Iraqi National Journal Of Chemistry

In this work was prepared three different types of modified screen
printed carbon electrode (SPCEs) with drops casted method, the used
carbone nanomaterials were the MWCNT, functionalized –MWCNT (f
MWCNT) and After several experiments were made to find an appropriate
ratio to make good GOT/f-MWCNT nanocomposite, and found the suspension
mixture (1:1) from GOT/f-MWCNT (f-MWCNT-GOT). The electrical and
physical properties were performed with cyclic voltammeter technique, and
studied the maximum current response, the effective surface area, effect of
the pH value and the determination of active surface area for MWCNT-SPCE ,
f-MWCNT-SPCE and f-MWCNT-GOT/SPCE as (0.04 cm2), (0.119 cm2) and
(0.115 cm2) respectively, the surface coverage concentration ( Γ) of the
material on each area was calculated and was 9.447×10-10, 9.449×10-10 and
9.3×10-10 mol cm–2 ,for MWCNT ,f-MWCNT and f-MWCNT-GOT respectively,
The values of Γ for all three types of electrodes were almost the same and no
noticeable difference. These electrodes were used to study the
electrochemical behavior of organic compound which consisting an amide
functional group, these group founded in huge spectrum of pesticide and
medicine compounds etc. the penicillin antibiotic drug family has a β-lactam
group (Azetidine-2-one) group. Therefore it was expected to show hydrolysis
with opening of the four membered ring azetidine-2-one, in a H+/1ē process.
In this work used ampicillin antibiotic AMP. The cyclic voltammetry
investigation was shown the signals of anodic peak current were higher than
the cathodic current signals Ipa/Ipc≠ 1, which indicated an irreversible electrode
reaction, with differential pulse voltammetry was studded the limit of detection
(LOD), the modification of SPCE with the f-MWCNT-GOT show the best result
than the other two carbone nanomaterial MWCNT and f-MWCNT.

The aim of this study is to fabricate and characterize ceramic composites made of
Ca10(PO4)6(OH)2 and ZrO2 using a simple powder pressing technique and to
study the effect of addition of ZrO2 on the biaxial flexural strength (BFS) of the
ceramic composites. Various compositions of hydroxyapatite (HAp)
Ca10(PO4)6(OH)2 and zirconia powder ZrO2, ranging from 10 to 90 wt% ZrO2,
were prepared using a wet mixing process. Ten compacts (13.5mm3mm) were made for each group, pressed and fired in air at sintering (firing) temperatures
from 1100 to 1450oC for up to 12 hrs. The bulk density, true porosity, linear
shrinkage and BFS were evaluated.
The true porosity reduced and linear shrinkage increased with increasing firing
temperature and amounts of zirconia, whereas the firing time had little effect. The
highest mean value achieved for the BFS was 269 MPa (20) for a composition
of 70% ZrO2 and 30% HAp fired at 1450oC for 6 hrs, however with the
hydroxyapatite (HAp) decomposed to -TCP as reported earlier [1].
We conclude that firing temperature and composition affect densification
behaviour of calcium phosphate/ZrO2 ceramic composites. The BFS increases
with a reduction of porosity and increases with both firing temperature and
additions of ZrO2. It was noted that there is considerable scope for improvement
in the BFS values by reducing the porosity of these ceramics composite. Further
work is needed to examine the crystals structure and to elucidate the
microstructural features of the composites.

Ab initio and density functional theory methods were used to study chemical
shifts and global reactivity index of 4-(4-aminophenylethynyl)picolinic acid and 4-(3
aminophenylethynyl)picolinic acid. The calculated chemical shifts for the two
molecules correlated to the experimental data. The regression factor (R2) for chemical
shifts calculated at HF/6-31G* and B3LYP/6-31G* were 0.940 and 0.964 for 4APPA
and 0.929 and 0.953 for 3APPA respectively. The absorption maxima for 4APPA
were 302.81 and 341.52 nm and 292.12 and 346.95 nm for 3APPA. Global reactivity
indexes (hardness, chemical potential and nucleophilicity) revealed that 4APPA
should be a better nucleophile than 3AAPA. The first hyperpolarizability calculated
for 4APPA and 3APPA were 8.84x10-30 and 3.41x10-30esu respectively.

The proximate composition, mineral elements contents and fatty acid
profile of Senna siamea flower were examined with a view to evaluating its
nutraceutical potentials. The proximate analysis showed that the flower contains
valuable nutrients; (g/100g) crude protein (25.49± 0.014), crude fibre (15.63±0.04),
ash (7.10±0.03), crude fat (9.68±0.04), moisture content (5.54±0.03) and
carbohydrate (36.56±0.01). The results of mineral analysis (mg/100g) indicated that
calcium, magnesium, manganese, copper, zinc, iron, cadmium and lead are 726.00,
938.00, 64.00, 30.00, 30.00, 8.00 and 16.00 respectively. The fatty acid profile of the
flower oil showed that the oil contains higher proportion of unsaturated fatty acid
(51.06 %) than saturated fatty acid (39.75 %). Among the saturated fatty acids
present, palmitic acid (31.92 %) was the most abundant while linoleic acid (20.86 %)
and linolenic acid (16.93 %) were the most abundant unsaturated fatty acids. The
results showed that the flowers of Senna siamea are good sources of essential
nutrients but the detection of cadmium and lead present calls for caution and as a
consequence, the flowers should be properly processed before consuming them.

This search include the synthesis of some new 1,3-oxazepine derivatives
have been prepared, starting from reaction of L-ascorbic acid with dry
acetone in presence of dry hydrogen chloride afforded the acetal (I).
Treatment of the latter with p-nitrobenzoyl chloride in pyridine yielded the
ester (II) which was dissolved in (65%) acetic acid in absolute ethanol yielded
the glycol (III). The reaction of the glycol (III) with sodium periodate in
distilled water at room temperature produced the aldehyde (IV).
The compound (V) [4-(1,3-dioxoisoindolin-2-yl)benzoic acid] was
synthesized by reaction
p-aminobenzoic acid and phthalic anhydride in presence of (gla. CH3COOH).
Reaction of compound (V) with thionyl chloride produced [4-(1,3
dioxoisoindolin-2-yl)benzoyl chloride]. Condensation of acid chloride with
hydrazine hydrate afforded 4-(1,3-dioxoisoindolin-2-yl)benzohydrazide (VI).
The azomethine (VII) has been synthesized from the reaction between
compounds (IV) and (VI). Moreover compounds (VIII-X) were synthesized
from the cyclic condensation of Schiff base (VII) with (maleic, phthalic and 3
nitrophthalic) anhydride, the structures of the newly synthesized compounds
have been confirmed by physical properties and spectral measurements such
as (FTIR and some of them by 1H-NMR and 13C-NMR).