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In continuation of our reserach for synthesizing heterocyclic derivatives with a broad range of biological activities, the current research was performed to synthesize 3β-hydroxypregn-5-ene-20-one derivatives of coumarin, isoxazole, pyrazole, pyridine and pyrimidine and screen for antitumor activity. Synthesis of amino-thiopephen derivatives (1a-1b) was performed through reaction of 3β-hydroxypregn-5-ene-20-one with ethyl cyanoacetate or malononitrile and sulphur. 3β-Hydroxypregn-5-ene-20-one was reacted with ethyl cyanoacetate in the presence of hydrazine, urea or thiourea to obtain aminopyrazole (3), aminopyrimidine (4a-4b) derivatives, respectively. The amino-thiophene derivatives (1a-1b) further reacted with either phenylisothiocyanate or benzoylisothiocyanate to form fused thienopyrimidine derivatives (5a-5d). The products 1a and 1b were also treated with ethyl cyanoacetate to afford cyanoacetamidothiophene derivatives (6a-6b) which were converted to fused thienopyridone derivatives (7a-7b) through cyclization reaction. The compounds 6a and 6b were allowed to react with different carbonyl compounds including salicyaldehyde, cyclopentanone-sulphur mixture, acetylacetone and malonaldehyde to prepare coumarin (8a-8b), cyclopentylthiophene (9a-9b) and 2-pyridinone (10a-10d) derivatives respectively. Furthermore, the reactions of hydroxylamine hydrochloride and benzoylacetonitrile with the compounds 6a-6b separately afforded new aminoisoxazole (12a-12b) and phenylpyridone (14a-14b) derivatives, respectively. The structures of new products were established through IR, 1H NMR, 13C NMR spectroscopic and mass spectrometric analysis. The synthesized compounds (1a-1b to 14a-14b) displayed in-vitro antitumor activity against human cell-lines, including MCF-7 (breast adenocarcinoma), SF-268 (CNS cancer) and NCI-H460 (non-small lung cancer cell). The results suggested that all the screened products exhibited cell growth inhibitory activity in a dose-dependents manner. However, the compound 12a showed highest level of inhibition against all three cell-lines.

In this paper, a solar photovoltaic model integrated with brushless DC motor via DC to DC zeta converter is controlled in two stage. In first stage, a fuzzy rule based maximum power point tracking (PPT) is proposed to generate the pulse for DC to DC zeta converter. It is efficient intelligent control approach to extract maximum power from the solar PV system and enhance the speed to track the maximum power. The basic three process of fuzzy logic controller (FLC) are fuzzifier, inference and defuzzifier where the defuzzification process is used center of gravity (COG) method to convert its original value. The FLC to extract maximum PPT for solar PV based brushless DC motor can be examined the performance under transient and dynamic condition with different solar insolation. Moreover, in second stage a trapezoidal control approach based electronic commutation is chosen to generate the pulses of voltage source inverter (VSI) and it offers the smooth control of the brushless DC motor which can easily applicable for water pumping or irrigation purpose. A second stage, trapezoidal control approach is close loop control algorithm using sensorless drive. The performance of proposed fuzzy rule based control algorithm is shown using simulation results on MATLAB platform.

Purpose: To develop effective cancer chemopreventive and anti-inflammatory agents, a series of chalcones were prepared by reacting suitable aromatic aldehyde with appropriate acetophenones. Methods: Twenty-four synthesized chalcones (namely, 1 - 24) were assessed for their in vitro anti-cyclooxygenase-1 (COX-1) and anti-cyclooxygenase-2 (COX-2) activity in a COX catalyzed prostaglandin synthesis bioassay. Molecular docking was done to investigate the ligand-protein interactions, and selectivity on both enzymes. ADMET (absorption, distribution, metabolism, excretion, toxicity) modeling and software were also used. Results: The compounds inhibited both COX-1 and COX-2. Two compounds (3 and 19) demonstrated more marked COX-2 inhibition than compound 1. Indomethacin as a standard anti-cyclooxygenase shows unselective inhibition of 81.44 ± 6.5 and 91 ± 9.5, respectively. The in silico data revealed that a chalcone skeleton with C=O at 4-position, C2–C3 double bond and OH at 5-position are necessary properties for anti-cyclooxygenase effects. It was also revealed that the propenone moiety comprises of an appropriate scaffold which proposes a new acyclic 1,3-diphenylprop-2-en-1-ones with selective anti-COX effects. A molecular modeling investigations where these chalcones 1, 3 and 19 were docked in the active site of COX-2 depicted that the p-CH3 substituent on the C-4- phenyl ring A are oriented in the vicinity of the COX-2 secondary pocket Phe381, Gly526, Tyr385 and Val349. Conclusion: Based on the screening for oral bioavailability, in silico ADMET, and toxicity risk assessment, this study shows that these compounds could be a cornerstone for the development of new pharmaceuticals in the battle against COX-associated inflammatory disorders.

