Research Journal of Chemical Sciences 
______
______________________________
______
____
 
ISSN 2231
-
606X
 
 
 
Vol. 
2
(
5
), 
51
-
56
, 
May 
(201
2
)
 
 
Res.J.Chem.Sci.
 
 
 
International Science Congress Association
 
 
 
 
    
51
 
Corrosion Inhibition of Mild Steel by Alkaloid Extract of 
Ocimum Sanctum
 
in HCl and HNO
3
 
Solution
 
 
Nutan Kumpawat, Alok Chaturvedi *
 
and
 
R.K. Upadhyay
 
Synthetic and Surface Science Laboratory, Department of Chemistry, 
Govt. College, Ajmer
,
 
Raj., INDIA
 
 
 
Available online at: 
www.isca.in
 
(Received
 
 
6
th
 
March 
201
2
, revised
 
25
th
 
March 
 
201
2
, accepted
 
5
th
 
April
 
201
2
)
 
 
 
 
 
 
Abstract
 
Corrosion of mild steel in hydrochloric and nitric acid solution was studied by weight loss and thermometric methods in 
presence of ocimum sanctum extract. From weight loss data it was observed that the inhibition efficiency increases with the 
inc
reases in the concentration of the extract of stem in HCl and 
HNO
3
 
solution as compare to extract of leaves of ocimum 
sanctum. Maximum inhibition efficiency was found (98.67%) in 0.5N HCl acid with 1.2% stem extract, whereas it was (71.62%) 
in 2N HNO
3
 
acid with same concentration i.e. 1.2%. The corrosion rate was found to decrease with the increases in 
concentration of extract up to 0.3% to 1.2%. In the case of thermometric method it was observed that the reaction number 
decreases with the increases in
 
the concentration of extract while inhibition efficiency increases with increasing concentration 
of extract of ocimum sanctum in 
HCl and 
HNO
3
 
solution.
 
 
Keywords:
 
Ocimum sanctum, corrosion inhibition, reaction number, weight loss, surface coverage.
 
 
 
Introduction
 
Mild steel is widely used for mechanical and structural 
engineering purpose, boiler, plates, steam engine parts and 
automobile etc. it finds a variety of uses in most of chemical 
industries due to its low cost and easy availabi
lity for fabrication 
of various reaction vessel, tanks and pipes etc. In acidic medium 
metal tends to corrode. HCl and HNO
3
 
acids have been used for 
drilling operation.
 
 
The present study is based on the fact that some nitrogen and 
sulphur containing natur
al products like Tarmerind tea leaves, 
Beet root
1
-
2
, Saponin
3
, Terminalia bellerica
4
, Oxandra asbeckii
5
, 
Argemone mexicana
6
, Betanin
7
, Henna
8
, Wheat
9
, Ginger
10
, 
Marraya koeningii
11
, Garlic extract
12
, Ananas sativum
13
 
have 
been found effective corrosion inhibitors for mild steel.
 
 
The importance of the study lies in the fact that naturally 
occurring plant products are non
-
polluting, ecofriendly, less 
expensive, less toxic and easily available. They are 
biodegradable so
 
can widely be used without side effect.
 
 
Various heterocyclic compounds synthesized in laboratory 
14
-
18
 
having heteroatom O, N and S are found to have higher basicity 
and electron density thud assist corrosion inhibition. N, O and S 
are active centre for 
the process of absorption on the metal 
surface. The electric charge, orientation, shape and size of the 
molecule play an important role in the effectiveness of 
inhibition. They are used as corrosion inhibitor since they are 
get adsorbed on the metal surfac
e which essentially block the 
discharge of H
+
 
and dissolution of metal ion in acidic 
environment, the extract of different parts of plant like seeds, 
stem, bark and leaves can be used as inhibitor to reduce the 
corrosion rate of mild steel.
 
 
Ocimum sanctum
 
is a very common plant in Indian system, 
which has been used as antimaterial and antibacterial, air 
purifier from ancient time in Indian omes. It’s stem and leaves 
powders are used as medicine in many diseases viz. useful in 
blood glucose management, mai
ntain a healthy digestive 
system, encourage efficient use of oxygen, enhance the efficacy 
of many therapeutic treatments etc.
 
 
The chemical composition of ocimum sanctum is highly 
complex, containing many vitamins like A and C, calcium, zinc, 
iron, chlorop
hyll and many other phytonutrients are present in 
extract of ocimum sanctum.
 
