36 research outputs found

    Optimization of delamination resistance of vacuum infused glass laminate aluminum reinforced epoxy (GLARE) using various surface preparation techniques

    Get PDF
    GLARE (glass-reinforced fibre–metal laminate ) is aluminum based material of fiber metal laminate (henceforth FML) that is often fabricated by expensive autoclave procedure. In this study, the process of Injected Molding or (also known as VARTM was employed as a cost-effective alternative to produce GLARE. Several aluminum surface preparation procedures are applied to improve the interlaminar shear strength. A T3 temper 2024 aluminum alloy with 1*1 plain fabricated glass fabrics were used to make GLARE composites. GLARE consists of two aluminum sheet as external layer and glass fabric as internal layers. Four sets of aluminum sheets were prepared, one unanodized and three other anodized. Three different anodizing procedures (constant voltage mode, increasing voltage mode and decreasing voltage mode) have been adopted in this research. Two types of curing treatments were applied on VARTM fabricated specimens. According to ASTM D1876 T-peel test standard, the sets of prepared specimens have been tested to examine the adhesive bonding strength and fracture toughness of mode-I. The obtained results which include force-displacement curves, peak loads and fracture toughness were showed that a significant improvement for anodized specimens with all voltage modes. The first curing treatment offered better results than second curing treatment. The best improvement was obtained from anodized specimen with decreasing voltage mode cured by the first treatment which reaches to six times the results obtained from unanodized specimen. The delamination behavior for this specimen was verified numerically

    Reactivity of O-Drug Bond in some Suggested Voltarine Carriers: Semiempirical and ab Initio Methods

    Get PDF
     تمت مناقشة إمكانية استخدام مادة حاملة مقترحة جديدة (D) لعقار ديكلوفيناك (فولتارين) باستخدام حسابات ميكانيكا الكم. تم استخدام طرق الحساب (PM3) و (DFT) لتحديد مسار التفاعل لطاقات كسر الرابطة (O-Drug). تم استخدام مجموعات مختلفة الأدوية كحاملات لعقاقير أولية من ديكلوفيناك (في الفراغ كوسط تفاعل) عند الشكل الهندسي التوازني. تضمنت الحسابات التركيب الهندسي وبعض الخواص الفيزيائية، بالإضافة إلى السمية والنشاط البيولوجي وخصائص NLO للدواء مع حوامله، والتي درست باستخدام طريقة HF. تم إجراء العمليات الحسابية بواسطة برنامج .Gaussian 09 تم إجراء المقارنة بين الطاقات الكلية للمواد المتفاعلة وطاقات التنشيط والحالات الانتقالية إلى الحالة النهائية. تهدف العقاقير الأولية المقترحة إلى تحسين خصائص حوامل الديكلوفيناك والحصول على بدائل جديدة للناقلات المعتمدة نظريا.In this work, the possibility to use new suggested carriers (D= Aspirin, Ibuprofen, Paracetamol, Tramal) is discussed for diclofenac drug (voltarine) by using quantum mechanics calculations. The calculation methods (PM3) and (DFT) have been used for determination the reaction path of (O-D) bond rupture energies. Different groups of drugs as a carrier for diclofenac prodrugs (in a vacuum) have been used; at their optimized geometries. The calculations included the geometrical structure and some of the physical properties, in addition to the toxicity, biological activity, and NLO properties of the prodrugs, investigated using HF method. The calculations were done by Gaussian 09 program. The comparison was made for total energies of reactants, activation energies, and transition states to final products. The suggested prodrugs aim to improve the diclofenac carrier's properties and obtain new alternatives for the approved carriers theoretically

    Performance Evaluation of Roughened Solar Air Heaters for Stretched Parameters

    Get PDF
    Artificial roughness applied to a Solar Air Heater (SAH) absorber plate is a popular technique for increasing its total thermal efficiency (ηt−th). In this paper, the influence of geometrical parameters of V-down ribs attached below the corrugated absorbing plate of a SAH on the ηt−th was examined. The impacts of key roughness parameters, including relative pitch p/e (6–12), relative height e/D (0.019–0.043), angles of attack α (30–75°), and Re (1000–20,000), were examined under real weather conditions. The SAH ηt−th roughened by V-down ribs was predicted using an in-house developed conjugate heat-transfer numerical model. The maximum SAH ηt−th was shown to be 78.8% as predicted under the steady-state conditions of Re = 20,000, solar irradiance G = 1000 W/m2, p/e = 8, e/D = 0.043, and α = 60. The result was 15.7% greater efficiency compared to the default smooth surface. Under real weather conditions, the ηt−th of the roughened SAH with single- and double-glass covers were 17.7 and 20.1%, respectively, which were higher than those of the smooth SAH

