The chemical structure and mechanical properties of phenolic resins and related polymers

Paper-based phenolic laminates are used extensively in the electrical industry. Many small components are fabricated from these materials by the process known as punching. Recently an investigation was carried out to study the effect of processing variables on the punching properties. It was concluded that further work would be justified and that this should include a critical examination of the resin properties in a more controlled and systematic manner. In this investigation an attempt has been made to assess certain features of the resin structure in terms of thermomechanical properties. The number of crosslinks in the system was controlled using resins based on phenol and para-cresol formulations. Intramolecular hydrogen bonding effects were examined using substituted resins and a synthetically derived phenol based on 1,3-di-(o-hydroxyphenyl) propane.. A resin system was developed using the Friedel Crafts reaction to examine inter-molecular hydrogen bonding at the resin-paper interface. The punching properties of certain selected resins were assessed on a qualitative basis. In addition flexural and dynamic mechanical properties were determined in a general study of the structure-property relationships of these materials. It has been shown that certain features of the resin structure significantly influenced mechanical properties. :F'urther, it was noted that there is a close relationship between punching properties, mechanical damping and flexural strain. This work includes a critical examination of the curing mechanism and views are postulated in an attempt to extend knowledge in this area of the work. Finally, it is argued that future work should be based on a synthetic approach and that dynamic mechanical testing would provide a powerful tool In developing a deeper understanding of the resin fine structure.

Control of soundness and mechanical properties in aluminium-silicon-magnesium alloys

Previously, specifications for mechanical properties of casting alloys were based on separately cast test bars. This practice provided consistently reproducible results; thus, any change in conditions was reflected in changes in the mechanical properties of the test coupons. These test specimens, however, did not necessarily reflect the actual mechanical properties of the castings they were supposed to represent'. Factors such as section thickness and casting configuration affect the solidification rate and soundness of the casting thereby raising or lowering its mechanical properties in comparison with separately cast test specimens. In the work now reported, casting shapes were developed to investigate the variations of section thickness, chemical analysis and heat treatment on the mechanical properties of a high strength Aluminium alloy under varying chilling conditions. In addition, an insight was sought into the behaviour of chills under more practical conditions. Finally, it was demonstrated that additional information could be derived from the radiographs which form an essential part of the quality control of premium quality castings. As a result of the work, it is now possible to select analysis and chilling conditions to optimize the as cast and the heat treated mechanical properties of Aluminum 7% Silicon 0.3% Magnesium alloy.

An examination of the production, heat treatment and mechanical properties of a new wrought magnesium alloy containing 6% Zn. and 1.2% Mn.

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State subsidy and moral hazard in corporate financing

This paper investigates the impact of state subsidy on the behavior of the entrepreneur under asymmetric information. Several authors formulated concerns about state intervention as it can aggravate moral hazard in corporate financing. In the seminal paper of Holmström and Tirole (1997) a two-player moral hazard model is presented with an entrepreneur initiating a risky scalable project and a private investor (e.g. bank or venture capitalist) providing outside financing. The novelty of our research is that this basic moral hazard model is extended to the case of positive externalities and to three players by introducing the state subsidizing the project. It is shown that in the optimum, state subsidy does not harm, but improves the incentives of the entrepreneur to make efforts for the success of the project; hence in effect state intervention reduces moral hazard. Consequently, state subsidy increases social welfare which is defined as the sum of private and public net benefits. Also, the exact form of the state subsidy (ex-ante/ex-post, conditional/unconditional, refundable/nonrefundable) is irrelevant in respect of the optimal size and the total welfare effect of the project. Moreover, in case of nonrefundable subsidies state does not crowd out private investors; but on the contrary, by providing additional capital it boosts private financing. In case of refundable subsidies some crowding effects may occur depending on the subsidy form and the parameters.

