Synthesis, characterisation and antimicrobial studies on 2 - [(2 -hydroxyphenyl) methylidene] hydrazine-1-carbothioamide and its Ni(II) and Cu(II) complexes

2-[(2-hydroxyphenyl)methylidene]hydrazine-1-carbothioamide was obtained by the condensation of salicyldehyde and thiosemicarbazone. Ni(II) and Cu(II) complexes were prepared and characterized by elemental (CHNOSO) analysis, FTIR, UV – visible, magnetic susceptibility, and molar conductance measurements. The ligand sharp peak at 1616cm-1 in the FTIR spectra indicating the formation of azomethine (-C=N-) bond. A shift shows band to the band regions 1597cm-1 and 1510cm-1 confirmed the coordination of the azomethine nitrogen with Nickel(II) and Cu(II) ions respectively. The ligand formed a chelate with 1:2 metal : ligand stoichiometry. All the compounds have been screened for antibacterial and antifungal activity by disc diffusion method against Staphylococcus aureus, Escherichia coli and Salmonella typhi as well as Aspergillus flavus bacterial and fungal isolates respectively. The compounds are found to be active against the tested isolates.Keywords: Schiff base, Chacterisation, Ligand, Antibacterial, Antifunga

The Effect of Varying Soot Concentration and Relative Humidity on Visibility and Particle Size Distribution in Urban Atmosphere

This research used extracted extinction coefficients and common mode radii of urban aerosols to carry out visibility simulations at corresponding spectral wavelengths from 0.4-0.8µm from the improved version of the Optical Properties of Aerosols and Clouds (OPAC 4.0) data at eight relative humidities(RH) (0%, 50%, 70%, 80%, 90%, 95%, 98% and 99% RH). Five models of the urban aerosols used comprised of insoluble (INSO), Water-soluble (WASO) and Soot (Black Carbon). From the average concentration set up by OPAC 4.0, the concentrations of the Soot (Black Carbon) were varied by external mixing. The Angstrom exponent (α), the curvature (α2) and the urban atmospheric turbidity (β) were obtained from the regression analysis of the first and second order polynomial of Kaufman’s representation of the Koschmieder equation for atmospheric visibility. The mean exponents of the aerosol size growth curve (µ) were determined from the aerosol effective hygroscopic growth (geff) while the humidification factors (γ) were determined from the visibility enhancement factors f(RH,λ). With µ and γ, the mean exponents of aerosol size distributions (υ) were determined for all the models. It was observed that at varying Soot (Black Carbon) concentrations and RH there were non-linear relationships between them and visibilities. The values of α > 1 showed the presence of fine mode particles from the WASO part of the aerosol mixture and α2 being positive indicated bimodal aerosol particle distributions. Additionally, visibility deterioration is predicted because of the increase in turbidity (β) with the variation of Soot and RH

The role of biosensors and biological weapons in national defence and security operations

The knowledge of biotechnology plays an important role in the development of biological weapons. Biological weapons are considered an attractive factor in war for several reasons: ease of manufacture, low cost, confirmed injury, increased number of victims, large losses incurred by other countries. Biological weapons detection methods are among the most important means of military defense. Biological sensors are used in early detection of weapons. Biotechnology is of paramount importance in all fields of medicine, engineering, agriculture, industry, as well as military life. The key applications of biotechnology in the military are in the areas of sensor systems and systems for protection from espionage. Among the most important countries that have applied knowledge of bioweapons technology into their security system are the USA and China. Despite the enormous advantages of biotechnology, it has negative effects in biological weapon production. Therefore, the near future will witness a tremendous boom in biotechnology. DNA profiling also plays an important role in detection of crime. The overall aim of the review is to emphasize the importance of biotechnology towards solving bioterrorism and other forms of security challenges in an environment

Effect of Heat Treatment and Sulfuric Acid Anodization on Corrosion Resistance of Aluminum Alloy (AA7075)

