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Evaluation of Some Selected Metals in Rice Cultivated in Four Local Government Areas in Enugu State, nigeria

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Journal of Geoscience and Environment Protection 2023年第11期11卷 141-150页

作者： Christopher O. Alisa Samuel C. nwobodo edith n. Alisa Peter C. okeke Ali Bilar Jailen Doyle Lovell Agwaramgbo Department of Chemistry Federal University of Technology Owerri Nigeria Department of Zoology and Environmental Biology University of Nigeria Nsukka Nigeria Opec Research Consult Awka Nigeria Chemistry Department Dillard University New Orleans Louisiana USA

In this study, we investigated the presence of Zn, Fe, Cu, and Ca in rice cultivated in four local government areas (nkanu East, Aninri, Uzo Uwani, Isi Uzo) within Enugu state, nigeria. We employed an Atomic Absorption Spectrometer with an air acetylene flame to analyze these metals after digesting the rice samples. Risk assessment studies were carried out to determine any potential health risk to consumers by evaluating the estimated daily intake (EDI), the target hazard quotient (THQ) and hazard index (HI). The average concentration (mg/kg) of trace metals in the rice samples was within the acceptable limits established by FAO/WHO. Specifically, Zn ranged from 0.265 to 0.632 mg/kg, Fe from 2.73 to 4.131 mg/kg, Cu from 0.205 to 4.131 mg/kg, and Ca from 9.718 to 12.150 mg/kg. There were no statistically significant differences in metal concentrations among the various locations. Consequently, the rice analyzed in this study can be considered safe for consumption. The calculated EDI (mg/kg-day) values were below the maximum tolerable daily intake thresholds. THQ values also fell within safe levels, and the HI values were less than 1, signifying no potential health risks associated with consuming rice from these locations. In conclusion, there is no significant non-carcinogenic health risk associated with exposure to trace metals through the consumption of rice from these areas.

关键词： Trace Metals Rice Risk Assessment Target Hazard Quotient Hazard Index Enugu

Photometric Study of Three Short-Period Eclipsing Binaries from the ASAS Catalogue

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International Journal of Astronomy and Astrophysics 2013年第2期3卷 123-130页

作者： J.A.Obu P.n.okeke Department of Physics University of CalabarCalabarNigeria Centre for Basic Space Science University of NigeriaNsukkaNigeria

We present the results of our study of three previously unstudied short-period eclipsing binaries, namely: ASAS 110609 ﹣ 2045.3, ASAS105331 ﹣ 7424.7, and ASAS 130057 + 2120.3. Using the visual (V)-band data obtained from the ASAS catalogue, the orbital and physical parameters of the systems were derived for the first time using the Wilson-Divenney (WD) codes. Our investigation revealed that ASAS 110609 ﹣ 2045.3 is a near-contact binary star of the W Uma type having an angle of inclination of 80° ± 1, a mass ratio of about 0.5, an orbital period of 0.2933 ± 0.0130 days, and an effective temperature in the range of 5800 K - 6200 K, making it a G2V-F7V spectral system. ASAS 105331 ﹣ 7424.7 was established to be an over-contact binary system of the W Uma type, inclined at 86° ± 2 to the line of sight, having a mass ratio of about 0.9, a period of 0.4825 ± 0.0002, and an effective temperature in the range of 5200 K - 5300 K, making it a K2V-K0V spectral system. A third light factor of just 0.1 was established for the system, however, no evidence of starspots or discs was inferred for either component. ASAS 130,057 + 2120.3 is a W Uma binary having a mass ratio of about 0.6 in a state of marginal contact. Its orbital inclination is 55° ± 1;the effective temperature is in the range of 6200 K - 6500 K, making it a F7V-F5V stellar system. The system showed evidence of third light, with a third light factor of 0.6, however, the presence of spots or discs could not be established for either component. The deduced period was 0.8930 ± 0.0014 days. none of the systems showed any evidence of the O’Connell effect on either component.

