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Energy Geoscience 2024年第3期5卷 244-260页

作者： vivian o.oguad.nma Jean-Yves Reynaud Vincent Delhaye-Prat Tony Akpi Scott Thackrey Ademola Lanisa Massimo Dall’Asta Univ.Lille CNRSUniv.Littoral Côte d'OpaleUMR 8187LOGLaboratoire d'Océanologie et de GéosciencesF 59000 LilleFrance Total Energies E&P Africa-HUB CSTJFAvenue Larribau64000PauFrance

High-resolution 3D seismic data analysis was integrated with a calibrated well and biostratigraphy data to present the first overview of a buried Pleistocene canyon system on the upper slope of the eastern Niger Delta,the Galabor *** maps of specific horizons allow documenting the changing morphologies and infill lithologies of two main branches of the canyon through two stages of activity separated by a reference horizon dated at 0.99 Ma based on well *** the upper slope,growth faults dissect the canyon heads,the catchment of which encroaches a network of valleys incised on the outer *** canyon fill is composed of muddy channels and mass-transport deposits,largely derived from the collapse of canyon walls and sand-rich bodies forming a tract sourced by shelf-edge deltas at the outlet of the incised ***-density turbiditic processes likely control the distribution of sand bodies along the canyon,ranging from tributary fans on the upper slope to 6 km-wide meander belts on the middle *** sandy deposits accumulate in minibasins formed along the canyon path,downstream of the subsiding hanging wall of the growth faults and upstream of shale ridges that damp the flow in the *** results show that canyons can be major targets for sand reservoir exploration on the upper slope of large muddy deltas.

关键词： Geomorphology Submarine canyon 3D seismic Fault Shale ridge Reservoir Channel

Pore pressure prediction in offshore Niger delta using data-driven approach: Implications on drilling and reservoir quality

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能源地球科学(英文) 2023年第3期4卷 252-265页

作者： Joshua Pwavodi Ibekwe N.Kelechi Perekebina Angalabiri Sharon Chioma Emeremgini vivian o.oguad.nma Univ.Grenoble Alpes Univ.Savoie Mont BlancCNRSIRDUGEISTerre38000GrenobleFrance TotalEnergies SA CSTJF Avenue Larribau64000PauFrance Centre of Excellence in Petroleum Geoscience and Engineering University of BeninBenin CityEdo StateNigeria Univ.Lille CNRSUniv.Littoral Cote d’OpaleUMR 8187LOGLaboratoire d’Oceanologie et de Geosciences59000LilleFrance

Despite exploration and production success in Niger Delta,several failed wells have been encountered due to ***,it is very essential to understand the spatial distribution of pore pressure and the generating mechanisms in order to mitigate the pitfalls that might arise during *** research provides estimates of pore pressure along three offshore wells using the Eaton's transit time method,multi-layer perceptron artificial neural network(MLP-ANN)and random forest regression(RFR)*** results show that there are three pressure magnitude regimes:normal pressure zone(hydrostatic pressure),transition pressure zone(slightly above hydrostatic pressure),and over pressured zone(significantly above hydrostatic pressure).The top of the geopressured zone(2873 mbRT or 9425.853 ft)averagely marks the onset of overpressurization with the excess pore pressure above hydrostatic pressure(P∗)varying averagely along the three wells between 1.06−24.75 *** results from the three methods are self-consistent with strong correlation between the Eaton's method and the two machine learning *** models have high accuracy of about>97%,low mean absolute percentage error(MAPEoefficient of determination(R2>0.98).our results have also shown that the principal generating mechanisms responsible for high pore pressure in the offshore Niger Delta are disequilibrium compaction,unloading(fluid expansion)and shale diagenesis.

关键词： Niger Delta Pore pressure Reservoir Fracturing pressure Artifidal neural network Machine leaming algorithm Random forest regression

Effect of age and different doses of dietary vitamin E on breast meat qualitative characteristics of finishing broilers

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Animal Nutrition 2021年第1期7卷 163-167页

作者： vivian Vieira Francielle o.Marx Lucas S.Bassi Marley C.Santos Alexandre oba Simone Gisele de oliveira Alex Maiorka Federal University of Paraná Curitiba80035-050Brazil State University of Londrina Londrina86055-900Brazil

