Polyimide/MWCNTs nanocomposites have been fabricated by solution mixing process. In the present study, we have investigated electrical conductivity and dielectric properties of PI/MWCNT nanocomposites in frequency range of 1 kHz to 100 kHz at different MWCNTs concentrations from 0 wt.% to 15 wt.%. It has been observed that the electrical conductivity and dielectric constants are enhanced significantly by several orders of magnitude up to 15 wt.% of MWCNTs content. The electrical conductivity increases as the frequency is increased, which can be attributed to high dislocation density near the interface. The rapid increase in the dielectric constant at a high MWCNTs content can be explained by the formation of a percolative path of the conducting network through the sample for a concentration corresponding to the percolation threshold. The high dielectric constant at a low frequency (1 kHz) is thought to originate from the space charge polarization mechanism. I-V characteristics of these devices indicate a significant increase in current with an increase in multi-walled carbon nanotube concentration in the composites. The SEM images show improved dispersion of MWCNTs in the PI matrix; this is due to the strong interfacial interactions.
This study aimed to formulate carboxymethyl cellulose (CMC)–eggshell powder (ESP) composite coatings ( , , and ) and evaluate their efficacy in extending table egg shelf life and preserving quality parameters compared to an uncoated control ( ). Egg weight parameters, interior egg quality, component proportions, and bacterial counts of shell eggs stored under refrigeration for up to 8 weeks. Coating treatments significantly increased total egg weight and shell thickness at (P<0.05), with and recording the highest initial values. Although weight loss and weight loss percentage were non-significant during week 1, significant weight loss emerged by week 2 and scaled proportionally through weeks 4 and 8. The uncoated control (
... Show MoreThe reason behind choosing this topic " internal marketing (IM) of human resource management (HRM)" is to highlight the advantages of using IM in the organization framework. The problem of the research paper lies in not paying enough attention to employees genuine needs as they interact with each other in the sake of organization prosper. This research paper can be used as indictor to expose the weaknesses that the organization encounters daily. The current research paper attempts at examining the possibility of developing philosophy of internal marketing of human resources and its most practices, empowering staff, training courses, motivations and recognitions, and within departments communication, in order to reach targeted res
... Show MoreThe technical of Flame Thermal Spray had been used in producing a cermet
composite based on powders of stabilized zirconium oxide containing amount of
Yatteria oxide (ZrO2- 8Y2O3) reiforced by minerals powders of bonding material
(Ni-Cr- Al- Y) in different rates of additions (25, 35, 50) on stainless steel base type
(304) after preparing it by the way of Grit Blasting.
Before heat treatment, the coated cermet layers were characterized for porosity
and electric resistivity. All samples were heat treated in vacuum furnace at different
temperature and times. The physical tests had been operated after heat treatment
and gave best results especially porosity, which found to be reduced dramatically
and producing hig
The efficient behavior of a low-concentrating photovoltaic-thermal system with a micro-jet channel (LCPV/T-JET) and booster mirror reflector is experimentally evaluated here. Micro-jets promote the thermal management of PV solar cells by implementing jet water as active cooling, which is still in the early stages of development. The booster mirror reflector concentrates solar irradiance into solar cells and improves the thermal, electrical, and combined efficiencies of the LCPV/T-JET system. The LCPV/T-JET system was tested under ambient weather conditions in the city of Bangi, Selangor, Malaysia, and all data was recorded between 10:00 a.m. and 4:00 p.m. Parametric studies were conducted to compare the performance of the LCPV/T-JET system
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For criminal investigations, fingerprints remain the most reliable form of personal identification despite developments in other fields like DNA profiling. The objective of this work is to compare the performance of both commercial charcoal and activated carbon powder derived from the Alhagi plant to reveal latent fingerprints from different non-porous surfaces (cardboard, plain glass, aluminum foil sheet, China Dish, Plastic, and Switch). The effect of three variables on activated carbon production was investigated. These variables were the impregnation ratio (the weight ratio of KOH: dried raw material), the activation temperature, and the activation time. The effect factors were investigated using Central Composite Design
... Show MoreFor criminal investigations, fingerprints remain the most reliable form of personal identification despite developments in other fields like DNA profiling. The objective of this work is to compare the performance of both commercial charcoal and activated carbon powder derived from the Alhagi plant to reveal latent fingerprints from different non-porous surfaces (cardboard, plain glass, aluminum foil sheet, China Dish, Plastic, and Switch). The effect of three variables on activated carbon production was investigated. These variables were the impregnation ratio (the weight ratio of KOH: dried raw material), the activation temperature, and the activation time. The effect factors were investigated using Central Composite Design (CCD) softwa
... Show MoreThis current study was built on creating four electrodes based on molecularly imprinted polymers (MIPs). As the template using Cefalexin (CFX), 1-vinyl imidazole (VIZ) and vinyl acetate (VA) as monomer, and N, N-methylene bis acrylamide (MBAA) as cross-linkers and benzoyl peroxide as the initiator, two MIPs were prepared. The same composition was used in non-impressed polymers (NIPs) preparation, but without the template (Cefalexin). For the membranes preparation, numerous plasticizers, such as tri-oly phosphate (TOP) and di-octyl phthalate (DOP), were used in the PVC matrix, slop, detection limit, lifetime, and linearity range of CFX-MIPs electrodes are characteristics &nb
... Show MoreGas sensors are essential for detecting noxious gases that have a detrimental effect on people's health and welfare. Carbon quantum dots (CQDs) are the fundamental component of gas detectors. CQDs and graphene (Gr) were prepared using the electrochemical method. The gas sensitivity of these materials was evaluated at different temperatures (150, 200, 250 °C) to assess their effectiveness. Subsequently, experiments were conducted at different temperatures to ascertain that the combination of CQDs and Gr, with various percentages of Gr and CQDs, exhibited superior gas sensitization properties compared to CQDs alone. This was evaluated based on criteria such as sensitivity, recovery time, and reaction time. Interestingly, the combination was
... Show Morehe effect of different cultural conditions on production of bioemulsifier from Serratia marcescens S10 was determined; different carbon and nitrogen sources were used such as: different oils include: edible (vegetable) oils (olive oil, sesame oil, sun flower oil and corn oil) and heavy oils (oil 150, oil 60, oil 40) as carbon sources and (NH4Cl, casein, (NH4)2SO4, peptone, tryptone, gelatin and yeast extract) as nitrogen sources were added to production media. Bioemulsifier was estimated by measuring the surface tension (S.T), emulsification activity (E.A) and emulsification index (E24%). The best results of bioemulsifier production from Serratia marcescens S10 were obtained at pH8 and incubated at 37ºC for 5days, using sesame oil
... Show MorePreviously, many empirical models have been used to predict corrosion rates under different CO2 corrosion parameters conditions. Most of these models did not predict the corrosion rate exactly, besides it determined effects of variables by holding some variables constant and changing the values of other variables to obtain the regression model. As a result the experiments will be large and cost too much. In this paper response surface methodology (RSM) was proposed to optimize the experiments and reduce the experimental running. The experiments studied effects of temperature (40 – 60 °C), pH (3-5), acetic acid (HAc) concentration (1000-3000 ppm) and rotation speed (1000-1500 rpm) on CO2 corrosion performance of t
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