389 research outputs found

    Mechanical Properties of Thermoplastic Variable-Angle Composite Laminations for Conical Shells

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    Thermoplastic composite automated fiber placement technology, as one of the extreme manufacturing technologies for large or extra large composite components with complex surface shapes, has been widely used in the field of aerospace vehicles. This paper takes 8 lamination groups with different initial placement angles generated by the conical shell variable angle placement algorithm as research objects. Variable angle placement algorithm for conical shell and finite element model establishment method for thermoplastic composite laminations of variable angle with different initial placement angles are presented. Static, modal and buckling analyses are conducted for each group. The results show that stress-strain relation, modal and buckling strength of variable-angle laminations vary regularly with the initial placement angle.ВСхнология автоматичСской ΡƒΠΊΠ»Π°Π΄ΠΊΠΈ тСрмопластичного ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ‚Π½ΠΎΠ³ΠΎ Π²ΠΎΠ»ΠΎΠΊΠ½Π°, ΡΠ²Π»ΡΡŽΡ‰Π°ΡΡΡ ΠΎΠ΄Π½ΠΎΠΉ ΠΈΠ· Ρ€Π°Π΄ΠΈΠΊΠ°Π»ΡŒΠ½Ρ‹Ρ… Ρ‚Π΅Ρ…Π½ΠΎΠ»ΠΎΠ³ΠΈΠΉ получСния Π±ΠΎΠ»ΡŒΡˆΠΈΡ… ΠΈΠ»ΠΈ ΠΎΡ‡Π΅Π½ΡŒ Π±ΠΎΠ»ΡŒΡˆΠΈΡ… ΠΊΠΎΠΌΠΏΠΎΠ½Π΅Π½Ρ‚ΠΎΠ² ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ‚ΠΎΠ² с комплСксными Ρ„ΠΎΡ€ΠΌΠ°ΠΌΠΈ повСрхности, ΡˆΠΈΡ€ΠΎΠΊΠΎ ΠΈΡΠΏΠΎΠ»ΡŒΠ·ΡƒΠ΅Ρ‚ΡΡ Π² Π°Π²ΠΈΠ°Ρ†ΠΈΠΎΠ½Π½ΠΎ-космичСской