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Source, Contamination Assessment and Risk Evaluation of Heavy Metals in the Stream Sediments of Rivers around Olode Area SW, Nigeria

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Journal of Environmental & Earth Sciences 2023年第1期5卷 65-84页

作者： Stellamaris Isioma Okonkwo Sunday Ojochogwu Idakwo Mofolorunsho Samuel Kolawole olufemi faloye Anthony Azubuike Elueze Department of Geology Federal University of TechnologyOwerriOwerriImo State460114Nigeria Department of Geology and Mining Ibrahim Badamasi Babangida UniversityLapaiNiger State740005Nigeria Department of Geology Federal UniversityOye-EkitiEkiti State360001Nigeria Department of Geology University of IbadanIbadan200005Nigeria

In order to investigate the source,contamination,and risk of heavy metals such as Pb,Zn,Cu,Ni,Co,Fe,Mn,and Cr,twelve(12)stream sediments and ten(10)rock samples were collected from pegmatite mining sites at Olode and its environs inside Ibadan,Southwestern *** average values and order of abundance obtained followed the pattern:Mn(595.09)>Ba(80)>Cr(50.82)>V(45.09)>Zn(29.73)>Cu(13.82)>Co(13.82)>Sr(10.46)>Ni(9.73)>Pb(9.09)>Fe(1.59).These were greater than the background values,indicating that mining has a negative impact on the study area,as indicated by the high coefficient of variation and correlation values(>0.6)for Copper-Lead(0.929),Copper-Vanadium(0.970),Copper-Chromium(0.815),Lead-Vanadium(0.884),and *** the basis of the enrichment factor(EF),the Olode sediments show extremely high enrichment for Mn and Ba in the research *** and Ni are most likely to blame for the elevated contamination levels,according to CF *** degree of contamination(CD),pollution load index(PLI),pollution index(PI),and modified pollution index(MPI)all revealed high levels of contamination in all stream sediment samples,whereas Igeo shows that the Olode stream sediments are“practically uncontaminated to extremely contaminated by Ni,Co,and Mn”.Ni and Cu are the major regulating factors that are most likely causing the possible *** a result,these findings give important information for conducting appropriate ecological management research.

关键词： Olode Heavy metals Stream sediments Risk assessment Contamination indices

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Yield and mechanical properties of veneer from Brachystegia nigerica

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Journal of Forestry Research 2012年第2期23卷 295-298页

作者： Babatola olufemi Department of Forestry and Wood Technology Federal University of TechnologyP.M.B.704AkureNigeria

In an effort to find suitable wood from natural forest to meet the demand for veneer products, the yield and tensile strength of veneers produced from Brachystegia nigerica were investigated. Two trees of B. nigerica were separately selected from 10 different natural forest zones while two logs were obtained from each tree. The logs were debarked and steamed in a vat prior to rotary peeling and slicing for veneer production. The optimum steam temperature was determined by considering different temperatures： 50℃, 60℃, 70℃, 80℃ and 90℃ for 24 h. Thereafter, optimum steam time was determined at the optimum temperature by considering durations of 24, 48, 72 and 96 h. The average taper of 0.75 mm per 1.0 m length was recorded for B. nigerica, indicating that the logs were reasonably cylindrical; thereby its logs are good for the production of veneer. The yield ranged from 44% to 61% with an average of 52% of the log input. The tensile strength of the veneer was tested perpendicular to grain and both peeled and sliced veneers had the highest tensile strength between 70℃ and 90℃, suggesting that softening of wood polymers, especially lignin, is between 70℃ and 90℃. The optimum temperature and time for veneer production are 70℃ and 48 h, respectively. Commercial production of veneer from B. nigerica is feasible based on the yield and mechanical properties of the obtained veneer, thereby encouraging the expansion of the scope of its utilization.

关键词： veneer Brachystegia nigerica yield tensile strength optimum steam temperature optimum steam time

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固相流动对垂直气井井筒压降影响的数值模拟(英文)

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石油勘探与开发 2012年第2期39卷 228-232页

作者： Adekomaya olufemi A 尼日利亚拉各斯大学石油与天然气工程学院

为了准确估算垂直气井井底压力,更精确地预测单井产量,在总结前人有关垂直井筒单相管流井筒压降计算方法的基础上,建立了固相流动对垂直气井井筒压降影响的数值模型。该模型考虑了直井中气相湍流、固相颗粒流动及Moody摩擦系数对井筒压... 详细信息

