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Design and Performance Evaluation of a Sustained Load Dual Grip Creep Testing Machine

Journal of Minerals and Materials Characterization and Engineering 2014年第6期2卷 531-538页

作者： Kenneth Kanayo Alaneme Bethel Jeremiah Bamike godwin Omlenyi Department of Metallurgical and Materials Engineering Federal University of Technology Akure Nigeria Department of Mining and Metallurgical Engineering University of Namibia Ongwediva Engineering Campus Ongwediva Namibia

The design and performance evaluation of a sustained load creep testing machine was undertaken in this research. The design was motivated by the need to make locally available, a cost effective, technically efficient, and easily operated creep testing facility;for creep behaviour studies of materials. Design drawings and purchase of materials and components for the design were undertaken after thorough evaluation of the following design and materials selection criteria: design principle and theory, local availability of raw materials and components required for the design, material properties, cost of materials and design, ease of utilization and maintenance, and basis of testing and data capture. The machine casing and frame, heating chamber (consisting of the furnace and a dual specimen mounting stage), load lever and hanger system, and the electro-technical components;were fabricated and coupled following the produced design specifications. The machine was tested and its performance was assessed using its heating efficiency, repeatability and reproducibity of experimental test results, maintainability and cost-effectiveness as criteria. It was observed from repeat tests that the machine has the capacity of generating reliable data for computing creep strain-time results. The efficiency and temperature regulating capacity of the heating unit of the machine were also observed to be very satisfactory. The cost of the design was about 112,000 Naira ($700.00) which is cheaper in comparison to similar commercial creep testing machines from abroad. The machine was also found not to pose maintenance or repairs challenges.

关键词： Creep Failure Analysis Machine Design Strain Rate Sustained Load Fracture

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Stability Study of a 23 MVA Turbine Generator

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Energy and Power Engineering 2022年第8期14卷 313-326页

作者： godwin Effiong Priye Kenneth Ainah Nduka W. Aguiyi Department of Physics University of Calabar Calabar Nigeria Department of Electrical/Electronics Faculty of Engineering Niger Delta University Bayelsa Nigeria Department of Electrical/Electronics Faculty of Engineering Federal University Otueke Bayelsa Nigeria

Power system stability is a very important issue in power system engineering because a decrease in the stability margins can cause unacceptable operating conditions, which leads to frequent failures. In this paper, SKM POWER TOOLS PTW-32 Version 4.***.2.0 was used to study different Stability recovery tests after a medium voltage short circuit fault on a turbine generator in the power system. The analysis focused on the generator electrical and mechanical powers stability recovery test, generator speed stability recovery test, excitation voltage stability recovery test, bus voltage and bus frequency stability recovery test. In our study, when the introduced fault was cleared after 0.5 s, it reveals that the recovery rate of electrical power was much faster than that of mechanical power. Also, the results reveal that it took about 10 seconds for the turbine speed to stabilize while it took fewer seconds for the frequency to stabilize.

关键词： Power System Stability Turbine Generator Power System Limit

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Physico-Chemical Characteristics and Heavy Metals in Groundwater Bassambiri-Nembe, Bayelsa State, Nigeria

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International Journal of Geosciences 2023年第11期14卷 1065-1084页

作者： Onyema Isukul Amararu godwin Jeremiah Udom Richmond Uwanemesor Ideozu Institute of Natural Resources Environment & Sustainable Development (INRES) University of Port Harcourt Port Harcourt Nigeria Department of Geology Faculty of Science University of Port Harcourt Port Harcourt Nigeria

