Abstract We focus on new expressions for the Aharonov–Bohm (AB) phase proposed recently by C. Marletto and V. Vedral (Phys. Rev. Lett. 125, 040401 (2020)) and by our team (A. L. Kholmetskii et al., Ann. Phys., 434, 168627 (2021)). We emphasize the mismatch between the standard expression for the electric component of the AB phase and the expression by Marletto and Vedral for this component, which, as we show, has fundamental roots and indicates the need to use different expressions for the Hamiltonian of the radiative component and bound component of the electromagnetic (EM) field. We further show that the corrected expression for the AB phase of Marletto and Vedral and our expression for the AB phase do not coincide with its standard representation through the potentials of EM field (Y. Aharonov, D. Bohm, Phys. Rev. 115 (1959) 485) and contain additional terms, which straightforwardly allow to re-express the AB phase via electric and magnetic fields instead of scalar and vector potentials. The recognition of the field-dependent origin of the AB effect also requires to re-express the Hamiltonian of a charged particle through the EM field, which we show can be done in the only possible way. We discuss the physical meaning of the AB effect with the primary role of the EM field and also discuss some general quantum mechanical implications.
摘要 我们重点讨论最近由 C. Marletto 和 V. Vedral（Phys. Rev. Lett.125, 040401 (2020)）和我们团队（A. L. Kholmetskii et al.Phys., 434, 168627 (2021)）。我们强调了 AB 相电分量的标准表达式与 Marletto 和 Vedral 对该分量的表达式之间的不匹配，正如我们所展示的，这种不匹配具有根本性的根源，并表明需要对电磁场的辐射分量和束缚分量的哈密尔顿使用不同的表达式。我们进一步证明，Marletto 和 Vedral 的 AB 相修正表达式和我们的 AB 相表达式与通过电磁场势（Y. Aharonov, D. Bohm, Phys. Rev. 115 (1959) 485）的标准表达式并不一致，而是包含了附加项，可以直接通过电场和磁场而不是标量和矢量势来重新表达 AB 相。要认识到 AB 效应的场依赖性起源，还需要通过电磁场重新表达带电粒子的哈密顿，我们证明这是唯一可能的方法。我们讨论了以电磁场为主要作用的 AB 效应的物理意义，还讨论了一些一般量子力学含义。
{"title":"New expressions for the Aharonov–Bohm phase and consequences for the fundamentals of quantum mechanics","authors":"A. Kholmetskii, T. Yarman, O. Missevitch","doi":"10.1515/zna-2023-0297","DOIUrl":"https://doi.org/10.1515/zna-2023-0297","url":null,"abstract":"Abstract We focus on new expressions for the Aharonov–Bohm (AB) phase proposed recently by C. Marletto and V. Vedral (Phys. Rev. Lett. 125, 040401 (2020)) and by our team (A. L. Kholmetskii et al., Ann. Phys., 434, 168627 (2021)). We emphasize the mismatch between the standard expression for the electric component of the AB phase and the expression by Marletto and Vedral for this component, which, as we show, has fundamental roots and indicates the need to use different expressions for the Hamiltonian of the radiative component and bound component of the electromagnetic (EM) field. We further show that the corrected expression for the AB phase of Marletto and Vedral and our expression for the AB phase do not coincide with its standard representation through the potentials of EM field (Y. Aharonov, D. Bohm, Phys. Rev. 115 (1959) 485) and contain additional terms, which straightforwardly allow to re-express the AB phase via electric and magnetic fields instead of scalar and vector potentials. The recognition of the field-dependent origin of the AB effect also requires to re-express the Hamiltonian of a charged particle through the EM field, which we show can be done in the only possible way. We discuss the physical meaning of the AB effect with the primary role of the EM field and also discuss some general quantum mechanical implications.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"51 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139379990","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}
Abstract In this article, a partial differential equation (PDE) model for atherosclerosis disease is presented that analyzes the anti-oxidative activity of high-density lipoprotein (HDL) during the reverse cholesterol transport (RCT) process. The model thoroughly investigates the complex interplay between oxidized low-density lipoprotein (ox-LDL) and high-density lipoprotein in the context of atherosclerosis, emphasizing their combined impact on plaque formation, disease progression, and regression. In addition to this, we considered that monocytes are also attracted by the presence of ox-LDL within the intima. Detailed discussions on stability analyses of the reaction dynamical system at non-inflammatory and chronic equilibrium are provided, followed by a bifurcation analysis for the proposed system. Furthermore, stability analysis for the PDE model in the presence of diffusion is conducted. Our study reveals that the oxidation rate of LDL by monocytes (δ) and the influx rate of HDL (ϕ) due to drugs/diet are primarily responsible for the existence of bi-stability of equilibrium points. In the numerical results, we observe that non-inflammatory or chronic equilibrium points exist for either a short or a long time, and these findings are validated with existing results. The biological elucidation shows the novelty in terms of enhancing our ability to assess intervention efficacy to generate therapeutic strategies resulting in the reduction of the atherosclerotic burden and associated cardiovascular risks.
