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Journal of Palaeogeography 2022年第4期11卷 618-628页

作者： J.A.Adeoye V.o.Jolayemi s.o.Akande Department of Geology and Mining Ibrahim Badamasi Babangida UniversityLapai 911101Niger StateNigeria Department of Geology and Mineral sciences University of IlorinIlorin 240101Kwara StateNigeria

sedimentological and foraminiferal paleoecological studies were carried out for the oligocene-Miocene ogwashi-Asaba Formation of the Anambra Basin at the Issele-Uku area in southern Nigeria,to reconstruct *** pattern of rock successions and textural characteristics suggest the prevalence of fluvio-deltaic setting during the formation of lignites and clastic rocks of ogwashi-Asaba *** benthic foraminiferal species such as Ammotium sp.,Textularia sp.,Gavelinella sp.,Milliamina sp.,Reophax sp.,Bolivina sp.,Eponides sp.,Pseudobolivina *** Lenticulina *** the shale units whereas the planktonic forms are *** these species have very low population and diversity in the shales,which could be due to the presence of harsh conditions such as low oxygen level and scarcity of food,leading to poor *** assessments of benthic foraminifera's habitat suggest middle-to-inner neritic marine environment for the *** results suggest fluvial environment for the sandstone and deltaic for the *** ogwashi-Asaba Formation in Issele-Uku area of Anambra Basin,southern Nigeria,therefore,have records of shallow marine,and fluvio-deltaic paleoenvironments.

关键词： Foraminiferal sedimentology ogwashi-Asaba Formation Anambra Basin Paleoecology

Effect of reverse flotation on magnetic separation concentrates

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International Journal of Minerals,Metallurgy and Materials 2012年第8期19卷 669-674页

作者： s.o. Bada A.s. Afolabi M.J. Makhula school of Chemical & Metallurgical Engineering University of the Witwatersrand P/Bag X3 Wits 2050 Johannesburg South Africa Department of Mineral Processing Division Mintek Johannesburg South Africa Department of Civil and Chemical Engineering College of Science Engineering and Technology University of South Africa P/Bag X6 Florida 1710 Johannesburg South Africa

Reverse flotation studies on magnetite samples have revealed that the use of starch as a depressant of Fe-oxides has a hydrophilic effect on the surface of Fe-bearing silicates and significantly decreases Fe in the silica-rich stream when used in combination with an amine （Lilaflot D817M）. In this study, the effect of reverse flotation on the optimization of products obtained fi＇om magnetic separation was inves- tigated. Two different magnetic samples, zones 1 and 2, were milled to 〈75 btm and then subjected to low intensity magnetic separation （LIMs）. The LIMs test conducted on the 〈75 ~m shown an upgrade of 46.40wt% Fe, 28.40wt% sio2 and 2.61wt% Mno for zone 1 and 47.60wt% Fe, 29.17wt% sio2 and 0.50wt% Mno for zone 2. Further milling of the ore to 〈25 ~tm resulted in a higher magnetic-rich product after magnetic separation. Reverse flotation tests were conducted on the agitated magnetic concentrate feed, and the result shows a significant upgrade of Fe compared to that obtained from the non-agitated feed. Iron concentrations greater than 69%, and sio2 concentrations less than 2% with overall magnetite recoveries greater than 67% and 71% were obtained for zones 1 and 2, respectively.

关键词： magnetite flotation magnetic separation starch amines

Microwave assisted synthesis,spectroscopy and biochemical aspects of lanthanum(Ⅲ) and praseodymium(Ⅲ) complexes with oxadiazole functionalised dithiocarbazinates

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Journal of Rare Earths 2009年第5期27卷 698-704页

作者： shweta singh o P Pandey s K sengupta Department of Chemistry D.D.U.Gorakhpur University Chemistry Department University of Surrey

The new lanthanum (Ⅲ) and praseodymium (Ⅲ) complexes of the general formula [Ln(L)3] (Ln=La(Ⅲ) or Pr(Ⅲ); LK=potassium salt of dithiocarbazinates) were prepared by both, conventional thermal and by the use of microwave technology. Elemental analyses, electrical conductance, magnetic moment and electronic, infrared, far-infrared, 1H and 13C NMR spectral studies were used to characterize the complexes. The molecular weights of few complexes were determined by FAB-mass spectra. Nephelauxetic ratio, covalency parameter and bonding parameter for these complexes were also calculated. The probable structures of the complexes were proposed. The antifungal and antibacterial activities of the complexes were evaluated. The activities were correlated with the structures of the compounds.

