Synthesis of Co3O4 nano-octahedra enclosed by {111} facets and their excellent lithium storage properties as anode material of lithium ion batteries

Abstract
Nano-sized(nO-Co3O4, 387nm)andmicron-sized(mO-Co3O4, 6.65 mm) Co3O4 octahedraenclosedby
{111}facetshavebeenbothsynthesizedthroughawetchemicalmethodfollowedbythermal
treatment,andservedasanodematerialoflithium ionbatteries(LIBs).Electrochemicalresults
demonstratethatthenO-Co3O4 showsexcellentlongcyclabilityandratecapability.ThenO-Co3O4
candeliverastablechargecapacityashighas955.5mAhg1 upto200cycleswithoutnoticeable
capacityfadingatacharge/dischargecurrentdensityof0.1Ag1 (ca. 0.11C).Theexcellent
electrochemicalperformanceisascribedtothenano-sizeandthe{111}facetsthatenclosethe
octahedra. WhilethemO-Co3O4 could onlymaintain288.5mAhg1 after 200cycles,illustratingvery
poorcyclingperformance,whichisascribedtothelargeparticlesizethatmaycausehugevolume
changeduringrepeatedcharging/discharging process.TheresultsrevealthattheCo3O4 nano-
octahedrawouldbeapromisinganodematerialforthenext-generationofLIBs.

Material Management in Confined Site Construction

The objective of this paper is to identify various managerial issues encountered and resulting strategies adopted, with regards management of materials on confined construction site. This is achieved through classifying the various managerial burdens encountered with the numerous strategies adopted, for the successful management of such confined environments within the realm of materials management.


Through conducting an extensive literature review and detailed interviews, a comprehensive insight into the materials management concerns within a confined construction site environment is envisaged and portrayed. The following are the leading issues highlighted; (1)Lack of adequate storage space, (2)Work place becoming over-crowded, (3)Lack of adequate room for the effective handling of materials and (4)Difficult to transport materials around site. The leading managerial strategies to the management of materials on confined construction sites may be listed in order of importance, as follows; (1)Pre-fabrication and pre-assembly, (2)Providing adequate storage, (3)Space scheduling, (4)Just-In-Time delivery techniques, and (5)Effective design site layout.

Based on the research conducted, it can be concluded, that through effective management of the issues identified along with implementing the various strategies highlighted; successful materials management within a confined construction site environment is attainable.


Innovative Aspect of Paper: An empirical study of three different construction sites in three different countries (Ireland, England and USA) investigating the managerial issues and strategies relating to implementation of materials management in confined construction sites.

Rigorous Specification and Low-Latency Implementation of Technical Market Indicators

Technical market indicators are tools used by technical an- alysts to understand trends in trading markets. Technical (market) indicators are often calculated in real-time, as trading progresses. This paper presents a mathematically- founded framework for calculating technical indicators. Our framework consists of a domain specific language for the un- ambiguous specification of technical indicators, and a run- time system based on Click, for computing the indicators. We argue that our solution enhances the ease of program- ming due to aligning our domain-specific language to the mathematical description of technical indicators, and that it enables executing programs in kernel space for decreased latency, without exposing the system to users’ programming errors.

Nonlinear numerical modelling of lightning strike effect on composite panels with temperature dependent material properties

This paper presents a physics based modelling procedure to predict the thermal damage of composite material when struck by lightning. The procedure uses the Finite Element Method with non-linear material models to represent the extreme thermal material behaviour of the composite material (carbon/epoxy) and an embedded copper mesh protection system. Simulation predictions are compared against published experimental data, illustrating the potential accuracy and computational cost of virtual lightning strike tests and the requirement for temperature dependent material modelling. The modelling procedure is then used to examine and explain a number of practical solutions to minimize thermal material damage. © 2013 Elsevier Ltd.

