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排序方式: 共有731条查询结果,搜索用时 46 毫秒
1.
石油炼厂作为用水大户,在水资源逐渐短缺、环境污染日益严重的情况下,实施废水最小化改造具有重要的现实意义。笔者以石油炼厂整个水分配系统年度费用最小为目标函数,提出采用回用、再生回用和再生循环3种措施减少新鲜水用量和废水排放量。利用超结构建模求解所得优化的水分配系统不但要满足各用水过程的需求,而且使排放的废水达标。给出的实例证明,所提出的方法更全面地考虑了废水最小化的机会,且所得结果可行、有效。 相似文献
2.
研究了钛硅铝碳( Ti3Siy-xAlxCz)层间固溶体陶瓷材料的超结构现象。结果发现,用热压Ti、Si、Al和C(石墨)混合粉末原位反应合成的Ti3Si0.9Al0.3C1.93和Ti3Si0.8Al0.4C1.93层间固溶体块体样品的X射线衍射(XRD)谱中[00L]晶面的衍射峰极其微弱,只有[008]面有一个小的衍射峰,[002]、[004]和[006]面几乎没有衍射峰存在,而该块体样品的粉末的X射线衍射谱中所有[00L]晶面的衍射峰均存在。这种超结构现象表明,用热压原位反应合成的Ti3Si0.9Al0.3C1.93和Ti3Si0.8Al0.4C1.93实为层间无序固溶体。由于内应力的释放,取自该块体样品的粉末发生了从无序到有序的转变,所以粉末的X射线衍射谱中显现出强的[00L]面衍射峰。这种超结构相可能对Ti3Si0.9Al0.3C1.93和Ti3Si0.8Al0.4C1.93块体的性能产生重要影响。 相似文献
3.
Kseniia A. Sergeeva Dmitrii V. Pavlov Albert A. Seredin Eugeny V. Mitsai Aleksandr A. Sergeev Evgeny B. Modin Anastasiia V. Sokolova Tsz Chun Lau Kseniia V. Baryshnikova Mihail I. Petrov Stephen V. Kershaw Aleksandr A. Kuchmizhak Kam Sing Wong Andrey L. Rogach 《Advanced functional materials》2023,33(44):2307660
In order to advance the development of quantum emitter-based devices, it is essential to enhance light-matter interactions through coupling between semiconductor quantum dots with high quality factor resonators. Here, efficient tuning of the emission properties of HgTe quantum dots in the infrared spectral region is demonstrated by coupling them to a plasmonic metasurface that supports bound states in the continuum. The plasmonic metasurface, composed of an array of gold nanobumps, is fabricated using single-step direct laser printing, opening up new opportunities for creating exclusive 3D plasmonic nanostructures and advanced photonic devices in the infrared region. A 12-fold enhancement of the photoluminescence in the 900–1700 nm range is observed under optimal coupling conditions. By tuning the geometry of the plasmonic arrays, controllable shaping of the emission spectra is achieved, selectively enhancing specific wavelength ranges across the emission spectrum. The observed enhancement and shaping of the emission are attributed to the Purcell effect, as corroborated by systematic measurements of radiative lifetimes and optical simulations based on the numerical solution of Maxwell's equations. Moreover, coupling of the HgTe photoluminescence to high quality factor modes of the metasurface improves emission directivity, concentrating output within an ≈20° angle. 相似文献
4.
Zhiqiang Wei Zhang‐Kai Zhou Qiuyu Li Jiancai Xue Andrea Di Falco Zhongjian Yang Jianhua Zhou Xuehua Wang 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(27)
Wearable plasmonic devices combine the advantages of high flexibility, ultrathinness, light weight, and excellent integration with the optical benefits mediated by plasmon‐enhanced electric fields. However, two obstacles severely hinder further developments and applications of a wearable plasmonic device. One is the lack of efficient approach to obtaining devices with robust antimotion‐interference property, i.e., the devices can work independently on the morphology changes of their working structures caused by arbitrary wearing conditions. The other issue is to seek a facile and high‐throughput fabrication method to satisfy the financial requirement of industrialization. In order to overcome these two challenges, a functional flexible film of nanowire cluster is developed, which can be easily fabricated by taking the advantages of both conventional electrochemical and sputtering methods. Such flexible plasmonic films can be made into wearable devices that work independently on shape changes induced by various wearing conditions (such as bending, twisting and stretching). Furthermore, due to plasmonic advantages of color controlling and high sensitivity to environment changes, the flexible film of nanowire cluster can be used to fabricate wearable items (such as bracelet, clothes, bag, or even commercial markers), with the ability of wireless visualization for humidity sensing. 相似文献
5.
