Search results for: Alhassan Dramani Yakubu

Authors: Aminu Yakubu Umar

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X-ray is the major contributor to the effective dose of both the patient and the personnel. Because of the radiological risks involved, it is usually recommended that dose to patient from X-ray be kept as low as reasonably achievable (ALARA) with adequate image quality. The implementation of quality assurance in diagnostic radiology can help greatly in achieving that, as it is a technique designed to reduce X-ray doses to patients undergoing radiological examination. In this study, quality control was carried out in six hospitals, which involved KVp test, evaluation of total filtration, test for constancy of radiation output, and check for mA linearity. Equipment used include KVp meter, Rad-check meter, aluminum sheets (0.1–1.0 mm) etc. The results of this study indicate that, the age of the X-ray machines in the hospitals ranges from 3-13 years, GHI and GH2 being the oldest and FMC being the newest. In the evaluation of total filtration, the HVL of the X-ray machines in the hospitals varied, ranging from 2.3-5.2 mm. The HVL was found to be highest in AHC (5.2 mm), while it was lowest in GH3 (2.3 mm). All HVL measurements were done at 80 KVp. The variation in voltage accuracy in the hospitals ranges from 0.3%-127.5%. It was only in GH1 that the % variation was below the allowed limit. The test for constancy of radiation output showed that, the coefficient of variation ranges from 0.005–0.550. In GH3, FMC and AHC, the coefficient of linearity were less than the allowed limit, while in GH1, GH2 and GH4 the coefficient of linearity had exceeded the allowed limit. As regard to mA linearity, FMC and AHC had their coefficients of linearity as 0.12 and 0.10 respectively, which were within the accepted limit, while GH1, GH3 and GH4 had their coefficients as 0.16, 0.69 and 0.98 respectively, which exceeded the allowed limit.

Keywords: radiation, X-ray output, quality control, half-value layer, mA linearity, KVp variation

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Authors: Oladipo Joseph Ajayi, Yakubu Muhammed, Caleb Galadima

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This study was conducted to examine the income diversification of smallholder farmers in Bosso Local Government area of Niger state, Nigeria. The specific objectives were to examine the socio-economic characteristics of the farmers, identify the sources of income among the farmers, determine the pattern of income diversification and evaluate the determinants of income diversification of farmers in the study area. A multi-stage sampling technique was used to select 94 respondents for the study. Primary data were used, and these were collected with aid of a well structured interview schedule. Descriptive statistics, diversity index, and Tobit regression model were employed to analyze the data. The mean age of the farmers was 44 years. The average household size was 8 members per household, and the average farming experience was 12 years. 21.27 percent did not have formal education. It was further found that 69.1 percent of the respondents had an income diversity index of 0.3-0.4. This indicated that their level of income diversification was moderately low. The determinants of income diversification in the study area were education, household size, marital status, and primary income. These variables were positively related to income diversification. The study revealed that diversification into various income sources has helped to increase household income to sustain the family demands even though their level of income diversification was low within the study area.

Keywords: diversification, income, households, smallholder farmers

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Authors: O. J. Sharaibi, O. T. Ogundipe, O. A. Magbagbeola, M. I. Kazeem, A. J. Afolayan, M. T. Yakubu

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Hyperprolactinemia is a condition of elevated levels of serum prolactin in humans. It is one of the major causes of female infertility because, excess prolactin inhibits gonadotropin secretion. When gonadotropin is low, follicle stimulating hormone (FSH) and luteinizing hormone (LH) secretions are low and so, do not stimulate gamete production and gonadal steroid synthesis. The aim of this study is to identify and investigate indigenous medicinal plants that can be used in the treatment of hyperprolactinemia. Based on the frequency of mentioning during the ethnobotanical survey, Nymphaea lotus L. was selected for studies. The prolactin-lowering potential of aqueous extract of N. lotus and its effects on other female reproductive hormones in comparison with bromocritptine was evaluated by inducing hyperprolactinemia with metoclopramide at a dose of 5 mg/kg body weight of the animals for 21 days and then administered various doses of aqueous extract of N. lotus for another 21 days. Aqueous extract of N. lotus at 50, 100 and 200 mg/kg body weight significantly reduced the serum prolactin levels in female Wistar rats by 40.06, 52.60 and 61.92 % respectively. The extract at 200 mg/kg body weight had higher prolactin-lowering effect (61.92%) than bromocriptine (53.53%). Aqueous extract of N. lotus significantly increased (p < 0.05) the serum concentrations of FSH, LH and progesterone while estradiol concentrations were reduced. This study shows that Nymphaea lotus is a medicinal plant that can be used in the treatment of hyperprolactinemia.

Keywords: hyperprolactinemia, infertility, metoclopramide, Nymphaea lotus

Procedia PDF Downloads 259

Authors: M. Al Huwayz, A. Salhi, S. Alhassan, S. Alotaibi, A. Almalki, M.Almunyif, A. Alhassni, M. Henini

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Recently, there has been much research carried out to investigate quantum dots (QDs) lasers with the aim to increase the gain of quantum well lasers. However, one of the difficulties with these structures is that electrically active defects can lead to serious issues in the performance of these devices. It is therefore essential to fully understand the types of defects introduced during the growth and/or the fabrication process. In this study, the effects of Gamma radiation on the electrically active defects in p-i-n InAs/InGaAsQDs laser structures grown by Molecular Beam Epitaxy (MBE) technique on GaAs substrates were investigated. Deep Level Transient Spectroscopy (DLTS), current-voltage (I-V), and capacitance-voltage (C-V) measurements were performed to explore these effects on the electrical properties of these QDs lasers. I-V measurements showed that as-grown sample had better electrical properties than the irradiated sample. However, DLTS and Laplace DLTS measurements at different reverse biases revealed that the defects in the-region of the p-i-n structures were decreased in the irradiated sample. In both samples, a trap with an activation energy of ~ 0.21 eV was assigned to the well-known defect M1 in GaAs layers

Keywords: quantum dots laser structures, gamma radiation, DLTS, defects, nAs/IngaAs

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Authors: Amjad Almunyif, Amra Alhassni, Sultan Alhassan, Maryam Al Huwayz, Saud Alotaibi, Abdulaziz Almalki, Mohamed Henini

