In this paper, a Bianchi type V Dark energy cosmological model scenario is studied with the electromagnetic field in Lyra based on f(R,T) gravity. The source of the magnetic field is along the x axis. Field equations found in Lyra geometry with electromagnetic field (F23 ≠ 0) in f(R,T) gravity, by choosing f(R~,T) = f1(R~) + f2(T) with f1(R~) + μR~ and f2(T) = μT. A hybrid scale factor discusses the physical and dynamical aspects of f(R,T) gravity.
{"title":"Role of f(R,T) Gravity in Bianchi Type-V Dark Energy Model with Electromagnetic Field based on Lyra Geometry","authors":"B. P. Brahma, M. Dewri","doi":"10.3329/jsr.v14i3.56416","DOIUrl":"https://doi.org/10.3329/jsr.v14i3.56416","url":null,"abstract":"In this paper, a Bianchi type V Dark energy cosmological model scenario is studied with the electromagnetic field in Lyra based on f(R,T) gravity. The source of the magnetic field is along the x axis. Field equations found in Lyra geometry with electromagnetic field (F23 ≠ 0) in f(R,T) gravity, by choosing f(R~,T) = f1(R~) + f2(T) with f1(R~) + μR~ and f2(T) = μT. A hybrid scale factor discusses the physical and dynamical aspects of f(R,T) gravity.","PeriodicalId":16984,"journal":{"name":"JOURNAL OF SCIENTIFIC RESEARCH","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86062234","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}
We present a new and elegant method of derivation of the gravitomagnetic clock effect using gravitational Lorentz force, which appears in gravitoelectromagnetism. The result is precisely the same as that of general relativity in the Kerr field.
{"title":"Gravitoelectromagnetism and Gravitomagnetic Clock Effect","authors":"B. K. Chakravorti, S. B. Faruque","doi":"10.3329/jsr.v14i3.57972","DOIUrl":"https://doi.org/10.3329/jsr.v14i3.57972","url":null,"abstract":"We present a new and elegant method of derivation of the gravitomagnetic clock effect using gravitational Lorentz force, which appears in gravitoelectromagnetism. The result is precisely the same as that of general relativity in the Kerr field.","PeriodicalId":16984,"journal":{"name":"JOURNAL OF SCIENTIFIC RESEARCH","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89788292","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}
This paper deals with a similarity solution of unsteady magneto hydrodynamics two-dimensional boundary layer flow of a nanofluid for free convection past an inclined plate. Using similarity transformations, the governing equations are reduced into a set of non-linear ordinary differential equations. The transformed dimensionless equations are then solved numerically using the Nachtsheim-Swigert iteration technique and the order Runga-Kutta method. The effects of buoyancy-ratio parameter, Magnetic parameter, Brownian motion parameter, Thermophoresis parameter, Brownian diffusion parameter, unsteadiness, and other driving parameters on the velocity profile, temperature profile, and concentration profile are represented graphically and discussed in detail. The numerical values of several involved parameters on Skin-friction co-efficient, local Nusselt, and Sherwood numbers are presented in tabular form.