ΠΏΡ€ΠΎΠΌΡ‹ΡˆΠ»Π΅Π½Π½ΠΎΡΡ‚ΠΈ. Π’ качСствС ΠΎΠ±ΡŠΠ΅ΠΊΡ‚ΠΎΠ² исслСдования использовали восСмь Π³Ρ€ΡƒΠΏΠΏ слоистых ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»ΠΎΠ² с Ρ€Π°Π·Π»ΠΈΡ‡Π½Ρ‹ΠΌΠΈ ΡƒΠ³Π»Π°ΠΌΠΈ конструктивного размСщСния, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Π΅ Π±Ρ‹Π»ΠΈ созданы с ΠΏΠΎΠΌΠΎΡ‰ΡŒΡŽ Π°Π»Π³ΠΎΡ€ΠΈΡ‚ΠΌΠ° размСщСния ΠΏΠ΅Ρ€Π΅ΠΌΠ΅Π½Π½ΠΎΠ³ΠΎ ΡƒΠ³Π»Π° коничСской ΠΎΠ±ΠΎΠ»ΠΎΡ‡ΠΊΠΈ. ΠŸΡ€Π΅Π΄ΡΡ‚Π°Π²Π»Π΅Π½Ρ‹ Π°Π»Π³ΠΎΡ€ΠΈΡ‚ΠΌ размСщСния ΠΏΠ΅Ρ€Π΅ΠΌΠ΅Π½Π½ΠΎΠ³ΠΎ ΡƒΠ³Π»Π° для коничСской ΠΎΠ±ΠΎΠ»ΠΎΡ‡ΠΊΠΈ ΠΈ модСль Π½Π° основС ΠΌΠ΅Ρ‚ΠΎΠ΄Π° ΠΊΠΎΠ½Π΅Ρ‡Π½Ρ‹Ρ… элСмСнтов для тСрмопластичных слоистых ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ‚ΠΎΠ² с ΠΏΠ΅Ρ€Π΅ΠΌΠ΅Π½Π½Ρ‹ΠΌ ΡƒΠ³Π»ΠΎΠΌ. Для ΠΊΠ°ΠΆΠ΄ΠΎΠΉ Π³Ρ€ΡƒΠΏΠΏΡ‹ ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»ΠΎΠ² ΠΏΡ€ΠΎΠ²Π΅Π΄Π΅Π½Ρ‹ статистичСский Π°Π½Π°Π»ΠΈΠ·, исслСдованиС ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ разлоТСния ΠΏΠΎ собствСнным Ρ„ΠΎΡ€ΠΌΠ°ΠΌ ΠΈ расчСт устойчивости. УстановлСно, Ρ‡Ρ‚ΠΎ Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡ‚ΡŒ напряТСниС–дСформация, модальная ΠΏΡ€ΠΎΡ‡Π½ΠΎΡΡ‚ΡŒ ΠΈ ΠΏΡ€ΠΎΡ‡Π½ΠΎΡΡ‚ΡŒ ΠΏΡ€ΠΈ ΠΏΡ€ΠΎΠ΄ΠΎΠ»ΡŒΠ½ΠΎΠΌ ΠΈΠ·Π³ΠΈΠ±Π΅ слоистых ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»ΠΎΠ² с ΠΏΠ΅Ρ€Π΅ΠΌΠ΅Π½Π½Ρ‹ΠΌ ΡƒΠ³Π»ΠΎΠΌ пСриодичСски ΠΈΠ·ΠΌΠ΅Π½ΡΡŽΡ‚ΡΡ Π² зависимости ΠΎΡ‚ ΡƒΠ³Π»Π° конструктивного размСщСния.