{"title":"Bifurcation and stability analysis of atherosclerosis disease model characterizing the anti-oxidative activity of HDL during short- and long-time evolution","authors":"Asish Adak, Debasmita Mukherjee, Praveen Kumar Gupta","doi":"10.1515/zna-2023-0331","DOIUrl":"https://doi.org/10.1515/zna-2023-0331","url":null,"abstract":"Abstract In this article, a partial differential equation (PDE) model for atherosclerosis disease is presented that analyzes the anti-oxidative activity of high-density lipoprotein (HDL) during the reverse cholesterol transport (RCT) process. The model thoroughly investigates the complex interplay between oxidized low-density lipoprotein (ox-LDL) and high-density lipoprotein in the context of atherosclerosis, emphasizing their combined impact on plaque formation, disease progression, and regression. In addition to this, we considered that monocytes are also attracted by the presence of ox-LDL within the intima. Detailed discussions on stability analyses of the reaction dynamical system at non-inflammatory and chronic equilibrium are provided, followed by a bifurcation analysis for the proposed system. Furthermore, stability analysis for the PDE model in the presence of diffusion is conducted. Our study reveals that the oxidation rate of LDL by monocytes (δ) and the influx rate of HDL (ϕ) due to drugs/diet are primarily responsible for the existence of bi-stability of equilibrium points. In the numerical results, we observe that non-inflammatory or chronic equilibrium points exist for either a short or a long time, and these findings are validated with existing results. The biological elucidation shows the novelty in terms of enhancing our ability to assess intervention efficacy to generate therapeutic strategies resulting in the reduction of the atherosclerotic burden and associated cardiovascular risks.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"52 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139379945","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}
Ahsan Iqbal, A. Rasheed, Areeb Fatima, Sumera Perveen, B. Ramzan, M. Jamil
Abstract Dispersive characteristics of electromagnetic sound waves with frequencies less than the electron and ion gyro-frequencies are studied herein analytically and numerically at astrophysical scales. Magnetic quantization of Fermi states is concerned with the degenerate relativistic electrons fluid treated by quantum hydrodynamic model (QHD). The quantum features are included from Landau quantized Fermi pressure dependent upon the dc magnetic field, whereas the ions are treated as nondegenerate and classical. The numerical analysis verifies the analytical results. The phase speed of magnetosonic waves for relativistic degenerate plasma typically for white dwarf stars parameters is depicted from the graphical figures. In this manuscript, an overlooked feature of quantization, that is Landau quantization, is mainly focused for magnetoacoustics in plasmas.
{"title":"Magnetoacoustics and magnetic quantization of Fermi states in relativistic plasmas","authors":"Ahsan Iqbal, A. Rasheed, Areeb Fatima, Sumera Perveen, B. Ramzan, M. Jamil","doi":"10.1515/zna-2023-0224","DOIUrl":"https://doi.org/10.1515/zna-2023-0224","url":null,"abstract":"Abstract Dispersive characteristics of electromagnetic sound waves with frequencies less than the electron and ion gyro-frequencies are studied herein analytically and numerically at astrophysical scales. Magnetic quantization of Fermi states is concerned with the degenerate relativistic electrons fluid treated by quantum hydrodynamic model (QHD). The quantum features are included from Landau quantized Fermi pressure dependent upon the dc magnetic field, whereas the ions are treated as nondegenerate and classical. The numerical analysis verifies the analytical results. The phase speed of magnetosonic waves for relativistic degenerate plasma typically for white dwarf stars parameters is depicted from the graphical figures. In this manuscript, an overlooked feature of quantization, that is Landau quantization, is mainly focused for magnetoacoustics in plasmas.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"54 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139379902","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}
Mustafa Oguz Nalbant, Süleyman Murat Bağdatli, Ayla Tekin
In this study, vibrations of stepped nanobeams were investigated according to Eringen’s nonlocal elasticity theory. Multi-time scale method, which is one of the perturbation methods, has been applied to solve dimensionless state equations. The solution is considered in two steps. First-order terms obtained from the perturbation expansion formed the linear problem in the first step. In the second step, the solution of the second order of the perturbation expansion was made and nonlinear terms emerged as corrections to the linear problem from this solution. The main issue that the study wants to emphasize is the examination of the mechanical effects of the steps, which are discontinuities encountered at the nanoscale, on the system. For this purpose, while the findings of the research were obtained, various nonlocal parameter values were obtained to capture the nano-scale effect, and frequency-response and nonlinear frequency-amplitude curves corresponding to the 1st Mode values of the beam for different step ratios and step locations were obtained to capture the step effect. One of the important features of the nonlinear system is the formation of internal resonance between the modes of the system. How this situation affects the characteristics of the system has also been examined and results have been given by graphs. The obtained data show that taking into account the nanoscale step is essential for the accuracy and sensitivity of many nanostructures such as sensors, actuators, biostructures, switches, etc. that are likely to be produced at the nanoscale in practice.