Pierre Robin syndrome/sequence (PRS) is associated with a triad of symptoms that includes micrognathia, cleft palate, and glossoptosis that may lead to respiratory obstruction. The syndrome occurs in 2 forms: nonsyndromic PRS (nsPRS), and PRS associated with other syndromes (sPRS). Studies have shown varying genetic mutations associated with both nsPRS and sPRS. The present systematic review aims to provide a comprehensive collection of published literature reporting genetic mutations in PRS. Web of Science, PubMed, and Scopus were searched using the keywords: “Pierre Robin syndrome/sequence AND gene mutation.” The search resulted in 208 articles, of which 93 were excluded as they were duplicates/irrelevant. The full-text assessment led to the further exclusion of 76 articles. From the remaining 39 articles included in the review, details of 324 cases were extracted. 56% of the cases were sPRS, and 22% of the cases were associated with other malformations and the remaining were nsPRS. Genetic mutations were noted in 30.9% of the 300 cases. Based on the review, SOX9 was found to be the most common gene associated with both nsPRS and sPRS. The gene mutation in sPRS was specific to the associated syndrome. Due to the lack of original studies, a quantitative analysis was not possible. Thus, future studies must focus on conducting large-scale cohort studies. Along with generating data on genetic mutation, future studies must also conduct pedigree analysis to assess potential familial inheritance, which in turn could provide valuable insights into the etiopathogenesis of PRS.

A model Mistry training center (MTC) is proposed here to enhance the economic growth rate and literacy rate of the rural and urban areas. It is based on a teacher, Mistry, and eduworker. This is a combination of school and small industries into a single educational setting. In this model, the teacher teaches the general course whereas Mistry means a technical person who has skill in particular fields. Moreover, eduworker means students who take education with part-time work. This model is developed an algorithm to understand basic three mode such as primary mode accomplishment (PMA), apprentice mode accomplishment (AMA), and finally, optional mode (OM) of the proposed model. While role and responsibilities of the teacher, Mistry, and eduworker are given in detail under profitable condition and non-profitable conditions, a comparative data of the per capita income, literacy rate, and gross domestic product (GDP) are presented to distinguish how the proposed model is a good option.

Resistance spot welding process (RSW) appeared widely applicable in various industries, especially for mass production. The typical applications of this process are in automobile industries, furniture, and other sheet metal industries. Resistance spot welding has been considered a successful process for welding ferrous based metal sheets. RSW process has some difficulty in welding aluminum and its alloys. Generally, aluminum alloys produce bad welds because of their physical and metallurgical properties like oxide formation, thermal expansion, thermal contraction, less weldability, and formation of IMC's. The present study targets the feasibility evaluation and mechanical characterization of RSW welds on AA5083alluminum alloys. Optimum input process parameters were identified for welding of 2.5 mm thick Al sheets, and three output variables were analyzed, i.e., Tensile strength, joint hardness, and nugget diameter. It was observed that joint strength was significantly improved by increasing the process parameters. The fair welds with 227kN tensile strength were produced at the parameters3000N electrode pressure, welding current 8KA and 15 weld cycle time. These input parameters also gave the moderate diameter of the nugget, which is equal to 7.61 mm and low(preferable) average hardness in the nugget, i.e., 101Hv. The weld nugget diameter has a significant effect on the process parameter. It has been seen that the increase in process parameters, i.e., weld cycle time, the pressure of the electrode and welding current, results in the increment in weld nugget size. The maximum sizes of the nugget diameter and weld strength were observed with sample number 9, which is 7.94 mm and 231kN. The strength of the welds is significantly low compared with the base metal. However, it has been observed that the welding of 2.5 mm thick AA5083 aluminum sheets by RSW is possible and might be acceptable for lightweight applications.

Advanced composite patching has been used to rehabilitate cracked structures. In this work, the effects of bonded carbon fiber-reinforced polymer (CFRP) patch on reducing the crack tip driving forc...

