1,054 research outputs found

    Crop response to liquid swine effluent and solid cattle manure over four years in east-central Saskatchewan

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    Non-Peer ReviewedDue to the advent of relatively cheap chemical N fertilizers, the use of livestock manure as a source of nutrients to crops was downplayed (James, et al., 1996). However, the expansion of the livestock industry, the need to utilize of the manure in an environmentally friendly and economically viable manner, and the desire to minimize the use of chemical N fertilizers have rekindled interest in the use of livestock manure as a fertilizer. Of particular interest is the need to utilize manure from large-scale intensive livestock operations (Chang and Janzen, 1996). This report is part of an on-going study initiated in 1996 to examine the soil and crop response to application of liquid swine manure and solid feedlot cattle manure at different rates and methods of application. Furthermore, the study seeks to evaluate nutrient forms and amounts in the manure and the effect of rate and method of manure application on soil fertility, nutrient utilization and crop yield. This paper puts together and summarizes the results of crop response to annual application of the two types of manure compared to that of urea fertilizer observed over the past four years, 1997 to 2000

    R-parity violation effect on the top-quark pair production at linear colliders

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    We investigate in detail the effects of the R-parity lepton number violation in the minimal supersymmetric standard model (MSSM) on the top-quark pair production via both ee+e^--e^+ and γγ\gamma-\gamma collision modes at the linear colliders. We find that with the present experimental constrained /R\rlap/{R} parameters, the effect from /R\rlap/{R} interactions on the processes e+ettˉe^+e^-\to t\bar{t} and e+eγγttˉe^+e^- \to \gamma\gamma \to t\bar{t} could be significant and may reach -30% and several percent, respectively. Our results show that the /R\rlap/{R} effects are sensitive to the c.m.s. energy and the relevant /R\rlap/{R} parameters. However, they are not sensitive to squark and slepton masses when mq~400GeVm_{\tilde{q}} \geq 400 GeV (or ml~300GeVm_{\tilde{l}} \geq 300 GeV) and are almost independent on the tanβ\tan\betaComment: Accepted by Phys.Rev.

    Sturmian morphisms, the braid group B_4, Christoffel words and bases of F_2

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    We give a presentation by generators and relations of a certain monoid generating a subgroup of index two in the group Aut(F_2) of automorphisms of the rank two free group F_2 and show that it can be realized as a monoid in the group B_4 of braids on four strings. In the second part we use Christoffel words to construct an explicit basis of F_2 lifting any given basis of the free abelian group Z^2. We further give an algorithm allowing to decide whether two elements of F_2 form a basis or not. We also show that, under suitable conditions, a basis has a unique conjugate consisting of two palindromes.Comment: 25 pages, 4 figure

    Effect of mass transport on the electrochemical oxidation of alcohols over electrodeposited film and carbon-supported pt electrodes

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    © 2018 The Author(s) Electrochemical oxidation of four different alcohol molecules (methanol, ethanol, n-butanol and 2-butanol) at electrodeposited Pt film and carbon-supported Pt catalyst film electrodes, as well as the effect of mass transport on the oxidation reaction, has been studied systematically using the rotating disk electrode (RDE) technique. It was shown that oxidation current decreased with an increase in the rotation rate (ω) for all alcohols studied over electrodeposited Pt film electrodes. In contrast, the oxidation current was found to increase with an increase in the ω for Pt/C in ethanol and n-butanol-containing solutions. The decrease was found to be nearly reversible for ethanol and n-butanol at the electrodeposited Pt film electrode ruling out the possibility of intermediate CO ads poisoning being the sole cause of the decrease and was attributed to the formation of soluble intermediate species which diffuse away from the electrode at higher ω. In contrast, an increase in the current with an increase in ω for the carbon supported catalyst may suggest that the increase in residence time of the soluble species within the catalyst layer, results in further oxidation of these species. Furthermore, the reversibility of the peak current on decreasing the ω could indicate that the surface state has not significantly changed due to the sluggish reaction kinetics of ethanol and n-butanol

    Blow up criterion for compressible nematic liquid crystal flows in dimension three

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    In this paper, we consider the short time strong solution to a simplified hydrodynamic flow modeling the compressible, nematic liquid crystal materials in dimension three. We establish a criterion for possible breakdown of such solutions at finite time in terms of the temporal integral of both the maximum norm of the deformation tensor of velocity gradient and the square of maximum norm of gradient of liquid crystal director field.Comment: 22 page

    ABJM with Flavors and FQHE

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    We add fundamental matters to the N=6 Chern-Simons theory (ABJM theory), and show that D6-branes wrapped over AdS_4 x S^3/Z_2 in type IIA superstring theory on AdS_4 x CP^3 give its dual description with N=3 supersymmetry. We confirm this by the arguments based on R-symmetry, supersymmetry, and brane configuration of ABJM theory. We also analyze the fluctuations of the D6-brane and compute the conformal dimensions of dual operators. In the presence of fractional branes, the ABJM theory can model the fractional quantum Hall effect (FQHE), with RR-fields regarded as the external electric-magnetic field. We show that an addition of the flavor D6-brane describes a class of fractional quantum Hall plateau transition.Comment: 23 pages, Latex, no figures; (v2) references added, typos correcte

    Stability and Decay Rates of Non-Isotropic Attractive Bose-Einstein Condensates

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    Non-Isotropic Attractive Bose-Einstein condensates are investigated with Newton and inverse Arnoldi methods. The stationary solutions of the Gross-Pitaevskii equation and their linear stability are computed. Bifurcation diagrams are calculated and used to find the condensate decay rates corresponding to macroscopic quantum tunneling, two-three body inelastic collisions and thermally induced collapse. Isotropic and non-isotropic condensates are compared. The effect of anisotropy on the bifurcation diagram and the decay rates is discussed. Spontaneous isotropization of the condensates is found to occur. The influence of isotropization on the decay rates is characterized near the critical point.Comment: revtex4, 11 figures, 2 tables. Submitted to Phys. Rev.

    Hidden Order in the Cuprates

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    We propose that the enigmatic pseudogap phase of cuprate superconductors is characterized by a hidden broken symmetry of d(x^2-y^2)-type. The transition to this state is rounded by disorder, but in the limit that the disorder is made sufficiently small, the pseudogap crossover should reveal itself to be such a transition. The ordered state breaks time-reversal, translational, and rotational symmetries, but it is invariant under the combination of any two. We discuss these ideas in the context of ten specific experimental properties of the cuprates, and make several predictions, including the existence of an as-yet undetected metal-metal transition under the superconducting dome.Comment: 12 pages of RevTeX, 9 eps figure
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