5,846 research outputs found

    Pertanggungjawaban Korporasi dalam Tindak Pidana Korupsi Pengadaan Barang dan Jasa Pemerintah di Bidang Konstruksi

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    Offenses of corruption and crime that often occurs in the procurement of goods/services that are common construction in accordance with Act No. 31 of 1999 such is: a crime against the state financial harm to the law or abuse of power, bribery offense group, group evasion offense in the post, extortion offense in office, deeds offense, offense relating to an interest in the procurement, and gratification. That the Corporation could be required for Corporate Responsibilities when the corruption in the procurement of goods and services in the field of construction that we can see at verdict No. 04/Pid. Sus/2011/PT. BJM which have permanent legal force (inkrachtvan gewische). The above findings generated through normative research methods to approach the analysis of legal materials, either primary, ie Act No. 31 of 1999 jo . Act No. 20 of 2001 on Eradication of Corruption, secondary legal materials, and tertiary legal materials

    Velocity fluctuations and hydrodynamic diffusion in sedimentation

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    We study non-equilibrium velocity fluctuations in a model for the sedimentation of non-Brownian particles experiencing long-range hydrodynamic interactions. The complex behavior of these fluctuations, the outcome of the collective dynamics of the particles, exhibits many of the features observed in sedimentation experiments. In addition, our model predicts a final relaxation to an anisotropic (hydrodynamic) diffusive state that could be observed in experiments performed over longer time ranges.Comment: 7 pages, 5 EPS figures, EPL styl

    Direct numerical simulations for non-Newtonian rheology of concentrated particle dispersions

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    The non-Newtonian behavior of a monodisperse concentrated dispersion of spherical particles was investigated using a direct numerical simulation method, that takes into account hydrodynamic interactions and thermal fluctuations accurately. Simulations were performed under steady shear flow with periodic boundary conditions in the three directions. The apparent shear viscosity of the dispersions was calculated at volume fractions ranging from 0.31 to 0.56. Shear-thinning behavior was clearly observed at high volume fractions. The low- and high-limiting viscosities were then estimated from the apparent viscosity by fitting these data into a semi-empirical formula. Furthermore, the short-time motions were examined for Brownian particles fluctuating in concentrated dispersions, for which the fluid inertia plays an important role. The mean square displacement was monitored in the vorticity direction at several different Peclet numbers and volume fractions so that the particle diffusion coefficient is determined from the long-time behavior of the mean square displacement. Finally, the relationship between the non-Newtonian viscosity of the dispersions and the structural relaxation of the dispersed Brownian particles is examined

    A Simulation Method to Resolve Hydrodynamic Interactions in Colloidal Dispersions

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    A new computational method is presented to resolve hydrodynamic interactions acting on solid particles immersed in incompressible host fluids. In this method, boundaries between solid particles and host fluids are replaced with a continuous interface by assuming a smoothed profile. This enabled us to calculate hydrodynamic interactions both efficiently and accurately, without neglecting many-body interactions. The validity of the method was tested by calculating the drag force acting on a single cylindrical rod moving in an incompressible Newtonian fluid. This method was then applied in order to simulate sedimentation process of colloidal dispersions.Comment: 7pages, 7 figure

    Effect of Salt Concentration on the Electrophoretic Speed of a Polyelectrolyte through a Nanopore

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    In a previous paper [S. Ghosal, Phys. Rev. E 74, 041901 (2006)] a hydrodynamic model for determining the electrophoretic speed of a polyelectrolyte through an axially symmetric slowly varying nanopore was presented in the limit of a vanishingly small Debye length. Here the case of a finite Debye layer thickness is considered while restricting the pore geometry to that of a cylinder of length much larger than the diameter. Further, the possibility of a uniform surface charge on the walls of the nanopore is taken into account. It is thereby shown that the calculated transit times are consistent with recent measurements in silicon nanopores.Comment: 4 pages, 2 figure

    Determination of the zeta potential for highly charged colloidal suspensions

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    We compute the electrostatic potential at the surface, or zeta potential ζ\zeta, of a charged particle embedded in a colloidal suspension using a hybrid mesoscopic model. We show that for weakly perturbing electric fields, the value of ζ\zeta obtained at steady state during electrophoresis is statistically indistinguishable from ζ\zeta in thermodynamic equilibrium. We quantify the effect of counterions concentration on ζ\zeta. We also evaluate the relevance of the lattice resolution for the calculation of ζ\zeta and discuss how to identify the effective electrostatic radius.Comment: 8 pages, 3 figures with 2 panel

    Electrophoresis of colloidal dispersions in the low-salt regime

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    We study the electrophoretic mobility of spherical charged colloids in a low-salt suspension as a function of the colloidal concentration. Using an effective particle charge and a reduced screening parameter, we map the data for systems with different particle charges and sizes, including numerical simulation data with full electrostatics and hydrodynamics and experimental data for latex dispersions, on a single master curve. We observe two different volume fraction-dependent regimes for the electrophoretic mobility that can be explained in terms of the static properties of the ionic double layer.Comment: Substantially revised versio

    Time of harvesting soybeans : in relation to soil improvement and protein content of the hay

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    Cover title.Includes bibliographical references

    Systematic characterization of thermodynamic and dynamical phase behavior in systems with short-ranged attraction

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    In this paper we demonstrate the feasibility and utility of an augmented version of the Gibbs ensemble Monte Carlo method for computing the phase behavior of systems with strong, extremely short-ranged attractions. For generic potential shapes, this approach allows for the investigation of narrower attractive widths than those previously reported. Direct comparison to previous self-consistent Ornstein-Zernike approximation calculations are made. A preliminary investigation of out-of-equilibrium behavior is also performed. Our results suggest that the recent observations of stable cluster phases in systems without long-ranged repulsions are intimately related to gas-crystal and metastable gas-liquid phase separation.Comment: 10 pages, 8 figure
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