68 research outputs found
Mathematical Modeling of High Temperature and High Pressure Dense Membrane for Separation of Hydrogen from Gasification
There is an increasing interest in the use of inorganic membranes as a means of separating gas mixtures at high temperatures and pressures. The most important membrane properties are high permeability and selectivity, and good mechanical, thermal and chemical stability. Dense Pd-based composite membranes are suitable for hydrogen separation and use in catalytic membrane reactors because of their high permeability, good surface properties and high selectivity for hydrogen transport. At UTSI, Pd/AlO23 membranes were prepared by a special method of laser based thermal deposition of the thin film Pd on a ceramic substrate by Nd-YAG laser irradiation of PdCl2 coating on a γ-alumina substrate. This work reports a mechanistic model for the hydrogen permeation process in the Pd/Al2O3 composite membrane developed at UTSI. The model takes into account the well known kinetics of hydrogen adsorption/desorption in the palladium surface and hydrogen permeation in the porous alumina layer. Reasonable values for all mass transfer rate parameters were estimated based on the available surface science and membrane permeation literature. One set of experimental data (at 11000F) was used to determine the best values of the necessary rate parameters. These values of rate parameters were then used to predict and compare the experimental hydrogen flux data at two other temperatures (90000F and 1300F). The results demonstrated that the atomic hydrogen diffusion through the palladium layer and pore diffusion in the porous alumina support both played important roles in the permeation of hydrogen through the composite Pd/Al2O3 membrane. A simplified resistance model was also employed to analyze the permeation behavior of hydrogen through the Pd/Al2Omembrane to identify the major resistances to the mass transfer. The results indicated that the mass transfer in the Pd layer contributed about 90% of the total mass transfer resistance. Our model calculations also indicated that by reducing the thickness of the Pd layer to about 18 μm, the DOE goal of \u3e 60 scfh/ft2 for hydrogen gas flux can be achieved. This can also be achieved by reducing the thickness of the Pd layer to about 20 μm and reducing the thickness of the alumina support layer to about 2 mm or by increasing it’s porosity to about 50%.
Integration and Conflict Management among Igbo Migrants Farmers and Odolu/Igalamela Indigenes of Kogi State Nigeria
Migrant farm workers suffer immensely from separation, isolaton, and discrimination due to their poor integration into the host communities. The study was designed to asses the extent of integration, causes and management of conflict among migrant farmers and indigenous people of Odolu/Igalamela in Kogi state. A total of 100 respondents were purposively selected from five out of nine town communities that make up Odolu/Igalamela ethnic region. A semi structured interview schedule was used to collect information from the respondents. Percentage, mean score and factor analysis were used to analyse the data obtained. The average number of years spent by the respondents in the destination area was 11.5 years. Irrespective of this number of years spent in the area, migrant farmers had not been properly integrated into the host communities. Majority of them (84.4%) had no land on freehold, although there were a number of intermarriages, there were also many cases of divorce (72%) and majority of them (75%) still bury their dead in the place of origin and hold ceremony at the same place. Majority (86%) of the migrant farmers had no title or leadership position in the destination area but belonged to migrant farmers association mainly for ceremonial and welfare purposes. There were no serious types/causes of conflict among migrant farmers but migrant farmers had conflicts with the indigenes mainly due to jealousy. These conflicts were resolved by formal, informal and interpersonal methods. The study emphasized the need to initiate policies that will favour the settlement of migrant farmers in the destination area as integration and consequent peaceful atmosphere ensure sustained agricultural production. Key words: Migrant Farmers Agriculture Integration conflic
Lessons from Agricultural Policies and Programmes in Nigeria
The study reviewed several agricultural policies and programmes that were initiated in Nigeria. Through this, objectives/goals, achievements as well as problems that hindered realization of the dreams of the policies and programmes were known. Gaps in their invention, execution and management were also identified. Solutions/recommendations were then proffered based on these gaps as lessons/guide for future policies and programmes inventions. Key words: agriculture policies programmes Nigeri
Constraints to Vegetable Production among Women in Enugu North Agricultural Zone of Enugu State
