Abstract

This paper represents a study of the effect of the soil type, the drilling parameters and the drilling tool properties on the dynamic vibrational behavior of the drilling rig and its assessment in the drilling system. So first, an experimental drilling rig was designed and constructed to embrace the numerical work.

The experimental work included implementation of the drill-string in different types of soil with different properties according to the difference in the grains size, at different rotational speeds (RPM), and different weights on bit (WOB) (Thrust force), in a way that allows establishing the charts that correlate the vibration acceleration, the rate of penetration (ROP), and the power

Cyanobacteria are prokaryotic photosynthetic communities which are used in biofertilization of many plants especially rice plant. Cyanobacteria play a vital role to increase the plant's ability for salinity tolerance. Salinity is a worldwide problem which affects the growth and productivity of crops. In this work three cyanobacteria strains (Nostoc calcicola, Anabaena variabilis, and Nostoc linkia) were isolated from saline soil at Kafr El-Sheikh Governorate; North Egypt. The propagated cyanobacteria strains were used to withstand salinity of the soil and increase rice plant growth (Giza 178). The length of roots and shoot seedlings was measured for seven and forty days of cultivation, respectively. The results of this investigation showed

This paper presents the syntactic dimension of ditransitive verbs in terms of the universal theory of Role and Reference Grammar (RRG). This theory is syntactic in nature, but it also covers the semantic as well as the pragmatic aspects of any linguistic phenomenon. It assumes a universal framework through which syntactic constructions can be analyzed. However, the morphological structure that each language enjoys renders the universal treatment more complicated and can question the universal nature of such a theory. In this paper, an attempt is made to check if the universal tenet of the theory is maintained over two typologically different languages: English and Arabic in respect of the way that double-object constructions (DOCs)

the shear strength parameters of the treated and untreated gypsum soil under the effect of four soaking and drying cycles has studied in this paper, moreover examined the effect of wetting and drying cycles on the collapse potential of the soil and comparing between the behavior of the treated and untreated gypsum soil under the effect of the two conditions. Gypsum soil sample brought from Sawa lake in Al Muthana governorate with the content of gypsum 65.5%, the polyurethane polymer (PP) was used with different percentages 3, 6, and 10% to enhance the mechanical properties of gypsum soil, model was prepared to achieve four soaking and drying cycle to the samples before testing, this model consists of an Aluminum plate base with dimensions 7

For a nonempty subset X of a group G and a positive integer m , the product of X , denoted by Xm ,is the set Xm = That is , Xm is the subset of G formed by considering all possible ordered products of m elements form X. In the symmetric group Sn, the class Cn (n odd positive integer) split into two conjugacy classes in An denoted Cn+ and Cn- . C+ and C- were used for these two parts of Cn. This work we prove that for some odd n ,the class C of 5- cycle in Sn has the property that = An n 7 and C+ has the property that each element of C+ is conjugate to its inverse, the square of each element of it is the element of C-, these results were used to prove that C+ C- = An exceptio

Partial shading is one of the problems that affects the power production and the efficiency of photovoltaic module. A series of experimental work have been done of partial shading of   monocrystalline PV module; 50W, I_sc: 3.1A, V_oc: 22V with 36 cells in series is achieved. Non-linear power output responses of the module are observed by applying various cases of partial shading (vertical and horizontal shading of solar cells in the module). Shading a single cell (corner cell) has the greatest impact on output energy. Horizontal shading or vertical shading reduced the power from 41W to 18W at constant solar radiation 1000W/m² and steady state condition. Vertical blocking a column

Organic soil is problematic soils in geotechnical engineering due to its properties, as it is characterized by high compressibility and low bearing capacity. Therefore, several geotechnical techniques tried to stabilize and improve this soil type. In this study, sodium silicate was used to stabilize sand dune columns. The best sodium silicate concentration (9%) was used, and the stabilized sand dune columns were cured for seven days. The results for this soil were extracted using a numerical analysis program (Plaxis 3D, 2020).In the case of studying the effect of (L/D) (where ‘’L” and ‘’D’’ length and diameter of sand dune columns) of a single column of sand dunes stabilized with sodium silicate with a diff

In the present research, the chemical washing method has been selected using three chelating agents: citric acid, acetic acid and Ethylene Diamine Tetraacetic Acid (EDTA) to remove 137Cs from two different contaminated soil samples were classified as fine and coarse grained. The factors that affecting removal efficiency such as type of soil, mixing ratio and molarity have been investigated. The results revealed that no correlation relation was found between removal efficiency and the studied factors. The results also showed that conventional chemical washing method was not effective in removing 137Cs and that there are further studies still need to achieve this objective.

The materials of soil were affected by multi reasons; such as human activities, floods, tidal waves, ... etc. The change of the soil contents could be measured through different indexes; such as electric conductivities, salinity, concentration of the heavy elements, and concentration of essential elements ... etc. The land cover is affected by natural influences, like tidal energy, which plays a negative role in the salinization of land adjacent to the coasts, causing a problem for soils in all its details represented in changing of the dissolved elements in soil. One of the most important natural factors that cause soil salinity is human activity in all its forms, and one of the most important causes of salinity is the phenomenon o