Vaporisation and thermal decomposition of dialkylimidazolium halide ion ionic liquids.
Lovelock, Kevin R J; Armstrong, James P; Licence, Peter; Jones, Robert G
2014-01-28
Vaporisation and liquid phase thermal decomposition, TD, of two halide ion ionic liquids, 1-octyl-3-methylimidazolium chloride, [C8C1Im]Cl, and 1-octyl-3-methylimidazolium iodide, [C8C1Im]I, are investigated using temperature programmed desorption (TPD) line of sight mass spectrometry (LOSMS) at ultra-high vacuum (UHV). The ability to use MS to distinguish between vaporisation and TD allows the thermodynamics/kinetics of both vaporisation and TD to be investigated within the same experiments. Vaporisation of both halide ion ionic liquids is demonstrated. For both [C8C1Im]Cl and [C8C1Im]I the vapour is shown to be composed of neutral ion pairs (NIPs). The enthalpy of vaporisation at temperature T, ΔvapHT, was experimentally determined as ΔvapH455 = 151 ± 10 kJ mol(-1) for [C8C1Im]Cl and ΔvapH480 = 149 ± 8 kJ mol(-1) for [C8C1Im]I. Extrapolation of ΔvapHT to the reference temperature, 298 K, gave ΔvapH298 = 166 ± 10 kJ mol(-1) for [C8C1Im]Cl and ΔvapH298 = 167 ± 8 kJ mol(-1) for [C8C1Im]I, higher than most ΔvapH298 values measured to date for other [C8C1Im](+)-containing ionic liquids. In addition, predictions of ΔvapH298 for other halide ion ionic liquids are made. Liquid phase TD is shown to proceed via nucleophilic substitution to give two sets of products: 1-octylimidazole and methylhalide, and 1-methylimidazole and 1-octylhalide. The activation energy of TD at a temperature T, Ea,TD,T, is measured for the nucleophilic substitution of [C8C1Im]I to give methyliodide; Ea,TD,480 = 136 ± 15 kJ mol(-1). Ea,TD,T is measured for the nucleophilic substitution of [C8C1Im]Cl to give methylchloride; Ea,TD,455 = 132 ± 10 kJ mol(-1). The fact that ΔvapHT and Ea,TD,T are the same (within error) for both ionic liquids is commented upon, and conclusions are drawn as to the thermal stability of these ionic liquids.
Ionic liquids: dissecting the enthalpies of vaporization.
Köddermann, Thorsten; Paschek, Dietmar; Ludwig, Ralf
2008-03-14
We calculate the heats of vaporisation for imidazolium-based ionic liquids [C(n)mim][NTf(2)] with n=1, 2, 4, 6, 8 by means of molecular dynamics (MD) simulations and discuss their behavior with respect to temperature and the alkyl chain length. We use a force field developed recently. The different cohesive energies contributing to the overall heats of vaporisations are discussed in detail. With increasing alkyl chain length, the Coulomb contribution to the heat of vaporisation remains constant at around 80 kJ mol(-1), whereas the van der Waals interaction increases continuously. The calculated increase of about 4.7 kJ mol(-1) per CH(2)-group of the van der Waals contribution in the ionic liquid exactly coincides with the increase in the heats of vaporisation for n-alcohols and n-alkanes, respectively. The results support the importance of van der Waals interactions even in systems completely composed of ions.
Enthalpy of phase transitions of lactams
NASA Astrophysics Data System (ADS)
Emel'yanenko, V. N.; Verevkin, S. P.; Ralys, R. V.; Turovtsev, V. V.; Orlov, V. Yu.
2012-10-01
The transpiration method is used to measure the temperature dependences of the vapors pressures of azacyclobutan-2-one (I, CAS 930-21-2) azacyclohexan-2-one (II, CAS 675-20-7); azacyclooctan-2-one (III, CAS 673-66-5); azacyclononan-2-one (IV, CAS 935-30-8) and azacyclotridecan-2-one (V, CAS 947-04-6). Enthalpies of sublimation and vaporisation are determined. The temperatures and enthalpies of fusion of compounds (I, III-V) are found by means of differential scanning calorimetry. The dependences of the enthalpies of vaporisation of lactones, lactams, cycloalkanes, cycloalkanones on the size of a cycle are analyzed.
Volatile Element Behavior During Melting and Vaporisation on Earth and Protoplanets.
NASA Astrophysics Data System (ADS)
Wood, B. J.; Norris, C. A.
2017-12-01
During accretion the Earth and many of the smaller bodies which were added to it, underwent periods of partial melting, vaporisation and re-condensation. This resulted in patterns of volatile element depletion relative to CI chondrite which are difficult to interpret. The behavior of moderately volatile elements (Pb, Cd, Zn,Cu, In,Tl etc) during these melting, vaporisation and condensation processes is usually approximated by the temperature of condensation from a gas of solar composition. Thus, Tl and In have low condensation temperatures and are regarded as the most volatile of this group. In order to test this volatility approximation we have studied the vaporisation behavior of 13 elements (Ag,Bi,Cd,Cr,Cu,Ga,Ge,In,Pb,Sb,Sn,Tl,Zn) from molten basalt at 1 atm pressure and oxygen fugacities between Ni-NiO and 2 log units below Fe-FeO. The relative volatilities of the elements turn out to be only weakly correlated with condensation temperature, indicating that the latter is a poor proxy for volatility on molten bodies. Cu, Zn and In for example all have similar volatility in the oxygen fugacity range of concern, despite the condensation temperature of Cu (1037K at 10-4bar) being 500K greater than that of In. The oxygen fugacity dependence of volatility indicates that the volatile species are, for all elements more reduced than the melt species. We addressed the differences between condensation temperature and relative volatility in 2 steps. Firstly we used metal-silicate partitioning experiments to estimate the activity coefficients of the trace element oxides in silicate melts. We then used available thermodynamic data to compute the vapor pressures of the stable species of these 13 elements over the silicate melt at oxygen fugacities ranging from Ni-NiO to about 6 log units below Fe-FeO, which approximates the solar gas. Thus we find that presence of Cl and S in the solar gas and the stable Cl and S species of In,Tl Ga Ge Cd and Sn are important contributing factors to volatility in the solar nebula. Our measured volatilities from silicate melt under reducing (S and Cl-absent) conditions are consistent with abundances in the silicate Earth, indicating that these moderately volatile elements were added to Earth in bodies which had undergone episodes of melting and vaporisation.
Theoretical investigation of flash vaporisation in a screw expander
NASA Astrophysics Data System (ADS)
Vasuthevan, Hanushan; Brümmer, Andreas
2017-08-01
In the present study flash vaporisation of liquid injection in a twin screw expander for a Trilateral Flash Cycle (TFC) is examined theoretically. The TFC process comprises a pressure increase in the working fluid, followed by heating the liquid close to boiling point. The hot liquid is injected into the working chamber of a screw expander. During this process the pressure of the liquid drops below the saturation pressure, while the temperature of the liquid remains virtually constant. Hence the liquid is superheated and in a metastable state. The liquid jet seeks to achieve a stable state in thermodynamic equilibrium and is therefore partially vaporised. This effect is referred to as flash vaporisation. Accordingly, a two-phase mixture, consisting of vapour and liquid, exists in the working chamber. Thermodynamic simulations were carried out using water as the working fluid for representative screw expander geometry. The simulations presented are performed from two different aspects during the filling process of a screw expander. The first case is the vaporisation of the injected liquid in a state of thermodynamic equilibrium, whereby the two-phase mixture is treated entirely as a compressible and homogeneous gas. The second case considers flashing efficiency. It describes the quantity of flashed vapour and consists of a liquid and vapour domain. Both models are compared and analysed with respect to the operational behaviour of a screw expander.