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The effect of rapid thermal annealing (RTA) on the optical properties of InAs quantum dots (QDs) grown at an As overpressure of 2x 10⁻⁶ Torr by molecular beam epitaxy (MBE) on (100) and (311)B GaAs substrates was investigated using photoluminescence (PL) technique. PL results showed that for the as-grown samples, the QDs grown on the high index plane (311)B have lower PL intensity and lower full width at half maximum (FWHM) than those grown on the conventional (100) plane. The latter demonstrates that the (311)B QDs have better size uniformity than (100) QDs. Compared with as-grown samples, a blue-shift was observed for all samples with increasing annealing temperature from 600°C to 700°C. For (100) samples, a narrowing of the FWHM was observed with increasing annealing temperature from 600°C to 700°C. However, in (311)B samples, the FWHM showed a different behaviour; it slightly increased when the samples were annealed at 600°C and then decreased when the annealing temperature increased to 700°C. As expected, the PL peak intensity for all samples increased when the laser excitation power increased. The PL peak energy temperature dependence showed a strong redshift when the temperature was increased from 10 K to 120 K. The PL peak energy exhibited an abnormal S-shape behaviour as a function of temperature for all samples. Most samples exhibited a significant enhancement in their activation energies when annealed at 600°C and 700°C, suggesting that annealing annihilated defects created during sample growth.

Keywords: RTA, QDs, InAs, MBE

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Authors: Ibrahim Yakubu Seini, Oluwole Daniel Makinde

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MHD chemically reacting viscous fluid flow towards a vertical surface with slip and convective boundary conditions has been conducted. The temperature and the chemical species concentration of the surface and the velocity of the external flow are assumed to vary linearly with the distance from the vertical surface. The governing differential equations are modeled and transformed into systems of ordinary differential equations, which are then solved numerically by a shooting method. The effects of various parameters on the heat and mass transfer characteristics are discussed. Graphical results are presented for the velocity, temperature, and concentration profiles whilst the skin-friction coefficient and the rate of heat and mass transfers near the surface are presented in tables and discussed. The results revealed that increasing the strength of the magnetic field increases the skin-friction coefficient and the rate of heat and mass transfers toward the surface. The velocity profiles are increased towards the surface due to the presence of the Lorenz force, which attracts the fluid particles near the surface. The rate of chemical reaction is seen to decrease the concentration boundary layer near the surface due to the destructive chemical reaction occurring near the surface.

Keywords: boundary layer, surface slip, MHD flow, chemical reaction, heat transfer, mass transfer

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Authors: S. Yakubu, E. A. Isah

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One of the objectives of the school discipline policy is to instill discipline among students. However, despite the availability of this policy in various secondary schools in Nigeria, there seem to be numerous cases of indiscipline among students, which has become a source of concern to all stakeholders in the education sector. In an attempt to proffer possible solutions to this unending challenge, the study investigated the influence of knowledge and attitude on compliance of secondary school students towards school discipline policy in Ibadan North Local Government Area of Oyo State, Nigeria. The descriptive survey research design was employed to collect the requisite data. The multi-stage sampling procedure was adopted to select 570 respondents as the sample for the study. The data collected were analyzed using statistical measures of Mean, Standard deviation and Pearson Product Moment Correlation. The findings of the study showed that knowledge and compliance of school discipline policy among secondary school students in Ibadan North Local Government Area of Oyo State were significantly related (r =0.330, p<0.05). The study also revealed a significant relationship between attitude and compliance of school discipline policy among secondary school students in Ibadan North Local Government Area of Oyo State (r = 0.593, p<0.05). Based on the findings, it was recommended that school rules and regulations should be emphasized and given more awareness for easy compliance. Also, students should be encouraged to portray a positive attitude towards their respective rules and regulations.

Keywords: knowledge, attitude, compliance, school discipline policy

Procedia PDF Downloads 155

Authors: Arah Abubakar Saidu, Audu Rufai, Abdulkadir Mohammed, Ibrahim Yakubu Umar, Idris Abubakar Mohammed

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The study determined the contents for the maintenance and troubleshooting of an anti-lock braking system for automobile craftsmen in Nigeria. Two research questions were raised and answered and two null hypotheses were formulated and tested at a .05 level of significance. The study adopted a descriptive survey research design. The study was conducted in Federal Capital Territory (FCT), Abuja, Kaduna, Kano, Lagos and Plateau States, Nigeria. The targeted population for the study was 99 consisting of all 43 non-teaching Subject Matter Experts (SMEs). The study utilized the whole population of the study. The instruments used for data collection were Anti-lock Braking System Maintenance and Troubleshooting Contents Questionnaire (ABSMTQ). Mean was used to analyze data that answered research questions and Z-test was used in testing the null hypotheses. Findings revealed, among others, that 81 items as content for the maintenance of ABS and 61 items as content for troubleshooting ABS for automobile craftsmen in Nigeria. Based on the findings of the study, the recommended, among others, that the National Board for Technical Education should include the contents for the maintenance and troubleshooting ABS in Motor Vehicle Mechanic Works curriculum used for training automobile craftsmen through the process of curriculum review in order to equip them with the competencies in troubleshooting and maintenance of ABS.

Keywords: anti-lock braking system, maintenance, troubleshooting, automobile craftsmen

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Authors: M. M. Alhaji, M. Alhassan, A. M. Yahaya

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Soil engineers pay very little or no attention to variation in the mineralogical and consequently, the geotechnical properties of overburden with depth on basement complexes, a situation which can lead to sudden failure of civil engineering structures. Soil samples collected at depths ranging from 0.5m to 4.0m at 0.5m intervals, from a trial pit dogged manually to depth of 4.0m on an overburden over gneiss basement complex, was evaluated for physico-chemical, mineralogical and physical properties. This is to determine the variation of these properties with depth within the profile of the strata. Results showed that sodium amphibolite and feldspar, which are both primary minerals dominate the overall profile of the overburden. Carbon which dominates the lower profile of the strata was observed to alter to gregorite at upper section of the profile. Organic matter contents and cation exchange capacity reduces with increase in depth while lost on ignition and pH were relatively constant with depth. The index properties, as well as natural moisture contents, increases from 0.5m to between 1.0m to 1.5m depth after which the values reduced to constant values at 3.0m depth. The grain size analysis shows high composition of sand sized particles with silts of low to non-plasticity. The maximum dry density (MDD) values are generally relatively high and increases from 2.262g/cm³ at 0.5m depth to 2.410g/cm³ at 4.0m depth while the optimum moisture content (OMC) reduced from 9.8% at 0.5m depth to 6.7% at 4.0m depth.

