Physiochemical Characterization of Algae Oil from Microalgae of Nike Lake Enugu


Ejim, I. F.1 and Kamen, F.L.2
1Department of Chemical Engineering, Institute of Management and Technology Enugu State.
2Department of Chemical Engineering, Federal University of Technology, Owerri, Imo State.
E-mail: ijkeejim@ yahoo.com, felyleby@yahoo.com
ABSTRACT: Algae have emerged as one of the most promising sources of oil when grown in
C02 enriched environment. In this experiment, algae oil extract from microalgae samples
collected from Nike Lake was subjected to basic characterization analysis. The physicochemical
properties of the produced oil were measured and compared to the properties of soybean oil and
other oil seeds. Results showed that saturated fatty acid; oleic gave higher percentage (36%)
while other properties obtained were density (0.892 g/cm3), pH (4.6-5.0). refractive index (1.5),
saponification value (200g), acid value (1.9g), free fatty acid value (0.96%), iodine value (100-
120), cloud point (100C), pour point (5-80C), flash point (1100C) and moisture content (0.85%)
freezing points (31-400C) and greenish yellow in colour. Many of the properties of the algae oil
are comparable with those of soybean oil and other oil seeds.


Effect of Bulk Density on Saturated Hydraulic Conductivity


Allen A. Dusa
Department of Agricultural and Bioenvironmental Engineering,
Federal Polytechnic Mubi. Adamawa State.
E-mail: allen.dusa@gmail.com
ABSTRACT
Soil samples were taken from five local governments (Yola, Tongo, Lamurde, Fofure and Hong)
in Adamawa State. One meter deep soil was dug and composite samples were taken from 0 to
0.5m and 0.5 to 1m from each hole. A total of ten bulk samples were taken from the field to the
laboratory. The disturbed soil was mixed thoroughly before taking to the laboratory for tests.
The soil samples were subjected to 2,3,4,5,6 and 7 blows using a standard proctor hammer in a
cylindrical mold to achieve bulk densities of 1.51,1.63,1.79,1.86,1.97 and 2.01g/cm3 respectively
at 7.25% moisture content. The saturated hydraulic conductivity (Ks) was determined by falling
head permeameter method. Measurement of Ks was done in three replicates and the mean values
of Ks were recorded. Simple linear regression was done using computer to establish a functional
relationships between saturated hydraulic conductivity and bulk density of the soils studied. The
equations obtained in this study could be used to estimate the saturated hydraulic conductivity of
the soils in the study area.


Frequency-Based Design of Internal Model Controller Using the Method of Inequalities


Alabi, S.B.
Department of Chemical and Petroleum Engineering
University of Uyo, Uyo, Akwa Ibom State, Nigeria.
E-mail: sundayalabi@uniuyo.edu.ng, uniquebola@yahoo.com
ABSTRACT: In the traditional frequency domain design of an internal model controller, the
design problem is cast in terms of 2 H and  H norms of sensitivity functions in order to
obtain the parameters of a robust controller for an uncertain system. This requires the use of
weights, which are often obtained in a cumbersome trial-and-error manner. In this paper, a
computer-aided robust internal model control design method which eliminates trial-anderror
selection of weights was formulated within the context of the method of inequalities
(MoI). Lead, lag and lead-lag networks were used as weights and the model uncertainty was
described both in exact and norm-bounded forms. The robust stability and performance
criteria of the feedback system were defined as a set of algebraic inequalities. Moving
boundaries process (MBP), a search algorithm, was used to automatically and
simultaneously obtain the parameters of the controller and the weights which satisfy the
performance criteria. An uncertain system from the literature was chosen to illustrate the
new technique. The MoI-based method gave rise to internal model controller filter
parameters which in most cases are in close agreement with the filter parameters obtained
using the traditional trial-and-error method. Furthermore, the uncertainty weights obtained
via the MoI-based method are of lower order in comparison with those obtained via the
tedious trial-and-error method. It is concluded that the MoI-based method can effectively
replace the trial-and-error method for the frequency-based design of internal model
controller.


