠΎΡΡΡ ΠΏΡΠΎΠ±Π»Π΅ΠΌΡ Π½ΠΈΠ·ΠΊΠΎΠΉ Π΄Π²ΠΈΠ³Π°ΡΠ΅Π»ΡΠ½ΠΎΠΉ Π°ΠΊΡΠΈΠ²Π½ΠΎΡΡΠΈ ΠΌΠΎΠ»ΠΎΠ΄Π΅ΠΆΠΈ, ΠΊΠΎΡΠΎΡΠ°Ρ ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΠΊ ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΡ ΡΠΈΠ·ΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΊΠ°ΡΠ΅ΡΡΠ² ΠΈ ΠΏΠ°Π΄Π΅Π½ΠΈΡ Π·Π΄ΠΎΡΠΎΠ²ΡΡ. ΠΡΠΌΠ΅ΡΠ΅Π½ΠΎ, ΡΡΠΎ Π·Π°Π½ΡΡΠΈΡ Π³ΠΈΡΠ΅Π²ΡΠΌ ΡΠΈΡΠ½Π΅ΡΠΎΠΌ ΡΠΏΠΎΡΠΎΠ±ΡΡΠ²ΡΡΡ ΠΏΠΎΠ»ΠΎΠΆΠΈΡΠ΅Π»ΡΠ½ΠΎΠΌΡ Π½Π°ΡΡΡΠΎΡ Π·Π°Π½ΠΈΠΌΠ°ΡΡΠΈΡ
ΡΡ ΠΈ Π²ΡΡΠΎΠΊΠΈΠΌ ΠΈΠ½ΡΠ΅ΡΠ΅ΡΠΎΠΌ Ρ ΡΡΡΠ΄Π΅Π½ΡΠΎΠ², ΡΠ°ΠΊ ΠΊΠ°ΠΊ ΠΎΠ½ΠΈ ΠΌΠΎΠ³Π»ΠΈ Π½Π°Π±Π»ΡΠ΄Π°ΡΡ ΡΠ²ΠΎΠΉ ΠΏΡΠΎΠ³ΡΠ΅ΡΡ Π² ΠΏΡΠΎΡΠ΅ΡΡΠ΅ Π·Π°Π½ΡΡΠΈΠΉ. ΠΠΎΠ΄ΡΠΎΠ±Π½ΠΎ ΠΎΠΏΠΈΡΡΠ²Π°Π΅ΡΡΡ ΠΏΠ΅Π΄Π°Π³ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΠΉ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½Ρ, ΠΊΠΎΡΠΎΡΡΠΉ ΠΏΡΠΎΠ²ΠΎΠ΄ΠΈΠ»ΡΡ Π½Π° Π±Π°Π·Π΅ Π£ΡΠ°Π»ΡΡΠΊΠΎΠ³ΠΎ ΠΏΠ΅Π΄Π°Π³ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π£Π½ΠΈΠ²Π΅ΡΡΠΈΡΠ΅ΡΠ°
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