Keywords: Gneiss basement complex, mineralogical properties, North Central Nigeria, physico-chemical properties, physical properties, overburden soil

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Authors: Muhammad Abubakar Alhassan, Diane Pennington

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Social networking sites have become a space for people to discuss public health issues such as non-suicidal self-injury (NSSI). There are thousands of tweets containing self-harm and self-injury hashtags on Twitter. It is difficult to distinguish between different users who participate in self-injury discussions on Twitter and how their opinions change over time. Also, it is challenging to understand the topics surrounding NSSI discussions on Twitter. We retrieved tweets using #selfham and #selfinjury hashtags and investigated those from the United kingdom. We applied inductive coding and grouped tweeters into different categories. This study used the Latent Dirichlet Allocation (LDA) algorithm to infer the optimum number of topics that describes our corpus. Our findings revealed that many of those participating in NSSI discussions are non-professional users as opposed to medical experts and academics. Support organisations, medical teams, and academics were campaigning positively on rais-ing self-injury awareness and recovery. Using LDAvis visualisation technique, we selected the top 20 most relevant terms from each topic and interpreted the topics as; children and youth well-being, self-harm misjudgement, mental health awareness, school and mental health support and, suicide and mental-health issues. More than 50% of these topics were discussed in England compared to Scotland, Wales, Ireland and Northern Ireland. Our findings highlight the advantages of using the Twitter social network in tackling the problem of self-injury through awareness. There is a need to study the potential risks associated with the use of social networks among self-injurers.

Keywords: self-harm, non-suicidal self-injury, Twitter, social networks

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Authors: Yakubu Nkom Bityong, A. I. Kabido, K. Venkateswarlu

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The influence of branding and consultancy services on sports development and marketing mix has been a matter of interest among coaches athletes and sports managers in Nigeria. Marketers use sports as a promotional vehicle towards attracting customers to their products and services. The use of images, names, and photographs of sports personalities to advertise beverages, cars, and a whole range of other products and services as it is clearly noticed all over the television, radio and print media has generated a lot of argument among consumers who have vested interest and are more drawn to their favorite teams and sports personalities than they are to many company products This paper examines the influence of branding and consultancy services on sports Performance of coaches, athletes and sports managers in Nigeria. From a population of 7,441 made up of coaches, athletes and sports managers, 372 respondents were sampled for the study. A self developed and standardized questionnaire was the instrument used for data collection. One-tailed t-test was used to test the hypothesis. Results revealed that branding and consultancy services influence the performances of coaches, athletes and sports managers in Nigeria. It was concluded that the establishment of the National Institute of Sports (NIS) in Lagos with affiliated sports training programmes in Nigerian Universities is responsible for boosting the performance of sports personalities in Nigeria. It was recommended that National Policy on Sports should be reviewed in order to inculcate new methods and strategies towards enhancing sports development initiatives in the country while stakeholders should intensify regular training and retraining programmes for coaches, athletes and sports managers to update their knowledge and skills.

Keywords: branding, consultancy, sports performance, sports development

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Authors: Yakubu Suleiman, S. A. Musa

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Nigeria is the largest cowpea producer in the world, accounting for about 45%, followed by Brazil with about 17%. Cowpea is grown in Kano, Bauchi, Katsina, Borno in the north, Oyo in the west, and to the lesser extent in Enugu in the east. This study was conducted to determine the input–output relationship of Cowpea production in Kano, Katsina, and Jigawa states of Nigeria. The data were collected with the aid of 1000 structured questionnaires that were randomly distributed to Cowpea farmers in the three states mentioned above of the study area. The data collected were analyzed using regression analysis (Cobb–Douglass production function model). The result of the regression analysis revealed the coefficient of multiple determinations, R2, to be 72.5% and the F ration to be 106.20 and was found to be significant (P < 0.01). The regression coefficient of constant is 0.5382 and is significant (P < 0.01). The regression coefficient with respect to labor and seeds were 0.65554 and 0.4336, respectively, and they are highly significant (P < 0.01). The regression coefficient with respect to fertilizer is 0.26341 which is significant (P < 0.05). This implies that a unit increase of any one of the variable inputs used while holding all other variables inputs constants, will significantly increase the total Cowpea output by their corresponding coefficient. This indicated that farmers in the study area are operating in stage II of the production function. The result revealed that Cowpea farmer in Kano, Jigawa and Katsina States realized a profit of N15,997, N34,016 and N19,788 per hectare respectively. It is hereby recommended that more attention should be given to Cowpea production by government and research institutions.

Keywords: coefficient, constant, inputs, regression

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Authors: Abdullahi Musa, Yakubu Kukure Enebe Ibrahim, Adeshina Gujumbola

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The emergence of multidrug resistance in clinical Escherichia coli has been associated with plasmid-mediated genes. DNA transfer among bacteria is critical to the dissemination of resistance. Plasmids have proved to be the ideal vehicles for dissemination of resistance genes. Plasmids coding for antibiotic resistance were long being recognized by many researchers globally. The study aimed at determining the antibiotic susceptibility pattern of ESBL E. coli isolates claimed to be multidrug resistance using disc diffusion method. Antibacterial activity of the test isolates was carried out using disk diffusion methods. The results showed that, majority of the multidrug resistance among clinical isolates of ESBL E. coli was as a result of acquisition of plasmid carrying antibiotic-resistance genes. Production of these ESBL enzymes by these organisms which are normally carried by plasmid and transfer from one bacterium to another has greatly contributed to the rapid spread of antibiotic resistance amongst E. coli isolates, which lead to high economic burden, increase morbidity and mortality rate, complication in therapy and limit treatment options. To curtail these problems, it is of significance to checkmate the rate at which over the counter drugs are sold and antibiotic misused in animal feeds. This will play a very important role in minimizing the spread of resistance bacterial strains in our environment.

Keywords: Escherichia coli, plasmid, multidrug resistance, ESBL, pan drug resistance

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Authors: Iliya Ibrahim Gimba

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The period between the late 18th and early 19th centuries was characterized by conflict of ethnic nationalities in the Benue valley region. This conflict was exacerbated by the introduction of the Fulani jihad that began in Hausa land into the Benue valley region. Fulani in this region launched the Jihad movement which pushed out some ethnic groups from their natural abode or ancestral home to live a nomad live until they could settle and established a stayed in a particular place. The Chamba were being displaced by the Fulani jihad that took place around Faro deo in about 1809. It was from there that most of the Chamba migrated out, some into the Cameroon republic, while others moved into the Benue valley region. Among those that entered into the Benue valley region are the Sama, Kola, Gayam etc, and could be found in Donga local Government area of Taraba state. Those Chamba clan that later on cameo into the Benue Valley are Pyeri, Kashimbila etc. The sudden movement of the Chamba or migrations into the Jukun territory co-in ceded with the period that the Jihad had already had a severe and consequential effect or impact on the Jukun territory cause by Yakubu Ibrahim of Bzuchi, and Buba Yero of Gombe, and Hamaruwa of Muri Emirate. This ne authorities in Kwararafa Kingdom cut the Jukun King out of contact with Borno and Hausa-land. This paper set to examine the chiefdom that the Chamba established right within the Jukun headquarters of Wukari. Sources to be used are published books, Journals, Archival materials, and M.A. Thesis to enable us know the impact of Chamba migrations on the Jukun territory and reactions of the Jukun’s to this new comers.

