Cellulose is a fascinating biopolymer and sustainable raw material. Cellulose particles with at least one dimension in the nanoscale are referred to as nanocellulose. Kenaf fiber is a natural fiber used in this study because it has high mechanical properties and strong interface adhesion with polymers so it provides superior properties to other natural fibers. Polyurethane (PU) foam is widely used as a core layer in sandwich composite construction to produce a lightweight material. This study presents a synthesis of cellulose nano-fibrils (CNF) extracted from East Java, Indonesia based kenaf fibers, an analysis of the effect of adding CNF as a filler and a reinforcement in PU foam composites, and a formulation of PU-CNF foam composite that provided the best mechanical properties as strong and lightweight materials in structural applications. The CNF extraction from kenaf fiber started by fiber pre-treatment including alkalization and bleaching, then mechanical treatment with an Ultra Fine Grinder to produce CNF suspension. The weight variations of CNF in PU foam were 0, 3, 5, 7, and 10 wt%. PU-CNF composite fabrication using the in-situ polymerization method. CNF characterization included TEM, XRD, and FT-IR. TEM results on CNF show that the CNF diameter is in the range of 40-70 nm. The functional group from the FT-IR results showed that the pre-treatment process on kenaf fiber was successful in reducing the lignin and hemicellulose content. XRD results showed that the CNF crystallinity was 75.22%. The PU-CNF foam composite characterization included a compressive test, 3-point bending test, and SEM. The PU foam composite with 3 wt% CNF reinforcement is the best composite which has the optimum value from the results of the compression test and the 3-point bending test. The compressive strength value increased by 20.01%, from 236.997 kPa to 284.434 kPa, the compressive modulus value increased by 29.21% from 5.67 MPa to 7.32 MPa, and the 3-point bending strength value increased 28.29% from 572.24 to 734.15 kPa. All the results expected to support that CNF was a potential reinforcement material with a high surface area for a wide variety of applications.
{"title":"Synthesis and Effect of Nanocellulose Obtained from East Java Kenaf Fiber on Mechanical Properties of Polyurethane Foam Composites as Strong and Lightweight Materials","authors":"Yunella Amelia Siagian, A. Juwono, S. Roseno","doi":"10.4028/p-t28t39","DOIUrl":"https://doi.org/10.4028/p-t28t39","url":null,"abstract":"Cellulose is a fascinating biopolymer and sustainable raw material. Cellulose particles with at least one dimension in the nanoscale are referred to as nanocellulose. Kenaf fiber is a natural fiber used in this study because it has high mechanical properties and strong interface adhesion with polymers so it provides superior properties to other natural fibers. Polyurethane (PU) foam is widely used as a core layer in sandwich composite construction to produce a lightweight material. This study presents a synthesis of cellulose nano-fibrils (CNF) extracted from East Java, Indonesia based kenaf fibers, an analysis of the effect of adding CNF as a filler and a reinforcement in PU foam composites, and a formulation of PU-CNF foam composite that provided the best mechanical properties as strong and lightweight materials in structural applications. The CNF extraction from kenaf fiber started by fiber pre-treatment including alkalization and bleaching, then mechanical treatment with an Ultra Fine Grinder to produce CNF suspension. The weight variations of CNF in PU foam were 0, 3, 5, 7, and 10 wt%. PU-CNF composite fabrication using the in-situ polymerization method. CNF characterization included TEM, XRD, and FT-IR. TEM results on CNF show that the CNF diameter is in the range of 40-70 nm. The functional group from the FT-IR results showed that the pre-treatment process on kenaf fiber was successful in reducing the lignin and hemicellulose content. XRD results showed that the CNF crystallinity was 75.22%. The PU-CNF foam composite characterization included a compressive test, 3-point bending test, and SEM. The PU foam composite with 3 wt% CNF reinforcement is the best composite which has the optimum value from the results of the compression test and the 3-point bending test. The compressive strength value increased by 20.01%, from 236.997 kPa to 284.434 kPa, the compressive modulus value increased by 29.21% from 5.67 MPa to 7.32 MPa, and the 3-point bending strength value increased 28.29% from 572.24 to 734.15 kPa. All the results expected to support that CNF was a potential reinforcement material with a high surface area for a wide variety of applications.","PeriodicalId":18861,"journal":{"name":"Nano Hybrids and Composites","volume":"67 1","pages":"79 - 90"},"PeriodicalIF":0.4,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83853366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Spinel ferrites nanoparticles have attracted the attention of researcher for memory storage devices. We have synthesized MgFeO4 pure sample and MgFe1.8Sm0.2O4 doped sample via solgel technique. The study of structural, electrical, dielectric, and I-V properties were studied of synthesized spinel magnesium ferrites nanoparticles. X-ray diffraction (XRD) confirmed the spinel structure of both compositions. The frequency dependent AC conductivity, dielectric constant, dielectric tangent loss, was studied in the range of 20Hz to 3MHz. I-V measurements has been done for the resistive switching properties. I-V curves of both compositions in the current study exhibits the formation of hysteresis loop. The hysteresis loop behavior shows that with the addition of samarium the trend of loop increases which plays crucial role as a Resistive Random-Access Memory (ReRAM) application in switching memory storage devices.