Delgado, Alejandra; Posada-Ureta, Oscar; Olivares, Maitane; Vallejo, Asier; Etxebarria, Nestor
2013-12-15
In this study a priority organic pollutants usually found in environmental water samples were considered to accomplish two extraction and analysis approaches. Among those compounds organochlorine compounds, pesticides, phthalates, phenols and residues of pharmaceutical and personal care products were included. The extraction and analysis steps were based on silicone rod extraction (SR) followed by liquid desorption in combination with large volume injection-programmable temperature vaporiser (LVI-PTV) and gas chromatography-mass spectrometry (GC-MS). Variables affecting the analytical response as a function of the programmable temperature vaporiser (PTV) parameters were firstly optimised following an experimental design approach. The SR extraction and desorption conditions were assessed afterwards, including matrix modification, time extraction, and stripping solvent composition. Subsequently, the possibility of performing membrane enclosed sorptive coating extraction (MESCO) as a modified extraction approach was also evaluated. The optimised method showed low method detection limits (3-35 ng L(-1)), acceptable accuracy (78-114%) and precision values (<13%) for most of the studied analytes regardless of the aqueous matrix. Finally, the developed approach was successfully applied to the determination of target analytes in aqueous environmental matrices including estuarine and wastewater samples. © 2013 Elsevier B.V. All rights reserved.
Vaporisation of an ionic liquid near room temperature.
Lovelock, Kevin R J; Deyko, Alexey; Licence, Peter; Jones, Robert G
2010-08-21
The temperature at which the vapour phase of the ionic liquids (ILs) 1-ethyl-3-methylimidazolium bis[(trifluoromethane)sulfonyl]imide, [C(2)C(1)Im][Tf(2)N], and 1-ethyl-3-methylimidazolium ethylsulfate, [C(2)C(1)Im][EtOSO(3)], can be detected was investigated using line-of-sight mass spectrometry (LOSMS). By optimising the detection system used in previous experiments, the lowest temperature for which vapour was detected for [C(2)C(1)Im][Tf(2)N] was approximately 340 K, whereas for [C(2)C(1)Im][EtOSO(3)] it was approximately 390 K. Initial investigations also show that the temperature at which measurements are made affects the enthalpy of vaporisation at 298 K, Delta(vap)H(298). The reasons for these differences in Delta(vap)H(298) with respect to temperature are discussed. The vapour pressure of both ILs is estimated at far lower temperatures than previously achieved and extrapolations to room temperature are given.
Ai, Haiming; Wu, Shuicai; Gao, Hongjian; Zhao, Lei; Yang, Chunlan; Zeng, Yi
2012-01-01
The temperature distribution in the region near a microwave antenna is a critical factor that affects the entire temperature field during microwave ablation of tissue. It is challenging to predict this distribution precisely, because the temperature in the near-antenna region varies greatly. The effects of water vaporisation and subsequent tissue carbonisation in an ex vivo porcine liver were therefore studied experimentally and in simulations. The enthalpy and high-temperature specific absorption rate (SAR) of liver tissues were calculated and incorporated into the simulation process. The accuracy of predictions for near-field temperatures in our simulations has reached the level where the average maximum error is less than 5°C. In addition, a modified thermal model that accounts for water vaporisation and the change in the SAR distribution pattern is proposed and validated with experiment. The results from this study may be useful in the clinical practice of microwave ablation and can be applied to predict the temperature field in surgical planning.
Oberg, T
2007-01-01
The vapour pressure is the most important property of an anthropogenic organic compound in determining its partitioning between the atmosphere and the other environmental media. The enthalpy of vaporisation quantifies the temperature dependence of the vapour pressure and its value around 298 K is needed for environmental modelling. The enthalpy of vaporisation can be determined by different experimental methods, but estimation methods are needed to extend the current database and several approaches are available from the literature. However, these methods have limitations, such as a need for other experimental results as input data, a limited applicability domain, a lack of domain definition, and a lack of predictive validation. Here we have attempted to develop a quantitative structure-property relationship (QSPR) that has general applicability and is thoroughly validated. Enthalpies of vaporisation at 298 K were collected from the literature for 1835 pure compounds. The three-dimensional (3D) structures were optimised and each compound was described by a set of computationally derived descriptors. The compounds were randomly assigned into a calibration set and a prediction set. Partial least squares regression (PLSR) was used to estimate a low-dimensional QSPR model with 12 latent variables. The predictive performance of this model, within the domain of application, was estimated at n=560, q2Ext=0.968 and s=0.028 (log transformed values). The QSPR model was subsequently applied to a database of 100,000+ structures, after a similar 3D optimisation and descriptor generation. Reliable predictions can be reported for compounds within the previously defined applicability domain.
Iron isotope evidence for the origin of the Moon through partial vaporisation
NASA Astrophysics Data System (ADS)
Poitrasson, F.; Halliday, A. N.; Lee, D. C.; Levasseur, S.; Teutsch, N.
2003-04-01
The currently favoured scenario of the origin of the Moon through a Giant Impact, in which a body approaching the size of Mars hit the proto-Earth and yielded ejecta leading to the Moon remains hypothetical. This theory predicts extremely high temperatures, sufficient to induce planetary-scale vaporisation. We have thus measured the Fe isotope composition of the Earth, Moon and meteorites thought to come from Mars and asteroid Vesta to see if this highly energetic process left an imprint. Our analytical method involves Fe purification through anionic exchange chromatography and iron isotope measurement by MC-ICP-MS. Repeat analyses of standards define 57Fe/54Fe reproducibility of 0.09 per mil (2SD). Meteorites from Mars and Vesta, give δ57Fe/54Fe values indistinguishable to the international IRMM-14 Fe isotopic standard. In contrast, ten lunar samples, spanning a large range in composition give a mean 0.2 per mil heavier than IRMM-14. Mantle-derived terrestrial samples yield a mean δ57Fe/54Fe intermediate between the Moon and Mars. Student's t-tests show that the terrestrial mean is significantly different from the averages of Mars, Vesta and the Moon at a confidence level of more than 99%. These new Fe isotope measurements, combined with previous oxygen isotope data rule out alternative theories of the origin of the Moon through co-accretion, capture or fission from the proto-Earth. In contrast, vaporisation of bodies in space can generate kinetic isotope fractionation, leaving residues with a relatively heavier isotope signature. Hence, the Earth, and especially the Moon, can represent such heavy residues having lost part of their light iron through vaporisation. Only the Giant Impact can account for the energy required to partially melt and vaporise major portion of the Earth and the impactor. Rayleigh kinetic isotope calculations suggest that the Moon lost up to 1% of its iron, whereas the Earth lost up to 0.5% during partial vaporisation.
