DEPARTMENT OF CHEMISTRY
PhD. Thesis- Chemistry
S/NO
1.
NAME
Habiba Muda
Lawal
REG. NO
PG/0350
TITLE OF
THESIS
THE ELECTRONTRANSFER
REACTIONS OF
PARAROSANILIN
E CHLORIDE
(BASIC FUCHSIN)
AND
TRISOXALATOCO
BALTATE (III)
ION IN ACIDIC
MEDIA
YEAR
OF
GRAD.
APRIL
1997
ABSTRACT
The kinetics and Mechanism of the redox reactions
of Pararosaniline chloride (herein referred to as
Fuchsin) with the oxyanions (S2 02 8- , S2 O2-5 ,S2-3 ,
and IO-4 ) have been studied in aqueous acetic acid,
1=1. OM (CH3COONa) at 25°C ± O.1°C. The
stoichiometry is 1:1 in all the four systems. The rate
of the reaction is first order in each oxidant and
reductant for the S2O2-5 and S2O2-8 reactions, while
the reaction is zero order for [S2-3and (IO—4)].
Pararosaniline chloride is reduced by S2-3 andS2O2-5
and the order of reactivity is K2(S2O2-5)>K1(S23).Peroxydisulphate and periodate oxidize fuchsin
and the order of reactivity is k2(S2O2-8)>K1(IO-4) .
These rates were rationalized on the basis of
standard redox potentials. The rates of the reactions
show an inverse acid dependence except the 10-4
system which is independent of [H+]. The overall
rate equation for the reactions can be given as
_d [Fuchsin] = b+c[H +] -1 [Fuchsin][XOn-m]
dt
XOn-m=S2O2-8,S2O2-5
d/dt [Fuchsin] = a [H]-1[Fuchsin] forSO2-3
reaction
-d· .
dt[Fuchion] = k[Fuchsion] for I04 reaction
spectroscopic investigation suggested the presence
of shortlived intermediate complex in the SO2-3 and
AREAS OF
FURTHER
RESEARCH
IO-4 reactions.There was no kinetic evidence in
favour of the complex formation in all the four
systems.
The S2O2-5 and SO2-3 reactions are proposed to
be occurring by either the outer-sphere mechanism
or the inner-sphere mechanism.
The S2O2-8 is postulated to occur by the outer sphere
while the 10-4 is proposed to occur by the inner
sphere msechanism.
Similarly, the kinetics of the reduction of
trisoxalatocobaltate (III) with some reductants (Lascorbic acid (H2A), 1, 4-benzenediol (H2Q), Lcysteine (RSH), L-Methionine (RSCH3) and
Mercaptoacetic acid (GSH) have been studied in
aqueous perchloric acid (HCIO4) L-ascorbic acid,
1,4-benzenediol and mercaptoacetic acidS and
hydrochloric acid (L- cysteine and L-Methionine) at
25.0 O.l°C. I = 1.0M (NaCI04, or LiCL04, or NaCI).
Two moles of oxidant were consumed by one mole
each of ascorbic acid and 1,4-benzenediol, and one
mole oxidant to one mole reductant for the other
three systems. All reactions are first-order in both
oxidant and reductant, and show acid dependence
except the 1, 4-benzenediol and the L- Methionine
reactions.
The kinetic data are consistent with the following
equations.
--Id/2dt
[CO(OX)2-3=b+c[H+][CO(OX)3-3][H2A]
H2A=ascorbic acid.
-d/dt[CO(OX)3-3]=a[H+][CO(OX)3-3][RSH]
RSH=L-cysteine,mercaptoacetic acid.
-1d/2dt [CO(OX)3-3]=K2[CO(OX)3-3][H2O]
H2O=1,4-benzenediol.$
-d/dt[CO(OX)33-]=K2[CO(OX)3-3][RSCH3]
RSCH3=L-methionine.
The rate of reduction of the CO(III) complex is
mercaptoacetic acid (K2=3.35x10-3M-1 S-1)
2.
USMAN O.A.
SHUAIBU
PGS/9495/00548
SOME PLANT
SPECIES AS
BIOINCATORS OF
HEAVY METALS
IN BAUCHI
MUNICIPALITY
2001
>ascorbic acid (K2=9.9x10-4 M-1 S-1) L-cysteine
(K2=3.30x10-4M-1S-1)>1,4-benzenediol (1.65x10-4
M-1 S-1)>Methionine
(K2=1.43x10-3 M-1S-1).
These rates are rationalized on the basis of
intramolecular hydrogen bonding.Both the results of
spectroscopic investigations and Michaelis-Menten
analysis show no evidence of intermediate complex
formation of significant stability except in the
mercaptoacetic acid system.
The experimental results obtained are in favour of
the outer-sphere mechanism for all systems except
mercaptoacetic acid reaction ,for which the inner
sphere mechanism has been postulated.
Trace metal concentrations in Calotropis
procera, (Cp) Pinus sylvestris lim
(Psl), Psidium guajava (Pg) and
Magnifera indica (Mi) leaves were
determined using flame atomic absorption
spectrometry. Calotropis procera showed
the highest concentration factor for Zn (3.120), Cu
(2.047), Pb (4.123) and Cd (2.19), while Pinus
sylvestris lim was highest for Cr (3.380) and
Fe (2.830). Psidium guajava has highest
concentration factor for Ni (3.72) and
Magnifera indica for Mn (3.57). These
results showed that the enrichments vary with the
plant species such that essential elements such as
Fe, Cu, Mn, and Zn were more enriched than Cd,
Cr, Pb and Ni, which are toxic.
3.
SALAMI
SUNDAY
JOHN
PGS/9596/00578
EUCALYPTUS
2004
CAMALDULENSIS
AND
AZADIRACHITA
INDICA AS
BIOINDICATORS
OF HEAVY
METALS IN
BAUCHI, GOMBE
AND PLATEAU
STATES
ent vh tem evehHst it rte n teht leaves and bark
of Eucalyptus camaldulensis(Ec) and Azadirachta
indica (Ai) obtained from Bauchi, Gombe and
Plateau States were determined using Atomic
Absorption Spectrophotometry (AAS) with the aim
of indicating the metal loads of the environment.