The study is focused on the post impact of oil spill contamination of groundwater in Bassambiri Nembe Bayelsa State. Groundwater samples were sampled from hand dug wells from eight stations including the control point for physico-chemical investigation using sterilized glass bottles. Standard methods were used for the analyses. The result of physico-chemical parameters analyzed shows that the values of the groundwater pH ranged between 5.90 - 6.35, electrical conductivity between 80.39 - 89.23 μS/cm, Salinity 23.3 - 28.69 mg/l, Turbidity 1.71 - 3.84 NTU, Biochemical Oxygen Demand (BOD) 1.12 - 1.36 mg/l, Alkalinity 8.56 - 12.12 mg/l, Total Hardness 11.8 - 14.47 mg/l and Temperature 26.1℃ - 27.3℃. Analysis of cations shows that Na ranged from 7.38 - 10.34 mg/l, K 0.26 - 0.49 mg/l, Calcium ion levels 2.56 - 3.59 mg/l and Mg 0.88 mg/l - 1.23 mg/l. The anions showed Potassium ion levels ranged from 0.01 mg/l - 0.02 mg/l, Chloride ion levels 12.29 mg/l - 15.88 mg/l, Fluoride ion levels 0.01 mg/l and Nitrates from 0.27 mg/l - 0.48 mg/l. Total Heterotopic Fungi population ranged from 15.26 - 48.55 Coliform Forming units/ml. The maximum permissible value of total coliforms in drinking water was exceeded. However, the Total Hydrocarbon Concentration (THC) across the groundwater sample points was less than 0.01 mg/l. The concentration of PAH and BTEX was 0.01 mg/l across the study area. The heavy metal concentrations in the groundwater samples were negligible with levels of 0.01 mg/l observed in the study area except for iron ranging from 0.20 - 0.56 mg/l levels above the WHO permissible limit. The physico-chemical parameters of groundwater indicate that they fall below WHO permissible limits. The cations and anions concentration indicate a stable and healthy water system which is relatively good. The groundwater system has high levels of iron in groundwater and bacterial contamination. Treatment is required to avoid acute and chronic iron overload resulting from consumption f

关键词： Groundwater Physico-Chemical Parameters Oil Spill Contamination

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Distribution of Selected Toxic Elements in Water Phases of River Ogbere, Ibadan, Nigeria

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Journal of Environmental Protection 2021年第7期12卷 429-437页

作者： Chibueze godwin Achi Ayodetimi Moyin Omoniyi Akinwale Oladotun Coker Department of Civil Engineering Faculty of Technology University of Ibadan Ibadan Nigeria

Rivers in Nigeria are faced with increasing contamination of both solid and liquid wastes that enter the surrounding water bodies, and some of these are toxic pollutants that settle onto the riverbed (the ultimate sink of contaminants in the aquatic environment). These toxic pollutants are released into the aquatic environments and inadvertently pose serious public health risks and hazards. This study aims to assess the level of potentially toxic element in River Ogbere water in the city of Ibadan. A total of 12 surface water samples collected from River Ogbere in Ibadan during the dry and wet season of 2019 was analysed for pH, EC, Iron (Fe), Manganese (Mn), Zinc (Zn), Copper (Cu), Cadmium (Cd), Chromium (Cr), Lead (Pb) and Nickel (Ni). The pH was found in the alkaline range (7.40 - 7.83) while the conductance was obtained in the range of 236.67 - 353.3 μs/cm in both seasons. Fe, Mn, Zn, Cu, Cr, Pb, and Ni were detected in all the samples in the range 0.10 - 5.44 mg/L, 3.20 - 5.03 mg/L, 0.12 - 1.27 mg/L, 0.03 - 0.51 mg/L, 0.03 - 0.68 mg/L, 0.01 - 0.75 mg/L and 0.01 - 0.03 mg/L in both seasons respectively, whereas Cd was detected only in 75% of the samples (0.00 - 0.07 mg/L). Overall seasonal variation was significant for Fe, Mn, Pb, Cd, and Cr. The maximum mean concentration of Fe (5.44 mg/L), Mn (5.03 mg/L), Zn (1.27 mg/L), Cu (0.68 mg/L), Pb (0.75 mg/L) and Ni (0.03 mg/L) were all observed during the dry season. The heavy metals also varied with the change of sampling locations. The dominance of these toxic element in the surface water of River Ogbere followed the sequence: Mn > Fe > Zn > Cu > Cr > Pb > Ni > Cd. The anthropogenic activities around the study area were observed to have increased the influx of toxic metals at both upstream and downstream sections of the river. In view of the high human activities along the river, River Ogbere appeared to have been polluted visibly. The constant water quality monitoring and development of River Ogbere safety plans i

关键词： River Water Quality Pollution Toxic Metals Anthropogenic Activities Water Quality

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Post Impact of Hydrocarbon Spillage on Physicochemical Parameters and Heavy Metals in the Santa Barbara River, Nembe, Bayelsa State

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International Journal of Geosciences 2023年第10期14卷 935-954页

