Iraqi National Journal Of Chemistry

The study is concerned with the influence of non polar solvents as DCE and DCM
and polar solvents as ethanol and acetone on tautomerism reaction process of type
enol keto in eight different imines structures prepared by the reactions of 2-
hydroxy-1-napthyl aldehyde with an appropriate primary amines. Three different
empirical parameters for solvent polarity are used as ET
N , μ10
-30
cm and ET(30)
Kcal/mole -1 , beside their influence on tautomerism process in imines under study.
Finally , the study comes to a conclusion that the equilibrium constant value of
tautomerism reaction is largely depend on the structure or type of substituent of
imines and the type pf solvent used through out the study. The last is supported by
the appearance of a very good linear plot from Hammett equation when applied to
imines and discussed.

The work reports an investigation of the interaction of Cu2+ ion with the ligand
o-Phenylenediamine (1,2-diaminobenzene). Two spectrophotometric methods namely
the continuous variations and the molar ratio were used. The continuous variations
was applied to determine whether, one complex or more is formed from the reaction
of the metal ion Cu2+ with the ligand in a given pH value.
The results which are obtained from the pervious method was affirmed by the
molar ratio method. Moreover, the effect of the experimental variables such as pH,
concentration, time and temperature upon the extent of complex formation were
studied. Also the stability constant (K) for Cu2+ complexes was calculated.

The new thermometric sensor developed by the present authors and appeared in (Talanta,
2007, 71(1),141-148) has been subjected to further applications. In this work Ce(IV) has
been determined using Reverse Injection Enthalpimetry (RIE) , in which the analyte Ce(IV)
was added to excess reagent (sulphanilic acid). For the determination of (4 - 35 μg.mL-1)
Ce(IV) in the final solution, a fixed volume between (0.1 – 0.8)mL. analyte present in .
(0.5 M H2SO4), was injected into an excess of sulphanilic acid (20 ml. 1.25x10-2M) in the
thermometric cell. Only one blank of 0.5 ml.(0.5 M H2SO4) was performed and its value
was subtracted from all the results. The calibration curve was linear with R2 = 0.999 with a
recovery between 96 – 101% with precision of about 2%, and t-test showed no significant
difference between the true value and the mean at 95% confidence limit, indicating good
validity of the method. The above procedure was reversed for the determination of
sulphanilic acid and some sulpha drugs. In this case a portion of 0.5 mL. of the analyte or the
standard containing not less than 10mg of sulphanilic acid or the sulpha–drug is injected into
an excess of Ce(IV) as a reagent in the thermometric cell and the procedure will be
continued.

A sensitive and selective spectrophotometric method is proposed for the rapid
determination of cobalt (II) using 4- (6- nitro-2- benzothiazolylazo) resorcinol (6-
NO2BTAR).The reaction between 6-NO2BTAR and Cobalt (II) is instantaneous at pH
6.0 and the absorbance remains stable for over 24h. The method allows the
determination of cobalt over the range (1-8) μg/ml with molar absorptivity of (4857.1)
L.mol-1.cm-1 and features a detection limit of (0.2) μg/ml at 458 nm. The precision
(R.S.D%<1%) and the accuracy obtained were satisfactory. The proposed method has
been successfully applied to the determination of cobalt in filling.

The degree of cross linking condensation polymerization of rayon molecule
under argon atmosphere is a function of temperature in the
range (200 – 230)°C with liberation of 10%, 10.5%, and 10.9% water respectively from
the fiber weight. Elemental analyses show increasing of carbon % on the expense of
hydrogen and oxygen percents in the same order. Above 230°C self-carbon dioxide is
generated. The fiber resulted from the polymerization shows fire resistance and
insoluble in sulfuric acid which is in opposite behavior to the untreated fiber. Also
treated fiber shows color change from white → yellow→ brown→ black depending on
temperature degree and duration of heating with smooth and oily surface appearance
due to the new bonding system and more close rayon molecules upon polymerization,
accompanied with what is called chemiluminescence phenomenon.
Polymerization under nitrogen atmosphere shows early liberation of carbon
dioxide gas beside water due to the presence of oxygen even in trace amount in the
nitrogen gas which attacks the rayon molecules at the above temperature.

The effect of polyacryclic acid (PAA) on rheological properties of maleated
low density polyethylene (MALDPE) was studied. The presence of maleic
anhydride (MAH) on the LDPE backbone increase the interface interaction via
chemical or physical interactions between the polymers in the blend.FTIR
spectroscopy of the MALDPE, PAA and MALDPE/PAA shows new peak shifted
to lower frequency. The shear stress, shear rate, apparent viscosity and swelling
ratio were evaluated using Instron capillary Rheometer. For all samples the
rhological properties measured at 170oC and various cross head speed. The results
showed increasing shear stress and decreasing apparent viscosity when shear rate
increase. At higher PAA weight content the die swell for all blends reduced.

The aims at investigation the tautomerism reaction of mono and bi aromatic
Schiff bases by actions of different values of pH,s and temperatures. The pH under
study was chosen in a range between 4-10.
Experiments prove the existence of Schiff bases under study, as tautomeric
equilibrium mixture of different ratios of keto and enol forms , as well as , the
formations of nitrilium and phenoxonium ions in acidic and basic media respectively.
Equilibrium constants K for the tautomerism reaction are evaluated at a temperature
range between 298-338k. the last shows an inverse relationship between K and T
which facilitates the evaluation of thermodynamic parameters. Finally evidence for
supporting the tautomerism reaction is mentioned and disussed.

