Higher Surface Roughness Values Research Articles

Effects of graphene oxide and silane‐grafted graphene oxide on chitosan packaging nanocomposite films for bread preservation

AbstractThis study aims to investigate the dual effects of (3‐aminopropyl)triethoxysilane (APTES)‐grafted‐GO (A‐g‐GO), and titanium dioxide (TiO2) on the novel chitosan (CS) packaging nanocomposite films developed via the solution‐casting method. The chemical properties of GO and A‐g‐GO were assessed using FTIR and XRD. Subsequently, the chemical, structural, and physical attributes of all chitosan packaging nanocomposite films were analyzed through FTIR, XRD, TGA, DSC, AFM, water contact angle analysis, and food packaging tests. Successful silanization of GO by APTES was first confirmed. The highest surface roughness value was observed in the CS/A‐g‐GO/TiO2 film (16.574 nm) compared to pristine CS and other nanocomposite films. Incorporating GO into the CS matrix improved its thermal stability, suggesting robust bonding between GO and the polymer matrix. The addition of A‐g‐GO slightly decreased the contact angle value (107.7° for CS/A‐g‐GO), whereas TiO2 increased contact angles (117.3° for CS/GO/TiO2 and 119.4° for CS/A‐g‐GO/TiO2), suggesting a more hydrophilic structure with GO and A‐g‐GO and a more hydrophobic structure with TiO2. Bread samples showed no structural distortion over 40 days. Therefore, the dual impacts of A‐g‐GO and TiO2 on the pristine CS film imply that the resulting CS/A‐g‐GO/TiO2 film exhibits potential as an exceptionally efficient packaging material for prolonging the freshness of bread.

Investigation of open air and under water laser surface texturing on surface roughness and wettability of Al-Mg alloy

Aluminum-Magnesium (Al-Mg) alloy is widely used in aerospace and marine related applications due to its high corrosion resistance, tensile strength and ductility properties. However, due to hydrophilic nature, its applications are restricted in areas where water absorption may cause problems like corrosion. In this research work, high speed laser texturing was carried out on Al-Mg alloy (AA5754) to improve hydrophobic properties of the material surface. Four different types of pattern, namely lines, grids, concentric circles and concentric rectangles were created on the material surface using a nanosecond fiber laser. Scanning speed was varied at two levels i.e., 500 mm/s and 1000 mm/s. Line density of texture designs was also varied at two levels of 10 lines per mm and 15 lines per mm. The texturing process was carried out in two different processing environment namely open air and in underwater condition. Distilled water with 1 mm thickness above the surface was used during underwater texturing condition. Surface morphology, surface roughness and wettability of all the surfaces were studied for all the experimental conditions. It was observed that lower scanning speed of 500 mm/s resulted in higher values of surface roughness and contact angles. Also, larger texture density leads to lower surface roughness and contact angles for all the pattern designs. Among all the studied texture patterns, grid structures, textured at 500 mm/s of scanning speed resulted in largest surface roughness and surface hydrophobicity.

Surface roughness of different types of resin composites after artificial aging procedures: an in vitro study

BackgroundThe temperature changes, chemical agents, and brushing activity that resin composite restorations are exposed to in the oral environment can cause changes in surface roughness. In this study, the aim was to investigate in vitro the clinical one-year surface roughness changes of different types of composites (flowable or conventional) from the same companies by subjecting them to immersion in solutions, brushing, and thermal cycling procedures to simulate intraoral conditions.MethodsFour different resin composite brands were included in the study using both their conventional (Charisma Smart, 3M Filtek Ultimate Universal, Omnichroma, Beautifil II) and flowable resin composites (Charisma Flow, 3M Filtek Ultimate Flowable, Omnichroma Flow, Beautifil Flow Plus F00), giving 4 groups with 2 types of resin composite in each. 40 samples were prepared for each group/resin type, for a total of 320 samples. After initial surface roughness measurements by a mechanical profilometer, the samples were divided into 4 subgroups (n = 10) and immersed in solutions (distilled water, tea, coffee, or wine) for 12 days. The samples were then subjected to 10,000 cycles of brushing simulation and 10,000 cycles of thermal aging. Surface roughness measurements were repeated after the procedures. For statistical analysis, the 3-way analysis of variance and the Tukey test were used (p < 0.05).ResultsIt was concluded that composite groups and types had an effect on surface roughness at time t0 (p < 0.001). At time t1, the highest surface roughness value was obtained in the Beautifil-conventional interaction. When the surface roughness values between time t0 and t1 were compared, an increase was observed in the Beautifil II and Beautifil Flow Plus F00, while a decrease was observed in the other composite groups.ConclusionComposite groups, types, and solutions had an effect on the surface roughness of resin composites. After aging procedures, it was concluded that the Beautifil group could not maintain the surface structure as it exceeded the threshold value of 0.2 μm for bacterial adhesion.