{"title":"Three-to-one internal resonances of stepped nanobeam of nonlinearity","authors":"Mustafa Oguz Nalbant, Süleyman Murat Bağdatli, Ayla Tekin","doi":"10.1515/zna-2023-0215","DOIUrl":"https://doi.org/10.1515/zna-2023-0215","url":null,"abstract":"In this study, vibrations of stepped nanobeams were investigated according to Eringen’s nonlocal elasticity theory. Multi-time scale method, which is one of the perturbation methods, has been applied to solve dimensionless state equations. The solution is considered in two steps. First-order terms obtained from the perturbation expansion formed the linear problem in the first step. In the second step, the solution of the second order of the perturbation expansion was made and nonlinear terms emerged as corrections to the linear problem from this solution. The main issue that the study wants to emphasize is the examination of the mechanical effects of the steps, which are discontinuities encountered at the nanoscale, on the system. For this purpose, while the findings of the research were obtained, various nonlocal parameter values were obtained to capture the nano-scale effect, and frequency-response and nonlinear frequency-amplitude curves corresponding to the 1st Mode values of the beam for different step ratios and step locations were obtained to capture the step effect. One of the important features of the nonlinear system is the formation of internal resonance between the modes of the system. How this situation affects the characteristics of the system has also been examined and results have been given by graphs. The obtained data show that taking into account the nanoscale step is essential for the accuracy and sensitivity of many nanostructures such as sensors, actuators, biostructures, switches, etc. that are likely to be produced at the nanoscale in practice.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"66 4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139375496","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}
Extended energy levels and transition data for the Yb LVII are calculated with the GRASP2018 package, which is based on the multiconfiguration Dirac–Hartree–Fock and relativistic configuration methods. Complete and consistent data sets of energy levels, transition rates and lifetimes for electric-dipole (E1), electric-quadrupole (E2), magnetic-dipole (M1), and magnetic-quadrupole (M2) transitions among all these levels are given in this calculation. Three methods of uncertainty estimators are used to evaluate the accuracy of transition data. The computed results are also compared with other theoretical computations. The present results are reported as benchmarks for future calculations and measurements.
{"title":"Extended calculations of energy levels and transition rates for Yb LVII","authors":"Feng Hu, Yan Sun, Maofei Mei, Yufei Lu, Miao Wu, Zhi Feng Yin","doi":"10.1515/zna-2023-0256","DOIUrl":"https://doi.org/10.1515/zna-2023-0256","url":null,"abstract":"Extended energy levels and transition data for the Yb LVII are calculated with the GRASP2018 package, which is based on the multiconfiguration Dirac–Hartree–Fock and relativistic configuration methods. Complete and consistent data sets of energy levels, transition rates and lifetimes for electric-dipole (E1), electric-quadrupole (E2), magnetic-dipole (M1), and magnetic-quadrupole (M2) transitions among all these levels are given in this calculation. Three methods of uncertainty estimators are used to evaluate the accuracy of transition data. The computed results are also compared with other theoretical computations. The present results are reported as benchmarks for future calculations and measurements.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"315 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139092772","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}
Na5Y(WO4)4: 6 % Eu3+, 6 % R+ (R = Li, Na, K) phosphors were synthesized using a high-temperature solid-state reaction method. Through a series of characterization methods, the crystal structure, morphology, composition, and luminescence properties of the sample are obtained. At the same time, the properties of Na5Y(WO4)4: Eu3+ phosphor added with alkali metal ions such as Li+, Na+, K+ were also studied. The experiment showed the red light emission and fluorescence lifetime of Na5Y(WO4)4: 6 % Eu3+ are improved through the doping of low concentration alkali metal agents, and Na5Y(WO4)4: 6 % Eu3+, 6 % Li+ obtained the strongest red light emission intensity. The results indicate that the red emissions intensity of Na5Y(WO4)4: Eu3+ can be enhanced through the Li+ alkali metal agents, which may lead to less use of Y3+ and hence lower cost.