SimiIlarly, the sulphur content and pH of the bark
water extracts were determined to indicate
environment acidity. The rshhtlhe hu dswe lu le luse
shhssle testsessl Fe, Mn, Zn, Cu, Cr and Co were
preferencially accumulated by the leaves compared
to the bark as the leaf to bark metal concentration
ratios were greter than 1.00. The Pattern of
accumulation
is
such
that
Fe>Mn>Zn>Cu>Pb>Cd>Cr>Co in both leaves and
bark.Eucalyptus camaldulensis leaf samples from
Bauchi State had the highest concentration of
Zn(32.00+ 9.83 ug/g), those from Gombe had the
highest concentrations of Co,Cu,Pb,Fe and
Cr(1.67+ 0.96 ug/g,9.17+ 2.46ug/g, 6.98+0.81ug/g,
58.0+7.35ug/g and 5.78+1.40ug/g respectively),
while samples from Plateau State had the highest
concentration of Mn 42.09+7.91ug/g and Cd
9.11+1.66ug/g.Eucalyptus camaldulensis bark
samples from Gombe State had the highest
concentration
of
Co
1.15+0.49ug/g,Pb7.30+1.16ug/g,Fe 54.56+7.11ug/g
and Cr 5.46+1.33ug/g, while samples from Plateau
State had the highest concentration of
Mn33.96+15.75ug/g,Cu12.06+2.15ug/g,
Cd9.34+3.3.80ug/g and Zn23.03+7.53ug/g.The Co
content of Azadirachta indica leaves in Bauchi
State was 1.22+0.48ug/g.Pb, Fe and Cr
concentration were highest in Gombe State, while
Mn,Cu and Cd concentrations were highest in
Azadirachta
indica
leaves
in
Plateau
State.Azadirachta indica bark samples from Gombe
State had the highest concentrations of Co,Pb,Fe
and Cr while those from Plateau State gave the
highest concentration of Mn,Cu,Cd and Zn. Their
high concentrations indicate pollution from
different sources such as industrial, commercial,
mining activities andvehicle emmisions. Eucalyptus
camaldulensis and Azadirachta indica bark samples
from Gombe State gave the highest S
concentration.The highest PH in Eucalyptus
camaldulensis bark was from Bauchi, while the
highest value for Azadiachta indica was in Plateau
State. The barks recorded the changes in the
environment as the PH varied with age, health,
thicktness of bark, substrate upon which they grow
and length of storage in the laboratory.
4.
EKANEM
ENO OKON
PGS/96/
00531
PESTICIDAL
AUGUS
RESIDUES IN
T 2004
SOILS AND
SELECTED CROPS
IN SAVANNA
ZONES OF
BAUCHI STATE
OF NIGERIA
Pesticides residues in soils and selected crops from
the savanna zones of Bauchi State have been
investigated. Farm station survey showed the
predominance of 8 out of 31 pesticides with
Ronstar 25EC, Basagram PL2, Galex 5OOEC, 2,
4-D Amin 720SL, Atrazine 95%, Rifit Extra
500EC, and Gamalin. The active igredient were
mainly organochlorines. The pH range of the
soils studied was 5.I-6.8, showing moderate to slight
acidity. The pesticide residue levels obtained
from the treated soils based on 2.5kg ha-I pesticide
application was Dass (6.71mgkgl), and Alkaleri
(0.72mgkg-l) and for the post-harvested crops from
treated soils was MIS (MZG, 0.60 mgkg-I) and
(MTG O.O5mgkg-l) for the highest and lowest
values respectively. Pesticides residues identified in
the treated soils were Dieldrin; Atrazine, Atrazine
related residues Nuvan, and Ronstar, and for
crops were 2, 4-D and Atrazine related residues
respectively. Evaluation of the soil characteristics
to residue stress, showed a positive correlation (p =
0.05) with organic matter, clay content, cation
exchange capacity, PH and temperature, such that
the continuous application of these identified
organochlorines could lead to high persistency with
time, rendering the soil and agricultural produce
harmful to end users.
5.
ABDULLAHI
AISHA
LARABA
PGS/97ISOLATION AND
98/402003 PHARMACOLOGI
CAL STUDIES OF
THE EXTRACTS
OF TERMINALIA
LAXIFLORA Engl.
And Diels
NOVE
MBER,
2005
The extracts of the bark of Terminalia
The
laxiflora inhibited the spontaneous pendular
studies conducted
movement of the isolated rabbit jejunum and
on
attenuated
acetylcholine-induced
laxiflora revealed
contractions. These substances (100, 200
that the plant is
and 400 mg/kg) also caused a dose-
bioactive and has
dependent
great potential in
decrease
of
gastrointestinal
array
Terminalia
transit and markedly protected mice against
primary
castor
healthcare.
oil-induced
toxicological
studies
diarrhoea.
revealed
that
The
the
intraperitoneal LD50 of the aqueous root and
of
The
pharmacological
studies confirmed
stem bark extracts were far above the
its
concentrations required for the described
in treating gastro
pharmacological activities. To aid isolation,
intestinal
alkylation and acetylation reactions were
disorders.
carried out on some of the extracts, and the
toxicological
spectral data were analysed to assess the
assessment of the
efficiency of the reactions. The proton and
plant revealed the
13
safe dose of the
C-NMR spectral data revealed shikimic acid,
and
the
presence
of
carboxylic
acids,
stem
effectiveness
and
The
root
alcohols and esters were confirmed by
barks - the parts
appropriate phytochemical techniques.
that are used in
V
I
ethno-medicine.
I
The
chemical
evaluation of the
plant showed the
presence
of
shikimic acid and
other
carboxylic
acid
containing
compounds. The
IR analysis and
the alkylation and
acetylation
reactions confirm
the presence of
hydroxyl groups
in extracts.
7.
MUDI
SULEIMAN
YUSUF
PGS//005
02
PHYTOCHEMICA
L SCREENING OF
Vitex doniana
SWEET
(Verbenaceae) FOR
BIOACTIVE
COMPOUNDS
JULY
2006
Six plants locally identified to exhibit
medicinal properties when in combination
of two or more were selected and screened.
The dried and powered samples of the
selected parts of these plants were
extracted sequencially with hexane,
chloroform, ethyl acetate and ethona.These
extract give fractions that were found to be
active agaist brine shrips and someselected
microorganisms.With ethonal extract (VD)
of vitex donianal recording the highest
activity against Brine Shrimp Test (BST), with
LC50 value 515ug/ml (1219-281), and all the
selected microorganisms.
On the best of these results, the ethanol
extract (VD) of V.doniana bark was
extracted on a large scale and column
chromatographed on silica gel.Fraction
VD17 was found to be the most active
against BST and some selected
microorganism.
These fractions, VD17-198, VD17-88103,
VD17-529-111 and VD17-529-185, were
isolated from fraction VD17 using
chromatography, and the isolates were
characterized to be compounds 1,2,3,and4
based on the available spectral data.
Compound VD17-198 was found to be active
against BST, LC50 value of 4.7ug/ml 929-5).
C0mpound VD17-88-103 has no activity
recorded against both the indicator
microorganism and BST. Compound VD17529-111 was found to be active against BST
LC50 value of 4.75ug/ml (29-1). Also this
compound showed antioxidant property,
but inactive on the tested microorganism.
Compound VD17-529-185 showed activity
against BST,LC50 value of 1.10ug/ml(5-1) and
antioxidant property. This compound was
also found to be active against
Pseudomonas aeruginosa, Salmonella
species and candida albican,with zones of
inhibition of 6mm,7mmand 5mm
at100mg/ml respectively.
8.
HARAMI
MALGWI
ADAMU
PGS/97ISOLATION AND
98/402002 CHARACTECTERI
ZATION STUDIES
OF THE
BIOACTIVE
COMPOUNDS
FROM Ziziphus
mucronata (WILD)
DECEM
BER,
2006
Powdered samples (50g) each of the root and stem
This
plant
was
found
to
have
barks of Ziziphus muucronata were extracted using
hexane, acetone methanol and water respectively.
