20,822 research outputs found

    Magnetothermodynamics In SSX: Measuring The Equations Of State Of A Compressible Magnetized Plasma

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    Magnetothermodynamics is the study of compression and expansion of magnetized plasma with an eye toward identifying equations of state (EOSs) for magneto-inertial fusion experiments. We present recent results from Swarthmore Spheromak Experiment (SSX) experiments on the thermodynamics of compressed magnetized plasmas called Taylor states. In these experiments, we generate twisted flux ropes of magnetized, relaxed plasma accelerated from one end of a 1.5-m-long copper flux conserver and observe their compression in a closed conducting boundary installed at the other end. Plasma parameters are measured during compression. The instances of ion heating during compression are identified by constructing a pressure-volume diagram using measured density, temperature, and volume of the magnetized plasma. While we only measure compression up to 30%, we speculate that if higher compression ratios could be achieved, the compressed Taylor states could form the basis of a new kind of fusion engine. The theoretically predicted magnetohydrodynamic (MHD) and double-adiabatic [Chew-Goldberger-Low (CGL)] EOSs are compared to experimental measurements to estimate the adiabatic nature of the compressed plasma. Since our magnetized plasmas relax to an equilibrium described by MHD, one might expect their thermodynamics to be governed by the corresponding EOS. However, we find that the MHD EOS is not supported by our data. Our results are more consistent with the parallel CGL EOS suggesting that these weakly collisional plasmas have most of their proton energy in the direction parallel to the magnetic field

    Magnetothermodynamics In SSX: Measuring The Equations Of State Of A Compressible Magnetized Plasma

    Get PDF
    Magnetothermodynamics is the study of compression and expansion of magnetized plasma with an eye toward identifying equations of state (EOSs) for magneto-inertial fusion experiments. We present recent results from Swarthmore Spheromak Experiment (SSX) experiments on the thermodynamics of compressed magnetized plasmas called Taylor states. In these experiments, we generate twisted flux ropes of magnetized, relaxed plasma accelerated from one end of a 1.5-m-long copper flux conserver and observe their compression in a closed conducting boundary installed at the other end. Plasma parameters are measured during compression. The instances of ion heating during compression are identified by constructing a pressure-volume diagram using measured density, temperature, and volume of the magnetized plasma. While we only measure compression up to 30%, we speculate that if higher compression ratios could be achieved, the compressed Taylor states could form the basis of a new kind of fusion engine. The theoretically predicted magnetohydrodynamic (MHD) and double-adiabatic [Chew-Goldberger-Low (CGL)] EOSs are compared to experimental measurements to estimate the adiabatic nature of the compressed plasma. Since our magnetized plasmas relax to an equilibrium described by MHD, one might expect their thermodynamics to be governed by the corresponding EOS. However, we find that the MHD EOS is not supported by our data. Our results are more consistent with the parallel CGL EOS suggesting that these weakly collisional plasmas have most of their proton energy in the direction parallel to the magnetic field

    Semiclassical triton

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    The symmetric components of the spatial part of SS- and DD- states' wavefunctions for triton (3H)(^{3}H) are investigated utilizing semiclassical expansion (in the powers of \hbar). Analysis of the diagonalized Hamiltonian reveals the existence of two different mass states within the ground state of triton. We have solved the coupled differential equations for the two admixed states 2S1/2^{2}S_{1/2} and 4D1/2^{4}D_{1/2} owing to tensor interactions exploiting classical WKB-theory using phenomenological Feshbach-Pease potentials. The relative probability of the DD-state is found to be in good agreement with the experimentally inferred value (4 - 5 \%)

    Broken Time Reversal Symmetry and Superconducting States in the Cuprates

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    Recently, Kaminski et al. have reported that time reversal symmetry is broken in the pseudogap phase in the high temperature superconducting material Bi_2Sr_2CaCu_2O_{2+\delta} (Bi-2212). Here we examine the role of translationally invariant broken time reversal states on d_{x^2-y^2} superconductors. In particular, we determine the change in the superconducting order parameter structure. We find that the broken time reversal pseudogap state that is consistent with the experiment of Kaminski et al., gives rise to a novel mixed singlet-triplet pairing d+ip phase. This d+ip state is shown to give rise to a helical superconducting phase. Consequences of this d+ip state on Josephson experiments are discussed.Comment: 5 pages, 1 figur