{"title":"Red luminescence properties of Na5Y(WO4)4 doped with Eu3+ and alkali metal ions","authors":"Chenyuan Yuan, Guoying Feng, Qiangshen Chen","doi":"10.1515/zna-2023-0270","DOIUrl":"https://doi.org/10.1515/zna-2023-0270","url":null,"abstract":"Na<jats:sub>5</jats:sub>Y(WO<jats:sub>4</jats:sub>)<jats:sub>4</jats:sub>: 6 % Eu<jats:sup>3+</jats:sup>, 6 % R<jats:sup>+</jats:sup> (R = Li, Na, K) phosphors were synthesized using a high-temperature solid-state reaction method. Through a series of characterization methods, the crystal structure, morphology, composition, and luminescence properties of the sample are obtained. At the same time, the properties of Na<jats:sub>5</jats:sub>Y(WO<jats:sub>4</jats:sub>)<jats:sub>4</jats:sub>: Eu<jats:sup>3+</jats:sup> phosphor added with alkali metal ions such as Li<jats:sup>+</jats:sup>, Na<jats:sup>+</jats:sup>, K<jats:sup>+</jats:sup> were also studied. The experiment showed the red light emission and fluorescence lifetime of Na<jats:sub>5</jats:sub>Y(WO<jats:sub>4</jats:sub>)<jats:sub>4</jats:sub>: 6 % Eu<jats:sup>3+</jats:sup> are improved through the doping of low concentration alkali metal agents, and Na<jats:sub>5</jats:sub>Y(WO<jats:sub>4</jats:sub>)<jats:sub>4</jats:sub>: 6 % Eu<jats:sup>3+</jats:sup>, 6 % Li<jats:sup>+</jats:sup> obtained the strongest red light emission intensity. The results indicate that the red emissions intensity of Na<jats:sub>5</jats:sub>Y(WO<jats:sub>4</jats:sub>)<jats:sub>4</jats:sub>: Eu<jats:sup>3+</jats:sup> can be enhanced through the Li<jats:sup>+</jats:sup> alkali metal agents, which may lead to less use of Y<jats:sup>3+</jats:sup> and hence lower cost.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139096578","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}
Abstract The Newtonian fluid flowing across a semi-infinite plate with variable velocity and pressure is considered in this work. The dimensionless governing equation is obtained by introducing the dimensionless quantities. For infinite region, the artificial boundary approach by using the Laplace transform is applied to gain the absorbing boundary condition (ABC) in a finite region which we call the inner region. The approach differs from the traditional approximation method for infinite boundaries with large values and is first applied to the research. And the stability of the ABC is verified by considering the same point of the outer region and inner region. The numerical difference scheme by using the L1-scheme to approximate the fractional derivative is used to get solutions, and the feasibility assessments, such as stability and convergence, are developed. Three numerical examples are given. In the first example, the exact solution is gained by importing a source term. Through the comparison of numerical solution with exact solution verifies the accuracy of difference method. A comparison between the velocity distribution of the ABC and the infinite boundary approximated by a large value is also discussed and graphically analyzed. In the following two examples, by analyzing the fluid flow over the plate with assorted speeds or pressure gradient, the impact of correlative parameters on the velocity distribution and the flow mechanism are thoroughly analyzed.