2014-01-01
Background Significant interest has emerged in the therapeutic and interactive effects of different cannabinoids. Cannabidiol (CBD) has been shown to have anxiolytic and antipsychotic effects with high doses administered orally. We report a series of studies conducted to determine the vaporisation efficiency of high doses of CBD, alone and in combination with ∆9-tetrahydrocannabinol (THC), to achieve faster onset effects in experimental and clinical trials and emulate smoked cannabis. Methods Purified THC and CBD (40 mg/ml and 100 mg/ml respectively) were loaded onto a liquid absorbing pad in a Volcano® vaporiser, vaporised and the vapours quantitatively analysed. Preliminary studies determined 200 mg CBD to be the highest dose effectively vaporised at 230°C, yielding an availability of approximately 40% in the vapour phase. Six confirmatory studies examined the quantity of each compound delivered when 200 mg or 4 mg CBD was loaded together with 8 mg of THC. Results THC showed 55% availability when vaporised alone or with low dose CBD, while large variation in the availability of high dose CBD impacted upon the availability of THC when co-administered, with each compound affecting the vaporisation efficiency of the other in a dynamic and dose-dependent manner. We describe optimised protocols that enable delivery of 160 mg CBD through vaporisation. Conclusions While THC administration by vaporisation is increasingly adopted in experimental studies, often with oral predosing with CBD to examine interactive effects, no studies to date have reported the administration of CBD by vaporisation. We report the detailed methodology aimed at optimising the efficiency of delivery of therapeutic doses of CBD, alone and in combination with THC, by vaporisation. These protocols provide a technical advance that may inform methodology for clinical trials in humans, especially for examining interactions between THC and CBD and for therapeutic applications of CBD. Trial registration Current Controlled Trials ISRCTN24109245 PMID:25319497
Solowij, Nadia; Broyd, Samantha J; van Hell, Hendrika H; Hazekamp, Arno
2014-10-16
Significant interest has emerged in the therapeutic and interactive effects of different cannabinoids. Cannabidiol (CBD) has been shown to have anxiolytic and antipsychotic effects with high doses administered orally. We report a series of studies conducted to determine the vaporisation efficiency of high doses of CBD, alone and in combination with ∆9-tetrahydrocannabinol (THC), to achieve faster onset effects in experimental and clinical trials and emulate smoked cannabis. Purified THC and CBD (40 mg/ml and 100 mg/ml respectively) were loaded onto a liquid absorbing pad in a Volcano vaporiser, vaporised and the vapours quantitatively analysed. Preliminary studies determined 200 mg CBD to be the highest dose effectively vaporised at 230 ° C, yielding an availability of approximately 40% in the vapour phase. Six confirmatory studies examined the quantity of each compound delivered when 200 mg or 4 mg CBD was loaded together with 8 mg of THC. THC showed 55% availability when vaporised alone or with low dose CBD, while large variation in the availability of high dose CBD impacted upon the availability of THC when co-administered, with each compound affecting the vaporisation efficiency of the other in a dynamic and dose-dependent manner. We describe optimised protocols that enable delivery of 160 mg CBD through vaporisation. While THC administration by vaporisation is increasingly adopted in experimental studies, often with oral predosing with CBD to examine interactive effects, no studies to date have reported the administration of CBD by vaporisation. We report the detailed methodology aimed at optimising the efficiency of delivery of therapeutic doses of CBD, alone and in combination with THC, by vaporisation. These protocols provide a technical advance that may inform methodology for clinical trials in humans, especially for examining interactions between THC and CBD and for therapeutic applications of CBD. Current Controlled Trials ISRCTN24109245.
Vaporisation of candidate nuclear fuels and targets for transmutation of minor actinides
NASA Astrophysics Data System (ADS)
Gotcu-Freis, P.; Hiernaut, J.-P.; Colle, J.-Y.; Nästrén, C.; Carretero, A. Fernandez; Konings, R. J. M.
2011-04-01
The thermal stability and high temperature behaviour of candidate fuels and targets for transmutation of minor actinides has been investigated. Zirconia-based solid solution, MgO-based CERCER and molybdenum-based CERMET fuels containing Am and/or Pu in various concentrations were heated up to 2700 K in a Knudsen cell coupled with a quadrupole mass spectrometer, to measure their vapour pressure and vapour composition. The results reveal that the vaporisation of the actinides from the samples is not only determined by the thermodynamics of the system but is also related to the dynamic evolution of multi-component mixtures with complex composition or microstructure.
Measuring and predicting Delta(vap)H298 values of ionic liquids.
Deyko, Alexey; Lovelock, Kevin R J; Corfield, Jo-Anne; Taylor, Alasdair W; Gooden, Peter N; Villar-Garcia, Ignacio J; Licence, Peter; Jones, Robert G; Krasovskiy, Vladimir G; Chernikova, Elena A; Kustov, Leonid M
2009-10-14
We report the enthalpies of vaporisation (measured using temperature programmed desorption by mass spectrometry) of twelve ionic liquids (ILs), covering four imidazolium, [C(m)C(n)Im]+, five pyrrolidinium, [C(n)C(m)Pyrr]+, two pyridinium, [C(n)Py]+, and a dication, [C3(C1Im)2]2+ based IL. These cations were paired with a range of anions: [BF4]-, [FeCl4]-, [N(CN)2]-, [PF3(C2F5)3]- ([FAP]-), [(CF3SO2)2N]- ([Tf2N]-) and [SCN]-. Using these results, plus those for a further eight imidazolium based ILs published earlier (which include the anions [CF3SO3]- ([TfO]-), [PF6]- and [EtSO4]-), we show that the enthalpies of vaporisation can be decomposed into three components. The first component is the Coulombic interaction between the ions, DeltaU(Cou,R), which is a function of the IL molar volume, V(m), and a parameter R(r) which quantifies the relative change in anion-cation distance on evaporation from the liquid phase to the ion pair in the gas phase. The second and third components are the van der Waals contributions from the anion, DeltaH(vdw,A), and the cation, DeltaH(vdw,C). We derive a universal value for R(r), and individual values of DeltaH(vdw,A) and DeltaH(vdw,C) for each of the anions and cations considered in this study. Given the molar volume, it is possible to estimate the enthalpies of vaporisation of ILs composed of any combination of the ions considered here; values for fourteen ILs which have not yet been studied experimentally are given.
What are kids vaping? Results from a national survey of US adolescents.