ВСхнологія Π°Π²Ρ‚ΠΎΠΌΠ°Ρ‚ΠΈΡ‡Π½ΠΎΠ³ΠΎ укладання тСрмопластичного ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ‚Π½ΠΎΠ³ΠΎ Π²ΠΎΠ»ΠΎΠΊΠ½Π°, Ρ‰ΠΎ Ρ” ΠΎΠ΄Π½Ρ–Ρ”ΡŽ Π· Ρ€Π°Π΄ΠΈΠΊΠ°Π»ΡŒΠ½ΠΈΡ… Ρ‚Π΅Ρ…Π½ΠΎΠ»ΠΎΠ³Ρ–ΠΉ отримання Π²Π΅Π»ΠΈΠΊΠΈΡ… Π°Π±ΠΎ Π΄ΡƒΠΆΠ΅ Π²Π΅Π»ΠΈΠΊΠΈΡ… ΠΊΠΎΠΌΠΏΠΎΠ½Π΅Π½Ρ‚Ρ–Π² ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ‚Ρ–Π² Ρ–Π· комплСксними Ρ„ΠΎΡ€ΠΌΠ°ΠΌΠΈ ΠΏΠΎΠ²Π΅Ρ€Ρ…Π½Ρ–, ΡˆΠΈΡ€ΠΎΠΊΠΎ Π²ΠΈΠΊΠΎΡ€ΠΈΡΡ‚ΠΎΠ²ΡƒΡ”Ρ‚ΡŒΡΡ Π² Π°Π²Ρ–Π°Ρ†Ρ–ΠΉΠ½ΠΎ-космічній промисловості. ΠžΠ±β€™Ρ”ΠΊΡ‚ΠΎΠΌ дослідТСння слугували вісім Π³Ρ€ΡƒΠΏ ΡˆΠ°Ρ€ΡƒΠ²Π°Ρ‚ΠΈΡ… ΠΌΠ°Ρ‚Π΅Ρ€Ρ–Π°Π»Ρ–Π² Ρ–Π· Ρ€Ρ–Π·Π½ΠΈΠΌΠΈ ΠΊΡƒΡ‚Π°ΠΌΠΈ конструктивного розміщСння, які ΠΎΡ‚Ρ€ΠΈΠΌΠ°Π½ΠΎ Π·Π° допомогою Π°Π»Π³ΠΎΡ€ΠΈΡ‚ΠΌΠ° розміщСння Π·ΠΌΡ–Π½Π½ΠΎΠ³ΠΎ ΠΊΡƒΡ‚Π° ΠΊΠΎΠ½Ρ–Ρ‡Π½ΠΎΡ— ΠΎΠ±ΠΎΠ»ΠΎΠ½ΠΊΠΈ. ΠŸΡ€Π΅Π΄ΡΡ‚Π°Π²Π»Π΅Π½ΠΎ Π°Π»Π³ΠΎΡ€ΠΈΡ‚ΠΌ розміщСння Π·ΠΌΡ–Π½Π½ΠΎΠ³ΠΎ ΠΊΡƒΡ‚Π° для ΠΊΠΎΠ½Ρ–Ρ‡Π½ΠΎΡ— ΠΎΠ±ΠΎΠ»ΠΎΠ½ΠΊΠΈ Ρ– модСль Π½Π° основі ΠΌΠ΅Ρ‚ΠΎΠ΄Ρƒ скінчСнних Π΅Π»Π΅ΠΌΠ΅Π½Ρ‚Ρ–Π² для тСрмопластичних ΡˆΠ°Ρ€ΡƒΠ²Π°Ρ‚ΠΈΡ… ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ‚Ρ–Π² Π·Ρ– Π·ΠΌΡ–Π½Π½ΠΈΠΌ ΠΊΡƒΡ‚ΠΎΠΌ. Для ΠΊΠΎΠΆΠ½ΠΎΡ— Π³Ρ€ΡƒΠΏΠΈ ΠΌΠ°Ρ‚Π΅Ρ€Ρ–Π°Π»Ρ–Π² ΠΏΡ€ΠΎΠ²Π΅Π΄Π΅Π½ΠΎ статистичний Π°Π½Π°Π»Ρ–Π·, дослідТСння ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ розкладання Π·Π° власними Ρ„ΠΎΡ€ΠΌΠ°ΠΌΠΈ Ρ– Ρ€ΠΎΠ·Ρ€Π°Ρ…ΡƒΠ½ΠΎΠΊ стійкості. УстановлСно, Ρ‰ΠΎ Π·Π°Π»Π΅ΠΆΠ½Ρ–ΡΡ‚ΡŒ напруТСння–дСформація, модальна ΠΌΡ–Ρ†Π½Ρ–ΡΡ‚ΡŒ Ρ– ΠΌΡ–Ρ†Π½Ρ–ΡΡ‚ΡŒ ΠΏΡ€ΠΈ ΠΏΠΎΠ·Π΄ΠΎΠ²ΠΆΠ½ΡŒΠΎΠΌΡƒ Π·Π³ΠΈΠ½Ρ– ΡˆΠ°Ρ€ΡƒΠ²Π°Ρ‚ΠΈΡ… ΠΌΠ°Ρ‚Π΅Ρ€Ρ–Π°Π»Ρ–Π² Π·Ρ– Π·ΠΌΡ–Π½Π½ΠΈΠΌ ΠΊΡƒΡ‚ΠΎΠΌ ΠΏΠ΅Ρ€Ρ–ΠΎΠ΄ΠΈΡ‡Π½ΠΎ Π·ΠΌΡ–Π½ΡŽΡŽΡ‚ΡŒΡΡ Π² залСТності Π²Ρ–Π΄ ΠΊΡƒΡ‚Π° конструктивного розміщСння

