Zeitschrift für Naturforschung A最新文献_第8页

Theoretical determination of speed of sound and fourth virial coefficient by using Kihara (12–6) potential 用Kihara(12-6)势理论确定声速和第四维里系数

Zeitschrift für Naturforschung A Pub Date : 2023-09-04 DOI: 10.1515/zna-2023-0220

E. Somuncu, Bahtiyar A. Mamedov

引用次数: 0

Impact of temperature asymmetry and small fraction of static positive ions on the relaxed states of a relativistic hot pair plasma 温度不对称和少量静态正离子对相对论热对等离子体弛豫态的影响

Zeitschrift für Naturforschung A Pub Date : 2023-08-30 DOI: 10.1515/zna-2023-0112

Usman Shazad, M. Iqbal

{"title":"Impact of temperature asymmetry and small fraction of static positive ions on the relaxed states of a relativistic hot pair plasma","authors":"Usman Shazad, M. Iqbal","doi":"10.1515/zna-2023-0112","DOIUrl":"https://doi.org/10.1515/zna-2023-0112","url":null,"abstract":"Abstract The relaxed state of a magnetized relativistic hot plasma composed of inertial electrons and positrons having different relativistic temperatures and a fraction of static positive ions is studied. From the steady-state solutions of vortex dynamics equations and the relation for current density, a non-force-free triple Beltrami (TB) relaxed state equation is derived. The TB state is characterized by three scale parameters that consequently provide three different self-organized structures. The analysis of the relaxed state shows that for specific values of generalized helicities, the disparity in relativistic temperature and the existence of a small fraction of static positive ions in pair plasma can transform the nature of scale parameters. Moreover, an analytical solution of the TB state for an axisymmetric cylindrical geometry with an internal conductor configuration demonstrates that due to asymmetries of temperature and density of plasma species, diamagnetic structures can transform into paramagnetic ones and vice versa. The present study will improve our understanding of pair plasmas in trap-based plasma confinement experiments and astrophysical environments.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88896667","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}

引用次数: 1

Chaotic dynamics of an extended Duffing-van der Pol system with a non-smooth perturbation and parametric excitation 具有非光滑摄动和参数激励的扩展Duffing-van der Pol系统混沌动力学

Zeitschrift für Naturforschung A Pub Date : 2023-08-28 DOI: 10.1515/zna-2023-0117

Sengen Hu, Liangqiang Zhou

引用次数: 0

Robust white light emission of UV pumped SrCeO3: xSm3+ perovskites for wLEDs 紫外泵浦SrCeO3: xSm3+钙钛矿用于wled的强大白光发射

Zeitschrift für Naturforschung A Pub Date : 2023-08-22 DOI: 10.1515/zna-2023-0145

Shilpa Cherlan Kottianmadathil, Jasira Seere Valappil, Veena Vannadil Puthiyaveetil, Umadevi Peroor, Nissamudeen Kavukuzhi Meerasahib

{"title":"Robust white light emission of UV pumped SrCeO3: xSm3+ perovskites for wLEDs","authors":"Shilpa Cherlan Kottianmadathil, Jasira Seere Valappil, Veena Vannadil Puthiyaveetil, Umadevi Peroor, Nissamudeen Kavukuzhi Meerasahib","doi":"10.1515/zna-2023-0145","DOIUrl":"https://doi.org/10.1515/zna-2023-0145","url":null,"abstract":"Abstract Single phased white light emitting phosphors are more ideal for fabricating white LEDs due to higher stability and color reproducibility. Herein, we report a new white light emitting phosphor, SrCeO3: xSm3+ (x = 1 wt%, 2 wt%, 3 wt%) from a blue light emitting phosphor, SrCeO3 using an efficient, low energy consuming fuel excess gel combustion technique. From the XRD crystallographic investigation, all the synthesised samples have orthorhombic structure with space group Pnma. A broad absorption band in the UV–visible spectra around 350 nm occurs due to the efficient energy transfer from Ce4+ to Sm3+ ion. PL spectra analysis at UV excitations 280 nm and 406 nm, consist of 4f-Sm3+ transitions 4G5/2-6H5/2, 4G5/2-6H7/2, 4G5/2-6H9/2 and charge transfer band from O2− to Ce4+. The energy transfer between activator ions occurs through dipole–dipole interaction, owing to concentration quenching after 2 wt% Sm3+ and the optimised dopant concentration was 2 wt%. SrCe0.98Sm0.02O3 showed mixed blue-yellow-orange-red emission, owing near white light under both excitations. PL data were utilised to find the color parameters and found high color rendering index (CRI ∼ 84) for optimised sample at 406 nm excitation. SEM analysis reveals that the optimised sample exhibit dense ensembled morphology with well-defined grain boundaries and uniformity with average grain size ∼1.24 μm. Further, the elemental composition was confirmed using EDS analysis. From the digital photographs of samples, it is foreseen that, SrCe0.98Sm0.02O3 pumped using near UV LED chip can be used for commercial white light generation.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77558115","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}

引用次数: 0

Bifurcation analysis of ion-acoustic superperiodic waves in ultra-relativistic dense plasma 超相对论致密等离子体中离子声超周期波的分岔分析

Zeitschrift für Naturforschung A Pub Date : 2023-08-11 DOI: 10.1515/zna-2022-0248

