4,807 research outputs found

    Experimental Characterisation of GLass Aluminum REinforced (GLARE™) laminates

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    Fibre metal laminates such as GLARE™ have found promising application in the aerospace industry. These laminates were developed at the structures and materials laboratory of Delft University of Technology, Netherlands. GLARE™ is a material belonging to the family of Fibre Metal Laminates consisting of thin aluminum layers bonded with unidirectional S2-Glass fibres with an adhesive. Aluminum and S2-Glass when combined as a hybrid material can provide best features of the both metals and composites. These materials have excellent fatigue, impact and damage tolerance characteristics and a lower density compared to aluminum. GLARE™ has found major application in front and aft upper fuselage, leading edges of empennages of advanced civil aircrafts like A380. This document looks into the evaluation of two configuration of GLARE™ for its mechanical and impact characteristics. The mechanical characterisation was carried out for tensile, compression, Flexure, ILSS, Open Hole Tension, Open Hole Compression and Shear (Iosipescu). The impact behaviour were characterised based on a low velocity drop weight impact carried on these laminates. The study shows that the basic properties evaluated were more dictated by the property of the S2-Glass used. The studies show that GLARE™ laminates posses’ high impact damage resistance compared to other composite material. All the test datas generated for this study will be brought out in this document

    Tetramethylguanidine (TMG)-catalysed Synthesis of α-Aminophosphonates by a One-pot Reaction

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    Aldimines (Schiff’s bases) undergo nucleophilic addition with diethyl/dimethyl/diphenylphosphite (Pudovik reaction) in the presence of a catalytic amount of tetramethylguanidine (TMG) at ambient temperature to afford the corresponding α-aminophosphonates in high yields. The Schiff’s bases were prepared by reacting cinnamaldehyde with substituted amines in refluxing absolute alcohol. The structures of the title compounds were established by elemental analysis and IR, 1H, 13C, 31PNMR and FAB mass spectral data. The antimicrobial activities of these compounds were evaluated and they exhibited significant antimicrobial activity.KEYWORDS: Imines, α-aminophosphonates, tetramethylguanidine (TMG), dialkyl- and arylphosphites, antimicrobial activity

    Infrared and Structural Studies of Micro and Nano-crystalline Ta Doped Lead Zirconate Titanate Ceramics

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     In this paper, influence of additives on structural properties of Tantalum (Ta) doped PZT ceramics, prepared by solid-state oxide and mechanical activation (MA) routes, has been studied. The Fourier transformation infrared spectroscopy (FTIR) studies, are done to understand the structural interactions, confirmed that the wave number and bond energy decreases with the increase in Ta content accompanied by decrease in grain size. FTIR spectrum becomes broader in nanocrystalline Ta-PZT. The fraction of tetragonal phase decrease along with reduction in grain size as the Ta content increase. The remnant polarisation and coercive field also follows the similar trend on Ta doping. It is seen that infrared spectroscopy results corroborate the structure and ferroelectric properties of PZT materials

    A Research and Strategy of Remote Sensing Image Denoising Algorithms

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    Most raw data download from satellites are useless, resulting in transmission waste, one solution is to process data directly on satellites, then only transmit the processed results to the ground. Image processing is the main data processing on satellites, in this paper, we focus on image denoising which is the basic image processing. There are many high-performance denoising approaches at present, however, most of them rely on advanced computing resources or rich images on the ground. Considering the limited computing resources of satellites and the characteristics of remote sensing images, we do some research on these high-performance ground image denoising approaches and compare them in simulation experiments to analyze whether they are suitable for satellites. According to the analysis results, we propose two feasible image denoising strategies for satellites based on satellite TianZhi-1.Comment: 9 pages, 4 figures, ICNC-FSKD 201

    Xanthine oxidase activity during transition period and its association with occurrence of postpartum infections in Murrah buffalo (Bubalus bubalis)

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    The aim of this study was to quantify xanthine oxidase (XO) levels during the transition period in Murrah buffalo (Bubalus bubalis) and determine its association with certain postpartum infections. For this, six healthy buffaloes were selected from the National Dairy Research Institute (NDRI) herd and managed under standard managemental practices as followed at the institute. Blood samples were drawn weekly from each buffalo from day -21 to +21 relative to parturition by jugular vein puncture. Additional blood samples were collected from buffaloes suffering from metritis (n=5), endometritis (n=6) and mastitis (n=8) on alternate days. XO activity followed a defined pattern with values gradually declining from day -21 up to the day of calving followed by an increase to day +21, but the difference was statistically not significant between pre- and post-partum stages. The activity significantly declined on the day of calving when compared to the pre-partum mean value (p<0.05). The activity was significantly enhanced in buffaloes with bacterial infections, endometritis, and mastitis compared to healthy controls (p<0.05). However, the levels were not significantly altered among buffalo with metritis. The results indicate that increased XO activity during the postpartum period was associated with some bacterial infections in buffaloes, which could be due to increased phagocytic activity as a part of the innate defense system.Keywords: Xanthine oxidase, transition periodAfrican Journal of Biotechnology Vol. 12(32), pp. 5101-510

