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WR 10 Millimeter Wave Microcalorimeter

Description: Abstract: A microcalorimeter has been built in WR 10 waveguide, 75-110 GHz, to serve as a power standard at the National Bureau of Standards (NBS). Included here is an evaluation of the errors in using the microcalorimeter for the measurement of effective efficiency of bolometer mounts. The error analysis shows a systematic uncertainty of +/- .83 percent and a random uncertainty of .37 percent.
Date: June 1981
Creator: Weidman, Manly P. & Hudson, Paul A.
Partner: UNT Libraries Government Documents Department

WR15 Microwave Calorimeter and Bolometer Unit

Description: Descriptions of the principal changes in the calorimeter and bolometer unit from the WR28 models of a microwave serving as National Bureau of Standards standard for power measurements in the frequency range 50 to 75 GHz.
Date: May 1972
Creator: Harvey, Morris E.
Partner: UNT Libraries Government Documents Department

Heat of Reaction of Chlorine Trifluoride with Water

Description: Abstract: "A measurement of the heat liberated when chlorine trifluoride reacts with water has been made in a simple Dewar calorimeter. The chlorine trifluoride vapor was bubbled into approximately 20 moles of water; the weight of material used, heat equivalent of the calorimeter, and the temperature rise of the water and calorimeter were determined. From these data an average value for the heat of reaction was calculated to be 81.0 +/- 0.4 kcal/mole. Analysis of the reaction solution and evolved gas showed the following to be present: hydrogen fluoride, hydrogen chloride, chlorine, oxygen, and probably oxygen-chlorine compounds."
Date: October 24, 1950
Creator: Oliver, G. D. & Grisard, J. W.
Partner: UNT Libraries Government Documents Department

Energy flow in a hadronic cascade: Application to hadroncalorimetry

Description: The hadronic cascade description developed in an earlierpaper is extended to the response of an idealized fine-sampling hadroncalorimeter. Calorimeter response is largely determined by the transferof energy E_e from the hadronic to the electromagnetic sector via \pi0production. Fluctuations in this quantity produce the "constant term" inhadron calorimeter resolution. The increase of its fractional mean, f_\rmem^0= \vevE_e/E, with increasing incident energy E causes the energydependence of the \pi/e ratio in a noncompensating calorimeter. The meanhadronic energy fraction, f_h0 = 1-f_\rm em0, was shown to scaleverynearly as a power law in E: f_h0 = (E/E_0)m-1, where E_0\approx1~;GeV forpions, and m\approx0.83. It follows that \pi/e=1-(1-h/e)(E/E_0)m-1, whereelectromagnetic and hadronic energy deposits are detected withefficiencies e and h, respectively. Fluctuations in these quantities,along with sampling fluctuations, are in corporated to give an overallunderstanding of resolution, which is different from the usual treatmentsin interesting ways. The conceptual framework is also extended to theresponse to jets and the difference between pi and presponse.
Date: May 17, 2006
Creator: Groom, Donald E.
Partner: UNT Libraries Government Documents Department

Absolute beam flux measurement at NDCX-I using gold-melting calorimetry technique

Description: We report on an alternative way to measure the absolute beam flux at the NDCX-I, LBNL linear accelerator. Up to date, the beam flux is determined from the analysis of the beam-induced optical emission from a ceramic scintilator (Al-Si). The new approach is based on calorimetric technique, where energy flux is deduced from the melting dynamics of a gold foil. We estimate an average 260 kW/cm2 beam flux over 5 {micro}s, which is consistent with values provided by the other methods. Described technique can be applied to various ion species and energies.
Date: April 1, 2011
Creator: Ni, P. A.; Bieniosek, F. M.; Lidia, S. M. & Welch, J.
Partner: UNT Libraries Government Documents Department

Enthalpies of solution and enthalpies of solvation of organic solutes in ethylene glycol at 298.15 K: prediction and analysis of intermolecular interaction contributions