{"title":"Effects on Unsteady MHD Flow of a Nanofluid for Free Convection past an Inclined Plate","authors":"S. M. Gani, M. Y. Ali, M. A. Islam","doi":"10.3329/jsr.v14i3.58301","DOIUrl":"https://doi.org/10.3329/jsr.v14i3.58301","url":null,"abstract":"This paper deals with a similarity solution of unsteady magneto hydrodynamics two-dimensional boundary layer flow of a nanofluid for free convection past an inclined plate. Using similarity transformations, the governing equations are reduced into a set of non-linear ordinary differential equations. The transformed dimensionless equations are then solved numerically using the Nachtsheim-Swigert iteration technique and the order Runga-Kutta method. The effects of buoyancy-ratio parameter, Magnetic parameter, Brownian motion parameter, Thermophoresis parameter, Brownian diffusion parameter, unsteadiness, and other driving parameters on the velocity profile, temperature profile, and concentration profile are represented graphically and discussed in detail. The numerical values of several involved parameters on Skin-friction co-efficient, local Nusselt, and Sherwood numbers are presented in tabular form.","PeriodicalId":16984,"journal":{"name":"JOURNAL OF SCIENTIFIC RESEARCH","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89165652","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}
Composites of nanometre-sized copper core–copper oxide (Cu-Cu2O) shell with different diameters were synthesized by a facile one step co-solvent technique. By the analysis of X-ray diffraction (XRD) and transmission electron microscope (TEM) data, the resultant particles were confirmed to be pure and nanocrystalline in nature. The perfect core-shell structure of nanocrystalline Cu-Cu2O was confirmed by using high resolution TEM. The presence of pure Cu and Cu2O was further confirmed from optical absorbance spectrum and Fourier transform infrared (FT-IR) spectroscopy. The tailoring of position of optical absorption peaks, originating from Cu or Cu2O nanoparticles, is possible by modulating the oil to water ratio, which controls the size of the composite particles and thickness of Cu2O. Drastic change of electrical resistivity with change in thickness of shell, has been observed. Variation of resistivity with temperature delineates a semiconducting nature with two distinct activation processes. Results demonstrate that the activation energies for the core-shell nanostructure composites were found to be smaller than the bulk Cu2O. Photoluminescence spectrum further confirms the semiconducting nature of the composite. In addition, the kinetic of core-shell morphology formation is also discussed briefly.
{"title":"Microstructure, Optical and Electrical Properties of Cu-Cu2O Core-Shell Nanostructures","authors":"O. Mondal","doi":"10.3329/jsr.v14i3.58384","DOIUrl":"https://doi.org/10.3329/jsr.v14i3.58384","url":null,"abstract":"Composites of nanometre-sized copper core–copper oxide (Cu-Cu2O) shell with different diameters were synthesized by a facile one step co-solvent technique. By the analysis of X-ray diffraction (XRD) and transmission electron microscope (TEM) data, the resultant particles were confirmed to be pure and nanocrystalline in nature. The perfect core-shell structure of nanocrystalline Cu-Cu2O was confirmed by using high resolution TEM. The presence of pure Cu and Cu2O was further confirmed from optical absorbance spectrum and Fourier transform infrared (FT-IR) spectroscopy. The tailoring of position of optical absorption peaks, originating from Cu or Cu2O nanoparticles, is possible by modulating the oil to water ratio, which controls the size of the composite particles and thickness of Cu2O. Drastic change of electrical resistivity with change in thickness of shell, has been observed. Variation of resistivity with temperature delineates a semiconducting nature with two distinct activation processes. Results demonstrate that the activation energies for the core-shell nanostructure composites were found to be smaller than the bulk Cu2O. Photoluminescence spectrum further confirms the semiconducting nature of the composite. In addition, the kinetic of core-shell morphology formation is also discussed briefly.\u0000","PeriodicalId":16984,"journal":{"name":"JOURNAL OF SCIENTIFIC RESEARCH","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74794734","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}
In this paper, authors propose a new integral transform “Rishi Transform” with application to determine the exact (analytic) solution of first kind Volterra integral equation (V.I.E.). For this purpose, authors first derived the Rishi transform of basic mathematical functions (algebraic and transcendential) and then the fundamental properties of Rishi transform is discussed, which can be used for solving ordinary differential equations (O.D.E), partial differential equations (P.D.E.), delay differential equations (D.D.E.), fractional differential equations (F.D.E.), difference equations (D.E.), integral equations (I.E.) and integro-differential equations (I.D.E.). After this, authors determined the exact (analytic) solution of general first kind V.I.E.. They have considered three numerical problems and solved them completely step by step for explaining the utility of Rishi transform. Results depict that the proposed new integral transform "Rishi Transform" provides the exact results for first kind V.I.E. without doing complicated calculation work.