Surface roughness estimation using vibration characteristics extracted by variational mode decomposition in turning

This study presents an approach that combines variational mode decomposition (VMD) and relevance vector machine (RVM) as a prediction technique for surface roughness during turning. The method helps machinists detect irregularities during machining, such as looseness in machine parts or tool wear. The study uses work hardened EN8 steel and extracts vibration signal features into five modes. PSO optimized RVM prediction models are developed using these modes with and without combining cutting parameters. The most sensitive mode is selected for accurate surface roughness prediction. The results show that the first mode of decomposition when combined with cutting parameters provides the least mean square error of 0.1095. Surface roughness was found to be primarily influenced inversly by cutting speed and directly by feed rate respectively. The signal with high surface roughness value has high amplitude noise scattered over the large frequency range. The first decomposed mode of vibration signal increases noise with a large amplitude as surface roughness increases. The approach can be integrated into a microcontroller to regulate machine settings based on vibration data.

Analisis Metode Anodizing Aluminium dengan Variasi Kuat Arus sebagai Material Velg Kendaraan

Aluminum Alloy 6061 is widely used in various engineering applications, including automotive vehicle wheels. The selection of aluminum alloy wheels involves aspects such as corrosion resistance. To enhance corrosion resistance, there are several methods, one of which is anodizing. Anodizing is a process that involves an electrolytic coating process that transforms the surface of aluminum into aluminum oxide (Al2O3), which the main process of aluminum anodizing requires a solution of sulfuric acid, chromic acid, or a mixture of sulfuric acid and oxalic acid. The sulfuric acid used must be concentrated acid, and acid is an oxidizing substance. The thickness of the oxide is approximately twice the thickness of the lost aluminum. The purpose of this research is to determine the characteristic such as surface roughness values, corrosion rates, and changes in morphology in Aluminum 6061 after undergoing anodizing. In this study, various current strengths were used, namely 0.75 Amperes, 1.5 Amperes, 2.25 Amperes, and 3 Amperes. The highest surface roughness value was obtained at 0.447 μm in the third specimen of the 0.75 Ampere variation, while the lowest was 0.075 μm in the first specimen of the 3 Ampere variation. The highest corrosion rate was observed in the 0.75 Ampere variation, with a rate of 17.724004 mpy, and the lowest was 0.0731653 mpy in the 3 Ampere variation. SEM results show that, in general, Aluminum 6061 tends to have a bright gray color, which is a surface that has been coated by cathode.

The effect of different liquids on the surface roughness and color stability of single shade and nanohybrid resin composites: An AFM and SEM analysis.

The aim of this study is to evaluate the surface roughness (SR) and color changes of single-shade and nanohybrid resin-based restorative materials (RBC) after immersion in liquids at different pH values. For RBCs, a total of 120 specimens, 30 for each material, were prepared using 10 mm diameter and 2 mm thick molds. For flowable bulk fill RBC, a total of 40 specimens, 10 for each material, were prepared using 10 mm diameter and 4 mm thick molds (n = 10). After initial color and SR measurements, samples were stored in the liquids for 14 days and all of the measurements were repeated on 14th days. Scanning electron microscopy and atomic force microscopy analyzes were performed in all groups. When SR results are examined; among all liquids, the highest SR value was observed in the Carisma Diamond One (CDO) group, while the lowest SR value was observed in the Omnichroma Flow Bulk (OMF) group (p < .05). When the color changes (ΔE) results are examined; it was observed that CDO group had highest color change and OMF group had the lowest values. It has been observed that among the liquids, the liquids that affect the ΔE values of the materials the most are coffee and cola. When the ΔE values of the subgroups of the materials were examined, there was a statistically significant difference in all subgroups of RBCs (p < .05). While acidic liquids increased the SR of RBCs, coffee more affected the color change of RBCs. RESEARCH HIGHLIGHTS: Clinicians should keep in mind that the RBCs tested may change their surface properties and colors when exposed to various liquids. People who have RBCs should pay attention to the consumption of acidic and highly pigmented liquids.