{"title":"The absorbing boundary conditions of Newtonian fluid flowing across a semi-infinite plate with different velocities and pressures","authors":"Lin Liu, Jiajia Li, Jingyu Yang, Jihong Wang, Yu Wang, Siyu Chen, Libo Feng, Chiyu Xie, Jing Zhu","doi":"10.1515/zna-2023-0258","DOIUrl":"https://doi.org/10.1515/zna-2023-0258","url":null,"abstract":"Abstract The Newtonian fluid flowing across a semi-infinite plate with variable velocity and pressure is considered in this work. The dimensionless governing equation is obtained by introducing the dimensionless quantities. For infinite region, the artificial boundary approach by using the Laplace transform is applied to gain the absorbing boundary condition (ABC) in a finite region which we call the inner region. The approach differs from the traditional approximation method for infinite boundaries with large values and is first applied to the research. And the stability of the ABC is verified by considering the same point of the outer region and inner region. The numerical difference scheme by using the L1-scheme to approximate the fractional derivative is used to get solutions, and the feasibility assessments, such as stability and convergence, are developed. Three numerical examples are given. In the first example, the exact solution is gained by importing a source term. Through the comparison of numerical solution with exact solution verifies the accuracy of difference method. A comparison between the velocity distribution of the ABC and the infinite boundary approximated by a large value is also discussed and graphically analyzed. In the following two examples, by analyzing the fluid flow over the plate with assorted speeds or pressure gradient, the impact of correlative parameters on the velocity distribution and the flow mechanism are thoroughly analyzed.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"31 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138946905","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}
Chromolaena odorata is an extremely allelopathic and commonly available herb that conquers neighbouring vegetation, and research is being conducted to utilize it for a wide diversity of applications. In the current study, methylene blue dye (MB) is decomposed by exploring the suitability of novel C. odorata for achieving reduced graphene oxide (RGO) through a simplistic green synthesis method. C. odorata assisted RGO is characterized using X-ray diffraction study, scanning electron microscopy, Raman spectroscopy, UV–visible spectrophotometry, photoluminescence spectroscopy and Fourier transform infrared spectroscopy. These characterizations indicate that the synthesized RGO has a UV–visible absorbance peak at 270 nm, an X-ray diffraction reflection peak at 2θ = 2.12°, and a Raman spectrum having an ID/IG ratio of nearly 0.98. Moreover, the RGO sample exhibits excellent MB dye scavenging efficiency having an adsorption amount of 300 mg/g. The adsorption kinetics is also investigated which established that adsorption fits very well with pseudo-second-order kinetics. Furthermore, the thermodynamics behaviour of the RGO sample has been carried out and demonstrated that adsorption is endothermic and spontaneous. The present study offers appropriate visions for the eco-friendly reduction of graphene oxide by C. odorata and utilizing it for the remediation of organic dye.
Chromolaena odorata 是一种极具等位异化作用的常见草本植物，能征服邻近的植被，目前正在进行将其用于多种用途的研究。在目前的研究中，通过一种简单的绿色合成方法，探索新颖的臭铬草对还原型氧化石墨烯（RGO）的适用性，从而分解亚甲基蓝染料（MB）。利用 X 射线衍射研究、扫描电子显微镜、拉曼光谱、紫外可见分光光度法、光致发光光谱和傅立叶变换红外光谱对臭腥草辅助 RGO 进行了表征。这些表征结果表明，合成的 RGO 在 270 纳米处具有紫外可见吸光峰，在 2θ = 2.12°处具有 X 射线衍射反射峰，拉曼光谱的 I D /I G 比值接近 0.98。此外，RGO 样品还具有出色的 MB 染料清除效率，吸附量达到 300 mg/g。对吸附动力学也进行了研究，结果表明吸附非常符合伪二阶动力学。此外，还对 RGO 样品的热力学行为进行了研究，结果表明吸附是内热和自发的。本研究为臭腥草以生态友好的方式还原氧化石墨烯并将其用于有机染料的修复提供了适当的设想。
