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Insecticidal and Histological Effects of Extracts from Leaves of Juglans regia L. Against Sitophilus oryzae (Coleoptera: Curculionidae) Isolated from Soft Wheat in Post-harvest
No full textIn Algeria, the cultivation of soft wheat (Triticum aestivum Linn.) plays a crucial role in the food chain. However, the crop faces a threat from Sitophilus oryzae (Coleoptera: Curculionidae), which causes substantial economic losses. This study aims to discover novel bioactive compounds derived from Juglans regia Linn., a walnut tree grown in Algeria, to combat S. oryzae. This study focuses on extraction, phytochemical characterization, insecticidal effect against S. oryzae adults, and histological impact. GCMS analysis of the petroleum ether (EPJ) and chloroform (CHJ) fractions indicated the presence of a diverse range of bioactive molecules, including myrtenal (1.17%), eugenol (46.17%), methyl ester (25.84%), lycophyll (5.16%), and hexadecane (1.22%), which are derived from terpenoids, phenols, and fatty acids. LCMS/MS analysis of the ethyl acetate (AEJ) and butanolic (BTJ) fractions identified compounds mainly associated with hydrocinnamic acids, flavonols, flavones, and naphtoquinones, such as 3-caffeoylquinic acid, epi-catechin isomer, kaempferol-3-glucoside, and hydro-juglone derivative. Furthermore, the efficacy of the five extracts (hydromethanolic extract and the four fractions) against S. oryzae adults was evaluated at 625, 315, and 75 µg/mL concentrations over 7 days. EPJ and BTJ demonstrated the highest effectiveness among these extracts, as indicated by their relatively low LC50, LC90, LT50, and LT90 values. These results highlight the potential of EPJ and BTJ, derived from walnut leaves, as biocontrol agents against S. oryzae. Histological analysis of the treated insects revealed significant alterations in various tissues compared to untreated adults. This research gives the first evidence that J. regia grown in Algeria is a promising biocontrol agent against pest beetles in stored soft wheat
Exceptional photocatalytic performance of hexagonal ZnO nanorods for anionic and cationic dyes degradation
No full textThis study presents an in-depth investigation of zinc oxide hexagonal nanorods (ZnO NRs) synthesized via a hydrothermal approach at three pH basic values conducted in high-pressure laboratory reactor provided by Parr Instrument Company. The research evaluates the catalytic properties of the ZnO NRs, highlighting their potential for environmental applications. The as-fabricated samples are characterized by various techniques including the X-ray diffraction (XRD), UV–visible spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) analysis, Field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray analysis (EDAX) and high-resolution transmission electron microscopy (HR-TEM). Rietveld refinement of X-ray diffraction data reveals the formation of high-purity hexagonal Wurtzite-type ZnO phase. Further, it is investigated that by decreasing the pH values, the grain size of ZnO NRs increases from 25.70 nm to 29.91 nm. SEM analyses further confirmed the hexagonal nanorod-shaped morphology of ZnO. The photocatalytic degradation performance of the as-fabricated ZnO NRs for Methylene Blue (MB) and Methyl Orange (MO) dyes increased with the increase in pH value, reaching almost 95 % and 64 %, respectively, after 30 min of UV irradiation. The optimum degradation is achieved at a pH value of 11
One-dimensional model of heat exchanging throughout a three-dimensional building room integrated by phase change material
No full textThis paper presents a numerical investigation aimed at analyzing heat exchange and thermal comfort conditions within a building room during the hot season. In this setup, one wall, the roof, and the floor are thermally insulated, while the remaining three walls are constructed with brick embedded with phase change material (PCM). These non-insulated walls are subjected to a constant external surface temperature. Additionally, a latent heat storage unit comprising a set of tubes is installed in the room's ceiling region.
