Boundary stripping

Critchley CNR, Fowbert J A and Sherwood A J (2006). The effects of annual cultivation on plant community composition of uncropped arable field boundary strips . Agriculture, Ecosystems and Environment, 113, 196-205. 

T. Horibe, Boundary Strip Method for Large Deflection Analysis of Elastic Rectangular Plates, Transaaion of the Japan Society of Mechanical Engineers, 56(532) (1990) 140 (Japanese). 

All boundary strips dividing the land holdings of the members of the artels [collective farms] shall be abolished and all plots of land thrown into one Itirge area of land to be used collectively by the artel... 

Demonstrations (a) Atomix (to show grain boundaries), (b) Model of dispersion strengthening. Take piece of PMMA sheet == 2.5 mm thick and = 7 cm square. Glue four PMMA strips of section =7X7 mm on top of the sheet to form a tray = 7 mm deep. Cut six = 7-mm lengths of an = 6-mm-diameter PMMA rod. Glue the ends of these to... 

For the extension to two dimensions we consider a square lattice with nearest-neighbor interactions on a strip with sites in one direction and M sites in the second so that, with cyclic boundary conditions in the second dimension as well, we get a toroidal lattice with of microstates. The occupation numbers at site i in the 1-D case now become a set = ( ,i, /25 5 /m) of occupation numbers of M sites along the second dimension, and the transfer matrix elements are generalized to... 

To carry out a numerical solution, a single strip of quadrilateral elements is placed along the x-axis, and all nodal temperatures are set Initially to zero. The right-hand boundary is then subjected to a step Increase in temperature (T(H,t) - 1.0), and we seek to compute the transient temperature variation T(x,t). The flow code accomplishes this by means of an unconditionally stable time-stepping algorithm derived from "theta" finite differences a solution of ten time steps required 22 seconds on a PC/AT-compatible microcomputer operating at 6 MHz. 

Several boundary conditions have been used to prescribe the outer limit of an individual rhizosphere, (/ = / /,). For low root densities, it has been assumed that each rhizosphere extends over an infinite volume of. soil in the model //, is. set sufficiently large that the soil concentration at r, is never altered by the activity in the rhizosphere. The majority of models assume that the outer limit is approximated by a fixed value that is calculated as a function of the maximum root density found in the simulation, under the assumption that the roots are uniformly distributed in the soil volume. Each root can then extract nutrients only from this finite. soil cylinder. Hoffland (31) recognized that the outer limit would vary as more roots were formed within the simulated soil volume and periodically recalculated / /, from the current root density. This recalculation thus resulted in existing roots having a reduced //,. New roots were assumed to be formed in soil with an initial solute concentration equal to the average concentration present in the cylindrical shells stripped away from the existing roots. The effective boundary equation for all such assumptions is the same ... 

In order to develop more informative and direct method of studying the spillover effect of active particles, the authors of [37] suggested to use the sensor method of detecting migrating particles based on separation of sensor and emitter (donor) of active particles. The latter consists of small metal globules, or clusters (with a diameter of about 20-30 A) of Pt, Pd, Ni, etc. (activator) deposited on quartz or sapphire (AI2O3) plate in the form of a strip less than 1 cm wide. The sensor for detection of hydrogen atoms consisted of a zinc oxide strip (with a width of about 0.1 cm and thickness wlOO nm) deposited on the same plate at a distance of 0.03 or 0.6 cm (two versions) from the inner boundaries of activator strips [38]. 

The rectifying or stripping section of a column must operate somewhere between total reflux and minimum reflux conditions. The range of feasible operation of a column section can thus be defined for a given product composition. It can be seen in Figure 12.19 that these section profiles are bounded for a stage column by the distillation line and the pinch point curve. As noted previously, the pinch point curve provides a minimum reflux boundary for both staged and packed columns,... 

When velocity gradients are small, for example, near the boundary layer separation point and at the rear of a cylinder in separated flow, Eq. (33) is inaccurate. The separation point was determined with an accuracy of 1 degree by using twin strip electrodes of 125 /im length, separated by... 

