bluuebunny/crossref_metadata_2025_split huggingface dataset:
AE signature analysis using continuous and discrete wavelet transforms to predict grinding wheel conditions
Authors: Shivith K , Rameshkumar K 
Published: February 2021

Abstract
In this study, experiments were conducted in a surface grinding operation to acquire and analyze the AE signature to establish a statistical correlation between Acoustic Emission features extracted in wavelet domain with grinding wheel conditions. Grinding wear plot was established to identify the grinding wheel conditions by monitoring the wear in the abrasive grinding wheel and workpiece. Continuous and Discrete Wavelet transforms were carried out to extract the wavelet coefficients. Decision Tree based statistical models were built using discrete and continuous wavelet coefficients. The performance of J48 Decision tree and Classification and Regression Decision Tree (CART) are compared using the classification accuracy and kappa statistics measures. In discrete wavelet transforms, wavelet coefficients are extracted using four mother wavelets namely Haar, Daubechies, Symlet, and Coiflet. In Continuous Wavelet Transforms, the Morlet wavelet is used to extract the 1D wavelet coefficients using 2D scalograms.
Extraction of microbial chitosan for piezoelectric application
Authors: Zamli M I , Ahmad F B , Akmal M H M 
Published: February 2021

Abstract
Chitosan is a natural polysaccharide derived from chitin which is found in the fungus cell walls and crustacean shells. Chitosan has generated a great interest in piezoelectric application because of its interesting properties such as biodegradability, biocompatibility, and low toxicity. The purpose of this study is to focus on the cultivation, fabrication and characterization of chitosan thin film from fungal strain, Aspergillus oryzae cell walls. The fungi was cultivated in bioreactor. Fabrication of chitosan thin film via solvent casting method was optimized via one-factor-at-a-time (OFAT) with 2 parameters (drop-casting volume of solution and drying temperature). Pure chitosan dissolved in formic acid at 0.25 M concentration, dried at 60°C with 35 mL of solution volume gave the highest mechanical quality factor (3.22) and the lowest dissipation factor (0.327) for thin film fabrication. The optimized fabricate thin film was validated using fungal chitosan and shows the results of mechanical quality factor (3.68) and dissipation factor (0.248) which is comparable to conventional piezopolymer thin film. Therefore, fungal chitosan thin film obtained in this study has the potential to be used in piezoelectric application.
Design and Implementation of FEC for CDMA System
Authors: Smrithi M N , Abdul Rajak A R 
Published: February 2021

Abstract
In every wireless communication the data that is transferred is at a high risk of falling under the clutches of various types of disturbances termed as noise, there are various types of noises which are thermal noise, shot noise, IF noise, burst noise, avalanche noise etc. they occur due to a number of factors it can be due to temperature, device malfunctioning and frequency interference. Due to this, the data being transferred in the wireless communication channel gets corrupted resulting in data loss. This problem is rectified by employing FEC (Forward Error Correction) method on the data being transferred. This research focuses on the implementation of various FEC codes in CDMA system to study its detailed performance analysis with the help of MATLAB Software.
Investigative analysis of match-line sensing schemes in TCAM for high-speed performance
Authors: Faisal Fahim , Nishat Mirza Muntasir , Mim Sayka Afreen , Akter Hafsa , Kaysar Shagor Md. Rafid 
Published: February 2021

Abstract
This paper delineates an investigation of TCAM-design techniques for both circuit level and architectural level. In the case of circuit level, low power Match Line sensing techniques and Search Line driving propositions are exhibited. At the architectural level, four processes for curtailing power absorption are introduced. In this paper, 16×16 bit TCAM is designed in 0.18μm CMOS. The hypothesized Match Line sensing scheme truncates power absorption by pruning search time and dampering voltage swing of traditional ones. With respect to the conventional CR-MLSA, the proposed MLSAs delineate the depletion of 56% and 48% for measuring energy. For simulation, 1.8V supply voltage is used.
Ultracompact gas-sensor based on a 2D photonic crystal waveguide incorporating with tapered microcavity
Authors: Harhouz A , Hocini A , Tayoub H 
Published: February 2021

