检索结果-内蒙古大学图书馆

arXiv 2022年

作者： Baer, Andreas Malgaretti, Paolo Kaspereit, Malte Harting, Jens Smith, Ana-Sunčana Cauerstr. 3 Erlangen91058 Germany Forschungszentrum Jülich Cauerstr. 1 Erlangen91058 Germany Friedrich-Alexander-Universität Erlangen-Nürnberg Department of Chemical and Biological Engineering Institute for Separation Science & Technology Egerlandstrasse 3 Erlangen91058 Germany Friedrich-Alexander-Universität Erlangen-Nürnberg Department of Chemical and Biological Engineering Department of Physics Cauerstr. 1 Erlangen91058 Germany Group of Computational Life Sciences Department of Physical Chemistry Ruder Bošković Institute Bijenička 54 Zagreb10000 Croatia

Accurate modeling of diffusive transport of nanoparticles across nanopores is a particularly challenging problem. The reason is that for such narrow pores the large surface-to-volume ratio amplifies the relevance of the nanoscopic details and of the effective interactions at the interface with pore walls. Close to the pore wall, there is no clear separation between the length scales associated with molecular interactions, layering of the solvent at the interface with the pore and the particle size. Therefore, the standard hydrodynamic arguments may not apply and alternative solutions to determining average transport coefficients need to be developed. We here address this problem by offering a multiscale ansatz that uses effective potentials determined from molecular dynamics simulations to parametrise a four state stochastic model for the positional configuration of the particle in the pore. This is in turn combined with diffusivities in the centre of the pore and at the pore wall to calculate the average diffusion constant. We apply this model to the diffusion of fullerenes in a toluene filled slit nanopore and calculate the mean diffusion coefficient as a function of the pore size. We show that the accuracy of our model is affected by the partial slip of the toluene on the pore wall. © 2022, CC BY.

关键词： Diffusion

来源：评论

学校读者我要写书评

暂无评论

Elettaria cardamomum seed extract synthesized silver nanoparticles for efficient catalytic reduction of toxic dyes

引用

Environmental Nanotechnology, Monitoring and Management 2023年 20卷

作者： Zahid, Muhammad Segar, Abdul Sattar M. Al-Majmaie, Shaymaa Shather, A.H. Khan, Muhammad Farooq Alguno, Arnold C. Capangpangan, Rey Y. Ismail, Ahmed Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China Heilongjiang University Harbin 150080 China Al-Farahidi University College of Dentistry Baghdad 10022 Iraq Department of Biotechnology College of Science University of Diyala Iraq Department of Computer Engineering Technology Al Kitab University Altun Kopru Kirkuk 00964 Iraq Institute of Chemical Sciences University of Peshawar Peshawar 25120 Pakistan Department of Physics and Premier Research Institute of Science and Mathematics (PRISM) Mindanao State University-iligan Institute of Technology Tibanga Highway Ilign City 9200 Philippines Department of Physical Sciences and Mathematics College of Marine and Allied Sciences Mindanao State University at Naawan Naawan 9023 Misamis Oriental Philippines

The emissions of lethal organic pollutants, e.g., toxic dyes, from various industries result in the contamination of water, and hence, it is highly desirable to eradicate these pollutants. Herein, the catalytic reduction of hazardous methylene blue (MB) and rhodamine B (RhB) dyes has been evaluated (using sodium borohydride (NaBH₄) as a reductant) by silver nanoparticles prepared from an extract of Elettaria cardamomum seeds (EC-Ag NPs). The UV–visible spectroscopy confirmed the successful formation of EC-Ag NPs. The results from the transmission electron microscopic (TEM) study indicated the spherical shape with an average particle size of 5.4 nm, along with the crystalline nature of EC-Ag NPs revealed from the XRD study. What is more, the FTIR result verified the existence of phytoconstituents that act as both stabilizing and reducing agents. The as-synthesized ES-Ag NPs showed excellent activity in the catalytic reduction of both lethal dyes (MB and RhB) in the presence of NaBH₄. The reduction results revealed that it takes 7 and 10 min, respectively, to completely eradicate the MB and RhB, with rate constants of 0.328 and 0.244 min⁻¹, which are significantly better than those previously reported. In addition, the as-synthesized ES-Ag NPs exhibit outstanding stability up to several rounds during the reduction of both dyes, proving their practical applicability at industrial and domestic levels. © 2023 Elsevier B.V.

