TLC determination of functionality in prepolymers

Application of thin-layer chromatographics provides rapid qualitative determination of functional distribution in experimental prepolymer. Functionality distribution is of fundamental importance for it determines; (1) manner in which given carboxyl-terminated prepolymer will cure and (2) physical properties of resulting product

Glass transition temperatures of liquid prepolymers obtained by thermal penetrometry

Thermal penetrometry is experimental technique for detecting temperature at which frozen prepolymer becomes soft enough to be pierced by weighted penetrometer needle; temperature at which this occurs is called penetration temperature. Apparatus used to obtain penetration temperatures can be set up largely from standard parts

Are There Any Redshift >8 Gamma-Ray Bursts in the BATSE Catalog?

Several luminosity indicators have been found for Gamma-Ray Bursts (GRBs) wherein measurable light curve and spectral properties are well-correlated with the peak luminosity. Several papers have each applied one different luminosity relation to find redshifts for BATSE GRBs and claim to identify specific bursts with z>8. The existence of such high redshift events is not surprising, as BATSE has enough sensitivity to see them and GRBs are expected out to the redshift of the first star formation. To improve results we used five luminosity relations with updated calibrations to determine redshifts with error bars. Combining these relations, we calculated the redshifts of 36 BATSE GRBs with claimed z>8. Our results include 13 bursts with our derived best redshift z_best>8, which looks promising at first. But the calculated redshift uncertainties are significantly large in these selected cases. With only one exception, all of our bursts have z_1siglow<9. The one exception (BATSE trigger 2035) is likely a short duration burst at z>~4. Our best case for a very high redshift event is BATSE trigger 3142 with z_best>20 and z_1siglow=8.9, however we can only say z>4.1 at the two-sigma confidence level. In all, we cannot point toward any one BATSE burst as confidently having z>8. One implication is to greatly weaken prior claims that GRBs have a steeply rising rate-density out to high redshifts.Comment: ApJ in press, 18 page

Saturated hydrocarbon polymeric binder for advanced solid propellant and hybrid solid grains Quarterly report no. 2, 1 Feb. - 30 Apr. 1966

Synthesis and analysis of ethylene-neohexene copolymers with other non ketene-imine group free radicals for solid and hybrid grain propellant saturated hydrocarbon binder progra

Saturated hydrocarbon polymeric binder for advanced solid propellant and hybrid solid grains Quarterly report no. 3, 1 May - 31 Jul. 1966

Saturated hydrocarbon polymeric binder for advanced solid propellant and hybrid solid grain

An MPP version of the Electromagnetism module in LS-DYNA for 3D Coupled Mechanical-Thermal-Electromagnetic simulations

LS-DYNA is a general multi-purpose explicit and implicit finite element program used to analyse the non-linear dynamic response of three-dimensional solids and fluids. It is developed by Livermore Software Technology Corporation (LSTC). A new electromagnetism module is being developed in LS-DYNA for coupled mechanical/thermal/electromagnetic simulations. One of the main applications of this module is Electromagnetic Metal Forming (EMF). The electromagnetic fields are solved using a Finite Element Method (FEM) for the conductors coupled with a Boundary Element Method (BEM) for the surrounding air/insulators. Both methods use elements based on discrete differential forms for improved accuracy. Recently, a Massively Parallel Processing (MPP) version of the EM module was developed allowing sharing the CPU and memory between different processors and thus faster computations on larger problems. The implementation of the FEM and BEM in MPP will be presented. Finally, the EM module will be illustrated on an actual EMF case. Experimental and numerical results will be compared and the speed-up of the MPP version will be studied

Has the credit default swap market lowered the cost of corporate debt?

There have been widespread claims that credit derivatives such as the credit default swap (CDS) have lowered the cost of firms’ debt financing by creating for investors new hedging opportunities and information. However, these instruments also give banks an opaque means to sever links to their borrowers, thus reducing lender incentives to screen and monitor. In this paper, we evaluate the effect that the onset of CDS trading has on the spreads that underlying firms pay at issue when they seek funding in the corporate bond and syndicated loan markets. Employing matched-sample methods, we find no evidence that the onset of CDS trading affects the cost of debt financing for the average borrower. However, we do find economically significant adverse effects to risky and informationally-opaque firms. It appears that the onset of CDS trading reduces the effectiveness of the lead bank’s retained share in resolving any asymmetric information problems that exist between a lead bank and non-lead participants in a loan syndicate. On the plus side, we do find that CDS trading has a small positive effect on spreads at issue for transparent and safe firms, in which the lead bank’s share is much less important. Moreover, we document that the benefit of CDS trading on spreads increases once the market becomes sufficiently liquid. In sum, while CDS trading has contributed to the completeness of markets, it has also created new problems by reducing the effectiveness of lead banks’ loan shares as a monitoring device—thus creating a need for regulatory intervention

Introduction of an Electromagnetism Module in LS-DYNA for Coupled Mechanical Thermal Electromagnetic Simulations

A new electromagnetism module is being developed in LS-DYNA for coupled mechanical/thermal/electromagnetic simulations. One of the main applications of this module is Electromagnetic Metal Forming. The electromagnetic fields are solved using a Finite Element Method for the conductors coupled with a Boundary Element Method for the surrounding air/insulators. Both methods use elements based on discrete differential forms for improved accuracy. The physics, numerical methods and capabilities of this new module are presented in detail as well as its coupling with the mechanical and thermal solvers of LS-DYNA. This module is then illustrated on an Electromagnetic Metal Forming case

Acting out our dam future: science-based role-play simulations as mechanisms for learning and natural resource planning

Science often does not make its way into decisions, leading to a problematic gap between scientific and societal progress. To tackle this issue, our research tests a novel science-based negotiation simulation that integrates a role-play simulation (RPS) with a system dynamics model (SDM). In RPSs, stakeholders engage in a mock decision-making process (reflecting real-life institutional arrangements and scientific knowledge) for a set period. System dynamics models (SDMs) are visual tools used to simulate the interactions and feedback within a complex system. We test the integration of the two approaches with stakeholders in New England via a series of two consecutive workshops across two states. The workshops engage stakeholders from diverse groups to foster dialogue, learning, and creativity. Participants discuss a hypothetical (yet realistic) decision scenario to consider scientific information and explore dam management options that meet one another\u27s interests. In the first workshop, participants contributed to the design of the fictionalized dam decision scenario and the SDM. In the second workshop, participants assumed another representative\u27s role and discussed dam management options for the fictionalized scenario. This presentation will briefly report on the practical design of this science-based role-play, and particularly emphasize preliminary results of workshop outcomes, which were evaluated using debriefing sessions, surveys, concept mapping exercises, and interviews. Results will determine the extent to which this new knowledge production process leads to learning, use of science, and more collaborative decision-making about dams in New England and beyond