Production and characterization of activated carbon from leather waste, sawdust, and lignite

Powdered activated carbon (PAC) was prepared from leather buffing waste, sawdust and lignite by carbonization at temperatures between 500 – 800oC followed by steam activation. Experimental results reveal a general decrease in yield of carbon residue with increase in temperature of carbonization. Samples of lignite recorded the highest yield (49.80 – 67.70%) followed by leather buffing dust (30.70 – 39.70%) and sawdust (25.10 – 37.20%). Activated carbon from these precursors, were also evaluated for percentage ash, fixed carbon, pH and bulk density. Adsorption studies carried out with methylene blue indicate that low temperature carbonization of precursors such as leather buffing waste favour production of carbon with better adsorption efficiency while high temperature carbonization produced carbon with better efficiency from sawdust and lignite. Activated carbon from sawdust and leather buffing waste show result which compare favourably with the reference carbon used. These carbons are recommended for use in the adsorption of dyes or decolourization of organic compounds and other substances in aqueous solutions.Key words: Activated carbon, carbonization, Steam activation, Adsorption efficiency, Leather buffing wast

RETRAINING NEEDS OF MOTOR VEHICLE MECHANIC TEACHERS AND INSTRUCTORS ON AUTOMATIC TRANSMISSION SYSTEM FOR TEACHING IN TECHNICAL COLLEGES IN BAUCHI STATE

The study was designed to identify the areas of retraining needed by the teachers and instructors of Motor Vehicle Mechanics (MVM) trade in the technical colleges in Bauchi State, Northeastern Nigeria. The objective of the research was to identify the pedagogical and practical skills at technical college level. The research questions were; What are the pedagogical skills needed by MVM teachers and instructors for teaching ATS at technical college level? and What are the practical skills needed by MVM teachers and instructors for teaching ATS at technical college level? were used to guide in the conduct of the study. The null hypothesis was tested at 0.05 level of significance. A 58 item questionnaire which was face validated by three experts from the Department of Vocational and Technology Education, Abubakar Tafawa Balewa University, Bauchi State Nigeria and pilot-tested on twelve respondents from Government Technical College, Gombe, Gombe State that were not part of the study which yielded a Cronbach alpha coefficient of 0.993 was used to determine the internal consistency was used to collect data for the study. The data was analyzed using mean and standard deviation. The data support the conclusion that teachers do not feel confidence of their pedagogical and practical skills. As a result of the above revelation, the following implications arise. Teachers of MVM program in the technical colleges needed training and retraining in pedagogical as well as practical skills to enable them to perform their professional responsibilities in their practice. The pre-service training received by the teachers was found to be rickety and completely defective, which might not perfectly prepare them for effective job performance. The MVM teachers need to be retrained in order to update their knowledge, skills and competencies with respect to pedagogical and practical skills to enable be able to teach the learners efficiently and effectively, so that the learners can graduate as competent craftsmen, technicians and technologist. &nbsp

Biosorption of zinc from aqueous solution by Penicillium sp immobilised in Calcium alginate

The biosorption of Zn (II) in aqueous solution by alginate- immobilised Penicillium sp was investigated. Parameters which are responsible for optimizing sorption such as: initial pH of the solution, contact time and initial Zn (II) concentrations were varied and observed. The results were fitted into Langmuir, Freundlich and Temkin Isotherms. Optimization parameters were focused on initial solution pH, contact time and initial Zn (II) concentrations. Results were fitted to Langmuir, Freundlich and Temkin isotherms. The maximum Zn (II) biosorption of 94.29 % in aqueous solution was achieved at pH of 6.0, contact time of 120 minutes and initial Zn (II) concentration of 1 mg/L. The experimental results showed the R2 values for the isotherms to be 0.7591, 0.7780 and 0.9552 respectively for the Langmuir, Freundlich and Temkin isotherms indicating that the results fitted the Temkin isotherm more than the other isotherms. The maximum biosorption capacity was 3.78 mgg-1 while the value of n, a measure of biosorption intensity, was 1.43 Lmg-1 showing a favorable adsorption. These results show that immobilized Penicillium sp is a good biosorbent for the removal of Zn (II) from waste water with minimal environmental impact

AIRBODS: Findings and guidance for airborne infection resilience, A publication of Airborne Infection Reduction through Building Operation and Design for SARS-CoV-2 (AIRBODS)