为了准确估算垂直气井井底压力,更精确地预测单井产量,在总结前人有关垂直井筒单相管流井筒压降计算方法的基础上,建立了固相流动对垂直气井井筒压降影响的数值模型。该模型考虑了直井中气相湍流、固相颗粒流动及Moody摩擦系数对井筒压降的影响,扩展了Adekomaya等(2011年)及Sukkar&Cornell提出的单相垂直管流井筒压降计算方法。模型计算结果表明,固相流动对井筒压降影响显著,而前人提出的计算模型未能考虑其影响;相同条件下,当有固相颗粒伴随流体产出时,井筒压降高于无固相颗粒产出时的井筒压降;固相含量越高、固相相对密度越大,井筒压降越大,压力随深度的增加降低越快。

关键词：井底压力固体流压降浊流垂直井

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Geothermo-mechanical alterations due to heat energy extraction in enhanced geothermal systems: Overview and prospective directions

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Deep Underground Science and Engineering 2024年第3期3卷 256-268页

作者： Mary C.Ngoma Oladoyin Kolawole olufemi Olorode John A.Reif Jr.Department of Civil and Environmental EngineeringNew Jersey Institute of TechnologyNewarkUSA Department of Petroleum Engineering Louisiana State UniversityBaton RougeUSA

Geothermal energy from deep underground (or geological) formations,with or without its combination with carbon capture and storage (CCS),can be a key technology to mitigate anthropogenic greenhouse gas emissions and meet the 2050 net‐zero carbon emission *** resources in low‐permeability and medium‐and high‐temperature reservoirs in sedimentary sequence require hydraulic stimulation for enhanced geothermal systems (EGS).However,fluid migration for geothermal energy in EGS or with potential CO_(2) storage in a CO_(2)‐EGS are both dependent on the in situ flow pathway network created by induced fluid *** thermo‐mechanical interactions can be complex and induce varying alterations in the mechanical response when the working fluid is water (in EGS) or supercritical CO_(2)(in CO_(2)‐EGS),which could impact the geothermal energy recovery from geological ***,there is a need for a deeper understanding of the heat extraction process in EGS and CO_(2)‐*** study presents a systematic review of the effects of changes in mechanical properties and behavior of deep underground rocks on the induced flow pathway and heat recovery in EGS reservoirs with or without CO_(2) storage in CO_(2) ‐***,we proposed waterless‐stimulated EGS as an alternative approach to improve heat energy extraction in ***,based on the results of our literature review and proposed ideas,we recommend promising areas of investigation that may provide more insights into understanding geothermo‐mechanics to further stimulate new research studies and accelerate the development of geothermal energy as a viable clean energy technology.

关键词： CO_(2)-EGS enhanced geothermal systems geomechanics geothermal energy underground thermal energy

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Analyzing thermal maturity effect on shale organic matter via PeakForce quantitative nanomechanical mapping

Rock Mechanics Bulletin

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Rock Mechanics Bulletin 2024年第3期3卷 38-52页

作者： Chioma Onwumelu Oladoyin Kolawole Stephan Nordeng olufemi Olorode Harold Hamm School of Geology and Geological Engineering University of North DakotaGrand ForksND58202USA John A.Reif Jr.Department of Civil and Environmental EngineeringNew Jersey Institute of TechnologyNewarkNJ07102USA Craft and Hawkins Department of Petroleum Engineering Louisiana State UniversityBaton RougeLA70803USA

Organic-rich shales have gained significant attention in recent years due to their pivotal role in unconventional hydrocarbon *** shale rocks undergo thermal maturation processes that alter their mechanical properties,making their study essential for subsurface ***,characterizing the mechanical properties of organic-rich shale is often challenging due to its multiscale nature and complex *** work aims to bridge that knowledge gap to fully understand the nanomechanical properties of Shale organic matter at various thermal maturation *** study employs PeakForce Quantitative Nanomechanical Map-ping(PF-QNM)using Atomic Force Microscopy(AFM)to investigate how changes at the immature,early mature,and peak mature stages impact the mechanical properties of the Bakken Shale organic ***-QNM provides reliable mechanical measurements,allowing for the quantification and qualification of shale constituents'elastic modulus(E).We also accounted for the effect of probe type and further analyzed the impact of probe wear on the nanomechanical properties of shale organic *** immature shale,the average elastic modulus of organic matter is approximately 6 GPa,whereas in early mature and peak mature shale,it decreases to 5.5 GPa and 3.8 GPa,*** reveal a mechanical degradation with increasing thermal maturation,as evidenced by a reduction in Young's modulus(E).Specifically,the immature shale exhibits an 8%reduction in E,while the early mature and peak mature shales experience more substantial reductions of 31%and 37%,*** phenomenon could be attributed to the surface probing of low-modulus materials like bitumen generated during *** findings underscore the potential of AFM PF-QNM for assessing the nanomechanical characteristics of complex and heterogeneous rocks like ***,it also highlights the need for standardized mea-surement practices,considering the diverse components in these

