Algerian Journal of Engineering and Technology (AJET)
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Vulnerability of potential soil erosion and risk assessment at hilly farms using InSAR technology
No full textSoil erosion is a serious environmental challenge which is persistently diminishing the available land resource in many places around the world, particularly the highlands areas. The traditional approach of estimating the magnitude of erosion is tedious, costly and considerably time consuming. This study is aimed at assessing the risk level associated with soil erosion at hilly areas of Cameron Highlands through Interferometric Synthetic Aperture Radar (InSAR). The digital elevation model with 5 m resolution was utilized to generate the slope map for the highlands. Soil erosion rates was estimated using universal soil loss equation, while information about land use and cover were sourced from relevant government agencies. The analysis shows that, there was about 217.5 km2 (30.5%) of highlands fall under severely steep zone with slope ≥ 45o. Moreover, erosion risk assessment indicated that; 66.3%, 11.4%, 11.7% and 10.8% of the severe sloppy lands are classified as very low to high susceptible to soil erosion respectively. In general, the risk of soil erosion is relatively low and could be attributed to large vegetation coverage despite steep slopes. However, there is need to deploy a control measures to reduce soil disturbance activities on highlands with extremely steep slope as a proactive measures to minimize the effect of potential soil erosion
 
Influence of a different fault scenarios on the properties of multi-phase induction machine
Get PDFThis paper deals with the influence of a stator fault, power switch faults and open phase fault conditions on the properties of a five-phase induction machine under open-end stator winding (OeW-FPIM). This paper will develop an accurate mathematical model to simulate the faulty OeW-FPIM drives. The proposed model is based on the theory of electromagnetic coupling of electrical circuits coupled to the differential equation system governing the machine behavior in presence of the stator winding faults. In fact, when a short circuits between coils occurs, the stator winding function of the injured phase changes. As a consequence, the stator resistance, the stator inductance of this phase and its mutual inductance with all the other circuits change also. Consequently, the inductances and resistance matrices will be changed by taking into account the introduced coefficients of short-circuited turns. The performance of the OeW-FPIM drives have been tested via simulation under different fault scenarios conditions.
 
Corrosion inhibition potentials of Strichnos spinosa L. on Aluminium in 0.9M HCl medium: experimental and theoretical investigations
Get PDFAluminium is known as one of the most useful metals on earth which is also subject to corrosion under certain environments. Many methods have been used to minimize its corrosion, but the use of inhibitors is widely accepted. The use of green inhibitors has gained wide usage because of its environmental friendliness. The experimental studies of the corrosion inhibition potentials of Strichnos spinosa L was carried out using weight-loss and Fourier transform infrared spectroscopy (FTIR), whereas theoretically, quantum chemical parameters and molecular dynamic stimulations of some compounds isolated from the plant in literature were studied. The analyses of the experimental results showed that the extract of Strichnos spinosa L. extract decreased the corrosion rate of Aluminium in 0.9M HCl in the order: 0.2g/l < 0.4g/l < 0.6g/l respectively from 303-323K. The inhibition efficiency decreased with increase in temperature and was found to be 84.7%. FTIR results showed that the inhibition mechanism is physical through the functional groups present in the extract. The data obtained were fitted into various adsorption isotherms and relatively the Freundlich isotherm was found to be the best fit. Relying on quantum chemical parameters and molecular dynamic stimulations results, the adsorption/binding strength of the concerned inhibitor molecules on Aluminium surface follows the order Ursolic acid>Betulinic acid>Erythrodiol. The computed adsorption/binding energy values (Eads) for the various isolated compounds from the plant indicate the adsorption process to be non-covalent (physiosorption) which is in good agreement with the experimentally determined adsorption mechanism.
 
