Nowadays, energy demand continuously rises while energy stocks are dwindling. Using current resources more effectively is crucial for the world. A wide method to effectively utilize energy is to generate electricity using thermal gas turbines (GT). One of the most important problems that gas turbines suffer from is high ambient air temperature especially in summer. The current paper details the effects of ambient conditions on the performance of a gas turbine through energy audits taking into account the influence of ambient conditions on the specific heat capacity ( , isentropic exponent ( ) as well as the gas constant of air . A computer program was developed to examine the operation of a power plant at various ambient temperatures and relative humidities. The ambient temperatures ranged from 0 to 45 ºC, with relative humidities from 10 to 90%. The obtained results show that a GT operated at increased inlet air temperatures is characterized by lower net power and thermal efficiency. At higher inlet air temperatures, increased relative humidity has a slight positive impact on the GT cycle net power and its thermal efficiency. Net output power of the GT decreased from 93.3 MW at 15 °C to 70 MW at 45 °C. Its efficiency decreased from 32.32% at 5 °C to 28.3% at 30 °C. Although fuel consumption is reduced, the heat rate as well and the specific fuel consumption (SFC) are enhanced. SFC increased by 5.36% with a 10 °C temperature rise in temperature at a constant relative humidity. Therefore, use of a gas turbine with inlet air cooling and humidification is appropriate for improved GT efficiency.
Objective: The study aim to evaluate secondary schools students' exposure to risk factors in Al-Najaf City. Methodology: Descriptive study conducted in Al- Najaf City/Iraq on students at secondary schools, those aged (12-24) years old, for the period from the 13ed of November 2015 and up to 4ed of August 2015. The sample included secondary school from those schools . Data is collected through a constructed questionnaire, reliability and students (intermediate and secondary) (540) student; (270) male and (270) females who are selected randomly content validity process has been determined for the instrument. Dat
Bacterial water pollution is a genuine general wellbeing concern since it causes various maladies. Antimicrobial nanofibers can be integrated by incorporating nanobiocides, for example, silver nanoparticles into nanofibers. Nylon 6 was dissolved in formic acid at a concentration of (25 wt. %) and tough antibacterial (AgNO3/Nylon) nanofibers were produced utilizing electrospinning system. Polymer solution was tested before accomplishing electrospinning process to acquire its surface tension, electric conductivity and viscosity, where every one of those parameters increased relatively with increasing concentration of (AgNO3) additions. SEM and EDX spectra were utilized to focus on the morphology, surface elemental mem
... Show MoreBackground: The normal decline in systolic blood pressure during recovery phase of treadmill exercise dose not occur in most patients with coronary artery disease, in others recovery values systolic blood pressure may even exceed the peak exercise value. Objectives: Treadmill exercise test parameters indicating the presence and extent of coronary artery disease have traditionally included such as exercise duration, blood pressure and ST-segment response to exercise. The three –minute systolic blood pressure ratio is another important indicator of presence and significance of coronary artery disease is useful and obtainable measure that can be applied in all patients who are undergoing stress testing for evaluation of suspected is
... Show MoreBackground: psychiatric and behavioral side effects are
common in patients with epilepsy and it may represent an
intrinsic feature of the disease itself or a side effect of the
antiepileptic use. Our aim in the present study is to assess
the psychiatric side effects of Sodium Valproate and
Carbamazipine .as these drugs are the most commonly
used antiepileptic drugs in Iraq.
Methods: 80 patients with primary generalized epilepsy
on Carbamazipine and 50 patients on Sodium Valproate
were enrolled in the present study; all the patients were
assessed for any psychological disturbances using semistructural interview based on the tenth edition of the
international classification of the diseases(ICD 10)
adopte
Objective: Assessment of primary schools science teachers' knowledge towards health promotion in Baghdad City.
Methodology: A descriptive study was conducted at (100) primary school at Al-Rasafa, and Al-Karkh sectors in
Baghdad City, from November 29th 2007 to January 20th 2009. A probability stratified random sample of (100)
teachers who teach science subject was selected, and had at least one year of employment in the teaching field. A
questionnaire format was used which was consisted of (2) parts. The overall number of the items included in the
questionnaire were (205) items. The first part was related to the demographic data of the teachers, the second part
(six sections) was concerned with teachers' knowledge about
One of the most important problems confronts hospitals is the strains emergence of Enterococcus spp. with multiple resistance to antibiotics, which propel researchers to modify or produce new antibiotics or combination between two antibiotics so that to be more effective against Enterococcus . This study was aimed to susceptibility some of local Enterococcus spp. Isolates with of 21 antibiotic using disc diffusion method. The results showed absolute resistant 100% toward (Cephalexin , Gentamycin , Amikacin ,Erythromycin and Nalidixic acid), while showed a high sensitivity toward (Vancomycin and Impenem ) at percentage of 92.3% for each . Also highl
... Show MoreThis paper presents a study to investigate the behavior of post-tensioned segmental concrete beams that exposed to high-temperature. The experimental program included fabricating and testing twelve simply supported beams that divided into three groups depending on the number of precasting concrete segments. All specimens were prepared with an identical length of 3150 mm and differed in the number of the incorporated segments of the beam (9, 7, or 5 segments). To simulate the genuine fire disasters, nine out of twelve beams were exposed to a high-temperature flame for one hour. Based on the standard fire curve (ASTM – E119), the temperatures of 300◦C (572◦F), 500◦C (932◦F), and 700◦C (1292◦F) were adopted. Consequently,
... Show MoreIn this paper, the Decomposition method was used to find approximation solutions for a system of linear Fredholm integral equations of the second kind. In this method the solution of a functional equations is considered as the sum of an infinite series usually converging to the solution, and Adomian decomposition method for solving linear and nonlinear integral equations. Finally, numerical examples are prepared to illustrate these considerations.