    Abaqus Simulation of the Fire's Impact on Reinforced Concrete Bubble Deck Slabs

    Get PDF
    The use of Bubble Deck in modern prefabricated construction methods has recently become widespread in industrial projects worldwide. In the middle of a typical slab, Bubble Deck places hollow plastic balls that do not improve structural performance but significantly reduce structural weight. This study analyzes the behavior of self-uniting bidirectional concrete slabs with plastic spherical voids under high temperatures and for different periods. Six simply supported bidirectional plates, five of which contained bubbles and one solid, were numerically tested using the finite element method and the commercial ABAQUS software to investigate the behavior of bidirectional plates fired at various temperatures and for various amounts of time. Each slab has the following measurements: (1500*1500*150) mm. These slabs were fired at different temperatures (600 and 800) °C and for different periods (one and two hours). The slabs were classified into four groups depending on the kind of slab (solid or bubble), the degree of burning (600 and 800) °C, and the duration of the burning (one and two hours). The loading strength of concrete was found to be up to 65% less than the maximum capacity of a slab that was bubbled and fired at high temperatures. The length of the firing time also had a significant effect on reducing the strength of the concrete. The longer the firing period, the lower the load resistance of the concrete. The ball would melt and scorch in an intense, protracted fire without noticeable effects. The ability of the steel to maintain adequate strength during a fire, when it will be burned and lose significant strength as the temperature rises, determines the slab’s ability to withstand fire. Bubble deck slabs produce between 17% and 39% stronger thermal resistance than an equivalent solid slab of the same depth, even though they are not intended to provide thermal insulation due to the encapsulation of the air bubbles within the center of the concrete slab

    I-V Characteristics of ITO/CdTe/Al 2 O 3 /Si/Au Thin Film Solar Cell

    Get PDF
    Abstract The (1.7, 3.5, and 4.5n

    Determination of total antioxidant content of methanolic extracts of Cynara scolymus, Echinacea purpurea and Portulaca oleracea

    Get PDF
    Background: The unique properties of medicinal plants particularly their effects on human health have attracted the attention of many researchers. The antioxidant properties of medicinal plants is a strong reason to use them in the food and pharmaceutical industries. Hence, the aim of this study was to evaluate the antioxidant properties of methanolic extracts of Cynara scolymus, Echinacea purpurea   and Portulaca oleracea. Aerial parts of C. scolymus, E. purpurea and P. oleracea were dried and ground.Methods: Then, plant samples were prepared using homogenizing plant powders in methanol solution. Finally, the total   antioxidant capacity of the plants was assessed by ferric iron reducing antioxidant power (FRAP) assay.Results: The results revealed that the total antioxidant capacity was found as 3.45, 1.16 and 1.68 mmol Fe2+/L for C. scolymus, E. purpurea and P. oleracea, respectively. Based on our results, C. scolymus, E. purpurea and P. oleracea showed a potent antioxidant activity.Conclusion: It is recommended that utilization of C. scolymus, E. purpurea and P. oleracea in food and pharmaceutical industries could possibly possess beneficial health effects.Keywords: Antioxidant Activity; Medicinal Plants; Cynara scolymus; Echinacea purpurea; Portulaca oleracea    

    A Deep Learning Algorithm for Lung Cancer Detection Using EfficientNet-B3

    Get PDF
    Lung carcinoma is one of the main causes of deaths over the whole world, causing a global burden of morbidity and mortality. Detecting lung tumors at their early stages can help reducing the risk of having lung cancer. This paper proposes a deep learning algorithm using EfficientNet B3 for lung cancer detection. The purpose is to improve detection accuracy highlighting potential to revolutionize the field of medical imaging and improve patient care. The proposed approach is build based on EfficientNet B3 model to classify four different types of lung cancer. The approach used CT scan images labeled into Normal, Squamous.cell.carcinoma, Large.cell.carcinoma, and Adenocarcinoma for the purpose of lung cancer detection. The results showed that the proposed model provided an improvement rate of 2.13% compared with the best-trained classifier with accuracy of 96%. This model can be generalized to improve lung cancer detection. The finding of deep neural networks, particularly EfficientNet B3, in supporting the diagnosis and detection of the lung disease, particularly in its early times