High Figure of Merit (FOM) of Bragg Modes in Au‐Coated Nanodisk Arrays for Plasmonic Sensing 下载免费PDF全文
Maxime Couture Thibault Brulé Stacey Laing Wenli Cui Mitradeep Sarkar Benjamin Charron Karen Faulds Wei Peng Michael Canva Jean‐Francois Masson 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(38)
Gold‐coated nanodisk arrays of nearly micron periodicity are reported that have high figure of merit (FOM) and sensitivity necessary for plasmonic refractometric sensing, with the added benefit of suitability for surface‐enhanced Raman scattering (SERS), large‐scale microfabrication using standard photolithographic techniques and a simple instrumental setup. Gold nanodisk arrays are covered with a gold layer to excite the Bragg modes (BM), which are the propagative surface plasmons localized by the diffraction from the disk array. This generates surface‐guided modes, localized as standing waves, leading to highly confined fields confirmed by a mapping of the SERS intensity and numerical simulations with 3D finite element method. The optimal gold‐coated nanodisk arrays are applied for refractometric sensing in transmission spectroscopy with better performance than nanohole arrays and they are integrated to a 96‐well plate reader for detection of IgY proteins in the nanometer range in PBS. The potential for sensing in biofluids is assessed with IgG detection in 1:1 diluted urine. The structure exhibits a high FOM of up to 46, exceeding the FOM of structures supporting surface plasmon polaritons and comparable to more complex nanostructures, demonstrating that subwavelength features are not necessary for high‐performance plasmonic sensing. 相似文献
6.
Dominance of Plasmonic Resonant Energy Transfer over Direct Electron Transfer in Substantially Enhanced Water Oxidation Activity of BiVO4 by Shape‐Controlled Au Nanoparticles 下载免费PDF全文
Mi Gyoung Lee Cheon Woo Moon Hoonkee Park Woonbae Sohn Sung Bum Kang Sanghan Lee Kyoung Jin Choi Ho Won Jang 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(37)
The performance of plasmonic Au nanostructure/metal oxide heterointerface shows great promise in enhancing photoactivity, due to its ability to confine light to the small volume inside the semiconductor and modify the interfacial electronic band structure. While the shape control of Au nanoparticles (NPs) is crucial for moderate bandgap semiconductors, because plasmonic resonance by interband excitations overlaps above the absorption edge of semiconductors, its critical role in water splitting is still not fully understood. Here, first, the plasmonic effects of shape‐controlled Au NPs on bismuth vanadate (BiVO4) are studied, and a largely enhanced photoactivity of BiVO4 is reported by introducing the octahedral Au NPs. The octahedral Au NP/BiVO4 achieves 2.4 mA cm?2 at the 1.23 V versus reversible hydrogen electrode, which is the threefold enhancement compared to BiVO4. It is the highest value among the previously reported plasmonic Au NPs/BiVO4. Improved photoactivity is attributed to the localized surface plasmon resonance; direct electron transfer (DET), plasmonic resonant energy transfer (PRET). The PRET can be stressed over DET when considering the moderate bandgap semiconductor. Enhanced water oxidation induced by the shape‐controlled Au NPs is applicable to moderate semiconductors, and shows a systematic study to explore new efficient plasmonic solar water splitting cells. 相似文献
7.
Thermal Scanning at the Cellular Level by an Optically Trapped Upconverting Fluorescent Particle 下载免费PDF全文
8.
9.
Mana Toma Yuji Itakura Shinnosuke Namihara Kotaro Kajikawa 《Advanced Engineering Materials》2023,25(3):2200912
The sensitive direct detection of biomolecules is demonstrated by a colorimetric plasmonic biosensor utilizing the surface colors of plasmonic metasurfaces named Ag nanodome arrays. The Ag nanodome arrays consist of polystyrene bead monolayers coated with Ag thin films whose surface colors are optimized by changing the size of the polystyrene beads. The bulk refractive index sensitivity of colorimetric detection evaluated using the hue angle is 590° RIU−1 (RIU: refractive index unit). For selected geometry, the refractive index resolution (5.0 × 10−5 RIU) obtained by colorimetric detection surpasses that of spectroscopic detection evaluated via the dip wavelength in the reflection spectrum. The numerical simulations predict an enhanced sensing performance when the hue angle of the surface colors of the Ag nanodome arrays changes from 300° to 200°, corresponding to changes in the dip wavelength from 570 to 600 nm in the reflection spectra. Furthermore, the detection sensitivity of the biomolecules is characterized using a direct IgG immunoassay format. The detection limit of the IgG concentration is as low as 134 pM using simple colorimetric detection. The feasibility of sensitive label-free immunoassays using a colorimetric plasmonic biosensor is expected to accelerate the development of highly sensitive and reliable smartphone-based plasmonic biosensors. 相似文献
10.
新型钢-混凝土组合空腹夹层板楼盖具有优异的空间力学特性,适用于大跨度、大柱网的工业与民用建筑,作为一种新的楼盖形式,与普通钢筋混凝土井字楼盖和密肋梁楼盖有较大的区别。以某部队营区篮球馆大跨度楼盖设计为例,介绍其主要设计计算过程。 相似文献