S. El-Labany, M. M. Selim, Enas L. Habbak, E. F. El-Shamy

引用次数: 0

Investigation of alkali halide crystals AX (A = Li, Na, K; X = F, Cl, Br) by elastic, mechanical and ultrasonic analysis 碱性卤化物晶体AX (A = Li, Na, K)的研究X = F, Cl, Br)经弹性、力学和超声分析

Zeitschrift für Naturforschung A Pub Date : 2023-08-04 DOI: 10.1515/zna-2023-0138

Anurag Singh, Devraj Singh

引用次数: 0

Effect of deposition potential and saccharin addition on structural, magnetic and magnetoresistance characteristics of NiCoFeCu films 沉积电位和添加糖精对NiCoFeCu薄膜结构、磁性和磁阻特性的影响

Zeitschrift für Naturforschung A Pub Date : 2023-08-03 DOI: 10.1515/zna-2023-0137

Hilal Kuru, Hakan Köçkar, M. Alper

{"title":"Effect of deposition potential and saccharin addition on structural, magnetic and magnetoresistance characteristics of NiCoFeCu films","authors":"Hilal Kuru, Hakan Köçkar, M. Alper","doi":"10.1515/zna-2023-0137","DOIUrl":"https://doi.org/10.1515/zna-2023-0137","url":null,"abstract":"Abstract NiCoFeCu films were electrodeposited on Ti substrates at different deposition potentials and different concentrations of saccharin added to solution. Compositional analysis showed that although Ni was the highest concentration in solution at low potentials of −1.0 V and −1.5 V, the Ni content was lower than the Co content in the films. Anomalous co-deposition behaviour of iron group metals was observed. When the deposition potential increased to −2.0 V and −2.5 V, the Ni content of films increased while the Co, Fe and Cu content decreased. In the case of saccharin addition to the solution, there is a slight change in the film content. All films have face-centred cubic structure. Structural analysis clearly showed that the potential has a significant effect on the texture degree of the films, since the crystal texture changed from (111) to (220) with increasing potential. The surface morphology of the films was observed to be affected by the deposition potential and saccharin concentration. For the magnetic analysis, saturation magnetisation, Ms value gradually decreased from 905 to 715 emu/cm3 with the variation of film content caused by the increase of the potential from −1.0 V to −2.5 V. And, a slight increase in Ms was detected with the addition of saccharin. Besides, the longitudinal and transverse magnetoresistance magnitudes increased from ∼2.5 % to 7.0 % with increasing deposition potential and all films exhibit anisotropic magnetoresistance. Films with desired magnetic properties can be obtained for potential use as magnetic materials in electronics such as magnetoresistive devices.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88828724","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}

引用次数: 0

Structural and optical analysis of nanostructural CuCrO3 perovskite by sol–gel method 溶胶-凝胶法制备纳米结构CuCrO3钙钛矿的结构与光学分析

Zeitschrift für Naturforschung A Pub Date : 2023-07-31 DOI: 10.1515/zna-2023-0108

K. Batool, M. Rani, R. Shafique, R. Neffati, Mariam Akram, M. Arshad

引用次数: 0

Refined composite multivariate multiscale complexity-entropy causality plane analysis for gas-liquid two-phase flow 气液两相流精细复合多元多尺度复杂熵因果平面分析

Zeitschrift für Naturforschung A Pub Date : 2023-07-24 DOI: 10.1515/zna-2023-0115

Xingran Li, Chunling Fan, Jiangfan Qin, Rui Yang

引用次数: 0

Green NiFe2O4 nano-sorbent construction via Foeniculum vulgare extract for efficient barium ions removal 利用小茴香提取物构建绿色NiFe2O4纳米吸附剂，高效去除钡离子

Zeitschrift für Naturforschung A Pub Date : 2023-07-19 DOI: 10.1515/zna-2023-0094

N. Elamin, W. A. El-Fattah, A. Modwi

{"title":"Green NiFe2O4 nano-sorbent construction via Foeniculum vulgare extract for efficient barium ions removal","authors":"N. Elamin, W. A. El-Fattah, A. Modwi","doi":"10.1515/zna-2023-0094","DOIUrl":"https://doi.org/10.1515/zna-2023-0094","url":null,"abstract":"Abstract Ba ions were successfully adsorbed using green NiFe2O4-NPs that were generated using Foeniculum vulgare seeds extract. To investigate the structural and textural characteristics of the adsorbent powder, X-ray diffraction (XRD), nitrogen adsorption–desorption isotherm, X-ray photoelectron spectroscopy (XPS), Fourier transformer infrared (FTIR), and scanning/transmission electron microscopy (SEM) examinations were conducted. The FTIR and EDX investigations revealed the formation of NiFe2O4-NPs as indicated by the elemental composition and the bonding patterns. Some remarkable properties, including the growth of crystallite size and lattice parameters, were reached due to the extract addition, as revealed further by XRD examination. The sorption results were consistent with the Langmuir isotherm model, and the kinetic data were in accordance with pseudo-second-order kinetics. As a result of the electrostatic interaction between the negatively charged NiFe2O4-NPs surface and the positively charged Ba (II) ions, the adsorption process improved significantly above pHzc. The NiFe2O4 nanostructures with high competence for Ba2+ adsorption could be nominated to abolish additional harmful metal cations.","PeriodicalId":23871,"journal":{"name":"Zeitschrift für Naturforschung A","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83102641","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}

引用次数: 1