The mathematical model employed in this study is based on pure conduction in the brick and in the walls containing PCM, as well as natural convection in the room air. Natural convection within the liquid phase of the PCM storage unit is accounted for by considering the effective thermal conductivity's dependence on the liquid fraction. The enthalpy method is utilized to solve energy equations in both the solid and liquid phases of the PCM, whether in walls or tubes. Heat transfer within the room is assumed to be unidirectional through the walls and tubes, with zero-dimensional considerations in the air region. The developed model is thoroughly analyzed and compared with existing literature, showing good agreement. Subsequently, a parametric study investigating various geometrical and thermo-physical parameters of the building room is conducted. The results indicate that the PCM within the walls contributes to maintaining indoor temperatures within the comfort range. Furthermore, the heat storage unit helps sustain indoor temperatures at the comfort level as long as the PCM within the tubes is undergoing melting processes
DFT-based, Monte Carlo and Grand Canonical Monte Carlo simulations of nitro-organic pollutants 4-nitrophenol, 2-nitrophenol, 9-nitroanthracene and nitrogen trifluoride interacting with water in zeolite imidazole framework (ZIF-8)
No full textWe report in this study the behaviour of adsorbed Nitrogen-volatile organic compounds (NVOCs) such as 2NP (2-Nitrophenol), 4NP (4-Nitrophenol), 9NAnt (9-Nitroanthracene), NF3 (Nitrogen trifluoride) with and without water in Zinc-Imidazolate Framework (ZIF-8) using the Density Functional Theory (DFT). The work considers both single and multiple molecular capture of different species of pollutants, along with theoretical research based on force fields to determine the maximum number of molecules that can be loaded inside the material. Negative adsorption energy is obtained when each pollutant is considered separately or in mixtures. The values range from −2.6 kJ/mol to −137.1 kJ/mol depending on the size of adsorbed species. Modelling of the adsorbed pollutants on ZIF-8 towards the use of the code CASTEP show the possible interaction with the imidazole rings of the bulk crystal. The interaction energy (Eint) indicates that the capture of 2NP and 4NP is more favourable with H2O than 9NAnt and NF3. More specifically, Eint corresponding to one water molecule with one pollutant (4NP, 2NP, 9NAnt, NF3) is −0.473, −5.580, +0.588, and +8.307 kJ/mol, respectively. The Connolly surface was calculated to gain a better understanding of the volume and surface accessibility of ZIF-8, which helps to predict and support CASTEP results. Finally, an isotherm study was conducted using a Monte Carlo simulation, which proved useful in interpreting the most probable mechanism of the competing mixed capture. The results obtained were similar to those provided by Density Functional Theory (DFT)
Compact CPW-fed Antenna with Controllable WLAN Band-rejection for Microwave Imaging
No full textThis work presents the design and experimental validation of a compact frequency-reconfigurable coplanar waveguide (CPW)-fed ultra-wideband (UWB) antenna for application in microwave imaging systems with a capability to switch between UWB modes, with and without WLAN band-notched features. The suggested topology and design process are used to achieve an enhancement in the bandwidth using T-shaped slots between the feedline and the ground plane of the antenna, whereas the WLAN band is rejected using an open loop resonator (OLR) placed on the antenna backside. Switching between UWB with and without WLAN band-notched modes is performed using a single PIN diode. The simulation results corroborate well with the experimental data and clearly show an interesting frequency reconfigurable behavior for use in microwave imaging applications. The antenna performance simulation and analysis model is presented for breast tumor detection
Étude et analyse d’un réducteur de vitesse : applications aux équipements pétroliers
No full text66 p. : ill. ; 30 cmLe calcul des arbres est très important, soit au niveau de conception ou au niveau de vérification. Les éléments de transmission (poulies, engrenages, volants…) sont fixés sur les Arbres, ce qui provoque des sollicitations complexes (traction, torsion, flexion…) dans ce dernier. Pour cela le calcul du diamètre de l'arbre est très important pour supporter ces types de sollicitations, ainsi que l'emplacement des éléments de transmission doit être bien déterminé. Le travail qu’on a effectué dans ce mémoire est basé sur le dimensionnement et la vérification de la sécurité de l’arbre de la boite de vitesse du treuil Oil Well 840-E à l’aide de MATLAB et SolidWorks
البحث اللغوي محاضرات في منهجية البحث اللغوي - موجهة لطلبة السنة الثالثة ليسانس نظام ل م د/ تخصص لسانيات عامة مقياس منهجية
No full textClassification of Surface Defects in Steel Sheets Using Developed NasNet-Mobile CNN and Few Samples
No full textRolled steel is a major product of ferrous metalworking. It is a popular metal structure construction technology. Though a big amount of the finished product may be flawed, the process of manufacturing must be improved. It is critical to correctly classify hot-rolled strip faults. As a result, in recent years, numerous machine-learning-based automated visual inspection (AVI) systems have been created. However, these approaches lack several critical components, such as insufficient RAM, which causes complexity and slowness during implementation. Long execution durations, in general, cause the process to be delayed or completed later than expected. A shortage of faulty samples is also a significant difficulty in steel defect detection, as the imbalance between the huge number of non-defective photos and the defective ones causes the algorithm to be unfair in categorization. To address these three issues, a deep CNN model is created in this study. The backbone architecture is a pre-trained NasNet-Mobile that has been fine-tuned with particular parameters to be compatible with the required data. Despite having 27 times less data than other articles' datasets, the model detects steel surface photos with six defects with 99.51% accuracy, exceeding earlier methodologies. This study is useful for surface fault classification when the sample size is small, the software is not quite as effective, or time is limited. Avoiding these issues will help the steel industry improve safety and end product quality while also saving time and money
مقاربة سيميائية تأويلية لرقميات : منعم الأزرق
No full text338 ص. ، 30 سميعد الأدب الرقمي وجها من الأوجه التي لمحت بها موجة الحداثة، وما صاحبها من تطورات وتوجهات، سواء على المستوى الفكري أو الإجتماعي، أو السياسي...