Evaluating the Effect of Different Mouthrinses on Properties of the Enamel and Dental Composite Surfaces

This study investigated the effects of different solutions (artificial saliva, Listerine Cool Mint-alcohol containing and Colgate Plax-alcohol free) on the nanohardness, elastic modulus and surface roughness of enamel surface and composite materials (Admira Fusion, Clearfil Majesty Esthetic and Mosaic Universal). Specimens of 2 mm depth and 5 mm diameter were stored in solutions for 12 h at 37�C. Baseline and final measurements were obtained using a HYSITRON TI 950 TriboIndenter testing machine. The applied force to each specimen increased from 0 to 1000 �N. For SEM images, one sample in each group was covered with a thin layer of mix of gold and palladium using a sputter coater (Quorum Q150R ES, UK). Scanning electron microscopy (SEM) images were taken at 5000� magnifications to evaluate the surface morphology. Statistical analysis for hardness, elastic modulus and roughness was performed by Two-way ANOVA, Benferroni and Tukey HSD at a significance level 0.05. The results of this study showed that the highest value of surface roughness and lowest hardness and elastic modulus were presented by Admira (p[0.001). Listerine caused significantly increased surface roughness (p[0.001) and decreased hardness and elastic modulus parameters (p[0.001). The mouthrinse containing alcohol caused more significant changes in the nanohardness, elastic modulus, surface roughness values of enamel and composite surfaces.

Effect of pulse time (Ton), pause time (Toff), peak current (Ip) on MRR and surface roughness of Cu–Al–Mn ternary shape memory alloy using wire EDM

Shape memory and super elasticity are two outstanding properties of Cu–Al–Mn SMAs together with additional copper-based shape memory alloys that make them superior to NiTi alloys. It's quite hard to machine Cu–Al–Mn SMA. The machinability properties of Cu–Al–Mn SMAs during Wire Electrical Discharge Machining (WEDM) were experimentally investigated using molybdenum wire as the electrode material. Material Removal Rate (MRR) and Surface Roughness (SR) are two machining qualities that are studied in relation to the combinational values of pulse time (Ton), pause time (Toff), and peak current (Ip), which are selected as the changeable input process factors. From the experimental investigation, it was found that both MRR and Ra values were increased with an increase in pulse on time(Ton), pulse off time(Toff), and peak current (IP)values. Because the wire electrode contains maximum current under these conditions, it is easy to remove more material at the tool and work material interface, resulting in moderate surface finish. Surface quality was higher on samples machined at low energy input than it was on samples machined at high energy input. This SEM micrograph clearly shows that a lower pulse on time produces a superior surface quality.SEM images and the analysis of the machined surface morphology on the surface of the CAM7 alloy clearly showed that the machined surface of the alloy had a lower surface roughness value at a lower Ip-2A and was associated with a higher surface roughness value at a higher Ip-6A, as well as a lot of uncleared debris and blow holes.

PENGARUH JENIS MEDIA PENDINGIN TERHADAP GETARAN DAN NILAI KEKASARAN PERMUKAAN PADA PEMBUBUTAN MATERIAL BAJA AISI 1045

The coolant in the turning process functions to stabilize the temperature in the cutting process in addition to the temperature on the workpiece as well as the temperature on the tool, where an increase in temperature will certainly cause changes in mechanical properties. This research aims to find a correlation between surface roughness and vibration with variations in cooling in the AISI 1045 steel turning process. The research method for the AISI 1045 steel turning process is with a depth of cut 1 mm and a feed rate of 0.21 mm/rev and a rotation of 1,160 rpm, cooling using with variations, without cooling, dromus, and air coolant. Vibrations are detected in the tool during the turning process using a vibration meter and the surface roughness results are measured using a surface roughnees tester. The results show that the highest vibration value was produced in the process without cooling at 4.8 mm/s2, then the coolant cooler produced a vibration value of 4.3 mm/s2, and the dromus cooler produced the lowest vibration value at 3.9 mm/s2. Meanwhile, the highest surface roughness value was produced in the turning process without cooling at 6.247 µm, then the coolant cooling media produced a surface roughness value of 5.442 µm, and the dromus cooler produced the lowest surface roughness value at 4.848 µm. The vibration value and surface roughness show that there is a correlation that the higher the vibration, the higher the surface roughness value produced by turning AISI 1045 steel.

