Bending effects on the transmission of optical signal are investigated on a single mode
optical fiber (SMOF) of 10 m length, core radius of 5 μm and optical refractive index difference
0.003. The bending radii (R) were between 0.08 and 0.0015 m. A great decrease in the amplitude is
shown for radii below 0.01 m. Sudden break down occurs for radii less than 0.0015 m. Birefringence
(B) is difficult to measure for long fibers. Meanwhile, B was found by comparing with calibrated
fiber of the same properties but of length of 0.075 m. The results show an increase in propagation
constant (Δβ) and the decrease in beat length (Lb), and show that bending decreases the critical radius
of curvature (Rc) related to B. The changes induced on the initial phase of the signal are shown for
bending curvatures of radii 0.06, 0.03 and 0.005 m. The linear phase retardation is found to increase
more rapidly for bends of R< 0.05 m. The degree of polarization decreases smoothly for bends of
R>0.01m. Below this curvature, the fluctuation and great instability in the polarization- state of the
output signal are easily detected. All these features are very important in using SMOF in sensitive
optical devices especially in long distance fiber communications.
The advancements in horizontal drilling combined with hydraulic fracturing have been historically proven as the most viable technologies in the exploitation of unconventional resources (e.g., shale and tight gas reservoirs). However, the number of fractures, well timing, and arrangement pattern can have a significant impact on the project economy. Therefore, such design and operating parameters need to be efficiently optimized for obtaining the best production performance from unconventional gas reservoirs. In this study, the process of selecting the optimal number of fractures was conducted on a section of a tight gas reservoir model (based on data from the Whicher Range (WR) tight gas field in Western Australia). Then, the optimal number
... Show MoreA comparison between the resistance capacity of a single pile excited by two opposite rotary machines embedded in dry and saturated sandy soil was considered experimentally. A small-scale physical model was manufactured to accomplish the experimental work in the laboratory. The physical model consists of: two small motors supplied with eccentric mass 0·012 kg and eccentric distance 20 mm representing the two opposite rotary machines, an aluminum shaft with 20 mm in diameter as the pile, and a steel plate with dimensions of (160 × 160 × 20 mm) as a pile cap. The experimental work was achieved taking the following parameters into consideration, pile embedment depth ratio (L/d; length to diameter) and operating freq
... Show MorePesticide poisoning is a serious global public health issue and is responsible for a sizable number of annual fatalities. This study was designed to examine the potentially harmful effects of adult rats being exposed to imidacloprid (IMD) as a nanoparticle by determining the chronic effect of inhalation of (5,10 and 20) mg/kg/b.w. of nano-imidacloprid for a duration of 60 days. The most important biochemical parameters of the serum liver function parameters were aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase ALP, kidney function [blood urea, creatinine, and urea], and oxidative stress parameters (MDA, GSH, and CAT) in all treated groups when
The study aimed to assess Milk Thistle oi reducing the aflatoxin damage and improve the health status of local breed hens. The study was performed on 60 hens aged 35 weeks, weighing 2-2.5 kg of the body was obtained and housed on a private poultry farm in north of Baghdad (Altaji) for a period of 9 weeks from 22 October until 22 December 2020. Hens were divided to three treatments (20 hens). The first was fed a basal diet free of aflatoxin. The 2nd fed on a contaminated diet with aflatoxin (14.6 ppb) while the 3rd fed as in the 2nd with 0.5% of Milk Thistle oil /kg feed. A 5 hens from each group were slaughtered at the end of the trial for the histopathological inspection of liver, spleen and intestine tissues to evaluate the harmfu
... Show MoreThe goal of the current study was to research the changes in hematological parameters: WBC count, RBCs count, Hb, PCV, neutrophil, lymphocyte, and monocyte in albino mice infected with Aspergillus fumigatus by intraperitoneal injection after induced immunosuppression by intraperitoneal injection of cortisone. The current research also examined an attempt to reduce the infection load by treating Solanum aculeastrum. The result shows higher decreased significance (P≤0. 05) in RBCs, Hb, and PCV after being infected with A. fumigatus 7. 1 ± 0. 8, 11. 3 ± 0. 5 and 41. 5 ± 2. 4, respectively, while the total WBC count, neutrophil, lymphocyte, and monocytes were increased significantly (P≤0. 05) after treatment with S. aculeastrum i
... Show MoreEpoxy (EP) – Silica (SiO2) composites are well known composites used in microelectronic industry . So it is important to study their dielectric behavior under different conditions such as
the presence carbon black (UV absorber) and immersion in the water for 30 days .
Dielectric properties were calculated over the frequency range 102 – 106 Hz for epoxy composites with different weight % of micrometer 1.5μm SiO2 particles (60%, 65% and 70wt%) modified with 0.5wt% silane coupling agent to improve adhesion between EP and SiO2 phases .
This work aim to prepare Ag/R6G/PMMA nanocomposite thin
films by In-situ plasma polymerization and study the changes in the
optical properties of fluorophore due to the presence of Ag
nanoparticles structures in the vicinity of the R6G laser dye. The
concentrations of R6G dye/MMA used are: 10-4M solutions were
prepared by dissolving the required quantity of the R6G dye in
MMAMonomer. Then Silver nanoparticles with 50 average particles
size were mixed with MMAmonomer with concentration of 0.3, 0.5,
0.7wt% to get R6G silver/MMA in liquid phase. The films were
deposited on glass substrates by dielectric barrier discharge plasma
jet. The Ag/R6G/PMMA nanocomposite thin films were
characterization by UV-Visible
In this work, the plasma parameters (electron temperature and
electron density) were determined by optical emission spectroscopy
(OES) produced by the RF magnetron Zn plasma produced by
oxygen and argon at different working pressure. The spectrum was
recorded by spectrometer supplied with CCD camera, computer and
NIST standard of neutral and ionic lines of Zn, argon and oxygen.
The effects of pressure on plasma parameters were studied and a
comparison between the two gasses was made.
The seedlings of vegetables are exposed to stress states, especially through the first period, due to injuring their roots by transplanting or heavy rain , so it is necessary to provide an available nutrient to recover the growth and increase their early yield, which means more income for farmers. In this regard, an experiment was conducted in the College of Agricultural Engineering Sciences, Agriculture Faculty, University of Baghdad, Iraq to study the effect of different types and concentrations of mineral fertilizers as starter solutions by using high nitrogen (N), high phosphorus (P) and neutral fertilizers (Q) at three levels which were 4 g/l (S1), 8 g/l (S2) and 12 g/l (S3) on broccoli growth and yield. The results showed tha
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