Experimental and Finite Element Analysis of Lateral Torsional Buckling of Concrete Filled Tubular Flange Steel Girders

The structural behavior of concrete filled Tubular Flange Girders (CFTFGs) has been studied in this research. This study aims to investigate the ability of tubular flange to increase resistance of steel girders against Lateral- Torsional Buckling (LTB). For this purpose, experimental, and numerical analysis were carried out.The experimental work consisted of fabricating and testing of five specimens. The first specimen with flat plate flange considered as a control specimen and the other specimens with tubular flanges. In tubular flanges specimens the effect of filled and non-filled tubular flanges with concrete also, the geometry effect of tubular flange sections, i.e. depth (40 and 20 mm) were studied. These specimens have the same length (1920 mm) and the same overall depth (170 mm). The specimens were tested under two point loads applied at the third-span points. The second part was a numerical one using the finite element method by software package (ANSYS 14), then employed to investigate the nonlinear behavior of tubular flanges girders and a similar numerical study of conventional I-girders was conducted, then the results compared with those of tubular flange girders.The measured experimental results were; the ultimate load capacity, load- vertical deflection, load- lateral deflection and load- twisting angle. Finally, the tubular flange specimens increased the lateral torsional buckling capacity comparing with the standard I-shaped steel members by about (66-97%), while bending strength increased by about (33-55%) for tubular flange section filled with concrete of 42.5 MPa. The concrete filled tubular flange increased the LTB capacity by about (14- 22 %) comparing with the unfilled specimens, also increased the flexural strength by about (13-22%). Thus, tubular flanges girders allowed using for large unbraced girders due to increasing the torsional stiffness of the girder. The numerical models were carried out by software package (ANSYS 14). The results were found to be in a convergent state with those obtained from the experimental tests. Keywords: Lateral–torsional buckling, finite element analysis, and tubular flange girder.

Finite Element Analysis of Concrete Beam under Flexural Stresses Using Meso-Scale Model

Two dimensional meso-scale concrete modeling was used in finite element analysis of plain concrete beam subjected to bending. The plane stress 4-noded quadrilateral elements were utilized to model coarse aggregate, cement mortar. The effect of aggregate fraction distribution, and pores percent of the total area – resulting from air voids entrapped in concrete during placement on the behavior of plain concrete beam in flexural was detected. Aggregate size fractions were randomly distributed across the profile area of the beam. Extended Finite Element Method (XFEM) was employed to treat the discontinuities problems result from double phases of concrete and cracking that faced during the finite element analysis of concrete beam. Cracking was initiated at a small notch located at the middle of the bottom face of the concrete beam. The response of plain concrete beam subjected to pure bending via two point load application was detected using (XFEM) analysis of meso-scale concrete model. Assuming full bond between aggregate particles, and mortar at interfacial zone, the flexural strength of plain concrete beam is increased when aggregate particles size is increased, so that bending and shear stress were affected by void percentage and aggregate particles distribution. The maximum deflection at midspan was increased when the aggregate particles size decreases

The physics and kinematics of the evolved, interacting planetary nebula PN G342.0-01.7

Here we aim to study the physical and kinematical characteristics of the unstudied old planetary nebula (PN) PN G342.0-01.7, which shows evidence of interaction with its surrounding interstellar medium. We used Integral Field Spectra from the Wide Field Spectrograph on the ANU 2.3 m telescope to provide spectroscopy across the whole object covering the spectral range 3400-7000 {\AA}. We formed narrow-band images to investigate the excitation structure. The spectral analysis shows that the object is a distant Peimbert Type I PN of low excitation, formally of excitation class of 0.5. The low electron density, high dynamical age, and low surface brightness of the object confirm that it is observed fairly late in its evolution. It shows clear evidence for dredge-up of CN-processed material characteristic of its class. In addition, the low peculiar velocity of 7 km s$^{-1}$ shows it to be a member of the young disk component of our Galaxy. We built a self-consistent photoionisation model for the PNe matching the observed spectrum, the H$\beta$ luminosity, and the diameter. On the basis of this we derive an effective temperature $\log T_{\rm eff} \sim 5.05$ and luminosity $1.85 < \log L < 2.25$. The temperature is much higher than might have been expected using the excitation class, proving that this can be misleading in classifying evolved PNe. PN G342.0-01.7 is in interaction with its surrounding interstellar medium through which the object is moving in the south-west direction. This interaction drives a slow shock into the outer PN ejecta. A shock model suggests that it only accounts for about 10\% of the total luminosity, but has an important effect on the global spectrum of the PN.Comment: 15 pages, 6 figures, A&A accepted 201

Optimize of LIBS Setup to the Determination of Laser Breakdown Power of Writing Inks

Laser-induced breakdown spectroscopy system (LIBS) had been designed to the determinate of the best ionization laser power for analysis of the writing inks via analysis induced plasma emission. Passively Q-Switched Nd:YAG laser at the fundamental wavelength 1064 nm  with different  energies (60 mJ,80mJ, 100 mJ, 200 mJ, 300mJ, 400mJ and 500 mJ) with (10 ns) pulse duration, the laser beam was focused via converging lens with focal length (100 mm) that generates different power intensity, optical spectrum analysis system used was within (Si-CCD)  array detector, within spectrum range of (200 - 900 nm) with (0.8 nm) optical resolution. Use A4 sheets of commercially available standard white office paper with 2 Ballpoint pens and 1 Gel pen as samples. Show the results that the laser energy (80 mJ) with (  power density, was the best power to generate plasma homogeneous for all component writing inks and ionize it without effect on the paper material. Keywords: LIBS, Laser intensity, Writing inks, White paper, plasma emissions lines, emission line analyses DOI: 10.7176/CPER/61-05 Publication date: July 31st 201