 
Major chemical constituents responsible for physico
-
chemical 
action of  ocimum sanctum are volatile oil (0.1 to 0.9% ), 
eugenol (60
-
70%), cavacrol (about 3.0%), eugenol methyl et
her 
(20%) and other minor chemical constituents of ocimum 
sanctum are alkaloids, glycoside, saponin, tannin, maleic acid, 
ursolic acid, citric acid and tartaric acid.
 
 
 
 
 
 
                    
 
 
 
Eugenol
 
 
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ISSN 2231
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606X
 
 
Vol. 
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-
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Res.J.Chem.Sci
 
International Science Congress Association
 
 
52
 
 
 
                                                                                              
 
 
 
Ursolic Acid
 
 
β
-
bisabolene (13
-
20%), methyl chavicol (3
-
19%), 1
-
8 cineole 
(9
-
33%), α
-
 
bisabolene (4
-
7%),  α
-
 
terpineol (1.7
-
7%), 
campestrol, cholesterol, stigm
a sterol,  β
-
 
sisterol and methyl 
ester of common fatty acid were the main constituents of the oil 
during observation period. In continuation to our earlier 
investigation
19
-
20
 
on mild steel in acid media with extract of 
ocimum sanctum as corrosion inhibito
r the present work deals 
with corrosion inhibition of mild steel by alkaloid of ocimum 
sanctum in HCl and HNO
3.
 
 
Material and Methods 
 
The mild steel, which was used for the experiment having 
elemental composition: Fe 98.5%, carbon 1
-
2%, manganese 0.1
-
0.2%, phosphorus 0.4
-
0.5% and sulphur 0.02
-
0.03%. Specimens 
were prepared by cutting the mild steel into square shaped 
pieces having dimens
ion of 2.0cm � 2.0cm� 0.03cm with a 
small hole of about 2 mm diameter near the upper edge.  
Specimens were polished to mirror finish by using emery paper. 
The
 
extract of stem and leaves of o
cimum sanctum obtained by 
refluxing the dried leaves and stem in s
oxhlet in ethanol by 
heated at about 80hrs. The solution of HCl and HNO
3
 
were 
prepared by using double distilled water. All chemicals used 
were of AR grade. Solution of different concentration of extract 
was prepared in ethanol. 
 
 
Each specimen was suspend
ed by a V shaped glass hook made 
of capillary and plunge into a beaker containing 50mL of the 
test solution at room temperature, after the sufficient exposure, 
test specimens were washed with running water. Duplicate 
experiments were performed in each case
 
and mean value of 
weight loss was determined. The percentage inhibition 
efficiency was calculated as 
21
.
 
 

% = 100 (

W
u
 
-
 

W
i
)/

W
u
 
 
Where 

W
u
 
and 

W
i
 
are the weight loss of the metal in 
uninhibited and inhibited solution, respectively. The degree of 
surfa
ce coverage (

) was calculated as
22
.
 
 

 
= (

W
u
 
-
 

W
i
)/ 

W
u
 
 
Inhibition efficiency was also determined by thermometric 
method. The specimen was plunge into test solution and initial 
temperature was noted. As soon as the reaction started 
temperature increased slowly at first, then rapidly and achieved 
a maximum value
 
before falling. The maximum temperature 
was noted. Percentage inhibition efficiencies were calculated as 
 
 

% = 100 (RN
f
 
–
 
RN
i
)/RN
f
 
 
Where RN
f
 
and RN
i
 
are the reaction number in the free solution 
and in presence of inhibitor. RN is defined as 
–
 
 
 
RN = (T
m
-
T
i
)/t
 
 
Where T
m
 
and T
i
 
are maximum and initial temperature, 
respectively and t is the time in minutes required to attain 
maximum temperature. The corrosion rate (CR) in mm/yr can 
be obtained by the following equation
23
.
 
                                   
                                    

W � 87.6
 
                      
Corrosion rate (mm/yr) =       





 
                                                                      
A � T � d
 
 
Where, 

m is weight loss in mg, A is area of specimen in cm
2
, 
T is 
time of exposure in hours, d is density of metal in gm/cm
3
.
 
