Pub Date : 2021-10-09DOI: 10.21608/ejs.2021.96550.1021
Hanem Mohamed Ali, M. Amer, Asmaa Omaraa
Digital Fringe projection profilometry (DFPP) is a noncontact, fast, accurate and flexible technique for 3D measurements. Phase calculation is an important step that affects the accuracy of measurements. in phase calculation, the critical source of error is phase error due to nonlinear gamma effect of the system. This paper introduces an experimental investigation of the nonlinear gamma effect of DFPP system as well as the effect of system parameters, such as fringe intensity, fringe period, surface distance from the camera and projector and finally the ambient illumination, on phase error and consequently system measurements. Fringe patterns are generated using Matlab 2018a and projected by digital laser projector. The deformed patterns are captured using colored CCD camera. Phase shifting technique is used to calculate phase map. The system shows a linear response in the intensity range (50-220) and has small phase error without any compensation for nonlinear gamma effect. The phase error of the system slightly increases with increasing fringe period and the surface distance from the camera and projector, while it is nearly constant with ambient illumination changes from dark to median level and shows a bigger change if the ambient is completely illuminated. In the worst conditions the phase error does not accedes 0.0387 rad without any compensation for nonlinear gamma effect, make the system a useful tool for 3D measurements in different working fields.
{"title":"Effect of System Parameters on Phase Error of Focus-Free Digital Fringe Projection Profilometry System","authors":"Hanem Mohamed Ali, M. Amer, Asmaa Omaraa","doi":"10.21608/ejs.2021.96550.1021","DOIUrl":"https://doi.org/10.21608/ejs.2021.96550.1021","url":null,"abstract":"Digital Fringe projection profilometry (DFPP) is a noncontact, fast, accurate and flexible technique for 3D measurements. Phase calculation is an important step that affects the accuracy of measurements. in phase calculation, the critical source of error is phase error due to nonlinear gamma effect of the system. This paper introduces an experimental investigation of the nonlinear gamma effect of DFPP system as well as the effect of system parameters, such as fringe intensity, fringe period, surface distance from the camera and projector and finally the ambient illumination, on phase error and consequently system measurements. Fringe patterns are generated using Matlab 2018a and projected by digital laser projector. The deformed patterns are captured using colored CCD camera. Phase shifting technique is used to calculate phase map. The system shows a linear response in the intensity range (50-220) and has small phase error without any compensation for nonlinear gamma effect. The phase error of the system slightly increases with increasing fringe period and the surface distance from the camera and projector, while it is nearly constant with ambient illumination changes from dark to median level and shows a bigger change if the ambient is completely illuminated. In the worst conditions the phase error does not accedes 0.0387 rad without any compensation for nonlinear gamma effect, make the system a useful tool for 3D measurements in different working fields.","PeriodicalId":445633,"journal":{"name":"Egyptian Journal of Solids","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125582118","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}
Pub Date : 2021-10-01DOI: 10.21608/ejs.2021.93198.1019
E. Assim
The nanocrystalline Al-doped CdS semiconductors were produced accurately by the sol-gel calcination process. The aluminum was added with different percent’s (0, 1, 5, 10, 15, and 20 wt%) to the synthesized CdS. Both FT-Raman analysis and UV–VIS-NIR absorption measurements were utilized to characterize the studied semiconductors' structural and optical characteristics. The detected X-ray diffraction (XRD) patterns of the prepared CdS present a polycrystalline structure, and Al-doping does not significantly impact this range. Optical bandgaps were determined for undoped and Al-doped CdS, showing a significant change with the percentage of Al-dopants. With increasing Al-doping up to (20 percent), the optical bandgap for CdS (2.38 eV) grows to reach (2.47 eV) and the allowed transitions were found to be direct for the investigated samples. The blue shift may be the reason for the optical bandgap variations. Scanning Electron Microscope (SEM) micrographs were performed to establish the Al-doped CdS nanostructure to identify the morphological characteristics.