NONLINEAR NUMERICAL MODELLING OF LIGHTENING STRIKE EFFECT ON COMPOSITE PANELS WITH TEMPERATURE DEPENDANT MATERIAL PROPERTIES

Lightning strike is one of the challenges that the aerospace industry is facing in an effort to increase the percentage of composite materials used in aircraft structures. Lightning strike damage is due to high orthotropic electric resistivity of the composite panels, which leads to high thermal loads that cause decomposition of the epoxy and delimitations of the laminates. Yet, experimental testing of lightning strike on aircraft panels is expensive due to the large number of design parameters that can control the inflicted damage. A coupled thermal-electrical finite element analysis is used to investigate the design variables space that can affect lightning strike damage on epoxy/graphite composite panels. The contribution of this study is modeling the composite panels’ material properties as temperature dependent, which was excluded by other researchers. A number of practical solutions to minimize the damage effect are proposed. Two set of experimental results are used to verify the numerical ones. One experimental set for plain composite panel, and second one for composite panels with joints

Heterogeneity assumptions in the specification of bargaining models: a study of household level trade-offs between commuting time and salary

With many real world decisions being made in conjunction with other decision makers, or single agent decisions having an influence on other members of the decision maker's immediate entourage, there is strong interest in studying the relative weight assigned to different agents in such contexts. In the present paper, we focus on the case of one member of a two person household being asked to make choices affecting the travel time and salary of both members. We highlight the presence of significant heterogeneity across individuals not just in their underlying sensitivities, but also in the relative weight they assign to their partner, and show how this weight varies across attributes. This is in contrast to existing work which uses weights assigned to individual agents at the level of the overall utility rather than for individual attributes. We also show clear evidence of a risk of confounding between heterogeneity in marginal sensitivities and heterogeneity in the weights assigned to each member. We show how this can lead to misleading model results, and argue that this may also explain past results showing bargaining or weight parameters outside the usual [0,1] range in more traditional joint decision making contexts. In terms of substantive results, we find that male respondents place more weight on their partner's travel time, while female respondents place more weight on their partner's salary.

A statistical analysis of circumstellar material in Type Ia supernovae

A key tracer of the elusive progenitor systems of Type Ia supernovae (SNe Ia) is the detection of narrow blueshifted time-varying Na I D absorption lines, interpreted as evidence of circumstellar material surrounding the progenitor system. The origin of this material is controversial, but the simplest explanation is that it results from previous mass-loss in a system containing a white dwarf and a non-degenerate companion star. We present new single-epoch intermediate-resolution spectra of 17 low-redshift SNe Ia taken with XShooter on the European Southern Observatory Very Large Telescope. Combining this sample with events from the literature, we confirm an excess (∼20 per cent) of SNe Ia displaying blueshifted narrow Na I D absorption features compared to redshifted Na I D features. The host galaxies of SNe Ia displaying blueshifted absorption profiles are skewed towards later-type galaxies, compared to SNe Ia that show no Na I D absorption and SNe Ia displaying blueshifted narrow Na I D absorption features have broader light curves. The strength of the Na I D absorption is stronger in SNe Ia displaying blueshifted Na I D absorption features than those without blueshifted features, and the strength of the blueshifted Na I D is correlated with the B − V colour of the SN at maximum light. This strongly suggests the absorbing material is local to the SN. In the context of the progenitor systems of SNe Ia, we discuss the significance of these findings and other recent observational evidence on the nature of SN Ia progenitors. We present a summary that suggests that there are at least two distinct populations of normal, cosmologically useful SNe Ia.

An application of bi-directional evolutionary structural optimisation for optimising energy absorbing structures using a material damage model

The Bi-directional Evolutionary Structural Optimisation (BESO) method is a numerical topology optimisation method developed for use in finite element analysis. This paper presents a particular application of the BESO method to optimise the energy absorbing capability of metallic structures. The optimisation objective is to evolve a structural geometry of minimum mass while ensuring that the kinetic energy of an impacting projectile is reduced to a level which prevents perforation. Individual elements in a finite element mesh are deleted when a prescribed damage criterion is exceeded. An energy absorbing structure subjected to projectile impact will fail once the level of damage results in a critical perforation size. It is therefore necessary to constrain an optimisation algorithm from producing such candidate solutions. An algorithm to detect perforation was implemented within a BESO framework which incorporated a ductile material damage model.