The study was carried out to ascertain constraints to vegetable production in Enugu Agricultural zone of Enugu State. A total of seventy one respondents were randomly selected for the study. A structured interview schedule was used to enlist information from the respondents. Statistical tools such as factor analysis and percentage were used to analyze the data obtained. The findings of the study were: Majority (88.7%) Â grew fruited pumpkin (Telferia occidentalis). Majority (92.9%) used communal land and family labour (95.7%) to produce their vegetables. The major agronomic practices were direct sowing of seed (57.7%), mixed cropping (56.3%), organic manure (67.6%), staking (8.5%), broadcasting method of manuring (66%) and cutting with knife (method of harvesting) (91.5%). The mean annual income at main season was N6099.09 while that of off-season was N4387.8. Financial and agronomic/incentives problems were major constraints associated with vegetable production in the study area. It becomes important to transfer innovations on agronomic/management practices of vegetable to the area. This will boost output generally and increase income substantially thereby increasing their standard/level of livin
Constraints to Vegetable Production among Women in Enugu North Agricultural Zone of Enugu State
The study was carried out to ascertain constraints to vegetable production in Enugu Agricultural zone of Enugu State. A total of seventy one respondents were randomly selected for the study. A structured interview schedule was used to enlist information from the respondents. Statistical tools such as factor analysis and percentage were used to analyze the data obtained. The findings of the study were: Majority (88.7%) Â grew fruited pumpkin (Telferia occidentalis). Majority (92.9%) used communal land and family labour (95.7%) to produce their vegetables. The major agronomic practices were direct sowing of seed (57.7%), mixed cropping (56.3%), organic manure (67.6%), staking (8.5%), broadcasting method of manuring (66%) and cutting with knife (method of harvesting) (91.5%). The mean annual income at main season was N6099.09 while that of off-season was N4387.8. Financial and agronomic/incentives problems were major constraints associated with vegetable production in the study area. It becomes important to transfer innovations on agronomic/management practices of vegetable to the area. This will boost output generally and increase income substantially thereby increasing their standard/level of livin
Responsiveness of Extension Workers to Climate Change in Anambra State, Nigeria
Given the role agricultural extension will play in sensitizing and educating farmers on how to mitigate and adapt to climate change, the study was carried out to ascertain the responsiveness of extension workers to climate change. Fifty one extension workers proportionately selected from the four agricultural zones in the state were used for the study. Data were analyzed with percentage, mean score and factor analysis. All (100%) of the respondents had heard about climate change. On average they heard it in 2003 and noticed it in 2002.They sourced information on climate change from fellow extension workers (77.8%) and newspapers (76.6%).Only “giving reports with respect to climate or weather of the environment (58.8%) was activity occurring/undertaken by extension workers with respect to climate change. Prediction/ forecasting of weather (92.2%) was area the extension workers mostly needed training on climate change. Manpower development/training, institutional/linkage and staff incentive problems were factors constraining responsiveness of extension workers in Anambra state to climate change. The study recommends the need to acquaint extension workers with knowledge on climate change and climate related issues by including it in the programme of ADP. In this way the extension workers especially front line extension agents can educate and help farmers mitigate and adapt to the impact of climate change for increased agricultural output
Effects of Land Degradation on Agriculture in Anambra State: Issue for Agricultural Extension Policy
The study examined the effects of land degradation on agriculture in
Anambra state. Two Local Government Areas were purposively selected
from the state while a town community was purposively selected from
each of the Local Government Areas. Proportionate sampling technique
was used to select 50% of the villages in each town and a total of 112
respondents were used for the study. Frequency, percentage and mean
score were used for data analysis. Some findings of the study were:
erosion (M=2.50), excessive use of inorganic manure and agrochemicals
(M=2.45) and construction of roads and houses (M=2.42), were serious
causes of land degradation in the area. High cost of input in farming
(M=2.52) and rural urban migration were major effects of land
degradation in the area. Evidences of the effects of land degradation in
the area were: estimated mean monthly income dropped from N35,000 in
2005 to N15,000 in 2009. Mean farm size decreased from 1.5 hectare in
2005 to 0.75 hectare in 2009. Percentage of respondents rearing goat
dropped from 80.4% to 41.1% while percentage of respondents growing
cassava dropped from 100% to 80.4% within these years. Majority of the
respondents pointed out aforestation (77.7%), controlled grazing (75.9%)
as strategies they use to prevent land degradation in the area. They
sourced information on land management and conservation practices
from town criers (M=2.52) and radio (M=2.35).The study enumerated the
need to include land management and conservation practices into
agricultural extension programme (ADP) so that their clientele( farmers)