{"title":"Structural and Electrical Properties of Pure and Samarium Doped MgFe2O4 Nanoparticles for Resistive RAM Applications","authors":"Haroon Mazhar, M. Anis-Ur-Rehman","doi":"10.4028/p-0p3dbj","DOIUrl":"https://doi.org/10.4028/p-0p3dbj","url":null,"abstract":"Spinel ferrites nanoparticles have attracted the attention of researcher for memory storage devices. We have synthesized MgFeO4 pure sample and MgFe1.8Sm0.2O4 doped sample via solgel technique. The study of structural, electrical, dielectric, and I-V properties were studied of synthesized spinel magnesium ferrites nanoparticles. X-ray diffraction (XRD) confirmed the spinel structure of both compositions. The frequency dependent AC conductivity, dielectric constant, dielectric tangent loss, was studied in the range of 20Hz to 3MHz. I-V measurements has been done for the resistive switching properties. I-V curves of both compositions in the current study exhibits the formation of hysteresis loop. The hysteresis loop behavior shows that with the addition of samarium the trend of loop increases which plays crucial role as a Resistive Random-Access Memory (ReRAM) application in switching memory storage devices.","PeriodicalId":18861,"journal":{"name":"Nano Hybrids and Composites","volume":"37 1","pages":"1 - 7"},"PeriodicalIF":0.4,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73466648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AuNPs have been synthesized with reducing agents and sodium citrate covering agents using the colorimetric method. The formation of sodium citrate-covered AuNPs was confirmed using a UV-Vis spectrophotometer. The optimization of creatinine concentration of 10 mM was indicated by shifting the absorption peak from 530 to 700 nm. The results of this optimization were then used to standardize the detection of creatinine in urine samples using a validation test method. The TEM results showed that the AuNPs were dispersed at relatively large distances. The size of the AuNPs was 30.67 nm and creatinine was 19.96 nm. This is because no substance had aggregate NPS, therefore, the particles are still scattered. Testing the quantitative value of Red-Green-Blue (RGB) digital images involved a mobile phone camera. The resulting images were stored in a memory card and then transferred to a laptop/computer. The data were processed using ImageJ software. The linear correlation and selectivity of the quantitative values of Red-Green-Blue (RGB) from the RGB method were compared with the results of colorimetric detection using the UV-Vis spectrophotometric method. The data were used to determine the amount of creatinine concentration. The results exhibited that sodium citrate had the ability as a reducing agent and a covering agent in the synthesis of AuNPs for the determination of creatinine. The RGB digital image method had good sensitivity to creatinine with LoD of 0.068 mM dan LoQ of 0.228 mM, which was smaller than the UV-Vis spectrophotometric method where LoD was 0.225 mM and LoQ was 0.751 mM. The validation method results showed that AuNPs can be used as a creatinine sensor. This method used a colorimetric sensor of the Red-Green-Blue (RGB) component in urine samples and was translated with ImageJ software.