Phytochemical screening of the extracts revealed
antimicrobial
the presence of alkaloids, tannins, flavonoids,
activity and it is
saponins, terpenes cardiac and phenols.
recommended that
Antibacterial activity of these extracts showed that
they were very active against Pseudomonas
further work on
aeruginosa, Proteus mirabilis, Staphylococcus
the
aureus and Escherichia coli. Antifungal activities
components
active
that
against Trichophyton rubrum revealed that the rate
were not identified
of growth of the fungi reduced when compared to
the control.The methanol extracts of the plant parts
were tested in vivo for activities and were found to
be active in rats infected with Pseudomonas
aeruginosa mirabilis, Staphylococcus aureus and
Escherichia coli.
The feeding deterrent activity agaist cowpea
weevil (Callosobruchus mucutatus) was carried
and it was discovered that the methanol and
acetone extracts significantly deterred the weevil
from feeding on the cowpea. The acetone and
methanol extracts were purified using solvent
poarity partition extraction and the active fractions
further purified by column chromatography. Parts
of the crude extracts were also chemically
modified by actylation using acetic anhydride and
anhydrous zinc chloride.
The melting points of both purified and acetylated
products were determined.The acetone extract of
the stem bark of Ziziphus mucronata gave a
triterpenoid identified as 3B- hydroxyl-12-en-28-
should be isolated
and characterized.
oic acid (ursolic acid). Its structure was elucidated
by spectroscopic studies, including Ir,C13-nr,H-nmr
and mass spectrometry.
9.
JAURO
ALIYU
PGS/4020
38
GEOCHEMICAL
ANALYSIES OF
BENUE TROUGH
COAL EXTRACTS
AUGUS
T 2007
An azeotrope of dichloromethane and methanol (9: I)
was used to extract (soxhlct extraction) the powders of
various coal samples, secured from Lafia-Obi, Lamza,
Chikila, Kumo, Maiganga, Onyeama, and Doho, all of
the Benne trough. Samples of the extracts were
appropriately prepared and subjected to a number of
analyses. 'l'he GC-MS runs of the samples revealed a
range of saturated, unsaturated and aromatic
hydrocarbons. The Pristane/Phytane ratios and
odd-over-even
predominance
(OEP)
revealed that all the coals were
derived from a terrestrial source organic matter that
was deposited in dominant oxic envionment.
Vitriniet reflectance measurements of samples and
concentration assessments of steranes, hopanes and
phenanthrenes generally indicate a maturity trend in
the order, Lafia-Obi >Lamza - Chikila >Kumo Maiganga >Onyeama >Doho, with few exceptions
for coal samples. Both the calculated and the measured
vitrinite reflectances (Rc) place Lafia-Obi, Lamza and
Chikila samples in the bituminous coal rank, and the
others in this study are sub-bituminous. Increases in
the combined concentrations of naphthalenes and
phenanthrenes correlate well with rises in maturity.
Maceral composition, the free swelling index, sulfur
content, proximate analysis and vitrinite reflectance
clearly mark out Lafia-Obi sample as the better coking
coal of the lot. /\ number of the biomarker maturity
parameters and vitrinite reflectance measurements
place it at the peak oil window. The data from this
study point to immaturity and early maturity stages for
the other coal samples. Kerogen-typing based on
hydrogen indices and Pr/ nC17versus Ph/nC 18 plots
show that of the samples is of type Ill, with gas
generative potentials.
10.
PETER
MICHAEL
DASS
PGS/2002
/402060
BIODEGRADATIO
N STUDIES ON
POLYETHYLENE
WASTE (BAGS)
BY FUNGI
ISOLATED FROM
GROUNDNUT
SHELLS AND
RICE HUSKS
AUGUS
T 2008
Polyethylene (PE) degrading microbes were
screened from rice huske, groundnut shells or a
mixture of both by the enrichment culture method.
These microbes were identified as fungi belonging
to Aspergillus niger and Candida albicans. They
were used to study the degradation of polyethylene
films. The fungal viable count after 10-1 to 10-4
dilution gave 3.4 x 101 to 2.2 x 103 cfu/ml for
Candida albicans and 1.3 x 102 to 1.0 x 104cfu/ml for
Aspergillus niger. Test to monitor biodegradation
were optical density, liquid and soil burial. Optical
density test gave absorbance of 1.69, 1.2 and 1.15
for Translucent PE, Black PE and Striped PE films
respectively after 5th to 6th week of incubation when
Aspergillus niger were used. This signifies that
Aspergillus niger are predisposed to Translucent PE
rather than Black PE and Striped PE films. The
values of the absorbance for dumpsites films were
2.7, 2.21 and 2.17 for Translucent PE, Black PE and
Striped PE films (Figure 6). The acidity of the
biodegradation medium changes from slightly
alkaline
to
acidic.
Aspergillus niger gave a maximum pH of 4.8 for
Translucent PE film of Bauchi Plastic Company
(Figure 9) and 5.8 for dumpsites films. The tensile
strength measurement revealed the tensile strength
of BPC PE films to have decreased from an initial
1.1 Ncm-2, 1.16Ncm-2and 1.19Ncm-2 to 0.81 Ncm-2,
1.07Ncm-2and 1.11 Ncm-2for Translucent PE, Black
PE and Striped PE films respc ctively. Dumpsites
film gave change in film strength from initial 0.78
Ncm-2, 0.95 Ncm-2and 1.08 Ncm-2to 0.65 Ncm-2,
0.80 Ncrn" and 1.00 Ncm-2 for Translucent PE,
Black PE and Stripped PE films respectively. Also
polyethylene films exposed for weeks before'
inoculating with fungi gave a decrease in tensile
strength with increase in the incubation time. This
was ascribed to the erosion of the film by the
enzyme secreted by the fungi as they act on it to
produce metabolites consequently used as food. Soil
burial test did not give significant change in film
weight after 9 months of incubation. The
biodegradation test therefore revealed that the
transparent polyethylene bags were more susceptible
to biodegradation than the black and striped
coloured bags. This was attributed to the combine
effects of the presence of colourants (Table 6), and
the thickness of the films (Table 5). And Aspergillus
niger acted on PE films more than Candida
albicans. The Infra red spectra of films after 3 and 6
months of biodegradation gave absorption at
1720cm-1 corresponding to carbonyl group, 2900 2800 crn" due to methyl or methylene groups,
3700cm-1 due to hydroxyl groups and band at
1500cm- 1, 1340cm-1 and 1230cm-1 characteristics
df alkyl compounds in solid state. The
biodegradation of polyethylene bags was observed
to be as a result of the combined effects of photoand bio-degradation rearrangement of the
macromolecules. This has resulted in the formation
of alcoholic or hydro peroxide intermediates with
the subsequent dissociation of the chain. The
Wampler, 2004 mechanistic pathways was adopted
for the biodegradation of these films. The use of
transparent polyethylene bags if necessary should be
encouraged rather than the coloured ones because
they are easily biodegraded and contains little
amount of additives responsible for hazardous fumes
if burnt. However, biodegradable polyethylene bags
should be produced and utilized which would
gradually replace any other bags.