{"title":"Environmentally friendly reduction of graphene oxide using the plant extract of novel Chromolaena odorata and evaluation of adsorption capacity on methylene blue dye","authors":"Parvathi Edayillam, Dilraj Nidooli, Arjun Ganesh, Akshaya Chalil Veettil, Deepak Nangarath Kannoth","doi":"10.1515/zna-2023-0209","DOIUrl":"https://doi.org/10.1515/zna-2023-0209","url":null,"abstract":"<jats:italic>Chromolaena odorata</jats:italic> is an extremely allelopathic and commonly available herb that conquers neighbouring vegetation, and research is being conducted to utilize it for a wide diversity of applications. In the current study, methylene blue dye (MB) is decomposed by exploring the suitability of novel <jats:italic>C. odorata for achieving reduced</jats:italic> graphene oxide (RGO) through a simplistic green synthesis method. <jats:italic>C. odorata</jats:italic> assisted RGO is characterized using X-ray diffraction study, scanning electron microscopy, Raman spectroscopy, UV–visible spectrophotometry, photoluminescence spectroscopy and Fourier transform infrared spectroscopy. These characterizations indicate that the synthesized RGO has a UV–visible absorbance peak at 270 nm, an X-ray diffraction reflection peak at 2<jats:italic>θ</jats:italic> = 2.12°, and a Raman spectrum having an <jats:italic>I</jats:italic> <jats:sub> <jats:italic>D</jats:italic> </jats:sub>/<jats:italic>I</jats:italic> <jats:sub> <jats:italic>G</jats:italic> </jats:sub> ratio of nearly 0.98. Moreover, the RGO sample exhibits excellent MB dye scavenging efficiency having an adsorption amount of 300 mg/g. The adsorption kinetics is also investigated which established that adsorption fits very well with pseudo-second-order kinetics. Furthermore, the thermodynamics behaviour of the RGO sample has been carried out and demonstrated that adsorption is endothermic and spontaneous. The present study offers appropriate visions for the eco-friendly reduction of graphene oxide by <jats:italic>C. odorata</jats:italic> and utilizing it for the remediation of organic dye.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138823845","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}
Vivek Sharma, Sandeep Kumar, Niti Kant, Vishal Thakur
Laser wakefield acceleration is a frequently utilised research methodology for enhancing the energy levels of lighter charged particles, specifically electrons, to relativistic magnitudes. In this investigation, we utilised a linear polarised Gaussian-like laser pulse that propagated along the z-axis through cold collisionless underdense plasma in weakly nonlinear regime. An external planer magnetic wiggler field is applied along the y-axis. The influence of various critical parameters, such as amplitude and propagation constant of wiggler magnetic field, amplitude of laser electric field and laser pulse length on the wakefield and electron energy gain has been studied. A wiggler-assisted laser wakefield accelerator, the electron energy and wakefield evolution can be tuned by the wiggler magnetic field strength. The numerical findings demonstrate that by varying the strength of wiggler magnetic field and laser electric field, the amplitude of the wakefield is affected significantly. Furthermore, the equality of the order of pulse length and plasma wavelength is essential to obtain energy efficient acceleration mechanism. By employing specific parameters, a maximum energy increase of 2.26 GeV is achieved. This research will aid in the development of an energy-efficient electron acceleration technology by choosing suitable laser and plasma parameters.
激光汪场加速是一种常用的研究方法，可将较轻带电粒子（特别是电子）的能级提升到相对论量级。在这项研究中，我们使用了线性偏振高斯激光脉冲，该脉冲在弱非线性状态下沿 Z 轴穿过冷的无碰撞欠密等离子体。沿 y 轴施加了一个外部平面磁摇摆场。研究了各种关键参数（如摇摆磁场的振幅和传播常数、激光电场的振幅和激光脉冲长度）对唤醒场和电子能量增益的影响。在踌躇器辅助激光唤醒场加速器中，电子能量和唤醒场的演化可通过踌躇器磁场强度进行调节。数值研究结果表明，通过改变摇摆磁场和激光电场的强度，唤醒场的振幅会受到显著影响。此外，脉冲长度和等离子体波长的阶次相等对于获得高效节能的加速机制至关重要。通过采用特定的参数，最大能量增加了 2.26 GeV。通过选择合适的激光和等离子体参数，这项研究将有助于开发高能效的电子加速技术。
