Fuels characterization studies

Current analytical techniques used in the characterization of broadened properties fuels are briefly described. Included are liquid chromatography, gas chromatography, and nuclear magnetic resonance spectroscopy. High performance liquid chromatographic ground-type methods development is being approached from several directions, including aromatic fraction standards development and the elimination of standards through removal or partial removal of the alkene and aromatic fractions or through the use of whole fuel refractive index values. More sensitive methods for alkene determinations using an ultraviolet-visible detector are also being pursued. Some of the more successful gas chromatographic physical property determinations for petroleum derived fuels are the distillation curve (simulated distillation), heat of combustion, hydrogen content, API gravity, viscosity, flash point, and (to a lesser extent) freezing point

Ultra-Lightweight Self-Deployable Nanocomposite Structure for Habitat Applications

A document discusses self-deployable, rigidized structures that are ultra-lightweight and have gas barrier properties, space durability, and high impact resistance. Developed here are microcellular-foamed sandwich structures made from nanocomposite shape memory polymers (SMPs) with Cold-Hibernated Elastic Memory (CHEM) deployed technique for space structural components including space habitats. This type of foam sandwich also does not suffer from the toxicity problems of conventional foams, and has higher mechanical properties than those processed with conventional techniques. This design can be compacted into a very small volume for launch. Once deployed, the microcellular structure can use the heat from the Sun to recover 98 to 100 percent of its shape

Research on aviation fuel instability

The underlying causes of fuel thermal degradation are discussed. Topics covered include: nature of fuel instability and its temperature dependence, methods of measuring the instability, chemical mechanisms involved in deposit formation, and instrumental methods for characterizing fuel deposits. Finally, some preliminary thoughts on design approaches for minimizing the effects of lowered thermal stability are briefly discussed

Detailed investigation of a vaporising fuel spray. Part 1: Experimental investigation of time averaged spray

A laser tomographic light scattering technique provides rapid and accurate high resolution measurements of droplet sizes, concentrations, and vaporization. Measurements using a computer interfaced thermocouple are presented and it is found that the potential exists for separating gas and liquid temperature measurements and diagnosing local spray density by in situ analysis of the response characteristics of the thermocouple. The thermocouple technique provides a convenient means for measuring mean gas velocity in both hot and cold two phase flows. The experimental spray is axisymmetric and has carefully controlled initial and boundary conditions. The flow is designed to give relatively insignificant transfer of momentum and mass from spray to air flow. The effects of (1) size-dependent droplet dispersion by the turbulence, (2) the initial spatial segregation of droplet sizes during atomization, and (3) the interaction between droplets and coherent large eddies are diagnosed

Quantum Dot in 2D Topological Insulator: The Two-channel Kondo Fixed Point

In this work, a quantum dot couples to two helical edge states of a 2D topological insulator through weak tunnelings is studied. We show that if the electron interactions on the edge states are repulsive, with Luttinger liquid parameter $K < 1$, the system flows to a stable two-channel fixed point at low temperatures. This is in contrast to the case of a quantum dot couples to two Luttinger liquid leads. In the latter case, a strong electron-electron repulsion is needed, with $K<1/2$, to reach the two-channel fixed point. This two-channel fixed point is described by a boundary Sine-Gordon Hamiltonian with a $K$ dependent boundary term. The impurity entropy at zero temperature is shown to be $\ln\sqrt{2K}$. The impurity specific heat is $C \propto T^{\frac{2}{K}-2}$ when $2/3 < K < 1$, and $C \propto T$ when $K<2/3$. We also show that the linear conductance across the two helical edges has non-trivial temperature dependence as a result of the renormalization group flow.Comment: 4+\epsilon page

Capabilities-strategy match and board governance: their impacts on financial performance and accountability-emphasis of government business enterprises

The study addresses three research questions posed by the nature of government business enterprises. The three questions are (1) Does the way management (including the board) aligns the development of GBE organisational capabilities and the formulation of strategies have an influence on the financial performance and management&#039;s emphasis for discharging accountability requirements of that GBE? (2) Does the extent of adoption of board governance structures have an influence on financial performance and accountability-emphasis given by management of a GBE? (3) Does board composition moderate the relationship between capabilities-strategy configurations and performance of a GBE? The research questions are addressed as follow. First, the study explores the concepts of corporate governance, board governance in particular, strategy, capabilities and accountability in the context of GBEs. Second, the study investigates relationships between GBEs&#039; governance arrangements and performance, on the one hand, and capabilities-strategy match and performance on the other hand. The concept of performance used in this study is separated into financial performance, measured by economic rate of return (ERR) (a government-developed algorithm for GBEs comprising financial accounting and market measures), and accountability-emphasis (ACCBTY) (management&#039;s attention to systems and processes used for discharging aspects of accountability). Third, the study investigates the moderating effects of GBEs&#039; board governance arrangements on the relationship between capabilities-strategy match and performance. The findings of the study are as follow. First, the results of a set of multivariate analyses indicate that board governance index (BGI) has a positive and significant relationship with ERR, but has no significant relationship with ACCBTY. At the individual governance mechanism level, the percentages of non-executive directors (NEDs), politically-related directors (PRDs) and financial-literate directors (FLDs) are all strongly and positively related to ERR. These findings are supported by certain prior studies from different contexts. On the ACCBTY side, these specific board governance variables are not found to support a hypothesis that the composition of the board will impact on the GBE&#039;s attention to accountability processes. Second, the findings indicate that capabilities-strategy match (CSM) has no significant influence on ERR but has a strong and positive impact on ACCBTY. The results indicate that only the alignment between defender strategic-type and outside-in capabilities has a positive relationship with both ERR and ACCBTY. Other than the defender strategic position, alternative strategy-types will align with capabilities (e.g. prospector strategy and inside-out capabilities) to have a significant positive affect on ACCBTY, but not on ERR. Third, the study finds that GBE&#039;s board governance arrangements (BGI) have a positive moderating affect on the relationship between capabilities-strategy match and ERR. However, BGI has no moderating impact on capabilities-strategy match and ACCBTY relationship. The findings draw the conclusion that in order to achieve their dual objectives of concurrently fulfilling financial performance and accountability-emphasis, GBEs need to adopt a defender strategic-type, develop strengths in outside-in capabilities and have their boards of directors comprise of non-executive directors, politically-linked directors and financial-literate directors. Given the limitations underlying the findings that are mentioned, the conclusion from this study has implications for government-owners and managers of GBE

Electrically pumped semiconductor laser with low spatial coherence and directional emission

We design and fabricate an on-chip laser source that produces a directional beam with low spatial coherence. The lasing modes are based on the axial orbit in a stable cavity and have good directionality. To reduce the spatial coherence of emission, the number of transverse lasing modes is maximized by fine-tuning the cavity geometry. Decoherence is reached in a few nanoseconds. Such rapid decoherence will facilitate applications in ultrafast speckle-free full-field imaging

Aspects of Symmetry in de Sitter Space

We study various aspects of symmetry in four-dimensional de Sitter space (dS$_4$).Physic

Graphic Presentation: An Empirical Examination of the Graphic Novel Approach to Communicate Business Concepts

Graphic novels have been increasingly incorporated into business communication forums. Despite potential benefits, little research has examined the merits of the graphic novel approach. In response, we engage in a two-study approach. Study 1 explores the potential of graphic novels to affect learning outcomes and finds that the graphic novel was related to high levels of learning experiences. Study 2 compares the impact of graphic novels with that of traditional textbooks and finds that verbatim recognition was superior with graphic novel texts. Overall, we provide the first comprehensive examination of the graphic novel as a tool for effective business communication.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline