Metal complexes as potential ligands : the deprotonation of aminephenolate metal complexes

The cationic nickel, copper and zinc complexes of tris-(2-hydroxybenzyl)-aminoethylamine (H6TrenSal) have been deprotonated using potassium hydroxide. The nickel complex can be sequentially deprotonated to form a series of compounds namely, [(H6TrenSal)Ni]+, [(H6TrenSal)Ni] and "[(H6TrenSal)Ni]K". The latter is isolated as a mixture of species namely [{(H6TrenSal)Ni}K(EtOH)]2, [{(H6TrenSal)Ni}K(EtOH)2-μ-OH2]2 and [{(H6TrenSal)Ni}K(EtOH)2-μ-EtOH]2, which co-crystallise in a roughly 50:27.5:22.5 ratio. In contrast the deprotonation of [(H6TrenSal)M]+ (M = Cu, Zn) results in the formation of tetrameric complexes [({(H6TrenSal)Ni}K(OH2)2)4(μ4-OH2)]

External debt, debt overhang, crowding out effects and capital formation in Nigeria and South Africa

The deficiency of saving in Sub-Saharan Africa, as represented by Nigeria and South Africa has led to shortages in funding capital formation, thereby necessitating external borrowing. This has slowed down and restrained economic growth and development. The questions of external debts determinants, effects and causal relationships with capital formation are yet to be adequately responded to; mainly due to weak and nonrigorous methods employed in the previous studies. The focus has not been effective and specific. The objective of this study is fourfold; determine factors affecting external debt accumulation, examine effects of external debt on capital formation, assess impact of debt overhang and crowding out effects on capital formation and investigate causal relationships between external debt and capital formation in Nigeria and South Africa. Autoregressive distributive lag (ARDL) and Vector Autoregressive (VAR) modeling on time series data covering three decades were employed in the study. The results have established that, interest rate and external debt service are the most statistically significant variables explaining external debt accumulation scourge in the selected countries. Additionally, the study has discovered that, external debt has significant negative effects on capital formation in the same manner with debt overhang and crowding out effects. However, these impacts are proven to be more pronounced on capital formation in Nigeria than in South Africa. It is also established that external debt and capital formation Granger causes each other. The overall implication of the research findings is that speed of capital formation has been retarded by the negative effects of external debts. Measures by the government should be tailored towards improving capital formation by designing policies that will reduce the burden of debt accumulation and reducing the cost of external debt services. This can be done through enhancing the debt management process and improving efficiency in funds utilization, so as to ensure timely repayment and servicing of debts

Silver (I) complexes of methylene bridged quinoline functionalised Heterocyclic Carbene Ligands

This paper describes the synthesis of Silver (I) complexes of methylene bridged quinoline functionalized Heterocyclic Carbene Ligands, by stirring imidazolium salts with silver oxide to obtain the complexes in good yield. The complexes were structurally characterized by 1H NMR, 13 NMR, microanalysis and X-ray crystallography. The geometry of the complexes as revealed by the crystal structure showed that the complexes have linear structures. All reactions involving silver were conducted under the exclusion of light. Keywords: NHC, Imidazolium salt, ligand, silve

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Abstract The outbreak of the coronavirus pandemic caused a sharp change in the educational practice world over as schools and institutions of learning are forced to seek alternatives to teaching styles.  Learning centers were shut down to follow the order of social distancing, as a precautionary measure against the infectious virus disease that has rampaged the world. This paper studies the professional consequences of the challenges fronting the English language teaching in Nigeria in the period of coronavirus pandemic otherwise known as “Covid-19”. It also offers how the needs and goals of the learners can be met in the period of the mandatory homestay.  The article collects, collates, and reviews the data that comes up in the Learn at Home Program (LHP) webpage which is created for the purpose of continuing education in the time of “Covid-19”. A survey of the participants' responses was also conducted to investigate the efficacy and challenges that they encountered during the online delivery through the use of a variety of media stations on different topics of secondary schools in Nigeria. The paper, after pitching the challenges of this virtual instruction at the time of the pandemic, proffers certain solutions that can boost the efficacy of virtual education generally in Nigeria.         Keywords: challenges, teaching, coronavirus, pandemic, e-learning. &nbsp

The Impacts of Oil Price and Exchange Rate on Food Prices in Nigeria

This empirical research examined the interconnecting relationship between oil price, exchange rate and food prices in Nigeria. The study applied annual time series data from 1972 to 2016. Autoregressive Distributed Lag (ARDL) techniques were used in the process of estimating the model. The main results disclosed that there is a long run association among the considered variables. The error correction term indicates significant negative sign. Among the two independent variables in the model, exchange rate is affecting food price more than the oil price counterpart since some of the food items are imported. The result has robust implication on policy recommendations in Nigeria. Food production has a vital role in influencing food prices in Nigeria. The Central Bank of Nigeria must consider exchange rate as a factor influencing food price in its quest for achieving inflation target. Keywords Oil price; exchange rate; food price; ARDL; Nigeria DOI: 10.7176/JESD/10-8-08 Publication date: April 30th 201

Synthesis and Characterization of Cobalt Homotrinuclear Biologically Active Compound

N4O3 tripodal Schiff-base ligand namely tris(5-Bromo-2-hydroxybenzylaminoethyl)amine (Tren5BrSal) have been prepared and characterized by various spectroscopic methods . It is derived from the condensation reactions of tris(2-aminoethyl)amine (Tren), with 3 equivalents of 5-bromo-2-hydroxybenzaldehyde (5BrSal). The Cobalt(III) complex of the resulting ligand was obtained from the reaction of Tren5BrSal with the salt of  cobalt in absolute methanol. The antimicrobial screening was carried out against two bacterial species (Escherichia coli and Streptococc. Sp) and two fungal species (Aspergillus niger and Fusarium sp.). The complex is found to exhibit high antibacterial and anti fungal activity. Keywords: Schiff- base, tris-(2-aminoethyl)amine, Tren5Brsal, Cobalt

Semantic Retrieval System for Nigerian Onion Domain Ontology

With the recent Nigerian Government’s effort to diversify its economy, several efforts have been put in place by the Government to revitalize Nigerian Agricultural sector as part of the diversification effort. Part of effort put in place to revitalize Agriculture it to encourage local and international investment into Agriculture in the country.  However, due to lack of enough information on the agricultural activities in the country remains a challenge in the revitalization of the country’s agriculture. Although Google and other search engines provide access to data on the Web, these search engines are base on traditional keyword search and therefore lack semantics which affect the effectiveness of the retrieved results.   This paper presents semantic document retrieval of Nigerian Onion domain. The work involves developing Ontology for Nigerian Onion domain. Protégées Ontology editor is then used to store the Ontology and OWL-DL query is used to retrieve the documents semantically.  To measure the effectiveness of the proposed work, precision and recall evaluation metrics were used. Keywords: Ontology, Onion, Information Retrieval, Semantic Retrieval, Domai

Synthesis of Mn(II) and Fe(II) Complexes with Ethylenediamine and Acetylacetonate Ligands

Synthesis of acetylacetonato, ethylenediamine manganese (II) complex and acetylacetonato, ethylenediamine iron (II) complex were carried out, a pale yellow and brown solids were obtained from the reaction.  The solubility tests of the complexes were carried out, in which manganese (II) complex was found to be soluble in water, methanol and ethanol and insoluble in chloroform and petroleum ether while the iron (II) complex was found to be slightly soluble in water, methanol and ethanol and insoluble in chloroform and petroleum ether. The UV visible spectra of manganese (II) complex showed absorption maximum at around 480nm, and infrared spectra of manganese (II) complex showed absorption band at 1725cm-1. Keywords: Acetylacetone, manganese, iron, ethylenediamine

Renewable Energy, Regulation, Employment and Environmental Sustainability in Sub-Saharan Africa

This paper examines the impact of employment, regulatory quality and urbanization on environmental quality by using renewable energy as a metric of environmental indicator in sub-Saharan Africa. The environmental Kuznets curve (EKC) theory was used as the theoretical framework while the difference Generalized Method of Moments (GMM) was utilised as the estimation technique. 45 sub-Saharan African countries covering the period of 2008 to 2016 were used as the sample size. The result reveals that increase in employment and income is at expense of environmental quality while regulation quality and urbanization increase environmental quality. As such, policymaking in the region should support the development of renewable energy by providing incentives that encourage private sector investment in renewable energy; implement sound policies and regulations that promote private sector employment and smart cities development. Keywords: Renewable energy; environment, regulation, employment, sub-Saharan Africa DOI: 10.7176/DCS/9-7-04 Publication date:July 31st 201

Ramadan tafsir of the glorious Qur’an goes virtual during Covid-19 lockdown in Nigeria

The researchers were motivated by the adoption of digital communication applications and social media platforms by some Islamic scholars in Nigeria to conduct annual Tafsir of the glorious Qur’an in Ramadan 2020 in the midst of coronavirus lockdown. The paper adopted Lull’s Gratification Theory for theoretical explanation of virtual interaction between the scholars who conducted the Tafsir from an isolated places and the audience who watched or listened from their homes in adherence to safety measures to stop the spread of the disease. Methodologically, the study adopted a cross-sectional research design and purposive sampling technique to elicit secondary data from the target participants. The study found that there is usage of digital medium of communication and interaction between Islamic clerics and their followers. This explains the flexibility of Islam to embrace development, adopt and adapt it in conformity with Islamic rules and regulations. The findings also show that Facebook, WhatsApp and Telegram are the most common internet based interactive platforms which Islamic scholars explored and disseminated their Tafsir virtual to the audience. The paper concludes that internet has enabled people not only to interact virtual but Tafsir and other forms of Islamic preaching can be conducted without co-presence of the preachers and the audience. The option of live streaming video on Facebook, WhatsApp and Telegram which consume a lot amount of data has enabled Muslim users to followed the Ramadan Tafsir from distant places