Short Multi-Walled Carbon Nanotubes functionalized with OH group (MWCNTs-OH) were used to synthesize flexible MWCNTs networks. The MWCNTs suspension was synthesized using Benzoquinone (BQ) and N, N Dimethylformamide alcohol (DMF) in specific values and then deposited on filter paper by filtration from suspension (FFS) method. Polypyrrole (PPy) conductive polymer doped with metallic nanoparticles (MNPs) prepared using in-situ chemical polymerization method. To improve the properties of the MWCNTs networks, a coating layer of (PPy) conductive polymer, PPy:Ag nanoparticles, and PPy: Cu nanoparticles were applied to the network. The fabricated networks were characterized using an X-ray diffractometer (XRD), UV-Vis. spectrometer, and Atomic Force Microscope (AFM). XRD results revealed that the broadening for the (002) peak decreased after being coated with PPy and increased for the doped samples with MNPs, indicating on decrease in the crystalline size (MWCNTs/PPy) sample and increasing for doped ones with Ag and Cu MNPs. AFM images revealed that the surface roughness of the MWCNTs-OH network decreased after being coated with PPy, PPy: Ag, and PPy: Cu. With the help of AFM and XRD results, the CNTs contain 14 layers, while the inner and outer diameters were 18.2 nm and 27 nm receptivity. The UV-Vis. spectrum of MWCNTs showed several peaks, the highest in the 350 nm range. The coated of MWCNTs greatly affected the absorption spectrum, with many bands appearing between 300 to 450 nm and increasing the absorbance along the overall spectrum. For samples doped with Ag NPs and Cu NPs, a weak absorption peak of the plasmonic resonance frequency of the metallic nanoparticles. Analysis of Raman spectra shows that (ID/IG) ratios for all networks are less than one, which prove that the fabricated networks have few impurities and have good homogeneity. This work aimed to synthesize and characterize a flexible MWCNTs network and develop it by coated with a layer of conductive polymer and metallic nanoparticles for gas sensing application using quick and straightforward preparation methods.
Objective: The aim of this study was to develop a bioadhesive gel of gatifloxacin for the treatment of periodontal diseases.Methods: Periodontal gels of gatifloxacin were prepared using different hydrophilic polymers such as carbopol 940 (CP 940), carboxymethyl cellulose (CMC) and hydroxypropylmethyl cellulose (HPMC) in varied concentrations, either alone or as a combination. The prepared gels were evaluated for their physical appearance, pH, drug content, viscosity, bioadhesiveness and in vitro drug release profile. The influence of the type and the concentration of polymer on the drug release as well as on viscosity and mucoadhesiveness of prepared gels were investigated.Results: The prepared gels showed acceptable physical proper
... Show MoreThis study aims to formulate azithromycin oleogel to locally treat skin infections such as acne vulgaris and skin wound infection. Providing a form of azithromycin that can be administered topically is highly desired to prevent unwanted systemic complications including diarrhea, nausea, and abdominal pain. Additionally, it will avoid first pass metabolism, improves patient acceptance, provides an alternative in nauseated patients, decreases the dose by direct contact with the pathological site, and provides a noninvasive and convenient mode of administration. Furthermore, for treating wound infections, the gel will act as a scaffold biomaterial for wound closure besides its antibacterial effect. Herein, we propose the use of grapeseed oil-b
... Show MoreThe efficiency of Nd:YAG laser radiation in removing debris and smear layer from prepared root
canal walls was studied. Fifty-seven human extracted single rooted anterior teeth were divided into three
groups. A group that was not lased is considered as a control group. The remaining teeth were exposed to
different laser parameters regarding laser energy, repetition rate and exposure time. For the case of the set of
parameters of 7 mJ laser energy, the cleaning was maximum at 3 p.p.s. repetition rate for 3 seconds exposure
time for, the coronal, middle and apical thirds. Above and below this energy level, there was an overdose
(melting) or under dose (no effect). Nevertheless for 10mJ laser energy case, the cleaning effi
In this research the hard chromium electroplating process, which is one of the common methods of overlay coating was used, by using chromium acid as source of chromium and sulphuric acid as catalyst since the ratio between chromic acid and sulphuric acid is (100 : 1) consequently. Plating process was made by applying current of density (40 Amp / dm2) and the range of solution temperature was (50 – 55oC) with different time periods (1-5 hr). A low carbon steel type (Ck15) was used as substrate for hard chromium electroplating. Solid carburization was carried out for hard chromium plating specimen at temperature (925oC) with time duration (2 hr) to be followed with quenching and tempering
... Show MoreCarbon-fiber-reinforced polymer (CFRP) is widely acknowledged as a leading advanced material structure, offering superior properties compared to traditional materials, and has found diverse applications in several industrial sectors, such as that of automobiles, aircrafts, and power plants. However, the production of CFRP composites is prone to fabrication problems, leading to structural defects arising from cycling and aging processes. Identifying these defects at an early stage is crucial to prevent service issues that could result in catastrophic failures. Hence, routine inspection and maintenance are crucial to prevent system collapse. To achieve this objective, conventional nondestructive testing (NDT) methods are utilized to i
... Show MoreHeat transfer applications usually contemplated day‐to‐day are primarily spotlighted on mixed convection, such as solar collector heating arrangements, electronic cooling, and drying processes. Enhancing convection heat transmission in such appliances can be achieved by inserting porous media, inflow loci, and/or line geometry. In the present paper, convection heat transmission inside a vented curved cavity () with an inserted metal foam layer ( PPI and 0.9% porosity) saturated with water was accomplished. The bottom cavity wall was discretely heated at a constant hot temperature, and the curved wall was kept at a constant cold temperature. Governing equations comprising cont
This research deals with the study of top soil electrical conductive regions located within Baghdad City. The research included measuring the dissolved soil material extraction Electrical Conductivity (EC) with an aqueous solution for the top (0-30 cm) soil layer of the study area. As the electrical conductivity values increase by increasing the amount of dissolved salts in principle, we can consider that the aim of this research is to predict the amount and distribution of (soil contamination with salts) which is represented by the (Salt Index), this factor calculated for each soil representative sample taken from the region with a depth of (30 cm). Laboratory (EC) test values measured by the use of solutions (EC) digital meter for the ex
... Show MoreIn this paper, we have extracted Silica from rice husk ash (RHA) by sodium hydroxide to produce sodium silicate. 3-(chloropropyl)triethoxysilane (CPTES) functionalized with sodium silicate via a sol-gel method in one pot synthesis to prepare RHACCl. Chloro group in compound RHACCl replacement in iodo group to prepere RHACI. The FT-IR clearly showed absorption band of C-I at 580 cm-1. Functionalized silica RHACI has high surface area (410 m2/g) and average pore diameter (3.8 nm) within mesoporous range. X-ray diffraction pattern showed that functionalized silica RHACI has amorphous phase .Thermogravemitric analysis (TGA) showed two decomposition stages and SEM morphology of RHACI showed that the particles have irregu
... Show MoreThe flexible joint robot manipulators provide various benefits, but also present many control challenges such as nonlinearities, strong coupling, vibration, etc. This paper proposes optimal second order integral sliding mode control (OSOISMC) for a single link flexible joint manipulator to achieve robust and smooth performance. Firstly, the integral sliding mode control is designed, which consists of a linear quadratic regulator (LQR) as a nominal control, and switching control. This control guarantees the system robustness for the entire process. Then, a nonsingularterminal sliding surface is added to give a second order integral sliding mode control (SOISMC), which reduces chartering effect and gives the finite time convergence as well. S
... Show MoreTrajectory tracking and vibration suppression are essential objectives in a flexible joint manipulator control. The flexible joint manipulator is an under-actuated system, in which the number of control actions is less than the degree of freedom to be controlled. It is very challenging to control the underactuated nonlinear system with two degree of freedom. This paper presents a hierarchical sliding mode control (HSMC) for a rotary flexible joint manipulator (RFJM). Firstly, the rotary flexible joint manipulator is modeled by two subsystems. Secondly, the sliding surfaces for both subsystems are constructed. Finally, the control action is designed based on the Lyapunov function. Computer simulation results demonstrate the effectiveness of
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