An In Vitro Study of the Abrasive Potential of Various Toothbrushes on the Surface of Aligner Attachments.

Background Attachments play a vital role in aligner-led orthodontic therapy, firstpassivelythrough retention of the appliance and secondly, through bringing about tooth movement, by virtue of its active surfaces, to achieve treatment goals. Additionally, irregularities on the surface of attachments attract plaque adhesion.Thus the effect of brushing with different toothbrushes on the surface of attachments is an important factor to study. This would allow clinicians to better advise patients who are undergoing aligner therapy. Four types of brushes are available commercially, namely hard, medium, soft, and ultra-soft. This study analyses the interaction between the kind of toothbrush used and the wear of the surface of the aligner attachment, to understand the impact of a toothbrush on the attachment. Aim To observe the surface wear and change in the shape of the aligner attachment on brushing with four varying hardness of toothbrush bristle (ultra-soft, soft, medium, and hard) over six months to three years. Material and methods One attachment was bonded to the buccal surface of extracted premolars. One tooth with attachment was subjected to SEM analysis and the rest were divided into four groups of five teeth each, based on the type of toothbrush to be used. Brushing with hard, medium, soft, and ultra-soft toothbrushes was carried out in a brushing simulator in two cycles simulating six months, one year, 18 months, and three years of brushing. A contact profilometer was used to evaluate surface roughness before and after brushing and pre- and post-surface roughness values were compared to quantitate changes after which SEM analysis was carried out for qualitative assessment of the surface of the samples. The Shapiro-Wilks test was applied to evaluate the normality of the data, followed by the one-way ANOVA, and statistical significance was applied at p<0.05. Results At six months, the samples brushed with the medium toothbrush showed the least surface roughness (0.2±0.192) and those brushed with the ultra-soft toothbrushes showed the highest surface roughness (1.9±0.159). At one year, the samples brushed with the soft toothbrush showed the least surface roughness (0.46 ±0.31) and those brushed with the ultra-soft toothbrushes showed the highest surface roughness (2.12 ±0.12). At the 1.5-year point, the surface roughness of the samples was lowest in the ultra-soft toothbrush group (0.43±0.39) and the highest in the soft toothbrush group (1.6± 0.41). At the three-year point, the surface roughness of the samples was lowest in the ultra-soft toothbrush group (0.28 ± 0.17) and the highest in the medium toothbrush group (1.6 ± 0.31). Conclusion Ultra-soft toothbrushes have a high abrasive potential, as seen by higher surface roughness values over six months and one year. Morphometric changes were the most noticeable for attachments brushed by hard-bristled toothbrushes and medium-bristled brushes.

Comparison of volumetric loss and surface roughness of composite dental restorations obtained by additive and subtractive manufacturing methods

Statement of problemPermanent crown materials produced with new generation additive manufacturing and traditional subtractive manufacturing materials have not been compared in terms of wear resistance. PurposeThis study aims to compare the volumetric loss related to wear and resulting surface roughness after aging in a chewing simulator between resin nano ceramics produced with milling technique and permanent crown materials produced with three dimensional (3D) printing. Materials and methodsThree different hybrid composite-ceramic (HCC) (The three materials are GC: Cerasmart, VE: Vita Enamic, and GV: Grandio Voco.) and one 3D printed definitive crown resin (FormLabs Permanent Crown Resin) were investigated before aging (n:8), the surface roughness of all samples was measured with a profilometer, and 1 randomly selected sample from each subgroup was imaged with scanning electron microscope (SEM). 3D scans of each sample were obtained with a desktop scanner. Thermomechanical aging was performed using a chewing simulator. Four hundred thousand cycles were completed under a vertical occlusal force of 49 ± 0.7 N with a thermal cycle of 1.7 Hz 5–55° and with a dwell time of 120 s, mimicking 2 years of aging. The imaging procedures were repeated, and the change in surface roughness was evaluated. 3D images were also overlapped, and the volumetric loss was calculated with the relevant inspector software. The data obtained were analyzed by two-way ANOVA (p < 0.05). ResultThe results showed significant statistical differences for both parameters (p > 0.05). The highest volumetric loss was found in the GV group while the lowest volumetric loss was in the VE group. The highest surface roughness values were observed in the GV group, while the lowest values belonged to the VE one. ConclusionOf the restorative materials evaluated, the VE group is suitable for long-term restorations, whereas the GV one is suitable for medium-term restorations. It is promising in terms of 3D printing technologies that the 3D material gives comparable results with the GV group. Clinical i̇mplicationAdditive manufacturing techniques are a successful method that accelerates the manufacturing process. Permanent crown resins are promising alternatives to conventional production.

