The effects of rolling resistance on the stress-strain and strain localization behavior of granular materials due to simple shear loading conditions.

The previous studies has conclusively shown that rolling resistance is a significant parameter influencing the stress-strain and strain localization response of granular materials when a failure state can be reached in biaxial test with small strain, (2-4%) of axial strain [1, 2]. However, in order to allow for larger deformations, numerical experiments are carried out for a simple shear test. In these simulations strain localization can be obtained for relatively high shear strain. The main objective of this paper is to present the results of a comprehensive study using DEM modeling of the effects of the variation in rolling resistance on the elasticity, shear strength, dilation and bifurcation response of granular materials subjected to simple shear loading. A comprehensive parametric study is performed whereby the magnitude of rolling resistance is varied within its full range of possible values in conjunction with variations in other model parameters, and more practically to interpret the macroscopic behavior of granular specimens subjected to different loading conditions from the viewpoint of micromechanics

Forage Production and Utilization Systems for Cow-calf Beef Production

Native grasslands in South Dakota are extremely variable and have steadily declined in condition. Pasture techniques are currently available to modify vegetation composition and productivity to bring about higher yields. Development of pasture systems that increase forage production is of a major importance in South Dakota. Fransen found that tame pastures and interseeded native range produced more gain per hectare than native range. The average daily gain of the cattle dropped severely at the end of the season in native and native-interseeded range. However, the tame pastures required substantial inputs in terms of fertilizer nitrogen. The purpose of this study was to find a combination of tame and native or tame and native-interseeded pastures that would maintain the average daily gain of the cattle. A second objective was to try to reduce the fertilizer inputs on tame pastures by seeding the tame pastures with alfalfa. South Dakota studies over a 3-year period with native and native interseeded range were encouraging. Vigil pointed out that in native interseeded range, animal gain and carrying capacity increased by 51 and 60 percent, respectively, over non-interseeded ranges. In South Dakota, it is an acceptable practice to renovate pasture lands through interseeding. This method does not require prior seedbed preparation. Native range in South Dakota has produced an average of 2.16 animal unit months (AUM) of grazing per hectare, while a mixture of smooth bromegrass-intermediate wheatgrass and “Teton alfalfa produced 3.25 AUM of grazing; and a series of four seasonal tame grass pastures produced a significant increase in animal production over native range. Shane, after reviewing several pasture systems, concluded that the most economically feasible system was native range followed by short and full season tame series

Flexural performance of built-up cold-formed steel beam filled with compacted soil

Cold-formed steel is the well-liked structural materials in the construction industry and used as an alternative construction material upon the traditional material such as reinforced concrete, hot-rolled steel or timber. The purpose of compacted soil is filled into a cold formed steel section to contribute to the environmentally friendly with reasonable strength and can also reduce production costs without concrete beams. The cold-formed steel material is selected and combined with the compacted soil to construct the beam that could increase the ultimate moment. Compacted soil from the Kaolinite group is prepared and tested to find out its properties. Two cold-formed steel channels are connected face to face to form a built-up box section, tightened with bolts and nuts. Three different bolt spacing arrangements are prepared. The main purpose of the study is to determine the ultimate load of the beam with and without compacted soil, as well as to investigate the relationship of the bolt spacing arrangement to ultimate load resistance. From the result, built-up CFS beam with compacted soil (CFSBCS) showed higher values of the ultimate moment compared to built-up CFS beam without compacted soil (CFSB). Bolt arrangement in the middle spacing influenced the overall ultimate load resistance of the beam. The ultimate load resistance reduced when the length subtraction between bolt arrangement, B and C is less. It is concluded that CFSBCS is able to achieve reasonable ultimate moment and also able to increase initial stiffness

Toward Formulation a Maturity Framework for E-diplomacy

Digital diplomacy (e-Diplomacy), is commonly defined as the use of information and communication technology for the purposes of attaining foreign policy goals. The emerging field of digital diplomacy has been largely neglected in academic research. Also, in practice, this area has been slow to evolve compared to other areas of public service such as e-government, e-education and e-health. This research draws on the existing literature to present a novel conceptual framework that could be used to guide the implementation of e-diplomacy. A new e-diplomacy maturity framework is formulated to address the modern functions of foreign relations in today’s global environment. The e-diplomacy maturity framework is derived from the theory of growth models, the e-government maturity model, the broader literature on diplomacy and the practice of diplomacy. To validate the conceptual framework, a qualitative approach involving semi-structured interviews with diplomats and professionals from the foreign ministries of the USA, the UK and Qatar were conducted. The novelty of this research is based on the development of a conceptual framework of e-diplomacy maturity and implementation that was built around the scaffolding of conjectures that were tested to determine their validity. It can guide research scholars wishing to explore the discipline of digital diplomacy. It will also assist foreign ministries to identify the stage they have reached in deploying ICT in their diplomatic functions. This study should also provide policy makers, diplomats, ICT managers, and practitioners with a greater understanding of the stages and factors that encourage or hinder e-diplomacy implementation and maturity

Exploring Sheraoh Island at South-Eastern Qatar: First Distributional Records of Some Inland and Offshore Biota with Annotated Checklist