The supplementation of vitamin E on broiler chicken diets is essential to the prevention of lipid oxidation reactions in the meat and improvement of meat *** objective of this study was to assess the effect of different doses of dietary vitamin E on breast meat quality of broiler chickens in the finishing *** doses of vitamin E were used(30,90,150,210,and 270 mg/kg feed)in broilers'diets from 42 to 54 d of age.A completely randomized design was conducted,followed by a split-plot,where the vitamin E dose was considered as the whole plot,and broilers'age at slaughter was the *** meat quality was assessed at 4 different ages(45,48,51,and 54 d old),using 50 birds per age,totaling 200 *** quality characteristics evaluated were:pH at 24 h post mortem,color(brightness,redness,and yellowness),water holding capacity,cooking loss,shear force,and lipid *** was no interaction between age and dose of vitamin E for meat quality characteristics(P>0.05).The age at slaughter had a quadratic effect(Pon pH,brightness,redness,and water holding *** pH values were higher in the breast meat of older birds(51 and 52 d old),breast meat of younger birds(48 d)had a more reddish *** force value was higher in breast meat of birds slaughtered at later ages(Poses,whereas treatments did not alter yellowness,cooking loss,and lipid *** this study,increasing vitamin E doses in the finishing period increased the brightness of broiler breast meat,whereas slaughtering at later ages resulted in greater meat pH and shear force value.

关键词： Alpha-tocopherol Broiler chicken Meat quality oxidation Vitamin

Impact of enclosure management on soil properties and microbial biomass in a restored semi-arid rangeland, Kenya

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Journal of Arid Land 2014年第5期6卷 561-570页

作者： Stephen M MUREITHI Ann VERDooDT Charles KK GACHENE Jesse T NJoKA vivian o WASoNGA Stefaan De NEVE Elizabeth MEYERHoFF Eric Van RANST Laboratory of Soil Science Department of Geology and Soil Science Ghent University Department of Land Resources Management and Agricultural Technology University of Nairobi Research Unit of Soil Degradation and Conservation Department of Soil Management Ghent University Rehabilitation of Arid Environments Trust

Rangeland degradation is a serious problem throughout sub-Saharan Africa and its restoration is a challenge for the management of arid and semi-arid areas. In Lake Baringo Basin of Kenya, communities and individual farmers are restoring indigenous vegetation inside enclosures in an effort to combat severe land degradation and address their livelihood problems. This study evaluated the impact of enclosure management on soil properties and microbial biomass, being key indicators of soil ecosystem health. Six reseeded communal enclosures using soil embankments as water-harvesting structures and strictly regulated access were selected, varying in age from 13 to 23 years. In six private enclosures, ranging from 3 to 17 years in age, individual farmers emulated the communal enclosure strategy and restored areas for their exclusive use. Significant decreases in bulk density, and increases in the soil organic carbon, total nitrogen and microbial biomass contents and stocks were found in the enclosures as compared with the degraded open rangeland. In the private enclosures, the impact of rehabilitation on the soil quality was variable, and soil quality was in general lower than that obtained under communal management. The significant increase of absolute stocks of carbon, nitrogen and microbial biomass compared to the degraded open rangeland indicates the potential for the restoration of soil quality through range rehabilitation. over-sowing with indigenous legume fodder species could improve total nitrogen content in the soil and nutritional value of the pastures as well.

关键词： rangeland degradation enclosures microbial biomass rehabilitation reseeding soil quality Kenya

Evaluation of biological effects of three neodymium compounds on silkworm,Bombyx mori

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Journal of Rare Earths 2021年第10期39卷 1289-1299,I0005页

作者： vivian Andoh Huaiyang Guan Lin Ma Weiguo Zhao Long Li Guohua Wu College of Biotechnology Jiangsu University of Science and TechnologyZhenjiang 212018China The Sericultural Research Institute Chinese Academy of Agricultural SciencesZhenjiang 212018China

Neodymium(Nd)is one of the most famous members of rare earth elements *** the increasing global demand for Nd,it can inevitably enter the environment and affect the ecological environment through the food chain and other ***,it is very important to study the biological effects of *** this study,the biological effects of 3 kinds of Nd compounds,*** oxide(Nd_(2)o_(3)),neodymium chloride(NdCl3)and neodymium nitrate(Nd(No_(3))_(3)),were evaluated by using silkworm models through the method of intravascular *** of the three Nd compounds was prepared into 6 groups at different concentrations(40,50,60,70,80,90μg/μL).The results show that within the certain concentration range,Nd compounds show great damage to the growth of silkworms since high death rate is observed:the death rate from Nd2 o3 group is floating between 30%and 80%,the one from NdCl3 group is between 17%and 33%and that from Nd(No3)3 group is between 23%and 37%.It also reveals that Nd compounds have some negative effects on the body length and weight of ***,the histophysiological study shows that the three Nd compounds cause no obvious negative effects on the cell morphologies in midgut,fat body and silk *** XRD and FTIR spectra show that the secondary and the crystalline structures of silks are not destroyed,the TGA and DTG data exhibit that the thermal stability of silks is not damaged,and the tensile test shows that the mechanical properties of silks are not affected significantly by the intake of Nd *** general,the intake of Nd compounds has significant inhibitory effects on silkworm growth but little negative impact on silk structures or cell morphology,the study can provide useful toxicological data for the safe application of Nd compounds in various fields.

