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High-efficiency sodium storage of Co_(0.85)Se/WSe_(2) encapsulated in N-doped carbon polyhedron via vacancy and heterojunction engineering 被引量:2
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作者 Ya Ru Pei Hong Yu Zhou +5 位作者 Ming Zhao Jian Chen Li Xin Ge Wei Zhang Chun Cheng Yang Qing Jiang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期94-107,共14页
With the advantage of fast charge transfer,heterojunction engineering is identified as a viable method to reinforce the anodes'sodium storage performance.Also,vacancies can effectively strengthen the Na+adsorption... With the advantage of fast charge transfer,heterojunction engineering is identified as a viable method to reinforce the anodes'sodium storage performance.Also,vacancies can effectively strengthen the Na+adsorption ability and provide extra active sites for Na+adsorption.However,their synchronous engineering is rarely reported.Herein,a hybrid of Co_(0.85)Se/WSe_(2) heterostructure with Se vacancies and N-doped carbon polyhedron(CoWSe/NCP)has been fabricated for the first time via a hydrothermal and subsequent selenization strategy.Spherical aberration-corrected transmission electron microscopy confirms the phase interface of the Co_(0.85)Se/WSe_(2) heterostructure and the existence of Se vacancies.Density functional theory simulations reveal the accelerated charge transfer and enhanced Na+adsorption ability,which are contributed by the Co_(0.85)Se/WSe_(2) heterostructure and Se vacancies,respectively.As expected,the CoWSe/NCP anode in sodium-ion battery achieves outstanding rate capability(339.6 mAh g^(−1) at 20 A g^(−1)),outperforming almost all Co/W-based selenides. 展开更多
关键词 Co_(0.85)Se/WSe_(2)heterostructure density functional theory simulations N-doped carbon polyhedron Se vacancies sodium-ion batteries
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Facile synthesis of the Mn_(3)O_(4)polyhedron grown on N-doped honeycomb carbon as high-performance negative material for lithium-ion batteries 被引量:1
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作者 Dan Zhang Chunyan Zhang +7 位作者 Xuan Zheng Yizhuo Zhao Xinyu Shi Baomin Luo Yuzhu Li Guangyin Liu Xiaodi Liu Chuang Yu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第6期1152-1161,共10页
Because of their large volume variation and inferior electrical conductivity,Mn_(3)O_(4)-based oxide anode materials have short cyclic lives and poor rate capability,which obstructs their development.In this study,we ... Because of their large volume variation and inferior electrical conductivity,Mn_(3)O_(4)-based oxide anode materials have short cyclic lives and poor rate capability,which obstructs their development.In this study,we successfully prepared a Mn_(3)O_(4)/N-doped honeycomb carbon composite using a smart and facile synthetic method.The Mn_(3)O_(4)nanopolyhedra are grown on N-doped honeycomb carbon,which evidently mitigates the volume change in the charging and discharging processes but also improves the electrochemical reaction kinetics.More importantly,the Mn-O-C bond in the Mn_(3)O_(4)/N-doped honeycomb carbon composite benefits electrochemical reversibility.These features of the Mn_(3)O_(4)/N-doped honeycomb carbon(NHC)composite are responsible for its superior electrochemical performance.When used for Li-ion batteries,the Mn_(3)O_(4)/N-doped honeycomb carbon anode exhibits a high reversible capacity of 598 mAh·g^(−1)after 350 cycles at 1 A·g^(−1).Even at 2 A·g^(−1),the Mn_(3)O_(4)/NHC anode still delivers a high capacity of 472 mAh·g^(−1).This work provides a new prospect for synthesizing and developing manganese-based oxide materials for energy storage. 展开更多
