63,409 research outputs found
Changes of Physico–Chemical Properties of Pig Slurry During Storage
This study was aimed to determine changes of the characteristics of raw pig slurry as liquid organic fertilizer at various storage times. A completely randomized design was used in this research. The treatments were storage times, i.e.: 0, 15, 30, 45, and 60 days. Variables observed were loss of the slurry, degree of acidity (pH), electrical conductivity (EC), total solid (TS), volatile solid (VS), total chemical oxygen demand (tCOD), soluble chemical oxygen demand (sCOD), total nitrogen (TN), ammonia-nitrogen (NH3-N), nitrate-nitrogen (NO3-N), total phosphate (TP), and dissolve reactive phosphate (DRP). The results showed that storage time significantly affected all the observed variables, except the concentration of NO3-N and total phosphate content. The pH, TS, VS, DRP, and losses of slurry lost during storage times increased, while EC, TN, NH3-N, tCOD, and sCOD decreased. Physico-chemical properties of slurry during storage times changed, as a result of organic matter breakdown
The effect of silicon on the glass forming ability of the Cu47Ti34Zr11Ni8 bulk metallic glass forming alloy during processing of composites
Composites of the Cu47Ti34Zr11Ni8 bulk metallic glass, reinforced with up to 30 vol % SiC particles are synthesized and characterized. Results based on x-ray diffraction, optical microscopy, scanning Auger microscopy, and differential scanning calorimetry (DSC) are presented. During processing of the composites, a TiC layer forms around the SiC particles and Si diffuses into the Cu47Ti34Zr11Ni8 matrix stabilizing the supercooled liquid against crystallization. The small Si addition between 0.5 and 1 at. % increases the attainable maximum thickness of glassy ingots from 4 mm for Cu–Ti–Zr–Ni alloys to 7 mm for Cu–Ti–Zr–Ni–Si alloys. DSC analyses show that neither the thermodynamics nor the kinetics of the alloy are affected significantly by the Si addition. This suggests that Si enhances the glass forming ability by chemically passivating impurities such as oxygen and carbon that cause heterogeneous nucleation in the melt
Mechanical properties of Zr_(57)Nb_5Al_(10)Cu_(15.4)Ni_(12.6) metallic glass matrix particulate composites
To increase the toughness of a metallic glass with the nominal composition Zr_(57)Nb_5Al_(10)Cu_(15.4)Ni_(12.6), it was used as the matrix in particulate composites reinforced with W, WC, Ta, and SiC. The composites were tested in compression and tension experiments. Compressive strain to failure increased by more than 300% compared with the unreinforced Zr_(57)Nb_5Al_(10)Cu_(15.4)Ni_(12.6), and energy to break of the tensile samples increased by more than 50%. The increase in toughness came from the particles restricting shear band propagation, promoting the generation of multiple shear bands and additional fracture surface area. There was direct evidence of viscous flow of the metallic glass matrix within the confines of the shear bands
Reply to "Comment on `First-principles calculation of the superconducting transition in MgB2 within the anisotropic Eliashberg formalism'"
The recent preprint by Mazin et al. [cond-mat/0212417] contains many
inappropriate evaluations and/or criticisms on our published work [Phys. Rev. B
66, 020513 (2002) and Nature 418, 758 (2002)]. The preprint
[cond-mat/0212417v1] was submitted to Physical Review B as a comment on one of
our papers [Phys. Rev. B 66, 020513 (2002)]. In the reviewing process, Mazin et
al. have withdrawn many of the statements contained in cond-mat/0212417v1,
however two claims remain in their revised manuscript [cond-mat/0212417v3]: (1)
the calculated variations of the superconducting energy gap within the sigma-
or the pi-bands are not observable in real samples due to scatterings, and (2)
the Coulomb repulsion mu(k,k') is negligibly small between sigma- and pi-states
and thus should be approximated by a diagonal 2 x 2 matrix in the sigma and pi
channels. Here, we point out that the former does not affect the validity of
our theoretical work which is for the clean limit, and that the latter is not
correct
Comment about pion electro-production and the axial form factors
The claim by Haberzettl (Phys.Rev.Lett.85 (2000) 3576) that the axial form
factor of the nucleon cannot be accessed through threshold pion
electroproduction is unfounded
Gauge Theories in and Fine-Lattice Deconstruction
The logarithmic energy dependence of gauge couplings in AdS_5 emerges almost
automatically when the theory is deconstructed on a coarse lattice. Here we
study the theory away from the coarse-lattice limit. While we cannot
analytically calculate individual KK masses for a fine lattice, we can
calculate the product of all non-zero masses. This allows us to write down the
gauge coupling at low energies for any lattice-spacing and curvature. As
expected, the leading log behaviour is corrected by power-law contributions,
suppressed by the curvature. We then turn to intermediate energies, and discuss
the gauge coupling and the gauge boson profile in perturbation theory around
the coarse-lattice limit.Comment: 17 pages, 1 figure, typos in listing version of abstract correcte
Warped product approach to universe with non-smooth scale factor
In the framework of Lorentzian warped products, we study the
Friedmann-Robertson-Walker cosmological model to investigate non-smooth
curvatures associated with multiple discontinuities involved in the evolution
of the universe. In particular we analyze non-smooth features of the spatially
flat Friedmann-Robertson-Walker universe by introducing double discontinuities
occurred at the radiation-matter and matter-lambda phase transitions in
astrophysical phenomenology.Comment: 10 page
Deconstruction and Gauge Theories in AdS_5
On a slice of AdS_5, despite having a dimensionful coupling, gauge theories
can exhibit logarithmic dependence on scale. In this paper, we utilize
deconstruction to analyze the scaling behavior of the theory, both above and
below the AdS curvature scale, and shed light on position-dependent
regularizations of the theory. We comment on applications to geometries other
than AdS.Comment: 15 pages, 1 figur
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