Photonic crystal fiber interferometers (PCFIs) are widely used for sensing applications. This work presented solid core-PCFs based on Mach-Zehnder modal interferometer for sensing refractive index. The general structure of sensor was applied by splicing short lengths of PCF in both sides with conventional single mode fiber (SMF-28).To apply modal interferometer theory collapsing technique based on fusion splicing used to excite higher order modes (LP01 and LP11). A high sensitive optical spectrum analyzer (OSA) was used to monitor and record the transmitted wavelength. This work studied a Mach-Zahnder interferometer refractive index sensor based on splicing point tapered SMF-PCF-SMF. Relation between refractive index sensitivity and taper waist diameter were studied through simulation and experiments. The experimental and simulation results show that sensitivity would be increased with a decrease of taper waist diameter. The response of the PCFI is observed for a range of refractive index values from (1.33 to 1.38). When the length of PCF was (4)cm with different taper waist diameter (125,107,90,60)μm, the maximum refractive index sensitivity of (20 pm / RIU) was achieved. When taper waist diameter became (60)μm, the rate of increase in sensitivity was 12.4% compared with the taper waist diameter (125)μm.
Positron annihilation lifetime (PAL) technique has been employed to
study the microstructural changes of polyurethane (PU), EUXIT 101
and epoxy risen (EP), EUXIT 60 by Gamma-ray irradiation with the
dose range (95.76 - 957.6) kGy. The size of the free volume hole and
their fraction in PU and EP were determined from ortho-positronium
lifetime component and its intensity in the measured lifetime spectra.
The results show that the irradiation causes significant changes in the
free volume hole size (Vh) and the fractional free volume (Fh), and
thereby the microstructure of PU and EP. The results indicate that
the γ-dose increases the crystallinity in the amorphous regions of PU
and increas
Recently, environmental noise has arisen from various sources, such as those from exhaust mufflers of combustion engines found in cars, trucks, or power generators, which produce significant noise during their operation. Controlling the radiated noise from these mufflers is a major factor in improving acoustic comfort and minimizing the impact on the surrounding communities. Numerous research has been presented for this reason by modification of the internal structure of the exhaust muffler. The main objective of this work is to reduce the noise level emitted from exhaust mufflers. This can be achieved by adjusting structure parameters to attenuate the surrounding environment's radiated noise. Analysis of pressure-wave propagation h
... Show MoreAbstract: Coriandrum sativum leaves are used in folk medicine to treat several diseases such as digestive system disorder, diabetes, and hyperlipidemia. This study was designed to investigate the effect of aqueous extract of Coriandrum sativum on the structure and function of kidney, 30 males of white Swiss mice Mus musculus were divided randomly to three groups with 10 mice in each group. Animals of first group (control group) had been given orally 0.1 ml of tap water, animals in the second group had been treated orally with 0.1 of single dose (125 mg/Kg b. w./day) of C. sativum leaves extract and animals in the third group has been treated orally with 0.1 ml (250mg/Kg. b. w./day) of the same extract for 30 days. At the end of experiment,
... Show MoreThe effect of metal nanoparticles on the anaerobic digestion of sludge and the sludge bacterial community are still not well-understood, and both improvements and inhibitions have been reported. This study investigated the impact of 2, 10, and 30 mg/g TS silver and copper oxide nanoparticles (AgNPs and CuONPs) on the mesophilic anaerobic digestion of sludge and the bacterial community structure. The reactors were monitored for changes in tCOD, sCOD, TS, VS, biogas generation, and cell viability. Also, the relative abundance and taxonomic distribution of the bacterial communities were analyzed at the phylum and genus levels, including the genera involved in anaerobic digestion. Both AgNPs and CuONPs exhibited some inhibition on anaer
... Show MoreThe current research seeks to identify the most important humanitarian issues of a sacred and very important group in all the heavenly religions and human societies, namely the elderly, to identify their significant problems and health problems, and What are the effects of these problems on their mental health and which is the ultimate goal of human resources in All parts of the world? The study relied on what is available from the sources in the literature starting from the messages of heaven and the Islamic religion followed with humanitarian, social, legal and psychological postulates. The research included four systematic chapters included the definition research and identification of the problem, importance, objectives and terminolo
... Show MoreIdentifying the total number of fruits on trees has long been of interest in agricultural crop estimation work. Yield prediction of fruits in practical environment is one of the hard and significant tasks to obtain better results in crop management system to achieve more productivity with regard to moderate cost. Utilized color vision in machine vision system to identify citrus fruits, and estimated yield information of the citrus grove in-real time. Fruit recognition algorithms based on color features to estimate the number of fruit. In the current research work, some low complexity and efficient image analysis approach was proposed to count yield fruits image in the natural scene. Semi automatic segmentation and yield calculation of fruit
... Show MoreAlzheimer’s disease (AD) is an age-related progressive and neurodegenerative disorder, which is characterized by loss of memory and cognitive decline. It is the main cause of disability among older people. The rapid increase in the number of people living with AD and other forms of dementia due to the aging population represents a major challenge to health and social care systems worldwide. Degeneration of brain cells due to AD starts many years before the clinical manifestations become clear. Early diagnosis of AD will contribute to the development of effective treatments that could slow, stop, or prevent significant cognitive decline. Consequently, early diagnosis of AD may also be valuable in detecting patients with dementia who have n
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