关键词 Mn_(3)O_(4) polyhedron nitrogen-doped honeycomb carbon anode lithium-ion battery
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Unique NiFe–NiCoO2 hollow polyhedron as bifunctional electrocatalysts for water splitting 被引量:2
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作者 Rong Shi Jiaxin Wang +2 位作者 Zhi Wang Tengfei Li Yu-Fei Song 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第6期74-80,共7页
It is of significance to design of stable and cost-effective electrocatalyst for water splitting with high efficiency in an alkaline medium.The major obstacles for practical application of water splitting devices are ... It is of significance to design of stable and cost-effective electrocatalyst for water splitting with high efficiency in an alkaline medium.The major obstacles for practical application of water splitting devices are lack of high-efficiency and low-cost electrocatalysts with low overpotential for both HER and OER.In this paper,we report a NiFe alloy decorated NiCoO2 hollow polyhedron(denoted as Ni Fe–Ni Co O2)by using[NiFe(CN)6]- intercalated NiCo–LDH as precursor.As evidenced by the electrochemical active surface area,the resultant Ni Fe–Ni Co O2 composite shows unique hollow nanostructure,which can not only provide abundant mass transport channels,but also increase the contact area of the NiFe–Ni Co O2 material with the electrolyte.The overpotential(η)demand is 286 mV for OER and 102 mV for HER at the current density of 10 mA/cm2 in an alkaline medium of 1 M KOH for the NiFe/NiCoO2 composite.This work provides a new pathway for preparation of the highly efficient bifunctional electrocatalysts for water splitting. 展开更多
关键词 Layered double HYDROXIDES (LDHs) HOLLOW polyhedron Water splitting
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Ratio of In-Sphere Volume to Polyhedron Volume of the Great Pyramid Compared to Selected Convex Polyhedral Solids 被引量:4
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作者 Hans Hermann Otto 《Journal of Applied Mathematics and Physics》 2021年第1期41-56,共16页
The architecture of the Great Pyramid at Giza is based on fascinating golden mean geometry. Recently the ratio of the in-sphere volume to the pyramid volume was calculated. One yields as result <em>R</em>&... The architecture of the Great Pyramid at Giza is based on fascinating golden mean geometry. Recently the ratio of the in-sphere volume to the pyramid volume was calculated. One yields as result <em>R</em><sub><em>V</em></sub> = π <span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8901;</span></span> <em><em style="white-space:normal;">φ</em></em><sup>5</sup>, where <img src="Edit_83decbce-7252-44ed-a822-fef13e43fd2a.bmp" alt="" /> is the golden mean. It is important that the number <em>φ</em><sup>5</sup> is a fundamental constant of nature describing phase transition from microscopic to cosmic scale. In this contribution the relatively small volume ratio of the Great Pyramid was compared to that of selected convex polyhedral solids such as the <em>Platonic </em>solids respectively the face-rich truncated icosahedron (bucky ball) as one of <em>Archimedes</em>’ solids leading to effective filling of the polyhedron by its in-sphere and therefore the highest volume ratio of the selected examples. The smallest ratio was found for the Great Pyramid. A regression analysis delivers the highly reliable volume ratio relation <img src="Edit_79e766ce-5580-4ae0-a706-570e0f3f1bd8.bmp" alt="" />, where <em>nF</em> represents the number of polyhedron faces and b approximates the silver mean. For less-symmetrical solids with a unique axis (tetragonal pyramids) the in-sphere can be replaced by a biaxial ellipsoid of maximum volume to adjust the <em>R</em><sub><em>V</em></sub> relation more reliably. 展开更多
