Three-dimensionally interconnected Co9S8/MWCNTs composite cathode host for lithium–sulfur batteries

Several challenging issues,such as the poor conductivity of sulfur,shuttle effects,large volume change of cathode,and the dendritic lithium in anode,have led to the low utilization of sulfur and hampered the commercialization of lithium–sulfur batteries.In this study,a novel three-dimensionally interconnected network structure comprising Co9 S8 and multiwalled carbon nanotubes(MWCNTs)was synthesized by a solvothermal route and used as the sulfur host.The assembled batteries delivered a specific capacity of1154 m Ah g-1 at 0.1 C,and the retention was 64%after 400 cycles at 0.5 C.The polar and catalytic Co9 S8 nanoparticles have a strong adsorbent effect for polysulfide,which can effectively reduce the shuttling effect.Meanwhile,the three-dimensionally interconnected CNT networks improve the overall conductivity and increase the contact with the electrolyte,thus enhancing the transport of electrons and Li ions.Polysulfide adsorption is greatly increased with the synergistic effect of polar Co9 S8 and MWCNTs in the three-dimensionally interconnected composites,which contributes to their promising performance for the lithium–sulfur batteries.

The Monty Hall Problem and beyond: Digital-Mathematical and Cognitive Analysis in Boole’s Algebra, Including an Extension and Generalization to Related Cases

The Monty Hall problem has received its fair share of attention in mathematics. Recently, an entire monograph has been devoted to its history. There has been a multiplicity of approaches to the problem. These approaches are not necessarily mutually exclusive. The design of the present paper is to add one more approach by analyzing the mathematical structure of the Monty Hall problem in digital terms. The structure of the problem is described as much as possible in the tradition and the spirit—and as much as possible by means of the algebraic conventions—of George Boole’s Investigation of the Laws of Thought (1854), the Magna Charta of the digital age, and of John Venn’s Symbolic Logic (second edition, 1894), which is squarely based on Boole’s Investigation and elucidates it in many ways. The focus is not only on the digital-mathematical structure itself but also on its relation to the presumed digital nature of cognition as expressed in rational thought and language. The digital approach is outlined in part 1. In part 2, the Monty Hall problem is analyzed digitally. To ensure the generality of the digital approach and demonstrate its reliability and productivity, the Monty Hall problem is extended and generalized in parts 3 and 4 to related cases in light of the axioms of probability theory. In the full mapping of the mathematical structure of the Monty Hall problem and any extensions thereof, a digital or non-quantitative skeleton is fleshed out by a quantitative component. The pertinent mathematical equations are developed and presented and illustrated by means of examples.

Higher Variations of the Monty Hall Problem (3.0, 4.0) and Empirical Definition of the Phenomenon of Mathematics, in Boole’s Footsteps, as Something the Brain Does

In Advances in Pure Mathematics (www.scirp.org/journal/apm), Vol. 1, No. 4 (July 2011), pp. 136-154, the mathematical structure of the much discussed problem of probability known as the Monty Hall problem was mapped in detail. It is styled here as Monty Hall 1.0. The proposed analysis was then generalized to related cases involving any number of doors (d), cars (c), and opened doors (o) (Monty Hall 2.0) and 1 specific case involving more than 1 picked door (p) (Monty Hall 3.0). In cognitive terms, this analysis was interpreted in function of the presumed digital nature of rational thought and language. In the present paper, Monty Hall 1.0 and 2.0 are briefly reviewed (§§2-3). Additional generalizations of the problem are then presented in §§4-7. They concern expansions of the problem to the following items: (1) to any number of picked doors, with p denoting the number of doors initially picked and q the number of doors picked when switching doors after doors have been opened to reveal goats (Monty Hall 3.0;see §4);(3) to the precise conditions under which one’s chances increase or decrease in instances of Monty Hall 3.0 (Monty Hall 3.2;see §6);and (4) to any number of switches of doors (s) (Monty Hall 4.0;see §7). The afore-mentioned article in APM, Vol. 1, No. 4 may serve as a useful introduction to the analysis of the higher variations of the Monty Hall problem offered in the present article. The body of the article is by Leo Depuydt. An appendix by Richard D. Gill (see §8) provides additional context by building a bridge to modern probability theory in its conventional notation and by pointing to the benefits of certain interesting and relevant tools of computation now available on the Internet. The cognitive component of the earlier investigation is extended in §9 by reflections on the foundations of mathematics. It will be proposed, in the footsteps of George Boole, that the phenomenon of mathematics needs to be defined in empirical terms as something that happens to the brain or something that the brain does. It is generally assumed that mathematics is a property of nature or reality or whatever one may call it. There is not the slightest intention in this paper to falsify this assumption because it cannot be falsified, just as it cannot be empirically or positively proven. But there is no way that this assumption can be a factual observation. It can be no more than an altogether reasonable, yet fully secondary, inference derived mainly from the fact that mathematics appears to work, even if some may deem the fact of this match to constitute proof. On the deepest empirical level, mathematics can only be directly observed and therefore directly analyzed as an activity of the brain. The study of mathematics therefore becomes an essential part of the study of cognition and human intelligence. The reflections on mathematics as a phenomenon offered in the present article will serve as a prelude to planned articles on how to redefine the foundations of probability as one type of mathematics in cognitive fashion and on how exactly Boole’s theory of probability subsumes, supersedes, and completes classical probability theory. §§2-7 combined, on the one hand, and §9, on the other hand, are both self-sufficient units and can be read independently from one another. The ultimate design of the larger project of which this paper is part remains the increase of digitalization of the analysis of rational thought and language, that is, of (rational, not emotional) human intelligence. To reach out to other disciplines, an effort is made to describe the mathematics more explicitly than is usual.

