Incorporating Crystallographic Orientation in the Development of Resonant Ultrasound Spectroscopy

Resonant ultrasound spectroscopy (RUS) measures the mechanical resonance frequencies of solids and uses computational algorithm to extract a complete set of elastic constants. One of the advantages of the RUS method is its applicability to small single crystals. In the past two decades, the RUS technique has gained more acceptance as a nondestructive method to measure elastic properties. The goal of this project is to measure elastic properties of micro pillars without free-free boundary conditions and arbitrary crystallographic orientations. To achieve this goal we need a capability to measure elastic constants of single crystals with arbitrary crystal orientation relative to sample geometry. The inherent assumptions in conventional RUS algorithm include free boundary condition on the specimen faces and the faces of the specimens are normal/parallel to the principal crystallographic axes. To meet these requirements, a time consuming sample preparation, involving multiple inspections of x-ray Laue back reflection to check the crystallographic orientation, is followed. Such an intensive method is not suitable for many samples in engineering applications. To estimate the elastic constants of such samples, a new RUS algorithm has been developed that incorporates the sample crystallographic orientation expressed in terms of Euler angles. The power of the modified RUS algorithm is demonstrated by applying it to estimate the elastic constants of cubic and hexagonal crystal structure samples with known orientation. The results are compared with literature values. Potential application of the method include estimation of elastic constants and their use as input parameters in models that predicts the mechanical behavior of materials for engineering applications is discussed

Network traffic analysis for threats detection in the Internet of Things

As the prevalence of the Internet of Things (IoT) continues to increase, cyber criminals are quick to exploit the security gaps that many devices are inherently designed with. Users cannot be expected to tackle this threat alone, and many current solutions available for network monitoring are simply not accessible or can be difficult to implement for the average user, which is a gap that needs to be addressed. This article presents an effective signature-based solution to monitor, analyze, and detect potentially malicious traffic for IoT ecosystems in the typical home network environment by utilizing passive network sniffing techniques and a cloud application to monitor anomalous activity. The proposed solution focuses on two attack and propagation vectors leveraged by the infamous Mirai botnet, namely DNS and Telnet. Experimental evaluation demonstrates the proposed solution can detect 98.35 percent of malicious DNS traffic and 99.33 percent of Telnet traffic for an overall detection accuracy of 98.84 percent

PRODUCTION OF BIODIESEL FROM SOME VEGETABLE OILS

Biodiesel is becoming prominent among the alternatives to conventional petro-diesel due to economic,environmental and social factors. The quality of biodiesel is influenced by the nature of feedstock and theproduction processes employed. High amounts of free fatty acids (FFA) in the feedstock are known to bedetrimental to the quality of biodiesel. In addition, oils with compounds containing hydroxyl groups possesshigh viscosity due to hydrogen bonding. American Standards and Testing Materials, (ASTM D 6751)recommends FFA content of not more than 0.5% in biodiesel and a viscosity of less than 6 mm2/s. Thephysico-chemical properties of palm kernel oil and coconut oil were assessed for their potentials in biodiesel.The properties of palm kernel oil and coconut oil were compared with those of palm from literature whilethat of biodiesel were compared with petro-diesel, ASTM and European Standards (EN14214). Resultsshowed that high amounts of FFA in oils produced low quality biodiesel while neutralized oils with lowamounts of FFA produced high quality biodiesel. The quality of biodiesel from palm kernel oil and coconutoils was improved greatly by neutralising the crude oil

Vitamins A, C and Lycopene Contents of Some Varieties of Tomato and Pepper in the Southwest Region of Nigeria