关键词 polyhedron Great Pyramid Platonic Solids Volume-Area Ratio In-Sphere and In-Ellipsoid Polyhedral Void Space Golden and Silver Mean
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Optimal fuzzy PID controller with adjustable factors based on flexible polyhedron search algorithm 被引量:2
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作者 谭冠政 肖宏峰 王越超 《Journal of Central South University of Technology》 EI 2002年第2期128-133,共6页
A new kind of optimal fuzzy PID controller is proposed, which contains two parts. One is an on line fuzzy inference system, and the other is a conventional PID controller. In the fuzzy inference system, three adjustab... A new kind of optimal fuzzy PID controller is proposed, which contains two parts. One is an on line fuzzy inference system, and the other is a conventional PID controller. In the fuzzy inference system, three adjustable factors x p, x i , and x d are introduced. Their functions are to further modify and optimize the result of the fuzzy inference so as to make the controller have the optimal control effect on a given object. The optimal values of these adjustable factors are determined based on the ITAE criterion and the Nelder and Mead′s flexible polyhedron search algorithm. This optimal fuzzy PID controller has been used to control the executive motor of the intelligent artificial leg designed by the authors. The result of computer simulation indicates that this controller is very effective and can be widely used to control different kinds of objects and processes. 展开更多
关键词 OPTIMAL fuzzy inference PID controller adjustable factor flexible polyhedron search algorithm intelligent artificial leg
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Improved non-uniform subdivision scheme with modified Eigen-polyhedron
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作者 Jingjing Zhang Yufeng Tian Xin Li 《Visual Computing for Industry,Biomedicine,and Art》 EI 2022年第1期214-223,共10页
In this study,a systematic refinement method was developed for non-uniform Catmull-Clark subdivision surfaces to improve the quality of the surface at extraordinary points(EPs).The developed method modifies the eigenp... In this study,a systematic refinement method was developed for non-uniform Catmull-Clark subdivision surfaces to improve the quality of the surface at extraordinary points(EPs).The developed method modifies the eigenpolyhedron by designing the angles between two adjacent edges that contain an EP.Refinement rules are then formulated with the help of the modified eigenpolyhedron.Numerical experiments show that the method significantly improves the performance of the subdivision surface for non-uniform parameterization. 展开更多
关键词 Subdivision surface Eigen polyhedron Non-uniform Catmull-Clark surface
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Fast,Exact and Robust Set Operations on Polyhedrons Using Localized Constructive Solid Geometry Trees
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作者 Ping Lu Xudong Jiang +2 位作者 Wei Lu Ran Wei Bin Sheng 《ZTE Communications》 2015年第3期57-66,共10页