    Coupled superconducting qudit-resonator system: Energy spectrum, state population, and state transition under microwave drive

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    Superconducting quantum multilevel systems coupled to resonators have recently been considered in some applications such as microwave lasing and high-fidelity quantum logical gates. In this work, using an rf-SQUID type phase qudit coupled to a microwave coplanar waveguide resonator, we study both theoretically and experimentally the energy spectrum of the system when the qudit level spacings are varied around the resonator frequency by changing the magnetic flux applied to the qudit loop. We show that the experimental result can be well described by a theoretical model that extends from the usual two-level Jaynes-Cummings system to the present four-level system. It is also shown that due to the small anharmonicity of the phase device a simplified model capturing the leading state interactions fits the experimental spectra very well. Furthermore we use the Lindblad master equation containing various relaxation and dephasing processes to calculate the level populations in the simpler qutrit-resonator system, which allows a clear understanding of the dynamics of the system under the microwave drive. Our results help to better understand and perform the experiments of coupled multilevel and resonator systems and can be applied in the case of transmon or Xmon qudits having similar anharmonicity to the present phase device.This work was supported by the Ministry of Science and Technology of China (Grants No. 2014CB921202, No. 2015CB921104, and No. 2016YFA0300601),the National Natural Science Foundation of China (Grants No. 91321208 and No. 11674380)the Key Research Program of the Chinese Academy of Sciences (Grant No. XDPB08-3)S.H. acknowledges support by the US NSF (PHY-1314861)

    Effects of different probiotics on the gut microbiome and metabolites in the serum and caecum of weaning piglets

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    The objective of the study was to determine the effects of antibiotics, yeast culture (YC), and Lactobacillus culture (LC) on the gut microbiome and metabolites in the serum and caecum of weaning piglets. Twenty-four weaning piglets were divided into four treatment groups: control, antibiotic (1% chlortetracycline), 1.8% yeast culture (YC), and 1.6% Lactobacillus culture groups (LC). Each group had six replicated pens with one pig per pen. Feed and water were available ad libitum. Dietary supplementation with antibiotics, YC and LC increased the abundance of phylum, Firmicutes, and decreased the abundance of phylum, Proteobacteria. Beneficial bacteria such as Lactobacillus and Megasphaera in YC and LC groups increased, whereas the proportion of Shigella was decreased. Genera Alloprevotella and Lachnospira were biomarkers in the control and antibiotic groups, respectively. Phylum, Bacteroidetes, and genus, Collinsella, were biomarkers in the YC group, and Mitsuokella, Anaerotruncus, Syntrophococcus and Sharpea were biomarkers in the LC group. Dietary supplementation with different probiotics changed the serum and caecum metabolite profiles too. Antibiotic supplementation increased the levels of D-mannose, D-glucose, and hexadecanoic acid in the serum, and the levels of myo-inositol, D-mannose and benzenepropanoic acid in the caecum. LC increased the concentrations of D-mannose, cis-9-hexadecenoic acid and heptadecanoic acid in caecum compared with the control group. YC and LC supplementation in the weaning diet could improve the abundance of beneficial bacteria by changing the concentrations of some metabolites in the serum and caecum. Therefore, dietary supplementation with YC or LC could be used as additives instead of antibiotics in weaning piglets.Keywords: antibiotic; lactobacillus culture; yeast culture; high-throughput sequencing; gas chromatography mass spectrometr

    Brachypodium distachyon line Bd3-1 resistance is elicited by the barley stripe mosaic virus triple gene block 1 movement protein

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    Barley stripe mosaic virus North Dakota 18 (ND18), Beijing (BJ), Xinjiang (Xi), Type (TY) and CV21 strains are unable to infect the Brachypodium distachyon Bd3-1 inbred line, which harbours a resistance gene designated Bsr1, but the Norwich (NW) strain is virulent on Bd3-1. Analysis of ND18 and NW genomic RNA reassortants and RNA beta mutants demonstrates that two amino acids within the helicase motif of the triple gene block 1 (TGB1) movement protein have major effects on their Bd3-1 phenotypes. Resistance to ND18 correlates with an arginine residue at TGB1 position 390 (R-390) and a threonine at position 392 (T-392), whereas the virulent NW strain contains lysines (K) at both positions. ND18 TGB1 R390K ((ND)TGB1(R390K)) and (ND)TGB1(T392K) single substitutions, and an (ND)TGB1(R390K,T392K) double mutation resulted in systemic infections of Bd3-1. Reciprocal (ND)TGB1 substitutions into (NW)TGB1 ((NW)TGB1(K390R) and (NW)TGB1(K392T)) failed to affect virulence, implying that K-390 and K-392 compensate for each other. In contrast, an (NW)TGB1(K390R,K392T) double mutant exhibited limited vascular movement in Bd3-1, but developed prominent necrotic streaks that spread from secondary leaf veins. This phenotype, combined with the appearance of necrotic spots in certain ND18 mutants, and necrosis and rapid wilting of Bd3-1 plants after BJ strain ((BJ)TGB1(K390,T392)) inoculations, show that Bd3-1 Bsr1 resistance is elicited by the TGB1 protein and suggest that it involves a hypersensitive response