关键词： Catalytic reduction Elettaria Cardamomum Green synthesis Silver nanoparticles Toxic dyes

来源：评论

学校读者我要写书评

暂无评论

High-resolution spectroscopy of neutral Yb atoms in a solid Ne matrix

引用

physical Review A 2021年第6期104卷 062809-062809页

作者： R. Lambo C.-Y. Xu (徐晨昱) S. T. Pratt H. Xu (徐红) J. C. Zappala K. G. Bailey Z.-T. Lu (卢征天) P. Mueller T. P. O'Connor B. B. Kamorzin D. S. Bezrukov Y.-Q. Xie (谢耀钦) A. A. Buchachenko J. T. Singh Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 China Physics Division Argonne National Laboratory Argonne Illinois 60439 USA Department of Physics and Enrico Fermi Institute University of Chicago Chicago Illinois 60637 USA Chemical Science and Engineering Division Argonne National Laboratory Lemont Illinois 60439 USA Hefei National Laboratory for Physical Sciences at the Microscale CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China 96 Jinzhai Road Hefei 230026 China CEST Skolkovo Institute of Science and Technology Skolkovo Innovation Center Moscow 121205 Russia Department of Chemistry M.V. Lomonosov Moscow State University Moscow 119991 Russia National Superconducting Cyclotron Laboratory Michigan State University East Lansing Michigan 48824 USA

We present an experimental and theoretical study of the absorption and emission spectra of Yb atoms in a solid Ne matrix at a resolution of 0.025 nm. Five absorption bands were identified as due to transitions from the 4f145d06s21S0 ground-state configuration to 4f145d06s6p and 4f135d16s2 configurations. The two lowest-energy bands were assigned to outer-shell transitions to 6s6p3P1 and 1P1 atomic states and displayed the structure of a broad doublet and an asymmetric triplet, respectively. The remaining three higher-frequency bands were assigned to inner-shell transitions to distinct J=1 states arising from the 4f135d16s2 configuration and were highly structured with narrow linewidths. A classical simulation was performed to identify the stability and symmetry of possible trapping sites in the Ne crystal. It showed that the overarching 1+2 structure of the high-frequency bands could be predominantly ascribed to crystal-field splitting in the axial field of a 10-atom vacancy of C4v symmetry. Their prominent substructures were shown to be manifestations of phonon sidebands associated with the zero-phonon lines on each crystal-field state. Unprecedented for a metal–rare-gas system, resolution of individual phonon states on an allowed electronic transition was possible under excitation spectroscopy which reflects the semiquantum nature of solid Ne. In contrast to the absorption spectra, emission spectra produced by steady-state excitation into the 1P1 absorption band consisted of simple, unstructured fluorescence bands.

关键词： Atomic spectra Electronic structure of atoms & molecules Jahn-Teller effect Van der Waals interaction

来源：评论

学校读者我要写书评

暂无评论

Sn-doped g-C3N4 as a novel photoelectrocatalyst for water oxidation

引用

Journal of physics and Chemistry of Solids 2023年 176卷

作者： Aboubakr, Ahmed Esmail A. Khan, Malik Dilshad Revaprasadu, Neerish Millet, Pierre Hung, Chen-Hsiung El Rouby, Waleed M.A. Sustainable Chemical Science and Technology Taiwan International Graduate Program Taiwan Department of Applied Chemistry National Yang Ming Chiao Tung University Hsinchu30010 Taiwan Institute of Chemistry Academia Sinica 128 Sec 2 Academia Rd Nankang Taipei11529 Taiwan Beni-Suef University Beni-Suef62511 Egypt Department of Chemistry University of Zululand Private Bag X1001 Kwadlangezwa3886 South Africa Institute of Physical Chemistry Polish Academy of Sciences Kasprzaka 44/52 Warsaw01-224 Poland Paris-Saclay University ICMMO-Eri'ee UMR CNRS 8182 Orsay 91405 France

