Effect of Microalloying Elements on the Heat Treatment Response and Tensile Properties of Al-Si-Mg Alloys

This study was carried out on a series of heat-treatable Al-Si-Mg alloys to determine the effects of Fe, Mg, Sr and Be addition on their microstructural characteristics and tensile properties. The results showed that the eutectic temperature was reduced by 10°C with 0.8 wt% Mg addition. The solidification curves and first derivatives of Sr-free alloys with high Fe and Mg contents revealed a peak at 611°C consequent to the formation of a script-like Be-Fe (Al8Fe2BeSi) phase, which was very close to the peak for α-Al. The morphology of the β-iron platelets underwent changes due to their dissolution, thinning, necking, and fragmentation with increase in solutionizing time. Increased Mg contents are beneficial to the tensile properties unlike the detrimental effect of increasing Fe contents. Additions of Be and Sr noticeably improved the properties at the same Fe and/or Mg contents, the enhancements being markedly observed at higher Mg contents and reduced Fe levels. At high Fe levels, addition of Be is preferable as it neutralizes the deleterious effects of Fe in these alloys; however, addition of 500 ppm Be is inadequate for interacting with other alloying elements

Evaluating the In vivo Efficacy of Copper-Chitosan Nanocomposition for Treating Vascular Wilt Disease in Date Palm

Date palm, Phoenix dactylifera, as one of the most important fruit crops in Egypt and many other countries, can be affected by many fungal diseases, among which the vascular wilt disease, caused by the fungal pathogen Fusarium oxysporum, is considered the most deteriorating one. This study aims at evaluating the efficiency of Copper-Chitosan Nanopcomposition for treating the vascular wilt disease in date palm. The study relies mainly on beleaguering the disease via the double-role functionality of copper-chitosan nanocomposition, i.e. its potential antifungal effect on the fungal pathogen, besides its capability to enhance the immune responses of the infected plant. In this regard, chitosan nanoparticles were prepared according to the ionic gelation method, whereas copper nanoparticles were prepared according to the chemical reduction method. Physicochemical characterization of both chitosan and copper nanoparticles was performed using dynamic light scattering (DLS), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR) and x-ray diffraction (XRD). Copper-chitosan nanocomposition could significantly reduce the vascular wilt disease severity; this means that the nanocomposition can be used in the future for developing new nano-fungicides to control such pathogens

Comparative study between fisher anatomical subunit approximation technique and millard rotation- advancement technique in unilateral cleft lip repair

Introduction: The ideal lip repair is characterized by; the symmetrical shape of nasolabial folds and both alae of the nose with a natural-looking philtrum and Cupid’s bow in both static and dynamic states, in addition to a hidden scar.Objective: to compare between Fisher anatomical subunit approximation technique and Millard rotational advancement technique in unilateral cleft lip repair.Methods: Prospective study for 40 patients presented to Alexandria Main University hospital with unilateral cleft lip deformity between March 2019 and October 2020. Twenty patients with unilateral cleft lip deformity were repaired by Fisher anatomical subunit approximation technique, while the other twenty were repaired by Millard rotational-advancement technique. The postoperative photographs of the patients were captured and processed in computer photogrammetry software through which anthropometric parameters including (lip height, lip width, vermilion height, and alar base width) were compared between the normal side and the repaired side. In this software, each anthropometric parameter length on the normal side is taken as a control with a fixed value of (1) then the same parameter on the repaired side was measured as a ratio of this value to avoid bias. Comparison between both groups for assessment of the quality of cleft lip repair was also done based on Steffensen grading criteria.Results: Comparison between both techniques in unilateral cleft lip repair showed that there was no significant difference between them in the anthropometric measurements. While the comparison between the two groups using Steffensen grading criteria showed that Fisher’s technique surpassed Millard’s technique.Conclusion: We recommend the use of the Fisher anatomical subunit approximation technique in unilateral cleft lip repair for its superior results over the Millard rotational advancement technique

Vibration Signature of Normal and Notched Tooth Gear Pump

Gear pumps are critical devices in many industrial applications. An unexpected failure of the gear pump may cause significant effect on its performance. Consequently, there will be economic losses. As a result of that, fault diagnosis in gears has been the subject of intensive research. Vibration analysis has been used as an effective tool in machines diagnosis and in machinery maintenance decisions. As a rule, an increased vibration level is a warning form before failure or breakdown. By measuring and analyzing the gear pump vibration, it is possible to determine both the nature and severity of the defect, and hence predict the machine’s failure. The vibration signal of a gear pump carries the signature of the fault in the gears, and early fault detection of the gear pump is possible by analyzing the vibration signal using different signal processing techniques. This paper presents, experimentally, the external gear pump signature for normal and faulty gear pumps at different rotational speeds (1080, 1200, and 1439rpm). The considered faults herein are two different notches on one of the pump teeth— small notch and large notch. The paper concludes that features of the vibration are different with the notch shape and the rotational speed. The amplitude of vibration increases by increasing both rotational speed and notch size

Preparation of Some Eco-friendly Corrosion Inhibitors Having Antibacterial Activity from Sea Food Waste