11.
BUBA
MAMMAN
WUFEM
PGS/
20002001/
402034
THE EFFECTS
OF CEMENT
DUST ON SOIL
MICRONUTRIE
NT METALS
JANU
ARY
2009
The effect of cement dust on cultivated soil
was studied by determining some available
micronutrient metal species and some
physicochemical parameters of soils and
cement dust using Atomic Absorption
Spectrophotometric technique and other
standard methods. Soil was collected from 015cm and 15-30cm depth of cultivated soil
around a cement factory and dust collected in
the field by allowing the dust to fall on the
collection sheet. The result of the
physicochemical analysis of soil showed a
mean pH of 6.76. The mean cation exchange
Excessive
dust
emissions
have
been
reduced
tremendously
recently, as a
result
of
installation of bag
filters;
reclamation of the
land
may
be
required.
Replacement of
excavated areas
with virgin soils
12.
ABBA
HAMZA
PGS/2001
2002/4020
42
PHOTOOXIDATIVE
DEGRADATION,
BIODEGRADATIO
DECEM
BER
2010
capacity and the organic carbon were 10.72
cmol/Kg and 1.88 g/Kg respectively. These
values are generally low because of low
biomass production, clay, and organic matter
content. The soil texture was sandy-clay. The
physicochemical parameters of the soil were
evaluated using the Limiting conditions and
Arithmetic modeling to assess the suitability
of the land for the growth of some
commonly cultivated crops. The mean
available micronutrient metals was found to
be 215.30 g/Kg Fe, 7.96 g/Kg Zn, 0.33 g/Kg
Cu, 80.79 g/Kg Mn, 2.05 g/Kg Ni, and 26.91
g/Kg Co. The metals were however found to
decrease with increasing distance away from
the factory and increasing depth of soil.
Chemical pools of the metals indicated that
the metals were distributed into six fractions
with most of the metals residing in the nonavailable fractions.
will help return
the
lands
back to the form
that can support
the growth of
plants. This will
help restore the
battered
microclimate of
the area. Planting
of trees may assist
in
the
rehabilitation of
the environment.
For
continuous
agricultural
activity around the
factory, safe zones
need
to
be
established
to
assist the fanners
grow their crops if
quality production
is to be achieved.
13 sets of 62 sample films of low-density
polyethylene
(LDPE),
high-density
polyethylene (HDPE), and propylene (PP) five
commercial, nine "pure"/additive-free and 48 filled
While
acknowledging the
modest scholarly
progress made in
N AND
STABILIZATION
STUDIES ON
LOW-DENSITY
POLYETHYLENE
(LDPE), HIGHDENSITY
POLYETHYLENE
(HDPE), AND
POLYPROPYLENE
(PP) FILMS.
with varying amounts of carbon black, starch, this work, the
butylated
hydroxytoluene
(BHT),
dilauryl following
thiodipropionate (DL TDP) and ferric stearate) were recommendations
prepared by compression moulding technique. Three are made in the
sets of the samples were exposed rooftop at 0°-, 45°- bid
towards
and 90°-Angle positions, one set was stored in a developing
refrigerator and another set stored in the dark at environmentally
room temperature for five years. Three sets of the degradable
samples were buried in soil at 5, 10 and 20 cm deep commodity
and another set placed in a desiccator and buried in thermoplastic
soil at 10 cm deep for five years. One set of the products:
remaining four sets was exposed to sunlight for one
year and buried in soil for four years, another set
was exposed for two years and buried for three 1. National
Agency for
years, another set was exposed for three years and
Food
and
buried for two years and the last set was exposed for
Drug
four years and buried for one year. Tensile strength,
Administrati
elongation- at-break, weight loss, and microbial
on
and
growth rating were determined on monthly and
Control
yearly bases to assess the extent of the samples'
(NAFDAC)
weatherability, biodegradability and stability. Visual
should,
as
examination of the samples was also comparatively
matter
of
carried out after each exposure and/or burial period.
urgent
From the results, progressive decrease in tensile
national
strength, elongation-at-break, and weight loss and
importance,
increase in microbial growth with increase in the
enforce the
time of exposure to sunlight and soil burial was
use
of
observed
for
all
the
sample
films.
environment
Resistance of the samples to photo-oxidative
friendly
degradation was found to follow the order: (BHT
(photoand DLTDP)-filled > BHT-filled > DLTDP-filled >
biodegradabl
carbon black-filled > commercial> unfilled> (carbon
e) plastics in
black, BHT and DLTDP)-filled > starch-filled>
packaging
(ferric stearate and starch)-filled > ferric stearate-
filled. Stabilizer efficiency against weathering
followed the order: BHT +DLTDP > BHT >
DLTDP
>
carbon
black
>
carbon
black+BHT+DLTDP. Except for the starch-filled,
the samples showed higher degree of degradation on
exposure to sunlight than in soil burial for the same
five-year study period. Combination of BHT and DL
TDP gave synergistic effect on the stability of the
samples towards photo-oxidative degradation.
However, when carbon black was added to BHT
and/or DLTDP, antagonistic effect was observed.
Additive effect was found in ferric stearate and
starch combination in both sunlight exposure and
soil burial tests. Very strong synergistic effect was
found to exist when biodegradation of the specimens
was preceded by photo-oxidative degradation.
Susceptibility of the samples to photo- oxidative
degradation was found to follow the order: HDPE «
LDPE < PP. This is ascribed to the higher
susceptibility to attack by oxygen of the tertiary
carbon atoms in PP and the presence of more branch
points in LDPE than in HDPE. Susceptibility to
biodegradation, however, was found to follow the
order: LDPE » HDPE > PP. This is attributed to the
morphology and molecular size of the samples.
LDPE, having higher branch points and less dense
than HDPE, is much more vulnerable to enzymatic
attack of the microorganisms than both HDPE and
PP. PP, having higher molecular size, is less
vulnerable
to
enzymatic
attack
of
the
microorganisms and hence it is relatively more
stable to biodegradation than both HDPE and LDPE.
Eight indigenous species of bacteria and nine
species of fungi were identified in the study, with
food
and
drinks ("pure
water")
sachets.
fungi being relatively more active in degrading the
sample films than bacteria.
13.
CHINDO
ISTIFANUS
YARKASUW
A
PGS/
19971998/
402011
PHYTOCHEMICA
L ANALYSIS OF
FICUS
PLATYPHYLLA
Del.-Holl(Moaceae)
14.