    Dietary Dracocephalum Kotschyi Essential Oil Improved Growth, Haematology, Immunity and Resistance to Aeromonas Hydrophila in Rainbow Trout (Oncorhynchus Mykiss)

    Get PDF
    In the present study, the effect of Dracocephalum kotschyi essential oil (DKE) was investigated on growth, haematology, immune and antioxidant defence system and resistance of rainbow trout juveniles to bacterial infection (Aeromonas hydrophila). For this purpose, the fish were fed a diet containing different concentrations of DKE including 0 (control), 0.2, 0.25 and 0.3 mg/kg diet in three replicates for 60 days. After feeding trial, the fish were challenged with a pathogenic dose of A. hydrophila. Based on the results, immune components in plasma (alternative complement activity [ACH50], IgM content, lysozyme activity, total protein and total albumin) and mucus (protease activity, IgM content and lysozyme activity) significantly elevated in fish fed diet containing 0.2 and 0.25 mg DKE/kg diet compared with other groups (p < 0.01). The plasma bactericidal activity increased in all DKE-supplemented fish. Supplementation of fish with 0.3 mg DKE/kg diet depressed the mucosal lysozyme activity and IgM content. The liver antioxidant enzymes, glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) showed increased activity in response to 0.25 and 0.3 mg DKE/kg diet compared with other experimental diets (p < 0.01). Dietary DKE changed the haematology of the fish. The haematocrit, red blood cell count (RBC), white blood cell (WBC), haemoglobin content and mean erythrocyte cell haemoglobin content (MCHC) increased in response to DKE. In contrast, the mean corpuscular haemoglobin (MCH) decreased in fish fed 0.2 and 0.25 mg DKE/kg diet compared with other diets (p < 0.01). The supplementation of fish with 0.2 and 0.25 mg DKE/kg diet decreased the expression of cytokine-related genes, TNF-α and IL-8. In contrast, the DKE up-regulated the expression of the immune-related genes, C3 and lysozyme. DKE at concentration of 0.3 mg/kg diet depressed the C3 and lysozyme gene expressions. The DKE supplementation decreased the mortality rate of the fish after bacterial challengecompared with non-supplemented ones (p < 0.01). In conclusion, the findings of this study revealed the immune-stimulating effects of DKE at optimized dietary concentrations. In addition, DKE decreased the mortality induced by A. hydrophila infection

    Abaqus Simulation of the Fire's Impact on Reinforced Concrete Bubble Deck Slabs

    No full text
    The use of Bubble Deck in modern prefabricated construction methods has recently become widespread in industrial projects worldwide. In the middle of a typical slab, Bubble Deck places hollow plastic balls that do not improve structural performance but significantly reduce structural weight. This study analyzes the behavior of self-uniting bidirectional concrete slabs with plastic spherical voids under high temperatures and for different periods. Six simply supported bidirectional plates, five of which contained bubbles and one solid, were numerically tested using the finite element method and the commercial ABAQUS software to investigate the behavior of bidirectional plates fired at various temperatures and for various amounts of time. Each slab has the following measurements: (1500*1500*150) mm. These slabs were fired at different temperatures (600 and 800) °C and for different periods (one and two hours). The slabs were classified into four groups depending on the kind of slab (solid or bubble), the degree of burning (600 and 800) °C, and the duration of the burning (one and two hours). The loading strength of concrete was found to be up to 65% less than the maximum capacity of a slab that was bubbled and fired at high temperatures. The length of the firing time also had a significant effect on reducing the strength of the concrete. The longer the firing period, the lower the load resistance of the concrete. The ball would melt and scorch in an intense, protracted fire without noticeable effects. The ability of the steel to maintain adequate strength during a fire, when it will be burned and lose significant strength as the temperature rises, determines the slab’s ability to withstand fire. Bubble deck slabs produce between 17% and 39% stronger thermal resistance than an equivalent solid slab of the same depth, even though they are not intended to provide thermal insulation due to the encapsulation of the air bubbles within the center of the concrete slab
    corecore