This guidance provides insights into airborne infection risks and proposes mitigation measures to improve airborne infection resilience of indoor and semi-outdoor spaces. In some poorly-ventilated and/or highly occupied spaces, the provision of increased ventilation performance can be the key to reducing airborne infection risk down to 'acceptable' (although currently undefined)levels. This is a complex area of study with many areas of uncertainty that form the basis of ongoing research. That said, the AIRBODS programme, in the context of the global research efforts associated with the COVID-19 pandemic, has generated a sound basis for improving airborne infection resilience. Key aspects of the guide with its many recommendations include: • Experiments carried out in a test chamber showing how screens can improve or, even, worsen airborne infection risk. • Field studies undertaken as part of the Events Research Programmewhichunderpinned the opening up of the UK hospitality sector in the summer of 2021. Good practice advice is provided on how to drive high-resolution CO2 and microbiological studies and then appropriately interpret results. • Analyticalmodelswere developed to understand how infection risk, using a mass balance approach with many different parameters, might be mitigated in some circumstances when compared to reference spaces. These models were then developed into a 'full building' tool which can be downloaded as part of this guidance. • Computational fluid dynamics (CFD) models were developed to provide insights into the physics of droplets or aerosols at microscale. Following completion of a test chamber validation exercise, models were developed to investigate breathing or coughing mannequins at single human moving towards audience or crowd scale. Local ventilation effectiveness and associated airborne infection risk aspects of some real spaces may significantly differ from assumed 'fully-mixed' equivalent spaces. This, along with a number of other issues, will form part of ongoing research activities. • Focus groups were also used to provide some wider context and support some of our recommendations. AIRBODS has produced a repository of data and modelling methods with the mindset of enabling building professionals to inform their design and operation decisions towards improving airborne infection resilience in their buildings

The effect of “Gadagi” tea on liver function and serum glucose concentration in albino rats

Effect of oral administration of “Gadagi” tea on liver function and serum glucose concentration was assessed on thirty (30) healthy non – pregnant female albino rats. The animals were grouped and administered different doses (mg/kg) i.e. (low dose; 0.75mg/kg for “Sak,” 1.40mg/kg for “Sada” and 2.10mg/kg for “magani.” Standard dose; 1.50mg/kg for “Sak,” 2.80mg/kg for “Sada” and 4.20mg/kg for “magani.” High dose; 3.00mg/kg for “Sak,” 5.60mg/kg for “Sada” and 8.30mg/kg for “magani”) for a period of one week. Animals that were not administered the tea constituted the control group. At the end of one week, the animals were sacrificed and their serum alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), bilirubin (total and direct) and glucose levels were determined. Mean serum glucose level of the control animals was significantly higher (

Levels of antinutritional factors in some wild edible fruits of Northern Nigeria

Sixteen wild fruits commonly consumed in northern Nigeria were assessed chemically for the presence of oxalate, phytate, saponin, and tannin. The highest level of oxalate was found in Zizyphus spinachristi,Zizyphus mauritiana and Balanite aegyptiaca (16.20±2.12%, 15.50±1.50% and 14.50±2.08%, respectively). Phytate was highest in Sclerocarya birrea (3.56±0.54%) and Haematostaphis barteri(3.30±0.10%). B. aegyptiaca, Detarium microcarpum and Parkia biglobosa had the highest saponin values of 16.01±0.02, 12.10±0.05 and 12.23±0.46% respectively. While tannin was highest in B.aegyptiaca (7.40±0.14%), closely followed by Hyphaena thebaica (6.39±0.5%) and Borassus aethiopum (5.90±0.13%). Though these antinutrients can interfere with nutrients utilization when in highconcentration, the values obtained for the fruits analysed were not up to the toxic levels of the antinutrients. Fruits such as Vittaleria paradoxum, Adansonia digitata, Diospyros mespiliformis Phoenixdactylifera and young shoot of Bor. aethiopum are highly recommended for consumption as they contain low amount of the antinutrients analysed

AN ALTERNATIVE APPROACH ON BIOREMEDIATION OF HEAVY METALS IN TANNERY EFFLUENTS WASTE USING STREPTOMYCES SP.

  Objective: The present study is conducted to investigate the abilities of microorganisms to degrade heavy metals in industrial tannery effluent sample.Methods: Tannery effluent sample was collected from effluent treatment plant and analyzed for physicochemical parameters. The potential microbes were isolated and identified by morphological and biochemical characterization. The sample was analyzed before and after to assess the heavy metal reducing the ability of the microorganism and the respective percentage of reduction were studied using X-ray fluorescence spectrometry.Results: The samples were initially found to be highly contaminated with chromium, nickel, and cadmium. Out of three potential isolates, the isolate Streptomyces sp. was found to exhibit a better reduction against chromium (25.7%), cadmium (14.6%), and nickel (23.1%) in 50 ppm at longer incubation period. Comparatively, the reduction abilities of all the three isolates against all the three heavy metals increased with the increase in the incubation period but decreased with the increase in initial metal ion concentration except in the case of Streptomyces sp. against nickel where the reducing ability increased with the increase in metal concentration.Conclusion: Apparently, the present study revealed that Streptomyces sp. had a better remediation potential than the indigenous Pseudomonas sp. and Aspergillus sp. Ultimately, the finding of this research has shown that the Streptomyces sp. can be used as a potent bioremediation agent for treating tannery and industrial effluent in an eco-friendly process