ETONIHU
ANAYO
CHRISTIAN
PGS/
20002001/
402036
CHEMICAL
ANALYSIS OF
SELECTED
NIGERIAN COALS
AND
COMBUSTION
AERODYNAMIC
EFFICIENCIES OF
BRIQUETTES
USING DESIGNED
AND
JULY,
2010
SEPTE
MBER,
2010
Air-dried pulverized bark sample of Ficus This plant has
platyphylla were sequentially solvent extracted been
reported
by polarity guided approach using both hot soxhlet (Abah et al, 2003)
and cold percolation methods. Ethanol gave the to have strong
highest percent recoveries of extracts, 37 % and CNS activity by
41.5 % for hot and cold extractions respectively. numerous
The least percent recoveries of 0.1 % and 1.5 % researchers. It is
were obtained for the hot and cold methods recommended that
respectively using toluene. Steroids, steroidal rings, further work on
terpenes as well as anthraquinones and resins were the
purification,
found present in the hexane hot and cold extracts. To pharmacological
aid isolation, alkylation, and hydrolysis reactions activity
and
were attempted on some of the extracts. Purification structural
was achieved through marginal solubility of the hot identification of
ethanol extract in hexane to obtain E-1. The IR, 1H other active pure
and 13C_NMR and GC-MS spectral analysis data compounds from
revealed E-l as 1, 4-dimethylbenzenedicarboxylic this
plant
be
acid ester.
carried out.
Outcrops of Nigerian coals Chikila (CKLI), Lamja
(LJC2), Lafia-Obi (LOC3), Jangwa (JC4),
Onyeama (ONC5), Okaba (OKC6) and Ezimo This research
(EZC8) were pulverized to 75um. Solvent extracts recommends
from benzene-methanol mixture (3: I) at 80"C. for the followings:
48
hrs
were
fractiol1ated
by column
I. That the Nigerian
chromatography using n-hexane, benzene, and
coal industry be
methanol elution. The n-hexane and benzene
revamped
fractions characterized by gas chromatography
immediately as the
contained CIO _ C20 series of n-alkanes with
coal mines have
pristane-phytane ratios from 1.32 to 2.20 and
undergone
a
FABRICATED
STOVES.
carbon preference index (CPI) values that ranged
from 0.98 (for LOC3) to 1.55 (for CKLI).
Polycyclic aromatic hydrocarbons in all samples
were naphthalene, phenanthrene and their methylsubstituted isomers, being highest in OKC6
(19.17%) and lowest in LJC (2.20%). The 1 R
spectra were similar for all samples with amide,
alkyne, cyanide, thiocyanate, and alkene absorption
bands. Proximate and ultimate analyses showed
that these coals ranked from ligniteous to
bituminous with highest percentage moisture,
volatile matter, and ash in CKLI. Percent total
sulphur (daf) was highest in LOC3 (1.75), while %
N (dal) was highest in ONC5 (1.95). 0.2 kg
briquettes of different fuels loaded into uniform
stoves of different aperture sizes was used to
determine
cfficiency of
the
combustion
aerodynamics by both the Boiling Test and
Constant
Heating
methods.
The time taken to boil 2 liters of water varied
sisniftcantly from 26 to 12 minutes (for sawdust)
and 29 to 13 minutes (for rice husk) briquettes,
when aperture size increased from 5 to 15 mm.
With sawdust briquelles, efficiencies increased
from 26.20 to 35.60% (for Boiling Test) and 7.58
to 8.89% (for Constant Heating), as stove aperture
size increased. For rice husk briquettes, efficiency
increased from 26.02 to 34.55% (for Boiling Test)
and 8.15 to 9.32% (for Constant Heating). No
significant change in efflciencics was noted
between the square-shape stove C and the roundshape stove D for the same fuel type.
protracted
deterioration and
brigands
have
almost taken over
the
mmcs.
2. That
more
resources be
invested in
coal research
and
technology
in order to
diversify
the
national economy
through
an
efficient
coal
utilization.
The shape of
aperture of
combustion
stoves could
be
investigated
to determine
its
impact
or
otherwise on
stove
burning
efficiency.
15.
ABAYEH,
PGS/
OLUWAKEM 2002- 03/
I MODUPE
402065
BIODIESEL
PRODUCTION
FROM Luffa
aegyptiaca SEED
OIL
JANUA
RY,
2011
In this research, Luffa aegyptiaca seed oil was
extracted with hexane or petroleum ether and the
oil quality parameters determined. The oil yield
was 19-25%, moisture content 4.6%, iodine value
130%, acid value 20.62%, saponification value
l68mgKOH, peroxide value 280meq/kg, free fatty
acid 10.36%, density 0.9lgm-3 and specific gravity
0.92. Based on the iodine value, LS0 is a semi
drying oil containing 50 - 80% linoleic acid, with
18 Carbon atoms and 2 double bonds. The methyl,
ethyl and isopropyl esters of LSO were prepared
through a base (KOH) catalysed transesterification
process and their fuel quality parameters
determined; these compared favourably to that of
diesel fuel, D2 which served as control. The fuel
properties of the alkyl esters also compared
favorably to literature data for soy oil methyl ester
(SME) and sunflower oil methyl ester (SUME).
The fuel properties- density, flash point, pour
point, cloud point, kinematic viscosity and cetane
number for the biodiesels from LSO were
determined and are as listed for Luffa seed oil
methyl ester(LOME), Luffa seed oil ethyl ester
(LOEE) and Luffa seed oil isopropyl ester (LOISE)
respectively: density (0.75g/cm3, 0.79g/cm3and
0.82g/cm3), flash point (162oC, 140°C and 1380 C)
pour point (-5°C, -9°C and 5°C) cloud point (-3°C,
-7°C and 80C) kinematic viscosity (1.49mm2/s,
It will be quite
rewarding for future
researchers in this
area to devise a
means of dehulling
the seed, a removal
of the hard black
seed coat will lead to
an increase in oil
yield. Iition to other
qualities
already
highlighted, this will
enhance
the
suitability of this
plant iodiesel feed
stock. Biodiesel as a
fuel has advantages
over
petro-diesel
which include.
It is therefore
recommended that
further research be
directed at
 Collecting
the seeds
as soon as
it matures,
but
just
before the
1.68mm2/s and 1. 74mm2/s), cetane number
(40.8oC, 41.8oC and 42.30C). The values obtained
for the biodiesels for these parameters conform to
specifications of the US ASTM D 6751 and the EU
EN 14214 for biodiesels. The energy content of the
biodiesels was also determined via calculation as
Higher Heating Value (HHV) and from experiment
as calorific value. The HHV for the LSO and its
biodiesels - LOME, LOEE and LOISE were
40.6MJ/kg, 41.75MJ/kg, 41.83MJlkg and 42.
14MJlkg. The calorific values in Joules (1) were
858.33,
1103.56,
1230.42
and
1307.92
respectively; the value for petro-diesel D2 was
1348.80J. Corrosion tests were conducted on the
biodiesels and they were found to be non corrosive.
The Na and K content of the LSO and alkyl esters
was also carried out and found to fall within the
accepted limit of 5ppm for Na and K combined.
Other metals analysed for are Co, Cu, Fe, Mn, Pb
and Zn; their values lie within the range 0.003 1.465 ppm. The study has shown that the three
alkyl esters from Luffa aegyptiaca seed oil can be
used as biodiesels.
16.
