Determination of physiological maturity in corn

Ten corn hybrids differing in maturity were planted in the summer of 1978 in order to predict and determine the time of physiological maturity and the rate of moisture loss following maturity. The design of the experiment was a randomized complete block. Observation and measurements of maturity factors included leaf number per plant, dates of tasseling and silking, dates of dead leaf and brown husk formation, dates of kernel denting and of black layer formation, percent moisture of grain and cobs, and the yield of grain. Leaf number varied from 15 to 19, while tasseling and silking occurred from 55 to 66 and 61 to 69 days after planting. There was a positive correlation between the number of leaves and the number of days from planting to silking. Kernel denting occurred in 109 to 116 days after planting and 40 to 51 days after silking. Black layer formation ranged from 57 to 64 days after silking, and the moisture level at this stage varied from 21.8 to 33.3% in grain and 26.8 to 54.6% in cobs. Correlation of leaf number and number of days to silking to number of days to black layer after silking was low. However, moisture percentage was negatively correlated to number of days to black layer formation. The rate of drying (percent moisture loss) was found to be faster in cobs than in the grain but equilibrium was reached in the two at about 19 to 23% among the hybrids. Yields generally varied inversely according to the length of the physiological periods. Based on the data from maturity factors enunciated earlier on, Princeton SX910, Pioneer brand 3184, Funk G-4507, DeKalb XL72B, Funk G-4525, DeKalb XL80 and FFR707C were classified as early maturing, while Pioneer brand 3147, Funk G-4848 and DeKalb XL394 were late maturing. No single factor measured proved to be an accurate prediction of the date of physiological maturity as indicated by black layer formation. The moisture content of various hybrids at maturity varied by as much as 11% among hybrids

Effect of genotypes on soyabean seed quality development under West African Rainfed conditions

Effect of genotypes on soyabean seed quality development was monitored under rainfed conditions at Abeokuta between July and November, 1997. A consistent increase in rate of normal germination and seedling emergence occurred among early harvests. Greatest germination rate was detected in seeds harvested around physiological (functional) and harvest (full) maturity stages. Seedling emergence was significantly influenced by seed harvest date in all soyabean entries. Germination and emergence increased as soyaben seed development progressed and was greatest for seeds harvested between R7 and R8 in all soyabean cultivars. Enforced desiccation to 10% moisture content promoted germination of seeds harvested around physiological maturity stages. The onset of desiccation tolerance fell between physiological and harvest maturity stages in all the six soyabean cultivars. The rapid decline in seedling emergence of artifically dried seeds at 50d after mtff as against 60d after mtff for normal laboratory gemination indicated that seedlots of initial good germination may not necessarily produce high seedling emergence under good seeding condition due to differences in genotypes. Association of seed characters such as seed size, seed weight, germinability and emergence ability is essential in soyabean breeding to facilitate selection of genotypes with good seed quality, thereby reducing elaborate storage and screening methods

DISTRIBUTION AND BIOAVAILABILITY OF METALS IN GASOLINE CONTAMINATED SITES IN LAGOS, NIGERIA

Distribution of metals in soil of two gasoline contaminated sites in Lagos were studied. Total Concentrations of twenty-five elements were investigated in composite samples collected at different depths within the sites. The elements were determined by ICP-AES after microwave assisted acid digestion of the samples. Chemical fractionation, mobility and potential bioavailability of some of the toxic and EU priority metals e.g., Pb, Cu, Cd, and Fe were evaluated in the topsoil (0-15 cm) by sequential extraction. There were great variation in the concentrations of the elements in both sites with depth. Speciation analysis showed that Pb and Cd dominated the Fe-Mn oxide fraction while the concentrations of Fe and Cu were higher in the residual fraction in site A. In site B, Pb, Cu and Cd was mainly associated with the Fe-Mn oxide fraction, while Fe was in the residual fraction. Cd has the highest mobility factors, 33.2% (site A) and 29.5% (site B), respectively. The concentrations of most of the toxic heavy metals (e.g., Pb, Zn, Cu, Cr, Cd etc.) exceed that of the control samples and heavy metal baseline values around the world. Thus, proper management of these potentially contaminated sites is imperative to prevent human health risk