Keywords: Chamba people, encroachment, migration, ethnic nationalities

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Authors: Ishaq Alhassan Meriga

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This study examined the phenomenon of mob violence and its implication for peace in Ghana. The study used the archival study of media reports and content analysis of other secondary data as well as eyewitness accounts. The study examined trends and patterns of vigilante violence within the Ghanaian context. Results showed a considerable increase in the occurrence of mob violence within the last 10 years. Theft and robbery emerged as the most frequently suspected crimes for which victims were attacked, while the LGBT community is not left out. Cases of mob violence were most frequently reported in urban areas. This study has shown that the patterns, scope, nature, and implication of mob justice in Ghana are fairly and comparatively similar to those found in other parts of Africa and the globe. Mob violence is identified as undermining the rule of law and thereby infringing on the fundamental human rights of the victims. It is confirmed to have a cycle of effects that is an impediment to the peace of the country. The study underscores the implications of mob violence in terms of disdaining human life and dignity, revisiting our justice systems and punishment procedures, resourcing, and empowering law enforcers to fight the menace of vigilantism. First, the archival study had a limitation regarding missing data. The majority of the cases used for the study lack information mostly on perpetrators and the steps taken by public authorities and security agencies after reports of a mob attack have been lodged with them. The study recommends for further research to be undertaken on the perpetrators and survivors of mob actions in order to get a holistic understanding of the phenomenon. This will give a more comprehensive view of the issue of mob violence in Ghana. From the findings, it can be concluded that mob justice is a social canker in Ghanaian communities, which has a great impact on the peace of the country.

Keywords: LGBT, mob justice, peace, vigilantism

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Authors: Yakubu Abdulai, Kenichi Matsui

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The agricultural industry has faced a variety of challenges in meeting the expanding income demand of the rural population. As a result, rural households must diversify their income sources to meet their income demand. Although income diversification strategies help rural households, it contributes to total household income, and the socio-demographic determinants are not known in the Upper East Region of Ghana. For these reasons, the purpose of this study was to determine the contribution of income diversification strategies to household income and the socio-demographic factors influencing it. We conducted a questionnaire survey among 360 rural households in the Upper East Region of Ghana. We asked about their socio-demographic information, their choice of income diversification strategies, and their remittances through rural-city migration. The questionnaire survey findings demonstrate that the main livelihood income source contributes 22%, and on-farm income diversification contributes the most to household total income (47%), followed by non-farm diversification income (16%) and off-farm diversification income (15%). Calculations from the income diversity index showed that the average income diversification strategy was 0.5 out of 1. The calculation of the income dependence index also showed that the average dependent on a particular source of income was 0.2 out of 1. All the respondents said household members temporarily migrate to contribute to household income through remittances. The results further reveal that their choice of income diversification is influenced by their age, educational background, experience, and farm size. The paper recommends the promotion of rural development policies that increase income-generating activities and educate rural households on how to increase returns from their investment.

Keywords: income diversification, poverty alleviation, rural households, upper east region

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Authors: J. Y. Ijato, A. Adewumi, H. O Yakubu, O. O. Olajide, B. O. Ojo, B. A. Adanikin

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Post-harvest fruit rot pathogens are one of the major factors that are responsible for food security challenges in developing countries like Nigeria. These pathogens also cause fruit food poisoning. Biocidal effects of ethanolic extracts of Khaya grandifoliola, Hyptis suaveolens, Zingiber officinale, Calophyllum inophyllum, Datura stramonium on the mycelia growth of fungal rot pathogens of pineapple fruit was investigated, the ethanolic extracts of these test plants exhibited high significant inhibitory effects on the rot pathogens, the highest ethanolic extract inhibition of Zingiber officinale was on Aspergillus flavus (38.40%) at 1.0g/ml while the least inhibitory effect was on Aspergillus fumigatus (23.10%) at 1.0g/ml, the highest ethanol extract inhibition of Datura stramonium was on Aspergillus tubingensis (24.00%) at 1.0g/ml while the least inhibitory effect was 10.00% on Colletotrichum fruticola at 1.0g/ml, the highest ethanol extract inhibition of Calophyllum inophyllum was on Trichoderma harzianum (18.50%) at 1.0g/ml while the least inhibitory effect was on Aspergillus flavus (15.00%) at 1.0g/ml, the highest ethanol extract inhibition of Hyptis suaveolens was on Aspergillus fumigatus (35.00%) at 1.0g/ml while the least inhibitory effect was on Aspergillus niger (20.00%) at 1.0g/ml, the highest ethanol extract inhibition of Khaya grandifoliola was on Aspergillus flavus (35.00%) at 1.00g/ml while the least inhibitory effect was on Aspergillus fumigates (22.00%) at 1.0g/ml, the antifungal capacity of these test plant extracts on rot causing fungi on pineapple fruit reveals the possibility of their use by farmers and fruit traders as alternative to chemical fungicide that portends great threat to human and environmental health.

Keywords: fruit rot, pathogens, plant extracts, pineapple, food poisoning

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Authors: Ibrahim Alhassan Libata

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This study was carried out to assess attitude of secondary school students towards science and technical education in Yauri metropolis, Kebbi State, Nigeria. The population of the study was 200. Proportionate random sampling method was used in selecting 132 as sample size. Science and technical education is the most powerful forces for change in the world today, and students who hope to have a hand in shaping a better future must participate for their advancements. Four Null hypotheses were generated to guide the conduct of the study, questionnaire was the only instrument used in the study; the instrument was subjected to test-retest reliability. The reliability index of the instrument was 0.69. Overall scores of the Students were analyzed and a mean score was determined, the mean score of students was 85. There were no significant differences between the attitudes of male and female students towards science and technical education. The results also revealed that there was significant difference between the attitude of boding and day school students towards science and technical education, personality constraints of students is one factor militating against the participation of students in science and technical education, socio-economic status of the parents over the years have been the dominant factor of student’s inadequate representation in the field of science and technical education. Based on the findings of this study, the researcher recommended that teachers should motivate students, which they can do through their teaching styles and by showing them the relevance of the learning topics to their everyday lives. Government and the school management should create the learning environment that helps motivate students not only to come to classes but also want to learn and enjoy learning science and technical education, establishment of more Science and Technical Colleges education, more Public enlightenment campaigns to motivate parents and the entire community to support their children in studying science and technical education.