EJILA
AMALI
PGS/
20012002/
402043
SYNTHESIS,
CHARACTERISAT
ION AND
APPLICATION OF
STYRENE-COEPOXIDISED
MAY,
2011
Triglyceride based functionalised copolymers for
improved water resistance and other surface
coating properties were synthesised by free radical
emulsion polymerisation of styrene and epoxidised
rubber seed oil (ERSO) monomers using potassium
persulphate (K2S208) initiator, and non-ionic
emulsifier at 65 -75°C under nitrogen gas. The
back
begins to
dry up and
turn brown;
this
may
increase
the
oil
yield
Further study on the
influence of surface
coating formulation
and curing conditions
on the mechanical and
rheological properties
copolymer latexes
were characterised,
formulated
and
applied
on
leather to assess the surface coating properties. The
copolymers are polyhydric (polyol) resulting from
the cleavage of epoxide rings, termination of the
propagating chain with hydroxy ether radical from
an epoxide cleavage and reduction of carbonyl
group. The copolymers were of good yield with
moderate
low
molecular
weights
and
having Mark - Houwinks constants of K = -3.73 x
10'5 dl/g and 'a' = 0.98 for the copolymer
homologous series. The lacquer emulsion for the
surface coatings were formulated with the
copolymer latex and the polyurethane film formed
after cross- linking with isocyanate on application
to leather was evaluated for surface coating
properties by distension of the grain, grain crack
strength and water vapour permeability. The crosslinked application of the copolymer latex with
isocyanate increased the grain crack distension
(R2= 0.953, and 0.761 with 0.23 g and 0.27g
isocyanate respectively) and water vapour
permeability (R2= 0.748) of the leather due to the
reinforcement of the film by polyurethane bonding.
The formulations were found to have very good
film properties and suitable for most leather
finishing properties especially flexible - high
impact and chemically resistant polyurethane
(PUR) patent, transfer-coated, impregnated
corrected grain and full grain water repellent
leathers.
RUBBER SEED
OIL FOR
SURFACE
COATING ON
LEATHER
17.
KOLO
PGS/01-
KINETICS AND
2011
The kinetics and thermodynamics of corrosion
of the copolymer is
important for process
optimisation.
Study
on
the
impregnation
and
cross-linking of the
copolymer latex for
improved shrinkage
temperature,
and
surface
coating
properties of collagen
substrate.
The
surface
coating copolymer
is recommended
for waterproofing
of sole leathers
and the production
of
wet
look
leathers of natural
grain character.
18.
ALHAJI
MODU
02/402039 THERMODYNAMI
CS OF
CORROSION
INHIBITION OF
MILD CARBON
STEEL IN ACIDIC
MEDIUM BY
COLA NUT SEEDS
EXTRACT
AYENI
NURUDEEN
AFOLAMI
PGS/01EFFECTS OF DYE- 2011
02/402076 RESIN
COMPLEXATION
ON FLAME
RETARDANT AND
DYEING
PROPERTIES OF
CELLULOSIC
FIBER
inhibition of cola nut seeds extract on mild carbon
steel in acidic medium has been studied using
weight loss corrosion measurement technique at
30-40°C. The result showed that the weight loss
and corrosion rates were found to decrease with
increase in the concentration of inhibitors and also
time of immersion. The inhibition efficiencies and
degree of surface coverage of adsorbed inhibitors
were evaluated. Cola acuminata gave the highest
percentage inhibition of 68.64% than cola nitida
and garcinia cola (60.27% and 34.08%
respectively). The inhibition efficiency was higher
at lower temperature suggesting a physical
adsorption mechanism. The results of the study
followed both Langmuir and Frumkin adsorption
isotherm models while the Flory-Huggins isotherm
was not obeyed. The kinetics and thermodynamic
parameters have been evaluated and the results
confirmed that the adsorption process is
exothermic, reversible, spontaneous and feasible.
Methylolmelamine with various degree of
substitution were synthesized by reacting I mole of
melamine (126g/mol.) each with different moles of
38% formaldehyde. The reaction produces
dimethylol melamine, trimethylol melamine,
tetramethylol melamine, pentamethylol melamine
and hexamethylol melamine (coded MR2, MR3,
M~,
MRs
and
MR6
respectively).
Similarly, monomethylol melamine phosphate,
dimethylol melamine phosphate, trimethylol
melamine phosphate and tetramethylol melamine
phosphate (coded MPR1, MPR2, MPR3and MP~
respectively) were prepared reacting 1 mole of
Melamine phosphate (MP) (224g/mol.) with
various moles of 38% formaldehyde. These
prepolymers were characterized using IR
spectrophotometer and viscometry measurement,
used to resinate purified cotton fiber at varying
curing
temperatures,
curing
time
and
concentrations, and then subsequently dyed with
procion blue MX-R. Flame propagation rate,
thermogravimetry studies, measurement of loss in
strength, gain in crease recovery of the resinated
fiber and % exhaustion of the dye were carried out.
Flame propagation rate of the fiber was reduced by
36% when resinated with 15% MR6 and cured at
100°C for 15 minutes and reduced by 45% with
MPR4
under
the
same
condition.
Thermogravimetry
results
indicated
first
degradation in mass at 250°C of fiber resinated
with MR series while fiber resinated with MPR
series showed first degradation at 200°C. The
highest degree of dye exhaustion was obtained at
40°C for both pure and resinated fibers. Percentage
dye
uptake
and
affinity
determined
spectrophotometrically and thermodynamically
respectively showed marked improvement.
Fastness properties determined showed a relatively
higher stability of the dyed materials.
19.
BORYO
DORIS
EZEKIEL
AMIN
PGS/
20012002/
402047
SOME EFFECTS
MAY,
OF ALTERNATIVE 2011
CHEMICAL
TREATMENTS ON
THE
MECHANICAL
AND DYEING
PROPERTIES OF
The demand for NaOH is high because of its numerous
applications like in scouring and mercerization
processes, thereby making it scarce and costly. This
highly alkaline NaOH attacks the textile material if not
properly handled leading to reduction in mechanical
and dyeing properties of the fabric. The effluents of
these processes are corrosive and harmful to the
environment too. This study was concerned with
Further
study
could be carried
out on the X-ray
diffraction
analysis of the
Scoured
and
Mercerized fabrics
treated with the
COTTON/POLYES
TER BLEND
FABRIC
sourcing for suitable and reliable, safe and cheap
alternative scouring and mercerizing agents that may
improve the mechanical and dyeing properties of cotton
polyester blend fabric. The water imbibing property of
the treated fabric and the PH of the used liquor were
evaluated. Cost analyses tor the agents were
investigated. Six alternative 1-5% scouring and 19-23
% mercerizing agents were used [namely liquid NH3,
NH4OH, (NH4)2C2O4 CH3CH2OH, CH3COOH, (COOH)2
and NaOH as the control) before and after bleaching
the fabric respectively. The optimum experimental
results showed that the fabric treated with alternative
scouring and mercerizing agents improved the
mechanical and dyeing properties better than the
control. 3% liquid NH3, 2% NH4OH, 3% CH3COOH
and 3% liquid NH3, as alternative scouring agents
recorded the optimum breaking load (13.11 kg),
breaking extension(14.14%) linear density (6.327 Tex)
and dry crease recovery (106°) rcspctively more than
NaOH. 2% liquid NH3treated fabric recorded 86.8%
percentage exhaustion as the optimum. For washfastness, four alternative scouring agents strongly
competed at various concentrations with the control
which revealed an optimum ranking of 5 (excellent
wash-fastness). 4% (NH4)2C2O4 Scoured fabrics
recorded the highest water or imbibitions (2.9g). The
optimum experimental results for the mercerizing
agents showed that 19% NH4OH optimally improved
the breaking load (16.19kgf) more than the control.