关键词： Nd compounds Bombyx mori Model animal Biological effects Rare earths

Ultralong and Mesoporous Zno and γ-Al_2o_3 oriented Nanowires obtained by Template-assisted Hydrothermal Approach

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Journal of Materials Science & Technology 2014年第12期30卷 1167-1173页

作者： Carminna ottone vivian Farías Rivera Marco Fontana Katarzyna Bejtka Barbara onida Valentina Cauda Center for Space Human Robotics Polito Istituto Italiano di Tecnologia Corso Trento 21 Turin Italy Dipartimento di Scienza Applicata e Tecnologia (DISAT) Politecnico di Torino Corso Duca Degli Abruzzi 24 Turin Italy

Highly mesoporous Zn o and g-Al2o3nanowires（NWs） are both synthesized by a hydrothermal method using commercially available porous anodic aluminium oxide（AAo） as template. AAo membrane acts as template for Zn o NWs and both as template and precursor for g-Al2o3 NWs. The formation of intermediate phases of porous Zn6Al2（oH）16Co3and boehmite（g-Al ooH） were observed, both occurring during the hydrothermal synthesis of porous Zn o and g-Al2o3 NWs, respectively, and disappearing after annealing at 600 C. This novel template-assisted hydrothermal process leads to the formation of porous Zn o and g-Al2o3NWs（specific surface area of 192 m2 g 1and 263 m2 g 1, respectively）, showing pore sizes around 4 nm in diameter. The influence of the reaction parameters on the nanostructure morphology was also investigated. A Zn o seed layer, deposited on the AAo channels prior to the hydrothermal synthesis, leads to more compact Zn o nanowires（99 m2 g-1） protecting the AAo host from the chemical attack of the precursor solution.

关键词： Mesoporous Zno nanowires Mesoporous γ-Al2o3 nanowires Boehmite Template-assisted method Hydrothermal synthesis

Impacts of long-term land-use changes on herd size and mobility among pastoral households in Amboseli ecosystem,Kenya

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Ecological Processes 2018年第1期7卷 32-40页

作者： Kennedy Sakimba Kimiti David Western Judith Syombua Mbau oliver vivian Wasonga Department of Land Resource Management and Agricultural Technology University of Nairobi P.O Box 30197NairobiKenya Amboseli Conservation Project P.O Box 15289Nairobi 00509Kenya

Introduction:Long-term changes in rangeland ecosystems of the world have impacted on the livestock production,a key livelihood strategy in these *** paper presents perceptions of the pastoral community on the dynamics of pastoral livelihoods under three land-use types namely nomadic,semi-nomadic,and sedentary in Amboseli ecosystem located in southern *** questionnaire was used to collect data concerning household livestock herds,perceived livestock trends and their causes,importance of migration,sedentarization,and land subdivision,and were administered to respondents randomly selected from the three land-use ***:The study shows that the livestock herd size was higher in nomadic(117.1)and lower in sedentary(56.6)land-use *** majority of the respondents in nomadic(79%),semi-nomadic(73%),and sedentary(64%)reported a declining trend in household herd *** declines were mostly attributed to recurrent droughts and loss of grazing ***:Pastoralism remains an important livelihood strategy to majority of households in the study area;therefore,to achieve sustainable livelihood strategies,grazing lands should be maintained.

关键词： Herd mobility Household livestock trends Rangeland changes Community views

Treatability studies of naphthalene in soil,water and air with persulfate activated by iron(Ⅱ)

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Journal of Environmental Sciences 2020年第4期32卷 67-77页

作者： Gabriela P.Mendes vivian M.A.Magalhaes Lélia C·R·Soares Rayanne M.Aranha Claudio A.o.Nascimento Marilda M.G.R.Vianna osvaldo Chiavone-Filho Department of Chemical Engineering University of Sao PauloSPf 05508-000Brazil Department of Chemical Engineering Federal University of Rio Grande Do NorteNatalRN59072-970Brazil