Electrodeposition of NiCr Nanowires Using Anodic Aluminum Oxide

&nbsp;يشير هذا البحث الى تصنيع اسلاك نانوية لسبيكة نيكل-كروم بواسطة الترسيب الكهروكيميائي. انجز الترسيب الكهروكيميائي على اساس من اوكسيد الالمنيوم المؤنود ( AAO ) ذات ثقوب نانوية قطرها ( 70 nm ). تمت عملية الانودة للالمنيوم بأستعمال حامض الاوكزالك وذلك بخطوتين من الانودة للحصول على الاساس AAO ثم تلاها ترسيب سبيكة نيكل-كروم من املاح كبريتات النيكل وكبريتات الكروم وكانت نسب العناصر الناتجة للسبيكة هي 72.3Ni27.7Cr . الاسلاك النانوية الناتجة تم تشخيصها بأستعمال المجهر الالكتروني SEM والمجهر الالكتروني TEM.ان الاسلاك النانوية الناتجة تمتلك قطر بمقدار( 70 nm ) وطول ( 420-500 nm ).This research highlights fabrication of NiCr nanowires by electrochemical deposition. The deposition was achieved using anodic aluminum oxide AAO template with 70 nm diameter of pores. The anodization was performed using oxalic acid with two steps to obtain AAO template. 72.3Ni27.7Cr nanowires were obtained using nickel and chromium sulfate. The nanowires were characterized by SEM and TEM. The obtained nanowires with 70 nm diameter and 420-500 nm length

Cusp deflection and fracture strength of root canal filled premolars with two access cavities designs (Conservative vs Traditional)

This study evaluated two endodontic access designs (Conservative (Cons) vs Traditional (Trad)) of class I and class II cavities on cusp deflection (CD) and fracture strength (FS) of root canal filled maxillary premolars. Seventy-two sound maxillary firs

Influence of Cold Plasma on Sesame Paste and the Nano Sesame Paste Based on Co-occurrence Matrix

يهدف البحث الى معرفة تأثير البلازما الباردة على البكتيريا المزروعة على راشي السمسم في جسيماته الطبيعية وحجم جسيمات النانو. بدءًا من استخدام عملية تجزئة الصور اعتمادًا على طريقة العتبة، يتم استخدامها للتخلص من انعكاس الشرائح الزجاجية التي توضع عليها عينات السمسم. تم تنفيذ عملية التصنيف لفصل راشي السمسم الطبيعي عن غير الطبيعي. الراشي غير الطبيعي يظهرعندما نمت البكتيريا على راشي السمسم بعد تركه  لمدة يومين في الهواء، ان عملية التصنيف الموجه  معدل k-  استخدمت  لتصنيف المنطقة المصابة والمنطقة الطبيعية والمنطقة المعالجة. والبكتريا المعالجة بالبلازما الباردة، مدة التعرض دقيقتان. تم حساب الميزات التركيبية المتعلقة بمصفوفة التدرج اللوني ذات المستوى الرمادي للنسيج الطبيعي وغير الطبيعي والمعالج، ومن الواضح أن مجموعة  النسيج المعالج لها أفضل الميزات مقارنة باالمجاميع  الأخرى. أظهرت النتيجة أن راشي السمسم المعالج بالبلازما له نتائج جيدة مقارنة مع راشي السمسم النانوي  المعالج بالبلازما. وذلك لأن البلازما تزود راشي السمسم بالحرارة وتجعل جزيئات السمسم النانوية تتجمع معًا.The aim of the research is to investigate the effect of cold plasma on the bacteria grown on texture of sesame paste in its normal particle and nano particle size. Starting by using the image segmentation process depending on the threshold method, it is used to get rid of the reflection of the glass slides on which the sesame samples are placed.  The classification process implemented to separate the sesame paste texture from normal and abnormal texture. The abnormal texture appears when the bacteria has been grown on the sesame paste after being left for two days in the air, unsupervised k-mean classification process used to classify the infected region, the normal region and the treated region. The bacteria treated with cold plasma, the time exposure is two minutes. The textural features related to gray level co-occurrence matrix are calculated for the normal, abnormal and the treated texture, it is obvious that the treated texture class has the best features compared with the other classes. The result shows the sesame paste treated with plasma has good result compared with nano sesame paste treated with plasma.  This is because the plasma provides the sesame paste with heat and makes the sesame nano particle congregate together

Synthesis and Thermal Characterization of Copolymers Containing Amino Acids

Thee copolymers of amino acid were synthesized in two steps. First, the amino acids react with resorcinol to formation of azo monomers step. They led in a second condensation polymerization step to copolymeric materials. The structures of the copolymers were characterized by means of FT-IR and 1H-NMR spectroscopy. The thermal properties were investigated by TGA and DTG. Keywords: copolymers, amino acid, thermal properties, azo compoun