807 research outputs found
DETERMINATION OF PHENYLEPHRINE HYDROCHLORIDE IN PHARMACEUTICAL PREPARATIONS USING SPECTROPHOTOMETRIC METHOD
Objective: A simple and sensitive spectrophotometric method has been presented for the determination of phenylephrine hydrochloride by coupling reaction with diazotized sulfacetamide sodium.
Methods: The method is based on the diazotization reaction of sulfacetamide sodium with sodium nitrite in the presence of hydrochloric acid to form diazonium salt, which is coupled with the drug in alkaline medium to form azo dye, showing absorption maxima at 425 nm.
Results: Calibration plot was linear over the concentration range of 2–24 μg/mL and detection limit of 0.278 μg/mL with a correlation coefficient of 0.9929. All different chemical and physical experimental parameters affecting on the development and stability of the colored product were carefully studied.
Conclusions: The proposed method was successfully applied to the determination of phenylephrine in nasal drops with good precision and sensitivity
Generalized *⊕Z* Supplemented Modules and Generalized*⊕ Co-finitely Supplemented Modules
Let R be a commutative ring with identity, an R-module M is called G*⊕ Z* supplemented modules, if every sub module containing Z*(M) has generalized* supplement in M that is a direct summand of M . and an R-module M is called generalized*co-finitely supplemented, if every co-finite has sub module of M has a generalized* supplement in M. and M is called ⊕ co- finitely generalized* supplemented , if every co- finite sub module of M has G*S that is direct summand of M
Investigation in Optical Properties of Magnesium Doped Nanostructure Zinc Oxide Films by Pulsed-Laser Deposition Method
In the present work, films have been grown under various deposition conditions in order to understand the effect of processing on the film properties and to specify the optimum condition, namely substrate at temperatures of 400°C, oxygen pressure (2×10-1) mbar, laser fluence 0.4 J/cm2, and with different Mg contents (x=0, 0.02, 0.04, 0.06), using double frequency Q-switching Nd:YAG laser beam (wavelength 532nm), repetition rate (1-6) Hz and the pulse duration of (10 ns), to deposit MgxZn1-xO films glass substrates with thickness of about 200 nm for all MgxZn1-xO films at different deposition condition and the number of laser pulses was 100 pulses. The optical properties were characterized by the transmittance and absorption spectroscopy at room temperature, measured in the range from 300 to 900 nm. For all the films, the average transmittance in the visible wavelength region λ = (400 - 800) nm is greater than 70%. The maximum value of the transmittance (greater than 95%) was obtained for these films. Eg values of MgxZn1-xO thin films were (3.37, 3.59, 3.82, and 4.00) eV corresponding to the Mg-content (x = 0, 0.02, 0.04 and 0.06), respectively. In other word, the optical band gap of MgxZn1-xO thin films become wider as Mg-content increases and can be precisely controlled between 3.37 and 4.00 eV. The refractive index of the films ranged from 2.1-2.8 between 350nm to 900nm. The extinction coefficient and the optical conductivity of the films increases with doped. The real dielectric constant and the imaginary part increases when the doped rate increasing. Keywords: Optical properties, Pulsed-laser deposition, MgxZn1-xO Nanostructures
Observation of sub-natural linewidths for cold atoms in a magneto-optic trap
We have studied the absorption of a weak probe beam through cold rubidium
atoms in a magneto-optic trap. The absorption spectrum shows two peaks with the
smaller peak having linewidth as small as 28% of the natural linewidth. The
modification happens because the laser beams used for trapping also drive the
atoms coherently between the ground and excited states. This creates
``dressed'' states whose energies are shifted depending on the strength of the
drive. Linewidth narrowing occurs due to quantum coherence between the dressed
states. The separation of the states increases with laser intensity and
detuning, as expected from this model.Comment: 8 pages, 4 figure
The optical properties of Poly methyl methacrylate (PMMA) polymers doped by Potassium Iodide with different thickness
Films of pure Poly (methyl methacrylate) (PMMA) doped by potassium iodide (KI) salt with percentages (1%) at different thickness prepared by casting method at room temperature. In order to study the effect of increasing thickness on optical properties, transmission and absorption spectra have been record for five different thicknesses(80,140,210,250,320)µm. The study has been extended to include the changes in the band gap energies, refractive index, extinction coefficient and absorption coefficient with thickness
Evaluation of the Organic-Pollution Based on the Determination of some Polycyclic Aromatic Hydrocarbons(PAHs) in Tigris River Water in 2012 at Baghdad City , Iraq