采用比色法，用还原剂和柠檬酸钠覆盖剂合成了AuNPs。用紫外可见分光光度计证实了柠檬酸钠覆盖AuNPs的形成。通过将吸收峰从530 nm移至700 nm，确定了10 mM时肌酸酐浓度的最佳选择。该优化结果将用于标准化尿液中肌酐的检测，并采用验证试验方法。TEM结果表明，AuNPs在较远距离上分散。aunp大小为30.67 nm，肌酐大小为19.96 nm。这是因为没有物质具有聚集的NPS，因此，颗粒仍然是分散的。测试红绿蓝(RGB)数字图像的定量值涉及手机相机。生成的图像存储在存储卡中，然后传输到笔记本电脑/计算机。使用ImageJ软件对数据进行处理。比较了RGB法测定红绿蓝(RGB)定量值与紫外可见分光光度法测定结果的线性相关性和选择性。该数据用于测定肌酐浓度。结果表明，柠檬酸钠在测定肌酐的AuNPs合成中具有还原剂和覆盖剂的作用。RGB数字图像法对肌酐的灵敏度较好，LoD为0.068 mM, LoQ为0.228 mM，小于UV-Vis分光光度法的LoD为0.225 mM, LoQ为0.751 mM。验证方法结果表明，AuNPs可以作为肌酐传感器。该方法使用尿液样本中的红绿蓝(RGB)成分比色传感器，并使用ImageJ软件进行翻译。
{"title":"Synthesis of Sodium Citrate-Capped Gold Nanoparticles and its Application for Creatinine Detection in Urine Sample by Colorimetric Analysis Based on the Red-Green-Blue (RGB) Digital Image","authors":"Heppy Findari, Mudasir, S. J. Santosa","doi":"10.4028/p-5k654i","DOIUrl":"https://doi.org/10.4028/p-5k654i","url":null,"abstract":"AuNPs have been synthesized with reducing agents and sodium citrate covering agents using the colorimetric method. The formation of sodium citrate-covered AuNPs was confirmed using a UV-Vis spectrophotometer. The optimization of creatinine concentration of 10 mM was indicated by shifting the absorption peak from 530 to 700 nm. The results of this optimization were then used to standardize the detection of creatinine in urine samples using a validation test method. The TEM results showed that the AuNPs were dispersed at relatively large distances. The size of the AuNPs was 30.67 nm and creatinine was 19.96 nm. This is because no substance had aggregate NPS, therefore, the particles are still scattered. Testing the quantitative value of Red-Green-Blue (RGB) digital images involved a mobile phone camera. The resulting images were stored in a memory card and then transferred to a laptop/computer. The data were processed using ImageJ software. The linear correlation and selectivity of the quantitative values of Red-Green-Blue (RGB) from the RGB method were compared with the results of colorimetric detection using the UV-Vis spectrophotometric method. The data were used to determine the amount of creatinine concentration. The results exhibited that sodium citrate had the ability as a reducing agent and a covering agent in the synthesis of AuNPs for the determination of creatinine. The RGB digital image method had good sensitivity to creatinine with LoD of 0.068 mM dan LoQ of 0.228 mM, which was smaller than the UV-Vis spectrophotometric method where LoD was 0.225 mM and LoQ was 0.751 mM. The validation method results showed that AuNPs can be used as a creatinine sensor. This method used a colorimetric sensor of the Red-Green-Blue (RGB) component in urine samples and was translated with ImageJ software.","PeriodicalId":18861,"journal":{"name":"Nano Hybrids and Composites","volume":"53 1","pages":"23 - 31"},"PeriodicalIF":0.4,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77284905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alexandru Adrian Geană, N. Sîrbu, Matei Marin-Corciu, I. Duma
This paper will present the mechanical capacity of 3D printed test specimens, in direct correlation with their infill pattern, that were made from polyamide (also called nylon) reinforced with carbon fibers (in proportion of 20%). Nylon is a flexible, but strong material, and carbon fibers give it increased mechanical strength, which will be shown by the mechanical test’s results. The infill’s density is 50%, which gives enough strength for most prototyping applications and reduces the print time considerably. The geometries of infill tested in this paper are lines, honeycomb and gyroid. Preliminary results showed that the higher the printing temperature, the better the layers weld and bond, thus the mechanical properties increase.