This paper, studied the effect of heat treatment and anodization on corrosion resistance of aluminum alloy 7075 (AA7075), with a view to improving its corrosion resistance. Microstructure and micro hardness of the anodic film of the samples were studied with the aid of optical metallurgical microscope and automated micro hardness testing machine. Linear polarization methods were used to assess the corrosion behaviour of the alloy in 0.5M HCl. The microstructure of the annealed sample showed formation of dendrites while precipitation hardened samples in palm kernel oil and SAE 40 engine oil showed precipitates of MgZn2. The SEMS result showed pores and micro cracks on the surfaces of the anodized samples, with the as cast and anodized sample in sulfuric acid exhibiting most compact with few pores. The as cast and sulfuric acid anodized sample shows highest micro hardness value of 205.33 HV, while the least value of 150.67 HV was recorded in sample precipitation hardened in SAE 40 engine oil and anodized in sulfuric acid. Analysis of the potentiodynamic polarization data and curves showed a linear relationship (decrease in icorr, decreases the corrosion rate) between current density and the corrosion rate in all the samples. Higher polarization resistance of 15.093 Ω/cm2 was recorded by the as cast and Sulfuric acid (SA) anodized sample while the precipitation treated in SAE 40 engine oil plus SA anodized sample recorded lowest polarization resistance of 5.2311 Ω/cm2. Heat treatment alone improves corrosion resistance of AA 7075 in 0.5 M HCl solution but heat treatment plus SA anodization does not improve corrosion resistance in the same environment

Knowledge, sources of information, and risk factors for sexually transmitted infections among secondary school youth in Zaria, Northern Nigeria

Background: Sexually transmitted infections (STIs) are responsible for a variety of health problems especially among the youth who engage in risky sexual behavior. There are few studies that describe STIs among the youths in Northern Nigeria. The objective of the study was to assess knowledge of STIs and risk factors among secondary school youth. Materials and Methods: This was a cross‑sectional study in which structured, self‑administered questionnaire was used to collect data on socio‑demographics, knowledge on STIs, and risk factors. Three senior secondary schools were purposively selected for the study. Results: A total of 1765 youths aged 10‑30 years with mean age of 16.9 ± 2.0 years participated in the study. 1371 (77.7%) and 394 (22.3%) were respectively Muslim and Christian. Mean age at first sexual intercourse was 16.7 ± 2.0 years.A majority (67.6%) of them heard about STIs; sources of information of STIs were school lessons 23.6%, mass media 23.3%, and health magazines 19.2%, respectively. Generally, knowledge on STIs was good as 75.4% of respondents knew how the disease is transmitted. This knowledge was significantly associated with class of student, place of treatment, and religious teaching (χ2 = 9.6, P = 0.047, χ2 = 22.1, P = 0.035 and 42.6, P = 0.001, respectively). Mean knowledge score was 0.698 ± 0.01. A majority of respondents were engaged in risky sexual behavior as only 16.2% use condom as a preventive measure. Eleven percent reported ever having an STI in the past and majority (52.8%) go to government hospital for treatment of acquired STI. 56% of the youth had two or more boy/girl friends and 30% had sexual relationships. Conclusion: It was concluded that secondary school youth had good knowledge about STIs; however, the opposite is true when it comes to preventive practice (use of condom). Interventions such as periodic publicity awareness and school seminars focusing on STI preventions are needed to control the disease among the youth

Modelling hatchability and mortality in muscovy ducks using automatic linear modelling and artificial neural network

This study was embarked upon to predict hatchability and mortality rate of Muscovy ducks in Nasarawa State, Nigeria. Data were obtained from a total of 119 duck farmers. The automatic linear modelling (ALM) and artificial neural network (ANN) models were employed. The average flock size was 9.84±0.60 per household. The predicted hatchability mean values using ALM (8.66) and ANN (8.65) were similar to the observed value (8.66). The predicted mortality mean values using ALM (2.95) and ANN (3.03) were also similar to the observed value of 2.95. Experience in duck rearing, the educational status of farmers, source of foundation stock and season were the variables of importance in the prediction of hatchability using ALM and ANN models. However, primary occupation, source of foundation stock, experience in duck rearing, land holding and management system were the important variables automatically selected for the prediction of mortality. Moderate coefficients of determination (R2 = 0.422 vs 0.376) and adjusted R2 (0.417 vs 0.371) estimates were obtained for hatchability and mortality using ALM. Different patterns were obtained under the ANN models as regards the prediction of hatchability (R2= 0.573 and adjusted R2= 0.569) and mortality (R2= 0.615 and adjusted R2= 0.612). The present information may aid management decisions towards better hatchability and mortality performance in Muscovy ducks

Simulation of Hydrodesulphurization (HDS) Unit of Kaduna Refining and Petrochemical Company Limited

This research was carried out to simulate the Hydrodesulphurization unit using ASPEN HYSYS with the aim of removing impurities such as Sulphur, Nitrogen and Oxygen in raw Kerosene. The simulation is based on conditions and parameters (mass flow rates, temperature and pressure readings) obtained from the Linear Alkyl Benzene (LAB) plant of the Kaduna Refining and Petrochemical Company (KRPC). After the successful completion of the simulation, total removal of impurities was achieved as the concentration of sulphur, nitrogen and oxygen in mole fraction present in the treated Kerosene stream was approximately zero. The treated Kerosene composition indicated 0.0021, 0.3342, 0.3322 and 0.3315 mole fractions of n-C13, n-C14, n-C15 and n-C16 respectively. Key words: Simulation, Hydrodesulphurization, Aspen Hysys, Impurities