Miech, Richard; Patrick, Megan E; O'Malley, Patrick M; Johnston, Lloyd D
2017-07-01
To examine what substances US youth vape. Data come from Monitoring the Future, an annual, nationally representative survey of USA 12th-grade, 10th-grade and 8th-grade students. Respondents reported what substance they vaped the last time they used a vaporiser such as an e-cigarette. Among students who had ever used a vaporiser, 65-66% last used 'just flavouring' in 12th, in 10th and in 8th grade, more than all other responses combined. In all three grades, the percentage using 'just flavouring' was above 57% for males, females, African-Americans, Hispanics, Whites, and students both with and without a parent with a college degree. Nicotine use came in a distant second, at about 20% in 12th and 10th grade and 13% in 8th grade. Taking into account youth who vaped nicotine at last use increases national estimates of tobacco/nicotine prevalence in the past 30 days by 24-38% above and beyond cigarette smoking, which is substantial but far less than estimates that assume all vaporiser users inhale nicotine. These results challenge the common assumption that all vaporiser users inhale nicotine. They (a) call into question the designation of vaporisers and e-cigarettes as ENDS ('Electronic Nicotine Delivery System'), (b) suggest that the recent rise in adolescent vaporiser use does not necessarily indicate a nicotine epidemic, and (c) indicate that vaporiser users can be candidates for primary prevention programmes. Finally, the results suggest the importance of developing different rationales for the regulation of vaporiser devices as compared to the regulation of substances marketed for vaporiser use. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
McDonald, Emily Anne; Popova, Lucy; Ling, Pamela M
2016-01-01
Objective To explore the intersection of tobacco, legalised marijuana and electronic vaporiser use among young adults in the ‘natural laboratory’ of Colorado, the first state with legalised retail marijuana. Methods We conducted semistructured interviews with 32 young adults (18–26 years old) in Denver, Colorado, in 2015 to understand the beliefs and practices related to the use of tobacco, marijuana and vaporisers. Results We found ambiguity about whether the phrase ‘to smoke’ refers to the use of tobacco or marijuana products. Smoking marijuana blunts (emptied cigarillo or tobacco wrap filled with marijuana) was common, but few interpreted this as tobacco use. Marijuana vaporisers were used to circumvent public consumption laws (eg, while at work or when driving). Young adults considered secondhand tobacco smoke dangerous, but perceived secondhand marijuana smoke as benign. Discussion Using tobacco products as a delivery method for marijuana (eg, blunts) might be increasing and normalising tobacco use among young adults. Surveillance should explicitly ask about use of tobacco products for marijuana. Marijuana vaporisers, often indistinguishable from nicotine vaporisers, may be used to circumvent public consumption laws; communities concerned about use of marijuana in public spaces should include vaporisers (for nicotine or marijuana) in smoke-free regulations. Tobacco, marijuana and electronic vaporisers should be studied together, rather than separately. This approach is essential in informing research and policy as more US states and countries worldwide move to legalise marijuana. PMID:27697954
Knudsen effusion mass spectrometric studies over (USn3+U3Sn7) two-phase region of U-Sn system
NASA Astrophysics Data System (ADS)
Manikandan, P.; Trinadh, V. V.; Bera, Suranjan; Narasimhan, T. S. Lakshmi; Ananthasivan, K.; Joseph, M.; Mudali, U. Kamachi
2017-08-01
Vaporisation studies over (USn3+U3Sn7) ;two-phase; field have been carried out by employing Knudsen effusion mass spectrometry (KEMS) in the temperature range of 1050-1226 K. Sn(g) was the species observed in the mass spectrum of the equilibrium vapour phase over the samples (71.5 at% Sn and 73.0 at% Sn). The partial pressure of Sn(g) was measured as a function of temperature over (USn3+U3Sn7) ;two-phase; field and the p-T relation was derived as log (pSn/Pa) = ((-14580 ± 91)/(T/K)) + (8.82 ± 0.08) (1050-1226 K). The vaporisation reaction 3USn3(s) = U3Sn7(s) + 2Sn(g) was evaluated by second law method. The Gibbs energy of formation of USn3(s) was derived as ΔfGm°(U Sn3 , s , T) (±1.8) = -173.4 + 0.055 T (K) (kJ mol-1) (1050-1226 K). The mass spectrometric studies on this system have been carried out for the first time.
NASA Astrophysics Data System (ADS)
Lin, Shengtao; Zhang, Ge; Jamburidze, Akaki; Chee, Melisse; Hau Leow, Chee; Garbin, Valeria; Tang, Meng-Xing
2018-03-01
Phase-change ultrasound contrast agent (PCCA), or nanodroplet, shows promise as an alternative to the conventional microbubble agent over a wide range of diagnostic applications. Meanwhile, high-frame-rate (HFR) ultrasound imaging with microbubbles enables unprecedented temporal resolution compared to traditional contrast-enhanced ultrasound imaging. The combination of HFR ultrasound imaging and PCCAs can offer the opportunity to observe and better understand PCCA behaviour after vaporisation captures the fast phenomenon at a high temporal resolution. In this study, we utilised HFR ultrasound at frame rates in the kilohertz range (5-20 kHz) to image native and size-selected PCCA populations immediately after vaporisation in vitro within clinical acoustic parameters. The size-selected PCCAs through filtration are shown to preserve a sub-micron-sized (mean diameter < 200 nm) population without micron-sized outliers (>1 µm) that originate from native PCCA emulsion. The results demonstrate imaging signals with different amplitudes and temporal features compared to that of microbubbles. Compared with the microbubbles, both the B-mode and pulse-inversion (PI) signals from the vaporised PCCA populations were reduced significantly in the first tens of milliseconds, while only the B-mode signals from the PCCAs were recovered during the next 400 ms, suggesting significant changes to the size distribution of the PCCAs after vaporisation. It is also shown that such recovery in signal over time is not evident when using size-selective PCCAs. Furthermore, it was found that signals from the vaporised PCCA populations are affected by the amplitude and frame rate of the HFR ultrasound imaging. Using high-speed optical camera observation (30 kHz), we observed a change in particle size in the vaporised PCCA populations exposed to the HFR ultrasound imaging pulses. These findings can further the understanding of PCCA behaviour under HFR ultrasound imaging.
1977-01-01
circumstances for determining the onset with light scattering is that in which the laser is so powerful and/or the detector so sensitive that the...sec Boltzmann’s constant 1.38 x 10~16 ergs/mole, wave number length of detector window latent heat of vaporisation mass flow rate of steam In...constant, distance from light scattering volume to detector S supersaturation ratio, p /p t time T local temperature of vapor T temperature in
Drug Vaping: From the Dangers of Misuse to New Therapeutic Devices.
Varlet, V
2016-12-16
Users of e-cigarettes are unwitting volunteers participating in a worldwide epidemiological study. Because of the obvious benefits of e-cigarettes compared with traditional cigarette smoking, these electronic devices have been introduced all around the world to support tobacco smoking cessation. Same potential harm reduction could be considered by cannabis vaping for marijuana smokers. However, the toxicities of liquids and aerosols remain under investigation because although the use of e-cigarettes is likely to be less harmful than traditional cigarette smoking, trace levels of contaminants have been identified. Simultaneously, other electronic devices, such as e-vaporisers, e-hookahs or e-pipes, have been developed and commercialised. Consequently, misuse of electronic devices has increased, and experimentation has been documented on Internet web fora. Although legal and illegal drugs are currently consumed with these e-devices, no scientific papers are available to support the observations reported by numerous media and web fora. Moreover, building on illegal drug vaping and vaporisation with e-devices (vaping misuse), legal drug vaping (an alternative use of vaping) could present therapeutic benefits, as occurs with medical cannabis vaporisation with table vaporisers. This review seeks to synthesise the problems of e-cigarette and liquid refill toxicity in order to introduce the dangers of illegal and legal drugs consumed using vaping and vaporisation for recreational purposes, and finally, to present the potential therapeutic benefits of vaping as a new administration route for legal drugs.
Selective intracellular vaporisation of antibody-conjugated phase-change nano-droplets in vitro
NASA Astrophysics Data System (ADS)
Ishijima, A.; Minamihata, K.; Yamaguchi, S.; Yamahira, S.; Ichikawa, R.; Kobayashi, E.; Iijima, M.; Shibasaki, Y.; Azuma, T.; Nagamune, T.; Sakuma, I.