Chitosan is one of the important biopolymers and it is extracted from exoskeletons of crustaceans in sea food waste. It is a suitable eco-friendly carbon steel corrosion inhibitor in acid media; the deacetylation degree of prepared chitosan is more than 85.16 %, and the molecular weight average is 109 kDa. Chitosan was modified to 2-N,N-diethylbenzene ammonium chloride N-oxoethyl chitosan (compound I), and 12-ammonium chloride N-oxododecan chitosan (compound II) as soluble water derivatives. The corrosion inhibition efficiency for carbon steel of compound (I) in 1 M HCl at varying temperature is higher than for chitosan and compound (II). However, the antibacterial activity of chitosan for Enterococcus faecalis, Escherichia coli, Staphylococcus aureus, and Candida albicans is higher than for its derivatives, and the minimum inhibition concentration and minimum bacterial concentration of chitosan and its derivatives were carried out with the same strain

Invasive fungal infections and patients with malignancies in upper Egypt

The incidence of invasive fungal infections has increased considerably in recent years. The aim of this study was to present a suitable early diagnostic procedure in immune compromised patients, using detection of fungal infection of urine samples collected from 33 patients with malignancies (from 2-89 years old), during the period from December 2012 to February 2014, from South Egypt. Fifty-three fungal species representing 14 genera were collected during this investigation from urine samples on Sabouraoud’s Dextrose Chloramphenicol Agar (46 species and 12 genera) and Rose Bengal Chloramphenicol Agar media (41 species and 11 genera). Aspergillus (16 species), Penicillium (14 species), Yeasts (5 species) and Cladosporium (5 species) contributed the broadest spectra of species in all samples tested on two types of media used. Other species were represented by 13 species belonging to 10 genera. The results indicate that immune compromised patient is a suitable habitat for the growth and sporulation of different groups of fungi, both saprophytic and pathogenic. A variety of types of filamentous fungi were obtained from malignancies patients. Immunosuppressant patient’s exposure for fungal infection so should be in especial care from food, drinking and air. Published by the International journal of Microbiology and Mycology (IJMM

Adaptive Neuro Fuzzy Technique for Speed Control of Six-Step Brushless DC Motor

The brushless DC motors with permanent magnets (PM-BLDC) are widely used in a miscellaneous of industrial applications. In this paper, The adaptive neuro fuzzy inference system (ANFIS) controller for Six-Step Brushless DC Motor Drive is introduced. The brushless DC motor’s dynamic characteristics such as torque , current , speed, , and inverter component voltages are showed and analysed using MATLAB simulation. The  propotional-integral (PI) and fuzzy system controllers  are developed., based on designer’s test and error process and experts. The  experimential and hardware resuts for the inverter- driver circuits are presented. The simulation results using MATLAB simulink are conducted to validate the proposed (ANFIS) controller’s robustness and high performance relative to other controllers

The supply response of rainfed agricultural crops to price changes in South Darfur State, Sudan

The objective of this study is to examine the supply response of rainfed agricultural crops to price changes in South Darfur State. The study was based on data collected for the period 1987- 2004. The data included area, production, rainfall, and relative prices. The analysis of data was based on the Nerlovian partial adjustment model. The results revealed that the supply response of individual crops was positive but generally low in the short-run and fairly high in the long-run. These results could be a useful tool for policies intended to enhance the production efficiency of rainfed agriculture in the State. The study also demonstrated the importance of having adequate and timely adoption of agricultural technology to promote the low response of individual crops and to maintain a sustainable food security for the State

ALMA observations of the variable 12CO/13CO ratio around the asymptotic giant branch star R Sculptoris

[abridged] The 12CO/13CO ratio is often used as a measure of the 12C/13C ratio in the circumstellar environment, carrying important information about the stellar nucleosynthesis. External processes can change the 12CO and 13CO abundances, and spatially resolved studies of the 12CO/13CO ratio are needed to quantify the effect of these processes on the globally determined values. Additionally, such studies provide important information on the conditions in the circumstellar environment. The detached-shell source R Scl, displaying CO emission from recent mass loss, in a binary-induced spiral structure as well as in a clumpy shell produced during a thermal pulse, provides a unique laboratory for studying the differences in CO isotope abundances throughout its recent evolution. We observed both the 12CO(J=3-2) and the 13CO(J=3-2) line using ALMA. We find significant variations in the 12CO/13CO intensity ratios and consequently in the abundance ratios. The average CO isotope abundance ratio is at least a factor three lower in the shell (~19) than that in the present-day (60). Additionally, variations in the ratio of more than an order of magnitude are found in the shell itself. We attribute these variations to the competition between selective dissociation and isotope fractionation in the shell, of which large parts cannot be warmer than ~35 K. However, we also find that the 12CO/13CO ratio in the present-day mass loss is significantly higher than the 12C/13C ratio determined in the stellar photosphere from molecular tracers (~19). The origin of this discrepancy is still unclear, but we speculate that it is due to an embedded source of UV-radiation that is primarily photo-dissociating 13CO. This radiation source could be the hitherto hidden companion. Alternatively, the UV-radiation could originate from an active chromosphere of R Scl itself....Comment: 6 pages, 5 figures, online data available at http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=J/A+A/556/L