Abstract
In this study, a new ultra compact gas-sensor, based on a 2D photonic crystal waveguide incorporating with tapered microcavity, is designed to detect small refractive index changes. The refractive index (RI) sensor is formed by a point-defect resonant cavity in the sandwiched waveguide on Si slab with triangular lattice. The properties of the sensor are simulated by using the plane wave expansion (PWE) method and the finite-difference time-domain (FDTD) algorithm. The transmission spectra of the sensor with different ambient refractive indices ranging from n = 1.0 to n = 1.01 are calculated. The calculation results show that a change in ambient refractive index of Δn=1×10−4is apparent. The proposed sensor achieves a sensitivity (Δλ/Δn) of 523.2 nm/RIU. It was found that the resonance wavelength is a linear function of the refractive index in under study range. The sensor is appropriate for detecting homogeneous media.
Impact of using nano-hydroxyapatite on postoperative hypersensitivity of two bleaching techniques – randomized controlled clinical trial
Authors: Mohamed H , Fayed A , Elkassas D , Hassanien O 
Published: February 2021

AbstractTo evaluate the impact of using Nano-hydroxyapatite on post-bleaching hypersensitivity after using two different bleaching techniques. Twenty-eight patients were enrolled in this study according to inclusion and exclusion criteria. The patients were randomly assigned into four groups (n=7). G1; bleaching was performed using photo-catalyzed bleaching technique (Philips, zoom), followed by application of Amorphous Calcium phosphate based desensitizing agent (ACP, Relief ACP). G2; bleaching was performed using chemo-catalyzed bleaching technique (Philips, Dash), followed by application of ACP. G3: bleaching was performed using zoom, followed by application of nano-hydroxyapatite based desensitizing agent (Nano p), G4: bleaching was performed using Dash, followed by application of Nano-hydroxyapatite. Post bleaching hypersensitivity was assessed using “Visual analogue scale”. Hypersensitivity was evaluated after: bleaching immediately, application of the desensitizing agent immediately, 24 hours, 48 hours and after one week. Cases with severe hypersensitivity were relieved immediately after Nano p application, meanwhile in case of ACP, cases with severe pain were relieved after 24 hours after its application. Statistically significant difference was evident with the photo catalyzed group immediately after Nano p application than before its application. Reduction in hypersensitivity by time was evident in both the chemo and photo catalyzed groups. In addition, it was found that after one week, all pain scores disappeared with all tested groups. Nano hydroxyapatite particles have an immediate (just post application) relief effect of severe pain with both used bleaching systems. However, the post bleaching hypersensitivity diminished completely after 1 week, irrespective of the desensitizing agent used. The application of Nano hydroxyapatite paste after bleaching is a valid method for diminishing severe post bleaching hypersensitivity when applied with either a photo or chemo catalyzed bleaching agents.
Synthesis, spectroscopic study, biological activity and dyeing application of curcumin - Schiff base with various metal ions complexes
Authors: Ali A M , Al-Noor T H 
Published: February 2021

Abstract
A tetradentate (N2O2) Schiff base (H2Ldfm) was successfully synthesized via condensation of curcumin / diferuloylmethane (dfm) and L-leucine amino acid (HL). There were three different methods that used for synthesizing H2Ldfm; (refluxing, grading, and fusion). Ten different metal complexes were also successfully synthesized by combination of the Schiff base (H2Ldfm) and 1,10-phenanthroline (phen) ligand to form a hexadentate (N4O2) mixed ligands (Ldfm, phen) with ten different metal salts (M) where{ M= Al(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Ag(I), Cd(II), Hg(II), and Pb(II)}. The molar ratio of reactants was (1:1:1) (M: H2Ldfm : phen). The new Schiff base and its new complexes were characterized by different physicochemical techniques such as FT-IR, UV-Visible, elemental analysis (C.H.N), 13C-NMR, 1H-NMR, molar conductivity, mass spectroscopy, magnetic susceptibility, and thermal analysis. All complexes exhibited octahedral geometry. The solution conductivity of (Al (III), Fe (III), and Ag(I)) complexes in DMSO shows an electrolytic behavior, while the solution conductivity of (Mn(II), Co(II), Ni(II), Cu(II), Cd(II), Hg(II) and Pb(II)) complexes shows non-electrolytic attitude. The Schiff base (H2Ldfm) and its metal complexes were used for industrial and biological application such as dyeing cotton fibers testing and two types of bacteria testing like (Staphylococcus aureus and Escherichia Coli).
Dielectric and dynamic mechanical properties of Rochelle salt / PVA composites
Authors: Taha E O , Nasr G M 
Published: February 2021