关键词： lanthanum (Ⅲ) praseodymium (Ⅲ) dithiocarbazinates microwave synthesis structures antifungal antibacterial rare earths

Thermodynamic second law analysis of magneto-micropolar fluid flow past nonlinear porous media with non-uniform heat source

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Propulsion and Power Research 2020年第3期9卷 281-288页

作者： E.o.Fatunmbi s.o.salawu Department of Mathematics and statistics Federal PolytechnicIlaroNigeria Department of Mathematics Landmark UniversityOmu-AranNigeria

This study analyzes the second law of thermodynamic for entropy generation in an irreversible hydromagneto-micropolar flow system with non-homogenous heat *** non-symmetric microstructure fluid flow past a stretching sheet with saturated porous nonlinear media under magnetic field *** the fluid particle deformation,the microstructure is assumed rigid with the viscous suspended *** reduced dimensionless nonlinear formulated model is computationally coded and solved to obtain solutions for the entropy volumetric production,Bejan number and heat transfer magneto-micropolar *** parameter dependent solutions for the flow characteristics and irreversibility processes are plotted and *** is revealed from the study that minimization of entropy generation in a magneto-micropolar flow system is possible by improving the thermodynamic equilibrium with low material variables,viscosity and hysteresis ***,it is seen that the terms that encourage internal heat generation reduces the micropolar fluid viscosity in the system.

关键词： Micropolar Non-Newtonian fluid Entropy generation stretching sheet Thermodynamic law

Toward a Real-Time Framework in Cloudlet-Based Architecture

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Tsinghua science and Technology 2016年第1期21卷 80-88页

作者： o.Kotevska A.Lbath s.Bouzefrane CNRs LIGUniversity Grenoble Alpes CEDRIC Lab Conservatoire National des Arts et Metiers CNAM

In this study, we present a framework based on a prediction model that facilitates user access to a number of services in a smart living environment. Users must be able to access all available services continuously equipped with mobile devices or smart objects without being impacted by technical constraints such as performance or memory issues, regardless of their physical location and mobility. To achieve this goal, we propose the use of cloudlet-based architecture that serves as distributed cloud resources with specific ranges of influence and a realtime processing framework that tracks events and preferences of the end consumers, predicts their requirements,and recommends services to optimize resource utilization and service response time.

关键词： smart city cloudlet prediction recommendations framework real-time

Adaptive and Predictive Control strategies for Wind Turbine systems: A survey

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IEEE/CAA Journal of Automatica sinica 2019年第2期6卷 364-378页

作者： Magdi s.Mahmoud Mojeed o.oyedeji the systems Engineering Department King Fahd University of Petroleum and Minerals (KFUPM)

The wind turbine(WT) is a renewable energy conversion device for transformation of kinetic energy from the wind to mechanical energy for subsequent use in different *** paper focuses on wind turbine control design *** content is divided into the following parts: 1) An overview of the recent advances that have been made in the application of adaptive and model predictive control strategies for wind turbines. 2) summarizes some important aspects of modeling of wind turbines for control studies. 3) Provides an outlook on the application of adaptive model predictive control for uncertain systems to stimulate new research interests for wind turbine systems. We provide an overall picture of the research results with evaluation of the merits/demerits.

关键词： Adaptive control model predictive control wind turbine(WT)

Recent advances in sturgeon nutrition

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Animal Nutrition 2017年第3期3卷 191-204页

作者： silas s.o.Hung Department of Animal science University of California

sturgeons are fish species of biological and economical importance, and most of them are endangered,vulnerable or rare because of their large size, late sexual maturity, long period between spawning, and longevity. These unique biological characteristics make them highly susceptible to overfishing, degradation of habitat and spawning ground, and contamination of water and sediments by pollutants. The objective of the current review is not to exhaustively include all studies on sturgeon nutrient requirements and utilizations conducted under laboratory conditions, but to critique some studies and update previous reviews. The goal is to provide a basis for recommendations for future research so that these important fish species can be managed and produced sustainably. Energy, protein, lipid carbohydrate, vitamin, and mineral requirements and utilizations were reviewed or critiqued. Future studies to develop suitable chemically defined diets to support good growth of sturgeon are urgently ***, future experiments should be designed systematically with more consideration on within and among studies and within and among different species of sturgeon. Finally, future experiments should be designed with a systematic approach with multiple doses(inputs) and multiple responses(outputs) at several levels of hierarchical organization in a biological system using traditional biochemical and modern molecular techniques and computer modeling with proper experimental design and methodology. This approach will provide a more realistic and holistic understanding of the mechanisms of nutrient requirements and utilizations, which will help us better manage wild sturgeon stocks and produce sturgeon more efficiently and sustainably under aquaculture conditions.