 
Results and Discussion
 
Weight loss data, percentage inhibition efficiency, corrosion 
rate and surface coverage for different concentration of HCl
 
and 
HNO
3
 
solution with different concentration of
 
inhibitor are 
given 
t
a
ble
-
1. It is observed from the t
able 1 that inhibition 
efficiency decreases with increasing strength of HCl solution 
and inhibition efficiency increases with increasing concentration 
of extract in each strength of acid solution. The 
maximum 
efficiency has been observed in lowest acid concentration i.e. 
0.5N HCl acid with highest concentration of inhibitor i.e. 1.2% 
(98.67%) for stem extract. Whereas it is (96.02%) for leaves 
extract in same HCl concentration. The corrosion rate has be
en 
observed maximum in bark solution and it decreases with the 
increasing concentration of inhibitor in HCl solution of different 
strength. Corresponding variation of inhibition efficiencies with 
concentration of inhibitor are shown in fig
ure 
1 for differe
nt 
concentration of HCl solution.
 
 
Table 2 shows results of HNO
3
 
solution. From the table it is 
observed that inhibition efficiency increases with increasing 
strength of HNO
3
 
solution and it also increases with increasing 
concentration of extract in each s
trength of acid solution. The 
maximum inhibition efficiency has been observed in highest 
acid concentration i.e. 2N HNO
3
 
with highest concentration of 
inhibitor i.e. 1.2% (71.62%) for stem extract, whereas it is 
(59.04%) for leaves extract in same acid con
centration. The 
corrosion rate has been observed maximum in blank solution 
and it decreases with increasing concentration of inhibitor in 
HNO
3
 
solution of different strength. Corresponding variation of 
inhibition efficiencies with concentration of inhibito
r are shown 
in fig
ure
 
2 for different concentration of HNO
3
 
solution.
 
 
Table 3 shows the corresponding data of reaction number (RN) 
with concentration of inhibitor in 1N, 2N and 3N HCl solution. 
No significant temperature change were observed in lower 
conc
entration of HCl i.e. 0.5N acid. Therefore use of the 
thermometric method was restricted to 1
-
3 N acid solution. 
Research Journal of Chemical Sciences 
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ISSN 2231
-
606X
 
 
Vol. 
2
(
5
), 
51
-
56
, 
May 
(201
2
)
 
  
Res.J.Chem.Sci
 
International Science Congress Association
 
 
53
 
Table 3 indicates that reaction number increases with increasing 
strength of HCl solution as well as it decreases with increasing 
concentration
 
of inhibitor in each solution. Inhibition efficiency 
increases with increasing concentration of inhibitor in each 
solution as well as it decreases with increasing strength of HCl 
solution. Corresponding curves for the variation in reaction 
number with con
centration of inhibitor are in fig
ure 
3 for 
different concentration of HCl solution.
 
 
Results for HNO
3
 
solution of reaction number shown in 
t
able 4 
indicate that reaction number increases with increasing strength 
of acid solution as well as it decreases 
with increasing 
concentration of inhibitor of each solution. Inhibition efficiency 
increases with increasing concentration of inhibitor in each acid 
solution as well as also increases with increasing strength of 
HNO
3
 
solution. Corresponding curves for the 
variation in 
reaction number with concentration of inhibitor are shown in 
fig. 4 for different concentration of HNO
3
 
solution.
 
 
In case of HCl solution. Inhibition efficiency of inhibitor is 
maximum at lower concentration i.e. 0.5N but in HNO
3
 
solution 
inhibition efficiency of inhibitor is maximum at highest 
concentration i.e. 2.0N HNO
3
. This is because of fact that in the 
case of HNO
3
 
oxygen atom formed a protective layer on the 
metal surface, which essentially block the discharge of H
+
 
and 
di
ssolution of metal ion in acid media so they are reduce the 
corrosion rate of mild steel with inhibitor.
 
 
Conclusion
 
Both weight loss and thermometric method show that ocimum 
sanctum is a good corrosion inhibitor for mild steel in HCl 
solution. It was conc
lude that extract of stem is better corrosion 
inhibitor than that of leaves. The maximum inhibition efficiency 
shown by stem extract was 98.67% for 1.2% concentration in 
0.5N HCl. Both method show same trend for corrosion 
inhibition efficiency. Both method
s are in good agreement with 
each other.
 
 
Acknowledgement
 
One of author (Nutan Kumpawat) is greatful to R.G.N. 
fellowship from U.G.C. Govt. of India as J.R.F.
 