Description: This article studies thermochemistry of solvation of inert gases and organic solutes in ethylene glycol was thoroughly studied using solution calorimetry technique.
Date: December 24, 2016
Creator: Stolov, Mikhail; Zaitseva, Ksenia V.; Varfolomeev, Mikhail A. & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

Reversible Guest Exchange Mechanisms in Supramolecular Host-Guest Assemblies

Description: Synthetic chemists have provided a wide array of supramolecular assemblies able to encapsulate guest molecules. The scope of this tutorial review focuses on supramolecular host molecules capable of reversibly encapsulating polyatomic guests. Much work has been done to determine the mechanism of guest encapsulation and guest release. This review covers common methods of monitoring and characterizing guest exchange such as NMR, UV-VIS, mass spectroscopy, electrochemistry, and calorimetry and also presents representative examples of guest exchange mechanisms. The guest exchange mechanisms of hemicarcerands, cucurbiturils, hydrogen-bonded assemblies, and metal-ligand assemblies are discussed. Special attention is given to systems which exhibit constrictive binding, a motif common in supramolecular guest exchange systems.
Date: September 1, 2006
Creator: Pluth, Michael D. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department

Proceedings of the Workshop on Techniques for Measurement of Thermodynamic Properties, Albany, Oregon, August 21-23, 1979

Description: Report issued by the U.S. Bureau of Mines discussing a workshop held on the techniques for measurement of thermodynamic properties. As stated in the abstract, "this information circular comprises the proceedings of the workshop and includes the texts of papers presented and discussion by attendees" (p. 1). This report includes tables, illustrations, and photographs.
Date: 1981
Creator: Gokcen, N. A.; Mrazek, R. V. & Pankratz, L. B.
Partner: UNT Libraries Government Documents Department

Test and Evaluation of the Argonne BPAC10 Series Air Chamber Calorimeter Designed for 20 Minute Measurements

Description: This paper is the final report on DOE-OSS Task ANLE88002 Fast Air Chamber Calorimetry.'' The task objective was to design, construct, and test an isothermal air chamber calorimeter for plutonium assay of bulk samples that would meet the following requirements for sample power measurement: average sample measurement time less than 20 minutes. Measurement of samples with power output up to 10 W. Precision of better than 1% RSD for sample power greater than 1 W. Precision better than 0.010 watt SD, for sample power less than 1 W. This report gives a description of the calorimeter hardware and software and discusses the test results. The instrument operating procedure, included as an appendix, gives examples of typical input/output and explains the menu driven software.
Date: October 1990
Creator: Perry, R. B.; Fiarman, Sidney; Jung, Erwin A. & Cremers, Teresa
Partner: UNT Libraries Government Documents Department

Heats of Solution of the Cobaltous Nitrate Hydrates in Water and in Certain Organic Solvents and Binding Energies of Molecular Ligands

Description: Abstract: "Heats of solution have been measured for the hexahydrate, tetrahydrate, trihydrate and dihydrate of cobaltus nitrate in water and in a series of organic solvents, including isobutyl alcohol, diethyland monoethyl ether of ethylene glycol, acetone, methyl ethyl ketone, tetrahydrofuran, tributyl phosphate and dimethyl formanide. For some solvents, where the solubility of the salt of its reaction product was insufficient, measurements were made in a mixture with acetone. Such solvents include diethyl ether, tetrahydrofurfuryl alcohol, and pyridine. Measurements were also made with mixtures of the other solvents cited and acetone. In the cases of pyridine, water, tetrahydrofurfuryl alcohol and isobutyl alcohol, evidence is found for a transition from a probably tetrasolvated neutral molecule in solution to a hexasolvated entity, frequently of lowered solubility. The solvents can be arrayed in order of base strengths on the basis of the heat measurements, and it is possible to estimate energies of binding of solvent groups by the metal atom. As a check on these some measurements of the heats of solution of some cobaltous nitrate pyridinates are also presented."
Date: February 1952
Creator: Katzin, Leonard I. & Ferraro, John R., {}
Partner: UNT Libraries Government Documents Department