关键词： Binaries Eclipsing-Stars Starspots-Stars Fundamental Parameters-Individual ASAS 110609-2045.3 ASAS 105331-7424.7 ASAS 130057+2120.3

Markov Chain Approach to Projection of Secondary School Enrolment and Projection of Teachers

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Open Journal of Statistics 2018年第3期8卷 533-555页

作者： M. n. Egbo D. C. Bartholomew J. U. okeke E. n. okeke Department of Statistics Federal University of Technology Owerri Owerri Nigeria Leadway Assurance Company Limited Lagos Nigeria Department of Mathematics and Statistics Federal University Wukari Nigeria

An enrolment projection model based on the Markov Chain is developed for Apostolic Faith Secondary School, Akwa Ibom State, nigeria. Six years of data (between 2008/2009-2013/2014 academic sessions) of student enrolment at the school were studied. The study reveals that the enrolments through various grades are not stable and orderly. The model is helpful for the school’s future planning in matters regarding secondary students’ enrolment.

关键词： Markov Chain Stationary Length of Stay Estimation of Teachers Future Grade Size

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使用热返矿提高烧结机生产率

烧结球团 1990年第5期15卷 53-58页

作者： S.I.okeke F.n.Okoye 李寿宝

做了关于使用热返矿提高烧结机生产率的实验。实验中,混合料的热返矿添加用了不同的方法:1)在混合,加水,制粒前加入。2)在混匀、制粒后加入。3)把部分热返矿按不同比例分出,在制粒前加入,而其余的在制粒后加入。热返矿的温度在100～100... 详细信息

做了关于使用热返矿提高烧结机生产率的实验。实验中,混合料的热返矿添加用了不同的方法:1)在混合,加水,制粒前加入。2)在混匀、制粒后加入。3)把部分热返矿按不同比例分出,在制粒前加入,而其余的在制粒后加入。热返矿的温度在100～1000℃范围内不等。通过试验发现,在温度为200～400℃和800～1000℃范围内,当将热返矿的90%添加在已经混匀制粒的烧结料中,而剩余部分即10%添加于混合之前时,产率最大。而在温度为400～600℃时,却是将热返矿的60%添加在混合制粒后的烧结料中,而其余的40%添加在混合前的烧结料中效果较好。另外还发现,在温度为900℃以上,热返矿的80%～90%添加在已经混匀制粒的烧结料中的条件下,有微量金属铁出现。

关键词：热返矿烧结机生产率

Geospatial Technology Potentials in Reawakening the Consciousness of Soil Distribution in nigeria’s north-Central Region and Mediating the Herdsmen-Farmers Conflicts

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Journal of Geoscience and Environment Protection 2019年第2期7卷 156-175页

作者： Ugonna C. nkwunonwo Francis I. okeke Emmanuel n. Chiemelu Elijah S. Ebinne Department of Geoinformatics & Surveying University of Nigeria Enugu Campus Enugu Nigeria

The pervasive herdsmen-farmers conflicts in the north-central region of nigeria have changed the narrative of nigeria’s enduring ethnic crises to ideologies, which are in-controvertibly sinister. The consequences of this tension, which has defied possible military responses, political, religious and cultural strategies are potentially devastating, not just for nigeria, but the whole of West African region. Since the particular nature of these conflicts increasingly highlights the significance and inevitability of land resources for crops farming and cattle rearing, it is imperative to create awareness of the elemental nature of soils, especially their diversities in these conflict-prone areas. This study’s objective was to produce a Geographic Information System (GIS) based digital soil map (DSM) of the north-central region of nigeria, and to delineate soil distribution and unique properties. Based on this study, the DSM offers a quick access to quantitative soil data covering the study area. It indicates that soil mapping units 15d, 18d and 24b are dominant, and constitute about 40% of the local arable lands. The broad pattern of distribution of these soils reflects both the climatic conditions and the geological structure of the region. The soils are highly weathered with limited capacities to supply essential nutrients needed by crop plants. These issues raise a number of questions, most of which focuses on the best possible way to maximize these soils to accommodate both crop farming and cattle rearing. It is our hope that taking the advantage of GIS to stimulate the knowledge and consciousness of soil distribution in the region will place the weight where it is appropriate in terms of food security through crops production and cattle rearing, and hence forge a more realistic pathway to reconciliation and conflict resolution.