This study aims to predict the organic pollution produced from the presence of some polycyclic aromatic hydrocarbons (PAHs) and determination it's concentrations (µg/L , ppb) in Tigris river water by a collection twenty-seven water samples from a selected three stations with nine sampling sites and three depths of water (5 cm , 2 m and 4 m) each site for 4.6 km distance of a geographic studied area which is located between the ( Al-Senak and AL-Sarrafiah bridges ) at Baghdad city – Iraq on May, 2012. The geographic location was determined with a Global Positioning System (GPS) and Geographic Information System (GIS) software program. The concentrations of fourteen components (PAHs) were performed using the reverse phase of high performance liquid chromatography (RP-HPLC) technique. Samples were chemically treated using liquid-liquid extraction method , filtered , extracted , dried , evaporated and pre-concentrated in order to be ready for analysis . The determined concentrations of (PAHs) for the studied area did exceed the criteria values proposed by the International Environmental Organizations like American Environment Protection Agency (U.S-EPA) and British Health Agency (BHA) . The results were showed that the maximum values of the total concentrations (PAHs) were found to be 228 µg/L (5 cm depth , site F, Medicine city station , Al-Resafa bank) , 192.1 µg/L (2 m depth , site D , Medicine city station , Al-Karkh bank) and 80.1 µg/L (4 m depth , site D , Medicine city station , Al-Karkh bank) , while the minimum values were found to be be 51.2 µg/L (5 cm depth , site I, Al-Sarrafia bridge station , Al-Resafa bank) , 33.4 µg/L (2 m depth , site G , Al-Sarrafia bridge station , Al-Karkh bank) and 4.8 µg/L (4 m depth , site G , Al-Sarrafia bridge station , Al-Karkh bank)
Synthesis and Characterization of New Benzothiazole-derived Schiff Bases Metal Complexes
تضمنت الدراسة تحضير معقدات جديده غير متجانسة الحلقة. تشمل هذه المركبات مشتق -2امینو 3, 1 بنزوثایازول المعوض 1 (4-كلورو-6-اوكسيد النتروز-2امینو 3, 1- بنزوثایازول (من 2-كلورو-4-اوكسيد نتروزالانیلین)) كمادة اولية ومفاعلته مع ثلاث الدیھایدات اروماتیة مختلفة بوجود الكحول المثيلي لتحضير قواعد شف ثلاثية السن 4-2. ثم مفاعلة مركبات البنزوثایازول ومشتقاته مع ايونات البوتاسيوم (I)والنيكل (II) والالمنيوم (III) لتكوين المعقدات المخلبيه7-5 (c-a). تم تشخيص تراكيب المعقدات الجديدة المحضرة بواسطة قياس درجه الانصهار، اطياف الاشعة تحت الحمراء والبعض منهم بواسطة الرنين النووي المغناطيسي البروتوني وحيود الأشعة السينية ومن نتائج الاطياف تم اقتراح شكل البنية الأساسية للمعقدات. نتوقع من هذا العمل ان يكون له اهميه في تصنيع وتطوير مواد علاجيه.Nitrogen-comprising heterocyclic compounds and their derivatives have empirically been invaluable as therapeutic agents. Fundamentally, 4-chloro-6-nitro-2-amino-1,3-benzothiazole 1 was synthesized via bromination of 2-chloro-4-nitro aniline with ammonium thiocyanate. This new heterocyclic haloorganoamino-1,3-benzothiazole derivative, was a starting material, which condensed and tethered with three different aromatic aldehyde pendant arm in presence of ethanol and glacial acetic acid isolating an interesting sequence of tridentate Schiff bases 2-4. These compounds were used for complexation reactions in 1:1 (metal: ligand) stoichiometry to obtain heteroleptic Al(III), Ni (II) and K(I) benzothiazole chelates 5-7(a-c) of the type [Al(L)Cl2, Ni(L)Cl, K(L) {L = Schiff base derivatives}]. The newly synthesized complexes were characterized by the melting points, IR and some of them by 1H-NMR spectroscopy and only one by X-ray techniques. The structures of complexes were anticipated from the spectroscopic studies
The MR affect on optical properties for poly (Vinyl alcohol) films
optical properties of pure poly(vinyl Alcohol) films and poly(vinyl Alcohol) doped with methyl red were study, different percentage prepared with constant thickness using casting technique. Absorption, Transmission spectra have been recorded in order to study the optical parameters such as absorption coefficient, energy gap, refractive index, Extinction coefficient and dispersion parameters were measured in the wavelength range (200-800)nm. This study reveals that the optical properties of PVA affect by increasing the impurity concentration
Performance analysis of image transmission with various channel conditions/modulation techniques
This paper investigates the impact of different modulation techniques for digital communication systems that employ quadrature phase shift keying (QPSK) and quadrature amplitude modulation (16-QAM and 64-QAM) to transmit images over AWGN and Rayleigh fading channels for the cellular mobile networks. In the further steps, wiener and median filters has been adopted to the simulation are used at the receiver side to remove the impulsive noise present in the received image. This work is performed to evaluate the transmission of two dimensional (2D) gray-scale and color-scale (RGB) images with different values from signal to noise ratios (SNR), such as; (5, 10 and 15) dB over different channels. The correct conclusions are made by comparing many of the observed Matlab simulation results. This was carried out through the results that measure the quality of received image, which is analyzes in terms of SNRimage peak signal to noise ratio (PSNR) and mean square error (MSE)
Performance analysis of image transmission with various channel conditions/modulation techniques
This paper investigates the impact of different modulation techniques for digital communication systems that employ quadrature phase shift keying (QPSK) and quadrature amplitude modulation (16-QAM and 64-QAM) to transmit images over AWGN and Rayleigh fading channels for the cellular mobile networks. In the further steps, wiener and median filters has been adopted to the simulation are used at the receiver side to remove the impulsive noise present in the received image. This work is performed to evaluate the transmission of two dimensional (2D) gray-scale and color-scale (RGB) images with different values from signal to noise ratios (SNR), such as; (5, 10 and 15) dB over different channels. The correct conclusions are made by comparing many of the observed Matlab simulation results. This was carried out through the results that measure the quality of received image, which is analyzes in terms of SNRimage peak signal to noise ratio (PSNR) and mean square error (MSE)
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