The optimum value for breaking extension (24.98%) of
the mercerized fabric was by 19% (NH4)2C2O4
ranking the highest. 19% CH3CH2OH mercerized
fabric recorded the highest linear density (4.6904 tex).
alternative agents.
21% NH4OH mercerized fabric ranked the highest for
dry crease recovery (132°). 22% (NH4)2 C2O4
mercerized fabric displayed the optimum value for the
percentage exhaustion of indigo dye (85.7%). The
wash-fastness is another interesting result where all the
mercerizing agents at their optimum gave a grey scale
rating of 5(excellent wash-fastness). The water
imbibing abilities of the various fabrics mercerized with
the agents showed a competing range between 2.22.5g.The alkalinity and acidity (pH) of the alternative
agents after the scouring and mercerizing processes
were environmentally friendly in comparison with the
highly akaline NaOH (pH range of 10.30-12.30), hence
unfriendly. The cost analysis revealed some of the
alternative agents far cheaper than the NaOH. These
imply that the alternative agellts are suitable and reliable
as scouring and mercerizing agents better than NaOH.
Therefore the alternative agents could be employed in
the Textile lndustry and commercially as scouring and
mercerizing agents so that the world could be a better
and safe place for everbody.
20.
AKPOMIE
TIMOTHY
MARHIERE
PGS/
20062007/
4020108
SIMULATION
ANALYSIS OF THE
BIODEGRADATION
AND
BIOACCUMULATION
OF SOME
ENVIRONMENTAL
SAMPLES AND DATA
(SOIL, WATER AND
FOOD) FROM
BAUCHI, JOS AND
KANO METROPOLIS
NIGERIA.
APRIL,
2013
This study was carried out in order to develop
suitable computer generated mathematical models
for forecasting the concentration of iron (Fe),
cadmium (Cd), Zinc (Zn), Copper (Cu) and Lead
(Pb) from pollution studies in water, soil and food
samples in several areas of Jos metropolis as well
as some observed results of pollution studies from
Bauchi and Kano States. The quantitative
determination of the concentrations of these metals
was carried out using the Atomic Absorption
spectrometry. The concentrations obtained in each
Further research is
also suggested for
the determination
of an appropriate
model for the
degradation
of
herbicides in soil.
The modeling of
the
temperature
and
time
dependent models
set of analysis, including the observed results, were
then modelled using the Minitab computerinstalled software. Several time-series and
multiple-regression models of two and three
independent variables (pH, temperature and time)
for each set of analysis were developed. These
models were expressed as Y = a + b*t - ct2
(quadratic model) for the time-series and Y = B0 +
B1 (PH)+B2(Temperature), for the pH and
temperature-dependent models. These models were
validated by comparing them to those obtained
from the least square method. The developed
model on the degradation of herbicides in soil, that
is, Atrazine Concentration (ppm) = - 24.3 +
0.113 Time (min) + 0.226 pH + 0.307 Tempt
(OC) could not be validated statistically, however,
it was remarkable. The models for percentage
recovery or percentage degradation of Ascorbic
acid
content
in
various
fruits
and
milk products, were all found to be of simple
linear, quadratic or cubic regression models with
either the temperature or the storage time ( days) as
the independent variable, and the order for
credibility was cubic> quadratic> linear. Finally,
these models gave an insight on the forecast and
predictability of some of the pollution indices in
water, soil and food systems.
21.
GUSHIT
JOHN
STEPHEN
PGS/
20092010/
4020120
THE RISK
ASSESSMENT OF
HERBICIDES
USAGE,
DETERMINATION
AND
FEBRU
ARY,
2014
(multi-linear
models) on the
percentages
recovery
of
ascorbic acid in
various
fruits
should also be
investigated.
This research involves the risk assessment of the Suggestion for further
utilization, determination and the remediation of studies
herbicides residues in Plateau State for two seasons
starting in June 2010 to June 2012. The risk Emphasis should be
assessment was carried out through a field survey of laid
on
finding
herbicides usage by farmers, marketers and
REMEDIATION OF
THEIR RESIDUES
IN SOIL, WATER
AND CROPS IN
PLATEAU STATE,
NIGERIA.
agricultural extension workers (AEWs) using semistructured questionnaires. The parameters of interest
captured in the field survey are: assessment of the
understanding of the stakeholders on the toxicity of
the herbicides, precautions taken and basic health
symptoms experienced on exposure to the
herbicides. From the survey, five (5) herbicides
which include: atrazine, paraquat, glyphosate, 2, 4dichlorophenoxy acetic acid and pendimethalin are
the most frequently used within the study area. Low
level of awareness of stakeholders on the risk
involved on exposure to these chemical substances
was identified as a major factor that could influence
the risk of the herbicides usage. The standards which
were prepared from the commercial brands of
frequently used herbicides within the study area
were prepared by extraction, crystallization and
recrystallization with the aid of various solvents
(chloroform, methanol, acetone etc) depending on
the properties of the herbicides. The standards
obtained were used for the GCIMS determination of
the herbicide residues in the extracts of the various
systematically sampled products of interest obtained
within
the
study area
which
includes:
soil, water, ground nut, rice straw, cucumber and
potatoes. Atrazine, 2,4-D and their corresponding
derivatives were found in most of the sectors and
products analysed. To remediate water systems
already contaminated with the atrazine, readily
available and cheap waste plants materials which
include; acha husk charcoal (AHC), acha husk
charcoal and cocoyam leave/stem blended with
pulverized kaolinitic clay (<2mm) designated as
AHC-CB and CLC-CB respectively were used to
locally
available
materials for use to
remediate
the
life-threatening
pollutants from the
environment.
Researches should be
carried out with a
view to exploring the
potency and potential
of
some plant based and
natural
materials
which
were
historically used as
pesticides
in
various
capacities
within
our
communities.
remediate the atrazine contaminated water using the
adsorption technique. The order of efficiency of
adsorption of the materials used when compared
with commercial adsorbent is; M&B activated
charcoal>AHC>CLC-CB>AHC-CB.
Awareness
creation on the toxic nature of herbicides being used,
appropriate legislation and creating a sustainable
help desk, form part of the conclusion and
recommendations suggested in this work.
22.