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

Performance of Wild Fruit Marketing in Nigeria: A Case Study of African Star Apple (Chrysophllum Albidum) in Ilorin Metropolis, Kwara State, Nigeria

This study examined marketing of wild fruits in Nigeria using African Star Apple as a case study. The study stemmed from the need to satisfy the nutritional requirements of the populace through efficient marketing of wild fruits. Specifically, the study examined the socio-economic characteristics of African Star Apple marketers in the study area, determined the marketing margins among the intermediaries involved in marketing of the crop, and identified the factors militating against efficient marketing of the commodity in the study area. Descriptive statistics, marketing margin and marketing efficiency analyses were the analytical tools adopted for the study. The findings revealed that marketing of African Star Apple was profitable and efficient in the study area. Majority of the intermediaries were not members of any cooperative society. The study also reveals inadequate credit facilities, seasonal variation in price, high transportation cost and poor storage system as the major problem facing marketing of the commodity in the study area. This is unfavourable to producers, marketers as well as consumers and the economy as a whole. The study therefore calls for formation of cooperative societies by marketers of wild fruits, provision of good roads, development of efficient storage system, credit facilities and market stalls.Key words: nutritional requirements, wild fruits, intermediaries, efficientt marketin

Energy efficient lighter weight aluminium matrix composite automotive brake motor

With 75 percent of fuel consumption relating directly to vehicle weight, potential weight reductions that can result in improved performance ratio and reduce CO2 emissions stimulate the application of lightweight materials. The substitution of aluminium matrix composite (AMC) for structural component of brake rotor is quite effective in lightening, energy efficiency and hence mitigation of global warming. Mathematical models are used to evaluate the influence of light weight material on energy and the environment. This study attempts to predict the effect of weight reduction on energy consumption and CO2 emissions by replacing conventional materials for light weight AMC. The study found that a weight savings of 50 to 60% from the AMC brake rotor can translate to an energy savings of 16-18% in energy usage and hence reduction in CO2 emission in the environment. This study will facilitate a cleaner and healthier environment for human life in the society

Preparation and characterisation of TIG-alloyed hybrid composite coatings for high-temperature tribological applications

There is an increasing interest in the tribology community for developing high-performance composite coatings to meet severe tribological conditions in advanced mechanical systems which require high operating temperature and long life. In the present work, powder preplacement and tungsten inert gas (TIG) torch melting techniques have been employed to generate titanium carbide (TiC)-based composite coatings containing hexagonal boron nitride (hBN) or Ni–P coated hBN (Ni–P-hBN) lubricant additive. The effects of preplaced powder composition on the cross-sectional microstructures and surface hardnesses of the developed coatings were analysed. Furthermore, the friction and wear behaviours of the composite coatings at 600°C were evaluated using a Ducom ball-on-disc wear test rig. The results indicate that the TIG-melted surface containing TiC and Ni–P-hBN powder mixtures exhibits optimum properties combining good control of microstructures and uniformly distributed hardness as well as excellent tribological properties due to the enhanced wettability action of Ni–P encapsulated hBN particles

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

Gender Differentia Among Fish Farmers Within Ilorin Metropolis, Kwara State, Nigeria

Gender differentia among fish farmers within the Ilorin metropolis, Kwara State, Nigeria was studied with the aim of evaluating the level of involvement of the different gender in fish production activities, accessing their access to credit, and the constraints faced by them. A multistage sampling technique using a structured questionnaire was adopted for this study, the sample size was 210 using a structured questionnaire. Data were analyzed using SPSS 16.0. 61.90% of respondents were male while 52.5% and 49.2% of female and male respondents respectively were in their active age group of < 30 years. Females were more involved in fish marketing (42.90%) and fish processing (48.75%). There exist a significant association (p<0.05) between gender and level of involvement in fish marketing (χ2=9.20, p<0.05), access to land (χ2=10.69, p<0.05), and fish production activities (χ2=11.83, p<0.05). Access to credit was poor. Constraints faced include poor access to credit facilities, inadequate information, high cost of feed production, and poor water quality. It is therefore recommended that access to credit facilities banks of agriculture, microfinance banks, and commercial banks should be improved on while fish farmers are also encouraged to form cooperative societies as it will improve the capacity building of farmers and ease their credit acquisition for farming activities