وبالتالي وجدنا أنفسنا أمام أدب يمزج في ذاته بين عناصر عديدة متآلفة ومختلفة في الآن نفسه، ليعكس هذا الأخير توجها فكريا خاصا بصاحبه، يخالف كل المبادئ والأسس المتعارف عليها سابقا، وليحقق مبدأ المزاوجة بين الفنون، وكذا المزاوجة بينما هو إنساني محذ يحمل الشعور والإحساس، وبين ماهو تقني تكنولوجي، ليسقط بذلك الجمود عن الآلة والتقنية ويبث في ثناياها حياة النص وأحاسيسه، حتى يظهر في حلة مغايرة تتسم بالجدة والابتكار.
ومختلف المكونات النصية، التي حققت للصورة البصرية مكانة لا غنى عنها في الإبداع الرقمي، والتي أبهري عين المتلقي قبل فكره وإحساسه، حيث سبح هذا الأخير في فضاءه الإفتراضي، الذي حقق حرية أكبر تفوق الفضاء الواقعي المحدود.
تعد النصوص الرقمية للشاعر الرقمي "منعم الأزرق" نموذجا لما تم التحدث عنه، ضمن مقولة حرية التعبير والتفكير والإبداع، وتحقيق ماكان يعتد باستحالته في مجال الأدب، هكذا ساهمت القصيدة الرقمية في تغيير الأسس الإبداعية، مما أثر هو الآخر في أسس التلقي، والتأويل والتحليل إن صح القول، حيث أصبح النص الرقمي فضاء وعالما يسبح في مجاله اللامحدود عديد العناصر والفنون وتبعا لهذه الخصوصية تناهلت الدراسات والقراءات المتعددة لهذا النوع الأدبي الذي يعتبر جديدا من نوعه، فجربت عليه مختلف المناهج والقراءات، علها تحيط بمكنوناته وجميع دلالاته لكن النص الرقمي كان أبعد بكثير عن مرامي النقاد، إذ أنه يتطلب نقدا خاصا به، نظرا لخصوصيته الإبداعية، وكل ماتم التوصل إليه في مجال النقد، لا يعدو إلا أن يكون مجرد اجتهادات وقراءات، تعكس رؤية أصحابها، النابعة من ذوق جمالي خاص وعلاقة تفاعلية تربطهم بهذا المولود الجدي
A Bandpass Filter with Triple-Narrow Notch Bands Based on Metamaterials SRR Configurations for UWB Applications
No full textThis paper presents a bandpass filter (BPF) with three narrow notched bands designed for ultra-wideband (UWB) applications. Initially, a basic UWB BPF is designed using a microstrip multimode resonator (MMR) with an open stepped impedance stub loaded at its center. Following that, the Split-Ring Resonator (SRR) is used to generate a triple narrow notched band, allowing undesired signals to be rejected. The frequency range is 2.81 GHz to 10.2 GHz. Beyond this range, there is a strong rejection. Notably, three narrowly notched bands at 5.29, 5.83, and 7.99 GHz are used to achieve in-band interference cancellation, with - 3dB fractional bandwidths of 2.64%, 2.91%, and 1.77%, and rejection levels of -17.15 dB, -11.65 dB, and -11.56 dB, respectively. This filter simultaneously has three main advantages: it is simple, rejects unwanted signals within the bandwidth without affecting the adjacent signals, and achieved high selectivity, the simulation and measurement results show a good agreement, demonstrating effective filtering performance, with a compact dimension of 25.9 x 13.7 mm2