关键词： Rock mechanics Nanomechanics Shale Organic matter Atomic force microscopy Nanomechanical mapping

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Toxicological and histopathological effects of Dennettia tripetala seed used as grain protectant,food,and medicine

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Food Quality and Safety 2017年第3期1卷 211-219页

作者： Luke Chinaru Nwosu Chris Olukayode Adedire Emmanuel Oludele Ogunwolu Michael olufemi Ashamo Food Technology Programme Department of BiologyFederal University of TechnologyAkureOndo State and Department of Crop and Environmental Protection University of AgricultureMakurdiBenue StateNigeria Department of Crop and Soil Science Faculty of AgricultureUniversity of Port HarcourtP.M.B.5323Port HarcourtRivers StateNigeria

The study revealed the safety of Dennettia tripetala seed on man and the *** male rats weighing 0.158-0.168 kg housed in standard cages with free access to food and water were used for the *** median lethal dose(LD50)was estimated using revised up and down *** LD50 for *** seed extract was 5785 mg/kg and this evoked paralysis in rats for 4 days coupled with discharge from the eyes and eventual *** least weight gain by the animals administered 75%seed powder of ***(4338.75 mg/kg)was an index of high powder concentration,whereas the weight loss experienced by group V animals is strongly attributed to chemical assault by permethrin designated as a standard *** high values of alanine aminotransferase(ALT),aspartate aminotransferase(AST),and urea in the groups administered 75%permethrin powder(4338.75 mg/kg)and 75%*** seed powder is an index of liver and kidney injury and *** presence of normal serum levels of ALT,AST,alkaline phosphatase,and creatinine;normal liver and kidney structures;and normal weight gains in the animal groups fed basal diet(control)and basal diet plus 25%*** is a strong indication that 25%*** seed powder(1446.25 mg/kg)supplementation is not toxic to the liver and kidney and therefore supports normal organ *** LD50 recorded strongly indicates that *** has a moderately high safety *** of less than 50%(2892.5 mg/kg)is recommended in the safe use of the plant material as grain protectant,food,and *** botanical insecticide,***,is safer than the conventional synthetic insecticide,permethrin,on account of the latter showing evidence of kidney damage.

关键词： Safety botanical insecticide permethrin supplementation kidney damage

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Spontaneous pneumothorax in a single lung transplant recipient-a blessing in disguise: A case report

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World Journal of Clinical Cases 2020年第14期8卷 3031-3038页

作者： Himanshu Deshwal Subha Ghosh Kathleen Hogan olufemi Akindipe Charles Randall Lane Atul C Mehta Division of Pulmonary Critical Care and Sleep MedicineNew York University Grossman School of MedicineNew YorkNY 10016United States Imaging Institute Section of Thoracic ImagingCleveland ClinicClevelandOH 44195United States Respiratory Institute Cleveland ClinicClevelandOH 44195United States

BACKGROUND End-stage chronic obstructive pulmonary disease(COPD)is one of the common lung diseases referred for lung *** to the international society of heart and lung transplantation,30%of all lung transplantations are carried out for COPD *** compared to bilateral lung transplant,singlelung transplant(SLT)has similar short-term and medium-term results for *** patients with severe upper lobe predominant emphysema,lung volume reduction surgery is an excellent alternative which results in improvement in functional status and long-term *** 2018,endobronchial valves were approved by the Food and Drug Administration for severe upper lobe predominant emphysema as they demonstrated improvement in lung function,exercise capacity,and quality of ***,the role of endobronchial valves in native lung emphysema in SLT patients has not been *** SUMMARY We describe an unusual case of severe emphysema who underwent a successful SLT 15 years ago and had gradual worsening of lung function suggestive of chronic lung allograft ***,her lung function improved significantly after a spontaneous pneumothorax of the native lung resulting in auto-deflation of large *** This case highlights the clinical significance of native lung hyperinflation in single lung transplant recipient and how spontaneous decompression due to pneumothorax led to clinical improvement in our patient.

关键词： Native lung hyperinflation Single lung transplant Pneumothorax Bronchoscopic lung volume reduction Endobronchial valve Case report

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Burden of disability in type 2 diabetes mellitus and the moderating effects of physical activity

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World Journal of Clinical Cases 2023年第14期11卷 3128-3139页

作者： olufemi O Oyewole Ayotunde O Ale Michael O Ogunlana Thavanesi Gurayah Department of Physiotherapy Olabisi Onabanjo University Teaching HospitalSagamu 201101OgunNigeria College of Health Sciences University of KwaZulu-NatalDurban 3629South Africa Department of Medicine Olabisi Onabanjo UniversitySagamu 121101OgunNigeria Department of Endocrinology Diabetes and Metabolism UnitMedicineOlabisi Onabanjo University Teaching HospitalSagamu 121101OgunNigeria Department of Physiotherapy Federal Medical CentreAbeokuta 110101OgunNigeria Occupational Therapy School of Health SciencesUniversity of Kwazulu NatalPrivate Bag X54001Durban4000