2017-03-01
While chemotherapy is a major mode of cancer therapeutics, its efficacy is limited by systemic toxicities and drug resistance. Recent advances in nanomedicine provide the opportunity to reduce systemic toxicities. However, drug resistance remains a major challenge in cancer treatment research. Here we developed a nanomedicine composed of a phase-change nano-droplet (PCND) and an anti-cancer antibody (9E5), proposing the concept of ultrasound cancer therapy with intracellular vaporisation. PCND is a liquid perfluorocarbon nanoparticle with a liquid-gas phase that is transformable upon exposure to ultrasound. 9E5 is a monoclonal antibody targeting epiregulin (EREG). We found that 9E5-conjugated PCNDs are selectively internalised into targeted cancer cells and kill the cells dynamically by ultrasound-induced intracellular vaporisation. In vitro experiments show that 9E5-conjugated PCND targets 97.8% of high-EREG-expressing cancer cells and kills 57% of those targeted upon exposure to ultrasound. Furthermore, direct observation of the intracellular vaporisation process revealed the significant morphological alterations of cells and the release of intracellular contents.
Drug Vaping: From the Dangers of Misuse to New Therapeutic Devices
Varlet, V.
2016-01-01
Users of e-cigarettes are unwitting volunteers participating in a worldwide epidemiological study. Because of the obvious benefits of e-cigarettes compared with traditional cigarette smoking, these electronic devices have been introduced all around the world to support tobacco smoking cessation. Same potential harm reduction could be considered by cannabis vaping for marijuana smokers. However, the toxicities of liquids and aerosols remain under investigation because although the use of e-cigarettes is likely to be less harmful than traditional cigarette smoking, trace levels of contaminants have been identified. Simultaneously, other electronic devices, such as e-vaporisers, e-hookahs or e-pipes, have been developed and commercialised. Consequently, misuse of electronic devices has increased, and experimentation has been documented on Internet web fora. Although legal and illegal drugs are currently consumed with these e-devices, no scientific papers are available to support the observations reported by numerous media and web fora. Moreover, building on illegal drug vaping and vaporisation with e-devices (vaping misuse), legal drug vaping (an alternative use of vaping) could present therapeutic benefits, as occurs with medical cannabis vaporisation with table vaporisers. This review seeks to synthesise the problems of e-cigarette and liquid refill toxicity in order to introduce the dangers of illegal and legal drugs consumed using vaping and vaporisation for recreational purposes, and finally, to present the potential therapeutic benefits of vaping as a new administration route for legal drugs. PMID:29051432
Rodríguez, Pablo Fernández; Marchante-Gayón, Juan Manuel; Sanz-Medel, Alfredo
2006-01-15
Ultrasonic slurry sampling electrothermal vaporisation inductively coupled plasma mass spectrometry (USS-ETV-ICP-MS) was applied to the elemental analysis of silicate based minerals, such as talc or quartz, without any pre-treatment except the grinding of the sample. The electrothermal vaporisation device consists of a tungsten coil connected to a home-made power supply. The voltage program, carrier gas flow rate and sonication time were optimised in order to obtain the best sensitivity for elements determined. The relationship between the amount of sample in the slurry and the signal intensity was also evaluated. Unfortunately, in all cases, quantification had to be carried out by the standard additions method owing to the strong matrix interferences. The global precision of the proposed method was always better than 12%. The limits of detection, calculated as three times the standard deviation of the blank value divided by the slope of the calibration curve, were between 0.5 ng/g for As and 3.5 ng/g for Ba. The method was validated by comparing the concentrations found for Cu, Mn, Cr, V, Li, Pb, Sn, Mg, U, Ba, Sr, Zn, Sb, Rb and Ce using the proposed methodology with those obtained by conventional nebulisation ICP-MS after acid digestion of the samples in a microwave oven. The concentration range in the solid samples was between 0.2 microg/g for Cr and 60 microg/g for Ba. All results were statistically in agreement with those found by conventional nebulisation.
NASA Astrophysics Data System (ADS)
Suriani, A. B.; Dalila, A. R.; Mohamed, A.; Rosmi, M. S.; Mamat, M. H.; Malek, M. F.; Ahmad, M. K.; Hashim, N.; Isa, I. M.; Soga, T.; Tanemura, M.
2016-12-01
High-quality vertically aligned carbon nanotubes (VACNTs) were synthesised using ferrocene-chicken oil mixture utilising a thermal chemical vapour deposition (TCVD) method. Reaction parameters including vaporisation temperature, catalyst concentration and synthesis time were examined for the first time to investigate their influence on the growth of VACNTs. Analysis via field emission scanning electron microscopy and micro-Raman spectroscopy revealed that the growth rate, diameter and crystallinity of VACNTs depend on the varied synthesis parameters. Vaporisation temperature of 570°C, catalyst concentration of 5.33 wt% and synthesis time of 60 min were considered as optimum parameters for the production of VACNTs from waste chicken fat. These parameters are able to produce VACNTs with small diameters in the range of 15-30 nm and good quality (ID/IG 0.39 and purity 76%) which were comparable to those synthesised using conventional carbon precursor. The low turn on and threshold fields of VACNTs synthesised using optimum parameters indicated that the VACNTs synthesised using waste chicken fat are good candidate for field electron emitter. The result of this study therefore can be used to optimise the growth and production of VACNTs from waste chicken fat in a large scale for field emission application.
Vitorino, Joana; Bernardes, Carlos E S; Minas da Piedade, Manuel E
2012-04-07
A general strategy to determine enthalpies of formation of protic ionic liquids, based solely on enthalpy of solution measurements, was conceived and tested for 1-methylimidazolium ethanoate, leading to Δ(f)H°(m){[Hmim][O(2)CCH(3)], 1} = -(425.7 ± 1.2) kJ mol(-1). This result in conjunction with the enthalpy of formation of gaseous 1-methylimidazole (mim) proposed in this work, Δ(f)H°(m)(mim, g) = 126.5 ± 1.1 kJ mol(-1), and Δ(f)H°(m)(CH(3)COOH, g) taken from the literature, allowed the calculation of the enthalpy of the vaporisation process [Hmim][O(2)CCH(3)](l) → mim(g) + CH(3)COOH(g) as Δ(vap)H°(m){[Hmim][O(2)CCH(3)]} = 119.4 ± 3.0 kJ mol(-1). The agreement between this value and Δ(vap)H°(m){[Hmim][O(2)CCH(3)]} = 117.3 ± 0.5 kJ mol(-1), obtained for the direct vaporisation of [Hmim][O(2)CCH(3)], by Calvet-drop microcalorimetry, gives a good indication that, as previously suggested by Fourier transform ion cyclotron resonance mass spectrometry, Raman spectroscopy, and GC-MS experiments, the vaporisation of [Hmim][O(2)CCH(3)] essentially involves a proton transfer mechanism with formation of the two volatile neutral precursor molecules (mim and CH(3)COOH). Although being a low ionicity protic ionic liquid, [Hmim][O(2)CCH(3)] was chosen to validate the methodology proposed here, since its vaporisation mechanism has been unequivocally demonstrated by different methods and for different pressure ranges.
NASA Astrophysics Data System (ADS)
Lin, Shengtao; Zhang, Ge; Hau Leow, Chee; Tang, Meng-Xing
2017-09-01
The sub-micron phase change contrast agent (PCCA) composed of a perfluorocarbon liquid core can be activated into gaseous state and form stable echogenic microbubbles for contrast-enhanced ultrasound imaging. It has shown great promise in imaging microvasculature, tumour microenvironment, and cancer cells. Although PCCAs have been extensively studied for different diagnostic and therapeutic applications, the effect of biologically geometrical confinement on the acoustic vaporisation of PCCAs is still not clear. We have investigated the difference in PCCA-produced ultrasound contrast enhancement after acoustic activation with and without a microvessel confinement on a microchannel phantom. The experimental results indicated more than one-order of magnitude less acoustic vaporisation in a microchannel than that in a free environment taking into account the attenuation effect of the vessel on the microbubble scattering. This may provide an improved understanding in the applications of PCCAs in vivo.