Regularized Boolean operations have been widely used in 3D modeling systems. However, evaluating Boolean operations may be quite numerically unstable and time consuming, especially for iterated set operations. A novel... Regularized Boolean operations have been widely used in 3D modeling systems. However, evaluating Boolean operations may be quite numerically unstable and time consuming, especially for iterated set operations. A novel and unified technique is proposed in this paper for computing single and iterated set operations efficiently, robustly and exactly. An adaptive octree is combined with a nested constructive solid geometry (CSG) tree by this technique. The intersection handling is restricted to the cells in the octree where intersection actually occurs. Within those cells, a CSG tree template is instanced by the surfaces and the tree is converted to planebased binary space partitioning (BSP) for set evaluation; Moreover, the surface classification is restricted to the ceils in the octree where the surfaces only come from a model and are within the bounding-boxes of other polyhedrons. These two ways bring about the efficiency and scalability of the operations, in terms of runtime and memory. As all surfaces in such a cell have the same classification relation, they are classified as a whole. Robustness and exactness are achieved by integrating plane-based geometry representation with adaptive geometry predicate technique in intersection handling, and by applying divide-and-conquer arithmetic on surface classification. Experimental results demonstrate that the proposed approach can guarantee the robustness of Boolean computations and runs faster than other existing approaches. 展开更多
关键词 Boolean operations polyhedrons constructive solid geometry binary space partitioning tree
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Ferromagnetic Calculation of Terbium Dysprosium and Holmium with Polyhedron Electron Shell
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作者 Zilong Kong 《Journal of Modern Physics》 2015年第13期1776-1780,共5页
Based on the regular polyhedron model of multi-electronic atom combined with the Bohr hypothesis, the following supposition is put forward: the electron momentum multiplied by the inscribed sphere radius of edges of e... Based on the regular polyhedron model of multi-electronic atom combined with the Bohr hypothesis, the following supposition is put forward: the electron momentum multiplied by the inscribed sphere radius of edges of each regular polyhedron is equal to the Planck constant. The relationship between saturation magnetization rates and Planck constants is determined, and the ferromagnetism of atoms is obtained from regular dodecahedron and regular hexahedron. Then, terbium, dysprosium, and holmium saturation magnetization rate are obtained from electronic regular polyhedron configuration. Derivation of matter wave formula is from thermodynamics, avoiding over speed of light. 展开更多
关键词 Atomic Structure Regular polyhedron ELECTRON SHELL Ferromagnetism of TERBIUM DYSPROSIUM and HOLMIUM Matter Wave Formula
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The Atomic Regular Polyhedron Electronic Shell
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作者 Zilong Kong 《Journal of Modern Physics》 2013年第10期1-19,共19页