关键词： sturgeon Nutrition Energy Protein Lipid Carbohydrate

Effect of piospheres on physio-chemical soil properties in the southern Rangelands of Kenya

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Ecological Processes 2017年第1期6卷 142-148页

作者： s.o.Jawuoro o.K.Koech G.N.Karuku J.s.Mbau Department of Land Resource Management and Agricultural Technology(LARMAT) University of NairobiP.O.Box 29053-00625NairobiKenya

Introduction:Water-based interventions haphazardly introduced in the drylands of Kenya have led to the introduction of piospheres used as concentration *** much is known about the effect of these piospheres on soil physio-chemical properties,especially in the Kenyan rangelands where the government and other development agencies have created piospheres aimed at curbing water shortages and sustaining livestock *** study assessed the effect of piospheres on soil physio-chemical characteristics in the southern rangelands of Kajiado,Kenya,in order to provide evidence-based insights that will be useful in guiding future water ***:soil samples were collected within 0.25-m2 plots at 20-m intervals along 100-m transects from three piospheres(a dam,a trough,and a seasonal river).Two-way ANoVA was used to determine if there were significant differences in soil parameters between piospheric ***:soil bulk density significantly different between piospheric distances(F=22.25,P=0.001)and piospheres(F=13.10,P=0.002),being highest at 20 m from the trough(1.1–1.21 gcm−3)relative to a similar distance from the dam(1.01–1.20 gcm−3)and the river(1.1–1.17 gcm−3).on the other hand,mean soil aggregate stability significantly increased(F=66.89,P=0.001)with piospheric distance,being lowest at 20 m from the trough(43.9–46.2%),the dam(43.1–48.9%),and the river(46.6–47.5%).Conclusions:High soil bulk density and consequent low soil porosity,hydraulic conductivity,and moisture content demonstrated that grazing was high near the *** is recommended that livestock should be herded away from the piospheres after drinking water to ensure that grazing livestock spend less time near the piospheres if reduced soil compaction is to be *** should also be better planned and placed at landscape level to exploit landscape heterogeneity.

关键词： Piospheres Grazing pressure Bulk density Hydraulic conductivity Rangelands

Plant species composition and diversity depending on piospheres and seasonality in the southern rangelands of Kenya

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Ecological Processes 2017年第1期6卷 159-167页

作者： s.o.Jawuoro o.K.Koech G.N.Karuku J.s.Mbau Department of Land Resource Management and Agricultural Technology(LARMAT) University of NairobiP.O.Box 29053-00625NairobiKenya

Introduction:scarcity of water in the rangelands of Kenya has led to the introduction of *** research has however produced contrasting results on the effects of piospheres and seasonality on shannonWiener’s diversity index,and therefore,this information is still *** this study,the impact of these piospheres on plant species composition,diversity,and richness was ***:Vegetation sampling was done during both the long rains(April)and the dry season(August).Three piosphere types(dam,trough,and a seasonal river)were studied using 0.25 m2 quadrats to sample vegetation at intervals of 20 m along 100-m *** 100-m transects were used per piosphere(north,east,south,and west directions).shannon-Wiener’s diversity index was used to determine species richness and ***way ANoVA was used to determine if piospheric distance had an effect on species diversity,richness,and evenness using Genstat 15th ***:A total of 22 grasses and 29 forbs were recorded in the study *** most abundant grasses near the piospheres were Eragrostis tenuifolia(12.9%)and Cynodon dactylon(10.6%).*** is an increaser species and was therefore most abundant in areas of severe grazing while *** has been known to be tolerant to *** most abundant forbs were Crotalaria brevidens(37.5%).The shannon-Wiener diversity index significantly increased(F=25.07,P=0.001)with distance from the three piospheres owing to the high grazing intensity near the piospheres and was significantly different between piospheres,being higher(F=10.05,P=0.001)at 20 m from the river(1.2±0.1)compared to a similar distance from the dam(0.9±0.1)and the trough(0.8±0.2).This was probably because the trough was smaller in size compared to the other piospheres,thereby concentrating more grazing animals per unit area and causing a greater impact on plant ***:The study demonstrated that species diversity,richness,and evenness were low ne

关键词： Piosphere species composition shannon-Wiener diversity species richness Rangelands

Utilizing short Tandem Repeats (sTRs) as a Resolving Matrix in Parental Dispute DNA Analysis

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American Journal of Molecular Biology 2018年第3期8卷 156-165页

作者： George Gborienemi simeon alade Tolulope olukemi Department of Medical Laboratory science Niger Delta University Amassoma Nigeria

Interest in DNA analysis using short tandem repeats (sTR) as finger printing tools in forensic medicine has gained tremendous application, as expression of these nuclear factors have enhanced forensic examination. Here we used this Biochemical characterization after conventional extraction process, polymerase chain reaction (PCR), gel electrophoresiss and a sequencer to distinguish and resolve parental dispute. The differential migration of labeled DNA fragments which attains excitation energy with a laser elicits fluorescent light of different wavelength depending on the dye used. A data collection software (Genemapper) collects raw data (spectrograph) and converts it to an electropherogram that is interpreted. By comparing the DNA profiles, inclusion and exclusion criteria were elucidated to resolve disputes. The inherent discriminating power of sTRs used in analysis enhances resolution of cell mixtures, genetic aberration, substantiation of tissue origin and provides genetic distinction which is a robust and reliable approach in resolving parental disputes.

关键词： short Tandem Repeats Matrix Parental DNA Analysis