The photocatalytic performance of graphitic carbon nitride can be enhanced multifold by introducing suitable dopants. Here we report incorporating a cost-effective, non-toxic and abundant element, i.e., tin, in elongated semiconducting carbon nitride (g-C3N4). A novel procedure was used to introduce varying amounts of tin to the g-C3N4 framework. The new photocatalysts (Sn–CN) were characterized by X-Ray Diffraction (XRD) and FT-IR measurements, confirming the absence of tin oxide and incorporation of tin in the g-C3N4 backbone. The SEM, EDX, TEM and XPS measurements demonstrated the elongated morphology and the presence of tin in the composite materials. BET measurements showed a relative increase in the specific surface area for the composites. The optical measurements showed enhanced solar light absorption and promoted the charge carrier's separation after the insertion of Sn to g-C3N4. Photoelectrochemical water dissociation measurements showed that 10% tin doping increased the activity of g-C3N4 to water photo-oxidation about four times. This improvement was analyzed by electrochemical impedance spectroscopy measurements. © 2023 Elsevier Ltd

关键词： Morphology

来源：评论

学校读者我要写书评

暂无评论

Interplay between Charge-Density-Wave, Superconductivity, and Ferromagnetism in CuIr2-xCrxTe4Chalcogenides

arXiv

引用

arXiv 2022年

作者： Zeng, Lingyong Hu, Xunwu Wang, Ningning Sun, Jianping Yang, Pengtao Boubeche, Mebrouka Luo, Shaojuan He, Yiyi Cheng, Jinguang Yao, Dao-Xin Luo, Huixia School of Materials Science and Engineering State Key Laboratory of Optoelectronic Materials and Technologies Key Lab of Polymer Composite & Functional Materials Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices Sun Yat-Sen University No. 135 Xingang Xi Road Guangzhou510275 China School of Physics Center for Neutron Science and Technology State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-Sen University Guangzhou510275 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences Beijing100190 China School of Chemical Engineering and Light Industry Guangdong University of Technology Guangzhou510006 China

We report the crystal structure, charge-density-wave (CDW), superconductivity (SC), and ferromagnetism (FM) in CuIr2-xCrxTe4(0 ≤ x ≤ 2) chalcogenides. Powder x-ray diffraction (PXRD) results reveal that CuIr2-xCrxTe4series are distinguished between two structural types and three different regions: (i) layered trigonal structure region, (ii) mixed phase regions, (iii) spinel structure region. Besides, Cr substitution for Ir site results in rich physical properties including the collapse of CDW, the formation of dome-shaped like SC, and the emergence of magnetism. Cr doping slightly elevates the superconducting critical temperature (Tsc) to its highest Tsc= 2.9 K around x = 0.06. As x increases from 0.3 to 0.4, the ferromagnetic Curie temperature (Tc) increases from 175 to 260 K. However, the Tcremains unchanged in the spinel range of 1.9 ≤ x ≤ 2. This finding provides a comprehensive material platform for investigating the interplay between CDW, SC, and FM multipartite quantum states. Copyright © 2022, The Authors. All rights reserved.

关键词： Ferromagnetism

来源：评论

学校读者我要写书评

暂无评论

Few-qubit quantum refrigerator for cooling a multi-qubit system

arXiv

引用

arXiv 2020年

作者： Arısoy, Onat Müstecaplıoğlu, Özgür E. Institute for Physical Science and Technology University of Maryland College ParkMD20742 United States Chemical Physics Program University of Maryland College ParkMD20742 United States Department of Physics Koç University Sarıyer İstanbul34450 Turkey

We propose to use a few-qubit system as a compact quantum refrigerator for cooling an interacting multi-qubit system. We specifically consider a central qubit coupled to N ancilla qubits in a so-called spin-star model as our quantum refrigerator. We first show that if the interaction between the qubits is of the longitudinal and ferromagnetic Ising model form, the central qubit is colder than the environment. The colder central qubit is then proposed to be used as the refrigerant interface of the quantum refrigerator to cool down general quantum many-qubit systems. We discuss a simple refrigeration cycle, considering the operation cost and cooling efficiency, which can be controlled by N and the qubit-qubit interaction strength. Besides, bounds on the achievable temperature are established. Such few-qubit compact quantum refrigerators can be significant to reduce dimensions of quantum technology applications, can be easy to integrate into all-qubit systems, and can increase the speed and power of quantum computing and thermal devices. Copyright © 2020, The Authors. All rights reserved.

