This paper has investigated experimentally the dynamic buckling behavior of AISI 303 stainless steel Aluminized and as received long columns. These columns, hot-dip aluminized and as received, are tested under dynamic buckling, 22 specimens, without aluminizing (type 1), and 50 specimens, with hot-dip aluminizing at different aluminizing conditions of dipping temperature and dipping time (type 2), are tested under dynamic compression loading and under dynamic combined loading (compression and bending) by using a rotating buckling test machine. The experimental results are compared with Perry Robertson interaction formula that used for long columns. Greenhill formula is used to get a mathematical model that descripts the buckling behavior of the specimens of type (1) under dynamic compression loading. The experimental results obtained show an advantageous influence of hot-dip aluminizing treatment on dynamic buckling behavior of AISI 303 stainless steel long columns. The improvement based on the average value of critical buckling stress, are as follow: (64.8 %) for long columns type (2), compared with columns type (1), under dynamic compression loading, and (56.6 %) for long columns type (2), compared with columns type (1), under dynamic combined loading, and (33.3 %) for long columns type (2) compared with Perry Robertson critical buckling stress.
Due to the specific characteristic of porcelain, the insertion of Beryllium oxide has been studied. The basic materials and quantities were selected carefully. In this work, porcelain containing 32 wt% feldspar, 24 wt% quartz and 44 wt% clay was synthesized and beryllium oxide (BeO) (1 wt.%, 3 wt.%, 5 wt% and 7wt%) were add. The basic and new composition porcelain powders were uniaxially compacted into standard samples dimensions and fired at various sintering temperatures, 1100°C, 1300°C, and 1450°C then held for 2 hour in a furnace.
The effects of sintering temperatures and beryllium oxide content on mechanical, electrical and structural properties were studied. The increasing of sintering temperature on the basi
... Show MoreObstacle avoidance is one of the major tasks needed to be carefully focused by the autonomous system designers. In this digital era, most industries are moving towards autonomous systems. Obstacle avoidance is considered as a primary concern for any autonomous system. In this paper, a prototype of an autonomous vehicle is presented, which is capable of obstacle avoidance using an ultrasonic sensor for its movement and avoidance. An Arduino microcontroller is used to achieve the desired operation. In order to achieve the desired task of the proposed system, a proper methodology is followed which combines appropriate selection of hardware components as well as logic design of actions for obstacle avoidance. The proposed system can
... Show MoreGround penetrating radar (GPR) technology is used to determine the extent to which this technique can detect with a high-frequency range from 10 MHz to 1000 MHz into the ground by a transmitting antenna and A graveyard was found beneath the depth of the three meters under Surface of the earth in the shrine of the Prophet Houd and Saleh in Al-Najaf Governorate surveyed by through 4 tracks. Ground Penetrating Radar (GPR) is a device that transmits short pulses of electromagnetic energy with pulse duration about 1 ns to 20 ns. applying the filter Time- Zero to the same profile at a depth (3m) , Two types of antennas were used in this study, with two different frequencies antennas (250, 500 )MHz Three tracks (23,25,2
... Show MoreThe plant Abrus precatorius, which belong to Leguminosae (Fabaceae) family and known as Crab’s eyes, Rosary pea with characteristic red and black seeds. It was used in folk medicine in India, China and East Asian countries for treatment of various diseases.
The plant was extracted by '' general method of extraction'' (Harborne, 1973) using 80% aqueous ethanol as a solvent of extraction by soxhlet apparatus. Preliminary qualitative phytochemical screening were performed on the crude ethanolic extract and revealed the presence of alkaloids, flavonoids ,terpenoids and phytosterols in Iraqi Abrus pr
... Show MoreThis research aims to reveal the quality standards available in press images published in the news sites, the Iraqi News Agency and Al-Mada Press for the period from: 1/9/2019, to: 30/9/2019. The research is a descriptive research, in which the researcher relied on the survey methodology to achieve its objectives. The research reached a number of results, most notably the weak role of photojournalists in the websites and the adoption of those the Internet as a source for obtaining press images published with news and reports through its pages, as well as the neglect of the standard Description/Comment below the press images, which plays an important function in explaining and interpreting them for users.
In this work, a step-index fiber with core index and cladding index has been designed. Single-mode operation can be obtained by using a fiber with core diameters 4–13 µm operating at a wavelength of 1.31 µm and by 4–15 µm at 1.55 µm. The fundamental fiber mode properties such as phase constant, effective refractive index, mode radius, effective mode area and the power in the core were calculated. Distributions of the intensity and the amplitude were shown.
In this paper, the author established some new integral conditions for the oscillation of all solutions of nonlinear first order neutral delay differential equations. Examples are inserted to illustrate the results.
This paper is concerned with the oscillation of all solutions of the n-th order delay differential equation . The necessary and sufficient conditions for oscillatory solutions are obtained and other conditions for nonoscillatory solution to converge to zero are established.
One hundred thirty - five clinical specimens of urine, blood, teeth root canal and burns were obtained from patients in hospitals of Baghdad. The specimens were cultured on Pfizer Selective Enterococcus agar to purify Enterococci isolates. 20 E. faecalis isolates were identified biochemically by growing in 10Cº, 45Cº, 6.5% NaCl, at pH 9.6 and confirmed by VITEK. Determination of Vancomycin-Resistant E. faecalis isolates were done by the minimum inhibitory concentrations [MICs] using agar dilution method. Seventeen E. faecalis isolates were determined as Vancomycin-Resistant and Intermediate Resistant.
This study aims to investigate the behavior and strength of self-compacted ferrocement slabs under punching shear load. Experimental results of thirteen square ferrocement slabs of 500×500 mm simply supported on all edges are presented. The main parameters investigated include the volume fraction of reinforcement, slab thickness and size of load-bearing plate. The load deflection and cracking characteristics of the tested slabs are studied and compared. The test results showed that the volume fraction of wire mesh has significant effect on both ultimate load and displacement. The increase of slab thickness leads to decrease in deflection values and increase in stiffness of slabs. Both ductility and stiffness increase as the
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