{"title":"Synthesis, structure, and optical properties of nanopowders CdS: xAl (x=0, 1, 5, 10, 15 and 20%) via the sol–gel technique","authors":"E. Assim","doi":"10.21608/ejs.2021.93198.1019","DOIUrl":"https://doi.org/10.21608/ejs.2021.93198.1019","url":null,"abstract":"The nanocrystalline Al-doped CdS semiconductors were produced accurately by the sol-gel calcination process. The aluminum was added with different percent’s (0, 1, 5, 10, 15, and 20 wt%) to the synthesized CdS. Both FT-Raman analysis and UV–VIS-NIR absorption measurements were utilized to characterize the studied semiconductors' structural and optical characteristics. The detected X-ray diffraction (XRD) patterns of the prepared CdS present a polycrystalline structure, and Al-doping does not significantly impact this range. Optical bandgaps were determined for undoped and Al-doped CdS, showing a significant change with the percentage of Al-dopants. With increasing Al-doping up to (20 percent), the optical bandgap for CdS (2.38 eV) grows to reach (2.47 eV) and the allowed transitions were found to be direct for the investigated samples. The blue shift may be the reason for the optical bandgap variations. Scanning Electron Microscope (SEM) micrographs were performed to establish the Al-doped CdS nanostructure to identify the morphological characteristics.","PeriodicalId":445633,"journal":{"name":"Egyptian Journal of Solids","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129271442","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}
Pub Date : 2021-09-04DOI: 10.21608/ejs.2021.90000.1017
A. Saeed, W. Abu-raia, M. Farag
White light emitters remain in the need of continual development and research for new materials. In this context, a low phonon energy glass containing Er3+ ions was prepared using the conventional melt/casting technique. The chemical compositions of the synthesized materials were analyzed using X-Ray Fluorescence (XRF) measurements. X-Ray Diffraction (XRD) pattern strongly affirms the non-crystalline essence of the produced materials. The behavior of both density and Fourier Transform Infrared (FTIR) spectroscopy denoted that the Er3+ ions have a modifier role and non-bridging oxygens NBOs were formed inside the studied glass network. The studied glasses have low phonon energy, ranging from 647 to 659 cm-1. The obtained results of the thermal, thermo-mechanical, mechanical, and optical properties were discussed in light of the structural changes brought about by inserting Er3+ ions inside the studied network. The present glasses have high thermal stability, high thermal expansion, and high refractive index. With the increase of Er3+ ion content, the Vickers microhardness VMH decreased from 3.78 GPa to 3.20 GPa. Under near ultraviolet NUV 380 nm excitation wavelength, three emission bands; blue, green, and red are observed. The white light is possible by a suitable combination of these colors. The cool white light emission was confirmed using CIE 1931 chromaticity diagram and correlated color temperature values. According to the obtained results, the studied glasses are nominated as a white light emitter in photonic applications.
{"title":"Er3+ ion doped low phonon energy glass as a white light emitter","authors":"A. Saeed, W. Abu-raia, M. Farag","doi":"10.21608/ejs.2021.90000.1017","DOIUrl":"https://doi.org/10.21608/ejs.2021.90000.1017","url":null,"abstract":"White light emitters remain in the need of continual development and research for new materials. In this context, a low phonon energy glass containing Er3+ ions was prepared using the conventional melt/casting technique. The chemical compositions of the synthesized materials were analyzed using X-Ray Fluorescence (XRF) measurements. X-Ray Diffraction (XRD) pattern strongly affirms the non-crystalline essence of the produced materials. The behavior of both density and Fourier Transform Infrared (FTIR) spectroscopy denoted that the Er3+ ions have a modifier role and non-bridging oxygens NBOs were formed inside the studied glass network. The studied glasses have low phonon energy, ranging from 647 to 659 cm-1. The obtained results of the thermal, thermo-mechanical, mechanical, and optical properties were discussed in light of the structural changes brought about by inserting Er3+ ions inside the studied network. The present glasses have high thermal stability, high thermal expansion, and high refractive index. With the increase of Er3+ ion content, the Vickers microhardness VMH decreased from 3.78 GPa to 3.20 GPa. Under near ultraviolet NUV 380 nm excitation wavelength, three emission bands; blue, green, and red are observed. The white light is possible by a suitable combination of these colors. The cool white light emission was confirmed using CIE 1931 chromaticity diagram and correlated color temperature values. According to the obtained results, the studied glasses are nominated as a white light emitter in photonic applications.","PeriodicalId":445633,"journal":{"name":"Egyptian Journal of Solids","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129862130","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}