Comparison of the Effect of the Same Polishing Method on the Surface Roughness of Conventional, CAD/CAM Milling and 3D Printing Denture Base Materials

Objective: The aim of this study was to evaluate the effect of both the same polishing method and those with and without thermal aging on the surface roughness of conventional, CAD/CAM milling and 3D printing denture base materials.&#x0D; Materials and Methods: A total of 30 round shaped specimens were obtained by 3 different methods (n=10): Conventional, CAD/CAM milling and 3D-Printing. After applying the same polishing technique to all groups, surface roughness values were measured. Profilometer device was used for surface roughness measurement. Then, after the thermal aging of all samples, surface roughness values were measured and the roughness values between no-thermocycling and thermocycling were compared. Tukey, Mann Whitney U and Kruskal Wallis tests were used statistically. P values of ≤ 0.05 were considered significant. &#x0D; Results: As a result of the same polishing process, there was a difference in surface roughness in all groups. While the highest surface roughness values were seen in 3D-printing, the lowest roughness value was seen in the CAD/CAM milling and was statistically significant (p&amp;lt;0.05). Thermocycling did not show a statistically significant difference in surface roughness (p&amp;gt;0.05).&#x0D; Conclusions: The same polishing process caused different surface roughness values in the denture base materials obtained with different methods, and the lowest surface roughness value was seen in the CAD/CAM milling.

Influence of loading frequency on ULCF life of structural steel under variable surface roughness

AbstractThis paper investigates the effects of a wide range of loading frequencies ranging from 0.005 to 5 Hz and blasting induced surface roughness ranging from 20 to 100 μm on the ultra‐low cycle fatigue (ULCF) life of structural steel. The combined effect of these parameters on ULCF life has not been investigated so far. To this aim, comprehensive ULCF tests were performed on steel specimens under a constant displacement‐controlled environment until the failure occurred. The experimental results manifest that the surface roughness and loading frequency are the governing parameters affecting the ULCF life. The test material exhibits cyclic softening behavior under all loading conditions. An increase in loading frequency from 0.005 to 5 Hz causes a significant increase of 33% and 27% in ULCF life for 20 and 100 μm rough specimens, respectively. However, the effect of frequency on ULCF life becomes less significant at higher values of surface roughness. Moreover, an increase in surface roughness from 20 to 100 μm causes a significant reduction of about 45% and 47% in ULCF life at the loading frequencies of 0.005 and 5Hz, respectively. Furthermore, a correlation between fatigue life and loading frequency as a function of surface roughness is derived by the power law relationship.

Properties of thermally modified Scots pine (Pinus sylvestris L.), Kazdağı fir (Abies equi-trojani Asch. et Sint.), and Eastern beech (Fagus orientalis Lipsky)

Surface roughness and discoloration of thermally modified Scots pine (Pinus sylvestris L.), Kazdağı fir (Abies equi-trojani Asch. et Sint.), and Eastern beech (Fagus orientalis Lipsky) were evaluated. The surface roughness and discoloration of the samples sanded with 60, 80, and 120-grit grades were evaluated at temperature levels of 160, 180, 200, and 220 °C. Findings were subjected to multiple analysis of variance and Duncan’s homogeneity tests; using the SPSS package program, single, double, triple, and quadruple interactions were analyzed. The highest surface roughness values were found in Eastern beech samples with radial cross-section (12.4 µm) finished with 60-grit sandpaper. The lowest roughness value was found in Kazdagi fir samples that were heat-treated in 200 °C and processed with 120-grit sandpaper (2.03 µm). The lowest discoloration evaluation (∆E) value was found eastern beech samples 32.43, and highest ∆E values 46.86 found at Scots pine.