The periodic table of elements is arranged based on a series of regular polyhedron. The stability of inert gas atoms can be explained by the distribution of electrons, as well as their motion and magnetic force struct... The periodic table of elements is arranged based on a series of regular polyhedron. The stability of inert gas atoms can be explained by the distribution of electrons, as well as their motion and magnetic force structure. A magnetic force regular octahedron is proposed. It is a unique configuration that best satisfies the convergence of electrons moving in the same direction within regular polyhedra. In the case of an electrostatic force crust, the formal electron spin accounts for the crusts intrinsic magnetic moment exceeding the speed of light. If one is to consider that the electron has a magnetic outer layer and an electrostatic inner layer, then the question can be solved and abovementioned inference can provide the basis for magnetic force and momentum for the regular octahedron model. The electron periphery has twenty-petal adsorptive substances;the existence of adsorptive substance causes the magnetic force greater than the electrostatic force. Each electronic shell in the regular polyhedron is in accordance with the electron configuration of periodic table of elements;the kinetic track of each electron is a surface of regular polyhedron. The magnetic properties of iron, cobalt, and nickel can be explained by the regular dodecahedron electronic shell of an atom. The electron orbit converged from reverse direction can explain diamond. The adsorptive substances found in atomic nuclei and electrons are defined as magnetic particles called magnetons. The thermodynamic magneton theory can be better explained when it is analyzed using principles of thermodynamics, superconductivity, viscosity, and even in the creation of glass. The structure of the light is a helical line. 展开更多
关键词 ATOMIC Structure REGULAR polyhedron ELECTRONIC SHELL Periodic TABLE of Elements Light Diamond
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Solvothermal Synthesis of Polyhedron Cobalt Nanomaterials
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作者 ALHALILI Zahrah 《Computer Aided Drafting,Design and Manufacturing》 2010年第1期78-82,共5页
Co nanostructure tetradecahedron shape like were prepared via a simple solvothermal route. The shape and size of Co nanopolyhedron were tuned by changing the volume composition of the solvents and the synthesis temper... Co nanostructure tetradecahedron shape like were prepared via a simple solvothermal route. The shape and size of Co nanopolyhedron were tuned by changing the volume composition of the solvents and the synthesis temperature. Phase purity was confirmed by X-ray diffraction (XRD) and crystal size was determined by scanning electron microscopy (SEM). The magnetic hysteresis loops of the polyhedron wareneasured using a SQUID magnetometer at 5 and 300 K. The results show ferromagnetic characteristics with coercivities of 22 and 15 Oe, respectively. 展开更多
关键词 FABRICATION polyhedron COBALT NANOMATERIALS MAGNETIC
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Two Algorithms for Fast Polyhedron Ray-Tracing
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作者 Zhang Qian Shi Jiaoying CaiHong CAD & CG State Key Lab., Zhejiang University, 310027 Foshan Enterprise Postdoctoral Workstaion 528000 《Computer Aided Drafting,Design and Manufacturing》 1997年第2期45-51,共0页
This note presents two fast polyhedron ray-tracing algorithms that can be applied not only in ray-convex polyhedron intersection, but also in ray-concave polyhedron intersection (Algorithm 2 permits polygons to contai... This note presents two fast polyhedron ray-tracing algorithms that can be applied not only in ray-convex polyhedron intersection, but also in ray-concave polyhedron intersection (Algorithm 2 permits polygons to contain internal loops of not).In the basis of surface trian gulation, Algorithm 1 can accelerate the surface normal vector interpolation by the intersection point's parameters. And besides, Algorithm 2 does not need any pre_procession such as surface triangulation. Moreover, it requires a few memories with more difficult operations such as division, extraction of roots and transcendental functions avoided entirely. Their simplicity and efficiency permit easy software or hardware implementation. 展开更多