Pub Date : 2021-06-01DOI: 10.21608/ejs.2021.98349.1022
S. Saafan, Enas Elghazzawy, Nagat M. Abo-aita
Polyethylene glycol (PEG)/nano-ferrite composites have been prepared by using CoFe2O4, CuFe2O4, Co0.5Cu0.5Fe2O4 and MgFe2O4 ferrite nano-particles synthesized by citrate precursor method along with PEG with different percentages. Ferrite samples have been characterized by X-ray diffraction (XRD) to confirm the formation of pure spinel ferrite phase and, transmission electron microscopy (TEM) to ensure that the average particle size is within the nano-scale. Thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC) thermographs of the ferrite samples have been used to ensure the complete formation of pure ferrites at temperatures above 800 o C. The ferrites and their composites with PEG, have been investigated by FTIR spectroscopy. The main bands of ferrites and PEG have been clearly displayed in agreement with literature. A systematic shift of the bands has been observed upon adding PEG. The magnetic properties have been explored by using the vibrating sample magnetometer (VSM). Where the values of of saturation magnetization (Ms), remnant magnetization (Mr) and coercive field (Hc) for pure ferrite and composite samples vary with the presence of different divalent cations which have different magnetic moment. Whereas, Hc values remain constant as obtained in pure ferrites regardless the ratio of PEG. The obtained values of Hc are comparable with those in literature, which can be used in electromagnetic wave attenuation.
{"title":"Preparation and structural investigation of Polyethylene glycol (PEG) / nano-ferrite composites","authors":"S. Saafan, Enas Elghazzawy, Nagat M. Abo-aita","doi":"10.21608/ejs.2021.98349.1022","DOIUrl":"https://doi.org/10.21608/ejs.2021.98349.1022","url":null,"abstract":"Polyethylene glycol (PEG)/nano-ferrite composites have been prepared by using CoFe2O4, CuFe2O4, Co0.5Cu0.5Fe2O4 and MgFe2O4 ferrite nano-particles synthesized by citrate precursor method along with PEG with different percentages. Ferrite samples have been characterized by X-ray diffraction (XRD) to confirm the formation of pure spinel ferrite phase and, transmission electron microscopy (TEM) to ensure that the average particle size is within the nano-scale. Thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC) thermographs of the ferrite samples have been used to ensure the complete formation of pure ferrites at temperatures above 800 o C. The ferrites and their composites with PEG, have been investigated by FTIR spectroscopy. The main bands of ferrites and PEG have been clearly displayed in agreement with literature. A systematic shift of the bands has been observed upon adding PEG. The magnetic properties have been explored by using the vibrating sample magnetometer (VSM). Where the values of of saturation magnetization (Ms), remnant magnetization (Mr) and coercive field (Hc) for pure ferrite and composite samples vary with the presence of different divalent cations which have different magnetic moment. Whereas, Hc values remain constant as obtained in pure ferrites regardless the ratio of PEG. The obtained values of Hc are comparable with those in literature, which can be used in electromagnetic wave attenuation.","PeriodicalId":445633,"journal":{"name":"Egyptian Journal of Solids","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121844486","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}
Pub Date : 2021-06-01DOI: 10.21608/ejs.2021.69568.1010
Nourhan Badawy
A mathematical model for investigating warm performance of the ventured sunlight based still which is not performed in most of the previous studies. is developed in this study. Based on the proposed model, a computer program (using Pascal language) is carried out. A stepped solar still consists of five small steps(0.002 m depth, 0.2 m width and 1.0 m length). The effect of configuration parameters on the stepped productivity and efficiency such as the still width (b_s), depth of water (d_w), tray width (W) and the height of tray (H) is considered. Comparing thermal performance of the stepped solar still with that of the conventional one shows that the stepped solar still is more efficient. Correlations of the got results with those introduced in the past investigations have been done, prompt an approving the proposed mathematical model. The outcomes show that, the every day productivities for the traditional and ventured sun based stills are discovered to be 4.0 and 4.51 (kg/m2day); separately. The Daily productivity of the regular and ventured sunlight based stills are 61.48% and 81.85%, individually.