{"title":"A New Integral Transform “Rishi Transform” with Application","authors":"R. Kumar, J. Chandel, S. Aggarwal","doi":"10.3329/jsr.v14i2.56545","DOIUrl":"https://doi.org/10.3329/jsr.v14i2.56545","url":null,"abstract":"In this paper, authors propose a new integral transform “Rishi Transform” with application to determine the exact (analytic) solution of first kind Volterra integral equation (V.I.E.). For this purpose, authors first derived the Rishi transform of basic mathematical functions (algebraic and transcendential) and then the fundamental properties of Rishi transform is discussed, which can be used for solving ordinary differential equations (O.D.E), partial differential equations (P.D.E.), delay differential equations (D.D.E.), fractional differential equations (F.D.E.), difference equations (D.E.), integral equations (I.E.) and integro-differential equations (I.D.E.). After this, authors determined the exact (analytic) solution of general first kind V.I.E.. They have considered three numerical problems and solved them completely step by step for explaining the utility of Rishi transform. Results depict that the proposed new integral transform \"Rishi Transform\" provides the exact results for first kind V.I.E. without doing complicated calculation work.","PeriodicalId":16984,"journal":{"name":"JOURNAL OF SCIENTIFIC RESEARCH","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87509613","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 microstrip patch antenna is considered the most suitable radiating and receiving element for millimeter-wave application due to its low cost, simple construction, low weight, and ease with which it is integrated into the circuits. In this paper, we have reported the effects of different symmetric shaped slots on millimeter-wave patch antenna design and its performance at 10 GHz frequency in the X band (8-12 GHZ). The rectangular, circular, and elliptical slots area is kept constant at 11.2 mm2. The radius of circular and spherical slots is the same. High-frequency simulation software (HFSS) simulation results in parameters like S11 (reflection coefficient), Y-parameter (driving point admittance), Radiation Pattern, 3D Polar plot and illustrate that the results are in good agreement with the desired value. A rectangular slot is found to achieve the target resonance frequency with a low voltage standing wave ratio (VSWR) towards a ‘good match.’ Circular, spherical, and elliptical-shaped slots have high VSWR values, indicating a larger degree of mismatch. Surprisingly, results are obtained for the spherical-shaped slot, implying that the antenna will work at the target resonance frequency and has a Dual-Resonance. The proposed antenna design is suitable for 5G device applications in the X band.
{"title":"Effect of Symmetric Shaped Slot on Patch Antenna Design and Performance for 10 GHz 5G Applications","authors":"K. K. Giri, R. Singh, K. Mamta","doi":"10.3329/jsr.v14i2.55209","DOIUrl":"https://doi.org/10.3329/jsr.v14i2.55209","url":null,"abstract":"A microstrip patch antenna is considered the most suitable radiating and receiving element for millimeter-wave application due to its low cost, simple construction, low weight, and ease with which it is integrated into the circuits. In this paper, we have reported the effects of different symmetric shaped slots on millimeter-wave patch antenna design and its performance at 10 GHz frequency in the X band (8-12 GHZ). The rectangular, circular, and elliptical slots area is kept constant at 11.2 mm2. The radius of circular and spherical slots is the same. High-frequency simulation software (HFSS) simulation results in parameters like S11 (reflection coefficient), Y-parameter (driving point admittance), Radiation Pattern, 3D Polar plot and illustrate that the results are in good agreement with the desired value. A rectangular slot is found to achieve the target resonance frequency with a low voltage standing wave ratio (VSWR) towards a ‘good match.’ Circular, spherical, and elliptical-shaped slots have high VSWR values, indicating a larger degree of mismatch. Surprisingly, results are obtained for the spherical-shaped slot, implying that the antenna will work at the target resonance frequency and has a Dual-Resonance. The proposed antenna design is suitable for 5G device applications in the X band.","PeriodicalId":16984,"journal":{"name":"JOURNAL OF SCIENTIFIC RESEARCH","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87046027","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}
In this paper, the problem of unsteady two-dimensional boundary layer heat and mass transfer flow over an exponentially stretching sheet embedded in a porous medium in the presence of a uniform magnetic field with thermal radiation, heat generation/absorption, and suction/blowing is analyzed numerically. Instead of no-slip boundary conditions, velocity slip, thermal slip, and mass slips at the boundary are considered. Using a suitable similarity transformation, the governing partial differential equations are transformed to a system coupled with nonlinear ordinary differential equations. The reduced equations are solved numerically by using bvp4c with the MATLAB package. A detailed parametric study is performed to illustrate the physical parameters on the velocity, temperature, and concentration profile and the local skin-friction coefficient and Nusselt and Sherwood number. Then the results are exhibited in both graphical and tabular forms. It is observed that the present results have been in close agreement with the previously published studies under some special cases.
