Simple and sensitive spectrophotometric method is described based on the coupling reaction of tetracycline hydrochloride (TC. HCl) with diazotized 4-aminopyridine in bulk and pharmaceutical forms. Colored azo dye formed during this reaction is measured at 433 nm as a function of time. Factors affecting the reaction yield were studied and the conditions were optimized. The kinetic study involves initial rate and fixed time (10 minutes) procedures for constructing the calibration graphs to determine the concentration of (TC. HCl). The graphs were linear for both methods in concentration range of 10.0 to 100.0 μg.mL-1. The recommended procedure was applied successfully in the determination of (TC. HCl) in its commercial formulations.

This paper presents a complete design and implementation of a monitoring system for the operation of the three-phase induction motors. This system is built using a personal computer and  two types of sensors (current, vibration) to detect some of the mechanical faults that may occur in the motor. The study and examination of several types of faults including (ball bearing and shaft misalignment faults) have been done through the extraction of fault data by using fast Fourier transform (FFT) technique. Results showed that the motor current signature analysis (MCSA) technique, and measurement of vibration technique have high possibility in the detection and diagnosis of most mechanical faults with high accuracy. Subsequently, diagnosi

Entropy generation was studied for new type of heat exchanger (shell and double concentric tubes heat exchanger). Parameters of hot oil flow rate, temperature of inlet hot oil and pressure drop were investigated with the concept of entropy generation. The results showed that the value of entropy generation increased with increasing the flow rate of hot oil and when cold water flow rate was doubled from 20 to 40 l/min, these values were larger. On the other hand, entropy generation increased with increasing the hot oil inlet temperature at a certain flow rate of hot oil. Furthermore, at a certain hot oil inlet temperature, the entropy generation increased with the pressure drop at different hot oil inlet flow rates. Final

The presence of alkaloids in Crassula ovata is a topic that is still unexplored, as there are no published studies on the matter. This study demonstrates the presence of an alkaloid compound (and its class) for the first time in Crassula ovata. The plant material was defatted with n-hexane, and a Soxhlet apparatus was used for the extraction process, while the acid-base method was used for the isolation of alkaloids from the chloroform fractions. The quaternary alkaloid was precipitated from the aqueous layer spontaneously, in high quantity. By using standard spectroscopic methods (including liquid chromatography - mass spectroscopy) we were able to clarify the structure of the precipi¬tated compound as a tetrahydroprotoberberine a

Nanocrystalline aluminophosphate AlPO₄-5 molecular sieves were synthesized by hydrothermal method (HTS). Synthesis parameters like time and temperature of crystallization were investigated. Type of template (R) and ratio of R/P₂O₅ were studied also. Characterization of the synthesized AlPO₄-5 were done by powder X-ray diffraction (XRD), scanning electron microscopy (SEM/EDX), Fourier transform infrared (FTIR), differential scanning calorimetry-thermogravimetry analysis (DSC-TGA), and N₂ adsorption-desorption BET analysis. XRD patterns results showed excellent crystallinity for two types of templates, di-n-propylamine (DPA) and tetrapropyl ammonium hydroxide (TPAOH) f

Oxazine and quinazoline has a very important in organic chemistry especially in hetero cyclic fields. this research consist the preparation of 4H,4'H-2,2'-bibenzo[d][1,3]oxazine-4,4'-dione compound (1) from di acid chloride with 2-aminobenzoic acid in pyridine as solvent to give compound (2) 3,3'-diamino-2,2'- biquinazoline-4,4'(3H,3'H)-dione .compound 2 include free amino group .this compound was reacted with maleic and phthalic anhydride for synthesized of cyclic imide compounds (3,4).another reaction for compound 2 with some substituted aromatic aldehyde for prepared of some novel Schiff bases (5-9) contains quinazoline ring. compound 1 was treated with sulfathiazole and sulfadiazine for synthesized of sulfa compounds contains sulf

PDBN Rashid, Multidisciplinary International Journal, 2023

Creep testing is an important part of the characterization of composite materials. It is crucial to determine long-term deflection levels and time-to-failure for these advanced materials. The work is carried out to investigate creep behavior on isotropic composite columns. Isotropy property was obtained by making a new type of composite made from a paste of particles of carbon fibers mixed with epoxy resin and E-glass particles mixed with epoxy resin. This type of manufacturing process can be called the compression mold composite or the squeeze mold composite. Experimental work was carried out with changing the fiber concentration (30, 40 and 50% mass fraction), cross section shape, and type of composite. The creep results showed that th

The aim of this research is to know danger of radioactive isotopes
that are found in samples of drugs traded in Iraqi markets. The
samples are Iraqi Amoxicillin, English Amoxicillin, UAE
Amoxicillin, Indian Amoxicillin, Iraqi Paracetamol, English
Paracetamol, UAE Paracetamol and Indian Paracetamol. By high
purity germanium the activity of the following isotopes 40K, 214Pb,
228Ac and 137Cs is measured and the specific activity was used to
calculate the annual effective dose. Then the calculated annual
effective dose values are compared with the allowable annual
effective dose values of each part of digestive channel. This research
concluded that the measured annual effective dose values are not
dangerous.<