Abstract
A new type of PVA composites containing Rochelle salt was prepared using the casting method. The electrical, Dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) tests were performed on 0, 20, 30, and 50 weight% PVA based Rochelle salt to identify the effect of salt on the electrical, thermal and mechanical properties of composites. The results showed that the dielectric properties of composites were greatly improved by the addition of salt. The dielectric constant by 28.5%, 98.4% and 236.5% for composite contents 20 wt%, 30 wt% and 50 wt% Rochelle salt, respectively. The observations of dynamic mechanical analysis indicated that the adding of salt reduces both the storage modulus and affect the glass transition temperature of the composites. Moreover, the thermal stability and char yield of the PVA composites were highly affected by the Rochelle salt content.
Shear bond strength of bio-active cement versus self-adhesive resin cement with enamel and dentin when bonded to zirconia in wet and dry conditions (in-vitro study)
Authors: Elattar M A , Khalil A H , Younis J F 
Published: February 2021

Abstract
ACTIVA bio-active cement is resin-modified glass-ionomer cement that was introduced for re-mineralizing of the disintegrated joint. Due to the lack of data about this bioactive cement, this study evaluated the shear bond strength of bioactive cement and self-adhesive resin cements to tooth substrate (enamel and dentin), in wet and dry conditions when bonded to zirconia. In this study, 40 extracted mandibular molars caries-free were collected. Each tooth was cut by diamond disk (bucco-lingual section) to expose the dentin and enamel. Teeth were randomly divided into two groups enamel and dentin (n=20). Each group was further divided into two subgroups; wet and dry samples (n=10). Each subgroup was divided according to the cement used, into resin cement or bioactive cement (n=5) and bonded to zirconia. Shear bond strength was determined, after thermo-cycling. Statistical analysis of the results showed that there was no statistically significant difference between shear bond strength of the two cement types either with wet enamel or dentin. With both cements, enamel showed statistically significantly higher mean shear bond strength than dentin. It was concluded that, both cements showed comparable results with significant superiority to the self-adhesive resin cement.
Study of dark electrical properties and photoelectric performance of organic/inorganic (ZnPc/p-Si) Solar cells
Authors: El Amin A A , Mahmoud M M 
Published: February 2021

Abstract
A Zinc Phthalocyanine (ZnPc) film was deposited by thermal evaporation on a monocrystalline p-Si substrate to provide a p-ZnPc/p-Si organic/inorganic heterojunction. The electrical characteristics of the fabricated cell were examined by measuring the current density versus voltage (J-V). The fabricated cell was characterized by a contact barrier of 0.56 eV and a rectification ratio of 230 calculated at ± 1 V−1. The dark J-V measurement suggested that the DC current density in this junction contains a thermionic conduction mechanism when the applied voltage is relatively low. At higher voltages another conduction is dominated called the space-charge limited conduction mechanism (SCLC) controlled by a single trapping level. The I-V measurement was performed with an illumination of 100 mWcm−2 and the photoelectric conversion characteristics of the junction were also studied, achieving a power conversion efficiency of 2.7%. The other solar cell parameters such as the short-circuit current Isc, the open-circuit voltage Voc and the filling factor FF were evaluated and equaled to 2.5 A, 1.132 V and 0.477 at room temperature. The dependence of these parameters as a function of the temperature has also been studied in the temperature range from 300 to 400 K.
Effect of stirring time on ZnO nanoparticles properties and morphology
Authors: Moghazy M A 
Published: February 2021