关键词 ray_tracing polyhedron INTERSECTION
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Ternary alloy and metal oxides embedded in yolk–shell polyhedrons as bifunctional oxygen electrocatalyst 被引量:1
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作者 Yi Zhang Jia-Dan Lu +2 位作者 Guang-Xun Zhang Rong-Mei Zhu Huan Pang 《Rare Metals》 SCIE EI CAS CSCD 2024年第2期478-488,共11页
To improve the efficiency of oxygen electrolysis,exploiting bifunctional electrocatalysts with excellent activity and stability is extremely important due to the four-electron transfer dynamics of oxygen evolution rea... To improve the efficiency of oxygen electrolysis,exploiting bifunctional electrocatalysts with excellent activity and stability is extremely important due to the four-electron transfer dynamics of oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).Herein,a series of yolk-shell hollow polyhedrons(YHPs)embedded with NiCoFe ternary alloy and metal oxides,which are named YHP-x(x=1,2,3,4),were reported.By controlled etching multi-layered zeolitic imidazolate frameworks and following pyrolytic integration,YHPs are endowed with mass transfer tunnels,accessible inner active sites,and good electrical conductivity.Due to the synergetic effect of the alloy,metal oxides and the yolk-shell structure,YHP-1 exhibits excellent ORR performance with a half-wave potential of 0.79 V and YHP-2 displays superior OER performance with a low overpotential of 257 mV at 10 mA cm−2.The strategy described in this work can be extended to a number of hollow/yolk-shell electrocatalysts for water splitting and metal–air batteries. 展开更多
关键词 Metal oxides and alloy Oxygen evolution Oxygen reduction Yolk-shell polyhedron
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Enhance gas-separation efficiency of mixed matrix membranes by lamellarly arranged metal-organic polyhedron 被引量:1
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作者 Yida Yang Bowen Pang +5 位作者 Wang Zeng Bingxu Ma Panchao Yin Shenglin Yao Xiufang Wen Wei Zhang 《Nano Research》 SCIE EI CSCD 2023年第8期11450-11454,共5页
Eliminating the nonselective permeation path inside the mixed-matrix membranes(MMMs)is critical for fabrication of gas separation membranes.We demonstrate that by utilizing the phase separation of block copolymers,we ... Eliminating the nonselective permeation path inside the mixed-matrix membranes(MMMs)is critical for fabrication of gas separation membranes.We demonstrate that by utilizing the phase separation of block copolymers,we are able to introduce metal-organic polyhedrons(MOPs)with precise pore sizes into a polymer matrix and form an ordered layered structure.We also prove that,by arranging MOP cages into a continuous nanosheet-like layer structure,we are able to generate repeated MOP-effective pathways and deplete the MOP-free permeation pathways,thus enhancing the gas-separation efficiency of MMMs. 展开更多
关键词 metal-organic polyhedrons(MOPs) mixed-matrix membranes(MMMs) phase separation of mixed-matrix membranes arrangement of MOPs
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Excess Activity Tuned by Distorted Tetrahedron in CoMoO_(4) for Oxygen Evolution