Verification of a novel material model to predict damage in composite structures

An intralaminar damage model (IDM), based on continuum damage mechanics, was developed for the simulation of composite structures subjected to damaging loads. This model can capture the complex intralaminar damage mechanisms, accounting for mode interactions, and delaminations. Its development is driven by a requirement for reliable crush simulations to design composite structures with a high specific energy absorption. This IDM was implemented as a user subroutine within the commercial finite element package, Abaqus/Explicit[1]. In this paper, the validation of the IDM is presented using two test cases. Firstly, the IDM is benchmarked against published data for a blunt notched specimen under uniaxial tensile loading, comparing the failure strength as well as showing the damage. Secondly, the crush response of a set of tulip-triggered composite cylinders was obtained experimentally. The crush loading and the associated energy of the specimen is compared with the FE model prediction. These test cases show that the developed IDM is able to capture the structural response with satisfactory accuracy

Material Logistics in Urban Construction Sites: A Structural Equation Model

Aim: The aim of this paper is to identify best practice relating to the effective management of materials in an urban, confined construction site, using structural equation modelling.

Methodology: A literature review, case study analysis and questionnaire survey are employed, with the results scrutinised using confirmatory factor analysis in the form of structural equation modelling.

Results: The following are the leading strategies in the management of materials in a confined urban site environment; (1) Consult and review the project programme, (2) Effective communication and delivery, (3) Implement site safety management plans, and (4) Proactive spatial monitoring and control.

Implication for Practice: With the relentless expansion of urban centres and the increasing high cost of materials, any potential savings made on-site would translate into significant monetary concessions on completion of a development.

Originality/Value: As on-site project management professionals successfully identify and implement the various strategies in the management of plant and materials on a confined urban site, successful resource management in this restrictive environment is attainable.

Innovative Aspect of Paper: An empirical study of three different construction sites in three different countries (Ireland, England and USA) together with a questionnaire survey from the industry, investigating the managerial strategies in the management of plant and material in confined urban site environments

The formal specification of abstract data types and their implementation in Fortran 90: Implementation issues concerning the use of pointers

In this paper we continue our investigation into the development of computational-science software based on the identification and formal specification of Abstract Data Types (ADTs) and their implementation in Fortran 90. In particular, we consider the consequences of using pointers when implementing a formally specified ADT in Fortran 90. Our aim is to highlight the resulting conflict between the goal of information hiding, which is central to the ADT methodology, and the space efficiency of the implementation. We show that the issue of storage recovery cannot be avoided by the ADT user, and present a range of implementations of a simple ADT to illustrate various approaches towards satisfactory storage management. Finally, we propose a set of guidelines for implementing ADTs using pointers in Fortran 90. These guidelines offer a way gracefully to provide disposal operations in Fortran 90. Such an approach is desirable since Fortran 90 does not provide automatic garbage collection which is offered by many object-oriented languages including Eiffel, Java, Smalltalk, and Simula.

A SPECIFICATION OF A COMPLEX PROGRAMMING LANGUAGE STATEMENT

A formal specification of a complex programming language statement is presented. The subject matter was selected as being typical of the kind confronting a small software house. It is shown that formal specification notations may be applied, with benefit, to 'messy' problems. Emphasis is placed upon producing a specification which is readable by, and useful to a reader not familiar with formal notations.

Efficient, Scalable, and Solvent-free Mechanochemical Synthesis of the OLED Material Alq(3) (q=8-Hydroxyquinolinate)

The aluminum complex Alq(3) (q = 8-hydroxyquinolinate), which has important applications in organic light-emitting diode materials, is shown to be readily synthesized as a pure phase under solvent-free mechanochemical conditions from Al(OAc)(2)OH and 8-hydroxyquinoline by ball milling. The initial product of the mechanochemical synthesis is a novel acetic acid solvate of Alq(3), and the alpha polymorph of Alq(3) is obtained on subsequent heating/desolvation of this phase. The structure of the mechanochemically prepared acetic acid solvate of Alq(3) has been determined directly from powder X-ray diffraction data and is shown to be a different polymorph from the corresponding acetic acid solvate prepared by solution-state crystallization of Alq(3) from acetic acid. Significantly, the mechanochemical synthesis of Alq(3) is shown to be fully scalable across two orders of magnitude from 0.5 to 50 g scale. The Alq(3) sample obtained from the solvent-free mechanochemical synthesis is analytically pure and exhibits identical photoluminescence behavior to that of a sample prepared by the conventional synthetic route.