A Comparative Study of the Thermo-Physical Properties of Fuel Briquettes of Sawdust and Rice Husk


T.K. Kwadzah1 and G.O. Ogbeh2
(1 & 2)Department of Agricultural and Environmental Engineering,
University of Agriculture, Makurdi, Benue State
Email: terrumunkwadzah@gmail.com, ogbeh.gabriel@yahoo.com
ABSTRACT: Fuel briquettes were produced using rice husk and sawdust with cow dung and
waste paper pulp as binders respectively with the aid of a manually – operated hydraulic press.
These two categories of briquette were subjected to proximate and ultimate analyses in the
laboratory and their thermo-physical properties were determined. The results of the experiment
showed an average calorific value for the sawdust briquettes as (4,844Kcal/kg), while that of the
rice husk was (3347Kcal/kg); the most durable briquettes of sawdust were of moisture content
range of (5.7 – 7.1% wet basis) as compared to (4.3 – 5.2%, wet basis) recorded for the rice
husk briquette; an average density of (1.04g/cm3) was recorded for the sawdust briquette, while
that of rice husk briquette was found to be (1.06g/cm3); an average percentage ash content of
(2.5%) was recorded for the sawdust briquette, whereas a value of (2.8%) was noted for the rice
husk briquette; an average percentage fixed carbon of (20.6%) was recorded for the sawdust
briquette, while a value of (23.2%) was noted for the rice husk; also an average percentage
volatile matter of (71%) was recorded for the sawdust briquette as compared to (69.4%) value
for the rice husk briquette. From the result of these analyses, it was concluded that sawdust
possesses better qualities that would ensure good stability for storage, yield high heat content,
and better combustibility than rice husk when use for fuel briquettes under the same production
conditions.


Investigation on the Effectiveness of Some Amino Acid Derivatives in Retarding NST 44


Mild Steel Corrosion in Some Agro-Fluids
M. Alagbe
Department of Metallurgical Engineering Institute of Technology
Kawara State Polytechnic, Ilorin, Nigeria
E-mail: alagbemic@yahoo.com
ABSTRACT: This paper presents the report of an investigation and evaluation of the
effectiveness of leucine, alanine, methionine and glutamic acid inhibitors, in retarding NST
44 mild steel corrosion, in the presence of cassava and lime fluids. This work is expected to
provide useful data for the organic inhibitors capable of protecting corrosion of agro-allied
equipment and machinery which had not been possible with inorganic inhibitors because of
their poisonous nature. The results obtained indicate that alanine was observed to be more
efficient than leucine and methione by providing corrosion inhibition at molar concentrations
of 0.20M, 0.30M and 0.30M respectively. However, glutamic acid did not show a reliable
inhibition. Low inhibitor concentration was found to accelerate corrosion substantially in
the presence of cyanide and citric ions.


Minimizing Materials Wastage in Construction- A Lean Construction Approach


K. Agyekum1, J. Ayarkwa2 and T. Adjei-Kumi3
Department of Building Technology
1,2,3,Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
E-mail: agyekum.kofi1@gmail.com
ABSTRACT: It is commonly acknowledged that a very high level of waste exists in construction.
Since construction has a major and direct influence on many other industries by means of both
purchasing inputs and providing the products to all other industries, reducing waste in the
construction industry could yield great cost savings to the society. This paper aimed at
identifying the main sources and causes of materials waste on construction sites arising from
storage and handling of high waste generating building materials and employing the Lean
Construction approach to reduce such waste. The findings in this paper are based on a
structured questionnaire survey of 226 building construction organizations and consultants in
the Ghanaian building industry. The findings revealed that materials storage and handling,
operational factors, design and documentation factors and procurement factors are the main
sources of waste on building construction sites. Among the causes of materials waste are last
minute client changes, errors by tradesmen, purchased products that do not comply with
specification and lack of onsite materials control. The findings further showed that timber,
cement/mortar, concrete and blocks are the four key materials that have the highest level of
wastage on building sites. Recycling of some waste materials on site, re-using of surplus
materials where appropriate and preventing the occurrence of waste are recommended to reduce
waste. Minimizing material wastage would not only improve project performance and enhance
value for individual customers, but also have a positive impact on the national economy.