The concentrations of vitamin A, C and lycopene were determined in some varieties of Lycopersicum esculentum (Plum tomato, Marmande tomato, Beefsteak tomato and Cherry tomato) and capsicum sp. (fresh Cayenne pepper, Bell pepper, Green pepper, Sweet pepper, Hot pepper and Dry cayenne pepper). The ethanolic extracts of the varieties of tomato and pepper were prepared and the vitamin A and lycopene contents were quantified by separating funnel technique, while the concentration of vitamin C was determined by titration technique in the aqueous extract. The concentrations of vitamin A and lycopene were significantly increased (p<0.05) in Plum and Cherry tomatoes. Vitamin A concentration in the various pepper fruits increased significantly (p<0.05) in the order: green pepper<sweet pepper=hot pepper<bell pepper< dry cayenne<cayenne. Significant increases (p<0.05) were presented only in the Vitamin C contents in the green, hot and cayenne pepper fruits with no changes (p>0.05) among these pepper. Lycopene concentrations were significant increased (p<0.05) in the order of green pepper<sweet pepper<bell pepper<cayenne pepper. The finding of the study indicated that the Plum and Cherry tomato fruits, and Bells and fresh Cayenne pepper fruits would have better anti-oxidative capabilities. Therefore, the consumption of the combination of these tomato and pepper fruits as recipes in soup or stew making may boost the endogenous anti-oxidative status. Keywords: Lycopersicum esculentum, capsicum species, Vitamin A, Vitamin C, Lycopene, anti-oxidative capabilities, recipes and boost the anti-oxidative status

Elucidation of Bioactive Compounds in Methanol Extract of Mitracarpus Vilosus Leaf using GC-MS analysis

Mitracarpus vilosus is widely used among the indegenes of Ibeju-Lekki area of Lagos State for the treatment of skin lesions. This study elucidated the phytochemical constituents in 80% methanolic leaf extract of Mitracarpus vilosus. Phytochemical screening and gas chromatography-mass spectrometry (GC-MS) analyses were carried out on the leaf extract. The qualitative analyses showed the presence of the following phytochemicals, tannins, terpenoids, saponins, cardiac glycosides and steroids. The phytochemical screen did not reveal any flavonoids. However, Squalene 14.27%, n-Hexadecanoic acid 11.60%, 2-Octylcyclopropene-1-heptanol 8.43%, Octadecanoic acid 5.45%, 1,4-Naphthalenedione 3.19% were the first five major bioactive compounds revealed by GC-MS in the leaf extract. The results of this study validated the bioactive constituents in Mitracarpus vilosus which may be the justification for its use for the treatment of skin lesions and other ailments. DOI: 10.7176/JBAH/12-14-04 Publication date:July 31st 202

Fatigue Behaviour of Medium Carbon Steel of Different Grain Structures

This paper investigated the effect of heat treatment operations on the fatigue resistance of low carbon steel. Specimens after preparation for fatigue testing were subjected to annealing, normalizing and quenching heat treatment. Results show that the annealed specimen had the largest number of cycles to failure, indicating a high fatigue resistance. The microstructure of the specimens was examined in other to corroborate the obtained property with the microstructure. When compared with the untreated specimen, the annealed specimen (with optimum fatigue resistance) shows a large grains size of pearlite which was distributed across the entire surface of the microstructure. Generally, it was found that the size and distribution of specimens’ grains affect the resistance of the low carbon steel to fatigue failure. Keywords: fatigue, low carbon steel, heat treatment, microstructur

Finite Element Modeling of Resonance in Polycrystalline Materials for Resonance Ultrasound Spectroscopy

Validation of models that predict the performance of aerospace engine materials depends on the ability to obtain accurate single crystal elastic constants. Resonance Ultrasound Spectroscopy (RUS) is a nondestructive technique in which the natural resonances of a material are utilized to obtain these constants. Traditional RUS utilizes an analytic approach to determine the resonance frequencies of a specimen given an initial guess set of elastic constants. A nonlinear optimization process then fits the elastic constants to experimentally measured data. This approach is limited both in its ability to handle specimens with complex geometry and to handle polycrystalline materials. These more complex scenarios can be approached by utilizing a finite element forward model to obtain sample resonances. A finite element forward model is being developed utilizing COMSOL Multiphysics to compute specimen resonance frequencies. Elastic constants are obtained utilizing a bounded nonlinear optimization routine in MATLAB by way of COMSOL\u27s LiveLink for MATLAB interface. Validation of this forward model has been performed on single crystal specimens, including a nickel superalloy parallelepiped and a fused silica cylinder with a chamfer, ultimately producing lower residual error after optimization than the traditional RUS approach. Model validation is also being performed on a Nickel Aluminide (NiAl) bicrystal. This paper presents the details of this validation process. Also presented is an examination of error sources and the impact they can play in the ability to accurately obtain elastic constants

INTERRELATIONSHIP BETWEEN SEED VIGOUR TRAITS AND FIELD PERFORMANCE IN NEW RICE FOR AFRICA (NERICA) GENOTYPES (Oryza sativa L.)

