oalib

OALib Journal期刊

ISSN: 2333-9721

费用：99美元

投稿

时间不限

( 2673 )

( 2672 )

( 2454 )

( 2208 )

自定义范围…

匹配条件： “O.C. Ajayi” ，找到相关结果约368010条。
列表显示的所有文章，均可免费获取
第1页/共368010条
每页显示 条
Contributions of Agroforestry Research and Development to Livelihood of Smallholder Farmers in Southern Africa: 2. Fruit, Medicinal, Fuelwood and Fodder Tree Systems
F.K. Akinnifesi,G. Sileshi,O.C. Ajayi,P.W. Chirwa,F.R. Kwesiga,R. Harawa
Agricultural Journal , 2013,
Abstract: Integration of trees on farms provides opportunities for improving diversification and range of livelihood portfolios for smallholder farming households in southern Africa. This study synthesizes 2 decades of research and development on agroforestry interventions in southern Africa. In addition to important horticultural fruits such as mangoes and citrus, indigenous fruit trees such as Uapaca kirkiana, Ziziphus mauritiana, Adansonia digitata and Sclerocarya birrea are widely preferred by farmers and traded in the southern Africa region. Domestication of these fruit tree species has advanced and superior clones with multiple-traits have been identified, tested and disseminated to farmers. Through application of vegetative propagation techniques, the time taken for fruiting of these miombo species has been reduced substantially. More than 12.000 farmers have been trained in nursery establishment and over 6000 farmers are involved in on-farm testing of indigenous fruit trees in the field and homesteads in the five countries. The introduction of fast-growing legumes on farms has improved production of fuel wood, fodder, timber and other products and services. In Tanzania alone, over 27.500 farmers have planted fodder trees in the last 6 years. Financial analysis carried out on fodder, rotational woodlots and fruit trees indicated that these agroforestry enterprises were profitable and exhibited positive financial ratios. The provision of quality germplasm, awareness creation and training, in addition to policy interventions are critical considerations for widespread adoption of these technological options.
Reader, author editor triumvirate.
O.C. Tuncay
Hellenic Orthodontic Review , 2003,
Abstract:
Contributions of Agroforestry Research to Livelihood of Smallholder Farmers in Southern Africa: 1. Taking Stock of the Adaptation, Adoption and Impact of Fertilizer Tree Options
F.K. Akinnifesi,P.W. Chirwa,O.C. Ajayi,G. Sileshi,P. Matakala,F.R. Kwesiga,H. Harawa,W. Makumba
Agricultural Journal , 2013,
Abstract: Agroforestry practies involving fertilizer trees managed in sequential and simultaneous tree-crop systems are key to achieving sustainable food production in Southern Africa as they offer a wider scope for resource-stressed farmers to produce sufficient food for consumption and markets, even where land scarcity and soil fertility are major constraints. In these systems, maize yields have generally increased from less than a tonne per hectare to two or more tonnes, in Malawi, Tanzania, Zambia and Zimbabwe and they have been shown to be comparable to fertilized fields. Application of micro doses of inorganic fertilizers (especially N) in tree-crop systems has generally increased the synergy in nutrient availability thereby producing higher maize yields than unfertilized maize. Fertilizer tree systems are more productive and economically more profitable than unfertilized maize system and the economic impact is high, estimated at US$ 2 million in 2005 for Zambia alone. Fertilizer tree systems practiced on a 0.20 ha area increased maize consumption for a family of five by extra 57-143 days. Training of trainers, farmer-to-farmer extension and support to existing initiatives were the most effective pathways of disseminating proven technologies. Impact assessment studies in Malawi, Mozambique and Zambia indicate that 66-83% of farmers are aware of the contribution of fertilizer tree systems to food production, cash income, fuelwood and their overall livelihoods. However, the slow rate of adoption of fertilizer tree options under farmer s resource-poor conditions underscores the magnitude of the challenge for stimulating long-term investment. There is need to create enabling policy support that would make quality germplasm available in the right amount and time and provide awareness and training to farmers on such knowledge-intensive technologies.