The growing diabetic epidemic has created a substantial burden,not only on the people with diabetes but also on society at *** mini-review discussed the limitations and patterns of disability in type 2 diabetes mellitus and put forward a case for the moderating effects of physical activity(PA)in the management of *** limitations and impairments associated with diabetes include vascular,neurological,cardiac,and renal ***,individuals participate less in their daily lives and in their instrumental activities of daily living,which negatively impacts the quality of life of individuals with *** often leads to a loss of quality of life due to disabilities,resulting in an increased rate of disability-adjusted life years among people with type 2 diabetes ***,there are psychosocial sequelae of diabetes *** necessitates looking for moderating factors that may reduce the burden of the *** has been shown to be one of the factors that can mitigate these *** does this in several ways,including through the benefits it confers,such as a reduction of hemoglobin A1c,a reduction of excess fat in the liver and pancreas,and the reduction of cardiovascular risk factors,all of which favorably affect glycemic ***,PA regulates or moderates diabetes disability through two mechanisms:The regulation of glucolipid metabolism disorders and the optimization of body mass index and systemic ***,efforts should be directed at PA uptake through identified *** will not only prevent diabetes or diabetes complications but will reduce its burden.

关键词： Type 2 diabetes mellitus Disability burden Physical activity Moderating effect

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Identification, isolation and characterization of the antifeedant constituent of Clausena anisata against Helicoverpa armigera （Lepidoptera： Noctuidae）

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Insect Science 2009年第3期16卷 247-253页

作者： olufemi O. R. Pitan O. O. Ayelaagbe Hong-Lei Wang Chen-Zhu Wang State Key Laboratory of Integrated Management of Pest insects and Rodents Institute of Zoology Chinese Academy of Sciences BeijingChina Department of Crop Protection University of Agriculture Abeokuta Department of Chemistry University of Ibadan IbadanNigeria

Hexane, petroleum ether, chloroform, ethyl acetate, methanol and water extracts of Clausena anisata [（Willd.） Hook E Ex Benth] leaves and roots were evaluated against Helicoverpa armigera （Hubner） for antifeedant activities. Antifeedant activity was confirmed, and was found to be higher in root extracts than those of the leaf. Chloroform and petroleum ether extracts of the root showed strongest antifeedant activities （DC50s [concentration （C） causing 50% deterrence compared with the control] 0.014% and 0.016% respectively）, and root extracts were fractionated using silica gel column chromatography. One fraction of the chloroform and one of the petroleum ether root extracts was active; and on the basis of mass spectroscopy and ^1H and ^13C nuclear magnetic resonance spectral data, the active compounds in the two fractions were confirmed to be identical, and identified as osthol [2H-1-Benzopyran-2-one, 7-methoxy-8-（3-methyl-2-butenyl）]. The highest concentration of osthol was found in the chloroform root extract. Antifeedant activities of the root extracts, as measured by DC50 values, were highly correlated with their osthol contents. Approximately 99% of the variation in bioactivity of the root extracts could be accounted for by variation in osthol content; osthol therefore, appeared to be an antifeedant component of C. anisata to H. armigera. This may provide a new approach to managing this pest.

关键词： active ingredient antifeedant Clausena anisata Helicoverpa armigera,osthol root

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Systematic assessment of Pichia pastoris system for optimized b -galactosidase production

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Synthetic and Systems Biotechnology 2017年第2期2卷 113-120页

作者： Hongbing Sun olufemi Emmanuel Bankefa Ijeoma Onyinyechi Ijeoma Liangtian Miao Taicheng Zhu Yin Li CAS Key Laboratory of Microbial Physiological and Metabolic Engineering Institute of MicrobiologyChinese Academy of SciencesBeijing100101China Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin300308China Department of Microbiology University of Port HarcourtPort HarcourtNigeria

*** b-Galactosidase(commonly known as b-lactase;EC 3.***.1.23)is a multifunctional enzyme that can catalyze the hydrolysis of terminal non-reducing b-D-galactose residues in b-D-galactosides or transfer the galactosyl residue to saccharide acceptors to yield galactooligosaccharides(GOS).b-Galactosidase has a variety of applications in food and medical industries such as hydrolysis of lactose in milk,manufacture of galactooligosaccharides(GOS)and treatment of lactose malabsorption[1].Although b-galactosidase is an ubiquitous enzyme existing in plants,animals and microorganisms,only a few b-galactosidases from Kluveromyces lactis,Aspergillus niger and Aspergillus oryzae are regarded as safe for food related industry applications.

关键词： hydrolysis system residue

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