 
References
 
1.
 
Trabanelli G. and  Carassiti V., Achane in Corros. Sci. and 
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Nguanpuag K.Sa., Kanlayanarat S., Srilaong V., 
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Quraishi A., Singh A., Singh V.K., Yadav D.K. and Singh 
A.K., Green approach to corrosion inhibition of mild steel 
in HCl and H2SO4 solution by the extract of 
Marraya 
koenigii
 
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Chem. And Phys.,
 
(
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), 114 
(2010)
 
12.
 
Tsuyoshi Ohnishi S
.Ohnishi T. and Gabriel B., Green Tea 
extract and Aged 
Garlic extract
 
inhibit
 
anion transport ans 
sickle all dehydration in vitro, 
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Molecules and Deases
, (
27
), 148 
(2001)
 
13.
 
Ating E.I., Ymorean S.A., Udousoro I., Ebenso E.E. and 
Udoh 
A.P., Leaves extract of 
Ananas sativum
 
as green 
corrosion inhibitor for Al in HCl acid solution, 
Green 
Chem. Letters and Reviews
, 
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, 61 
(2010)
 
14.
 
Sharma P., Upadhyay R.K. and Chaturvedi A., A 
comparative study of corrosion inhibitive efficiency of 
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ly synthesize mannich bases with their parent 
amine for Al in HCl solution, 
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1(5), 
1
 
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15.
 
Kumar Mahor D., Kumar Upadhyay R., and Chaturvedi A., 
study of corrosion inibition efficiency of some sciff’s 
bases on aluminium in 
trichloroacetic acid solution, 
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Roum. Chim.
,  
55(
4),
 
227
 
(2010)
 
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Tripathi R., Chaturvedi A. and Upadhyay R.K., Corrosion 
inhibitory effects of some substituted thiourea on mild steel 
in acid media, 
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2(2),
 
18 
(2012)
 
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_
_
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_
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ISSN 2231
-
606X
 
 
Vol. 
2
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), 
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-
56
, 
May 
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2
)
 
  
Res.J.Chem.Sci
 
International Science Congress Association
 
 
54
 
17.
 
Upadhyay R.K., Anth
noy S. and  Mathur S.P.,Inhibitive 
effect of sciff’s bases as corrosion inibitor for mild steel 
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., (
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), 55 
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18.
 
Sethi T., .Chaturvedi A, Upadhyay R.K. and  Mathur S.P., 
Inhibition effect of nitrogen conteining ligands
 
on corrosion 
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., 
(
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), 591, 
(2008)
 
19.
 
Kumpawat N., Chaturvedi A. and  Upadhyay R.K.,  a 
comparative study of corrosion inhibition efficiency of stem 
and leaves extract of ocimum sanctum for mild steel i
n HCl 
solution, 
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f Metals and Phy. Chem
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,
 
(46)
 
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-
270 
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Kumpawat N., Chaturvedi A. and  Upadhyay R.K.,  
corrosion inhibitory effect of different varieties of holy 
basil on tin in acid media, 
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, 
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, 69 
(2011)
 
21.
 
Jeenga
r N., Dubey J., Chaturvedi A. and Upadhyay R.K., 
Study of corrosion inhibition efficiency of  newly 
syntesized sciff’s bases on Al in HCl solution, (
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Talati J.D. and Gandhi D.K., Derivatives to control 
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Tripathi R.,  Chaturvedi A. and Upadhyay R.K., Inhibition 
effect of substituted thioure on corrosion of Al in acid medi 
with and without NaCl
, J. Electrochem. Soc. India
, 
60(1/2),
 
73 
(2011)
 
 
Table
-
1
 
Inhibition efficiencies (

%) for mild steel in HCl solution with 
Ocimum sanctum 
extract
 
Temperature: 25 
+
 
0.1
0
C
 
 
 
 
    
 
                                 
Area of specimen: 8cm
2
 
Conc. of
 
inhibitor
 
0.5 N HCl
 
(71 hrs.)
 
1N HCl
 
(68 hrs.)
 
1.5N HCl
 
(48 
hrs.)
 
2N HCl
 
(25 hrs.)
 
(%)
 

m
 
(mg)
 

%
 
C.R.
 
(mm/yr)
 

m
 
(mg)
 

%
 
C.R.
 
(mm/yr)
 

m
 
(mg)
 

%
 
C.R.
 