{"title":"Establishing the Optimal Infill for Peak Tensile and Compressive Performance of CF Reinforced Polyamide Test Specimens Manufactured through Additive Manufacturing","authors":"Alexandru Adrian Geană, N. Sîrbu, Matei Marin-Corciu, I. Duma","doi":"10.4028/p-l16l2d","DOIUrl":"https://doi.org/10.4028/p-l16l2d","url":null,"abstract":"This paper will present the mechanical capacity of 3D printed test specimens, in direct correlation with their infill pattern, that were made from polyamide (also called nylon) reinforced with carbon fibers (in proportion of 20%). Nylon is a flexible, but strong material, and carbon fibers give it increased mechanical strength, which will be shown by the mechanical test’s results. The infill’s density is 50%, which gives enough strength for most prototyping applications and reduces the print time considerably. The geometries of infill tested in this paper are lines, honeycomb and gyroid. Preliminary results showed that the higher the printing temperature, the better the layers weld and bond, thus the mechanical properties increase.","PeriodicalId":18861,"journal":{"name":"Nano Hybrids and Composites","volume":"1 1","pages":"113 - 123"},"PeriodicalIF":0.4,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73175208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Barnasas, N. Diamantopoulos, D. I. Anyfantis, N. Bouropoulos, Politis Constantin, P. Poulopoulos
Thin Mo films in the thickness range between 1 and 164 nm have been deposited on high-quality quartz and Corning glass substrates by Radio Frequency (RF) magnetron sputtering under high vacuum (base pressure ~ 3 × 10-7 mbar). The sputtering target was metallic Mo. Subsequent short annealing of Mo at temperatures between about 400 °C - 600 °C in a muffle furnace in air produced MoO3 thin films. Heating even to 400°C resulted in significant growth of crystal size. Surprisingly, films thinner than about 50 nm could not be heated at higher temperatures due to the evaporation of the oxide. Ultraviolet – visible light absorption spectroscopy experiments were employed for the determination of the optical band gap. The results for direct and indirect allowed transitions are discussed.
{"title":"Growth and Optical Properties of MoO3 thin Films","authors":"A. Barnasas, N. Diamantopoulos, D. I. Anyfantis, N. Bouropoulos, Politis Constantin, P. Poulopoulos","doi":"10.4028/p-2su8d8","DOIUrl":"https://doi.org/10.4028/p-2su8d8","url":null,"abstract":"Thin Mo films in the thickness range between 1 and 164 nm have been deposited on high-quality quartz and Corning glass substrates by Radio Frequency (RF) magnetron sputtering under high vacuum (base pressure ~ 3 × 10-7 mbar). The sputtering target was metallic Mo. Subsequent short annealing of Mo at temperatures between about 400 °C - 600 °C in a muffle furnace in air produced MoO3 thin films. Heating even to 400°C resulted in significant growth of crystal size. Surprisingly, films thinner than about 50 nm could not be heated at higher temperatures due to the evaporation of the oxide. Ultraviolet – visible light absorption spectroscopy experiments were employed for the determination of the optical band gap. The results for direct and indirect allowed transitions are discussed.","PeriodicalId":18861,"journal":{"name":"Nano Hybrids and Composites","volume":"101 1","pages":"1 - 12"},"PeriodicalIF":0.4,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82405217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ZnO nanorods and ZnO nanowires were obtained using solutions of zinc chloride and zinc acetate dihydrate, respectively, as precursors. The thin films were deposited by ultrasonic spray pyrolysis onto glass substrates at 350 °C and their morphological, structural, and optical properties were investigated. ZnO nanostructures morphologies were observed by SEM and images showed that a large amount of ZnO nanorods and nanowires were deposited onto the full substrates surfaces. The films have polycrystalline nature and hexagonal wurtzite structure with (002) and (101) preferential orientations for ZnO nanorods and nanowires, respectively. The crystallite size was found to be in the range of 30 nm. The films exhibit an optical transparency in the visible region of about 60 % for ZnO nanowires and 30 % for ZnO nanorods. The different ZnO films were used as photocatalysts to study the photodegradation of methyl green dye induced by UV light. ZnO nanorods exhibited higher photodegradation efficiency and a larger rate constant than ZnO nanowires leading to an improvement from 60 % to 80 % of the degradability of the dye.
