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.
This paper presents a study for the influence of magnetohydrodynamic (MHD) on the oscillating flows of fractional Burgers’ fluid. The fractional calculus approach in the constitutive relationship model is introduced and a fractional Burgers’ model is built. The exact solution of the oscillating motions of a fractional Burgers’ fluid due to cosine and sine oscillations of an infinite flat plate are established with the help of integral transforms (Fourier sine and Laplace transforms). The expressions for the velocity field and the resulting shear stress that have been obtained, presented under integral and series form in terms of the generalized Mittag-Leffler function, satisfy all imposed initial and boundary conditions. Finall
... Show Morethe power of the federal supreme court to stop the implementation of the law
China occupies an area of 906 million square km. and lies east Asia. Its population approximately 1,388 people, according to census 2010. China was a global great power for centuries , then shrank its jurisdiction and occupied by European countries and Japan in the 19th century. It regained its strength and independence under the leadership and rule of the Chinese Communist Party since 1949. In the 21st century , the Chinese positions has risen universally due to its achievements in the economic and trade affairs . Nowadays, China became a largest exporting state in the world and a second economic power after USA.
A piezoelectric cantilever beam with a tip mass at its free end is a common energy harvester configuration. This article introduces a new principle of designing such a harvester that increases the generated power without changing the resonance frequency of the harvester: the attraction force between two permanent magnets is used to add stiffness to the system. This magnetic stiffening counters the effect of the tip mass on the efficient operation frequency. Five set-ups incorporating piezoelectric bimorph cantilevers of the same type in different mechanical configurations are compared theoretically and experimentally to investigate the feasibility of this principle: theoretical and experimental results show that magnetically stiffened harve
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This research’s goal is to restore and to revive the jurisprudence of Mother of Believers (Um alMuaamineen) “Um Salmah” "may God bless her", and to highlight her outstanding assimilation and understanding of religion and her conscious thought. The current research is a comparative scientific theoretical study represented in the comparison of jurisprudence of “Um Salamah” with Hadiths of fasting and pilgrimage rules as well as the duration mentioned in jurisprudence of for doctrines( 4 schools of thought )to identify these hadiths with the inclusion and discussion of their evidence.
The current research included two topics: the first one is to identify and introduce
... Show MoreTransgenic plants offer advantages for the manufacture of recombinant proteins with terminal
mannose residues on their glycan chains. So plants are chosen as source of pharmaceutical products and for
the development of alternative expression systems to produce recombinant lysosomal enzymes. In the
present study the sequence of the natural cDNA encoding for the human lysosomal enzyme
glucocerebrosidase (GCD) was modified to enhance its expression in soybean plants. The glucocerebrosidase
gene signal peptide was substituted with that signal peptide for the Arabidopsis thaliana basic endochitinase
gene to support the co-translational translocation into the endoplasmic reticulum (ER), and the storage
vacuol
Hollow core photonic bandgap fibers provide a new geometry for the realization and enhancement of many nonlinear optical effects. Such fibers offer novel guidance and dispersion properties that provide an advantage over conventional fibers for various applications. Dispersion, which expresses the variation with wavelength of the guided-mode group velocity, is one of the most important properties of optical fibers. Photonic crystal fibers (PCFs) offer much larger flexibility than conventional fibers with respect to tailoring of the dispersion curve. This is partly due to the large refractive-index contrast available in the silica/air microstructures, and partly due to the possibility of making complex refractive-index structure over the fibe
... Show MoreWastewater recycling for non-potable uses has gained significant attention to mitigate the high pressure on freshwater resources. This requires using a sustainable technique to treat natural municipal wastewater as an alternative to conventional methods, especially in arid and semi-arid rural areas. One of the promising techniques applied to satisfy the objective of wastewater reuse is the constructed wetlands (CWs) which have been used extensively in most countries worldwide through the last decades. The present study introduces a significant review of the definition, classification, and components of CWs, identifying the mechanisms controlling the removal process within such units. Vertical, horizontal, and hybrid CWs
... Show MoreTRIPS agreement was The first to apply protection by patents. However, this type of protection, which grants exclusive and monopoly rights to patent owners, came at the expense of developing countries which are considered rich in biodiversity and also at the expense of traditional and poor knowledge of modern technologies. The release of new plant varieties has led to the emergence of biopiracy and looting of the rights of developing countries without a license