First calorimetric determination of heat of extraction of 248Cm in a bi-phasic system

Description: This report presents a summary of the work performed to meet FCR&D level 2 milestone M21SW050201, 'Complete the first calorimetric determination of heat of extraction of 248Cm in a bi-phasic system'. This work was carried out under the auspices of the Thermodynamics and Kinetics FCR&D work package. To complement previous work undertaken under this work package we have extended out heat of extraction studies by di-2-ethyl-hexyl-phosphoric acid to curium. This report also details the heat of extraction of samarium in the same system. This work was performed to not only test the methodology but also to check for consistency with the heats of extraction obtained with those in the prior literature. The heat of extraction for samarium that was obtained in this study was -9.6 kJ mol-1, which is in reasonable agreement with the previously obtained value of -10.9 kJ mol-1. The curium heat of extraction was performed under two sets of conditions and the obtained heats of extraction were in reasonable agreement with each other at -16.0 {+-} 1.1 and -16.8 {+-} 1.5 kJ mol-1.
Date: June 1, 2011
Creator: Martin, Leigh R. & Zalupski, Peter R.
Partner: UNT Libraries Government Documents Department

A simplistic view of hadron calorimetry

Description: All too often we rely on Monte Carlo simulations withoutworrying too much about basic physics. It is possible to start with avery simple calorimeter (a big cylinder) and learn the functional form ofpi e by aninduction argument. Monte Carlo simulations provide sanitychecks and constants. A power-law functional form describes test beamresults surprisingly well. The prediction that calorimeters responddifferently to protons and pions of the same energy was unexpected. Theeffect was later demonstrated by the CMS forward calorimeter group, usingthe most noncompensating calorimeter ever built. Calorimeter resolutionis dominated by fluctuations in piz production and the energy deposit byneutrons. The DREAM collaboration has recently used a dual readoutcalorimeter to eliminate the first of these. Ultimate resolution dependson measuring neutrons on an event-by-event basis as well.
Date: November 16, 2006
Creator: Groom, Donald E.
Partner: UNT Libraries Government Documents Department

Synergies between electromagnetic calorimetry and PET

Description: The instrumentation used for the nuclear medical imaging technique of Positron Emission Tomography (PET) shares many features with the instrumentation used for electromagnetic calorimetry. Both fields can certainly benefit from technical advances in many common areas, and this paper discusses both the commonalties and the differences between the instrumentation needs for the two fields. The overall aim is to identify where synergistic development opportunities exist. While such opportunities exist in inorganic scintillators, photodetectors, amplification and readout electronics, and high-speed computing, it is important to recognize that while the requirements of the two fields are similar, they are not identical, and so it is unlikely that advances specific to one field can be transferred without modification to the other.
Date: July 30, 2002
Creator: Moses, William W.
Partner: UNT Libraries Government Documents Department

External and Internal Guest Binding of a Highly Charged Supramolecular Host in Water: Deconvoluting the Very Different Thermodynamics

Description: NMR, UV-vis and isothermal titration calorimetry (ITC) measurements probe different aspects of competing host-guest equilibria as simple alkylammonium guest molecules interact with both the exterior (ion-association) and interior (encapsulation) of the [Ga{sub 4}L{sub 6}]{sup 12-} supramolecular assembly in water. Data obtained by each independent technique measure different components of the host-guest equilibria and only when analyzed together does a complete picture of the solution thermodynamics emerge. Striking differences between the internal and external guest binding are found. External binding is enthalpy driven and mainly due to attractive interactions between the guests and the exterior surface of the assembly while encapsulation is entropy driven as a result of desolvation and release of solvent molecules from the host cavity.
Date: July 22, 2009
Creator: Sgarlata, Carmelo; Mugridge, Jeffrey; Pluth, Michael; Tiedemann,, Bryan; Zito, Valeria; Arena, Giuseppe et al.
Partner: UNT Libraries Government Documents Department