{"title":"UV-Induced Photocatalytic Degradation of Methyl Green Dye by ZnO Nanowires and Nanorods Obtained by Spray Pyrolysis","authors":"Loubna Hafsa, L. Hadjeris, L. Herissi","doi":"10.4028/p-663328","DOIUrl":"https://doi.org/10.4028/p-663328","url":null,"abstract":"ZnO nanorods and ZnO nanowires were obtained using solutions of zinc chloride and zinc acetate dihydrate, respectively, as precursors. The thin films were deposited by ultrasonic spray pyrolysis onto glass substrates at 350 °C and their morphological, structural, and optical properties were investigated. ZnO nanostructures morphologies were observed by SEM and images showed that a large amount of ZnO nanorods and nanowires were deposited onto the full substrates surfaces. The films have polycrystalline nature and hexagonal wurtzite structure with (002) and (101) preferential orientations for ZnO nanorods and nanowires, respectively. The crystallite size was found to be in the range of 30 nm. The films exhibit an optical transparency in the visible region of about 60 % for ZnO nanowires and 30 % for ZnO nanorods. The different ZnO films were used as photocatalysts to study the photodegradation of methyl green dye induced by UV light. ZnO nanorods exhibited higher photodegradation efficiency and a larger rate constant than ZnO nanowires leading to an improvement from 60 % to 80 % of the degradability of the dye.","PeriodicalId":18861,"journal":{"name":"Nano Hybrids and Composites","volume":"519 1","pages":"69 - 80"},"PeriodicalIF":0.4,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77683000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fused Deposition Modeling (FDM) is generally used to fabricate complex geometry structures and it has found applicability in various industries, such as the biomedical, aerospace, automotive, and building industries. As the mechanical properties and tribological behaviour of the 3D printing components are critical during operation, it is necessary to study the influence of process parameters and chemical composition on these specific characteristics. The paper aims to determine the coefficient of friction and wear behaviour of three different 3D-printed polylactic acid (PLA) materials in contact with a metallic counterbody. 3D printing process of the proposed PLA filaments was achieved by applying the FDM technique, using same deposition parameters for all three types of materials. Tribological characteristics of the 3D printed polymers were evaluated using pin-on-disk method and a comparison among the obtained frictional features of the specimens has been analyzed. The printed PLA samples show significant differences in sliding wear behaviour, the material loss of Co-reinforced PLA specimen is much more substantial than that obtained for PLA and tough PLA samples, due to the presence of metallic particles, hence for this specimen, an inferior wear resistance is attributed.
{"title":"Tribological Properties of Different 3D Printed PLA Filaments","authors":"R. Muntean, Sebastian Ambruș, N. Sîrbu, I. Uțu","doi":"10.4028/p-8k2v92","DOIUrl":"https://doi.org/10.4028/p-8k2v92","url":null,"abstract":"Fused Deposition Modeling (FDM) is generally used to fabricate complex geometry structures and it has found applicability in various industries, such as the biomedical, aerospace, automotive, and building industries. As the mechanical properties and tribological behaviour of the 3D printing components are critical during operation, it is necessary to study the influence of process parameters and chemical composition on these specific characteristics. The paper aims to determine the coefficient of friction and wear behaviour of three different 3D-printed polylactic acid (PLA) materials in contact with a metallic counterbody. 3D printing process of the proposed PLA filaments was achieved by applying the FDM technique, using same deposition parameters for all three types of materials. Tribological characteristics of the 3D printed polymers were evaluated using pin-on-disk method and a comparison among the obtained frictional features of the specimens has been analyzed. The printed PLA samples show significant differences in sliding wear behaviour, the material loss of Co-reinforced PLA specimen is much more substantial than that obtained for PLA and tough PLA samples, due to the presence of metallic particles, hence for this specimen, an inferior wear resistance is attributed.","PeriodicalId":18861,"journal":{"name":"Nano Hybrids and Composites","volume":"8 1","pages":"103 - 111"},"PeriodicalIF":0.4,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87451711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. E. Ibrahim, M. abed el-Raouf, Nourhan A. Mohamed
Recently, addition of nanofillers to insulating fluids to increase its breakdown voltage finds a great interest from researchers. Understanding the reasons of the increased breakdown voltage with addition of nanofillers at certain loadings to insulating fluids is of great importance. Hence, understanding how electric breakdown occurs in nanofluids can help researchers to select the more suitable nanofiller material, nanofiller particle size ....... etc. to be added to insulating fluids. Therefore, in this paper, a generalized electric breakdown mechanism of insulating nanofluids is presented. The generalized mechanism takes different parameters into consideration. These parameters are nanoparticle permittivity, nanoparticle size and insulating fluid temperature. To demonstrate the validity of the generalized breakdown mechanism, theoretical computations are carried out using finite element analysis. Also, breakdown experiments considering transformer oil are carried out considering different nanofiller materials, nanofiller sizes at different temperatures.
