This work represents implementation and investigation of optical coherent communication system between two computers. A single mode optical fiber is selected as transmission medium. The data are sent via the RS-232 standard interface with a bit rate of 9.6 kbps from personal computer (PC1) by line receive to convert the data from electrical levels (-12/+12 V) into TTL level (0/5 V). The modulation of this data was accomplished by internal modulation using laser diode type (HFCT-5208M) 1310 nm wavelength. The optical D-coupler was used to combine the optical signal that come from laser source with optical signal of laser local oscillator (OTS-304XI) at 1310/1550 nm wavelength to obtain coherent (homodyne and heterodyne) detection respectively. A PIN photodetector (HFCT-5208M) is used. Calculations of Signal to Noise Ratio (SNR) and Bit Error Rate (BER) for coherent detection were measured at different length of the optical fiber. Result show that high SNR and low BER for heterodyne detection than for homodyne detection.
This study detects the presence of cholesterol in an Iraqi plant named Suaeda baccata Forsk of the family Chenopodiacae, wildly and widely grown in Iraq. The absence of any publication concerning the sterol content of this Suaeda specie, and the industrial importance of cholesterol depending on its role as a precursor in the synthesis of some hormones, like progesterone, acquired this study its value. The investigations revealed the presence of cholesterol that was proved by TLC together with the standard compound cholesterol, and anisaldehyde spray reagent using three different solvent systems, then authenticated by HPLC, in which the reten
... Show MoreBackground: Since its introduction to musculoskeletal imaging in the early 1980, magnetic resonance imaging (MRI) has revolutionized diagnostic imaging of the knee. It is therefore become the examination of choice in the evaluation of internal joint structures of the knee like menisci, cruciate ligaments, and articular cartilage.Objectives: to describe the MRI finding in various knee injuries.Patients and methods: A cross sectional study was done on 130 patients with history of knee injury in MRI unit at institute of radiology and al-Shaheed Ghazi Al-Hariri Hospital in medical city complex - Baghdad, from October 2011 to February 2013 includes 103 men, 27 women; the mean age was 33.86 years. MR imaging studies of the knee performed using
... Show MoreThis research is based on the study of a group of Quranic verses that share a certain part, and these verses are verses of righteousness, and the word righteousness has been mentioned in the Holy Qur’an eight times, and the number of verses in this word was six verses, in four walls, all of which are from the civil fence which is the cow and was There are five words of righteousness contained in them, and the family of Imran is one word, and the table is one word, and the argument is one word. This study adopts the method of analytical interpretation of the Quranic text is a term that means statement and clarification in a way that the researcher produces to divide a Quranic text into its elements that are involved in its formation and
... Show MoreSamples of twelve species belong to mimosoideae were collected from baghdad. The current study aimed to screen the bioactive compounds from leaves methanol extracts of twelve species from Mimosoideae to assess the phytochemical compounds properties. The twelve species of Mimosoideae
Review Article Immunomodulatory Role of Cytokines in Periodontal Disease Batool Hassan Al-Ghurabi*, Maha Adel Mahmood, Zainab A. Aldhaher, Sahar Hashim Al-Hindawi Adv. life sci., vol. 11,...
The bandwidth requirements of the telecommunication network users increased rapidly during the last decades. Optical access technologies must provide the bandwidth demand for each user.The passive optical