Fig. 5.19. Evolutionary track in the HR diagram of an AGB model of total mass 0.6 Mq, initial composition (Y, Z) = (0.25, 0.001 Z /20). Heavy dots marked 2 to 11 indicate the start of a series of thermal pulses (see Fig. 5.20), which lead to excursions along the steep diagonal lines. Numbers along the horizontal and descending track indicate times in years relative to the moment when an ionized planetary nebula appears and (in parentheses) the mass of the envelope in units of Mq. R = 0.0285 indicates a line of constant radius (R in solar units) corresponding to the white-dwarf sequence. Shaded areas represent earlier evolutionary stages for stars with initial masses 3,5 and 7 Mq and the steep broken line marks the high-temperature boundary of the instability strip in which stars pulsate in their fundamental mode. The y-axis gives log L/Lq. Adapted from Iben and Renzini (1983).

As described previously, in the atomization sub-model, 232 droplet parcels are injected with a size equal to the nozzle exit diameter. The subsequent breakups of the parcels and the resultant droplets are calculated with a breakup model that assumes that droplet breakup times and sizes are proportional to wave growth rates and wavelengths obtained from the liquid jet stability analysis. Other breakup mechanisms considered in the sub-model include the Kelvin-Helmholtz instability, Rayleigh-Taylor instability, 206 and boundary layer stripping mechanisms. The TAB model 310 is also included for modeling liquid breakup. 

The working cathode also generates a boundary layer. The water that is reduced at the cathode is supplied by the bulk catholyte. This stripping effect forms a layer of approximately 37 wt.% caustic on the surface of the cathode. Again, the thickness of this layer is determined by the efficiency of the internal mixing within the cathode compartment. 

Fig. 16.2. Proposed model for the reconstructed Au(lll) surface. Top hard-wall corrugation functions at three points in the unit cell. In each period, two strips should exist as the two boundaries of fee stacking and hep stacking. Bottom proposed structure. Crosses represent the second-layer and circles the surface-layer atoms. (Reproduced from Marten et al., 1985, with permission.)...

The mechanism of transport of GPG using SLM has been studied at the authors laboratory [56]. GPG could be permeated from alkaUne feed of carbonate buffer into an acidic stripping solution of acetate buffer across the membrane comprising Aliquat-336 in -butyl acetate immobiUzed in a polypropylene (Gelgard 2400) support. The transport mechanism is a case of counter transport exhibiting overall rate dependence on solute diffusion in the membrane phase as well as the mass transfer across the aqueous boundary films. 

Boundary layer stripping and possible evaporation of the fuel. 

The molecular theory of surface tension was dealt with by Laplace (1749-1827). But, as a result of the clarification of the nature, of intermolecular forces by quantum mechanics and of the more recent developments in the study of molecular distribution in liquids, the nature and value of surface tension have been better understood from a molecular viewpoint. Surface tension is closely associated with a sudden, but continuous change in the density from the value for bulk liquid to the value for die gaseous state in traversing the surface. See Fig. 2. As a result of this inhomogeneity, the stress across a strip parallel to the boundary—pu per unit area—is different from that across a strip perpendicular to die boundary—pr per unit area. This is in contrast with die case of homogeneous fluid in which the stress across any elementary plane has the same value regardless of the direction of die plane,... 

The authors first mentioned investigated an anion-exchange membrane consisting of polyethylene imine crosslinked with epichlorohydrin in equilibrium with KC1 solutions. The concentration of Cl- ions and K+ ions in the membrane were determined analytically. The mobility of the Cl- ions in the membrane was determined according to the principle of the moving boundary. Thus in a membrane strip a sharp boundary is formed between the OH- and Cl- ions. This boundary will move under the influence of an electric field. This may be made visible with the aid of an indicator. The speed of the boundary is determined by the slowest ion, by consequence the Cl- ion in this instance. 

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