Synthesis and characterization of nitroacyl-5-oxo-pyrazole and its vanadium(V), iron(III) and cobalt(II) complexes
Martin O.C. Ogwuegbu
Bulletin of the Chemical Society of Ethiopia , 1999,
Abstract:
GEOLOGY AND DEPOSITIONAL ENVIRONMENT OF CAMPANO-MAASTRICHTIAN SEDIMENTS IN THE ANAMBRA BASIN, SOUTHEASTERN NIGERIA: EVIDENCE FROM FIELD RELATIONSHIP AND SEDIMENTOLOGICAL STUDY
Adeigbe,O.C; Salufu,A. E;
Earth Sciences Research Journal , 2009,
Abstract: the study area lies within the anambra basin and it is made up of enugu shale, mamu formation, ajali sandstone, and nsukka formation. this study aimed at determining the geology and depositional environmental of these formations through field relationship and grain size distribution morphologic studies. the field data shows enugu shale as fissile, light grey with extraformational clast which graded into mamu formation which is made up of shale, coal and sandy shale. it passes upward into ajali sandstone which is characterized by cross beds, herringbone structures and ophiomorpha burrows. the youngest formation within the basin is nsukka formation. the granulometric study of mamu formation shows fine to medium grains, coarse, medium to fine grain for mamu and ajali formation respectively. the standard deviation indicates poorly sorted. the kurtosis shows leptokurtic, platykurtic to very leptokurtic for both while the skewness values indicate positive and symmetrical in all except for ajali sandstone that is negatively skewed. the bivariate and the multivariate results reveal shallow marine and fluvial deposits for both mamu formation and ajali sandstone respectively. the paleocurrent direction of ajali sandstone indicates southwest while the provenance is northeast. the fissility of enugu shale suggests that it was deposited in low energy environment, distal to proximal lagoon environment. the presence of extraformatonal clast within enugu shale indicates fluvial incursion. however, the textural analysis of mamu formation suggests a sediment deposited in a low energy environment which favoured deposition of fine to medium size sediments that is, estuary environment. textural result of ajali sandstone in the study area coupled with the field data such as herring-bone structures, and ophiomorpha burrows, revealed that ajali sandstone was deposited in a tidal environment probably littoral environment. while the light grey colour observed in the nsukka formation suggests
A Comparative Analysis Of The Natural Law Doctrine In Ancient And Medieval Periods
O.C. Macaulay-Adeyelure
Lumina , 2010,
Abstract:
GEOLOGY AND DEPOSITIONAL ENVIRONMENT OF CAMPANO-MAASTRICHTIAN SEDIMENTS IN THE ANAMBRA BASIN, SOUTHEASTERN NIGERIA: EVIDENCE FROM FIELD RELATIONSHIP AND SEDIMENTOLOGICAL STUDY
O.C Adeigbe,A. E Salufu
Earth Sciences Research Journal , 2009,
Abstract: The study area lies within the Anambra Basin and it is made up of Enugu Shale, Mamu Formation, Ajali Sandstone, and Nsukka Formation. This study aimed at determining the geology and depositional environmental of these formations through field relationship and grain size distribution morphologic studies.The field data shows Enugu Shale as fissile, light grey with extraformational clast which graded into Mamu Formation whichis made up of shale, coal and sandy shale. It passes upward into Ajali Sandstone which is characterized by cross beds, Herringbonestructures and Ophiomorpha burrows. The youngest formation within the basin is Nsukka Formation.The granulometric study of Mamu Formation shows fine to medium grains, coarse, medium to fine grain for Mamu and Ajali Formation respectively. The standard deviation indicates poorly sorted. The kurtosis shows leptokurtic, platykurtic to very leptokurtic for both while the skewness values indicate positive and symmetrical in all except for Ajali Sandstone that is negatively skewed.The bivariate and the multivariate results reveal shallow marine and fluvial deposits for both Mamu Formation and Ajali Sandstone respectively. The paleocurrent direction of Ajali Sandstone indicates southwest while the provenance is northeast.The fissility of Enugu Shale suggests that it was deposited in low energy environment, distal