Ionic liquids for rechargeable lithium batteries

Description: We have investigated possible anticipated advantages of ionic-liquid electrolytes for use in lithium-ion batteries. Thermal stabilities and phase behavior were studied by thermal gravimetric analysis and differential scanning calorimetry. The ionic liquids studied include various imidazoliumTFSI systems, pyrrolidiniumTFSI, BMIMPF{sub 6}, BMIMBF{sub 4}, and BMIMTf. Thermal stabilities were measured for neat ionic liquids and for BMIMBF{sub 4}-LiBF{sub 4}, BMIMTf-LiTf, BMIMTFSI-LiTFSI mixtures. Conductivities have been measured for various ionic-liquid lithium-salt systems. We show the development of interfacial impedance in a Li|BMIMBF{sub 4} + LiBF{sub 4}|Li cell and we report results from cycling experiments for a Li|BMIMBF{sub 4} + 1 mol/kg LIBF{sub 4}|C cell. The interfacial resistance increases with time and the ionic liquid reacts with the lithium electrode. As expected, imidazolium-based ionic liquids react with lithium electrodes. We seek new ionic liquids that have better chemical stabilities.
Date: September 29, 2005
Creator: Salminen, Justin; Papaiconomou, Nicolas; Kerr, John; Prausnitz,John & Newman, John
Partner: UNT Libraries Government Documents Department

ISOTHERMAL (DELTA)/(ALPHA-PRIME) TRANSFORMATION AND TTT DIAGRAM IN A PLUTONIUM GALLIUM ALLOY

Description: Differential scanning calorimetry (DSC) is used as an alternative approach to determining the tine-temperature-transformation (TTT) diagram for the martensitic delta to alpha-prime transformation in a Pu-2.0 at% Ga alloy. Previous work suggests that the TTT diagram for a similar alloy exhibits an unusual double-C curve for isothermal holds of less than 100 minutes. Here, we extend this diagram to 18 hours, and confirm the double-C curve behavior. When the sample is cooled prior to the isothermal holds, the delta to alpha-prime transformation is observed as several overlapping exothermic peaks. These peaks are very reproducible, and they are believed to be the result of different kinds of delta to alpha-prime martensitic transformation. This may be due to the presence of different nucleation sites and/or different morphologies.
Date: November 11, 2005
Creator: Oudot, B P; Blobaum, K M; Wall, M A & Schwartz, A J
Partner: UNT Libraries Government Documents Department

DSWA calorimeter bomb experiments

Description: Two experiments were performed in which 25 grams of TNT were detonated inside an expended detonation calorimeter bomb. The bomb had a contained volume of approximately 5.28 liters. In the first experiment, the bomb was charged with 3 atmospheres of nitrogen. In the second, it was charged with 2.58 atmospheres (23.1 psi gage) of oxygen. In each experiment pressure was monitored over a period of approximately 1200 microseconds after the pulse to the CDU. Monitoring was performed via two 10,000 psi 102AO3 PCB high frequency pressure transducers mounted symmetrically in the lid of the calorimeter bomb. Conditioners used were PCB 482As. The signals from the transducers were recorded in digital format on a multi channel Tektronix scope. The sampling frequency was 10 Mhz (10 samples per microsecond). After a period of cooling following detonation, gas samples were taken and were subsequently submitted for analysis using gas mass spectrometry. Due to a late request for post shot measurement, it was only possible to make a rough estimate of the weight of debris (carbon) remaining in the calorimeter bomb following the second experiment.
Date: October 1, 1998
Creator: Cunningham, B
Partner: UNT Libraries Government Documents Department

The FB-Line and F-Canyon HAN/Nitric Acid Decomposition Study

Description: Separations requested SRTC study the autocatalytic decomposition of the hydroxylamine nitrate which may occur in the presence of concentrated nitric acid with respect to making-up cold feed solutions. The data obtained from this study will provide Separations an envelope within which safe operations can be conducted.
Date: August 19, 1998
Creator: Hang, T.
Partner: UNT Libraries Government Documents Department