Studies on Effects of SMAW Variables on Corrosion Resistance of Austenitic Alloy

Welded Joints in Hydrochloric Acid (HCl) Medium
A. U. Iwuoha1 and I. A. Ezenugu2
1Department of Mechanical Engineering
2Department of Electrical and Electronic Engineering
1&2Imo State University, Owerri, Nigeria.
E-mail: nmatoha@yahoo.com
ABSTRACT: This paper studied the effects of Shielded Metal Arc Welding (SMAW)
variables (welding current, welding speed, electrode diameter and electrode coating type) on
corrosion behaviour of austenitic alloy (stainless steel [SS]) welded joints in hydrochloric
acid medium. A grade of AISI 300 series SS specimens in the cast state were welded with
different welding variables and the specimens subjected to corrosion studies in electrolyte of
1 molar solution of hydrochloric acid (HCl) freely ventilated at 30oC. The study adopted
electrode potential (critical corrosion potential) measurements with zinc rod reference
electrode as the index. The zinc rod potentials were converted to Saturated Calomel
Electrode (SCE) potential values. The critical corrosion potential dropped as the electrode
diameter increased. One possibility for this is that the “extended” welding time brought
about by large diameter electrodes created convenient window for microstructural change
and sensitization of base metal Heat Affected Zone (HAZ); in this state, weld decay cannot be
ruled out. The reducing reactions caused by release of hydrogen in rutile coated electrodes
compromised the metallurgical homogeneity of the weld with respect to the base metal; this
lowered the critical corrosion potential of welded joints produced with this type of electrode.
Higher welding current matched with workpiece thickness and geometry produced joints that
were more resistant to corrosion in HCl medium.


Modest Residential Building Cooling Load Components Analysis


Ibrahim, U.H., A.A. Baba and Idris, M.H.
Department of Mechanical Engineering,
Federal Polytechnic Mubi, Adamawa State, Nigeria.
E-mail: heldabuk@yahoo.com
ABSTRACT: In developing countries like Nigeria, the exacerbation of thermal discomfort in a
living space is closely associated with high cost of air conditioning systems and the epileptic
power supply. This paper therefore attempts to determine the contribution of each of the cooling
load component of a modest residential building with the view of meliorating thermal comfort by
manipulating the components that contribute significantly to the total cooling load of the
building. To achieve the set objectives, the sources of heat load both internal and external were
identified and their relative contributions to the total cooling load were determined. The results
show that external heat load which encompasses heat gain through walls, windows, roof, and
infiltration heat load, contributes about 87% of the total cooling load of the building. Significant
reduction of the external cooling load by passive measures will not only make the occupants of
the building to have relief comfort but can also reduce the size, cost and the power requirement
of the air conditioning system to be used in the building. Amelioration of thermal comfort by
mitigation of the external cooling load of a building using passive measures is recommended.


Design and Modelling of Strategic Information System 1Okpeki U. Kazeem and 2Adebari F. Adebayo


1Department of Electrical/Electronics/Computer Engineering, Delta State University, Oleh Campus
2Department of Computer Engineering, Yaba College of Technology, Yaba Lagos.
E-mail:omakazeem@yahoo.com
ABSTRACT: In this paper the design, modelling and management of information system is
presented. It takes into consideration the basic component that makes an effective
management information system. Many of information system use in many organizations
today are very large, inefficient, expensive to maintain and to a very large extent do not meet
the real needs of the organization. New applications have been added and new technology
deployed without thought given to the system functionality, performance, reliability and
security. With this strategy today’s systems will benefits from the advancement made in
system engineering and complexity management.


Construction Work Items’ Unit Rate Estimation Model for Building Contractors’ Projects


Pricing in Nigeria
Inuwa I. Ibrahim1, Iro A. Ibrahim1 and Dantong J. Sam2
1Quantity Surveying Programme, Abubakar Tafawa Balewa University, Bauchi-Nigeria.
2Department of Architecture, University of Jos, Plateau State, Nigeria.
E-mail: inuwaibrahimibrahim@yahoo.com
ABSTRACT: Contractors’ success amongst other things relies on how they are able to relate
and estimate the cost of their resources as a basis in determining their projects price in a
competitive market. Construction project pricing is highly exorbitant in Nigeria. Wrong methods
of estimation and flaws discovered in the unit rates of some completed building projects raises
questions on the accuracy of the cost estimates arrived at by consultant quantity surveyors.
Moreover, the discrepancy in the plethora of literatures on cost estimation makes estimation
complex and confusing. The study therefore aims at establishing a construction work items unit
rate estimation model for building contractors project pricing in Nigeria. This study uses historic
survey methods through an extensive literature search. The foremost thing to consider when
building unit rate is to establish the prime cost for each work item. Unit rate is the summation of
the prime cost, overhead charges and profit for each work items in a project. Therefore, Unit
Rate =N + (N×Z); where N-is prime cost and Z-is % overheads and profits. Mathematically; N=
MC+LC+PC. Numerical contribution of each constituent per unit of work is: Mc ≥ 0; Lc 􀀀 0; Pc ≥
0 and; Zc 􀀀 0. The model is comprehensible, its applicability is compatible with any
circumstance, it facilitates error free rates and can improve productivity. The model can be use:
for effective management of construction project; for teaching and understanding the basic
principle in rate computation and; in attaining uniformity in unit rate computation in the
construction industry.


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