NASA Astrophysics Data System (ADS)
Hu, Yong; Olguin, Hernan; Gutheil, Eva
2017-05-01
A spray flamelet/progress variable approach is developed for use in spray combustion with partly pre-vaporised liquid fuel, where a laminar spray flamelet library accounts for evaporation within the laminar flame structures. For this purpose, the standard spray flamelet formulation for pure evaporating liquid fuel and oxidiser is extended by a chemical reaction progress variable in both the turbulent spray flame model and the laminar spray flame structures, in order to account for the effect of pre-vaporised liquid fuel for instance through use of a pilot flame. This new approach is combined with a transported joint probability density function (PDF) method for the simulation of a turbulent piloted ethanol/air spray flame, and the extension requires the formulation of a joint three-variate PDF depending on the gas phase mixture fraction, the chemical reaction progress variable, and gas enthalpy. The molecular mixing is modelled with the extended interaction-by-exchange-with-the-mean (IEM) model, where source terms account for spray evaporation and heat exchange due to evaporation as well as the chemical reaction rate for the chemical reaction progress variable. This is the first formulation using a spray flamelet model considering both evaporation and partly pre-vaporised liquid fuel within the laminar spray flamelets. Results with this new formulation show good agreement with the experimental data provided by A.R. Masri, Sydney, Australia. The analysis of the Lagrangian statistics of the gas temperature and the OH mass fraction indicates that partially premixed combustion prevails near the nozzle exit of the spray, whereas further downstream, the non-premixed flame is promoted towards the inner rich-side of the spray jet since the pilot flame heats up the premixed inner spray zone. In summary, the simulation with the new formulation considering the reaction progress variable shows good performance, greatly improving the standard formulation, and it provides new insight into the local structure of this complex spray flame.
Mathematical Simulation of Drying Process of Fibrous Material
NASA Astrophysics Data System (ADS)
Blejchař, Tomáš; Raška, Jiří; Jablonská, Jana
2018-06-01
The article describes mathematical simulation of flowing air through porous zone and water vaporisation from mentioned porous area which actually represents dried fibrous material - cotton towel. Simulation is based on finite volume method. Wet towel is placed in pipe and hot air flow through the towel. Water from towel is evaporated. Simulation of airflow through porous element is described first. Eulerian multiphase model is then used for simulation of water vaporisation from porous medium. Results of simulation are compared with experiment. Ansys Fluent 13.0 was used for calculation.
NASA Astrophysics Data System (ADS)
Teulet, Philippe; Billoux, Tommy; Cressault, Yann; Masquère, Mathieu; Gleizes, Alain; Revel, Ivan; Lepetit, Bruno; Peres, Gilles
2017-03-01
This work is devoted to the calculation of the energy balance associated with the formation of an electric arc between the bolt shank and an inner structural part of the fuselage during a lightning strike. Assessment of the pressure build-up in the confined volume around the bolt fastener has also been performed. This pressure rise comes from the temperature increase and from the mass density increase (melting and vaporisation of materials). Previous electrical measurements performed by Airbus Group during a lightning test campaign have been used to calculate the total available electrical energy. The energies necessary for melting and vaporisation of bolt and rib are derived from thermodynamic properties of aluminium and titanium. A numerical code has been developed to determine the chemical composition (under the local thermodynamic equilibrium [LTE] assumption) and the internal energy of the plasma for air-Al/Ti mixtures. Plasma and material radiation losses and heat conduction losses have also been evaluated. Finally, an analytical model has been implemented to determine the overpressure as a function of the deposited electrical energy, the energy involved in the arc formation, the energy necessary for melting and the plasma composition and mass density. With this approach, maximum pressure values are in the range 200-330 bars.
Bulk properties and near-critical behaviour of SiO2 fluid
NASA Astrophysics Data System (ADS)
Green, Eleanor C. R.; Artacho, Emilio; Connolly, James A. D.
2018-06-01
Rocky planets and satellites form through impact and accretion processes that often involve silicate fluids at extreme temperatures. First-principles molecular dynamics (FPMD) simulations have been used to investigate the bulk thermodynamic properties of SiO2 fluid at high temperatures (4000-6000 K) and low densities (500-2240 kg m-3), conditions which are relevant to protoplanetary disc condensation. Liquid SiO2 is highly networked at the upper end of this density range, but depolymerises with increasing temperature and volume, in a process characterised by the formation of oxygen-oxygen (Odbnd O) pairs. The onset of vaporisation is closely associated with the depolymerisation process, and is likely to be non-stoichiometric at high temperature, initiated via the exsolution of O2 molecules to leave a Si-enriched fluid. By 6000 K the simulated fluid is supercritical. A large anomaly in the constant-volume heat capacity occurs near the critical temperature. We present tabulated thermodynamic properties for silica fluid that reconcile observations from FPMD simulations with current knowledge of the SiO2 melting curve and experimental Hugoniot curves.
Study of a two-bed silica gel-water adsorption chiller: performance analysis
NASA Astrophysics Data System (ADS)
Sah, Ramesh P.; Choudhury, Biplab; Das, Ranadip K.
2018-01-01
In this study, a lumped parameter simulation model has been developed for analysis of the thermal performance of a single-stage two-bed adsorption chiller. Since silica gel has low regeneration temperature and water has high latent heat of vaporisation, silica gel-water pair has been chosen as the working pair of the adsorption chiller. Low-grade waste heat or solar heat at around 70-80°C can be used to run this adsorption chiller. In this model, the effects of operating parameters on the performance of the chiller have been studied. The simulated results show that the cooling capacity of the chiller has an optimum value of 5.95 kW for a cycle time of 1600 s with the hot, cooling, and chilled water inlet temperatures at 85°C, 25°C, and 14°C, respectively. The present model can be utilised to investigate and optimise adsorption chillers.
NASA Astrophysics Data System (ADS)
Koch, Holger; Kägeler, Christian; Otto, Andreas; Schmidt, Michael
Welding of zinc coated sheets in zero gap configuration is of eminent interest for the automotive industry. This Laser welding process would enable the automotive industry to build auto bodies with a high durability in a plain manufacturing process. Today good welding results can only be achieved by expensive constructive procedures such as clamping devices to ensure a defined gad. The welding in zero gap configuration is a big challenge because of the vaporised zinc expelled from the interface between the two sheets. To find appropriate welding parameters for influencing the keyhole and melt pool dynamics, a three dimensional simulation and a high speed imaging system for laser keyhole welding have been developed. The obtained results help to understand the process of the melt pool perturbation caused by vaporised zinc.
Indirect contact freeze water desalination for an ice maker machine - CFD simulation
NASA Astrophysics Data System (ADS)
Jayakody, Harith; Al-Dadah, Raya; Mahmoud, Saad
2017-11-01
To offer for potable water shortages, sea water desalination is a potential solution for the global rising demand for fresh water. The latent heat of fusion is about one-seventh the latent heat of vaporisation, thus indicating the benefit of lower energy consumption for the freeze desalination process. Limited literature is reported on computational fluid dynamics (CFD) on freeze desalination. Therefore, analysing and investigating thermodynamic processes are easily conducted by the powerful tool of CFD. A single unit of ice formation in an ice maker machine was modelled using ANSYS Fluent software three-dimensionally. Energy, species transport and solidification/melting modules were used in building the CFD model. Parametric analysis was conducted using the established CFD model to predict the effects of freezing temperature and the geometry of the ice maker machine; on ice production and the freezing time. Lower freezing temperatures allowed more ice production and faster freezing. Increasing the diameter and the length of the freezing tube enabled more ice to be produced.