AbstractThe impact of stirring time on the ZnO nanoparticles assembly and properties as a novel study was investigated. A precipitation technique has been used for synthesizing ZnO nanoparticles and the impact of stirring time as well as calcination temperature and time were analyzed. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and Fourier-transform infrared spectroscopy (FTIR) were used for characterizing the resulting powder. The effect of stirring time, (viz., 0, 2, 4 and 6 h), on the optical properties was investigated using UV-Visible spectroscopy. The XRD analysis shown that all of the acquired powders had a pure form of ZnO nanoparticles with distinct crystallite size. The best circumstances for ZnO nanoparticle synthesis were 2h stirrings time and 400°C for 1 h, as calcination temperature and time, respectively. The FTIR spectra show that ZnO nanoparticles prepared at different stirring times appeared in wavenumber range 435.3 - 458.2 cm−1. SEM pictures reveal different surface distribution with some agglomeration through a variation on stirring time. The bandgap value was identical for 2 and 4 h stirring time with value 3.18 eV while, zero and 6 h stirring showing the same value with slight increase compared with 2 and 4 stirring to be 3.2 eV.
Microstructural changes and fracture resistance of nano-crystalline monolithic zirconia restorations upon aging
Authors: Kamel M H , Zaghloul H , Salah T , Ghanem L 
Published: February 2021

AbstractTo assess the effect of nano-modification of two CAD/CAM monolithic Zirconia systems (wet and dry-milled) on microstructural changes and fracture resistance upon aging. Twenty monolithic Zirconia discs (10mm x1.5mm) were divided into 2 groups (n=10) according to fabrication system;wet-milled (Incoris TZI) and dry-milled (CeramillZolid). Each group was subdivided into two subgroups (n=5), whether subjected to aging or not. Aging proceduresincluded accelerated hydrothermal aging and cyclic loading. Microstructural changes were assessed quantitatively and qualitatively using x-ray diffraction (XRD) and scanning electron microscope (SEM) respectively. Discs were subjected to fracture resistance test usinguniversal testing machine. Meansandstandard deviations were recorded for phase transformation (t-m)of Zirconia and repeated ANOVA was used to correlate phase transformation with fracture resistance results (p≤0.05). For aged subgroups, XRD analysis revealed significantly higher phase transformation of wet-milled than dry-milled (p≤0.05) and SEM analysis revealed wide zone phase transformation for wet-milled zirconia and minimal zone for dry-milled. For both systems, no significant difference between the mean flexural strength values ofnon-agedand aged zirconia (p≤0.05). Nanocrystalline microstructure of monolithic zirconia improved its resistance to aging. The fracture resistance of the two systems was not affected by aging.
A DFT investigation of anion-π interactions between halogen oxyanions (XO3
−, X = Cl, Br, I) and aromatic π-systems (benzene and coronene)
Authors: Elgengehi S M , El-Kelany Kh E , El-Taher S 
Published: February 2021

Abstract
Anion-π interactions have proved to play a key role in many chemical and biochemical phenomena. In order to investigate the nature and the applications of these interactions, the anion-π interactions of the chlorate (ClO3
−), bromate (BrO3
−), and iodate (IO3
−) oxyanions with benzene and coronene have been studied using density functional theory (DFT). The structures, adsorption energies, and electronic properties of XO3
−(X = Cl, Br, I) adsorbed on benzene and coronene have been explored using dispersion corrected DFT hybrid functional, M06-2X-D3, with the def2-TZVP basis set. Benzene and coronene have been respectively used as a building block and a simple flake of graphene. The interaction of these anions with benzene is found to be unexpectedly favorable. Their binding strength is further increased when the anions are adsorbed on coronene. Moreover, energy decomposition analysis based on symmetry adapted perturbation theory (SAPT) has been performed and the nature of interaction is characterized using noncovalent interaction analysis (NCI) based on reduced density gradient (RDG) method. Generally, the favorable binding of these anions with benzene or coronene is mainly ascribed to dispersion interactions. These anion-π interactions with graphene flakes or with benzene can be utilized in the design of anions receptors and detectors.
Monitoring of acoustic emission behaviour during early-age cement paste hydration
Authors: Shawkey M A , Abdelzaher M A , Mahmoud H M , Rashad M M 
Published: February 2021

Abstract
Valuation of Portland cement hydration using non-destructive techniques at early age is of great interest for predicting its thermal and durability characteristics. The acoustic emission (AE) technique is verified to be a high-quality non-destructive tool for real-time monitoring of structural micro-changes during the lifetime of Cement-based material composites. In this study, AE was applied to study the relationship between recorded signal and mechanisms that were happened during cement paste hydration. By using AE sensors, Portland cement paste samples with w/c ratio of 0.33 and 0.4 were explored during the first 72 h of casting. The AE resulting signals in each stage of hydration were studied to describe the various mechanisms that were running throughout the hydration process.
Antidiabetic effects of curcumin/zinc oxide nanocomposite in streptozotocin-induced diabetic rats
Authors: Abd El-Aziz S M , Raslan M , Afify M , Abdelmaksoud M D E , El-Nesr K A 
Published: February 2021