The Fuel cells are probable to rapidly develop a source of low to zero-emission power generation for applications in portable technologies, electric and rechargeable automobiles. This is the matter of concern for renewable energy that is attractive and noteworthy owing to growing power demand. The uncertainty of the increasing oil values and eco-friendly difficulties will be the prime concern in future. Amongst the several renewable energy sources fuel cell is the advance alternative energy solution and it is attaining more popularity by virtue of its advanced effectiveness, purity and cost-effective source of power. Hence, this book chapter presents a comprehensive review of the design and fabrication of nanostructured material for fuel cell application. In accumulation, thorough metal-metal oxides fabrication and effective role of fuel cell in energy-related issues. This chapter also focuses on the working principle, its advantages, disadvantages, in transportation, industrial and commercial applications of fuel cell.

Parameters evaluation, design, and intelligent control of the solar photovoltaic model are presented in this work. The parameters of zeta converters such as a rating of an inductor, capacitor, and switches for a particular load are evaluated its values to compare the trade of the existing model and promoted to research in the proposed area. The zeta converter is pulsed through intelligent controller-based maximum power point tracking (intelligent-MPPT). The intelligent controller is a fuzzy logic controller (FLC) which extracts maximum power from the solar panel using the zeta converter. The performance of evaluated parameters based on the solar system and zeta converter is seen by an intelligent control algorithm. Moreover, evaluated parameters of solar photovoltaic (PV) and zeta converter can be examined the performance of fuzzy based intelligent MPPT under transient and steady-state conditions with different solar insolation. The brushless direct current motor-based water pump is used as the direct control (DC) load of the proposed model. The proposed model can enhance the research and assist to develop a new configuration of the present system.

The tensile and fatigue properties of epoxy reinforced with 68 volume percent carbon fiber, CFRP, have been fully investigated. The effect of the presence of an open circular hole on tensile, fatigue residual strength, and fatigue strength of CFRP plates was studied experimentally and numerically. The results of pin bearing, i.e. bolt-loaded holes, tests were also investigated and evaluated. A three-dimensional orthotropic-elastic finite element code was developed to calculate the stress concentration factors of open circular holes or bolt-loaded holes in composite materials. The modulus of elasticity, tensile strength, and maximum elongation of CFRP are approximately equal to the values found in the technical data sheet of the supplier. A rule of mixtures type relation is adequate to predict the modulus of elasticity of such CFRP plate. This may be attributed to the high mechanical properties and high volumetric content of the fibers compared with the matrix, i.e. there is a marginal contribution of the strength of the matrix or the fiber-matrix interfacial bond strength. Based on the net stress analysis, there is no difference between the mechanical behavior of smooth and open-holed specimens, i.e. notch insensitivity. This is due to the incapability of the matrix to transfer the load from the discontinuous part. The same behavior was also found under cyclic loading. Due to the weakness in the bond between the fiber and matrix or in the shear strength of the matrix compared with the tensile strength of the fiber, the failure mode of all tested bolt-loaded unidirectional CFRP plates is shear-out. Further, the strength of such bolted joints is mainly dependent on the size of the contact area between the hole and the bolt.

Functionally graded materials, FGM, permit tailoring the material volume fractions to extract maximum benefit from their in-homogeneity. Such materials offer great potential for components, which operate under severe thermal or mechanical loadings, such as spacecraft heat shields, plasma facings for fusion reactors, crucial jet fighter structures and engine components. In the present work, polyester matrix reinforced by varying glass fiber distribution was used to obtain FGM polymeric composites. The hand lay-up technique was adopted to manufacture the FGM. The mixed mode crack path of glass fiber/polyester FGM under three point bend, 3PB, was observed. The mechanical properties, such as tensile and flexural strength were determined experimentally and numerically. Pre-cracks with different lengths and locations with seven different inclination angles were considered to study the mixed mode crack growth of FGM. For the same crack length, the present results showed that the maximum applied load increased with increasing the crack inclination angle, i.e. the mode of mixity increased to reach pure mode II. Generally, the crack path initiated from the original inclination angle and grew along a curvilinear trajectory to extend toward the upper loading point.