This work deals with the preparation and thermal investigation of eleven
Epoxy-amic acid or Imide networks. The following monobasic amic acids were used:
PMA, 2CMA, 3CMA, 2,6DCMA, 2BMA, 4NMA, 2HMA and 2MMA. Also the
following dibasic amic acids were prepared: 1,2PBMA, 1,4PBMA and 2,5TBMA.
After characterization with IR spectroscopy, thermal behaviour of the networks were
investigated by using differential thermal analysis (DTA). The comparison of T1 and
T4 values of amic acids alone with those in the networks shows that T1 values are
lower and T4 values are higher in networks. As well as, the similarity of T1 and T4
values of amic acid networks with those of imide networks. The derivation of T2 and
T3 values reveals that cyclo-dehydration process affects T2 and T3 positions but not the
initial or final positions.

X-ray powder diffraction, x-ray fluorescence, infrared spectroscopy,
thermogravimetric, differential thermal analysis, and chemical analysis were performed
to study the physical properties, crystal structure and chemical composition of silica rich
Ninivite silica rocks and Iraqi natural Fuller’s earth.
The results were compared with that obtained from mixing the two samples in a
ratio 1:1. These samples have been used as adsorbents in fractionating columns to
fractionate Qaiyarah Heavy Crude (QHC) Oils into their simple components.

The ligand [1,2-diaminoethane –N,Ń-bis (2-butylidine -3-onedioxime)][H2L]. was reacted
with Co(NO3)2.6H2O and KBr in ethanol with reflux in (1:1) metal : ligand ratio to give a
new complex of the general formula [CoIII(HL)Br2]. A series of new complexes with some
heterocyclic nitrogen and aliphatic amine ligands of the general formula [CoIII(HL)(X)Br]Br
(where: X=pyridine, 4-picoline, and 3-picoline, piperidine, octylamine, n-propylamine and
Br) were prepared. All compounds have been characterised by spectroscopic methods [IR,
U.V-Vis, atomic absorption, (1H NMR, and EI-mass spectroscopy for the ligand)],
microanalysis andwith conductivity measurements. From the obtained data, a distorted
octahedral molecular structure about Co(III) ion has been proposed.

A series of heterocyclic compounds 1,2,4-5H oxadiazol [4a-e,5a-c] derivatives were
prepared by the reaction of aldehyde and ketone with amidoxime in which the latter was
obtained from the reaction of corresponding nitrile with hydroxyl amine hydrochloride. The
prepared compounds were characterized by IR spectra.

Some dipeptide amide and amino derivatives of 7-chloro-4,5-dioxopyrano
[3,4-e]-l,3-oxazine, compounds (2a-d) and (3a-e) respectively have been synthesized
and studied against five species of bacteria in vitro. A significant activity against
staph. Aureus and Bacelus Subtilis were observed by the above derivatives at
concentration ranging from (0.1-10 mg./ml.) and remarkable activity was exhibited by
2-(N-glycyl glycine amido)-7-chloro-4,5-dioxopyrano [3,4-e]-l,3-oxazine (2a). Other
compounds showed no significant activities. The I.R. and NMR spectral data of the
synthesized compounds were also discussed and are included.

Chemical analysis of different diet commonly used by population in Iraq to
determine the concentration of phosphorus in some vegetable, fruits, dairy products,
meat, eggs, and different foods and compared with the international value of the
same food.
The differences in concentration of phosphorus in foods could be due to the
geographical situation, environment and genetic variation, in addition other factors
in soil and nutrition which may influence it. The list of good sources was derived
from the same nutritive value of foods tables used to analyze information for recent
food consumption surveys.
Finally this study will help the people to select the diet of good sources of
phosphorus according to the chemical analysis.

The present study on β–Thalassemia major patients as regard to oxidative
hypothesis to explain the influence of the free radicals and other reactive
oxygen species (ROS) that accelerate the damage of cells and cause to
complication of these patients. The measurement of antioxidant enzymes,
Superoxide dismutase (SOD), Catalase (Cat) and glutathione reductase (GR)
explanted a significantly increased for all age groups of patients compared
with healthy controls. A significantly decrease of Vitamins E and A, which
determined for the first time for thalassemia patients by using a Gas
chromatography technique, our results proved that the patients suffer from
deficiency on the levels of vitamins E and A as well as vitamin C, our
study detect a significant decrease in Vitamin C (ascorbic acid) concentration
at all age groups of patients as compared to healthy controls of similar age
group.
Study of vitamin E / vitamin C ratio ( the means ± SD are 0.7 ± 0.3, 0.84
± 0.21, 0.88 ± 0.23, 0.85 ± 0.46 ) for age groups of patients compared with
healthy controls ( 1.5 ± 0.3 and 0.99 ± 0.4). Also the correlation between
SOD and Cat activity were study which can use as an index for the iron
overload and oxidative stress in patients with β– Thalassemia major.