Hall Effects on Unsteady MHD Three Dimensional Flow through a Porous Medium in a Rotating Parallel Plate Channel with Effect of Inclined Magnetic Field

In this paper, we make an initial value investigation of the unsteady flow of incompressible viscous fluid between two rigid non-conducting rotating parallel plates bounded by a porous medium under the influence of a uniform magnetic field of strength H0 inclined at an angle of inclination α with normal to the boundaries taking hall current into account. The perturbations are created by a constant pressure gradient along the plates in addition to the non-torsional oscillations of the upper plate while the lower plate is at rest. The flow in the porous medium is governed by the Brinkman’s equations. The exact solution of the velocity in the porous medium consists of steady state and transient state. The time required for the transient state to decay is evaluated in detail and the ultimate quasi-steady state solution has been derived analytically. Its behaviour is computationally discussed with reference to the various governing parameters. The shear stresses on the boundaries are also obtained analytically and their behaviour is computationally discussed.

医院EPC项目管理协同度评价研究

为提高医院EPC项目管理效率,首先,依据霍尔的三维结构模式(Hard System Methodology,HSM)并结合医院工程总承包(Engineering Procurement Construction,EPC)项目的特点,构建了一个涵盖业务、组织、过程、信息、制度和资源六大子系统的医院EPC项目管理协同系统模型,基于此建立了医院EPC管理协同度评价指标体系;然后,运用改进的层次分析法确定指标权重,并结合序参量功效函数法对项目协同度进行量化计算,以此构建了医院EPC项目管理协同度评价模型;最后,以济南市某医院EPC项目为例,分析得出该项目各阶段的管理协同度、各子系统有序度及各序参量指标的敏感性程度。结果表明:该项目设计阶段和采购阶段的管理协同度处于低度协同水平,施工阶段处于低度不协同水平;在各子系统中,制度协同、业务协同、过程协同的有序度较低,应针对识别出的高敏感性指标进行改进。

自动化集装箱码头标准体系构建与评价研究

针对国内外自动化集装箱码头缺乏标准化顶层设计、标准需求不明确的问题,开展自动化集装箱码头标准体系研究及其适用性评价。首先,在总结国内外自动化集装箱码头标准化现状的基础上,提出了自动化集装箱码头标准体系构建的原则和方案类型;其次,参考已有相关标准体系架构,基于霍尔三维结构理论,构建了自动化集装箱码头标准体系框架,并提出了标准需求方向;最后,采用模糊综合评价法对标准体系进行量化评价。结果表明,该标准体系的综合评价值为8.783,总体上对自动化集装箱码头的实际发展具有良好支撑作用。根据体系分项评价分值,提出了体系优化和后续标准制定建议,为交通运输其他领域标准体系构建和评价提供案例参考。

基于进化曲线的大科学工程可靠性数据管理模型与成熟度研究

借鉴系统工程建模和技术进化思想,从系统理论和组织理论角度建立大科学工程可靠性数据管理模型,运用对象维、视图维和阶段维分别阐述可靠性数据管理的主要内容及相关共性。以此提出管理模型的成熟度曲线分析方法,运用S进化曲线分析大科学工程可靠性数据管理存在的跨装置差异性。并在神光系列装置建设中加以验证,实现可靠性工程管理的规范化和效率的有效改善。

基于霍尔三维结构的技术创新方法培训体系研究

在分析培训和推广技术创新方法重要性的基础上,结合霍尔三维结构模型,建立了培训推广技术创新方法的三维结构模型,明确了各阶段的目标和交付物。将"四元主体"模型运用于创新方法培训主体关系研究,根据主导驱动元素的不同把四元主体模型阶段分为政府推动型、机构推动型和自觉发展型3个主要表现形态,并阐述了四元主体与三维结构模型的关系。

用相关指数估算氯代羟基苯甲醛的色谱保留指数

基于化学拓扑理论,计算了25种氯代羟基苯甲醛衍生物的电拓扑状态指数(En)、连接性指数(mXpv)。用多元回归研究了这些化合物的色谱保留指数(R.I.)与En、mXpv的定量关系。经逐步回归分析,建立了最佳的定量结构—色谱保留指数相关(QSRR)模型:R.I.值=-649.379+824.837E6+461.0301Xvp,n′=22,R=0.988,F=398.22,S=28.78。用Jackknife法检验具有良好的稳健性与预测能力,其计算值与试验值基本吻合,优于文献结果。

综合管廊PPP项目全生命周期绩效评价体系研究

为有效解决综合管廊PPP项目绩效评价无法同时考虑每个阶段、各利益相关者的利益需求与工作执行情况等问题,运用霍尔三维结构,从利益相关者角度对其决策阶段、建设阶段、运营移交阶段的绩效评价指标进行识别,建立系统的绩效评价体系,为综合管廊PPP项目绩效评价提供参考。

建设项目全面造价管理三维结构与Agent系统研究

基于全面造价管理的系统特性和霍尔三维结构的思想,构建了建设项目全面造价管理的霍尔三维模型,并提出了全面造价管理的多Agent系统模型,为全面造价管理软件的实现提供了参考。