The object of this work is to investigate the effect of the addition of methanol on the shelf life and color characteristics of novolak resin. Different percentages were added and two mechanisms were suggested for the addition. High ortho structure (1, 2-3) novolak resin was prepared and used in the above investigation. Experimental determination using FT-IR and UV-spectroscopy showed that on the addition of 30% of methanol and according to the second mechanism of addition novolak shelf life increased to 12 months without obvious decomposition and color change. It is suggested that methanol plays an important role in the inhabitation of the reactive sites on the resin that are responsible for the oxidation of the polymer when exposed to atmospheric or storage conditions.
There is no doubt that development is a human necessity and an urgent technical imperative that science imposes on all aspects of societal life. Especially in the field of graphic design, as logos are among the most prominent graphic achievements of an interactive nature with the requirements of the technical and functional era to serve the recipient and the continuity of interaction with him through a visual message sent to him constantly to remind him of what he interacted with in advance, which is known as visual identity, and during the process of developing logos especially And by providing designs that suit the contemporary technical and functional development, we often see the logo lose its visual identity. Therefore, the research
... Show MoreThis research is concerned with the study of (the dialectic of the familiar and the unfamiliar in Islamic photography), and it consists of four chapters.
If you dealt with the problem of the research subject (the dialectic of the familiar and the unfamiliar in Islamic photography, as it appeared realistic, familiar forms and strange and strange unfamiliar forms represented in many of the main schools of Islamic photography that emerged in Iraq and Persia and then the Ottomans and the However, Islamic painting still retains those previously witnessed and unseen images, which pose themselves forcibly in the form of many questions that must be faced and studied by investigation, observation, extrapolation and conclusion through scientifi
Orthogonal Frequency Division Multiplexing (OFDM) is an efficient multi-carrier technique.The core operation in the OFDM systems is the FFT/IFFT unit that requires a large amount of hardware resources and processing delay. The developments in implementation techniques likes Field Programmable Gate Array (FPGA) technologies have made OFDM a feasible option. The goal of this paper is to design and implement an OFDM transmitter based on Altera FPGA using Quartus software. The proposed transmitter is carried out to simplify the Fourier transform calculation by using decoder instead of multipliers. After programming ALTERA DE2 FPGA kit with implemented project, several practical tests have been done starting from monitoring all the results of
... Show MoreBackground: Excessive crying in early
infancy is a common condition that causes a
great deal of concern to the parents and
physician.
Objective: The aim of this study is to find
the underlying etiology of excessive crying in
infancy and to determine how the history,
physical examination, and laboratory
investigations contribute to the final diagnosis.
Method: A prospective study done on 150
afebrile infants less than 4 months of age
visited Al-Elwia hospital for children
complaining of excessive crying of more than
two hours.
The study done over a one year period from
the first of January 2009 to the end of
December 2009.
All febrile infants and those with acute illness
preceding the
China and India are considered both rising countries, and both are among the world's most populous and fastest growing economies. The long-term growth of both China and India has reinforced the importance of their bilateral relationship. The relations between China and India are complex, as relations between them have undergone great changes during the past seven decades, ranging from friendship to hostility. This study proceeds from the hypothesis that the nature and path of Sino-Indian relations after 2013 are affected by several factors and variables, some of which represent opportunities, others represent challenges and obstacles. Several opportunities have contributed to the reformulation of bilateral relations in terms of mutual ga
... Show MoreThree of imide intermediate products were synthesized by reacting of phthalic anhydride with glycine (2a), and tetrachloro phthalic anhydride with glycine , (S)-2-[(tert-Butoxycarbonyl)amino]-3-aminopropionic acid ( 2b,c) respectively in dry toluene with azeotropic removal of water using Dean- stark apparatus then carboxyl functional group activated by refluxing with thionyl chloride, the resulted acid chloride (3a-c) were reacted with different amine (5-flourouracil, 4-chloroaniline, 4-bromoaniline, 2-amino thiazole, and pyrrolidine) (4a-e) , the resulted products consider as
... Show MoreMeloxicam is a non-steroidal anti-inflammatory drug. It is practically insoluble in water. It is associated with gastrointestinal side effects at high doses on long term treatment. The aim of this investigation to formulate and evaluate gellified nanoemulsion of meloxicam as a topical dosage form to enhance meloxicam therapeutic activity and reduce systemic side effect.
The pseudo ternary phase diagrams were made, including the oil mixture which is composed of almond oil and peppermint oil at a ratio (1:2), variable surfactant mixture (S mix) which are tween 80 and ethanol at ratios of (1:1, 2:1, 3:1, and 4:1) and double distilled water. Slow dripping of double distilled water to the combination of the oil mixtu
... Show MoreIn this review, previous studies on the synthesis and characterization of the metal Complexes with paracetamol by elemental analysis, thermal analysis, (IR, NMR and UV-Vis (spectroscopy and conductivity. In reviewing these studies, the authors found that paracetamol can be coordinated through the pair of electrons on the hydroxyl O-atom, carbonyl O-atom, and N-atom of the amide group. If the paracetamol was a monodentate ligand, it will be coordinated by one of the following atoms O-hydroxyl, O-carbonyl or N-amide. But if the paracetamol was bidentate, it is coordinated by atoms (O-carbonyl and N-amide), (O-hydroxyl and N-amide) or (O-carbonyl and O-hydroxyl). The authors also found that free paracetamol and its complexes have antimicrobial
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