Antibacterial activity of Euphorbia hirta against Streptococcus pneumoniae, Klebsiella pneumoniae and Proteus vulgaris

This investigation was conducted to determine the in-vitro effect of  aqueous, ethanol and methanol crude extracts of Euphorbia hirta at concentrations ranging from 10mg/ml – 100mg/ml against three pathogenic bacteria (Streptococcus pneumoniae, Klebsiella pneumoniae and Proteus vulgaris) using cup plate method. The extracts showed  appreciable inhibitory effect (6-11mm and 2-20mm) on Streptococcus  pneumoniae and Proteus vulgaris when compared to the positive control (penicillin). Klebsiella pneumoniae was resistant to all the extracts. The minimum inhibitory concentration (MIC) was between 60mg/ml – 80mg/ml on Streptococcus pneumoniae and 60mg/ml-100mg/ml on Proteus vulgaris. The minimum bactericidal concentration (MBC) was between 90-100mg/ml on Streptococcus pneumoniae and 100mg/ml on Proteus vulgaris. Phytochemical analysis revealed the presence of tannins,  flavonoids, cardiac glycosides and volatile oils. The result from this  preliminary study suggests that the plant contains active compounds that could be used for the development of drug for the treatment of ailments associated with the test organisms. More work needs to be done on the separation and purification of active compounds in the plant extract in order to determine the role of each compound in the crude extracts. Keywords: Antibacterial activity, Euphorbia hirta, Crude extracts, Bacterial isolates

Modelling the Permeation Properties of Self-Compacting Concrete Incorporating Sporocarcina Pasteuri

The face of concreting has been revolutionized with the development of self-compacting concrete, the introduction of Microbial Induced Calcite Precipitation (MICP) in concrete as well as the use of secondary cementitious materials in concrete, as it helps to improve the pore characterization of the concrete by the filling of the pore spaces and hence enhance its porosity and durability. The use of these revolutionary concrete however requires the optimization of the constituents and/or additives to concrete in order to maximize the properties thereof. There is thus a need to arrive at optimal materials quantities that can maximize the porosity characterization of the concrete without recourse to many trial and error experimentations that are both time and resources consuming. The application of modelling tools in concrete technology aids in the optimization of concrete constituents for optimal self-compacting concrete performance. In this research linear optimization models for predicting the water absorption and sorptivity of the Bio- self-compacting concrete incorporating sporosarina Pasteurii at different bacterial cell density and nutrient content with respect to age of concrete were developed for these concrete properties at 7 and 28 days with the bacterial concentration and calcium calcite content as the independent variables and water absorption and sorptivity as dependent variables; and the developed models validated using experimental data in DataFit Software. Results obtained showed that the developed linear models which took the quadratic form y(x)=a_1+a_2 x+a_3 x^2+⋯+a_n x^(n-1) were adequate for the prediction and optimization of the water absorption and sorptivity of the bio- self-compacting concrete.JCEM

Exotic Baryons in Hot Neutron Stars

We study the nuclear isentropic equation of state for a stellar matter composed of nucleons, hyperons, and $\Delta$-resonances. We investigate different snapshots of the evolution of a neutron star, from its birth as a lepton-rich protoneutron star in the aftermath of a supernova explosion to a lepton-poor regime when the star starts cooling to a catalyzed configuration. We use a relativistic model within the mean-field approximation to describe the hot stellar matter and adopt density-dependent couplings adjusted by the DDME2 parameterization. We use baryon-meson couplings for the spin-$1/2$ baryonic octet and spin-$3/2$ decuplet determined in a unified manner relying on $\text{SU}(6)$ and $\text{SU}(3)$ symmetry arguments. We observe that $\Lambda$ is the dominant exotic particle in the star at different entropies for both neutrino-free and neutrino-trapped stellar matter. For a fixed entropy, the inclusion of new particles (hyperons and/or delta resonances) in the stellar matter decreases the temperature. Also, an increase in entropy per baryon ($1\;\text{to}\; 2$) with decreasing lepton number density ($0.4\;\text{to}\; 0.2$) leads to an increase in stellar radii and a decrease in its mass due to neutrino diffusion. In the neutrino transparent matter, the radii decrease from entropy per baryon $2$ to $T\,=\,0$ without a significant change in stellar mass.Comment: 9 pages, 10 figure