Global nucleophilicity as electronic property for the study of Hydrogen storage materials capacities
No full textOur aim in the present work is to perform a theoretical study of the efficiency on hydrogen storage of a series of metal functionalized systems by means of global reactivity indices derived from density functional theory, and put in evidence the ability of the nucleophilicity whitch is a simple global index to explain material hydrogen storage. In the present paper theoretical calculations were carried out at the M05-6/6-311+G(d) level of the theory by means of Gaussian 09 software. All systems geometries were optimised at the same level and the global indices were then evaluated using the optimised structures. The studied systems were divided into two series where the first series contained 12 systems MX each (M=Li, Na, K; X=H, AlH4, BH4, NH2) and the second one contained 8 systems MX2each (M=Mg, Ca). The obtained results and after comparison with experimental data, showed that nucleophilicity index is directly related to the predicted storage capacities by inversed trends. Considering the obtained results, it can concluded that Density Functional Theory (DFT) derived indices namely nucleophilicity is an important parameter which can be used for modelling and designing a potential new hydrogen storage material
Study of corrosion inhibition performance of Glutaraldehyde on Aluminium in nitric acid solution
No full textThe inhibition effect of glutaraldehyde on the corrosion behavior of aluminium in 1.4 M nitric acid solution was studied using weight loss method, adsorption studies and characterized instrumentally by Fourier Transform Infrared Spectroscopic (FT-IR) analysis. The effects of inhibitor concentration, temperature and surface coverage were all investigated. The effect of inhibitor concentration and other parameters were evaluated for different inhibitor concentrations and the probable mechanism for the studied inhibitor was also proposed. The results showed that glutaraldehyde possess an excellent inhibiting effect toward the corrosion of aluminium in nitric acid solution with highest inhibition efficiency of 84.68, 81.34 and 76.87 % at 308, 313 and 318 K in the presence of 0.1 M inhibitor concentration. The values of the activation energy, rate constant, half-life and rate constant in uninhibited acid solution were 31.84 kj mol-1, 3.9 k ×10-3 hr-1 and 1.76 × 102 hr which changed to 57.64 kj mol-1, 0.60 k ×10-3 hr-1 and 11.55 hr in the presence of 0.1 M inhibitor concentration. The positive values of enthalpy reflect the endothermic nature of the reaction. The negative values of entropy (ΔS) signified that the activated complex in the rate determining step represented an association, rather than dissociation. The adsorption of the inhibitor on the metal surface followed Langmuir adsorption isotherm
Strength analysis of concrete pavement deformation due to Alkali Silica Reaction (ASR)
No full textAlkali Silica Reaction (ASR) is a chemical reaction that negatively affects concrete pavements strengths and integrity. ASR impedes concrete pavements' performance due to the formation of cracks and ultimate deformation if not properly controlled. Concrete pavements are gaining more relevance due to their ability to be constructed on soils with low bearing capacity and support high traffic loadings, thus increasing the need for studies on how ASR in the concrete pavements can be mitigated. This study employed compressive and flexural strength tests to determine the strength properties and deformation of concrete pavements due to ASR when partially replaced with CBA at varying percentages. Static structural modelling of the concrete as a multiphase material in which aggregates, cracks and gel formations are considered as embedded inclusions in the cement paste is then carried out. The results are then compared with relevant standards and findings of other researchers. The study's findings reveal that all the concrete cube samples passed the recommended compressive strength for rigid pavement, which range from 35 - 40 N/mm2 at 28th day. The concrete cube samples also passed the target strength of 48.25 N/mm2 obtained from the mix design. The effect of ASR resulted in lower compressive and flexural strengths observed at 180th and 240th days with lower CBA addition, while samples containing higher CBA contents had increasing compressive strength. The static structural modelling results reveal that the maximum deformation was obtained for the concrete cubes admixed with 0% CBA with 47.045 mm while the least deformation was obtained at 30% CBA replacement with deformation value of 5.542 mm on application of a 900 KN force. Therefore, the study posits that CBA addition will help reduce Portland Cement Concrete Pavement deformation due to ASR in relation to traffic loadings.
 
Broken rotor bars fault detection in induction motors using FFT: simulation and experimentally study
Get PDFThis paper presents the fault detection of broken rotor bars based on the analysis technique, such as the fast Fourier transform (FFT), which utilize the steady-state spectral components of the stator quantities is considered. This technique has been given expected results, the accuracy of this technique depends on the loading conditions and constant speed of the motor. This method shows good theoretical and experimental results
An overview on desiccant assisted evaporative cooling in hot and humid climates
No full textIn last few decades due to global warming the temperature of the earth increases continuously day by day responsible for the increased energy demand for cooling the building space. Vapor compression based conventionally used traditional air conditioners consume tremendous energy for cooling the building. So, it is time to search for cooling system which maintains necessary thermal comfort at optimum energy use. Desiccant assisted evaporative cooling system having greater potential for use of renewable solar energy as well as effectiveness in terms of maintaining comfort in hot and humid climate. In the present paper, solid desiccant based evaporative cooling systems are reviewed and it is shown that desiccant assisted evaporative cooling perform better and displayed comparatively lower energy consumption as compared to the traditional air conditioning systems
Editorial Introduction to the First Issue of Algerian Journal of Engineering and Technology
No full textOn behalf of the editorial team and reviewers, the editor in chief, has great pleasure to present this first issue of the Algerian Journal of Engineering and Technology (AJET), for the worldwide research community, especially those who looking to publish their works and those want to keep up with the latest research. In our journal, we provide opportunities for all the scholars around the world to publish their scientific work without any publication fee
AJET journal was created in order to cover the remarkable shortage of the Algerian journals, and so, provide a chance to the Algerian and worldwide researchers to publish their scientific works, after reviewing them through a carefully selected researches from decent university and institution over the world; we promise that our peer review process for every paper submitted to AJET journal will be fast, reliable and looking forward the high quality of the succeed international worldwide journals. Moreover, we are committed to reply to all papers submitted in AJET journal by six weeks with an acceptance or rejection answers.
In addition, the journal provides an experienced and knowledgeable editorial board and reviewers in different fields of engineering, science and technology, who give valuable constructive comments and remarks to authors for improving their papers and possible publications in AJET.
The journal will achieve success through the commitment of its editorial board members, reviewers and the authors. Also, I hope through the high quality manuscripts published on the first issue of AJET journal, that we will provide the appropriate space for authors and motivate them to submit their work in AJET journal.
Finally, I am grateful to all the editorial board members and reviewers who they invested great team efforts in order to improve the quality of our journal
Identification, purification and quantification of Toxins “Ochratoxin A” in Algerian grape juice
No full textoai:jet.jetjournal.org:article/4This study aimed to investigate the mycotoxin of Ochratoxin A (OTA) which can contaminate grape in the Mediterranean basin. Its toxicity was the subject of many animal studies and carcinogenic characters are well established today. So the European Committee has fixed the maximum in grape 2µg/L. Most methods used for mycologic identification is based mainly on the morphological characters. It was identified after its purification by the technique of culture monospore on the culture medias Potatoes Agar and Czapek Yeast extract Agar. The detection and quantification of this mycotoxin by uses combined techniques: immunoaffinity for the purification and the HPLC coupled with the fluorometric detector. This chromatographic system allowed us to estimate the contamination of Ochratoxin in the grape which is lower than 30 ng/L. The concentration of conidia at Aspergillus section Nigri was estimated at 3×106conidia/mL. the value obtained is less than 30 ng / L and is lower than that fixed by the EC. So, we confirm that our sample does not present serious risks to human health. We have also confirmed fungus belonging to A. Niger specie, which normally does not produce OTA.