The Atmospheric Infrared Sounder (AIRS) on EOS/Aqua satellite provides diverse measurements of Methane (CH4) distribution at different pressure levels in the Earth's atmosphere. The focus of this research is to analyze the vertical variations of (CH4) volume mixing ratio (VMR) time-series data at four Standard pressure levels SPL (925, 850, 600, and 300 hPa) in the troposphere above six cities in Iraq from January 2003 to September 2016. The analysis results of monthly average CH4VMR time-series data show a significant increase between 2003 and 2016, especially from 2009 to 2016; the minimum values of CH4 were in 2003 while the maximum values were in 2016. The vertical distribution of CH4 was relatively high in the cities located in the north of Iraq (Sulaymaniyah and Mosul) more than other cities, especially these in western Iraq (Rutba and Najaf). The highest monthly mean of CH4VMR and standard deviation (SD) was in Sulaymaniyah (1871.11±21.92) ppbv at 925 hPa, while the lowest was in Rutba (1812.81±37.3) ppbv at 300 hPa. Mosul has the second-highest mean and SD next to Sulaymaniyah, especially at the lower levels SPL (925 and 850 hPa) of troposphere more than the rest of selected cities. The seasonal variation of monthly CH4VMR, averaged from 2003 to 2016, shows high values between January and August with a peak between August and September and it declines significantly between October and December with a slight increase in November. Long term trend analysis of monthly CH4VMR at each SPL (925, 850, 600, and 300) hPa above the six cities shows positive values with average growth rates for each SPL equal to (2.9 %, 3.1%, 3.6 %, and 3.9%), respectively. These results indicate that satellite measurements were effective in determining the magnitude of increased CH4 over Iraq that may contribute to the global increase of CH4 in the earth’s Atmosphere.
Background: The displacement of artificial teeth during complete denture construction presents major processing errors in the occlusal vertical dimension which were verified at the previous trial denture stage. The aim of this study was to assess the effect of delay in processing after final flask closure and tension application on the vertical acrylic and porcelain teeth displacement of complete dentures constructed from heat cured acrylic and the results were compared with the conventional processing method. Materials and methods: forty samples of identical maxillary complete dentures were constructed from heat polymerized acrylic resin. These samples were subdivided into the following experimental subgroups in which each subgroup contai
... Show MoreThe current study sheds light on the measurement and estimation of the radioactivity of radionuclides (238U, 226Ra, 232Th, and 40k) in natural waters of different regions of Nineveh Governorate in Iraq.15 samples were collected from different sources of natural waters, where gamma-ray spectroscopy was used using NaI)TI) sodium iodide detector to determine the concentration of radioactivity in the samples. According to the results, the radioactivity concentration in the tested water sample were ranged from 0.36 ± 0.04-1.57 ± 0.09with an average value of 0.69 ± 0.06 Bq/l for 238U, and 2.9 ± 0.02-0.88 ± 0.03 with an average value of 0.65 ± 0.03 Bq/l for 226Ra Bq/l
... Show MoreThe present study was performed to spotlight the potential role of soil bacteria in the Al-Rumaila oil field as a bioindicator of heavy metals pollution. For this purpose, nine soil samples were collected from different sites, with 20cm depth, to assess the pollution status depending on the total and available concentrations of heavy metals. The result indicates pollution of the studied soils with the following metals: Cd, Cu, Fe, Zn, and Pb. The mean of total concentration for all studied metals was higher than the allowed maximum limit based on the international limit:(3.394, 3.994, 39.993, 8844.979,150.372, and 103.347 µg/g), respectively. While measuring the total Metal concentration is important in determining the de
... Show MoreThe aim of this research is to determine the uranium concentration and its distribution in many sheep organs that live in different region of Iraq. The uranium concentration in tissue samples is measured by using fission tracks registration in CR-39 detector that caused by the bombardment of U235 with thermal neutrons from (241Am-Be) neutron source of thermal flux (5x 103 n.cm-2. s-1). The results show that the maximum uranium concentration in bronchiole tissues of the animals was found in Karbala city (3.706ppm) while the minimum concentration (0.127 ppm) was found in Al-Faluja city, also the same result in lung tissue the maximum value was found in Karbala city (2.313ppm) and the minimum concentration in Al Fluja (0.082). Otherwise,
... Show MoreCipher security is becoming an important step when transmitting important information through networks. The algorithms of cryptography play major roles in providing security and avoiding hacker attacks. In this work two hybrid cryptosystems have been proposed, that combine a modification of the symmetric cryptosystem Playfair cipher called the modified Playfair cipher and two modifications of the asymmetric cryptosystem RSA called the square of RSA technique and the square RSA with Chinese remainder theorem technique. The proposed hybrid cryptosystems have two layers of encryption and decryption. In the first layer the plaintext is encrypted using modified Playfair to get the cipher text, this cipher text will be encrypted using squared
... Show MoreStenography is the art of hiding the very presence of communication by embedding secret message into innocuous looking cover document, such as digital image, videos, sound files, and other computer files that contain perceptually irrelevant or redundant information as covers or carriers to hide secret messages.
In this paper, a new Least Significant Bit (LSB) nonsequential embedding technique in wave audio files is introduced. To support the immunity of proposed hiding system, and in order to recover some weak aspect inherent with the pure implementation of stego-systems, some auxiliary processes were suggested and investigated including the use of hidden text jumping process and stream ciphering algorithm. Besides, the suggested
... Show MoreChaotic systems have been proved to be useful and effective for cryptography. Through this work, a new Feistel cipher depend upon chaos systems and Feistel network structure with dynamic secret key size according to the message size have been proposed. Compared with the classical traditional ciphers like Feistel-based structure ciphers, Data Encryption Standards (DES), is the common example of Feistel-based ciphers, the process of confusion and diffusion, will contains the dynamical permutation choice boxes, dynamical substitution choice boxes, which will be generated once and hence, considered static,
While using chaotic maps, in the suggested system, called