作者： Amararu Onyema Isukul godwin Jeremiah Udom Richmond Uwanemesor Ideozu Institute of Natural Resources Environment & Sustainable Development (INRES) Port Harcourt Nigeria Department of Geology Faculty of Science University of Port Harcourt Rivers State Nigeria

The work of the paper focused on the post impact of oil spill contamination of groundwater in Bassambiri Nembe Bayelsa State. Groundwater samples were sampled from hand dug wells from eight stations including the control point for physico-chemical investigation using sterilized glass bottles. Sampling was carried out upstream and downstream on the Santa Barbara River across the stations and the results are as follows surface water pH ranged 6.90 - 7.50, electrical conductivity 19739.41 μS/cm - 28920.64 μS/cm and Chloride 6019.63 - 9274.82 mg/l. The Total Dissolved Solids (TDS) varied from 10472.72 mg/l - 16538.19 mg/l dissolved oxygen (DO) 6.21 mg/l - 7.371 mg/l while the mean biochemical oxygen demand (BOD) 0.09 ± 0.52 mg/l - 2.4 ± 0.81 mg/l, temperature 28.04℃ - 31.79℃ while total alkalinity is 43.95 mg/L -73.87 mg/L. Calcium ion ranged 375.68 mg/l - 536.72 mg/l, Magnesium ion 88.35 - 243.24 mg/l and Potassium ion 41.27 - 121.17 mg/l. The results of the study showed that the pH, salinity, alkalinity, total suspended solids (TSS), Chlorides, Phosphates, and Nitrates are within permissible limits of the WHO, however the electrical conductivity, TDS, turbidity, DO, BOD, and hardness exceeded WHO permissible limits for drinking water. Total Petroleum Hydrocarbon (TPH) and Heavy metals had low concentrations in the Santa Barbara River across the study area suggesting that surface water is not polluted. However, the surfactants used initially to contain the oil pollution were effective based on this research.

关键词： Post Impact Oil Spillage Physiochemical Parameters Santa Barbara

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Secondary malignancy estimation in patients after mastectomy and adjuvant therapy

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Journal of Cancer Metastasis and Treatment 2018年第1期4卷 620-627页

作者： Oludare Folajimi Adeyemi Okhuomaruyi David Osahon Enosakhare godwin Okungbowa Radiotherapy and Clinical Oncology University of Benin Teaching HospitalBenin City 234Nigeria Department of Physics University of BeninBenin City 234Nigeria Department of Radiography and Radiation Science University of BeninBenin City 234Nigeria

Aim:Secondary malignancy estimation after radiotherapy of post mastectomy patients is becoming an important subject for comparative treatment *** data from modern treatment planning systems provide accurate three-dimensional dose distributions for each individual patients,thereby opening up new possibilities for more precise estimates of secondary cancer incidence rates in the irradiated ***:This study estimates the probability of secondary malignancy using radiobiological model for post mastectomy patients in a low-resource center,*** secondary cancer complication probability(SCCP)was computed for linear,linear-exponent and linear-plateau ***:The result shows that comparing the three models the mean SCCP for the contralateral breast ranged between 0.41%-0.93%;for the lung(0.34%-5.93%);while for the chest wall is between 0.65%-31.95%.Also,the result showed that based on the differential dose volume histogram,the SCCP in the chest wall is highest compared to the lung and contralateral breast;while the linear model overestimate the risk of secondary malignancy,the linear-exponent and the linear plateaus gave values not outrageously ***:The models in this study have shown that the risk of secondary malignancy in these post mastectomy patients is low.

关键词： Probability radiobiological model complication malignancy

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水稻合系41农杆菌介导转化体系的建立

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西南农业大学学报（自然科学版） 2003年第1期25卷 41-44,51页

作者：段承俐萧凤回 Carl Ruthus Ian godwin 云南农业大学农学与生物技术学院云南昆明650201 School of Land and Food the University of Queensland

研究建立了以云南水稻栽培粳稻良种合系41为主要目标的高效农杆菌介导转化体系,并获得28株转基因植株,转化率高达27.2%。GUS组织化学检测和分子生物学鉴定的结果提供了转化成功的有力证据。

关键词：水稻合系41 农杆菌介导转化体系转化率

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Using Morphological Markers to Assess Variations between and within Cultivated and Non-cultivated Provenances of Moringa Oleifera Lam. in Tanzania

