High-efficiency sodium storage of Co_(0.85)Se/WSe_(2) encapsulated in N-doped carbon polyhedron via vacancy and heterojunction engineering

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.

Facile synthesis of the Mn_(3)O_(4)polyhedron grown on N-doped honeycomb carbon as high-performance negative material for lithium-ion batteries

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.

灵活性资源聚合参考模型与量化指标体系

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。

Excess Activity Tuned by Distorted Tetrahedron in CoMoO_(4) for Oxygen Evolution

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.

船舶动力定位非线性模型预测控制

针对受船舶运动状态和推力饱和约束影响的动力定位控制问题,本文提出了一种非线性模型预测控制方法。依据多面体描述理论建立了船舶动力定位多面体描述偏差模型,针对上述模型采用线性矩阵不等式设计非线性模型预测控制器中的终端要素,并证明了闭环系统的稳定性。仿真结果表明:设计的控制器能在满足约束条件和受环境干扰条件下快速控制船舶稳定在计划航向和计划船位,验证了控制器的有效性和本质鲁棒性。

Unique NiFe–NiCoO2 hollow polyhedron as bifunctional electrocatalysts for water splitting

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.

Optimal fuzzy PID controller with adjustable factors based on flexible polyhedron search algorithm

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.

Ratio of In-Sphere Volume to Polyhedron Volume of the Great Pyramid Compared to Selected Convex Polyhedral Solids

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 RV = π ⋅ φ5, where is the golden mean. It is important that the number φ5 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 Platonic solids respectively the face-rich truncated icosahedron (bucky ball) as one of Archimedes’ 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 , where nF 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 RV relation more reliably.

Improved non-uniform subdivision scheme with modified Eigen-polyhedron

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.

Fast,Exact and Robust Set Operations on Polyhedrons Using Localized Constructive Solid Geometry Trees

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.

Ferromagnetic Calculation of Terbium Dysprosium and Holmium with Polyhedron Electron Shell

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.

The Atomic Regular Polyhedron Electronic Shell

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.

Solvothermal Synthesis of Polyhedron Cobalt Nanomaterials

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.

Two Algorithms for Fast Polyhedron Ray-Tracing

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.

基于正十二面体靶标多机器人定位系统研究

针对基于单目视觉的室内定位系统精度差的问题,提出了一种基于AprilTag标签和正多面体的正十二面体AprilTag靶标,并通过单目视觉检测该靶标的相对空间位姿。该靶标装置通过在正十二面体各个表面粘贴AprilTag标签,扩展了靶标的检测范围,同时结合多面体之间的约束关系,提升了位姿检测精度。通过搭建实验平台实施该靶标的位姿检测精度验证,实验结果表明提出的正十二面体AprilTag靶标的相对位姿检测精度明显优于单个AprilTag标签位姿检测精度,当采用相同尺寸的AprilTag标签时,相对位置误差降低了约83.6%,同时在3个轴向上的相对姿态误差分别减少了约95.2%、94.6%、89.1%。

计及风电相关性的区域综合能源系统多时间尺度优化调度

为解决源荷不确定性和风电相关性导致区域综合能源系统调度结果可信度低的问题,以综合运行成本最小为目标,提出一种计及多时间尺度的区域综合能源系统调度模型。在日前阶段,提出计及风电相关性的两阶段鲁棒优化模型,使用列和约束生成法进行迭代求解。日内调度阶段考虑了冷热电响应速率的不同,提出基于模型预测控制的冷热电分层滚动优化模型,进一步消除源荷功率波动。仿真结果表明:计及风电相关性的鲁棒优化方法降低了保守性,提高了经济性;在冷热电分层优化时使用模型预测控制,实现了区域综合能源系统的经济及稳定运行。

Ternary alloy and metal oxides embedded in yolk–shell polyhedrons as bifunctional oxygen electrocatalyst

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.

五轴(3+2)加工中心坐标系转换与优化技术研究

针对具有多个面均有加工要求的多面体零件,讨论了五轴(3+2)加工中心,且不具有五轴联动和Rtcp刀尖跟随功能机床的坐标系转换和优化问题。在基于同一个坐标系的前提下,完成包含平面、孔、凸台、型腔及轮廓等几何特征的多个面精度加工要求,同时完成任意角度固定轴的钻孔及轮廓铣削的加工要求,是一次坐标系转换与优化技术的综合应用。研究编制了NX软件加工程序,利用TCL语言修改定制后处理文件,利用三维空间坐标的旋转算法编制宏程序,将NX软件生成的程序与宏程序建立联系作为转换新程序。机床运行该程序时自动调用宏程序内容实现对坐标值的实时数学计算转换,从而计算出坐标轴旋转后新的坐标值。刀具根据该坐标值进行切削加工,采用该技术,一次装夹完成所有面的加工任务,不仅提高了加工精度,同时也大大拓展了机床的加工能力,减轻了多次找正坐标系的重复劳动,提高了加工效率,是一种后处理、宏程序及坐标系之间优化技术的实际应用,对于类似多面体零件的加工具有借鉴意义。

家蚕Polh^+ Bac-to-Bac杆状病毒表达系统的构建

为利用杆状病毒的强启动子——多角体启动子而构建的重组杆状病毒一般是多角体缺失型(polh-)病毒。为了解决家蚕生物反应器规模化生产中病毒必需经皮接种而效率低下的问题,在建立家蚕Bac-to-Bac快速表达系统的基础上,构建了能形成多角体的家蚕Polh+ Bac-to-Bac表达系统。通过该系统能够产生表达外源目的基因的重组病毒,获得的该重组病毒能在培养细胞内表达,也能通过经口添食感染表达。利用EGFP报告基因分析了该系统的表达效果,构建的重组病毒不仅有效表达了EGFP蛋白,还在细胞核中形成了大量多角体。该系统较好解决了重组病毒必需经皮接种感染的缺陷,提高了生产效率,拓宽了杆状病毒在生物杀虫剂、基因治疗等领域的应用前景。

负离子配位多面体生长基元在晶体生长中的应用

It has been pointed out by the theoretic model of anion coordination polyhedra of growth units that the crystal form is dominated by the stability of combination of anion coordination polyhedra on the growth interface.The face has the fastest growth rate and disappears easily if the vertex of coordination polyhedron is pointed at.The face has the slowest growth rate and appears easily if the plane of coordination polyhedron is pointed at.The growth rate is in median for the face that the edge of coordination polyhedron is pointed at.A few of problems are discussed in the paper on the basis of this theory. (1)Several examples of the morphology of allomorph and homoeomorphism are given in the paper.There are three allomorphs of TiO 2 rutile,brookite and anatase.The morphology of these allomorphs are totally different because the stability of combination of octahedral [Ti O 6] 8- vary with the orientation and linked edges of coordination polyhedra.Another example is the homoeomorphism of cassiterite SnO 2.The orientation and combination of octahedral [Sn O 6] 8- in cassiterite are similar to that of octahedral [Ti O 6] 8- in rutile,so that cassiterite and rutile have similar morphology even for their form of twin and twin face.The combination of octahedral [Al O 6] 9- ,[Fe O 6] 9- and [Ti O 6] 8- respectively is similar at the orientation and linked form of coordination polyhedra in three crystals of corundum,hematite and ilmenite,so the same faces appear in these three crystals,resulted in similar morphology.