{"title":"Effect of wiggler magnetic field on wakefield excitation and electron energy gain in laser wakefield acceleration","authors":"Vivek Sharma, Sandeep Kumar, Niti Kant, Vishal Thakur","doi":"10.1515/zna-2023-0238","DOIUrl":"https://doi.org/10.1515/zna-2023-0238","url":null,"abstract":"Laser wakefield acceleration is a frequently utilised research methodology for enhancing the energy levels of lighter charged particles, specifically electrons, to relativistic magnitudes. In this investigation, we utilised a linear polarised Gaussian-like laser pulse that propagated along the <jats:italic>z</jats:italic>-axis through cold collisionless underdense plasma in weakly nonlinear regime. An external planer magnetic wiggler field is applied along the <jats:italic>y</jats:italic>-axis. The influence of various critical parameters, such as amplitude and propagation constant of wiggler magnetic field, amplitude of laser electric field and laser pulse length on the wakefield and electron energy gain has been studied. A wiggler-assisted laser wakefield accelerator, the electron energy and wakefield evolution can be tuned by the wiggler magnetic field strength. The numerical findings demonstrate that by varying the strength of wiggler magnetic field and laser electric field, the amplitude of the wakefield is affected significantly. Furthermore, the equality of the order of pulse length and plasma wavelength is essential to obtain energy efficient acceleration mechanism. By employing specific parameters, a maximum energy increase of 2.26 GeV is achieved. This research will aid in the development of an energy-efficient electron acceleration technology by choosing suitable laser and plasma parameters.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"79 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138824139","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}
Torkia Ghellab, Zoulikha Charifi, Hakim Baaziz, Nadjia Latelli
The current study focused on examining the structural, mechanical, and optoelectronic properties of CuF, CuCl, CuBr, and CuI by the utilisation of the FP-LAPW method. The calculations reveal that GGA is a better fit than LDA for evaluating structural characteristics, including lattice parameters and bulk modulus. The examination of the band structure reveals that CuF exhibits metallic behaviour, whilst the compounds CuCl, CuBr, and CuI exhibit semiconducting properties, characterised by direct fundamental gaps (Γ → Γ) of 0.516, 0.425, and 1.049 eV, respectively. The peak absorption values for CuCl, CuBr, and CuI are located at 10.68 eV, 9.53 eV, and 7.68 eV, respectively. All materials have ultraviolet absorption peaks. Therefore, the compounds demonstrate substantial absorption in the low- and mid-ultraviolet wavelengths. The four compounds exhibit anisotropic properties, possess ductility, and demonstrate mechanical stability. These entities possess the ability to endure a wide range of temperatures. The thermoelectric performance of the three semiconductors, CuCl, CuBr, and CuI, was investigated. At 300 K, the kL values for CuBr, CuCl, and CuI, are 2.89 W/mK, 3.98 W/mK, and 3.56 W/mK, and the Gruneisen values are as follows: γ (CuCl) = 2.4087, γ (CuBr) = 2.4747, and γ (CuI) = 2.1962. At a temperature of 600 K, the kT value is found to be relatively low. The measured values for the kT of CuCl, CuBr, and CuI are around 1.7818 W m−1 K−1, 1.5109 W m−1 K−1, and 2.8580 W m−1 K−1, respectively. At a temperature of 300 K, the Seebeck coefficients (S) for CuCl, CuBr, and CuI are measured to be 1192.7964 μV/K, 1170.5882 μV/K, and −65.7454 μV/K, respectively. At a temperature of 800 K, the p-type compound CuBr exhibits a maximum figure of merit (ZT) value of 0.6691, corresponding to a charge carrier concentration of 31.7926 × 1020 cm3. The CuCl and CuI compounds exhibit the maximum ZT values of 0.52043 and 0.5609, respectively. In order to achieve the desired results, it is necessary to decrease the charge carrier concentration in CuCl to n = 0.514 × 1022 cm−3 and increase the charge carrier concentration in CuI to n = 9.686 × 1022 cm−3; alternatively, the chemical potentials should be decreased by 0.2563 Ryd and 0.3974 Ryd, respectively.