    Appraisal of maize germplasm for identification of nutritionally rich nutraceutical genotypes

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    Thirty maize genotypes were characterized for their nutritional, antinutritional and nutraceutical traits for identification of elite germplasm rich in beneficial characteristics. Starch, proteins, lipids, tryptophan, lysine, β-carotene, condensed tannins, protease inhibitor, phytic acid, total phenols, flavonols, o-dihydroxy phenols and DPPH radical scavenging activity were determined in grains of all the genotypes. Correlation coefficient among the various parameters showed that lysine, total phenols, flavonols and o-dihydroxy phenols were negatively correlated with phytic acid content of the genotypes. This showed that the nutritional and the nutraceutical potency of genotypes, rich in lysine and phenolic compounds, is further propounded by a reduction of phytic acid content in them. On the basis of various constituents, the genotypes were divided into three groups. Group-A genotypes had high to moderate levels of both nutritional and nutraceutical traits. Group-B included those genotypes that exhibited high to moderate levels of either nutritional or nutraceutical traits. Group-C was constituted of genotypes that had lower levels of both nutritional and nutraceutical traits. Agglomerative hierarchical clustering showed that the D subcluster of MC-2 was chiefly comprised of genotypes that had high to moderate levels of both nutritional and nutraceutical traits. It may be concluded that CML134, CML266, TOO14601, LM11, CML264, CML321, SE563, LM10, LM18, LM14 and CML32 were nutritionally rich nutraceutical genotypes having low antinutrient potency

    Further refinements of the Heinz inequality

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    The celebrated Heinz inequality asserts that 2A1/2XB1/2AνXB1ν+A1νXBνAX+XB 2|||A^{1/2}XB^{1/2}|||\leq |||A^{\nu}XB^{1-\nu}+A^{1-\nu}XB^{\nu}|||\leq |||AX+XB||| for XB(H)X \in \mathbb{B}(\mathscr{H}), A,B\in \+, every unitarily invariant norm |||\cdot||| and ν[0,1]\nu \in [0,1]. In this paper, we present several improvement of the Heinz inequality by using the convexity of the function F(ν)=AνXB1ν+A1νXBνF(\nu)=|||A^{\nu}XB^{1-\nu}+A^{1-\nu}XB^{\nu}|||, some integration techniques and various refinements of the Hermite--Hadamard inequality. In the setting of matrices we prove that \begin{eqnarray*} &&\hspace{-0.5cm}\left|\left|\left|A^{\frac{\alpha+\beta}{2}}XB^{1-\frac{\alpha+\beta}{2}}+A^{1-\frac{\alpha+\beta}{2}}XB^{\frac{\alpha+\beta}{2}}\right|\right|\right|\leq\frac{1}{|\beta-\alpha|} \left|\left|\left|\int_{\alpha}^{\beta}\left(A^{\nu}XB^{1-\nu}+A^{1-\nu}XB^{\nu}\right)d\nu\right|\right|\right|\nonumber\\ &&\qquad\qquad\leq \frac{1}{2}\left|\left|\left|A^{\alpha}XB^{1-\alpha}+A^{1-\alpha}XB^{\alpha}+A^{\beta}XB^{1-\beta}+A^{1-\beta}XB^{\beta}\right|\right|\right|\,, \end{eqnarray*} for real numbers α,β\alpha, \beta.Comment: 15 pages, to appear in Linear Algebra Appl. (LAA

    Proactive Scheduling in Cloud Computing

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    Autonomic fault aware scheduling is a feature quite important for cloud computing and it is related to adoption of workload variation. In this context, this paper proposes an fault aware pattern matching autonomic scheduling for cloud computing based on autonomic computing concepts. In order to validate the proposed solution, we performed two experiments one with traditional approach and other other with pattern recognition fault aware approach. The results show the effectiveness of the scheme
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