Exploring thermal and mechanical properties of selected transition elements under extreme conditions: Experiments at high pressures and high temperatures

Transition metals (Ti, Zr, Hf, Mo, W, V, Nb, Ta, Pd, Pt, Cu, Ag, and Au) are essential building units of many materials and have important industrial applications. Therefore, it is important to understand their thermal and physical behavior when they are subjected to extreme conditions of pressure and temperature. This dissertation presents: • An improved experimental technique to use lasers for the measurement of thermal conductivity of materials under conditions of very high pressure (P, up to 50 GPa) and temperature (T up to 2500 K). • An experimental study of the phase relationship and physical properties of selected transition metals, which revealed new and unexpected physical effects of thermal conductivity in Zr, and Hf under high P-T. • New phase diagrams created for Hf, Ti and Zr from experimental data. • P-T dependence of the lattice parameters in α-hafnium. Contrary to prior reports, the α-ω phase transition in hafnium has a negative dT/dP slope. • New data on thermodynamic and physical properties of several transition metals and their respective high P-T phase diagrams. • First complete thermodynamic database for solid phases of 13 common transition metals was created. This database has: All the thermochemical data on these elements in their standard state (mostly available and compiled); All the equations of state (EoS) formulated from pressure-volume-temperature data (measured as a part of this study and from literature); Complete thermodynamic data for selected elements from standard to extreme conditions. The thermodynamic database provided by this study can be used with available thermodynamic software to calculate all thermophysical properties and phase diagrams at high P-T conditions. For readers who do not have access to this software, tabulated values of all thermodynamic and volume data for the 13 metals at high P-T are included in the APPENDIX. In the APPENDIX, a description of several other high-pressure studies of selected oxide systems is also included. Thermophysical properties (Cp, H, S, G) of the high P-T ω-phase of Ti, Zr and Hf were determined during the optimization of the EoS parameters and are presented in this study for the first time. These results should have important implications in understanding hexagonal-close-packed to simple-hexagonal phase transitions in transition metals and other materials.

Participative Budgeting and Participant Motivation: A Review of the Literature

In their discussion - Participative Budgeting and Participant Motivation: A Review of the Literature - by Frederick J. Demicco, Assistant Professor, School of Hotel, Restaurant and Institutional Management, The Pennsylvania State University and Steven J. Dempsey, Fulton F. Galer, Martin Baker, Graduate Assistants, College of Business at Virginia Polytechnic Institute and State University, the authors initially observe: “In recent years behavioral literature has stressed the importance of participation In goal-setting by those most directly affected by those goals. The common postulate is that greater participation by employees in the various management functions, especially the planning function, will lead to improved motivation, performance, coordination, and functional behavior. The authors analyze this postulate as it relates to the budgeting process and discuss whether or not participative budgeting has a significant positive impact on the motivations of budget participants.” In defining the concept of budgeting, the authors offer: “Budgeting is usually viewed as encompassing the preparation and adoption of a detailed financial operating plan…” In furthering that statement they also furnish that budgeting’s focus is to influence, in a positive way, how managers plan and coordinate the activities of a property in a way that will enhance their own performance. In essence, framing an organization within its described boundaries, and realizing its established goals. The authors will have you know, to control budget is to control operations. What kind of parallels can be drawn between the technical methods and procedures of budgeting, and managerial behavior? “In an effort to answer this question, Ronen and Livingstone have suggested that a fourth objective of budgeting exists, that of motivation,” say the authors with attribution. “The managerial function of motivation is manipulative in nature.” Demicco, Dempsey, Galer, and Baker attempt to quantify motivation as a psychological premise using the expectancy theory, which encompasses empirical support, intuitive appeal, and ease of application to the budgetary process. They also present you with House's Path-Goal model; essentially a mathematics type formula designed to gauge motivation. You really need to see this. The views of Argyris are also explored in particular detail. Although, the Argyris study was primarily aimed at manufacturing firms, and the effects on line-supervisors of the manufacturing budgets which were used to control and evaluate their performance, its application is relevant to the hospitality industry. As the title suggests, other notables in the field of behavioral motivation theory, and participation are also referenced. “Behavioral theory has been moving away from models of purported general applicability toward contingency models that are suited for particular situations,” say the authors in closing. “It is conceivable that some time in the future, contingency models will make possible the tailoring of budget strategies to individual budget holder personalities.”