(mm/yr)
 

m
 
(mg)
 

%
 
C.R.
 
(mm/yr)
 
Uninhibited
 
377.0
 
 
8.98
 
260.0
 
 
6.47
 
238.0
 
 
8.39
 
302.0
 
 
20.44
 
Stem Extract
 
 
 
 
 
 
 
 
 
 
 
 
0.3
 
19.0
 
94.96
 
0.45
 
24.0
 
90.77
 
0.59
 
22.0
 
90.75
 
0.77
 
32.0
 
89.4
 
2.16
 
0.6
 
14.0
 
96.29
 
0.33
 
19.0
 
92.69
 
0.47
 
16.0
 
93.28
 
0.56
 
23.0
 
92.38
 
1.55
 
0.9
 
10.0
 
97.35
 
0.23
 
15.0
 
94.23
 
0.37
 
15.0
 
93.7
 
0.52
 
21.0
 
93.04
 
1.42
 
1.2
 
5.0
 
98.67
 
0.11
 
10.0
 
97.35
 
0.24
 
9.0
 
96.82
 
0.31
 
13.0
 
95.00
 
0.88
 
Leaves Extract
 
 
 
 
 
 
 
 
 
 
 
 
0.3
 
25.0
 
93.36
 
0.59
 
37.0
 
86.54
 
0.92
 
41.0
 
82.77
 
1.44
 
97.0
 
67.88
 
6.56
 
0.6
 
22.0
 
94.16
 
0.52
 
25.0
 
90.38
 
0.62
 
23.0
 
90.33
 
0.81
 
94.0
 
68.87
 
6.36
 
0.9
 
20.0
 
94.69
 
0.47
 
21.0
 
91.92
 
0.52
 
21.0
 
91.17
 
0.74
 
85.0
 
71.85
 
5.75
 
1.2
 
15.0
 
96.02
 
0.35
 
15.0
 
94.23
 
0.37
 
20.0
 
91.59
 
0.70
 
61.0
 
79.80
 
4.12
 
 
Table
-
2
 
Inhibition efficiencies (

%) for mild steel in HNO
3
 
solution with 
Ocimum sanctum 
extract
 
Temperature: 25 
+
 
0.1
0
C
 
 
 
 
    
 
                                 
Area of specimen: 8cm
2
 
Conc. of
 
inhibitor
 
0.5 N HNO
3
 
(160 min.)
 
1N HNO
3
 
(45 min.)
 
1.5N HNO
3
 
(30 min.)
 
2N HNO
3
 
(20 min.)
 
(%)
 

m
 
(mg)
 

%
 
C.R.
 
(mm/yr)
 

m
 
(mg)
 

%
 
C.R.
 
(mm/yr)
 

m
 
(mg)
 

%
 
C.R.
 
(mm/yr)
 

m
 
(mg)
 

%
 
C.R.
 
(mm/yr)
 
Uninhibited
 
505.00
 
 
320.50
 
567.00
 
 
1279.47
 
663.00
 
 
2244.15
 
747.00
 
 
3792.72
 
Stem Extract 
 
 
 
 
 
 
 
 
 
 
 
 
0.3
 
282.00
 
44.16
 
178.97
 
311.00
 
45.15
 
701.79
 
328.00
 
50.53
 
1110.23
 
327.00
 
56.22
 
1660.27
 
0.6
 
280.00
 
44.55
 
177.70
 
283.00
 
50.09
 
638.60
 
255.00
 
61.54
 
863.13
 
270.00
 
63.86
 
1370.86
 
0.9
 
244.00
 
51.68
 
154.85
 
259.00
 
54.32
 
584.45
 
242.00
 
63.49
 
819.13
 
260.00
 
65.19
 
1320.09
 
1.2
 
238.00
 
52.87
 
151.04
 
241.00
 
57.50
 
543.83
 
197.00
 
70.29
 
666.81
 
212.00
 
71.62
 
1076.38
 
Leaves Extract 
 
 
 
 
 
 
 
 
 
 
 