Keywords: attitude, students, science, Yauri

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Authors: Vishnu V. Pillai, Sunil P. Lonkar, Akhil M. Abraham, Saeed M. Alhassan

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An effectual technology for wastewater treatment is a great demand now in order to encounter the water pollution caused by organic pollutants. Photocatalytic oxidation technology is widely used in removal of such unsafe contaminants. Among the semi-conducting metal oxides, robust and thermally stable TiO2 has emerged as a fascinating material for photocatalysis. Enhanced catalytic activity was observed for nanostructured TiO2 due to its higher surface, chemical stability and higher oxidation ability. However, higher charge carrier recombination and wide band gap of TiO2 limits its use as a photocatalyst in the UV region. It is desirable to develop a photocatalyst that can efficiently absorb the visible light, which occupies the main part of the solar spectrum. Hence, in order to extend its photocatalytic efficiency under visible light, TiO2 nanoparticles are often doped with metallic or non-metallic elements. Non-metallic doping of TiO2 has attracted much attention due to the low thermal stability and enhanced recombination of charge carriers endowed by metallic doping of TiO2. Amongst, sulfur doped TiO2 is most widely used photocatalyst in environmental purification. However, the most of S-TiO2 synthesis technique uses toxic chemicals and complex procedures. Hence, a facile, scalable and environmentally benign preparation process for S-TiO2 is highly desirable. In present work, we have demonstrated new and facile solid-state reaction method for S-TiO2 synthesis that uses abundant elemental sulfur as S source and moderate temperatures. The resulting nano-sized S-TiO2 has been successfully employed as visible light photocatalyst in methylene blue dye removal from aqueous media.

Keywords: ecofriendly, nanomaterials, methylene blue, photocatalysts

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Authors: Sulyman Abdulhakeem Olarewaju, S. O. Malomo, M. T. Yakubu, J. O. Akolade

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The ameliorative effect of Celosia argentea var. cristata leaf extract against cadmium (Cd) induced oxidative stress and toxicity in selected tissues of rats was investigated. Toxicity coupled with oxidative stress was induced in rats by oral administration of Cd (8 mg/kg b. wt). Preliminary quantitative phytochemical and in vitro antioxidant analyses showed that the methanolic extract of C. argentea leaves was constituted by polyphenols (5.72%), saponins (3.20%), tannins (0.65%) and cadenolides (0.006%). IC50 of 9800, 7406, and 45.04 μg/ml were recorded for inhibition of linoleic acid oxidation, 2, 2-diphenyl-1-picrylhydrazyl and hydrogen peroxide radicals respectively. Simultaneous administration of C. argentea leaf extract with Cd significantly attenuated Cd-induced elevation of serum enzyme markers such as aspartate and alanine transaminase, alkaline and acid phosphatase as well as γ-glutaryltransferase in a dose-dependent fashion, while their reduced level in the liver were significantly increased. Higher levels of enzymatic antioxidants; superoxide dismutase and catalase activities were observed in the liver, brain, kidney and testes of the Cd-induced rats treated with C. argentea extract, while lipid peroxidation expressed in malondialdehyde concentrations were lower when compared to values in rats administered Cd only. Other Cd-induced toxicity and stress markers in the serum viz. reduced uric acid and albumin levels as well as elevated total and unconjugated bilirubin were attenuated by the extract and their values compared favorably with those animals co-administered cadmium with ascorbic acid. Data from the study showed that oral administration of extract from the leaf C. argentea may ameliorate Cd-induced oxidative stress and toxicity in rats.

Keywords: toxicity, cadmium, celosia, antioxidants, oxidative stress

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Authors: I. Alhassan, A. M. Saddiq, A. G. Gashua, K. K. Gwio-Kura

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The main objective of any irrigation program is the development of an efficient water management system to sustain crop growth and development and avoid physiological water stress in the growing plants. Field experiment to evaluate the effects of some soil moisture conservation practices on yield and water use efficiency (WUE) of maize was carried out in three locations (i.e. Mubi and Yola in the northern Guinea Savannah and Ganye in the southern Guinea Savannah of Adamawa State, Nigeria) during the dry seasons of 2013 and 2014. The experiment consisted of three different irrigation levels (7, 10 and 12 day irrigation intervals), two levels of mulch (mulch and un-mulched) and two tillage practices (no tillage and minimum tillage) arranged in a randomized complete block design with split-split plot arrangement and replicated three times. The Blaney-Criddle method was used for measuring crop evapotranspiration. The results indicated that seven-day irrigation intervals and mulched treatment were found to have significant effect (P>0.05) on grain yield and water use efficiency in all the locations. The main effect of tillage was non-significant (P<0.05) on grain yield and WUE. The interaction effects of irrigation and mulch were significant (P>0.05) on grain yield and WUE at Mubi and Yola. Generally, higher grain yield and WUE were recorded on mulched and seven-day irrigation intervals, whereas lower values were recorded on un-mulched with 12-day irrigation intervals. Tillage exerts little influence on the yield and WUE. Results from Ganye were found to be generally higher than those recorded in Mubi and Yola; it also showed that an irrigation interval of 10 days with mulching could be adopted for the Ganye area, while seven days interval is more appropriate for Mubi and Yola.

