Hydrometer Analysis :
(1) Take the fine soil from the bottom pan of the sieve set, place it into a beaker, and add 125 mL of the dispersing agent (sodium
hexametaphosphate (40 g/L)) solution. Stir the mixture until the soil is thoroughly wet. Let the soil soak for at least ten minutes.
Fig. 3 reveals the three-dimensional microstructure of the Al-Cu-Mg alloy after mechanical polishing and Keller etching, which demonstrates that this alloy has pancake shaped grains. At this stage, the specimen could not provide clear Kikuchi patterns for EBSD analysis due to the surface residual stress, which is introduced in the mechanical polishing processes. Therefore, the Al-Cu-Mg alloy was slightly electro-polished to remove the surface deformation. Fig. 4a shows the resulting optical micrograph and Fig. 4b shows the grain boundary map of the alloy from EBSD analysis. A comparison of both images demonstrates an obvious difference in grain sizes. As a result, the grain dimensions by EBSD along T and S directions are 109.7 and 47.6 μm respectively, whereas the results measured in optical microscopy are 388.3 and 70.1 μm, which are two to three times the values from EBSD analysis.
The Bonny Island lies in the Niger Delta approximately 40 km South of Port Harcourt, Nigeria. It lies between 4° 52ʺ N to 5° 02ʺ N and longitudes 6° 56ʺ E to 7° 04ʺ E within the beach ridges onshore geomorphic sub-environment of the Niger Delta (Figure 1). The topography of the Island is relatively flat with an elevation of 3.05 atmospheric mean sea level (NLNG, 2005). It has a tropical climate with two distinct seasons, wet (April-October) and dry (November- March). The intricate network of rivers and their discharge patterns result in the formation of several morphological units. Akpokodje et al., (2014) recognized five major geomorphologic units within the Niger Delta. They are: Active and abandoned coastal beaches; Salt water mangrove swamps: Freshwater swamps and meander belt; Sombreiro Warri plain, dry deltaic plain with abundant swamp zones and Dry flat land and plain. Bonny Island lies within the active/abandoned coastal beaches (Fakeye &
Measurement of a sample by the cumulative method can be carried out at little cost in a standard laboratory. Gravitational sedimentation has limited practical value for particles under a few micrometers in diameter due to the prohibitively long settling times (several hours). The experiment can be hastened by increasing accelerating forces through use of a centrifuge. Stokes’ Law is only valid for spheres which are the most-compact shape for the volume or surface area they possess. Most volcanic particles will possess more surface area than a sphere and, therefore, will settle more slowly. Stokes’ Law only applies to gravitational settling and not to particles affected by Brownian motion. For example, particles < 0.5 µm diameter give errors in excess of 100 % unless correction terms are applied. Particles > ~ 50 µm will also settle more slowly than the velocity predicted by Stokes' Law. The upper size limit can be increased by using a suspending fluid with a higher viscosity. The underlying principles for centrifugal sedimentation are largely the same as in the gravitational case, but the calculations and measurement geometry are more complex because the particle velocity increases with distance from the centre of rotation.
A glider is an aircraft that lacks an engine and is heavier than air. In this project, you are an aeronautical engineer who must design and build a glider to travel the greatest distance when launched from a catapult. Engineering a glider requires several steps and lots of responsibility. You must (1) create a preliminary design, (2) construct a glider to experiment with, (3) then run tests where one aspect is changed at a time and its effect is recorded. Once your design is optimized, (4) you will submit a technical report that explains your design, experiments, and analysis. Lastly, (5) you will compete against other teams in a class-wide gliding competition. Each step has specifics that you will have to meet in order to move on to the next step and earn full points. Most materials are available from your teacher and excess should be returned.
had been observed for both micronutrients. Most of these mid-parent heterosis values were in the negative direction, indicating the involvement of genes other than those with additive gene action where alleles determining lower Fe and Zn densities are partially dominant. It is also likely that effects of genes acting additively for Fe and Zn dens- ities are influenced by genetic backgrounds, the more so in the negative direction, mimicking low levels of partial dominance. Iniadi germplasm so far has been found to be the best source of high Fe and Zn density in pearl millet (Velu et al. 2011b; Rai et al. 2012; Govindaraj et al. 2013). Thus, taking into consideration the additive gene action, if the same source is used to introgress the genes respon- sible for Fe and Zn density in both parental lines, it is likely to reduce the genetic diversity between B-lines (and consequently A-lines) and R-lines for other traits. This would potentially lead to reduction in heterosis for grain yield and other traits of agronomic and economic import- ance, which are predominantly under non-additive gene effects. Genomics approaches for selective introgression of genes for Fe and Zn density in the parental lines without disrupting the diversity between them for other traits can play a major role in breeding high-yielding hybrids with higher levels of Fe and Zn densities.