 
0.3
 
435.00
 
13.86
 
276.07
 
406.00
 
28.39
 
916.16
 
477.00
 
28.05
 
1614.57
 
504.00
 
32.53
 
2558.94
 
0.6
 
423.00
 
16.23
 
268.46
 
396.00
 
30.15
 
893.60
 
441.00
 
33.48
 
1492.72
 
429.00
 
42.57
 
2178.15
 
0.9
 
385.00
 
23.76
 
244.34
 
377.00
 
33.51
 
850.72
 
377.00
 
43.13
 
1276.08
 
411.00
 
44.98
 
2086.76
 
1.2
 
365.00
 
27.72
 
231.65
 
316.00
 
44.26
 
713.07
 
347.00
 
47.66
 
1174.54
 
306.00
 
59.04
 
1553.64
 
 
Research Journal of Chemical Sciences 
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_
_
_______________________________
______________
_
____
 
ISSN 2231
-
606X
 
 
Vol. 
2
(
5
), 
51
-
56
, 
May 
(201
2
)
 
  
Res.J.Chem.Sci
 
International Science Congress Association
 
 
55
 
Table
-
3
 
Reaction Number and Inhibition 
efficiency (

%) for mild steel in HCl solutions with 
Ocimum sanctum 
extract
 
Temperature: 25 
+
 
0.1
0
C
 
 
 
 
 
 
 
Conc. Of 
Inhibitor
 
1N HCl
 
(240 min.)
 
2N HCl
 
(210 min.)
 
3N HCl
 
(120 min.)
 
(%)
 
RN (K Min
-
1
)
 

%
 
RN (K Min
-
1
)
 

%
 
RN (K Min
-
1
)
 

%
 
Uninhibited 
 
0.10
 
 
0.063
 
 
0.050
 
 
Stem Extract
 
 
 
 
 
 
 
0.3
 
0.034
 
66
 
0.028
 
55.55
 
0.026
 
48.0
 
0.6
 
0.028
 
72
 
0.024
 
61.90
 
0.021
 
58.0
 
0.9
 
0.021
 
75
 
0.021
 
66.66
 
0.018
 
64.0
 
1.2
 
0.018
 
81
 
0.018
 
71.42
 
0.015
 
70.0
 
Leaves Extract 
 
 
 
 
 
 
 
0.3
 
0.040
 
60
 
0.036
 
42.85
 
0.030
 
40.0
 
0.6
 
0.038
 
62
 
0.031
 
50.79
 
0.028
 
44.0
 
0.9
 
0.031
 
65
 
0.026
 
58.73
 
0.025
 
50.0
 
1.2
 
0.029
 
71
 
0.022
 
65.07
 
0.020
 
60.0
 
 
Table
-
4
 
Reaction Number and Inhibition efficiency (

%) for mild steel in HNO
3
 
solutions with 
Ocimum sanctum 
extract
 
Temperature: 25 
+
 
0.1
0
C
 
 
 
 
 
 
 
Conc. 
o
f 
Inhibitor
 
1N HNO
3
 
(240 min.)
 
2N HNO
3
 
(210 min.)
 
3N HNO
3
 
(120 min.)
 
(%)
 
RN (K Min
-
1
)
 

%
 
RN (K Min
-
1
)
 

%
 
RN (K Min
-
1
)
 

%
 
Uninhibited 
 
0.170
 
 
0.830
 
 
1.190
 
 
Stem Extract
 
 
 
 
 
 
 
0.3
 
0.100
 
41.18
 
0.390
 
53.01
 
0.430
 
63.86
 
0.6
 
0.090
 
47.05
 
0.340
 
59.03
 
0.400
 
66.38
 
0.9
 
0.080
 
52.94
 
0.300
 
63.85
 
0.370
 
68.90
 
1.2
 
0.070
 
58.82
 
0.270
 
67.46
 
0.320
 
73.10
 
Leaves Extract 
 
 
 
 
 
 
 
0.3
 
0.140
 
17.64
 
0.580
 
30.12
 
0.720
 
39.49
 
0.6
 
0.130
 
23.52
 
0.520
 
37.33
 
0.670
 
43.69
 
0.9
 
0.120
 
29.41
 
0.480
 
42.21
 
0.500
 
57.98
 
1.2
 
0.100
 
41.18
 
0.450
 
45.78
 
0.480
 
59.66
 
 
 
 
Research Journal of Chemical Sciences 
______
_
_
_______________________________
______________
_
____
 
ISSN 2231
-
606X
 
 
Vol. 
2
(
5
), 
51
-
56
, 
May 
(201
2
)
 
  
Res.J.Chem.Sci
 
International Science Congress Association
 
 
56
 
 
 
 
 
 
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