to proximal lagoon environment.The presence of extraformatonal clast within Enugu Shale indicates fluvial incursion. However, the textural analysis of Mamu Formation suggests a sediment deposited in a low energy environment which favoured deposition of fine to medium size sediments that is, estuary environment. Textural result of Ajali Sandstone in the study area coupled with the field data such as Herring-bone structures, and Ophiomorpha burrows, revealed that Ajali Sandstone was deposited in a tidal environment probably littoral environment. While the light grey colour observed in the Nsukka Formation suggests sediments deposited under an oxidizing marine environment.
Scanning electron microscope description of the Afowo oil sand deposits in south-western Nigeria
Akinmosin,A; Adeigbe,O.C; Oyemakinde,O.O;
Earth Sciences Research Journal , 2011,
Abstract: the afowo oil sand deposits in parts of southwestern nigeria were described by scanning electron microscope for characterizing the reservoir sands, based on their clay content. twelve core oil sand samples were collected, six of which were selected for analysis based on the similarities in their physical and textural characteristics. the prepared oilsandsamples were then described byscanning electron microscope studies (vega tescan/lmu scanning electron microscope-sem). the analysis revealed that the oil sands contained minerals which had been precipitated and occurred as pore filling cement; these minerals included sheet kaolinite, vermiform kaolinite, k- feldspar, pyrite crystals, and corrosion quartz and corrosion feldspar. the sem images also showed 2-4 μm micro pores and 2-5μm fractures. the study showed that the clay minerals contained in the afowo formation's reservoir rocks were mainly kaolinite which was not expected to have any negative effects on reservoir quality, especially during enhanced oil recovery operations.
Scanning electron microscope description of the Afowo oil sand deposits in south-western Nigeria
A Akinmosin,O.C Adeigbe,O.O. Oyemakinde
Earth Sciences Research Journal , 2011,
Abstract: The Afowo oil sand deposits in parts of Southwestern Nigeria were described by scanning electron microscope for characterizing the reservoir sands, based on their clay content. Twelve core oil sand samples were collected, six of which were selected for analysis based onthe similarities in their physical and textural characteristics. The prepared oil sand samples were then described by scanning electron microscope studies (VEGA TESCAN/LMU scanning electron microscope-SEM). The analysis revealed that the oil sands contained minerals which had been precipitated and occurred as pore filling cement; these minerals included sheet kaolinite, vermiform kaolinite, k- feldspar, pyrite crystals, and corrosion quartz and corrosion feldspar. The SEM images also showed 2-4 μm micro pores and 2-5μm fractures. The study showed that the clay minerals contained in the Afowo formation's reservoir rocks were mainly kaolinite which was not expected to have any negative effects on reservoir quality, especially during enhanced oil recovery operations
Erythrocyte glucose-6-phosphate dehydrogenase activity assay and affinity for its substrate under "physiological" conditions
Leite, A.A.;Barretto, O.C. de O.;
Brazilian Journal of Medical and Biological Research , 1998, DOI: 10.1590/S0100-879X1998001200004
Abstract: glucose-6-phosphate dehydrogenase (g6pd) activity and the affinity for its substrate glucose-6-phosphate were investigated under conditions similar to the physiological environment in terms of ionic strength (i: 0.188), cation concentration, ph 7.34, and temperature (37oc). a 12.4, 10.4 and 21.4% decrease was observed in g6pd b, g6pd a+ and g6pd a- activities, respectively. a km increase of 95.1, 94.4 and 95.4% was observed in g6pd b, g6pd a+ and g6pd a-, respectively, leading to a marked decrease in affinity. in conclusion, the observation of the reduced activity and affinity for its natural substrate reflects the actual pentose pathway rate. it also suggests a much lower nadph generation, which is crucial mostly in g6pd-deficient individuals, whose nadph availability is poor.
第1页/共368010条
每页显示 条


Home
Copyright © 2008-2020 Open Access Library. All rights reserved.