关键词： Refrigerators

来源：评论

学校读者我要写书评

暂无评论

Coexistence of ferromagnetism, antiferromagnetism, and superconductivity in magnetically anisotropic (Eu,La)FeAs2

arXiv

引用

arXiv 2021年

作者： Yu, Jia Le, Congcong Li, Zhiwei Li, Lisi Liu, Tong Liu, Zengjia Zhang, Bo Shen, Bing Ruan, Binbin Ren, Zhi'An Wang, Meng Center for Neutron Science and Technology School of Physics Sun Yat-sen University Guangzhou510275 China Max Planck Institute for Chemical Physics of Solids Dresden01187 Germany Key Lab for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou University Lanzhou730000 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing100049 China

Materials with exceptional magnetism and superconductivity usually conceive emergent physical phenomena. Here, we investigate the physical properties of the (Eu,La)FeAs2system with double magnetic sublattices. The parent EuFeAs2shows anisotropy-associated magnetic behaviors, such as Eu-related moment canting and exchange bias. Through La doping, the magnetic anisotropy is enhanced with ferromagnetism of Eu2+realized in the overdoped region, and a special exchange bias of the superposed ferromagnetic/superconducting loop revealed in Eu0.8La0.2FeAs2. Meanwhile, the Fe-related antiferromagnetism shows unusual robustness against La doping. Theoretical calculation and 57Fe Mössbauer spectroscopy investigation reveal a doping-tunable dual itinerant/localized nature of the Fe-related antiferromagnetism. Coexistence of the Eu-related ferromagnetism, Fe-related robust antiferromagnetism, and superconductivity is further revealed in Eu0.8La0.2FeAs2, providing a platform for further exploration of potential applications and emergent physics. Finally, an electronic phase diagram is established for (Eu,La)FeAs2with the whole superconducting dome adjacent to the Fe-related antiferromagnetic phase, which is of benefit for seeking underlying clues to high-temperature superconductivity. Copyright © 2021, The Authors. All rights reserved.

关键词： Antiferromagnetism

来源：评论

学校读者我要写书评

暂无评论

Selection rules and dynamic magnetoelectric effect of the spin waves in multiferroic BiFeO3

引用

physical Review B 2021年第17期104卷 174429-174429页

作者： D. G. Farkas D. Szaller I. Kézsmárki U. Nagel T. Rõõm L. Peedu J. Viirok J. S. White R. Cubitt T. Ito R. S. Fishman S. Bordács Department of Physics Budapest University of Technology and Economics 1111 Budapest Hungary MTA-BME Condensed Matter Research Group 1111 Budapest Hungary Institute of Solid State Physics TU Wien 1040 Vienna Austria Experimental Physics V Center for Electronic Correlations and Magnetism Institute of Physics University of Augsburg 86159 Augsburg Germany National Institute of Chemical Physics and Biophysics Akadeemia tee 23 12618 Tallinn Estonia Laboratory for Neutron Scattering and Imaging (LNS) Paul Scherrer Institut (PSI) CH-5232 Villigen Switzerland Institut Laue-Langevin 71 avenue des Martyrs CS 20156 38042 Grenoble Cedex 9 France National Institute of Advanced Industrial Science and Technology (AIST) Tsukuba 305-8562 Ibaraki Japan Materials Science and Technology Division Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA Hungarian Academy of Sciences Premium Postdoctor Program 1051 Budapest Hungary

We report the magnetic-field dependence of the THz absorption and nonreciprocal directional dichroism spectra of BiFeO3 measured on the three principal crystal cuts for fields applied along the three principal directions of each cut. From the systematic study of the light polarization dependence, we deduced the optical selection rules of the spin-wave excitations. Our THz data, combined with small-angle neutron scattering results showed that (i) an in-plane magnetic field rotates the q vectors of the cycloids perpendicular to the magnetic field and (ii) the selection rules are mostly determined by the orientation of the q vector with respect to the electromagnetic fields. We observed a magnetic field history-dependent change in the strength and the frequency of the spin-wave modes, which we attributed to the change of the orientation and the length of the cycloidal q vector, respectively. Finally, we compared our experimental data with the results of linear spin-wave theory that reproduces the magnetic-field dependence of the spin-wave frequencies and most of the selection rules, from which we identified the spin-polarization coupling terms relevant for the optical magnetoelectric effect.