{"title":"Mathematical modeling of the heat exchange in a stepped solar still","authors":"Nourhan Badawy","doi":"10.21608/ejs.2021.69568.1010","DOIUrl":"https://doi.org/10.21608/ejs.2021.69568.1010","url":null,"abstract":"A mathematical model for investigating warm performance of the ventured sunlight based still which is not performed in most of the previous studies. is developed in this study. Based on the proposed model, a computer program (using Pascal language) is carried out. A stepped solar still consists of five small steps(0.002 m depth, 0.2 m width and 1.0 m length). The effect of configuration parameters on the stepped productivity and efficiency such as the still width (b_s), depth of water (d_w), tray width (W) and the height of tray (H) is considered. Comparing thermal performance of the stepped solar still with that of the conventional one shows that the stepped solar still is more efficient. Correlations of the got results with those introduced in the past investigations have been done, prompt an approving the proposed mathematical model. The outcomes show that, the every day productivities for the traditional and ventured sun based stills are discovered to be 4.0 and 4.51 (kg/m2day); separately. The Daily productivity of the regular and ventured sunlight based stills are 61.48% and 81.85%, individually.","PeriodicalId":445633,"journal":{"name":"Egyptian Journal of Solids","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122000125","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}
Pub Date : 2021-05-30DOI: 10.21608/EJS.2021.64685.1002
A. Ghoneim
Ultrafine Ni0.1Co0.9Fe2O4 nanocrystals were synthesized by the simple co-precipitation route, and well-accurately characterized by X-ray diffraction (XRD), FT-IR spectra, and high resolution transmission electron microscopy (HTEM) technique. XRD investigation proved the evolution of the single-phase cubic spinel structure for these nanocrystals. The fine crystallite size R average value was 36.265 nm. FT-IR absorption spectra displayed the essential absorption bands that were related to their principle sites and main bonds. All the deduced parameters were affected by the presence of the Ni2+, Co2+, and Fe3+ cations in these nanocrystals. HTEM images showed accumulations for the nanoparticles, where the average particle size value was 42.9 nm and was slightly higher than the crystallite size R. Evaluation of photocatalytic activity for Ni0.1Co0.9Fe2O4 Nano-ferrites was obtained through the degradation of Crystal Violet (CV) dye (1 × 10-5 M) in aqueous solution under visible light irradiation using 100 Watt Tungsten lamp fixed at ~ 10 cm distance. As a result, usage of these new ultrafine Ni0.1Co0.9Fe2O4 nanocrystals gives a new marvellous route for the advancement of cost-effective technologies for quite good waste water recycling models, for raising water quality and for the promotion of fruitful efforts in improving treatment systems.