    Synthesis of Dinaphtho-dioxaphosphocin-8-oxides, Epoxides and Bisphosphonates

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    Preparation of 8-substituted-16H-dinaphtho [2,1-d:1’,2’-g] [1,3,2] dioxaphosphocin 8-oxides (5a–g) with an eight-membered phosphorus heterocyclic system (2) and their epoxides and bisphosphonates was accomplished by reacting 8-bromo-dinaphthophosphocin (2) with different mono and bis Grignard reagents (3a–g and 6) followed by oxidation with H2O2. Their structures were confirmed by elemental and spectral (1H, 13C and 31P NMR) data analysis. Some of these compounds are found to possess moderate antimicrobial activity.KEYWORDS: Dioxaphosphocin 8-oxides, dioxaphosphocin bisphosphonates, antimicrobial activity

    Identifying influential nodes for smart enterprises using community structure with Integrated Feature Ranking

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    Finding influential nodes reshuffles the very notion of linear paths in business processes and replaces it with networks of business value within a smart enterprise system. There are many existing algorithms for identifying influential nodes with certain limitations for applying in large-scale networks. In this paper, we propose a community structure with an Integrated Features Ranking (CIFR) algorithm to find influential nodes in the network. Firstly, we use the community detection algorithm to find communities in the system and then we rank the nodes of network based on three factors, namely- local ranking, gateway ranking, and community ranking, collectively termed as integrated features. Our algorithm intends to select influential nodes, which are both globally and locally optimal, leading to overall high information propagation. We perform the experimental results on total eight networks using various evaluation parameters. The obtained results validate superior performance against contemporary algorithms adding value to smart enterprises

    Topical Anesthetic Gel Interferes with Antibacterial Efficacy of Povidone-Iodine Both In Vitro and In Vivo

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    Purpose: To evaluate the effects of viscous lidocaine gel on the antimicrobial efficacy of povidone-iodine (PI) and their order of application in both in vitro and in vivo models. Methods: In vitro antibacterial effects were tested against Staphylococcus aureus (S. aureus) with disc diffusion methods for application of lidocaine alone, PI alone, PI before lidocaine, and lidocaine before PI. Zones of inhibition were measured after incubation at 37°C overnight. Mouse eyes were colonized with S. aureus for in vivo study to which PI and/or lidocaine were applied in various combinations. Eyes were then rinsed with saline, and the runoff fluid was collected, diluted, and plated on agar. Viable bacterial estimation was performed after incubation overnight at 37°C. Results: In vitro studies demonstrated a significantly smaller (PP\u3e0.05). In vivo studies showed that mouse eyes treated with lidocaine prior to PI had significantly more (PS. aureus growth compared to eyes that had PI applied prior to lidocaine. Conclusions: Both in vitro and in vivo studies demonstrated that lidocaine gel interfered with PI’s antiseptic properties when placed between the surface and PI. Our results are consistent with previous in vitro studies and provide greater evidence for applying PI before lidocaine gel if a viscous anesthetic agent is used

    Association of serum nitric oxide, free beta human chorionic gonadotropin and body mass index in first trimester pregnancy

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    Background: Pregnancy is a state of oxidative stress which arises from increased placental mitochondrial activity and production of reactive nitrogen species mainly nitric oxide (NO). NO is a potent vasodilator, which have pronounced effects on placental function which includes proliferation and differentiation of trophoblast. Human chorionic gonadotropin (hCG) is secreted by the syncytiotrophoblas. During pregnancy, free βhCG level can be first detected in maternal blood from 11th day after conception. Increased in NO synthesis acts as endocrine modulator of the placenta which promote secretion of free β hCG. The objective of this study was to estimate and compare the levels of βhCG and NO with different groups of BMI of pregnant women in first trimester.Methods: The study group comprises of 85 pregnant women within the age of 20-40 years with singleton pregnancy (11th-13th week + 6 days of gestation) who came for routine first trimester screening. Serum levels of free β hCG was analyzed by electrochemiluminiscense. NO was measured by kinetic cadmium reduction method. Statistical analysis used: data was expressed as mean±SD and median. Comparisons between different groups of BMI were done using Kruskal Wallis test.Results: There was significantly increased level serum NO with the increase in BMI and significantly decrease in serum levels of (p>0.05) free βhCG. We found significant positive correlation between NO and βhCG (p>0.05, r value 0.01).Conclusions: Early placental formation requires high amounts of angiogenesis and vasculogenesis. Its initiation, maturation, and maintenance are of critical importance. Failure to placental formation can lead to preeclampsia and/or intrauterine growth restriction (IUGR)

    Impulse Buying in the Digital Age: A Dimensional Study on Influencer Marketing Impact on Millennials

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    This study explores the relationship between influencer characteristics, consumer emotions, and self-construction in the context of impulse buying among millennials in the digital age. It examines how specific traits and qualities of influencers influence millennials' emotions and shape their self-identity during the process of impulse buying. The research investigates the dimensions of influencer marketing that have the most significant impact on millennials' emotional responses and their construction of self-image. By analysing the interplay between influencer characteristics, consumer emotions, and self-construction, this study provides valuable insights into the underlying mechanisms driving impulse buying behavior among millennials in the digital era. The results provide new insight into the power of influencers to sway customer behavior and suggest ways in which businesses may more successfully employ influencer marketing to connect with and convert young buyers
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