{"title":"Unsteady Heat and Mass Transfer Slip Flow over an Exponentially Permeable Stretching Sheet","authors":"M. A. Islam, M. Y. Ali, S. M. Gani","doi":"10.3329/jsr.v14i2.55577","DOIUrl":"https://doi.org/10.3329/jsr.v14i2.55577","url":null,"abstract":"In this paper, the problem of unsteady two-dimensional boundary layer heat and mass transfer flow over an exponentially stretching sheet embedded in a porous medium in the presence of a uniform magnetic field with thermal radiation, heat generation/absorption, and suction/blowing is analyzed numerically. Instead of no-slip boundary conditions, velocity slip, thermal slip, and mass slips at the boundary are considered. Using a suitable similarity transformation, the governing partial differential equations are transformed to a system coupled with nonlinear ordinary differential equations. The reduced equations are solved numerically by using bvp4c with the MATLAB package. A detailed parametric study is performed to illustrate the physical parameters on the velocity, temperature, and concentration profile and the local skin-friction coefficient and Nusselt and Sherwood number. Then the results are exhibited in both graphical and tabular forms. It is observed that the present results have been in close agreement with the previously published studies under some special cases.","PeriodicalId":16984,"journal":{"name":"JOURNAL OF SCIENTIFIC RESEARCH","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74987053","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}
Graphene has attracted great attention to researchers nowadays for its electronic, optical, and mechanical properties. A key requirement for applications is the development of industrial-scale, reliable, and inexpensive production processes. In this work, we present a scalable approach of graphene synthesis from a biomass source such as hemp bat fiber which is called hemp bast fiber derived graphene (HGr). The structure and morphology of HGr are confirmed by performing several characterization techniques such as XRD, Raman spectroscopy, and TEM analysis. Mesoporosity of the HGr is confirmed by BET surface area and BJH pore size distribution analysis.
{"title":"Synthesis Method of Hemp-Derived Graphene","authors":"M. Z. Hossain, S. Sutradhar, M. R. Karim","doi":"10.3329/jsr.v14i2.55694","DOIUrl":"https://doi.org/10.3329/jsr.v14i2.55694","url":null,"abstract":"Graphene has attracted great attention to researchers nowadays for its electronic, optical, and mechanical properties. A key requirement for applications is the development of industrial-scale, reliable, and inexpensive production processes. In this work, we present a scalable approach of graphene synthesis from a biomass source such as hemp bat fiber which is called hemp bast fiber derived graphene (HGr). The structure and morphology of HGr are confirmed by performing several characterization techniques such as XRD, Raman spectroscopy, and TEM analysis. Mesoporosity of the HGr is confirmed by BET surface area and BJH pore size distribution analysis.","PeriodicalId":16984,"journal":{"name":"JOURNAL OF SCIENTIFIC RESEARCH","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88932422","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}
In this paper, we have studied Bianchi type metric in Lyra's geometry with scalar field and flat potential. The Einstein's field equations have been solved by taking the shear scalar in the model proportional to the expansion scalar, which leads to A = Bn, where A and B are metric functions and n is a positive constant. Also, we discuss some physical and geometrical features of the obtaining model.