Determination of Surface Roughness of the Land Texture Using Remote Sensing Data and Geo-Informatic Techniques: A Case Study in Kurdistan Region-Iraq

Surface roughness (SR) is a significant geomorphic factor that has been effectively applied to determine material characteristics, present and past processes, and the period passed by since development in the environmental and earth sciences. Thus, this type of study is essential for analyzing SR and its importance. The research efforts to display a coherent evaluation of techniques and remote sensing data. The digital elevation models (DEMs) data were taken into account for quantifying the SR of landscape in different scales in selected areas that belong to the Kurdistan region, north of Iraq. The various types of DEMs {ALOS PALSAR (12.5 m) and SRTM in (30 m) and (90 m) resolution} as remotely sensed data integrated with GIS techniques were used to calculate SR regarding different neighborhood sizes {51 × 51 and 100 × 100 cells moving window size (MWZ)} in the both selected areas. The first study area is a mountainous terrain characterized by a number of anticlines and synclines that are located in High Folded Zones (HFZ), while the second study area is virtually a plain that is located in Low Folded Zones (LFZ). It found that SR calculation in wide and mountainous areas can be efficiently analyzed in more detail by using coarse-resolution DEMs from large MWZ, such as 100 × 100 cells, whereas high-resolution DEMs can be considered for studying SR in small, urban, and plain areas to reach detail information regarding smaller MWZ. The results show that the E and W segments of Safeen and the western segment of Shakrok anticlines have the highest SR values, which indicate high incision at elevated and extremely eroded parts of area one, although Bani Bawi, Pirmam, and Khatibian anticlines have moderate to low SR values due poorly incised. On the other hand, the areas within LFZ are mainly flat and have the lowest values of SR, which indicate a very poorly dissected landscape except for the northwest part of the area two relatively has a higher SR value.

Effect of Current and Pulse-on Time on Material Removal Rate and Surface Roughness of Tungsten Carbide in Electric Discharge Machine Die-sinking

The focus of manufacturing for tungsten carbide applications often demands a smooth surface quality as the result of the Electric Discharge Machine (EDM) die-sinking process, especially in the manufacture of die and mold with tungsten carbide material processed using a die-sinking EDM machine. The purpose of this study is to analyze the effect of electric current and pulse-on time on the Material Removal Rate (MRR) and surface roughness of tungsten carbide. Through the experimental method, the parameters varied, namely electric current 17 A, 20 A, 23 A, and pulse-on time 30 µs, 55 µs, and 80 µs. MRR was calculated through weight loss. Surface roughness was obtained from a surface roughness tester and a Scanning Electron Microscope for surface morphology. The results showed that the highest material removal rate was 1.509 mm3/min at 23 A and 30 µs, and the lowest material removal rate was 0.262 mm3/min at 17 A and 80 µs. The highest surface roughness value was 4.278 µm at 23 A and 80 µs. The lowest surface roughness value was 2.166 µm at 17 A and 30 µs. The tungsten carbide surface topography results are crater, globule, crack, and porous. The greater the current used, the higher the MRR value and surface roughness. Meanwhile, the greater the pulse-on time used, the MRR value decreases, and the surface roughness increases.

Performance evaluation of mixture of groundnut oil and camel milk as cutting fluids on the surface of aluminium during turning

Performance of the mixture of the two extract (groundnut oil and camel milk) as cutting fluid will be evaluated at various proportion and at various speed and feed and on the surface finish of aluminium material as well as the tool life. Various percentage proportions of 80% groundnut oil to 20% camel milk, 60% groundnut oil to 40% camel milk, 40% groundnut oil to 60% camel milk, 20% groundnut oil to 80% camel milk. At each proportion the surface finish as well as tool life will be assessed and evaluated at various speeds and feed during turning on the lathe machine. The anticipated result for this experiment will determine which amount of the mixture proportion gives better surface finish and how much it affects the tool life; the study will also determine the effectiveness of the mixture content as cutting fluid on aluminium material.The Taguchi process optimisation suggested that in mixture ratio higher feedrate affect cutting speed and result to a higher value of surface roughness as the same spindle speed as clearly shows that in the Taghuci analysis response table for mixture of 80% camel milk to 20% groundnut oil. For the rest of the mixture i.e. 60% camel to 40% groundnut oil in the SN Ration Table feedrate tend to go higher at a lower cutting speed as analysed. From the result obtained at spindle speed of 58 rpm and 80%camel milk to 20% groundnut oil feed rate was found to be 34 m,cutting speed was 11600 rpm and surface roughness at 522 µm also at the spindle speed of 850 rpm feedrate was found to be 510 m,cutting speed at 1700 rpm and surface roughness of 1121 µm. At the spindle speed of 1240 rpm feed rate and feed rate was found to be 744 m and cutting speed 24800 rpm and surface roughness found to be 2385 µm respectively.