目前的研究重点是利用 FP-LAPW 方法研究 CuF、CuCl、CuBr 和 CuI 的结构、机械和光电特性。计算结果表明，在评估包括晶格参数和体积模量在内的结构特性时，GGA 比 LDA 的拟合效果更好。对能带结构的研究表明，CuF 具有金属特性，而化合物 CuCl、CuBr 和 CuI 则具有半导体特性，其直接基隙 (Γ → Γ) 分别为 0.516、0.425 和 1.049 eV。CuCl、CuBr 和 CuI 的吸收峰值分别位于 10.68 eV、9.53 eV 和 7.68 eV。所有材料都有紫外线吸收峰。因此，这些化合物在低紫外和中紫外波段有大量吸收。这四种化合物具有各向异性、延展性和机械稳定性。这些实体有能力承受很宽的温度范围。我们对 CuCl、CuBr 和 CuI 这三种半导体的热电性能进行了研究。在 300 K 时，CuBr、CuCl 和 CuI 的 k L 值分别为 2.89 W/mK、3.98 W/mK 和 3.56 W/mK，格鲁尼森值如下：γ（CuCl）= 2.4087，γ（CuBr）= 2.4747，γ（CuI）= 2.1962。在 600 K 的温度下，k T 值相对较低。CuCl、CuBr 和 CuI 的 k T 测量值分别约为 1.7818 W m-1 K-1、1.5109 W m-1 K-1 和 2.8580 W m-1 K-1。在温度为 300 K 时，测得 CuCl、CuBr 和 CuI 的塞贝克系数 (S) 分别为 1192.7964 μV/K、1170.5882 μV/K 和 -65.7454 μV/K。在 800 K 的温度下，p 型化合物 CuBr 的最大优点系数 (ZT) 值为 0.6691，相当于 31.7926 × 1020 cm3 的电荷载流子浓度。CuCl 和 CuI 化合物的最大 ZT 值分别为 0.52043 和 0.5609。为了达到理想的效果，有必要将 CuCl 中的电荷载流子浓度降低到 n = 0.514 × 1022 cm-3，将 CuI 中的电荷载流子浓度提高到 n = 9.686 × 1022 cm-3；或者将化学势分别降低 0.2563 Ryd 和 0.3974 Ryd。
{"title":"Optoelectronics and thermoelectric performances in CuX (X = F, Cl, Br, and I)","authors":"Torkia Ghellab, Zoulikha Charifi, Hakim Baaziz, Nadjia Latelli","doi":"10.1515/zna-2023-0237","DOIUrl":"https://doi.org/10.1515/zna-2023-0237","url":null,"abstract":"The current study focused on examining the structural, mechanical, and optoelectronic properties of CuF, CuCl, CuBr, and CuI by the utilisation of the FP-LAPW method. The calculations reveal that GGA is a better fit than LDA for evaluating structural characteristics, including lattice parameters and bulk modulus. The examination of the band structure reveals that CuF exhibits metallic behaviour, whilst the compounds CuCl, CuBr, and CuI exhibit semiconducting properties, characterised by direct fundamental gaps (Γ → Γ) of 0.516, 0.425, and 1.049 eV, respectively. The peak absorption values for CuCl, CuBr, and CuI are located at 10.68 eV, 9.53 eV, and 7.68 eV, respectively. All materials have ultraviolet absorption peaks. Therefore, the compounds demonstrate substantial absorption in the low- and mid-ultraviolet wavelengths. The four compounds exhibit anisotropic properties, possess ductility, and demonstrate mechanical stability. These entities possess the ability to endure a wide range of temperatures. The thermoelectric performance of the three semiconductors, CuCl, CuBr, and CuI, was investigated. At 300 K, the <jats:italic>k</jats:italic> <jats:sub> <jats:italic>L</jats:italic> </jats:sub> values for CuBr, CuCl, and CuI, are 2.89 W/mK, 3.98 W/mK, and 3.56 W/mK, and the Gruneisen values are as follows: <jats:italic>γ</jats:italic> (CuCl) = 2.4087, <jats:italic>γ</jats:italic> (CuBr) = 2.4747, and <jats:italic>γ</jats:italic> (CuI) = 2.1962. At a temperature of 600 K, the <jats:italic>k</jats:italic> <jats:sub> <jats:italic>T</jats:italic> </jats:sub> value is found to be relatively low. The measured values for the <jats:italic>k</jats:italic> <jats:sub> <jats:italic>T</jats:italic> </jats:sub> of CuCl, CuBr, and CuI are around 1.7818 W m<jats:sup>−1</jats:sup> K<jats:sup>−1</jats:sup>, 1.5109 W m<jats:sup>−1</jats:sup> K<jats:sup>−1</jats:sup>, and 2.8580 W m<jats:sup>−1</jats:sup> K<jats:sup>−1</jats:sup>, respectively. At a temperature of 300 K, the Seebeck coefficients (<jats:italic>S</jats:italic>) for CuCl, CuBr, and CuI are measured to be 1192.7964 μV/K, 1170.5882 μV/K, and −65.7454 μV/K, respectively. At a temperature of 800 K, the <jats:italic>p</jats:italic>-type compound CuBr exhibits a maximum figure of merit (ZT) value of 0.6691, corresponding to a charge carrier concentration of 31.7926 × 10<jats:sup>20</jats:sup> cm<jats:sup>3</jats:sup>. The CuCl and CuI compounds exhibit the maximum ZT values of 0.52043 and 0.5609, respectively. In order to achieve the desired results, it is necessary to decrease the charge carrier concentration in CuCl to <jats:italic>n</jats:italic> = 0.514 × 10<jats:sup>22</jats:sup> cm<jats:sup>−3</jats:sup> and increase the charge carrier concentration in CuI to <jats:italic>n</jats:italic> = 9.686 × 10<jats:sup>22</jats:sup> cm<jats:sup>−3</jats:sup>; alternatively, the chemical potentials should be decreased by 0.2563 Ryd and 0.3974 Ryd, respectively.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"252 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138823814","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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