{"title":"Bianchi Type-VI0 Inflationary Model in Lyra Geometry","authors":"P. Lambat, A. M. Pund","doi":"10.3329/jsr.v14i2.55557","DOIUrl":"https://doi.org/10.3329/jsr.v14i2.55557","url":null,"abstract":"In this paper, we have studied Bianchi type metric in Lyra's geometry with scalar field and flat potential. The Einstein's field equations have been solved by taking the shear scalar in the model proportional to the expansion scalar, which leads to A = Bn, where A and B are metric functions and n is a positive constant. Also, we discuss some physical and geometrical features of the obtaining model.","PeriodicalId":16984,"journal":{"name":"JOURNAL OF SCIENTIFIC RESEARCH","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88382000","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}
Gamma irradiation of Gelatin brings important changes in its chemical structure, making it suitable for different applications. The irradiated Gelatin may be subjected to different thermal treatments during these applications. Therefore, temperature-dependent changes in irradiated gelatins are a point of interest. Electron spin resonance (ESR) is vital for detecting free radical processes in irradiated polymers. As such, ESR spectra of temperature-dependent porcine Gelatin with low bloom are recorded, and they are analyzed by computer simulation techniques. Component spectra under different conditions are evaluated by the magnetic parameters employed to simulate the ESR spectra. The results indicate that the spectral shape at 300 K (RT) is stable up to 350 K, and signal intensity begins to decay beyond 350 K. The signal vanished around 355 K, designated as radical decay temperature. Bloch analysis is applied to evaluate activation energy associated with free radical decay, calculated around 35 KJ/mole.
明胶经γ射线辐照后，其化学结构发生了重要变化，使其适用于不同的用途。在这些应用过程中，辐照明胶可经受不同的热处理。因此，辐照明胶的温度依赖性变化是一个值得关注的问题。电子自旋共振(ESR)是检测辐照聚合物中自由基过程的重要手段。因此，记录了低华度温度依赖性猪明胶的ESR光谱，并利用计算机模拟技术对其进行了分析。利用磁参数模拟ESR谱，对不同条件下的组分谱进行了评价。结果表明，300 K (RT)下的光谱形状在350 K以下是稳定的，超过350 K后信号强度开始衰减。信号在355k左右消失，这被称为自由基衰变温度。布洛赫分析用于评估与自由基衰变相关的活化能，计算结果约为35 KJ/mol。
{"title":"Temperature-Dependent Changes in Gamma Irradiated Porcine Gelatin with Low Bloom (PGL) Value: an ESR Investigation","authors":"N. S. Rao, D. Shireesh, S. Kalahasti, B. S. Rao","doi":"10.3329/jsr.v14i2.55078","DOIUrl":"https://doi.org/10.3329/jsr.v14i2.55078","url":null,"abstract":"Gamma irradiation of Gelatin brings important changes in its chemical structure, making it suitable for different applications. The irradiated Gelatin may be subjected to different thermal treatments during these applications. Therefore, temperature-dependent changes in irradiated gelatins are a point of interest. Electron spin resonance (ESR) is vital for detecting free radical processes in irradiated polymers. As such, ESR spectra of temperature-dependent porcine Gelatin with low bloom are recorded, and they are analyzed by computer simulation techniques. Component spectra under different conditions are evaluated by the magnetic parameters employed to simulate the ESR spectra. The results indicate that the spectral shape at 300 K (RT) is stable up to 350 K, and signal intensity begins to decay beyond 350 K. The signal vanished around 355 K, designated as radical decay temperature. Bloch analysis is applied to evaluate activation energy associated with free radical decay, calculated around 35 KJ/mole.","PeriodicalId":16984,"journal":{"name":"JOURNAL OF SCIENTIFIC RESEARCH","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72576292","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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