关键词： Magnetoelectric effect Spin waves Multiferroics Small angle neutron scattering Terahertz spectroscopy

来源：评论

学校读者我要写书评

暂无评论

Robust weyl semimetal and pressure-induced superconductivity in quasi-one-dimensional (nbse4)2i

arXiv

引用

arXiv 2021年

作者： Pei, Cuiying Shi, Wujun Zhao, Yi Gao, Lingling Gao, Jiacheng Li, Yiwei Zhu, Haiyin Zhang, Qing Yu, Na Li, Changhua Cao, Weizheng Medvedev, Sergey A. Felser, Claudia Yan, Binghai Liu, Zhongkai Chen, Yulin Wang, Zhijun Qi, Yanpeng School of Physical Science and Technology ShanghaiTech University Shanghai201210 China Center for Transformative Science ShanghaiTech University Shanghai201210 China ShanghaiTech University Shanghai201210 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing100190 China University of Chinese Academy of Sciences Beijing100049 China Department of Physics Clarendon Laboratory University of Oxford Parks Road OxfordOX1 3PU United Kingdom Max Planck Institute for Chemical Physics of Solids Dresden01187 Germany Department of Condensed Matter Physics Weizmann Institute of Science Rehovot7610001 Israel

A search for the single material system that simultaneously exhibits topological phase and intrinsic superconductivity has been largely limited, although such a system is far more favorable especially for the quantum device applications. Except artificially engineered topological superconductivity in heterostructure systems, another alternative is to have superconductivity arising from the topological materials by pressure or other "clean" technology. Here, based on first-principles calculations, we first show that quasi-one-dimensional compound (NbSe4)2I represents a rare example of a chiral Weyl semimetal in which the set of symmetry-related Weyl points (WPs) exhibit the same chiral charge at a certain energy. The net chiral charge (NCC) of the below Fermi level EF (or a certain energy) can be tuned by pressure. In addition, a partial disorder induced by pressure accompanied with superconductivity emerges. Although amorphization of the iodine sub-lattice under high pressure, the one-dimensional NbSe4 chains in (NbSe4)2I remain intact and provide a superconducting channel in one dimension. Our combined theoretical and experimental research provide critical insight into a new phase of the one-dimensional system, in which distinctive phase transitions and correlated topological states emerge upon compression. © 2021, CC BY-NC-ND.

关键词： Selenium compounds

来源：评论

学校读者我要写书评

暂无评论

Electron-electron interactions in low-dimensional Si:P delta layers

引用

physical Review B 2020年第24期101卷 245419-245419页

作者： Joseph A. Hagmann Xiqiao Wang Ranjit Kashid Pradeep Namboodiri Jonathan Wyrick Scott W. Schmucker M. D. Stewart, Jr. Richard M. Silver Curt A. Richter Physical Measurement Laboratory National Institute for Standards and Technology 100 Bureau Dr. Gaithersburg Maryland 20899 USA Chemical Physics Program University of Maryland College Park Maryland 20742 USA Joint Quantum Institute University of Maryland College Park Maryland 20742 USA

Scientists have long studied the physics of highly disordered conducting systems, seeking to understand the multitude of quantum phenomena that govern how electrons move through material systems. Recently, research into silicon-based quantum computing has made disordered conducting systems, such as Si:P monolayers embedded in isotopically pure Si, technically relevant. Consequently, applying and advancing the theoretical frameworks developed to describe electron behavior in disordered systems is a necessary objective in this field of research. This study investigates key components of dopant-based Si quantum computing devices: embedded regions of highly doped delta layers (δ layers). We examine the transport behavior and the electron-electron interaction (EEI) physics in embedded Si:P δ layers by means of self-consistent magnetotransport measurements. Parameters associated with the electronic transport offer a meaningful quantitative characterization of δ-layer quality and dopant diffusion. In addition, by examining EEI behaviors in a set of samples with embedded Si:P δ layers produced with different PH3 exposure procedures prior to Si encapsulation, we show how details of material synthesis affect the dimensionality of charge carrier interactions in embedded Si:P δ layers. The relationship between δ-layer confinement and EEI screening lengths is established here. This understanding will help validate important models used for device simulation and design and lead to improvements in the control of electrostatic gating of and tunneling transport through Si:P single atom transistors.

关键词： Dopants Quantum interference effects Transport phenomena Weak localization Doped semiconductors Two-dimensional electron system Drude model Hall bar Molecular beam epitaxy Secondary ion mass spectrometry

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：