关键词： Herdsmen Sedentary Farmers north-Central Region of nigeria GIS Digital Soil Map Food Security Conflict Resolution

Toxicity and phyto-bioactive constituent of Ficus aurea L. leaf extract: A trado-medicinal herb used in southeastern nigeria

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Clinical Traditional Medicine and Pharmacology 2024年第4期5卷 54-64页

作者： Sonachi nnedimma okeke Chinyere Godwin Chinyere Okezie Emmanuel Department of Biochemistry Abia State UniversityUturuPMB 2000Uturu Abia StateNigeria Department of Animal Sciences College of FoodAgricultural and Environmental Sciencesthe Ohio State UniversityWoosterOH 44691US

Background:The intrinsic adroitness of medicinal plants as a therapy for several maladies is well-documented in African Herbal *** of Ficus aurea L.(Moraceae)are commonly used in folkloric medicine in southeastern nigeria and other areas of the world to treat malaria,dermatitis,circulatory and intestinal parasitic health ***:The aim of the study was to explore the phytochemical composition and potential toxicity of the ethanolic leaf extract of *** L.(herein afterwards referred to as ELEFA)in albino rats of both ***:Gas chromatography mass spectrometry(GC–MS)was performed to analyze the chemical constituents of *** the acute toxicity study,a single oral dose of up to 5000 mg/kg ELEFA was *** the sub-acute toxicity study,rats were randomly assigned to individual cages to eschew *** groups(A2-A4)and female groups(B2-B4)were administered varying doses of ELEFA(250,500,750 mg/kg)for 28 days,while control groups A1 and B1 received 1 mL/kg of distilled *** analytical procedures were utilized to evaluate the biochemical and haematological profiles,as well as liver and kidney ***:The GC–MS analysis identified 13 phyto-compounds,six of which possess known bioactive and pharmacological *** bioactive compounds include gamma-dodecalactone,n-hexadecanoic acid,methyl stearate,9,12-octadecadienoic acid,oleic acid,octadecanoic *** the acute toxicity,no death was recorded within 24 h following oral administration of ***,haematological and renal biomarkers remained unaltered post-ELEFA ***,elevated levels of serum aspartate and alanine transaminases were detected in ELEFA-treated groups,indicating potential hepatotoxicity.A reduction in atherogenic lipid markers and a dose-dependent elevation in antioxidant concentrations were observed,suggesting a nuanced impact on oxidative ***:The study emphasized caution reg

关键词： Antioxidant Ficus aurea Phytochemical Toxicity Trado-medicine

Propulsion Shaft and Gearbox Failure in Marine Vessels: A Duration Model Analysis

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Journal of Transportation Technologies 2020年第4期10卷 291-305页

作者： D. E. Onwuegbuchunam I. C. Ogwude C. C. Igboanusi K. O. okeke n. n. Azian Department of Maritime Management Technology Federal University of Technology Owerri Nigeria Department of Transport Management Technology Federal University of Technology Owerri Nigeria Strauz Marine & Engineering Ltd. Federal Ocean Terminal (FOT) Onne Nigeria

The need to mitigate downtime in marine vessels arising from propulsion system failures has led ship operating companies to devote enormous resources for research based solutions. This paper applied duration models to determine failure probabilities of shaft and gearbox systems in service boats. Using dockyard’s event history data on boat repairs and maintenance, we applied Kaplan Meier hazard and survival curves to analyse probability of failure of shaft and gearbox systems in supply, crew and tug boats. We found that average time to shaft and gearbox failure was 8.33, 5.23 and 5.21 months for tug, supply and crew boats respectively. The hazard plots however, showed that supply boats had higher probability of failure than crew boats and then tug boats in that order. Further analysis using Cox regression model showed that the boats’ shaft and gearbox system failures were significantly affected by level of lubrication oil, stress corrosion cracking and impacts on the propulsion system’s components. The paper proposes thatn> design of maintenance

关键词： Shaft and Gearbox Failure Propulsion System Hazard Rates Survival Analysis Service Boats

Leafy Vegetables as Potential Pathways to Heavy Metal Hazards

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Journal of Agricultural Chemistry and Environment 2019年第1期8卷 23-32页