Chemical oxidation was applied to an artificially contaminated soil with naphthalene(NAP).Evaluation of NAP distribution and mass reduction in soil,water and air phases was carried out through mass *** of NAP distribution and mass reduction in soil,water and air phases was carried out through mass *** importance of the air phase analysis was emphasized by demonstrating how NAP behaves in a sealed system over a 4 hr reaction *** of Experiments method was applied to the following variables:sodium persulfate concentration[SP],ferrous sulfate concentration[FeS04],and *** system operated with a prefixed solid to liquid ratio of 1:*** following conditions resulted in optimum NAP removal[SP]=18.37 g/L,[FeSo4]=4.25 g/L and pH=*** the end of the 4 hr reaction,62%of NAP was *** the soil phase,the chemical oxidation reduced the NAP concentration thus achieving levels which comply with Brazilian and USA environmental *** the NAP partitioning view,the monitoring of each phase allowed the variabilities assessment over the process,refining the knowledge of mass *** on NAP distribution in the system,this study demonstrates the importance of evaluating the presence of semi-volatile and volatile organic compounds in the air phase during remediation,so that there is greater control of the system as to the distribution and presence of the contaminant in the *** results highlight the importance of treating the contaminant in all its phases at the contaminated site.

关键词： Chemical oxidation Phase distribution Degradation kinetics PAH Soil remediation Mass balance

Spatial and temporal analysis of forest cover change in Falgore Game Reserve in Kano, Nigeria

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Ecological Processes 2017年第1期6卷 109-121页

作者： Muhammad Sabiu Suleiman oliver vivian Wasonga Judith Syombua Mbau Yazan Ahmed Elhadi Department of Land Resource Management and Agricultural Technology University of NairobiP.O.Box 29053Loresho RidgeNairobiKenya

Introduction:Multi-temporal land-use and land-cover data provides a historical vehicle for determining and evaluating long-term trends in bio-physical ***-use and land-cover assessment and mapping is one of the most useful applications of geographic information system(GIS)for planning,management,and *** study analyses the spatio-temporal pattern of forest cover dynamics for three decades in Falgore Game Reserve in Kano,*** dynamics of forest cover transition during 1985–2015 was analysed using multi-temporal Landsat ***:The spatio-temporal analysis shows that moderate woodland dominated in 1985(46%)and 2005(57%)but was replaced by open woodland in 2015 which accounts for 58%of the total area of Falgore Game Reserve(FGR)*** woodland occupied the least area of the total forest estate that varied between 17%in 1985 and 1%in *** results indicate that dense woodland,moderate woodland,and very open woodland were decreased at annual average rate of 3,1,and 0.4%.open woodland had expanded from 21,127 ha in 1985 to 53,392 ha in *** main drivers of forest resource degradation in the area were found to be excessive fuelwood collection,overgrazing,agricultural expansion,and forest ***:These findings suggest that protection strategies employed in FGR were not effective as deforestation is still evident in the *** and environmental based NGos should therefore prioritize effective and efficient conservation strategy for present and future use of forest resources,in addition to the provision of alternative livelihood sources to communities proximate to the *** will ensure the socio-economic well-being of the locals and sustainable conservation of biological diversity in the area.

关键词： Forest Trend Game reserve Falgore Degradation

Caregivers’ Perception of Unintentional Child and Adolescent Injuries in Enugu, Nigeria

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open Journal of Pediatrics 2019年第3期9卷 218-231页

作者： Christopher B. Eke obianuju o. Igbokwe vivian o. onukwuli Department of Paediatrics College of Medicine University of Nigeria Enugu Campus/University of Nigeria Teaching Hospital Ituku/Ozalla Enugu

Background: Injury is an increasing cause of childhood morbidity and mortality globally. Purpose: The objective of the study was to evaluate caregivers’ perception of unintentional child and adolescent injuries in Enugu. Methods: This was a cross-sectional descriptive study. Data were collected from caregivers of children attending the children’s outpatients’ unit of the hospital during the period of the study, who were selected consecutively using semi-structured interviewer administered questionnaire. Data were analysed using SPSS version 20.0. The level of statistical significance was set at p Results: A total of 728 caregiver-child pairs were interviewed, out of which 526 (72.3%) recalled history of injuries in their wards within the past 12months. Most of the injuries occurred at home (334;63.5%), in males 329 (62.5%), and in the 1 - 4 years age group 239 (45.4%). on further analysis, age of the child, male sex, residence in rural area and stage of child’s development significantly predicted the risk of having an unintentional injury. Majority of the interviewees had heard of first aid (432;59.3%) though only a few 23 (5.4%) actually owned well equipped first aid boxes. Most of the respondents felt that injuries in children were preventable, 429 (58.9%). However, a good number agreed that they needed clear education on preventive measures of childhood injuries, 485 (66.6%). Conclusion: Unintentional injuries occur commonly in children and are largely preventable. Appropriate health and environmental education is needed to reduce the rising incidence of injuries in children in our setting.

关键词： Childhood Injuries Caregivers’ Perception Nigeria