Keywords: irrigation, maize, mulching, tillage, savanna

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Authors: Yakubu Suleiman, S. A. Musa

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The research was conducted to determine the physical characteristics of banana fruits that influenced consumer preferences for the fruit in Northern Nigeria. Socio-economic characteristics of the respondents were also identified. Simple descriptive statistics and Hedonic prices model were used to analyze the data collected for socio-economic and consumer preference respectively with the aid of 1000 structured questionnaires. The result revealed the value of R2 to be 0.633, meaning that, 63.3% of the variation in the banana price was brought about by the explanatory variables included in the model and the variables are: colour, size, degree of ripeness, softness, surface blemish, cleanliness of the fruits, weight, length, and cluster size of fruits. However, the remaining 36.7% could be attributed to the error term or random disturbance in the model. It could also be seen from the calculated result that the intercept was 1886.5 and was statistically significant (P < 0.01), meaning that about N1886.5 worth of banana fruits could be bought by consumers without considering the variables of banana included in the model. Moreover, consumers showed that they have significant preference for colours, size, degree of ripeness, softness, weight, length and cluster size of banana fruits and they were tested to be significant at either P < 0.01, P < 0.05, and P < 0.1 . Moreover, the result also shows that consumers did not show significance preferences to surface blemish, cleanliness and variety of the banana fruit as all of them showed non-significance level with negative signs. Based on the findings of the research, it is hereby recommended that plant breeders and research institutes should concentrate on the production of banana fruits that have those physical characteristics that were found to be statistically significance like cluster size, degree of ripeness,’ softness, length, size, and skin colour.

Keywords: analysis, consumers, preference, variables

Procedia PDF Downloads 301

Authors: C. E. Chinma, S. O. Azeez, J. C. Anuonye, O. B. Ocheme, C. M. Yakubu, S. James, E. U. Ohuoba, I. A. Baba

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There is growing interest in the use of rice bran protein in food formulation due to its hypoallergenic protein, high nutritional value and health promoting potentials. For the first time, the amino acid profile, protein digestibility, antioxidant, and functional properties of protein concentrate from some local varieties of rice bran from Nigeria were studied for possible food applications. Protein concentrates were prepared from rice bran and analysed using standard methods. Results showed that protein content of Kwandala, Yardass, Jeep, and Jamila were 69.24%, 69.97%, 68.73%, and 71.62%, respectively while total essential amino acid were 52.71, 53.03, 51.86, and 55.75g/100g protein, respectively. In vitro protein digestibility of protein concentrate from Kwandala, Yardass, Jeep and Jamila were 90.70%, 91.39%, 90.57% and 91.63% respectively. DPPH radical inhibition of protein from Kwandala, Yardass, Jeep, and Jamila were 48.15%, 48.90%, 47.56%, and 53.29%, respectively while ferric reducing ability power were 0.52, 0.55, 0.47 and 0.67mmol TE per gram, respectively. Protein concentrate from Jamila had higher onset (92.57oC) and denaturation temperature (102.13oC), and enthalpy (0.72J/g) than Jeep (91.46oC, 101.76oC, and 0.68J/g, respectively), Kwandala (90.32oC, 100.54oC and 0.57J/g, respectively), and Yardass (88.94oC, 99.45oC, and 0.51J/g, respectively). In vitro digestibility of protein from Kwandala, Yardas, Jeep, and Jamila were 90.70%, 91.39%, 90.57% and 91.63% respectively. Oil absorption capacity of Kwandala, Yardass, Jeep, and Jamila were 3.61, 3.73, 3.40, and 4.23g oil/g sample respectively, while water absorption capacity were 4.19, 4.32, 3.55 and 4.48g water/g sample, respectively. Protein concentrates had low bulk density (0.37-0.43g/ml). Protein concentrate from Jamila rice bran had the highest foam capacity (37.25%), followed by Yardass (34.20%), Kwandala (30.14%) and Jeep (28.90%). Protein concentrates showed low emulsifying and gelling capacities. In conclusion, protein concentrate prepared from these local rice bran varieties could serve as functional ingredients in food formulations and for enriching low protein foods.

Keywords: rice bran protein, amino acid profile, protein digestibility, antioxidant and functional properties

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Authors: Shouji Yujiro, Memei Dukovic, Mist Yakubu

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Fields are important objects of study in algebra since they provide a useful generalization of many number systems, such as the rational numbers, real numbers, and complex numbers. In particular, the usual rules of associativity, commutativity and distributivity hold. Fields also appear in many other areas of mathematics; see the examples below. When abstract algebra was first being developed, the definition of a field usually did not include commutativity of multiplication, and what we today call a field would have been called either a commutative field or a rational domain. In contemporary usage, a field is always commutative. A structure which satisfies all the properties of a field except possibly for commutativity, is today called a division ring ordivision algebra or sometimes a skew field. Also non-commutative field is still widely used. In French, fields are called corps (literally, body), generally regardless of their commutativity. When necessary, a (commutative) field is called corps commutative and a skew field-corps gauche. The German word for body is Körper and this word is used to denote fields; hence the use of the blackboard bold to denote a field. The concept of fields was first (implicitly) used to prove that there is no general formula expressing in terms of radicals the roots of a polynomial with rational coefficients of degree 5 or higher. An extension of a field k is just a field K containing k as a subfield. One distinguishes between extensions having various qualities. For example, an extension K of a field k is called algebraic, if every element of K is a root of some polynomial with coefficients in k. Otherwise, the extension is called transcendental. The aim of Galois Theory is the study of algebraic extensions of a field. Given a field k, various kinds of closures of k may be introduced. For example, the algebraic closure, the separable closure, the cyclic closure et cetera. The idea is always the same: If P is a property of fields, then a P-closure of k is a field K containing k, having property, and which is minimal in the sense that no proper subfield of K that contains k has property P. For example if we take P (K) to be the property ‘every non-constant polynomial f in K[t] has a root in K’, then a P-closure of k is just an algebraic closure of k. In general, if P-closures exist for some property P and field k, they are all isomorphic. However, there is in general no preferable isomorphism between two closures.

Keywords: field theory, mechanic maths, supertech, rolltech

Procedia PDF Downloads 340

Authors: Ramatu I. Sha’aba, Mathias A. Chia, Abdullahi B. Alhassan, Yisa A. Gana, Ibrahim M. Gadzama