Pillai, Ravisankar G; Al Naieb, Ziad; Angamuthu, Stephen; Mundackal, Tintu
2014-12-01
To compare the perioperative morbidity and early follow-up after diode laser vaporisation of the prostate (LVP) and its modification, diode laser under cold irrigation (LUCI) in patients with symptomatic benign prostatic hyperplasia, as the main disadvantages of LVP are the postoperative pain, dysuria and storage urinary symptoms. This was a single-centre prospective randomised control trial in which 100 patients were randomised to receive LVP (50) or LUCI (50) from June 2011 until July 2012. LUCI is similar to LVP except that it is done under normal irrigation with saline at 4 °C instead of saline at room temperature. The primary outcome measures were the International Prostate Symptom Score (IPSS), IPSS-Dysuria, a pain scale (PS), maximum flow rate (Q max), a quality-of-life (QoL) score and the postvoid residual urine volume (PVR) after 1 month, then the IPSS, Q max, QoL, and PVR at 3 and 12 months. Secondary outcomes included intraoperative surgical variables, e.g., the decline in core temperature, bleeding, peri- and postoperative morbidity. The baseline characteristics of both groups were similar. For the primary outcome measures, there was a statistically significant difference between the groups in all variables except Q max after 1 month, in favour of LUCI. The mean (SD) IPSS at 1 month in the LVP group was 8.97 (1.68), statistically significantly different from that after LUCI, of 6.89 (1.5) (P < 0.05). The mean IPSS-Dysuria at 1 month was also significantly, at -2.32 (0.91) for LVP and 3.54 (1.07) for LUCI (P < 0.05). The respective mean PS at 1 month was 7.84 (2.92) and 5.7 (2.1) (P < 0.05). The QoL and PVR at 1 month were also significantly different. Within the first month 17% of patients in the LVP group and 4% in the LUCI group complained of transient urgency or stress incontinence, and this difference was statistically significant (P < 0.05). There was no significant bleeding in either group. The mean operative time or applied energy of LVP was not statistically significant from that of LUCI, and there was no significant difference in the decline in core temperature between the groups (P > 0.05). LUCI is a good modification for reducing the pain, dysuria and storage symptoms associated with LVP. The procedure appears to be safe, with no significant decrease in core temperature in either group.
Aydin, Abdullatif; Muir, Gordon H; Graziano, Manuela E; Khan, Muhammad Shamim; Dasgupta, Prokar; Ahmed, Kamran
2015-06-01
To assess face, content and construct validity, and feasibility and acceptability of the GreenLight™ Simulator as a training tool for photoselective vaporisation of the prostate (PVP), and to establish learning curves and develop an evidence-based training curriculum. This prospective, observational and comparative study, recruited novice (25 participants), intermediate (14) and expert-level urologists (seven) from the UK and Europe at the 28th European Association of Urological Surgeons Annual Meeting 2013. A group of novices (12 participants) performed 10 sessions of subtask training modules followed by a long operative case, whereas a second group (13) performed five sessions of a given case module. Intermediate and expert groups performed all training modules once, followed by one operative case. The outcome measures for learning curves and construct validity were time to task, coagulation time, vaporisation time, average sweep speed, average laser distance, blood loss, operative errors, and instrument cost. Face and content validity, feasibility and acceptability were addressed through a quantitative survey. Construct validity was demonstrated in two of five training modules (P = 0.038; P = 0.018) and in a considerable number of case metrics (P = 0.034). Learning curves were seen in all five training modules (P < 0.001) and significant reduction in case operative time (P < 0.001) and error (P = 0.017) were seen. An evidence-based training curriculum, to help trainees acquire transferable skills, was produced using the results. This study has shown the GreenLight Simulator to be a valid and useful training tool for PVP. It is hoped that by using the training curriculum for the GreenLight Simulator, novice trainees can acquire skills and knowledge to a predetermined level of proficiency. © 2014 The Authors. BJU International © 2014 BJU International.
Modelling of catastrophic flashing releases.
Deaves, D M; Gilham, S; Mitchell, B H; Woodburn, P; Shepherd, A M
2001-11-16
Several low boiling point materials are stored in closed vessels at ambient temperature, using their own vapour pressure to maintain a liquid state. These materials are often toxic, flammable, or both, and thus any uncontrolled release can have potentially disastrous consequences. There are many ways in which an accidental release can occur, the most severe being due to catastrophic vessel failure. Although not the most common, this mode of failure has the potential to result in an instantaneous loss of the entire vessel inventory in the form of a rapidly expanding, two-phase, vaporising cloud. This paper provides a comprehensive review of the physical processes of existing models and of available experimental and incident data to model such scenarios. Subsequently, this has enabled the development of an improved methodology for the characterisation of the source conditions following catastrophic vessel failures.
NASA Technical Reports Server (NTRS)
Yule, A. J.; Seng, C. A.; Boulderstone, R.; Ungut, A.; Felton, P. G.; Chigier, N. A.
1980-01-01
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.
Sauzier, Georgina; Bors, Dana; Ash, Jordan; Goodpaster, John V; Lewis, Simon W
2016-09-01
The investigation of explosive events requires appropriate evidential protocols to recover and preserve residues from the scene. In this study, a central composite design was used to determine statistically validated optimum recovery parameters for double-base smokeless powder residues on steel, analysed using total vaporisation (TV) SPME/GC-MS. It was found that maximum recovery was obtained using isopropanol-wetted swabs stored under refrigerated conditions, then extracted for 15min into acetone on the same day as sample collection. These parameters were applied to the recovery of post-blast residues deposited on steel witness surfaces following a PVC pipe bomb detonation, resulting in detection of all target components across the majority of samples. Higher overall recoveries were obtained from plates facing the sides of the device, consistent with the point of first failure occurring in the pipe body as observed in previous studies. The methodology employed here may be readily applied to a variety of other explosive compounds, and thus assist in establishing 'best practice' procedures for explosive investigations. Copyright © 2016 Elsevier B.V. All rights reserved.
Ganesh, D; Nagarajan, G; Ganesan, S
2014-01-01
In parallel to the interest in renewable fuels, there has also been increased interest in homogeneous charge compression ignition (HCCI) combustion. HCCI engines are being actively developed because they have the potential to be highly efficient and to produce low emissions. Even though HCCI has been researched extensively, few challenges still exist. These include controlling the combustion at higher loads and the formation of a homogeneous mixture. To obtain better homogeneity, in the present investigation external mixture formation method was adopted, in which the fuel vaporiser was used to achieve excellent HCCI combustion in a single cylinder air-cooled direct injection diesel engine. In continuation of our previous works, in the current study a vaporised jatropha methyl ester (JME) was mixed with air to form a homogeneous mixture and inducted into the cylinder during the intake stroke to analyze the combustion, emission and performance characteristics. To control the early ignition of JME vapor-air mixture, cooled (30 °C) Exhaust gas recirculation (EGR) technique was adopted. The experimental result shows 81% reduction in NOx and 72% reduction in smoke emission.