The study was conducted to examine the relationships between seed vigour traits and field performancein 24 interspecific rice (Oryza sativa L.) genotypes specifically for Africa. Seeds of these genotypeswere evaluated in the late cropping season of 2003 and early cropping season of year 2004 inthe laboratory for seed vigour traits. Field performances were evaluated at the Teaching and ResearchFarm, University of Agriculture, Abeokuta, Nigeria for field performance traits. Data were collectedfrom the laboratory studies on six seed vigour traits while seven performance traits were assessed onthe field. The data were subjected to Pearson’s correlation to compute correlation coefficient (r) andstep-wise multiple regression analysis to determine percentage contribution of each trait to field emergence.The results of correlation analyses in the 2003, 2004 and across the two seasons revealed thatstandard germination, energy of germination, seedling vigour index-11, seedling vigour index-1 andspeed of germination index exhibited significant positive relationships with field emergence, seedlingestablishment, plant height, seedling dry weight and seed yield/plant. 100- seed weight significantcorrelation with plant height. From these results, all the laboratory seed vigour traits examined except100 seed weight were identified to be good predictors of field performance in NERICA rice. Regressionanalysis ranked speed of germination index as the major contributor to field emergence, accountingfor 58% of the total variation. Also, seedling establishment, standard germination and field emergencewere identified as the major contributors to seed yield/plant, accounting for 79, 77 and 66% ofthe total variation in seed yield/plant. Hence, prediction of field emergence and seed yield of NERICArice genotypes from seed vigour traits in the laboratory is possible and was effective

Challenges and Possible Panacea to the Municipal Solid Wastes Management in Nigeria

This paper provides overview of the state of municipal solid waste management (MSWM) by local authorities in Nigeria. Different areas through which the challenges can be tackled in order to improve municipal solid waste (MSW) services are discussed. With increasing global change pressures (population explosion, haphazard rapid urbanization, climate change etc.), coupled with existing un-sustainability factors, cities in developing countries are most likely to experience difficulties in efficiently managing MSW. The unplanned urbanization growth will definitely lead to huge problems on governments especially for meeting the increasing demand for proper and healthy municipal services. The growth results in increasing quantity and complexity of the generated wastes and overburdens. The rural economy needs to be improved if rural"“urban migration is to be managed. Communal efforts of local, state and federal government, the stakeholders, Non-Governmental Organizations and the private sector are paramount to attaining high level of development and sustainable MSWM

Elucidation of Phytochemicals in Mitracarpus Vilosus Flower Extract using GC-MS

Mitracarpus villosus which belongs to the family of Rubiaceae is one of the important medicinal plants widely known for its broad spectrum of pharmacological activities and biological uses which includes antioxidant, antimicrobial, anti-inflammatory, anti-cancer, anti-ulcer, and antibacterial activities amongst others. It is used in the treatment of various ailments such as ulcers, and skin-related infections like dermatitis, eczema, psoriasis, and acne. This study elucidated the phytochemical properties of Mitracarpus villosus flower. This was achieved through the methanolic extraction of M. villosus flower, and further phytochemical analysis of the methanol extract such as the tannins, saponins, flavonoids, steroids, terpenoids, and cardiac glucoside contents. Moreso, the use of Gas Chromatography-Mass Spectrophotometry (GC-MS) technique was employed on the methanolic extract to isolate and characterize the different bioactive compounds present and to further validate the qualitative data obtained from the phytochemical analysis. Results obtained exhibited the presence of tannins, saponins, flavonoids, steroids, and cardiac glucoside, with a noticeable absence of terpenoids. Also, the GC-MS analysis showed spectra of 52 bioactive compounds present in the extract with five specific compounds having the highest composition such as oleic acid (14.76%), 9,12-Octadecadienoic acid (11.25%), n-Hexadecanoic acid (10.92%), octadecanoic acid (9.21%), and squalene (8.87%) having the highest composition. The presence of these phytochemicals with their numerous biological activities in the methanolic extract of M. vilosus flower makes it a promising pharmaco-therapeutic agent, and thus should be employed in medicine for the treatment of diseases and also as an active agent in the pharmaceutical and non-pharmaceutical industries. Keywords: Mitracarpus vilosus flower, Phytochemicals, Methanol extracts, GC-MS DOI: 10.7176/JBAH/12-14-05 Publication date:July 31st 202