Abstract
Diabetes mellitus (DM) is a tremendously widespread endocrine disease that causes many complications risking patient’s quality of life. The current study aims to evaluate the antidiabetic potential of curcumin nanoparticles (Curc-NPs), Zinc Oxide nanoparticles (ZnO-NPs), and Curcumin/Zinc oxide nanocomposite (Curc/ZnO-NC) on streptozotocin (STZ)-induced diabetic rats. Results are compared to rats treated by traditional anti-diabetic Diamicron and to normal non-diabetic rats. Adult Wistar albino rats with weight (180-200 g) were divided into 6 groups, each group contains 8 rats (4 males and 4 females). To induce type 2 DM, five groups were injected intraperitoneal with a single dose of 50 mg/kg b.w. freshly prepared STZ. Each group of diabetic rats were treated orally with a daily dose of 50 mg/kg b.w. of Curc-NPs, 10 mg/kg b.w. of both ZnO-NPs & Curc/ZnO-NC, and 5 mg/kg b.w. of Diamicron for 21 days. The antidiabetic potential of every treatment against diabetic rats was evaluated by investigating different biochemical parameters (glucose, insulin, urea, creatinine, HbA1-C, AST, ALT) and histopathological parameters as well as protein expression of Glucokinase (GK) and Glucose transporter protein 2 (GLUT-2) in the pancreas and livers of diabetic rats. All treated groups showed significant reduction in blood glucose, elevated insulin levels, regulated GLUT-2 and GK genes, however, Curc/ZnO-NC showed the most potent anti-diabetic activity compared to normal rats, the histopathological findings correlate with the achieved data.
Effect of hydrothermal time and acid-washing on the antibacterial activity of Sodium titanate nanotubes
Authors: Mohamed H , Zaki A H , Abo El-Ela Fatma I , El-dek S I 
Published: February 2021

Abstract
Bacterial resistance to antibiotics has been a major concern globally. In this work, sodium and hydrogen titanate nanotubes were successfully synthesised using a facile hydrothermal technique. The prepared samples were characterized by XRD, FTIR, HRTEM surface area analyser, hydrodynamic size analyser and zeta potential. Minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) measurements besides agar well diffusion method showed good antimicrobial activity of both nanotubes. The antimicrobial activity of sodium titanate nanotubes prepared at 6 and 23 hr., and their hydrogen exchanged forms; (HTNT) and (HTNS) explored good antimicrobial activity against both Gram positive and Gram negative bacteria besides their antifungal activity which reflects their importance in treatment of bacterial infections causing serious diseases in both animal and human.
Effect of La doping on the structural and gas sensing properties of PbS thin films deposited by spray pyrolysis
Authors: Hamdedein A , Aboud A A , El Rouby W M A , Khan M D , Farghali A A , Khedr M H , Revaprasadu N 
Published: February 2021

Abstract
Phase pure PbS and lanthanum doped PbS thin films have been deposited by the spray pyrolysis technique. All the deposited films were gray to black, pin hole free and strongly adherent to the ITO glass substrates. The substrate temperature was varied between 450 and 500 °C, with doping concentration ratios of 1, 5 and 10% for La. The doping performed at 450 °C, showed phase segregation whereas successful incorporation of La in the PbS lattice was achieved at 500 °C. The films were characterized by x-ray diffraction (p-XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), Energy-dispersive X-ray spectroscopy (EDX), and ultraviolet visible spectroscopy (UV). The sensitivity of the as deposited thin films was also tested against hydrogen gas. The sensor material was exposed to a low concentration of 200 ppm of the target gas to determine the sensitivity performance of the sensor, at different temperatures while measuring the variation in the resistance. The doping of lanthanum significantly enhances the sensitivity of the PbS thin films against the target gas. The gas sensor exhibited n-type conductivity as confirmed by the decrease in resistance on exposure to hydrogen. The as prepared catalysts show good sensing behavior near room temperature and at low concentration of hydrogen at 200 ppm without the need to apply an external voltage.