In the present work, the nano-Aluminum oxide (Al2O3), nano-Silicon Carbide (SiC), or a hybrid of them were infused into epoxy resin with an ultrasonic system with various weight percentage ratios of the nanoparticles. Small punch testing (SPT) and indirect tension testing were adopted to measure the tensile properties of the present nanocomposites. Pin-on-ring wear testing was also performed to examine wear performance of epoxy Al2O3 and SiC nanocomposites. The Finite Element Analysis method is introduced to simulate the indirect tension test and SPT to give a complete vision of the stress distribution in the nanocomposite specimen during the loading, and to examine its mode of failure. Good agreement between the numerical and experimental results was observed. The addition of nanoparticles from Al2O3 or SiC improves the wear resistance of epoxy. Furthermore, epoxy with nano-Al2O3 has a higher wear resistance than that with nano-SiC. The tensile strength and modulus of elasticity of epoxy are reduced by adding the Al2O3 nanoparticle. The synergistic effect is not observed in the present study.

Over the last decade, the assortment of metal, metal-oxide materials fabricated using several chemical and physical techniques have increased significantly. This chapter presents a notable explanation of the progressive development of the solid materials known as aerogels. Metal, metal-oxides aerogels can have unusual properties, such as, high surface area, low density, low thermal conductivity, and good optical translucency. This combination of properties makes aerogels attractive materials for use in applications ranging from lightweight structural, insulating or shock absorbing materials especially in aeronautics, microelectronics, sensing applications, and purification systems. These aerogels materials have been fabricated using extensive variability of techniques, such as, incorporation of metal nanoparticles or carbon-based substituents into the sol-gel matrix and surface modification of the matrix following gelation. This chapter presents brief introduction, basic properties, and fabrication process of metal, metal oxides aerogels, and further various techniques for the purification systems has been discussed.

Among Floating liquefied natural gas (FLNG) operations, natural gas liquefaction is the most energy intensive. Hence, to achieve energy-efficient and eco-friendly FLNG operations that can meet offshore environment requirements, a hydrofluoroolefin-based single mixed refrigerant (SMR) natural gas (NG) liquefaction process is proposed. The proposed process is optimized using a sine cosine paradigm to reduce the overall energy consumption. Then, the economic performance of the proposed process is performed and analyzed against that of the conventional LNG process. Finally, uncertainty quantification is performed to analyze the process outputs under the effects of uncertain key decision variables to guarantee operational reliability. The optimization yields an energy consumption of 0.2317 kW, resulting in a 41.73% energy saving compared to the conventional SMR process. Moreover, the total annualized cost is reduced to 26.02% owing to the appropriate mixed refrigerant selection and process design. The results of the uncertainty quantification analysis indicate that the flow rates of methane and butane, the evaporation pressure, and the condensation pressure are the most influential factors when processing energy consumption and utilizing the minimum internal temperature approach. This study highlights the importance of introducing eco-friendly refrigerants to replace conventional refrigerants used in NG liquefaction processes.

Credit cards have become an important part of the day, and they are being used in areas of payment for a range of sales or transfers from mobile or payment through electronic stores, and their frequent use has increased the rate of fraud and penetration in credit cards. Many technologies were introduced to reduce fraud and all the techniques were doing the same task, but each one has its advantages and disadvantages. In this paper, after researching and looking at the difficulties of highlighting and detecting fraud and credit card fraud, we strive to retrieve, review and mention the arrival of Yemen techniques for detecting fraud in credit cards. The characteristics, whether good or bad, are mentioned for fraud detection and comparison methods. The techniques are mentioned in two fraud detection forms, either supervised or unsupervised. We cited the findings of the experiments they had done.

Three-point bending tests on notched beams of three types of steel fiber-reinforced self-compacting concrete (SFRSCC) have been performed by using both a servo-hydraulic machine and a drop-weight impact instrument. The lo ading rates had a range of six orders of magnitude from 2.20 × 10−3 mm/s (quasi-static) to 2.66 × 103 mm/s. These SFRSCCs had the same matrix, but various types of steel fiber (straight and hooked-end) and contents (volume ratios), 0.51%, 0.77% and 1.23%, respectively. The results demonstrate that the fracture energy and the flexural strength increase as the loading rate increases. Moreover, such tendency is relatively moderate at low rates. However, at high rates it is accentuated. For the 0.51% fiber content, the dynamic increase factors of the flexural strength and the fracture energy are approximately 6 and 3, while for the 1.23% fiber content, they are around 4 and 2, respectively. Thus, the higher the fiber content the less rate sensitivity there is.