can be equipped and involved practically in conservation/management of
land for improved agricultural output and better future
Responsiveness of Extension Workers to Climate Change in Anambra State, Nigeria
Given the role agricultural extension will play in sensitizing and educating farmers on how to mitigate and adapt to climate change, the study was carried out to ascertain the responsiveness of extension workers to climate change. Fifty one extension workers proportionately selected from the four agricultural zones in the state were used for the study. Data were analyzed with percentage, mean score and factor analysis. All (100%) of the respondents had heard about climate change. On average they heard it in 2003 and noticed it in 2002.They sourced information on climate change from fellow extension workers (77.8%) and newspapers (76.6%).Only “giving reports with respect to climate or weather of the environment (58.8%) was activity occurring/undertaken by extension workers with respect to climate change. Prediction/ forecasting of weather (92.2%) was area the extension workers mostly needed training on climate change. Manpower development/training, institutional/linkage and staff incentive problems were factors constraining responsiveness of extension workers in Anambra state to climate change. The study recommends the need to acquaint extension workers with knowledge on climate change and climate related issues by including it in the programme of ADP. In this way the extension workers especially front line extension agents can educate and help farmers mitigate and adapt to the impact of climate change for increased agricultural output
Effects of Land Degradation on Agriculture in Anambra State: Issue for Agricultural Extension Policy
The study examined the effects of land degradation on agriculture in
Anambra state. Two Local Government Areas were purposively selected
from the state while a town community was purposively selected from
each of the Local Government Areas. Proportionate sampling technique
was used to select 50% of the villages in each town and a total of 112
respondents were used for the study. Frequency, percentage and mean
score were used for data analysis. Some findings of the study were:
erosion (M=2.50), excessive use of inorganic manure and agrochemicals
(M=2.45) and construction of roads and houses (M=2.42), were serious
causes of land degradation in the area. High cost of input in farming
(M=2.52) and rural urban migration were major effects of land
degradation in the area. Evidences of the effects of land degradation in
the area were: estimated mean monthly income dropped from N35,000 in
2005 to N15,000 in 2009. Mean farm size decreased from 1.5 hectare in
2005 to 0.75 hectare in 2009. Percentage of respondents rearing goat
dropped from 80.4% to 41.1% while percentage of respondents growing
cassava dropped from 100% to 80.4% within these years. Majority of the
respondents pointed out aforestation (77.7%), controlled grazing (75.9%)
as strategies they use to prevent land degradation in the area. They
sourced information on land management and conservation practices
from town criers (M=2.52) and radio (M=2.35).The study enumerated the
need to include land management and conservation practices into
agricultural extension programme (ADP) so that their clientele( farmers)
can be equipped and involved practically in conservation/management of
land for improved agricultural output and better future
Knowledge and Roles of Non Governmental Organizations (NGOs) in Climate Change Mitigation and Adaptation in Anambra State
The study ascertained knowledge and perceived roles of state based-Non
Governmental Organizations (NGOs) in climate change mitigation and
adaptation in Anambra State, Nigeria. Multistage random sampling technique was employed to select thirty five respondents from 4 local government areas and 7 NGOs in the state while data were collected with questionnaire. Percentage and mean scores were used in analyzing the data. Results revealed that greater proportion (60%) of NGO members were not aware of climate change while about 63% indicated that issues on climate change have not been included in their programme. They perceived major causes of climate change as over industrialization (M=2.77) and use of automobiles (M=2.74) while land degradation and over flooding (M=2.77 each) were major effects of climate change. Proper land use and management (M=2.89) and reforestation/ (M=2.83) were mitigation measures while minimum tillage (M=2.74) and use of resistant varieties (M=) were adaptive measures to climate change as perceived
by them. They further perceived creation of awareness and sensitization of rural people/farmers about climate change (77.1%each) and helping government in enforcement of policies and laws that will help to mitigate climate change (57.1%) as roles they can play in climate change mitigation and adaptation. They did not perceive any major problem that can mar their contributions to climate change issue. The study emphasized on the need for private sector especially NGOs investment and participation in global and sensitive issues like climate change. This will go a long way in discovering and disseminating quick and useful information on climate change and probably ultimate solution to it
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