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Globally, Diclofenac (DLC) and Ibuprofen (IBU) are the most prescribed drugs due to their antipyretic and analgesic properties. They are, however, highly toxic at elevated doses, with the involvement of an already described oxidative stress pathway. As a result, there is rising concern about the ecological fate of analgesics on non-target organisms such as Daphnia magna and Phytoplankton species. Phytoplankton is a crucial component of the aquatic ecosystem that serves as the primary producer at the base of the food chain. However, the increasing presence and levels of micropollutants such as these analgesics can disrupt their community structure, dynamics, and ecosystem functions. This study presents a comprehensive series of the physiology, antioxidant response, immobilization, and risk assessment of Diclofenac and Ibuprofen’s effects on Daphnia magna and the Phytoplankton community using a laboratory approach. The effect of DLC and IBU at 27.16 µg/L and 20.89 µg/L, respectively, for a single exposure and 22.39 µg/L for combined exposure of DLC and IBU for the experimental setup. The antioxidant response increased with increasing levels of stress. The highest stressor to the organism was 1000 µg/L of DLC and 10,000 µg/L of IBU. Peroxidase and glutathione -S-transferase activity was higher for Diclofenac + Ibuprofen. The study showed 60% and 70% immobilization of the organism at 1000 g L-1 of DLC and IBU. The two drugs and their combinations adversely impacted Phytoplankton biomass with increased exposure time. However, combining the drugs resulted in more significant adverse effects on physiological and pigment content parameters. The risk assessment calculation for the risk quotient and toxic unit of the analgesic reveals from this study was RQ Diclofenac = 8.41, TU Diclofenac = 3.68, and RQ Ibuprofen = 718.05 and TU Ibuprofen = 487.70. Hence, these findings demonstrate that the current exposure concentrations of Diclofenac and Ibuprofen can immobilize D. magna. This study shows the dangers of multiple drugs in the aquatic environment because their combinations could have additive effects on the structure and functions of Phytoplankton and are capable of immobilizing D. magna.

Keywords: algae, analgesic drug, daphnia magna, toxicity

Procedia PDF Downloads 48

Authors: Bernard Kumi-Boateng, Issaka Yakubu

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Forest fire, which is, an uncontrolled fire occurring in nature has become a major concern for the Forestry Commission of Ghana (FCG). The forest fires in Ghana usually result in massive destruction and take a long time for the firefighting crews to gain control over the situation. In order to assess the effect of forest fire at local scale, it is important to consider the role fire plays in vegetation composition, biodiversity, soil erosion, and the hydrological cycle. The occurrence, frequency and behaviour of forest fires vary over time and space, primarily as a result of the complicated influences of changes in land use, vegetation composition, fire suppression efforts, and other indigenous factors. One of the forest zones in Ghana with a high level of vegetation stress is the Goaso forest area. The area has experienced changes in its traditional land use such as hunting, charcoal production, inefficient logging practices and rural abandonment patterns. These factors which were identified as major causes of forest fire, have recently modified the incidence of fire in the Goaso area. In spite of the incidence of forest fires in the Goaso forest area, most of the forest services do not provide a cartographic representation of the burned areas. This has resulted in significant amount of information being required by the firefighting unit of the FCG to understand fire risk factors and its spatial effects. This study uses Remote Sensing and Geographic Information System techniques to develop a fire risk hazard model using the Goaso Forest Area (GFA) as a case study. From the results of the study, natural forest, agricultural lands and plantation cover types were identified as the major fuel contributing loads. However, water bodies, roads and settlements were identified as minor fuel contributing loads. Based on the major and minor fuel contributing loads, a forest fire risk hazard model with a reasonable accuracy has been developed for the GFA to assist decision making.

Keywords: forest, GIS, remote sensing, Goaso

Procedia PDF Downloads 425

Authors: S. Vijay Kumar, Kishore K. Jena, Saeed M. Alhassan

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Elemental sulfur is currently produced on the level of 70 million tons annually by petroleum refining, majority of which is used in the production of sulfuric acid, fertilizer and other chemicals. Still, over 6 million tons of elemental sulfur is generated in excess, which creates exciting opportunities to develop new chemistry to utilize sulfur as a feedstock for polymers. Development of new polymer composite materials using sulfur is not widely explored and remains an important challenge in the field. Polymer nanocomposites prepared by carbon nanotube, graphene, silica and other nanomaterials were well established. However, utilization of sulfur as filler in the polymer matrix could be an interesting study. This work is to presents the possibility of utilizing elemental sulfur as reinforcing fillers in the polymer matrix. In this study we attempted to prepare polypropylene/sulfur nanocomposite. The physical, mechanical and morphological properties of the newly developed composites were studied according to the sulfur loading. In the sample preparation, four levels of elemental sulfur loading (5, 10, 20 and 30 wt. %) were designed. Composites were prepared by the melt mixing process by using laboratory scale mini twin screw extruder at 180°C for 15 min. The reaction time and temperature were maintained constant for all prepared composites. The structure and crystallization behavior of composites was investigated by Raman, FTIR, XRD and DSC analysis. It was observed that sulfur interfere with the crystalline arrangement of polypropylene and depresses the crystallization, which affects the melting point, mechanical and thermal stability. In the tensile test, one level of test temperature (room temperature) and crosshead speed (10 mm/min) was designed. Tensile strengths and tensile modulus of the composites were slightly decreased with increasing in filler loading, however, percentage of elongation improved by more than 350% compared to neat polypropylene. The effect of sulfur on the morphology of polypropylene was studied with TEM and SEM techniques. Microscope analysis revels that sulfur is homogeneously dispersed in polymer matrix and behaves as single phase arrangement in the polymer. The maximum elongation for the polypropylene can be achieved by adjusting the sulfur loading in the polymer. This study reviles the possibility of using elemental sulfur as a solid plasticizer in the polypropylene matrix.

Keywords: crystallization, elemental sulfur, morphology, thermo-mechanical properties, polypropylene, polymer nanocomposites

Procedia PDF Downloads 316

Authors: A. G. Gashua, T. T. Bello, I. Alhassan, K. K. Gwiokura

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Weeds are known to interfere seriously with crop growth, thereby affecting the productivity and quality of crops. Crops are also known to compete for natural growth resources if they are not adequately spaced, also affecting the performance of the growing crop. Farmers grow cowpea in mixtures with cereals and this is known to affect its yield. For this reason, a field experiment was conducted at Yobe State College of Agriculture Gujba, Damaturu station in the 2014 and 2015 rainy seasons to determine the appropriate intra row spacing and weeding regime for optimum growth and yield of cowpea (Vigna unguiculata L.) in pure stand in Sudan Savanna ecology. The treatments consist of three levels of spacing within rows (20 cm, 30 cm and 40 cm) and four weeding regimes (none, once at 3 weeks after sowing (WAS), twice at 3 and 6WAS, thrice at 3WAS, 6WAS and 9WAS); arranged in a Randomized Complete Block Design (RCBD) and replicated three times. The variety used was the local cowpea variety (white, early and spreading) commonly grown by farmers. The growth and yield data were collected and subjected to analysis of variance using SAS software, and the significant means were ranked by Students Newman Keul’s test (SNK). The findings of this study revealed better crop performance in 2015 than in 2014 despite poor soil condition. Intra row spacing significantly influenced vegetative growth especially the number of main branches, leaves and canopy spread at 6WAS and 9WAS with the highest values obtained at wider spacing (40 cm). The values obtained in 2015 doubled those obtained in 2014 in most cases. Spacing also significantly affected the number of pods in 2015, seed weight in both years and grain yield in 2014 with the highest values obtained when the crop was spaced at 30-40 cm. Similarly, weeding regime significantly influenced almost all the growth attributes of cowpea with higher values obtained from where cowpea was weeded three times at 3-week intervals, though statistically similar results were obtained even from where cowpea was weeded twice. Weeding also affected the entire yield and yield components in 2015 with the highest values obtained with increase weeding. Based on these findings, it is recommended that spreading cowpea varieties should be grown at 40 cm (or wider spacing) within rows and be weeded twice at three-week intervals for better crop performance in related ecologies.