Sheraoh island is the most remote among Qatari islands, nearly 73.5 km south-eastern of the mainland of the peninsula. In March 2010, a preliminary general survey of the species was conducted. Observations were made partly by wading and snorkeling in the intertidal zone and partly by surveying the inland habitats. In total the 31 species were recorded, 4 species of halophyte plants: Halopeplis perfoliata, Suaeda vermiculata, Salsola baryosoma and Zygophyllum qatarense, one unexpected terrestrial mammal: the cape hare Lepus capensis, 2 species of visiting birds: Motacilla flava and Anthus campestus and one species of sea bird. Phalacrocorax nigrogularis, one dolphin species: Sousa chinensis. The largest richness was found in the marine habitats, 3 species of sea weeds: Colpomenia sinusa, Padina boergesenii and Sargassum boveanum, 3 species of corals: Anomastraea irregularis, Platygyra lamellina and Porites harrisoni, 2 species of nudibranchs: Chromodoris cazae and Chromodoris sp. (unidentified)., 4 crab species: Hermit crab (unidentified), Etisus laevimanus, Grapsus albolineatus and Lambrus prensor, 4 species of echinoderms: Pentacentral mammillatus, Ophiothela venusta, Diadema setosum and Echinometra mathaei, 5 species of bony fish: Doryrhamphus sp. (larva), Cypserulus oligolepis, Lethrinus nebulosus, Cephalopholis miniatus and Hemiramphus marginatus, one species of sea snakes: Hydrophis sp. The most striking result is to collect an unknown nudibranch species and to report the cape hare which is unexpected inhabitant. All figures of this study are published for the first time in Qatar.Qatar Universit

Spectrophotometric Complex formation Study of Murexide with Nickel and Cobalt in Aqueous Solution

In the present study, the formation constant and the stoichiometry of murexide complexes with Co (II) and Ni (II) have been determined spectrophotometrically in aqueous solution at 25oC. Two experimental parameters governed the complex formation, pH and time, have been investigated. The formation and stoichiometry constants have been determined by two methods: Job's and mole ratio's methods. The absorption maxima for Co-murexide and Ni-murexide complexes were: 480, 460 nm, respectively. The two Spectrophotometric methods confirm the formation of 2:1 (M:L) complexes with stability arrange of: Co > Ni. The formation constants (Kf) determined by the Job's method were as follows: 2.06x1014 and 1.21x1011 for Co-murexide and Ni-murexide, respectively. Also, using mole ratio's method, the formation constants were found to be:  9.18x1011 and 6.01x1011. Molar absorptivity values of the studied complexes have also been determined (by Job's and mole ratio's methods) and the average values were: 18235 and 13284 l/mol.cm for Co and Ni, respectively

Degradabilnost normalnih alkana za vreme ex situ prirodne bioremedijacije zemljišta zagađenog mazutom

It is well known that during biodegradation of oil under natural geological conditions, or oil pollutants in the environment, degradation of hydrocarbons occurs according to a well-defined sequence. For example, the major changes during the degradation process of n-alkanes occur in the second, slight and third, moderate level (on the biodegradation scale from 1 to 10). According to previous research, in the fourth, heavy level, when intensive changes of phenanthrene and its methyl isomers begin, n-alkanes have already been completely removed. In this paper, the ex situ natural bioremediation (non-stimulated bioremediation, without addition of biomass, nutrient substances and biosurfactant) of soil contaminated with heavy residual fuel oil (mazut) was conducted during a period of 6 months. Low abundance of n-alkanes in the fraction of total saturated hydrocarbons in the initial sample (identification was possible only after concentration by the urea adduction technique) showed that the investigated oil pollutant was at the boundary between the third and the fourth biodegradation level. During the experiment, an intense degradation of phenanthrene and its methyl-, dimethyl- and trimethyl-isomers was not accompanied by the removal of the remaining n-alkanes. The abundance of n-alkanes remained at the initial low level, even at end of the experiment when the pollutant reached one of the highest biodegradation levels. These results showed that the non-stimulated biodegradation of some hydrocarbons, despite their high biodegradability, had not proceeded completely to the end, even at final degradation stages. Under the condition of reduced availability of some hydrocarbons, microorganisms tend to opt for the less biodegradable but more accessible hydrocarbons.Dobro je poznato da se u toku biodegradacije nafte u prirodnim geološkim uslovima, ili naftnog zagađivača u životnoj sredini, degradacija ugljovodonika odigrava prema definisanom rasporedu. Na primer, glavne promene u procesu razgradnje normalnih alkana dešavaju se u toku drugog, "blagog", i trećeg, "umerenog", stupnja (na skali biodegradacije od 1 do 10). Prema dosadašnjim istraživanjima, u četvrtom stupnju, kada počinju intenzivne promene fenantrena i njegovih metil izomera, normalni alkani su već u potpunosti uklonjeni. U ovom radu u toku perioda od 6 meseci izvođena je ex situ prirodna bioremedijacija (nestimulisana bioremedijacija bez dodatka biomase, hranljivih sastojaka i biosurfaktanata) zemljišta zagađenog mazutom. Niska obilnost normalnih alkana u frakciji ukupnih zasićenih alkana u početnom uzorku (identifikacija je bila mogućna tek nakon koncentrovanja pomoću karbamida) pokazala je da je ispitivani naftni zagađivač na granici između trećeg i četvrtog stupnja biodegradacije. Tokom eksperimenta, intenzivnu razgradnju fenantrena i njegovih metil, dimetil i trimetil izomera nije pratilo uklanjanje ostatka normalnih alkana. Njihova obilnost je ostala na početnom, niskom nivou i na kraju eksperimenta kada je zagađivač dostigao jedan od najviših stepena biodegradacije. Dobijeni rezultati su pokazali da se razgradnja pojedinih ugljovodonika uprkos njihovoj visokoj biodegradabilnosti ne odigrava do potpunog kraja ni u završnim fazama degradacije. U uslovima njihove smanjene dostupnosti, mikroorganizmi se opredeljuju za teže degradabilne, ali dostupnije ugljovodonike