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作者 Hengbo Xiao Kai Chi +10 位作者 Hongxia Yin Xiangji Zhou Pengxiang Lei Peizhi Liu Jiakun Fang Xiuhong Li Songliu Yuan Zhen Zhang Yaqiong Su Junjie Guo Lihua Qian 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期247-252,共6页
Oxygen vacancies enable modulating surface reconstruction of transition metal oxides containing metal-oxygen polyhedrons into metallic oxyhydroxide for oxygen evolution reaction(OER),while revealing reconstructing mec... Oxygen vacancies enable modulating surface reconstruction of transition metal oxides containing metal-oxygen polyhedrons into metallic oxyhydroxide for oxygen evolution reaction(OER),while revealing reconstructing mechanism is stuck by the requirement to precisely control exact sites of these vacancies.Herein,oxygen vacancies are localized only within MoO_(4)tetrahedrons rather than CoO_(6)octahedrons in CoMoO_(4)catalyst,guaranteeing coherent reconstruction of CoO_(6)octahedrons into pure CoOOH with tunable activities for OER.Meanwhile,distorted tetrahedron accelerates the dissolution of Mo atoms into alkaline electrolyte,triggering spontaneous transition of partial CoMoO_(4)into Co(OH)_(2).CoO_(6)octahedrons in both CoMoO_(4)and Co(OH)_(2)can transform pure CoOOH completely at lower potential,resulting in excess intrinsic activity whose summit is identified by overpotential at 10 mA cm^(-2)with 22.9%reduction and Tafel slope with 65.3%reduction.Well-defined manipulation over the distorted polyhedrons offers one versatile knob to precisely modulate electronic structure of oxide catalysts with outstanding OER performance. 展开更多
关键词 metal-oxygen polyhedron oxygen evolution reaction oxygen vacancy Raman spectroscopy
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灵活性资源聚合参考模型与量化指标体系 被引量:10
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作者 王思远 吴文传 《电力系统自动化》 EI CSCD 北大核心 2024年第3期1-9,共9页
高比例新能源并网给电网带来了显著的波动性和不确定性,使受端电网面临可调节资源能力不足的问题,需要充分利用大量的灵活性资源参与电网调度并提供辅助服务。然而,灵活性资源的数量众多、分布广泛且特性各异,给资源的集中调控带来了新... 高比例新能源并网给电网带来了显著的波动性和不确定性,使受端电网面临可调节资源能力不足的问题,需要充分利用大量的灵活性资源参与电网调度并提供辅助服务。然而,灵活性资源的数量众多、分布广泛且特性各异,给资源的集中调控带来了新的挑战,需要以集群的形式对灵活性资源进行管理和调度。为了更加准确地评估集群在电网调控中的作用,需要将灵活性资源进行聚合,并根据应用需求采用适当的量化指标衡量其性能。基于灵活性资源集群在电网调度和电力市场中的应用需求,提出了评估灵活性资源集群可调节能力的量化指标体系。根据物理特性,将其分为类发电机特性、类储能特性和共有特性3类。为了实现不同应用场景下对集群灵活性指标的量化评估,构建了由等效发电机和等效储能所组成的灵活性资源集群的聚合参考模型。此聚合参考模型具有直观的物理意义和良好的多重嵌套特性,并适用于多种时间尺度和多种能量形式,可以被用于计算特定应用场景下的量化性能指标,以及应用于分布式资源集群的异步调度、综合能源系统的联合优化调度、虚拟电厂参与电力市场的投标报价等多个场景中。 展开更多
关键词 灵活性资源 聚合参考模型 量化指标体系 高维多面体投影 电力系统
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基于Au@4-ATP@Au凸多面纳米颗粒的多菌灵表面增强拉曼散射检测 被引量:1
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作者 严霞 胡聪聪 +3 位作者 杨智远 赵航 史晓凤 马君 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第7期1843-1851,共9页
表面增强拉曼散射(SERS)技术在农药残留的检测方面具有很大的潜力,但在痕量和定量分析方面仍存在局限性。提出了一种基于Au@4-ATP@Au凸多面纳米颗粒(NCPs-Au@4-ATP@Au)为增强基底的农药检测方法。XRD结果表明,由于探针分子对金前驱的选... 表面增强拉曼散射(SERS)技术在农药残留的检测方面具有很大的潜力,但在痕量和定量分析方面仍存在局限性。提出了一种基于Au@4-ATP@Au凸多面纳米颗粒(NCPs-Au@4-ATP@Au)为增强基底的农药检测方法。XRD结果表明,由于探针分子对金前驱的选择性和诱导性,NCPs-Au@4-ATP@Au纳米颗粒与球形金纳米颗粒晶面结构信息有明显差异,具体体现在(200)处的强反射峰。结合扫描电镜与吸收光谱可以确定,NCPs-Au@4-ATP@Au同时具备球形与多面体结构特征。吸收峰较球形金纳米颗粒有明显红移,更加接近激发光波长,这在理论上更有利于SERS信号的增强。实验证明,以表面包覆高指数晶面,同时内嵌4-ATP作为探针分子的NCPs-Au@4-ATP@Au为增强基底,农药多菌灵(CBZ)的检测限(LODs)达到0.66 nmol·L^(-1)。通过对CBZ分子的拉曼与SERS光谱位移分析可以初步确定,CBZ分子是通过NH键和CO键吸附于金纳米颗粒上。Au@4-ATP@Au利用多凸面结构体提高灵敏度的同时,以4-ATP作为定标信号,归一后光谱稳定性和时效性也得到改善。内标峰强度矫正后光谱稳定性的相对标准偏差(relative standard deviation,RSD)低至7.03%,半个月内信号强度仅降低5.87%,RSD为2.94%。结果表明,NCPs-Au@4-ATP@Au提高了SERS在农药检测方面的痕量和定量检测能力,该基底有望推动SERS在实际中的应用。 展开更多
关键词 表面增强拉曼散射 多菌灵 凸多面纳米颗粒 定量分析 内定标
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基于联络线可行域分析的跨区通道传输能力评估方法