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Journal of Life Sciences 2011年第5期5卷 387-392页

作者： Mariam godwin Mgendi Agnes Morris Nyomora Mkabwa Katambo Manoko Department of Biological Sciences College of Education Dares Salaam University Dares Salaam P.O BOX2329 Tanzania Department of Botany University of Dar es Salaam Dares Salaam P. 0 BOX35060 Tanzania

The use of morphological markers to assess variations between and within cultivated and non-cultivated provenances of Moringa oleifera Lam. from selected coastal regions of Tanzania was studied. A descriptors list of 15 selected morphological characters was used to generate a character state matrix. Cluster analysis using NTSYS-pc and UPGMA program produced six clusters with similarity ranging from 66% to 100%. The majority cultivated and non-cultivated clusters with similarity ranging from 86-100% and 97-100% respectively reflected a clustering pattern based on the status of individuals whether cultivated or non-cultivated. Most individuals from same population clustered differently indicating high morphological variations within populations than between populations. The present results suggest that selection and conservation of elite germplasm could be achieved by considering individuals from both cultivated and non-cultivated plants.

关键词： Morphological variations Moringa oleifera cultivated and non-cultivated NTSYS.

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Sympathetic dysfunction as a cause for hypotension in dengue shock syndrome

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Chinese Medical Journal 2012年第20期125卷 3757-3758页

作者： Jeevagan Vijayabala Malith Attapaththu Priyankara Jayawardena garath Gamini de Silva godwin Constantine University Medical Unit National Hospital of Sri Lanka Sri Lanka Asiri Hospital Colombo Sri Lanka

Dengue is an important mosquito-borne disease, caused by one of the four serotypes of dengue *** to the reports from the World Health Organization, every year 50 to 100 million infections occur, including 500 000 dengue hemorrhagic fever cases and 22 000 deaths, mostly among children.1 The main features of severe infection are hypotension, fluid leak and shock. Management of dengue shock syndrome and its pathophysiology are not fully understood. We reported two patients with dengue who developed hypotension without considerable fluid accumulation in the third space and explaining an alternative cause for hypotension in these patients.

关键词： dengue shock syndrome," hypotension sympathetic dysfunction

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Prevalence and Associated Risk Factors of Uropathogenic Klebsiella Species in Port Harcourt

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Advances in Infectious Diseases 2023年第2期13卷 333-353页

作者： Moore Ikechi Mike-Ogburia Tombari Pius Monsi Easter godwin Nwokah Department of Medical Laboratory Science Rivers State University Port Harcourt Nigeria

Background: Urinary tract infection (UTI) is a severe public health issue that affects a wide range of people around the world with Klebsiella pneumoniae accounting for up to 25% of all urinary tract infections. The higher rate of UTI associated with uropathogenic Klebsiella species has been associated with the emergence of hypervirulent and antibiotic-resistant strains facilitated by the misuse and overuse of antibiotics as well as other sociodemographic and behavioural practices of susceptible individuals. This study was aimed at investigating the prevalence and associated risk factors of uropathogenic Klebsiella species in Port Harcourt, Nigeria. Methodology: The study employed a descriptive cross-sectional study design comprising 300 subjects clinically suspected of having urinary tract infections attending the Rivers State University Medical Centre and the Rivers State University Teaching Hospital between March to August 2022. A standard urine culture procedure was used to ascertain significant bacteriuria after which Klebsiella colonies were isolated and identified using standard bacteriological techniques. The data generated from this study was represented as frequency and percentages, and inferential statistics were carried out using Chi-square with the aid of GraphPad Prism Software Version 9. Statistical significance was defined as a p-value of less than 0.05 at a 95% confidence interval. Result: The prevalence of uropathogenic Klebsiella sp. was 16%, with sex, pregnancy status, and religion of the individuals substantially linked (p p Klebsiella species. Conclusion: This study reports a relatively high prevalence of uropathogenic Klebsiella species at 16%, with the sex and pregnancy status of the subjects being significantly associated (p Klebsiella species in the current study. Health promotion and awareness efforts should be prioritised to inform susceptible demographics about their risks for urinary tract infections associated with uropathogenic Klebsi

关键词： Uropathogenic UTI Klebsiella Prevalence Risk Factors

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