culation (the removed mass fraction is < 1%). The pro- cesses considered are (i) “grain growth”—grain growth by accretion and coagulation in a dense medium, (ii) “shock destruction”—destruction by sputtering in SN shocks, and (iii) “grain disruption”—grain disruption by shattering in interstellar turbulence. Shattering in SN shocks (Jones et al., 1996) could be included as a separate component, but in our framework, it is not possible to separately constrain the contributions from the two shattering mechanisms because both shattering mechanisms (turbulence and SN shocks) se- lectively destroy grains with a 0.03 μm and increase smaller grains, predicting similar grainsize distributions. Thus, we simply assume that the size distribution of shat- tered grains, whatever the shattering mechanism may be, is represented by the one adopted in Subsection 2.1.3.
1.3.3 Calculation of Fractional Components
The fractional components and percentage diameters (D 85 , D 60 ,D 50 , etc.) are computed by creating a
cubic spline model of the particle size distribution curve then solving the model for the curve values at various percentages.
Walgreen et al. (2003) developed a model to study the initial formation of shoreface- connected ridges on storm dominated shelves. Within their model, they considered both bed load and suspended load sediment fluxes to analyze the corresponding grainsize distribution. They found a net stabilizing effect of sediment sorting on the growth of the bedforms. Due to the sediment mixture the growth rates decrease and the migration rates increase. The preferred wavelength becomes longer, although the wavelengths are only slightly affected by the sorting processes. The model shows also grainsize sorting. The coarsest material occurs on the landward (up current) flank and the finer on the seaward (down current) flank of the ridges.
where μ is the chemical potential of the solute atom dissolved in a matrix of solvent atoms. represents the excess amount of solute atoms segregated to the boundary. Plots of γ = dG/dA versus global solute con- centration obtained by Hondros and Seah [ 34 ] show a reduction of γ with increasing solute concentration. This negative trend is intensiﬁed for solute atoms with large atomic size misﬁt. This eﬀect suggests that large non- equilibrium atomic size misﬁt solutes can segregate to grain boundaries and consequently could reduce excess grain boundary free energy with the possible outcome of grainsize stabilization at γ = 0. γ is not to be confused with grain boundary cohesive energy. The concept was developed further in the solution models proposed by Weissmüller,[ 35 , 36 ] Kirchheim and coworkers,[ 37 – 39 ] and Darling et al.[ 40 ] These models are applied in the dilute solution limit. Trelewicz and Schuh [ 41 ] proposed a binary mixing model applicable to non-dilute solutions with ﬁnite grain boundary volume fraction, but they did not include the elastic strain energy enthalpy change due to solute elastic size misﬁt. Saber et al. [ 42 , 43 ] modiﬁed this approach to include elastic enthalpy, and subse- quently extended it to the wider class of ternary alloy systems. In addition to this, nanostructured alloy stability diagrams and atomistic modeling simulations relevant to grain boundary stabilization by alloy addition have been reported.
(2007) and Lizana et al. (2010). Considering the positive rela- tionships between maximum grain water content and maxi- mum grain filling rate, and between grain water absorption rate and the rates of initial and rapid grain filling, it can be deduced that grain water drives the synthesis of storage prod- ucts, serving as a raw material or medium. In addition, grain length reached its maximum just after maximum grain water content. Following this, grain width, height, and volume stopped expanding almost simultaneously, while the grains started to lose water. This implies that grain water may func- tion as an incentive for grain dimension establishment. Once grain desiccation commences, the driving force disappears and grain enlargement ends. Briarty et al. (1979) reported that the endosperm and cell volume reach their maximums at the same time (35 d after anthesis), and the timing is sim- ilar to that for maximum grain water content in this study (31 d), supporting the above hypothesis. Meanwhile, the flag leaves also underwent rapid senescence, indicating synchrony. Around this critical time, rapid reduction in flag leaf and ear photosynthesis (Sofield et al., 1977) and programmed cell death in the entire endosperm of grains (Young and Gallie,
Abstract Sandy shallow seas, like the North Sea, are very dynamic. Several morphological features are present on the bed, from small ripples to sand waves and large tidal sand- banks. The larger patterns induce significant depth variations that have an impact on human activities taking place in this area. Therefore, it is important to know where these large- scale features occur, what their natural behaviour is and how they interact with human activities. Here, we extend earlier research that compares the results of an idealized model of large-scale seabed patterns with data of seabed patterns in the North Sea. The idealized model is extended with a grainsize dependency. The adaptations lead to more accurate predic- tions of the occurrence of large-scale bed forms in the North Sea. Therefore, grainsize dependency and, in particular, critical shear stress are important to explain the occurrence of sand waves and sandbanks in the North Sea.