{"title":"Utilization of the Ni0.1Co0.9Fe2O4 Nanocrystals for the Degradation of Crystal Violet","authors":"A. Ghoneim","doi":"10.21608/EJS.2021.64685.1002","DOIUrl":"https://doi.org/10.21608/EJS.2021.64685.1002","url":null,"abstract":"Ultrafine Ni0.1Co0.9Fe2O4 nanocrystals were synthesized by the simple co-precipitation route, and well-accurately characterized by X-ray diffraction (XRD), FT-IR spectra, and high resolution transmission electron microscopy (HTEM) technique. XRD investigation proved the evolution of the single-phase cubic spinel structure for these nanocrystals. The fine crystallite size R average value was 36.265 nm. FT-IR absorption spectra displayed the essential absorption bands that were related to their principle sites and main bonds. All the deduced parameters were affected by the presence of the Ni2+, Co2+, and Fe3+ cations in these nanocrystals. HTEM images showed accumulations for the nanoparticles, where the average particle size value was 42.9 nm and was slightly higher than the crystallite size R. Evaluation of photocatalytic activity for Ni0.1Co0.9Fe2O4 Nano-ferrites was obtained through the degradation of Crystal Violet (CV) dye (1 × 10-5 M) in aqueous solution under visible light irradiation using 100 Watt Tungsten lamp fixed at ~ 10 cm distance. As a result, usage of these new ultrafine Ni0.1Co0.9Fe2O4 nanocrystals gives a new marvellous route for the advancement of cost-effective technologies for quite good waste water recycling models, for raising water quality and for the promotion of fruitful efforts in improving treatment systems.","PeriodicalId":445633,"journal":{"name":"Egyptian Journal of Solids","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131295128","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}
Pub Date : 2020-10-01DOI: 10.21608/ejs.2020.148115
{"title":"Influence of Small Amount of Cu Addition on Microstructure, Deformation Temperature, and the Tensile Behaviour of Sn-9Zn-1.5Ag Lead free Solder Alloy","authors":"","doi":"10.21608/ejs.2020.148115","DOIUrl":"https://doi.org/10.21608/ejs.2020.148115","url":null,"abstract":"","PeriodicalId":445633,"journal":{"name":"Egyptian Journal of Solids","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122589315","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}
Pub Date : 2020-10-01DOI: 10.21608/ejs.2020.148113
{"title":"Thermal and Mechanical Properties of Oxyfluorophosphate Glass Containing Er3+/Yb3+","authors":"","doi":"10.21608/ejs.2020.148113","DOIUrl":"https://doi.org/10.21608/ejs.2020.148113","url":null,"abstract":"","PeriodicalId":445633,"journal":{"name":"Egyptian Journal of Solids","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122381078","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}
Pub Date : 2018-10-01DOI: 10.21608/ejs.2018.148256
A. A. Zaki
Optical properties of the difluoro substituted 4-(2-(or 3) fluoro phenylazo (-2’-(or 3’-) fluoro phenyl-4-dodecyloxybenzoates thermotropic liquid crystal (III) were affected by the special new position and orientation of the two fluorine atoms. The compound III was dissolved in methylene chloride of different concentrations in order to determine its absorbance and transmittance in UV-visible region at room temperature. The maximum absorbance for the compound was in the blue region (447nm) and the molar absorption coefficient was found to be 0.93 (L. mMol.cm). The phase transition temperature was determined for the thermotropic LC compound III by using DSC, POM and modified spectrophotometer techniques as a new method. Nematic and smectic A phases during cooling process were observed. Refractive indices, birefringence, order parameter were measured. The molecular polarizability was determined also with different temperatures for the LC phases of compound III.
{"title":"Optical Properties and Phase Transition Measurements of Oriented Difluorophenylazophenyl Benzoate Liquid Crystal","authors":"A. A. Zaki","doi":"10.21608/ejs.2018.148256","DOIUrl":"https://doi.org/10.21608/ejs.2018.148256","url":null,"abstract":"Optical properties of the difluoro substituted 4-(2-(or 3) fluoro phenylazo (-2’-(or 3’-) fluoro phenyl-4-dodecyloxybenzoates thermotropic liquid crystal (III) were affected by the special new position and orientation of the two fluorine atoms. The compound III was dissolved in methylene chloride of different concentrations in order to determine its absorbance and transmittance in UV-visible region at room temperature. The maximum absorbance for the compound was in the blue region (447nm) and the molar absorption coefficient was found to be 0.93 (L. mMol.cm). The phase transition temperature was determined for the thermotropic LC compound III by using DSC, POM and modified spectrophotometer techniques as a new method. Nematic and smectic A phases during cooling process were observed. Refractive indices, birefringence, order parameter were measured. The molecular polarizability was determined also with different temperatures for the LC phases of compound III.","PeriodicalId":445633,"journal":{"name":"Egyptian Journal of Solids","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124785755","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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