    Partial Wave Analysis of J/Οˆβ†’Ξ³(K+Kβˆ’Ο€+Ο€βˆ’)J/\psi \to \gamma (K^+K^-\pi^+\pi^-)

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    BES data on J/Οˆβ†’Ξ³(K+Kβˆ’Ο€+Ο€βˆ’)J/\psi \to \gamma (K^+K^-\pi^+\pi^-) are presented. The Kβˆ—KΛ‰βˆ—K^*\bar K^* contribution peaks strongly near threshold. It is fitted with a broad 0βˆ’+0^{-+} resonance with mass M=1800Β±100M = 1800 \pm 100 MeV, width Ξ“=500Β±200\Gamma = 500 \pm 200 MeV. A broad 2++2^{++} resonance peaking at 2020 MeV is also required with width ∼500\sim 500 MeV. There is further evidence for a 2βˆ’+2^{-+} component peaking at 2.55 GeV. The non-Kβˆ—KΛ‰βˆ—K^*\bar K^* contribution is close to phase space; it peaks at 2.6 GeV and is very different from Kβˆ—Kβˆ—Λ‰K^{*}\bar{K^{*}}.Comment: 15 pages, 6 figures, 1 table, Submitted to PL

    A Measurement of Psi(2S) Resonance Parameters

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    Cross sections for e+e- to hadons, pi+pi- J/Psi, and mu+mu- have been measured in the vicinity of the Psi(2S) resonance using the BESII detector operated at the BEPC. The Psi(2S) total width; partial widths to hadrons, pi+pi- J/Psi, muons; and corresponding branching fractions have been determined to be Gamma(total)= (264+-27) keV; Gamma(hadron)= (258+-26) keV, Gamma(mu)= (2.44+-0.21) keV, and Gamma(pi+pi- J/Psi)= (85+-8.7) keV; and Br(hadron)= (97.79+-0.15)%, Br(pi+pi- J/Psi)= (32+-1.4)%, Br(mu)= (0.93+-0.08)%, respectively.Comment: 8 pages, 6 figure

    Measurements of the Mass and Full-Width of the Ξ·c\eta_c Meson

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    In a sample of 58 million J/ψJ/\psi events collected with the BES II detector, the process J/Οˆβ†’Ξ³Ξ·c\psi\to\gamma\eta_c is observed in five different decay channels: Ξ³K+Kβˆ’Ο€+Ο€βˆ’\gamma K^+K^-\pi^+\pi^-, Ξ³Ο€+Ο€βˆ’Ο€+Ο€βˆ’\gamma\pi^+\pi^-\pi^+\pi^-, Ξ³KΒ±KS0Ο€βˆ“\gamma K^\pm K^0_S \pi^\mp (with KS0β†’Ο€+Ο€βˆ’K^0_S\to\pi^+\pi^-), γϕϕ\gamma \phi\phi (with Ο•β†’K+Kβˆ’\phi\to K^+K^-) and Ξ³ppΛ‰\gamma p\bar{p}. From a combined fit of all five channels, we determine the mass and full-width of Ξ·c\eta_c to be mΞ·c=2977.5Β±1.0(stat.)Β±1.2(syst.)m_{\eta_c}=2977.5\pm1.0 ({stat.})\pm1.2 ({syst.}) MeV/c2c^2 and Γηc=17.0Β±3.7(stat.)Β±7.4(syst.)\Gamma_{\eta_c} = 17.0\pm3.7 ({stat.})\pm7.4 ({syst.}) MeV/c2c^2.Comment: 9 pages, 2 figures and 4 table. Submitted to Phys. Lett.
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