IYUN
OGUNKEMI
RISIKAT
AGBEKE
PGS/
20092010/
4020117
SYNTHESES OF
DISPERSE DYRES
DERIVED FROM
THIOPHENE AND
THEIR
APPLICATION ON
POLYESTER AND
NYLON FABRICS
FEBRU
ARY,
2014
The first step in this work is the synthesis of the dye
intermediates from ethylacetoacetate, malononitrile,
ethylcyanoacetate,
morpholine,
4chloroacetoacetanilide, methylcyanoacetate, N-(2,4dimethyl)-3-oxobutyramide and sulphur. Six diazo
components and thirteen coupling components were
synthesized. The intermediates were diazotized
respectively using nitrosylsulphuric acid method at 05°C. The diazonium liquors were coupled immediately
with various synthesized coupling components such as
N-phenylmaleirnide, 2-nitro-N- phenylmaleimide, 3nitro-N-phenylmaleimide, 2-chloro-N-phenylmaleimide,
3-chloro-Nphenylmaleimide,
2-methoxyNphenylmaleimide, 2-methyl- N -phenylmaleimide,6hydroxy-4-methyl-2-oxo-1,2-dihydropyridine-3carbonitrile, I-butyl-6-hydroxy-4-methyl-2-oxo-1, 2dihydropyridine-3-carbonitrile to produce seventy three
dyes of diverse colours. The various intermediates and
the novel dyes produced were characterized by
determining
the
melting
points, infrared (lR), nuclear magnetic resonance (NMR)
23.
MOOREY
BINBUT
DALEN
PGS/
20092010/
4020115
LOCAL CONTENT
DEVELOPMENT
FOR RAW
MATERIALS
USED IN THE
COMMERCIAL
MUNUFACTURE
OF URETHANE
FOAMS
APRIL,
2014
spectroscopies, gas chromatography/mass (GC/MS)
spectroscopy. In addition Uv-visible studies of these
dyes in a number of polar solvents showed a
considerable difference in Amax The introduction of
various substituents to these azo dyes as well as the
polarity of solvents used resulted in absorption in the
visible region ranging from 403 to 672nm. The value of
the logarithm of the molar extinction coefficient (logs )
of the dyes were in the range of 5.00 to 5.92 indicating
their good intensity of absorption. These dyes were
applied at 2% depth on nylon and 4% depth on polyester
fabrics and gave bright yellow, brown to maroon colour
hues with very good depth and levelness on the fabrics.
The percentage exhaustion of the dye bath was found to
be very good (some are up to 100%). The dyed fabrics
showed good to excellent (4-5) wash fastness,
sublimation, rubbing, perspiration fastness and fair
lightfastness properties.
This research explores and exploits alternative 1. Further studies
non-conventional and supplement local sources of should be carried out
raw naterials which includes castor oil (CO), to identify other
or
kaolin and chlorinated castor. Oil (CCO) in foam substitute
supplement
manufacture. CO was characterized for physicolocal raw materials
chemical properties and results obtained are within
for other chemicals
the American Standards for Testing of Materials
used in the foam
(ASTMD 1639-90,1994) specifications which industry in Nigeria
include; Bpt (220 0C), AV (3.16mgKOH/g), HV especially
TDI,
(161.42mgKOH/g) and IV (83.75g I2/l00g ). IR dimethyl
spectral analysis of the oil shows characteristic ethanolamine
and
absorption bands of hydroxyl (critical in foam stannous octanoate
manufacture), carbonyl and olefinic groups which 2. Blending of CaC03
compare reasonably with those of conventional
(CPO) and polymer (PPO) polyols. Foam
formulations based on CO blends with the polyols
were investigated for density, tensile strength,
elongation at break, compression set, and creep
recovery variations. The results showed a critical
blend composition for both polyols at PO/CO
(90%: 10%) which displays higher mechanical
properties compared to other blend compositions
and over and above 100% PO. Tensile strength at
CPO/CO (90%:10%) displayed a value of
11.06N/cm2 as against 6.81 N/cm2 at 100%CPO,
while PPO/CO (90%:10%) indicates 9.49 N/cm2
as against 6.03 N/cm2 at lOO%PPO. Similarly,
values for elongations at break, indicate 49.99mm
at CPO/CO (90%:10%) as against 73.98mm for
100%CPO, while at PPO/CO (90%:10%), the
value was 37.05mm compared to 44.75mm for
100%PPO while 100% CO shows a low tensile
strength of 2.04 N/cm2 and elongation at break of
9.95mm. Furthermore, results of creep recovery
indicate a value of 30.21% at CPO/CO (90%:10%)
compared to 21.52% at 100% CPO, while the
corresponding value for PPO/CO (90%:10%) was
25.49% as against 14.65% for 100%PPO. Similar
trends were observed for mechanical testing of
factory trials of Iso-block foams. CPO and PPO
exotherms monitored as temperature rises for foam
formulations with variations in blow index
indicates that as the blow index increases, T1 and
IT2 increases for both polyols far above the
and
kaolin
to
determine optimum
levels
of
performances
on
curing times and
physico-mechanical
properties in foam
formulations.
3. Exotherms studies
should be monitored
for kaolin filled
foam formulation.'
4. Isolation
and
purification
of
ricinoleic acid, the
main fatty acid of
castor
oil
triglyceride, for use
in
foam
manufacture.
5. Other clays such as
bentonite,
fullers
earth, etc should be
tried as fillers for
formulations.
6.
Non-edible
vegetables such as
jatropa oil, ben oil,
etc
should
be
modified
as
substitutes for CPO,
PPO
and
Polysilicone
acceptable temperature range of 22-26oC for foam
manufacture. Also commercial kaolin,(Al2 Si2 O5
(OH)4), a clay mineral was characterized for
moisture content (= 1.30%), sieved particle size (=
l50um) and Apparent Bulk Density,ABD (=
0.40g/cm3) and compared to CaC03, a
conventional filler use extensively by the foam
industry in Nigeria, showed a moisture content of
0.60%, sieved particle size (= l50um) and ABD (=
0.75g/cm3. Foam formulations based on variations
of kaolin and CaC03 filler loading with polyols
were investigated for curing times, density, and
elongation at break, tensile strength, compression
set, and creep recovery. The results showed that
curing times decrease immediately after cream
times for both fillers. However, the rate of curing
is faster for kaolin than CaC03 filled foams. It
was also observed generally that % free isocyanate
content increases with filler loading which
indicates that fillers prolong curing times;
however, this delay is more pronounced for CaC03
than kaolin. This indicates that polymerization is
usually incomplete because of the active
isocyanate groups still present after aging. Results
of tensile strength indicate that filled foams
display peak values of 73.87 N/mm2 at 12g kaolin
and 73.89N/mm2 at 8g CaC03 for PPO
formulations, while CPO displays peak values of
141.6813N/mm2, 142.13N/mm2 and 141.80
N/mm2 at 2g and 4g kaolin and at 6g CaC03 in that
order. Chlorinated castor oil (CCO) fire retardant
surfactant
as
lubricant.
7. Other inorganic fire
retardants such as
Mg(OH)2, AI(OH) 3,
borax, NH4Cl etc
should be tried in
foam formulation.
properties were compared with dichloromethane
(MC) and Sb203 and their blends on flexible
polyurethane foam samples. The results show that
burning rate decreases with increase in mass of
fire retardant for all the formulations in the order;
CCO > Sb203> MC.
Emphasis should be
laid on finding
locally
available
materials for use to
remediate the lifethreatening
pollutants from the
environment.
Researches should
be carried out with
a view to exploring
the potency and
potential of some
plant based and
natural
materials
which
were
historically used as
pesticides in various
capacities
within
our communities.