The main materials used in this experiment were various size of sand and mixture of glass bead and sand with a certain ratio, brine (NaCl solutions) with concentration 20,000 ppm as a displacing fluid and crude oil as a displaced fluid. Meanwhile the equipment that involved was such as shrinkage pump, sand pack holder and measure cylinder. The sand pack holder comprises, a housing forming an open-ended longitudinal bore where fluid may be injected into the sand sample at one end and discharged from the other ports can be readily accessed. The dimension of sand pack holder is 30.5 cm in length and 2.5 cm in diameter. Both sides were equipped with metal sieve that prevents any sand flow.
Four nanostructured ferroelectric ceramics with different grain sizes are established via Voronoi tessellations. The dielectric breakdown strength and ferroelectric hysteresis loop are numerically calculated through a phase-field model and a finite element method based on a classical and modi- fied hyperbolic tangent model, respectively. It is found that as the grainsize decreases, the dielectric strength is enhanced, but the dielectric permittivity is reduced. Under the same applied electric field, the ferroelectric ceramic with the smal- ler grainsize possesses a lower discharge energy density but higher energy storage efficiency. When the applied electric field reaches their own breakdown strength, the smallest grain-sized ceramic displays the largest discharge energy density and energy storage efficiency. It is highly suggested that ferroelectric ceramics with smaller grain sizes can be used for applications in energy storage devices.
The algorithm for reconstruction consisted first, of extruding the grain projection from each binary image along a constant depth to form a cylinder with the cross section defined by the grain projection, for computational reasons the depth was taken as the largest dimension of the grain. The 3D grain was obtained from finding the intersection of all the N cylinders rotated by the cumulative angle of (i-1)×θ according with the schematics shown in Figure 3. The optimal angle of rotation (θ) and number of projections needed to accurately capture the 3D outline was investigated and reported by authers previously. It was shown that 6 projections can reperesent the shape with 95% accuracy in terms of measured volume. The measured volume equaled the real volume when the number of projections is 25. Thus, 25 projections were used in this study.
The area of sand dunes is 58998.4 ha. This series is located in central of Iran in Yazd and Esfehan province in longitudes 54º 15' to 55º 20' E and latitudes 32º 30' to 33º 40' N. There are barchans, seif & goord dune in this erg. The goord dunes are located in the end of erg and their heights are to 80 m. The mean grain sizes vary between 600 µ and <62 µ with a mean of 146µ. The mean value of skewness is 2.31 indicating that the irregular fine sediments are more than the others. Mod of this grain is 150 µ. Also, based on shape of sand grain surveys, the abrasion coefficient is 388 that show the abrasion is medium. Study of sediments showed, 0% particles have chemical and physical erosion, 32 % have water erosion and 68 % have wind erosion.
Sediment loads with larger median grain sizes create deltas with more channel mouths (Figures 7c and 11). Channels on a delta can be created by three processes: (1) bifurcation around river mouth bars, (2) bifurcation around braid bars initiated within the channel rather than at the channel mouth, and (3) avulsion to new locations and creation of crevasse channels. Channel avulsion and crevassing is typically associated with aggrading river systems [Slingerland and Smith, 2004] because the aggradation perches the channel above the floodplain, creating a gravitationally unstable channel that will seek the steeper and lower path in the adjacent floodplain. I suggest that the higher aggradation rates on coarse-grained deltas (as inferred from Figure 17 and from the higher elevations at the delta apex in Figure 5) create frequently avulsing channels with morphologies similar to crevasse channels.
The occurrence of weeds, pests and diseases is recorded, and the results are described. Since the results are only from the two first years of the experiments, it is not possible to conclude anything about the crop rotations as such. There are however differences related to the other experimental treatments in the experiment: the presence or absence of catch crops and manure. Only in very few cases are the differences statistically significant.
The first term on the right side of (5) accounts for radiative, relativistic, and recoil e ﬀ ects, while the first term on the right side of (6) is the Fermi energy arising from the interaction between the muon and the proton magnetic moment and diﬀerent corrections to it. It is also important, that like for the problem of the anomalous magnetic moments of leptons [4, 5], the coeﬃcients in front of the radius terms in (5), (6) are much stronger enhanced for the muonic system relative to the electronic system, and thus much more sensitive in extraction of the radii parameters from the experimental data.
Carrying amount, 12/31/12 2,195,000
PROBLEM NO. 9 – Analysis of investments in debt instrument (HTM)
On June 1, 2014, Panday Corporation purchased as a long term investment 6,000 of the P1,000 face value, 8% bonds of Pira Corporation. Panday Corporation has the positive intention and ability to hold these bonds to maturity. The bonds were purchased to yield 10% interest. Interest is payable semi-annually on December 1 and June 1. The bonds mature on June 1, 2020. On November 1,2015, Panday Corporation sold the bonds for a total consideration of P5,887,500. REQUIRED: