Journal of Applied Sciences and Nanotechnology

Highly porous kaolin ceramics composites were produced by adding space-holder materials during dry pressing. To increase the strength of porous kaolin ceramic composites different ratios of cobalt-nickel ferrite nanoparticles (5, 10, 15, and 20%) were added. The sol-gel auto-combustion method prepared the nano cobalt-nickel ferrite particles (CNF). Space-holder materials were removed by preheating, and solid specimens were produced by sintering. X-ray diffraction (X-RD) and Fourier transform infrared spectroscopy (FT-IR) was used to examine the structural characteristics. Up to 47.05% porosity was achieved when 20% CNF was added to the porous kaolin ceramics composites. The results indicated that the higher percentages of nano CNF 20% decreased linear shrinkage and the loss of ignition by 4.4% and 30.4%, respectively. While increased apparent density and diametrical strength of 1.42 g/cm³, and 9.03MPa respectively. Diametrical strength nanoparticles increased the strength attributed to the formation of a secondary phase in the porous ceramics, improving the crack bridging mechanism.

In this article, the influence of infill ratio and infill pattern on the compressive strength and hardness of 3D printed polylactic acid (PLA) based polymer are studied. The fused deposition modelling (FDM) technique was used to produce the 3D-printed samples. In the current work, three specimens of each type have been tested with selected infill ratios (30, 50, and 70%) and infill patterns (line, gyroid, and trihexagon). A compression test was done using the general-purpose (EN772-1) manual compression testing machine for blocks, cubes, and cylinders by the standard specification (ASTM D695), and hardness shore-D was tested by using a hand-held durometer (Shore Instruments, Type D), by ASTM D2240-05 (2010) type D. The data were collected and processed. The results showed that the 70 percent infill ratio with a linear pattern had the highest compressive strength. On the other hand, the hardness test shows that the maximum hardness value was found at the base side of the specimens.

Using a chemical spray technique, an n-type WO₃ polycrystalline thin film was prepared with optimizing parameters (molarity concentration of 80 mM and a substrate temperature of 350 °C). Study the physical properties of WO₃ thin film via UV-Visible spectroscopy, XRD, Field Emission-Scanning Electron Microscope, Energy Dispersive X-ray Spectroscopy, Atomic Force Microscopy, and current-voltage. Tungsten oxide was deposited on glass surfaces at different molarities ranging from 50–90mM. In the UV-Visible spectrum of the WO₃ thin film, it was found that the transmittance, reflectivity, and energy gap decreased (78%–53%), (9.63%–5.02%), and (3.40eV–2.63 eV), respectively. The X-ray diffraction of the WO₃ film at the optimized was poly-crystalline and had a monoclinic phase, and the preferred orientation (hkl) was 200 at 2 = 24.19. From the image FESEM and EDX, it was found that it has a multi-fibrous network. The average diameter of the fiber is 266 nm, and the ratio of tungsten to oxygen (W/O) is 2.6, with a stoichiometric of 68.6% at the 80 mM concentration. The Atomic Force Microscopy shows that the WO₃ thin layer has a nanostructure. The average surface roughness was 5.3 nm, and the Root Mean Square was 8.6 nm. The WO₃ film had the lowest resistivity value of 2.393 × 108W cm, and the activation energy was 0.298 eV, among the parameter of the current voltage at substrate temperature and concentration optimum.

In this study, using potassium polyacrylate (KPA), polyvinylalcohol (PVA), and zinc chloride as cross-linking agents, successfully synthesized novel superabsorbent polymers. Different weight ratios of KPA and PVA were used to prepare the polymers using polymerization solution. So, polymers with different weight ratios made from PVA and KPA. Superabsorbent polymers (SAPs) were produced using a simple approach at ambient temperature. By comparing absorption peaks, Fourier transform infrared spectroscopy (FTIR) and UV analysis were utilized to investigate the molecular interactions. The morphology of superabsorbent polymers was investigated by scanning electron microscopy (SEM). According to FT-IR, UV, and SEM results, the superabsorbent polymers (Zn-KPA and Zn-PVA) were prepared successfully. A comparison of Zn-KPA and Zn-PVA SAPs was conducted. The effects of cross-linking on water absorption were investigated. The Zn-PVA superabsorbent polymer has a maximum swelling capacity of 407%, while the swelling ratio of the Zn-KPA was 304%. Thus, these prepared superabsorbent polymers could be used for agricultural applications such as water storage. With increasing zinc chloride content and time, superabsorbent polymers’ swelling capacity has considerably improved.

Natural gas has recently drawn considerable attention due to its low emissions upon combustion. Pipeline transmission of natural gas is costly and always encounters different obstacles. Therefore, an effective industrial alternative for the storage and transmission of natural gas is needed. Hydrates, also known as solidified natural gas, have been proven to be a more feasible replacement compared to pipeline transmission, CNG, or LNG. Scientists have introduced promoters to shorten the induction time, increase the storage capacity, and improve the stability of hydrates. Nanostructure materials have demonstrated promising promotion results, suggesting a bright future and a critical step in the industrialization of this technology. Researchers have mainly used pure methane, which is the main component of natural gas, to form hydrates. In this article, the fundamentals of the selection of a nanopromoter, the hydrate formation process, and related calculations are demonstrated. Finally, recent results have been brought together to provide an overview of advances towards the use of nanostructure promoters to tune hydrates for future industrial processes.

Nowadays, sustainable energies can be found by thermal and catalytic pyrolysis of plastic waste. This study uses high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) to investigate thermal and catalytic pyrolysis using a stainless-steel semi-batch reactor at different conditions: Temperatures (350 - 500°C) and residence times (60, 90, and 120 min). The catalysts were undergone to different characterization techniques such as EDX, SEM, and BET that revealed the PR.9 catalyst consists of Cobalt, Molybdenum, and Platinum loaded on Al₂O₃. Whereas, the chemical compositions of Platinum RG-412 catalyst contain Chlorine and Platinum. The SEM analysis showed that the PR.9 catalyst is more active than RG-412 for the degradation of plastics. In addition, the properties of the liquid products like density, API, and viscosity were studied. As a result, the properties of the liquid produced by the plastic pyrolysis were similar that those produced from the petroleum refineries. The API findings declared that almost all of the liquids produced were light products, which contain mainly diesel oil, gas oil, kerosene, and gasoline.

In this work, it was evaluated the wear resistance, hardness, and surface roughness values of resin-based composites that applied in dentistry as restorative materials. The resin composites were made from six types of resin matrixes (A, B, C, D, E, and F) and each one of them has contained different types and ratios of monomers as well as the inorganic nano-fillers (SiO₂, ZrO₂, HA, and Al₂O₃). For each test, thirty specimens were prepared, which were classified into six groups depending on the types of the resin matrix and fillers used in the composites. The results prove that the nanocomposites that have the lowest rate of wear were the group E which was derived from the resin matrix of the group E that has monomers are (BIS-GMA, meth acrylamide, methacrylic acid, and 1-6 hexanediol methacrylate) with values range from 8.11 to 6.11 mm³/mm depending on the filler type material. All prepared composites resin materials (A to F) showed an increase in their hardness values as regards the reference, group D showed the highest hardness value followed by group B while group C was the lowest. The highest mean roughness was shown in groups A and F with 0.82 and 0.79 μm respectively, while the smoother surfaces among all groups were groups B and D which had significantly fewer roughness values of 0.16 and 0.19 μm respectively.

In this work, the physical properties of iron sulfide (FeS₂) thin films deposited by the chemical spray-pyrolysis (CSP) technique were studied.  The thin films are deposited on glass substrates at 200^oC, using FeCl₃ salt with thiourea (NH₂)₂CS as precursors. Structural analysis of X-Ray diffraction manifested that the thin films contain two phases: Marcasite and Pyrite in planes (110), (111) at angles 2θ =26.3°, 2θ =28.3° respectively. Optical properties analysis showed that the prepared iron sulfide thin-films were highly absorbing in the UV-Visible range and the absorption coefficient was in the range of 1.6x10⁵ cm-1 with a relatively low resistivity of about 0.49 (Ω.cm). The calculated activation energy (Ea) was 0.024 eV and the bandgap value was 2.45 eV. Moreover, the FeS2 thin films were also deposited on (CdO) to fabricate a heterojunction photocell. In conclusion, there is the feasibility of preparing low-cost and highly absorbing iron sulfide (FeS₂) thin films for optoelectronic applications with acceptable homogeneity using the spray-pyrolysis technique.

In this research, composite material consist of PMMA and MMA as a matrix materials was prepared and reinforced by natural fibers (sisal fibers) in different concentrations (5, 10%wt). The conventional processing technique for complete dentures was followed to prepare the composite specimens. FTIR test was carried out to reinforcement material (sisal fibers) before and after salinization to determine, whether or not there is chemical bond between reinforcements materials and saline coupling agent. Physical tests such as thermal conductivity, water sorption and solubility were performed on all specimens. The results refer to a highly significant differences in: thermal conductivity, water sorption and solubility of reinforced specimens compared with pure specimens. Increasing the fiber concentration showed a slight decrease in the thermal conductivity of PMMA specimens reinforced with sisal fibers, and increase both water sorption and solubility of composite specimens. FTIR results showed a new absorption band was developed after sialne treatment.

To develop bio-packaging materials, nanocomposite films of cellulose acetate reinforced with titanium dioxide and zinc oxide nanoparticles were prepared, by the casting method at different weight ratios of ZnO nanoparticles (1.5, 2, and 2.5) wt% and a constant weight ratio of 2 wt% TiO₂. ZnO and TiO₂ nanoparticles were tested using scanning electron microscopy (SEM). The mechanical properties (tensile strength and elongation) were improved at a fixed level of Cellulose Acetate+ 2% TiO₂+1.5wt% ZnO loading. Beyond that level of loading, they decreased. The tensile strength was decreased due to some degrees of agglomeration of filler particles above a critical content. Fourier-Transform Infrared Spectroscopy (FTIR) was conducted to reveal the microstructures and chemical composition of as-prepared composite films. The wettability of the films was also determined by the sessile drop method. An increase in contact angle was also observed by the addition of ZnO content from 70.6° to 77.1° compared to pure Cellulose Acetate, which indicated a value of 61.3°. Antibacterial activity against Escherichia coli and Staphylococcus aureus was enhanced after incorporation of ZnO-TiO₂ compared with pure CA. The enhanced wettability and antibacterial activity of the prepared films suggest that they could be used for packaging applications.

Chitosan holds net ionic positive charges, which contribute its ability to chemically bind with negatively charged fats, lipids, metal ions, proteins, and microorganisms. Magnesium oxide (MgO) nanoparticles are important inorganic materials with a wide band-gap used in many applications such as catalysts, antibacterial and medical products. The aim of this study was to investigate the effect of Chitosan (CHT) hydrogel loaded MgO nanoparticles on the bacterial growth. CHT/ poly vinyl alcohol (PVA)/ poly ethylene glycol (PEG) hydrogel was blended with various amounts of MgO nanoparticles. The surface morphology of the obtained blends was investigated by Field Emission Scanning Electron Microscope (FE-SEM). Evidently, surfaces with appropriate roughness were obtained for most of the prepared hydrogels. Fourier Transform Infrared Spectroscopy (FT-IR) and Energy Dispersive X-Ray analysis (EDX) were also included in this paper. Thermal properties of all samples was studied by DSC-TGA curves. The antibacterial activity of the prepared hybrids CHT/PVA/PEG/MgO nanoparticles have performed against gram positive bacteria Staphylococcus aureus (S.aureus) and Streptococcus, as well as gram negative bacteria Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E.coli). In this study, MgO nanoparticles various proportions presented high efficiency towards gram positive microorganisms. High resistance of gram negative bacteria against the final products was extremely detected according to measured inhibition zones which were between (0-9) mm.

The modified Graphene Oxide (GO) synthesis methods used over the past sixty years is contributed mainly to improving its characteristics and increasing its advanced applications. Therefore, in this work, modifying Hummer’s Method via oxidizing graphite flakes using one type of acid (H₂SO₄) was performed without any chemical agents. Also, ultra-sonication and filtration were implemented with optimal parameters (50 kHz frequency during 120 minutes at room temperature 30 ^oC) to prepare GO nanosheets. These procedures improved GO characteristics via analyzing; Particle size, X-ray diffraction pattern (XRD), Ultra-violet visible (UV-vis) absorption, and Scanning Electron Microscopy (SEM). The obtained results showed that the characteristics of GO nano-sheets had met the preparation requirements, such as reducing the average diameter of GO nano‑sheets from 313 nm to 94 nm. Moreover, characterizing the diffraction angle of GO at 9.86^o and the optimal absorption by UV-vis achieved at 230 nm. The synthesis and exfoliation of GO nano-sheets were carried out with fewer impacts of toxicity using distilled water. Finally, this GO synthesis in the lab might be used to make a variety of nanocomposites.

In this paper, Mortar was prepared from medium alumina refractory grog, bricks crashed as a mean material to a particular size, and Iraqi raw (kaolin or bentonite) as binding materials. Refractory bricks were crushed, milled, then sieved to three particle sizes: fine as (1.18 >fine> 0) mm, medium as (2.36 > medium > 1.18) mm, crushed as (400 > coarse > 2.36) mm. Then these particle sizes were mixed with Iraqi raw kaolin or bentonite with selected ratios (10,15,20,30 and 40) %. Specimens were formed by the wetting method, then drying it at laboratory temperature for one day, followed by firing it at 1200 ℃. Results showed that the porosity of specimens decreases when increasing the clay ratio from 3-4% (kaolin or bentonite), and the bond strength between grog and clay increases when increasing the clay ratio from 2-3% (kaolin or bentonite). Also, the diametrical strength increases when increasing the clay ratio from 4-7% (kaolin or bentonite). The thermal shock results showed that K-mortar is better than B-mortar, depending on the results we obtained through the effect of temperature and diametrical strength. The SEM results showed that mortar structure was produced by adding 40% bentonite with small irregularly shaped. The mortar was produced by adding 40% of kaolin which possesses regular mullite crystals. Finally, the results of the test EDS that K-mortar were revealed in showed that there is no adsorption of carbon while B-mortar showed that there is adsorption of carbon atoms.

Conventional concrete is recognized for its high density, which leads to a higher cost of building foundations and columns. Recently, many efforts have been made to produce lower density concrete with acceptable and applicable mechanical properties. One option can reduce the density of the conventional concrete by using partial or total replacement of porcelanite instead of natural gravel.  Porcelanite aggregate concrete can be prepared by adding different ratios of porcelanite and several other additives to the mortar, depending on the required density of the prepared porcelanite concrete. This study aims to assess porcelanite aggregate concrete components, manufacturing methods, and features of porcelanite aggregate concrete. Furthermore, this literature review aims to appraise and provide a complete vision of the testing program, including compressive strength, density, porosity, splitting tensile strength, and water absorption of porcelanite aggregate concrete. Also, this paper focuses on studying the development and applications of the porcelanite aggregate concrete, which will be presented in detail through this study.

In this paper, a homogenous pure Barium Titanate with formula (BaTiO₃) was prepared from pure Barium Carbonate (BaCO₃) and titanium dioxide (TiO₂) using the solid-state reaction technique, were used as raw materials having micro size by mixing of molar ratio [1:1], the powder was calcined at temperatures (900-1350) °C. The solid-State reaction can consider as an attractive process realistic alternative to the expensive wet-chemical route, according to X-ray diffraction, all of the peaks of Barium Titanate powder were perfectly suited to the positions of the peaks of the standard tetragonal phase in the pattern for this process. And with preferred crystalline size for the powder calcined at 1350 °C manifested the best results, where all the peaks indicate the formation of Barium Titanate completely. In addition, each BaTiO₃ Nanopowder was compared to a micro powder that had been manufactured, by conducting x-ray diffraction, diffraction peaks undergo shifting toward higher angle to the high value of 2Ө, and Nano powder particles are smaller than micro powder particles. And this refers to a decrease in lattice parameters, in terms of the peaks of the Nano powder preceding the peaks of the micro powder of BaTiO₃ and that match the result that is obtained by scanning electron microscopy (SEM).

Acinetobacter baumannii is one of the opportunistic nurses responsible for many acquired infections in hospitals due to its ability to resist many antibiotics. This is one of the problems facing hospitals in the world. Identification of the cvaC gene and sequence analysis in Acinetobacter baumannii isolates from various infections, and mutation detection in this gene. From 1^st of September to 30^th of November, 2016, 200 Acinetobacter baumannii isolates were obtained from various clinical samples. Follow fifty isolates from blood, twenty isolates from urinary tract infections, thirty isolates from wound infections, forty isolates from burn infections and twenty-five isolates from stool samples from various hospitals (Central Children's Hospital, Al Karama Hospital, Karkh General Hospital, Al-Ameen Medical City Hospital, Educational Labs, Baghdad Teaching Hospital, Child Protection Hospital, Burns and Wounds Hospital) in Baghdad city. Identification forty isolates confirmed that they belong to Acinetobacter baumannii, including fourteen isolates from a stool sample, nine isolates from blood, eight isolates from burns, four isolates from wound infections, and Respiratory tract infection, , and only one isolate from urinary tract infections sample. Genotypic detection of the cvaC gene of Acinetobacter baumannii showed the presence of this gene in 16 isolates (40%) and Sequencing analysis of cvaC has shown seven genetic mutations and only one mutation has been converted amino acid Alanine to Valine.The amino acid Alanine was changed to Valine in Position 656 at Subject 678, resulting in silent mutations that did not affect protein translation and other mutations that resulted in a change in the amino acid arrangement and protein translation.

This study involves on manufacture of denture base resin with advanced physical properties through the addition of two type of synthetic fibers used as reinforcing materials polypropylene (PP) and Poly acrylonitrile (PAN). In this research, groups of three samples of both PMMA/PP and PMMA/PAN composites were prepared with the selected fiber weight ratios of 1.5, 3.5, 5.5 and 7.5 %Wt. Physical properties such as water absorption, thermal conductivity and density were evaluated under normal conditions. The chemical bond structure was also investigated for all samples using FTIR test. The results showed that when fibers ratio increased until 7.5 %Wt., the water absorption increases, as well for each fiber which was over 0.6% compared to the 0.3% of the neat sample. A noticeable decrease in the thermal conductivity property from 0.33 W/m.K for PMMA/PP and 0.24 W/m.K for PMMA/PAN comparing to 0.46 W/m. K of the neat polymer was revealed. As for the density results, it was found that when the fibers ratios were increased, the sample density slightly decreased and reached 1.09 g/cm³ for PMMA/PP and 1.1 g/cm³ for PMMA/PAN at the maximum fibers rate. FTIR results indicated there was no new peaks appeared after reinforcement with both fibers. This could refer to the good physical bond between the mixtures, no new material formed.

The work idea is finding out how the homogeneity of dielectric strength property in lithium metasilicate glass-ceramic with addition weight percentage increasing of CuO. It prepared four specimens, one without CuO addition lithium metasilicate glass-ceramic LSGC and consists of Li₂O-SiO₂ binary system glass batch with weight percentages 45 wt% Li₂O and 55 wt% SiO₂. It added to the binary system CuO with different weight percentages to prepare the rest three specimens in front of the Li₂O weight percentage decreasing as 1 wt% LC1S, 2 wt% LC2S, and 3 wt% LC3S. The glass batches for four specimens were mixed and used melting-quenching method at temperature of 1195^OC for soaking time 2 hrs. It used platinum crucible (90 Pt-10 Rh) and immediately cooled in the cold water of temperature at 3^OC. This process was repeated twice for all specimens and the produced frit was milled by agate mortar. Addition of P₂O₅ and TiO₂ as nucleating agents with weight percentage 3 wt% P₂O₅ and 1 wt% TiO₂ and prepared compact discs with dimensions 18 diameter × 2.58 thickness mm by the used biaxial hydraulic press with 5 ton for 30 s under pressure. The heat treatment was done for all glass batch compact discs of temperature at 950^OC for 6 hrs as soaking time and breakdown voltage test was done executed 10 different spots in each specimen and Weibull modulus was used to know the homogeneity of dielectric strength property and coincided with Field Emission Scanning Electron Microscopes (FE-SEM) images. It got a good match between Weibull modulus results and FESEM images which indicating that Weibull modulus is the active tool that can be used for knowing the homogeneity of any property. The high average dielectric strength is 9.116 kV/mm for LC1S while the lower average dielectric strength is 7.101 kV/mm for LSGC and this back to more homogeneity and fewer defects in LC1S than LSGC.

The purpose of this study is to optimize the hot corroded pack coated Ni-based super alloy K417G using composite desirability. Pack cementation parameters optimization was performed using quality characteristics of diffusion coatings for pack cementation process, i.e. salt activator, Nano-powders master alloy powder and wt.% Ge. Analysis of variance (ANOVA) was used for observing the most influencing pack cementation parameters on the quality characteristics, i.e. Na₂So₄-6% wt. V₂O₅ (kp1), 100 wt% NaSO₄ (kp₂), and 75 wt. % NaSO₄-25 wt % NaCl (kp₃). A confirmation test was performed after the optimal process parameters were determined using composite desirability analysis. Based on analysis of variance results, the wt.% of Geis the most significant controllable diffusion coating factor for the hot corroded pack coated K417G at optimum setting conditions (A2, B1, C3) i.e. activator (NaCl), master alloy (90Cr-10Al) and wt.% of Ge (2%) according to the quality characteristics. Composite desirability was successfully applied on optimization of hot corroded pack coated K417G using multi-performance characteristics.