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作者 袁泉 马骞 +5 位作者 李豹 王子强 周鑫 张蔷 孙宇军 赖晓文 《电力自动化设备》 EI CSCD 北大核心 2024年第9期170-178,共9页
跨区通道传输能力是区域调度机构预编制和下达送受电计划的关键参考信息。综合考虑多个相关子区域电网在不同时段运行边界的共同影响,有助于增强通道能力评估的全面性。提出一种基于联络线可行域分析的跨区通道传输能力评估方法。考虑... 跨区通道传输能力是区域调度机构预编制和下达送受电计划的关键参考信息。综合考虑多个相关子区域电网在不同时段运行边界的共同影响,有助于增强通道能力评估的全面性。提出一种基于联络线可行域分析的跨区通道传输能力评估方法。考虑子区域的平衡、安全以及时段耦合等约束条件,计算各子区域电网在各时段的联络线可行域;利用不同子区域可行域的组合、提升-投影策略求得全网运行视角下关键送受电通道的可行域结果,并借助可行域顶点与极限传输功率的对应关系评估跨区通道的传输能力。基于两区域及三区域互联系统的运行场景进行算例分析,验证所提方法的有效性。 展开更多
关键词 联络线 可行域 跨区通道 传输能力 多面体投影 顶点搜索法
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一种6-DOF小行星着陆轨迹序列凸优化方法
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作者 初彦峰 穆荣军 +1 位作者 梁浩 崔乃刚 《宇航学报》 EI CAS CSCD 北大核心 2024年第3期341-351,共11页
针对6自由度的小行星动力着陆多约束轨迹优化问题,提出了一种基于序列凸优化的小行星着陆轨迹优化算法。首先采用多面体引力场模型计算小行星的引力场,其可用于描述任意形状的小行星引力场,且比质点群法和球谐函数展开法等方法计算精度... 针对6自由度的小行星动力着陆多约束轨迹优化问题,提出了一种基于序列凸优化的小行星着陆轨迹优化算法。首先采用多面体引力场模型计算小行星的引力场,其可用于描述任意形状的小行星引力场,且比质点群法和球谐函数展开法等方法计算精度更高。为了在凸约束下解决小行星着陆过程燃料消耗最优问题,通过对探测器动力学模型及其约束进行线性化和离散化,将原来的非凸连续时间优化问题转化为凸化的子问题,即二阶锥规划问题(SOCP);然后引入了虚拟控制项和信赖域,以增强算法的鲁棒性。通过在形状不规则小行星上的着陆模拟,验证了所提出算法的有效性,仿真结果满足各项约束条件,可实现高精度着陆和燃料消耗最优的目标。 展开更多
关键词 小行星着陆 多面体引力场模型 6自由度 序列凸优化
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低轮廓电解铜箔表面微细粗化工艺研究
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作者 凌羽 卢伟伟 +5 位作者 宋克兴 刘海涛 武玉英 杨祥魁 樊斌锋 王庆福 《精密成形工程》 北大核心 2024年第7期173-181,共9页
目的针对低轮廓电解铜箔剥离强度不足的问题,进行铜箔表面微细粗化处理研究,通过在铜箔表面生成可控形态的针状结构粗化层,以期在不影响低轮廓铜箔表面整体轮廓的条件下,提高铜箔的抗剥离性能。方法采用电化学微细粗化法,以NaOH和K_(2)S... 目的针对低轮廓电解铜箔剥离强度不足的问题,进行铜箔表面微细粗化处理研究,通过在铜箔表面生成可控形态的针状结构粗化层,以期在不影响低轮廓铜箔表面整体轮廓的条件下,提高铜箔的抗剥离性能。方法采用电化学微细粗化法,以NaOH和K_(2)S_(2)O_(8)的混合溶液为粗化电解液,研究电流密度、NaOH浓度及K_(2)S_(2)O_(8)浓度等主要工艺参数对铜箔表面针状结构形貌、粗糙度及铜箔剥离强度的影响。结果经过微细粗化处理后,低轮廓电解铜箔表面形成了针状多面体结构,在粗化电流密度为1.5 A/dm^(2)、粗化液中NaOH质量浓度为100 g/L、K_(2)S_(2)O_(8)质量浓度为20 g/L的条件下,粗化层形成的针状多面体结构致密且均匀,铜箔的剥离强度提升至0.48 N/mm。结论通过电化学微细粗化法,在低轮廓电解铜箔表面成功制备了针状结构的粗化层,通过优化微细粗化工艺参数,实现了铜箔表面针状结构粗化层的可控制备,在保证铜箔低表面粗糙度的同时,有效提高了铜箔的剥离强度。 展开更多
关键词 电解铜箔 微细粗化处理 针状多面体 粗糙度 剥离强度
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Synthesis and facet-dependent photocatalytic activity of strontium titanate polyhedron nanocrystals 被引量:5
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作者 Junfang Li Hua Bai +5 位作者 Wencai Yi Jingyao Liu Yahui Li Qing Zhang Haifeng Yang Guangcheng Xi 《Nano Research》 SCIE EI CAS CSCD 2016年第5期1523-1531,共9页
Cubic-perovskite (SrTiO3) has a great potential to be utilized in a wide range of applications. However, currently very little is known about the shape and facet effects of SrTiO3 on their physicochemical properties... Cubic-perovskite (SrTiO3) has a great potential to be utilized in a wide range of applications. However, currently very little is known about the shape and facet effects of SrTiO3 on their physicochemical properties. This is largely owing to the difficulties in controlling the morphology of facets during synthesis. Herein, we describe a facile route for the facet- and size-controlled fabrication of single- crystalline SrTiO3 triangular prisms with highly exposed {101} side faces and {111} end faces. Theoretical and experimental studies of their photocatalytic performance have shown that triangular prisms exhibit superior photocatalytic activities than nanocubes with exposed (001) faces for the degradation of organic contaminants, which may be primarily attributed to the much higher surface energy of {101} facets (2.97 J/m^2) and {111} facets (2.80 J/m^2) than of that of {001} facets (0.98 J/m^2). 展开更多
关键词 polyhedron perovskite strontium titanate active faces PHOTOCATALYSIS
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