Reinforcement of resin-modified glass-ionomer cement with glass fiber and graphene oxide

ObjectiveTo evaluate the effect of adding glass fiber and graphene oxide to a resin-modified glass ionomer cement (RMGIC). MethodsExperimental RMGICs were prepared by adding separately and simultaneously glass fibers (5, 10, and 20 wt%) and graphene oxide (1, 3, and 5 wt%) to the powder of RMGIC with different ratios. The samples were examined under SEM and XRD. The surface roughness, flexural strength, Vickers microhardness, water sorption, and solubility were investigated. Data were analyzed using ANOVA and Tukey tests (p = 0.05). ResultsAdding fiber and graphene oxide to RMCIS increased the surface roughness, flexural strength, and microhardness. The highest surface roughness value was obtained in the 20% fiber+5% graphene oxide adding group and the lowest in the control group (p < 0.05). The highest microhardness and flexural strength values were acquired in the 20% fiber-adding group and the lowest in the control group (p < 0.05). 10% and 20% fiber addition increased water sorption and solubility (p < 0.05). Adding 3%, 5% graphene oxide, and 20% fiber+5% graphene oxide reduced water sorption (p < 0.05). The highest water sorption was found in the 20% fiber-adding group and the lowest in the 5% graphene oxide and %20 fiber+5% graphene oxide-adding groups (p < 0.05). Graphene oxide alone and together with fiber did not affect the solubility (p > 0.05). ConclusionThe results show that reinforcement of RMGIC with glass fiber and graphene oxide may improve the mechanical properties. But the glass fibers may cause more water sorption and solubility. Graphene oxide may decrease water sorption of RMGIC and fiber-reinforced RMGIC.

Effect of substrate temperature on the properties of Bi2O3 thin films grown by sol-gel spray coating

Bi2O3 thin films have been successfully deposited on glass substrate by sol-gel spray coating technique at different temperatures between 150 °C and 550 °C using bismuth nitrate pentahydrate as raw material. Thin films were then annealed at a temperature of 350 °C. This study aims to analyze the effect of substrate temperature on the structural, morphological, topological, and optical properties by X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), and UV–Vis Spectroscopy. The diffraction peak position of XRD showed that the as-obtained Bi2O3 thin films were crystalline and different substrate temperatures played a key role in the phase transition β→δ-Bi2O3. The morphology and topology of Bi2O3 show different results which are highly influenced by substrate temperatures whereas Bi2O3 thin film at 450 °C has the highest value of surface roughness. The skewness and kurtosis were also investigated. The optical study showed the band gap energy values of the as-obtained Bi2O3 thin film varied at different substrate temperatures between 2.35 eV and 2.78 eV.

Effect of temperature on anti-corrosion properties of aluminum alloy anodized by sulphuric acid

Temperature is one of the most important parameters in anodizing treatments of aluminum alloys as it directly affects the quality of the anodic coatings. This research study has examined and investigated the effect of this important parameter on the anti-corrosion properties of the anodizing layers of aluminum alloy 5083.The morphology and crystalline structure of anodic oxide layers were characterized respectively by X-ray diffraction, scanning lectron microscopy and EDX analysis. The corrosion behaviour of the alloy, before and after anodization at different temperatures, was analyzed in chlorinated medium using different electrochemical techniques, namely open circuit potential measurement, potentiodynamic polarization and electrochemical impedance spectroscopy. The results showed that temperature has a significant influence on the quality of the anodic oxide layers. Therefore, for a relatively low treatment temperature, the developed anodic films show high surface roughness values and contain fewer pores and defects compared to the films obtained at 20°C. Electrochemical analysis indicates that these films also show good corrosion resistance in the chloride environment. This is reflected by relatively low corrosion current density values as well as relatively high polarization resistance values.