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排序方式: 共有614条查询结果,搜索用时 15 毫秒
101.
Marcin Runowski Przemysław Woźny Inocencio R. Martín Kevin Soler-Carracedo Teng Zheng Hanoch Hemmerich Fernando Rivera-López Jan Moszczyński Piotr Kulpiński Sascha Feldmann 《Advanced functional materials》2024,34(1):2307791
Nonlinear optical materials are essential in areas such as nanophotonics, optical information processing, and biomedical imaging. However, nanomaterials employed for these diverse applications to date are efficient only for one type of nonlinear optical activity. Herein, the first multimodal nonlinear optically active class of nanomaterials based on lanthanide-doped lithium niobate nanoparticles, which simultaneously exhibit unprecedentedly efficient second and third harmonic generation, as well as up-conversion photoluminescence, is reported. These dielectric nanoparticles retain their high nonlinear optical conversion efficiency both as powder and as aqueous colloidal solution. The high stability also allows for the fabrication of optically active biocompatible micron-sized fibers and polymer-based 3D-printable objects, as well as for fingerprint detection. Finally, the first 8-bit coding platform purely based on multimodal nonlinear optical activity originating from different parametric and nonparametric processes is demonstrated, showcasing the technological potential of these materials for both anti-counterfeiting and advanced optical information processing. 相似文献
102.
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104.
《高等数学》CAI组件的研制 总被引:1,自引:0,他引:1
介绍了研制《高等数学》CAI组件的主导思想、主要内容及其特点,讨论了编程的主要技巧. 相似文献
105.
Synthetic dyes have become an integral part of many industries such as textiles, tannin and even food and pharmaceuticals. Industrial dye effluents from various dye utilizing industries are considered harmful to the environment and human health due to their intense color, toxicity and carcinogenic nature. To mitigate environmental and public health related issues, different techniques of dye remediation have been widely investigated. However, efficient and cost-effective methods of dye removal have not been fully established yet. This paper highlights and presents a review of recent literature on the utilization of the most widely available biopolymers, specifically, cellulose, chitin and chitosan-based products for dye removal. The focus has been limited to the three most widely explored technologies: adsorption, advanced oxidation processes and membrane filtration. Due to their high efficiency in dye removal coupled with environmental benignity, scalability, low cost and non-toxicity, biopolymer-based dye removal technologies have the potential to become sustainable alternatives for the remediation of industrial dye effluents as well as contaminated water bodies. 相似文献
106.
George Dimitrakopoulos Klaus Moessner Clemens Kloeck David Grandblaise Sophie Gault Oriol Sallent Kostas Tsagkaris Panagiotis Demestichas 《Mobile Networks and Applications》2006,11(6):799-811
Users’ expectations towards technology, in terms of quality, service availability and accessibility are ever increasing. Aligned
with this, the wireless world is rapidly moving towards the next generation of systems, featuring cooperating and reconfiguring
capabilities for coexisting (and upcoming) Radio Access Technologies (RATs), so that to improve connectivity and reduce costs.
In this respect, conventional planning and management techniques ought to be replaced by advanced schemes that consider multidimensional
characteristics, increased complexity and high speeds. To this effect, means are needed capable to support scalability and
to cater for advanced service features, provided to users at high rates and cost-effectively. This article provides a scheme
to optimize resource management in future systems, by describing a platform that accommodates engineering mechanisms that
deal with dynamic, demand driven planning and managing of spectrum and radio resources in reconfigurable networks. To do so,
it first discusses the fundamentals and the approach followed in the proposed architecture and then investigates the basic
functional modules. The architecture is validated through a set of use-cases that exemplify the operational applicability
and efficiency in a wide range of communication scenarios.
相似文献
Panagiotis DemestichasEmail: |
107.
针对专用集成电路(ASIC)设计中功能验证的效率和完备性问题,以验证方法学手册(VMM)为基础搭建了串行高级技术附件(SATA)控制器分层式验证平台.验证组件的实现大量重用验证知识产权核(VIP),在采用随机激励的基础上以覆盖率统计驱动验证的过程,根据SATA控制器的功能设计记分牌进行结果的自动化比对.实验结果表明,这些方法提高了功能验证的效率,保证了验证的完备性,最终功能覆盖率达到98.25%. 相似文献
108.
Qaiser Rafiq Muhammad Tahir Khan Sikander Azam Amin ur Rahman Sardar Sikandar Hayat Yousef Mohammed Alanazi Syed Sheraz Ahmad 《International journal of quantum chemistry》2024,124(2):e27335
This study aimed to comprehensively investigate the optoelectronic and magnetic properties of Mo, Zn/LiNbO3 (1 1 1) material. The primary objectives were to understand the potential for manipulating the material's magnetism and to elucidate the origin of spin-polarized states and magnetic moments, particularly with respect to the unpaired d orbitals of Nb, Mo, and Zn atoms. To achieve these objectives, we employed the Pardew–Burke–Ernzerhof (PBE) method within the Generalized Gradient Approximation (GGA + U) framework. This computational approach allowed us to examine the optoelectronic and magnetic characteristics of the material in detail. Our research yielded several key findings that enhance our understanding of Mo, Zn/LiNbO3 (1 1 1) material. We observed a modest improvement in the material's absorption capacity within the visible spectrum, accompanied by a discernible red-shift. Notably, our study involved the calculation of the dielectric function and refractive constant of the material, revealing a strong correlation between absorption trends and the dielectric constant. Furthermore, our investigation uncovered that Mo, Zn/LiNbO3 (1 1 1) exhibits distinct conduction and valence bands, with p and d orbitals predominantly contributing to each, respectively. The energy gap of the material falls within a range of 0.30–1.04 eV. A particularly significant finding was the narrower band gap of Mo, Zn/LiNbO3 (1 1 1) material, which can be attributed to the superposition of Mo-d and Zn-p orbit energy levels with O-p orbit energy levels, ultimately forming a covalent bond. Importantly, our research demonstrated the material's heightened optical absorption within the visible spectrum, suggesting its suitability for various photonic and optoelectronic applications. Additionally, we calculated a wide range of optical characteristics, including the dielectric function, absorption coefficient, energy loss, reflectivity, refractive index, extinction coefficient, and optical conductivity, providing a comprehensive assessment of the material's optical properties. 相似文献
109.
进阶持续性渗透攻击的特征分析研究 总被引:1,自引:0,他引:1
进阶持续性渗透攻击是一类针对特定组织或者目标的一系列攻击行为的总称。这种攻击具有渗透行动上的复杂性和攻击手段上的多元性。通过对于进阶持续性渗透攻击的流程分析发现:进阶持续性渗透攻击在发展过程中具有长期性和阶段性,其中攻击行为在静态和变化态中交替转换;另一方面,进阶持续性渗透的一系列攻击在使用攻击方法上同时使用现有的多种手段,具有非单一性和间接性,使得受害方难以发现并且单一防范工作难以奏效。 相似文献
110.
随着高新技术的不断涌现,电磁环境日益复杂,雷达面临的挑战愈加严重,如何提高雷达在复杂电磁环境中的生存能力,是影响现代战争胜败的重要因素。雷达若要在日益复杂的电磁环境中发挥作用,必须注重概念和体制的创新,其理论和技术也必须不断有所突破和发展,才能适应现代战争的需要。本文介绍雷达的新概念、新技术以及能在复杂电磁环境中正常工... 相似文献