作者： C. E. Anarado C. J. O. Anarado M. O. okeke C. E. Ezeh n. L. Umedum P. C. Okafor Department of Pure and Industrial Chemistry Nnamdi Azikiwe University Awka Nigeria

The effect of anthropogenic activity relating to industrial and economic development has had a detrimental impact on the environment and human health, and hence the need for continued research. Five common African vegetables—Murraya koenigii, Ocimum gratissimum, Amaranthus hybridus, Capsicum annuum and Moringa oleifera were used to study absorption of Lead, Cadmium, Cobalt and Zinc from soils inoculated with metal ions. 0.1 M and 0.5 M solutions of the metal ions were used in the inoculation. Each of the plants was collected in the first instance at 8 weeks, and then at 10 weeks of inoculating. Atomic Absorption spectrophotometer was used to determine the metal ions concentrations absorbed in the plants. Cd2+ was most and Moringa oleifera the least absorbed of the four metal ions, with a highest value of 34.801 ± 0.805 mg/kg occurring in Capsicum annuum. Co2+ was the least absorbed of the four metal ions, Amaranthus hybridus showed highest absorption of Co2+ with mean absorption values of 5.566 ± 0.324 mg/kg and 5.670 ± 0.210 mg/kg for 0.1 M and 0.5 M solution of Co2+ respectively. Ocimum gratissimum absorbed Pb2+ most with the highest mean absorption of 5.290 ± 0.180 mg/kg and 6.354 ± 0.366 mg/kg for 0.1 M and 0.5 M respectively. Absorption increased as the concentration of the inoculant solution increased for all the plants, and decreased on moving from 8 weeks’ to 10 weeks’ for all the plants except Moringa oleifera. This could as a result of Phytovolatilization against the report of Padmavathiamma and Li, 2007 [1] that phytovolatilization occurs in As, Hg and Se. Ocimum gratissimum showed highest absorption with the mean value of 9.334 ± 0.312 mg/kg, when the inoculants concentration increased to 0.5 M, Capsicum annuum showed highest absorption with mean absorption value of 9.916 ± 0.614 mg/kg at 10th week. Also absorption increased as the concentration of the inoculant solution increased, and also on moving from 8 weeks’ to 10 weeks’ for all the plants. From th

关键词： Heavy Metals Ocimum gratissimum Murraya koenigii Capsicum annuum Amaranthus hybridus Moringa oleifera

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玻色-爱因斯坦凝聚态间的光学介导纠缠

华东师范大学学报（自然科学版） 2022年第2期 93-105页

作者：高帅 PREST Matthew ILO-okeke Ebubechukwu O KOnDAPPAn Manikandan ARISTIZABAL-ZULUAGA Juan E IVAnnIKOV Valentin BYRnES Tim 华东师范大学精密光谱科学与技术国家重点实验室上海200241 上海纽约大学物理系上海200122 奥维里联邦科技大学理学院物理系伊莫州460001尼日利亚安蒂奥基亚大学物理研究所精密科学与自然科学系麦德林05001000哥伦比亚华东师范大学-纽约大学物理联合研究中心上海200062 国家信息研究所东京101-8430日本纽约大学物理系纽约10003美国

着重研究了一种在玻色-爱因斯坦凝聚态(Bose-Einstein Condensate,BEC)之间产生光学介导纠缠的方案.该方案使用量子非破坏性哈密顿量,并将BEC置于马赫-曾德(Mach-Zehnder)构型中.结果表明,通过对光进行测量,可以诱导产生纠缠态.还特别... 详细信息

着重研究了一种在玻色-爱因斯坦凝聚态(Bose-Einstein Condensate,BEC)之间产生光学介导纠缠的方案.该方案使用量子非破坏性哈密顿量,并将BEC置于马赫-曾德(Mach-Zehnder)构型中.结果表明,通过对光进行测量,可以诱导产生纠缠态.还特别分析了纠缠态在退相干作用下的效应.研究表明,该纠缠态的行为表现对于原子与光的作用时间较为敏感:当相互作用时间T≤1/√n时,该纠缠态相对稳定;当相互作用时间T>1/√n时,该纠缠态则相对脆弱.

关键词：玻色-爱因斯坦凝聚态量子非破坏性测量双自旋纠缠态退相干