Yield and Yield Attributes of Extra-early Maize (Zea Mays L.) as Affected by Rates of Npk Fertilizer Succeeding Chilli Pepper (Capsicum Frutescens) Supplied with Different Rates Sheep Manure

Field experiment was conducted in 2005 and 2006 to study response of extra-early maize variety (95TZEE-Y1) to rates of NPK (0, 40:20:20, 80:40:40 and 120:60:60 kg N:P2O5:K2O ha-1) and residual FYM (0, 5, 10 and 15 t ha-1 applied to chilli pepper the previous season) in the semi-arid zone of Nigeria. Randomized complete block design with three replicates was used. Higher values for soil physical and chemical properties were obtained in plots supplied with manure the previous season with soil from 2006 experiment more fertile than for the first year, hence produced 21% more grain yield. All the applied NPK rates in 2005 and except 40:20:20 ha1 in 2006 had resulted in early maize crop as compared to control. Husked and de-husked cob and 100-grain weights and grain yield/ha were higher at 120:60:60 kg NPK ha-1. Maize grown in plot supplied with 15 t FYM ha1 the previous year matured earlier. Cobs and 100-grain weights and grain yield were highest in plot supplied with 10 t FYM ha1. The 10t FYM ha-1 had 69% and 68% more grain yield than the control in 2005 and 2006, respectively. Highest maize yield was obtained at 120:60:60 kg NPK ha-1 or 10t FYM ha-1. All the parameters measured significantly and positively related to each other when the two years data were combined

The mechanical performance of sugar palm fibres (Ijuk) reinforced phenolic composites

Sugar palm fibres are one of the natural fibres which have many features and need further study to understand their properties. The aim of this work is to investigate the flexural, compressive and impact properties of sugar palm fibres reinforced phenolic composites. Sugar palm fibres were used as a filler (particle size 150 μm) and with loading of 0, 10, 20, 30, and 40 vol.%. The fibres were treated by sea water and then fabricated into composites by hot press technique. Flexural, compressive, and impact tests were carried out as per ASTM D790, ASTM D695-08a, and ASTM D256 standards, respectively. Scanning electron microscopy (SEM) was used to investigate the morphology and the interfacial bonding of the fibres-matrix in composites. The results show that the mechanical properties of the composites improve with the incorporation of fibres. The composite of 30 vol.% particle loading exhibit optimum values which are 32.23 MPa, 61.66 MPa, and 4.12 kJ/m2 for flexural, compressive, and impact strength, respectively. This was because good compatibility of fibre-matrix bonding. Consequently, sugar palm fibre is one of the prospective fibres and could be used as a potential resource to reinforcement polymer composite

Mechanical, thermal, tribological, and flammability properties of polybutylene terephthalate composites: Comparing the effects of synthetic wollastonite nanofibers, natural wollastonite, and graphene oxide

Abstract Polybutylene terephthalate (PBT) composites were prepared with 1.0 phr synthetic :wollastonite nanofibers (SWN), natural wollastonite (NW) and graphene :oxide (GO) to study the effect of different fillers on mechanical, thermal, tribological,and flammability properties. The properties of PBT composites arerelated to the size, structure, and interfacial adhesion of the fillers in PBT matrix. PBT/SWN demonstrated the highest tensile strength and Young's modulus (6% and 9% increment), followed by PBT/NW (1.3% and 7% increment) and PBT/GO (2% decrement and 4% increment). PBT/SWN gave the highest degradation temperature (409�C), followed by PBT/GO (404.7�C). The maximum enhancement in wear resistance (73%) by PBT/SWN and anti-friction performance (26%) by PBT/GO evinced the excellent load-bearing ability of SWN and the great lubricating effect of GO. PBT/NW had the lowest peak heat release rate, smoke, and carbon dioxide production rate. This study shows that :PBT composites have great potential in different automotive applications. :KEYWORDS :flame retardance, friction and wear, mechanical properties, polymer-matrix composites,thermal properties Received: 24 August 2022 Revised: 28 October 2022 Accepted: 15 November 2022 DOI: 10.1002/app.53463 J Appl Polym Sci. 2022;e53463. wileyonlinelibrary.com/journal/app © 2022 Wiley Periodicals LLC. 1 of 1