{"title":"Towards a Generalized Electric Breakdown Mechanism of Insulating Nanofluids","authors":"M. E. Ibrahim, M. abed el-Raouf, Nourhan A. Mohamed","doi":"10.4028/p-jj4qou","DOIUrl":"https://doi.org/10.4028/p-jj4qou","url":null,"abstract":"Recently, addition of nanofillers to insulating fluids to increase its breakdown voltage finds a great interest from researchers. Understanding the reasons of the increased breakdown voltage with addition of nanofillers at certain loadings to insulating fluids is of great importance. Hence, understanding how electric breakdown occurs in nanofluids can help researchers to select the more suitable nanofiller material, nanofiller particle size ....... etc. to be added to insulating fluids. Therefore, in this paper, a generalized electric breakdown mechanism of insulating nanofluids is presented. The generalized mechanism takes different parameters into consideration. These parameters are nanoparticle permittivity, nanoparticle size and insulating fluid temperature. To demonstrate the validity of the generalized breakdown mechanism, theoretical computations are carried out using finite element analysis. Also, breakdown experiments considering transformer oil are carried out considering different nanofiller materials, nanofiller sizes at different temperatures.","PeriodicalId":18861,"journal":{"name":"Nano Hybrids and Composites","volume":"113 1","pages":"81 - 88"},"PeriodicalIF":0.4,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89389356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The goal of this study is to improve the accuracy and the validity of the prediction of the heat transfer coefficient (HTC) throughout flow boiling of different water-based nanofluids in a horizontal tube by developing an artificial neural network model using Ag/water, Cu/water, CuO/water, Al2O3/water, and TiO2/water nanofluids. The multiple layer perceptron (MLP) neural network was designed and trained by 354 experimental data points that were collected from the literature. Thermal conductivity of nanoparticle, mass flux, volumetric concentration, and heat flux were used to serve as input variables of the model. The heat transfer coefficient (HTC) was used as the output variable. Via the method of the trial-and error, MLP with 8 neurons in the hidden layer was attained as the optimal artificial neural network structure. This developed smart model is more accordant with the experimental data than the correlations of the literature. The accuracy of the developed smart model was validated by the value of mean squared error (MSE=0.042) and the value of determination coefficient (R2= 0.9992 ) for all data.