Keywords: intra-row spacing, local cowpea, Nigeria, weeding

Procedia PDF Downloads 188

Authors: Mmatladi D. Mnguni, Mustapha Mohammed, George Y. Mahama, Alhassan L. Abdulai, Felix D. Dakora

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Industrial-based nitrogen (N) fertilizers are justifiably credited for the current state of food production across the globe, but their continued use is not sustainable and has an adverse effect on the environment. The search for greener and sustainable technologies has led to an increase in exploiting biological systems such as legumes and organic amendments for plant growth promotion in cropping systems. Although the benefits of legume rotation with cereal crops have been documented, the full benefits of soybean-sorghum rotation systems have not been properly evaluated in Africa. This study explored the benefits of soybean-sorghum rotation through assessing N₂ fixation and water-use efficiency of soybean in rotation with sorghum with and without organic and inorganic amendments. The field trials were conducted from 2017 to 2020. Sorghum was grown on plots previously cultivated to soybean and vice versa. The succeeding sorghum crop received fertilizer amendments [organic fertilizer (5 tons/ha as poultry litter, OF); inorganic fertilizer (80N-60P-60K) IF; organic + inorganic fertilizer (OF+IF); half organic + inorganic fertilizer (HIF+OF); organic + half inorganic fertilizer (OF+HIF); half organic + half inorganic (HOF+HIF) and control] and was arranged in a randomized complete block design. The soybean crop succeeding fertilized sorghum received a blanket application of triple superphosphate at 26 kg P ha⁻¹. Nitrogen fixation and water-use efficiency were respectively assessed at the flowering stage using the ¹⁵N and ¹³C natural abundance techniques. The results showed that the shoot dry matter of soybean plants supplied with HOF+HIF was much higher (43.20 g plant-1), followed by OF+HIF (36.45 g plant⁻¹), and HOF+IF (33.50 g plant⁻¹). Shoot N concentration ranged from 1.60 to 1.66%, and total N content from 339 to 691 mg N plant⁻¹. The δ¹⁵N values of soybean shoots ranged from -1.17‰ to -0.64‰, with plants growing on plots previously treated to HOF+HIF exhibiting much higher δ¹⁵N values, and hence lower percent N derived from N₂ fixation (%Ndfa). Shoot %Ndfa values varied from 70 to 82%. The high %Ndfa values obtained in this study suggest that the previous year’s organic and inorganic fertilizer amendments to sorghum did not inhibit N₂ fixation in the following soybean crop. The amount of N-fixed by soybean ranged from 106 to 197 kg N ha⁻¹. The treatments showed marked variations in carbon (C) content, with HOF+HIF treatment recording the highest C content. Although water-use efficiency varied from -29.32‰ to -27.85‰, shoot water-use efficiency, C concentration, and C:N ratio were not altered by previous fertilizer application to sorghum. This study provides strong evidence that previous HOF+HIF sorghum residues can enhance N nutrition and water-use efficiency in nodulated soybean.

Keywords: ¹³C and ¹⁵N natural abundance, N-fixed, organic and inorganic fertilizer amendments, shoot %Ndfa

Procedia PDF Downloads 137

Authors: Sunil P. Lonkar, Vishnu V. Pillai, Saeed Alhassan

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Design and development of highly efficient, inexpensive, and long-term stable earth-abundant electrocatalysts hold tremendous promise for hydrogen evolution reaction (HER) in water electrolysis. The 2D transition metal dichalcogenides, especially molybdenum disulfide attracted a great deal of interests due to its high electrocatalytic activity. However, due to its poor electrical conductivity and limited exposed active sites, the performance of these catalysts is limited. In this context, a facile and scalable synthesis method for fabrication nanostructured electrocatalysts composed 3D graphene porous aerogels supported with MoS₂ and WS₂ is highly desired. Here we developed a highly active and stable electrocatalyst catalyst for the HER by growing it into a 3D porous architecture on conducting graphene. The resulting nanohybrids were thoroughly investigated by means of several characterization techniques to understand structure and properties. Moreover, the HER performance of these 3D catalysts is expected to greatly improve in compared to other, well-known catalysts which mainly benefits from the improved electrical conductivity of the by graphene and porous structures of the support. This technologically scalable process can afford efficient electrocatalysts for hydrogen evolution reactions (HER) and hydrodesulfurization catalysts for sulfur-rich petroleum fuels. Owing to the lower cost and higher performance, the resulting materials holds high potential for various energy and catalysis applications. In typical hydrothermal method, sonicated GO aqueous dispersion (5 mg mL⁻¹) was mixed with ammonium tetrathiomolybdate (ATTM) and tungsten molybdate was treated in a sealed Teflon autoclave at 200 ◦C for 4h. After cooling, a black solid macroporous hydrogel was recovered washed under running de-ionized water to remove any by products and metal ions. The obtained hydrogels were then freeze-dried for 24 h and was further subjected to thermal annealing driven crystallization at 600 ◦C for 2h to ensure complete thermal reduction of RGO into graphene and formation of highly crystalline MoS₂ and WoS₂ phases. The resulting 3D nanohybrids were characterized to understand the structure and properties. The SEM-EDS clearly reveals the formation of highly porous material with a uniform distribution of MoS₂ and WS₂ phases. In conclusion, a novice strategy for fabrication of 3D nanostructured MoS₂-WS₂/graphene is presented. The characterizations revealed that the in-situ formed promoters uniformly dispersed on to few layered MoS₂¬-WS₂ nanosheets that are well-supported on graphene surface. The resulting 3D hybrids hold high promise as potential electrocatalyst and hydrodesulfurization catalyst.

Keywords: electrocatalysts, graphene, transition metal chalcogenide, 3D assembly

Procedia PDF Downloads 108