New thermally stable aromatic poly(amide-imide)s ( PAI1- PAI4 ) were synthesized from direct polycondensation reaction of Terephthalic acid and Phthalic acid with two new different diamine monomers derivatives of 1,2,4,5-tetracarboxilic benzene dianhydride as a second diacides in a medium consisting of triphenyl phosphite (TPP) in N-methyl-2pyrrolidone (NMP) / pyridine solution containing dissolved calcium chloride CaCl2. The polymerization reaction produced a series of novel poly(amide-imide) in high yield. The new monomers were characterized by FTIR, 1H-NMR spectroscopy. The resulting polymers were typically characterized by means of FT-IR, 1H-NMR spectroscopy, and solubility tests. Thermal properties of the poly(amide-imide)s were also investigated using differential scanning calorimetry (DSC). Data obtained by thermal analysis revealed that these polymers showed very good thermal stability. These polymers were readily soluble in various organic solvents.
The laboratory experment was conducted to study the effect of H2O2 with 5ppm,10 ppm and Uric Acid with 5ppm,10 ppm concentration on seed germination and seedling growth of Zea Mays L.
The result showed that the H2O2 and Uric Acid effect significantly to increase percentage of seed germination , seedling vigor index,dry weight and proline concentration compared with control treatment ,given the concentration of each H2O2 and Uric Acid of the best result of seed germination 70.00%,76.00% and seedling vigor index 21.00%,26.00% and dry weight give in 5ppm to Uric Acid significantly increased 0.34%,the 10 ppm to H2O2 increased proline concentration in plant compared with control treatment
This contribution reports a comprehensive investigation into the structural, electronic and thermal properties of bulk and surface terbium dioxide (TbO2); a material that enjoys wide spectra of catalytic and optical applications. Our calculated lattice dimension of 5.36 Å agrees well with the corresponding experimental value at 5.22 Å. Density of states configuration of the bulk structure exhibits a semiconducting nature. Thermo-mechanical properties of bulk TbO2 were obtained based on the quasi-harmonic approximation formalism. Heat capacities, thermal expansions and bulk modulus of the bulk TbO2 were obtained under a wide range of temperatures and pressures. The dependency of these properties on operational pressure is very evident. Cle
... Show MoreSediments samples from ten stations along the Euphrates River and seven
samples from selected springs within Al –Anbar governorate, (western part of Iraq),
were collected and analyzed for radioactivity. Sediments samples were dried at 100
ºC for 24 hours. Radioactivity in 1 kg of each sample was measured using gamma
spectrometer system based on a pure germanium detector with efficiency 30%. The
activity of Ra-226, Th-232, K-40 were measured to be within the typical average of
the radioactivity in sediment in world rivers, while relatively elevated concentration
were found in the sediment of some of the studied spring. In current study activity
concentrations of Cs-137 in the sediments were detected which may be
Celery and coriander are vastly applied in modern medicine and traditionally because various medicinal and nutritional benefits depend on their medicinal characteristics. The study aimed to detect, isolate and compare extracts contents of phenolic acids (caffeic and p-coumaric acids) in ethyl acetate fraction of fresh and dry aerial parts of coriander (Coriandrum sativum L.) and celery (Apium graveolens L.) of the Apiaceae family. The extraction of these constituents was carried out by maceration method using 70% ethanol and fractionation was done by using petroleum ether, and ethyl acetate. The existence of caffeic and p-coumaric acids in aerial part extracts of two plants was identified by thin-layer chromatography (TLC) and high-
... Show MoreIn oil and gas well cementing, a strong cement sheath is wanted to insure long-term safety of the wells. Successful completion of cementing job has become more complex, as drilling is being done in highly deviated and high pressure-high temperature wells. Use of nano materials in enhanced oil recovery, drilling fluid, oil well cementing and other applications is being investigated. This study is an attempt to investigate the effect of nano materials on oil well cement properties. Two types of nano materials were investigated, which are Nano silica (>40 nm) and Nano Alumina (80 nm) and high sulfate-resistant glass G cement is used. The investigated properties of oil well cement included compressive strength, thickening
... Show MoreCadmium sulfide (CdS) thin films with n-type semiconductor characteristics were prepared by flash evaporating method on glass substrates. Some films were annealed at 250 oC for 1hr in air. The thicknesses of the films was estimated to be 0.5µ by the spectrometer measurement. Structural, morphological, electrical, optical and photoconductivity properties of CdS films have been investigated by X-ray diffraction, AFM, the Hall effect, optical transmittance spectra and photoconductivity analysis, respectively. X-ray diffraction (XRD) pattern shows that CdS films are in the stable hexagonal crystalline structure. Using Debye Scherrerś formula, the average grain size for the samples was found to be 26 nm. The transmittance of the
... Show MoreBackground:
Inflammatory bowel disease (IBD) is a chronic inflammatory disorder, the etiology and pathogenesis of which have been suggested to be influenced by cytokines. Two main clinical types of IBD are recognized, namely ulcerative colitis (UC) and Crohn's disease (CD). The present study examined serum levels of two cytokines (IL-17A and IL-23) in 60 IBD patients (30 UC and 30 CD) and 30 healthy controls. The levels were correlated with age, gender, cigarette-smoking status, disease duration, family history, disease extension, symptoms, extra-intestinal manifestations, and medication. The results depicted that IL-17A level was significantly higher in UC and CD patients compared to control (45.2 ± 23.3 and 47.5 ±
... Show MoreTetragonal compound CuAl0.4Ti0.6Se2 semiconductor has been prepared by
melting the elementary elements of high purity in evacuated quartz tube under low
pressure 10-2 mbar and temperature 1100 oC about 24 hr. Single crystal has been
growth from this compound using slowly cooled average between (1-2) C/hr , also
thin films have been prepared using thermal evaporation technique and vacuum 10-6
mbar at room temperature .The structural properties have been studied for the powder
of compound of CuAl0.4Ti0.6Se2u using X-ray diffraction (XRD) . The structure of the
compound showed chalcopyrite structure with unite cell of right tetragonal and
dimensions of a=11.1776 Ao ,c=5.5888 Ao .The structure of thin films showed