{"title":"A Smart Model for the Prediction of Heat Transfer Coefficient during Flow Boiling of Nanofluids in Horizontal Tube","authors":"Adel Bouali, B. Mohammedi, S. Hanini","doi":"10.4028/p-9ge01g","DOIUrl":"https://doi.org/10.4028/p-9ge01g","url":null,"abstract":"The goal of this study is to improve the accuracy and the validity of the prediction of the heat transfer coefficient (HTC) throughout flow boiling of different water-based nanofluids in a horizontal tube by developing an artificial neural network model using Ag/water, Cu/water, CuO/water, Al2O3/water, and TiO2/water nanofluids. The multiple layer perceptron (MLP) neural network was designed and trained by 354 experimental data points that were collected from the literature. Thermal conductivity of nanoparticle, mass flux, volumetric concentration, and heat flux were used to serve as input variables of the model. The heat transfer coefficient (HTC) was used as the output variable. Via the method of the trial-and error, MLP with 8 neurons in the hidden layer was attained as the optimal artificial neural network structure. This developed smart model is more accordant with the experimental data than the correlations of the literature. The accuracy of the developed smart model was validated by the value of mean squared error (MSE=0.042) and the value of determination coefficient (R2= 0.9992 ) for all data.","PeriodicalId":18861,"journal":{"name":"Nano Hybrids and Composites","volume":"17 1","pages":"89 - 102"},"PeriodicalIF":0.4,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79127881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Greener Nanotechnology research depends on the utilization of the reductive potency of a common byproduct of food and fruit processing industry which represent a cheap and reliable source of green reducing agents to be used in bio-nanosynthesis. One potential approach is based on silver bio-synthesis (AgNPs) using biological waste products. Recently, the production of bio-nanoparticles especially AgNPs has received enormous importance due to its good and potential physicochemical characteristics and the possibility of applications .The present work aimed to synthesis silver nanoparticles (AgNPs) using biological orange waste peels products (Citrus Sinensis) to evaluate its characterization, antimicrobial activity and cytotoxicity. The green synthesized silver nanoparticles were characterized by UV-visible spectroscopy and Scanning electron microscopy (SEM). Disk diffusion method was used for the study of antimicrobial activity of the bio-synthesized silver nanoparticles against the different bacterial and fungal strains. Characterization performed by Scanning Electron Microscope and UV visible spectrophotometer where showed the formation of spherical, and few agglomerated AgNPs forms as measured by UV–visible spectrophotometer in the range of 350-550 nm. Antimicrobial activities where showed positive activity against most of the tested human pathogenic bacteria and fungi with varying degrees and the cytotoxicity which performed against African Green Monkey Kidney cell lines (Vero) where CC50 for AgNO3 and AgNPs were ( 76.5±6.27 μl/100μl ) and (9.87±0.90μl/100μl) respectively.
{"title":"Eco-Friendly Green Biosynthesis of Silver Nanoparticles (Or-AgNPs) Using Orange Peel (Citrus sinensis) Waste and Evaluation of their Antibacterial and Cytotoxic Activities","authors":"S. A. Mohamed","doi":"10.4028/p-9pjwgi","DOIUrl":"https://doi.org/10.4028/p-9pjwgi","url":null,"abstract":"Greener Nanotechnology research depends on the utilization of the reductive potency of a common byproduct of food and fruit processing industry which represent a cheap and reliable source of green reducing agents to be used in bio-nanosynthesis. One potential approach is based on silver bio-synthesis (AgNPs) using biological waste products. Recently, the production of bio-nanoparticles especially AgNPs has received enormous importance due to its good and potential physicochemical characteristics and the possibility of applications .The present work aimed to synthesis silver nanoparticles (AgNPs) using biological orange waste peels products (Citrus Sinensis) to evaluate its characterization, antimicrobial activity and cytotoxicity. The green synthesized silver nanoparticles were characterized by UV-visible spectroscopy and Scanning electron microscopy (SEM). Disk diffusion method was used for the study of antimicrobial activity of the bio-synthesized silver nanoparticles against the different bacterial and fungal strains. Characterization performed by Scanning Electron Microscope and UV visible spectrophotometer where showed the formation of spherical, and few agglomerated AgNPs forms as measured by UV–visible spectrophotometer in the range of 350-550 nm. Antimicrobial activities where showed positive activity against most of the tested human pathogenic bacteria and fungi with varying degrees and the cytotoxicity which performed against African Green Monkey Kidney cell lines (Vero) where CC50 for AgNO3 and AgNPs were ( 76.5±6.27 μl/100μl ) and (9.87±0.90μl/100μl) respectively.","PeriodicalId":18861,"journal":{"name":"Nano Hybrids and Composites","volume":"36 1","pages":"57 - 68"},"PeriodicalIF":0.4,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77834386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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