Ma, Bernice Hua; Yong, Hua‐Hie; McNeill, Ann; Hitchman, Sara C.
2017-01-01
Abstract Introduction and Aims. Personal vaporisers (PV), including e‐cigarettes, may be a harm reduction strategy for tobacco control. This study aims to identify factors associated with future intentions to vape among smokers and ex‐smokers in Australia and the UK. Design and Methods. Cross‐sectional data of smokers and ex‐smokers (n = 1199, mean age = 45.3 years, 44.8% male), collected in 2014/2015 and divided into four subgroups: smoking past vapers (SPV), smoking vapers (SV), ex‐smoking past vapers (ESPV) and ex‐smoking vapers (ESV), from the International Tobacco Control Australia and UK surveys were analysed by using regression models. Results. Higher vaping satisfaction increased vaping intentions for all groups except ESPV. Perceiving PVs as less harmful predicted intentions to vape for all groups except ESV. The importance of PVs for stopping smoking predicted lower intentions to continue vaping for SV, but higher intentions to initiate vaping for SPV. The importance of PVs for cutting down smoking was a positive predictor only for SPV. Among ex‐smokers, importance for maintaining not smoking was a positive predictor for ESPV, but not for ESV. The importance of perceiving vapour being less harmful also depended on vaping status for ex‐smokers. The only country interaction was that only in the UK was perceiving PVs as less harmful associated with intention among SPV. Discussion and Conclusion. Factors influencing intentions vary by smoking and/or vaping status, with greater differences between the ex‐smoker subgroups. This is consistent with PVs being seen as a way of managing smoking, rather than something that has intrinsic value, for all except the ex‐smoking vapers. [Ma BH, Yong H‐H, Borland R, McNeill A, Hitchman SC. Factors associated with future intentions to use personal vaporisers among those with some experience of vaping. Drug Alcohol Rev 2017;00:000–000] PMID:28560806
Ethanol turbulent spray flame response to gas velocity modulation
NASA Astrophysics Data System (ADS)
Fratalocchi, Virginia; Kok, Jim B. W.
2018-01-01
A numerical investigation of the interaction between a spray flame and an acoustic forcing of the velocity field is presented in this paper. In combustion systems, a thermoacoustic instability is the result of a process of coupling between oscillations in heat released and acoustic waves. When liquid fuels are used, the atomisation and the evaporation process also undergo the effects of such instabilities, and the computational fluid dynamics of these complex phenomena becomes a challenging task. In this paper, an acoustic perturbation is applied to the mass flow of the gas phase at the inlet and its effect on the evaporating fuel spray and on the flame front is investigated with unsteady Reynolds averaged Navier-Stokes numerical simulations. Two flames are simulated: a partially premixed ethanol/air spray flame and a premixed pre-vaporised ethanol/air flame, with and without acoustic forcing. The frequencies used to perturb the flames are 200 and 2500 Hz, which are representative for two different regimes. Those regimes are classified based on the Strouhal number St = (D/U)ff: at 200 Hz, St = 0.07, and at 2500 Hz, St = 0.8. The exposure of the flame to a 200 Hz signal results in a stretching of the flame which causes gas field fluctuations, a delay of the evaporation and an increase of the reaction rate. The coupling between the flame and the flow excitation is such that the flame breaks up periodically. At 2500 Hz, the evaporation rate increases but the response of the gas field is weak and the flame is more stable. The presence of droplets does not play a crucial role at 2500 Hz, as shown by a comparison of the discrete flame function in the case of spray and pre-vaporised flame. At low Strouhal number, the forced response of the pre-vaporised flame is much higher compared to that of the spray flame.
Ma, Bernice Hua; Yong, Hua-Hie; Borland, Ron; McNeill, Ann; Hitchman, Sara C
2018-02-01
Personal vaporisers (PV), including e-cigarettes, may be a harm reduction strategy for tobacco control. This study aims to identify factors associated with future intentions to vape among smokers and ex-smokers in Australia and the UK. Cross-sectional data of smokers and ex-smokers (n = 1199, mean age = 45.3 years, 44.8% male), collected in 2014/2015 and divided into four subgroups: smoking past vapers (SPV), smoking vapers (SV), ex-smoking past vapers (ESPV) and ex-smoking vapers (ESV), from the International Tobacco Control Australia and UK surveys were analysed by using regression models. Higher vaping satisfaction increased vaping intentions for all groups except ESPV. Perceiving PVs as less harmful predicted intentions to vape for all groups except ESV. The importance of PVs for stopping smoking predicted lower intentions to continue vaping for SV, but higher intentions to initiate vaping for SPV. The importance of PVs for cutting down smoking was a positive predictor only for SPV. Among ex-smokers, importance for maintaining not smoking was a positive predictor for ESPV, but not for ESV. The importance of perceiving vapour being less harmful also depended on vaping status for ex-smokers. The only country interaction was that only in the UK was perceiving PVs as less harmful associated with intention among SPV. Factors influencing intentions vary by smoking and/or vaping status, with greater differences between the ex-smoker subgroups. This is consistent with PVs being seen as a way of managing smoking, rather than something that has intrinsic value, for all except the ex-smoking vapers. [Ma BH, Yong H-H, Borland R, McNeill A, Hitchman SC. Factors associated with future intentions to use personal vaporisers among those with some experience of vaping. Drug Alcohol Rev 2017;00:000-000]. © 2017 The Authors Drug and Alcohol Review published by John Wiley & Sons Australia, Ltd on behalf of Australasian Professional Society on Alcohol and other Drugs.
Vaporisation of a dicationic ionic liquid.
Lovelock, Kevin R J; Deyko, Alexey; Corfield, Jo-Anne; Gooden, Peter N; Licence, Peter; Jones, Robert G
2009-02-02
Highest heat of vaporization yet: The dicationic ionic liquid [C(3)(C(1)Im)(2)][Tf(2)N](2) evaporates as a neutral ion triplet. These neutral ion triplets can then be ionised to form singly and doubly charged ions. The mass spectrum exhibits the dication attached to one remaining anion, and the naked dication itself (see picture).
NASA Astrophysics Data System (ADS)
Zampolli, M.; Sternberg, R.; Szopa, C.; Pietrogrande, M. C.; Buch, A.; Dondi, F.; Raulin, F.
The search for optical activity in extraterrestrial sample is an important key for the study of the origin of life With this aim detection of chemical biomarkers i e of organic molecules which play an important role in biochemistry will be one of the main goals of future space missions To reach this goal an investigation of a GC-MS method based on the derivatization of amino acids by using a mixture of perfluorinated alcohols and perfluorinated anhydrides has been performed Amino acids are converted in their N O S -perfluoroacyl perfluoroalkyl esters in a single step procedure using different combinations of the derivatization reagents trifluoroacetic anhydride TFAA - 2 2 2-trifluoro-1-ethanol TFE TFAA-2 2 3 3 4 4 4-heptafluoro-1-butanol HFB heptafluorobutyric anhydride HFBA -HFB The obtained derivatives are analyzed using two different chiral columns a Chirasil-L-Val and a gammat cyclodextrin Rt- gamma -DEXsa stationary phases which show different and complementary enantiomeric selectivity The mass spectra of the derivatized compounds are studied and mass fragmentation patterns are proposed significant fragment ions can be identified to detect amino acid derivatives The obtained results are compared in terms of the enantiomeric separation achieved and mass spectrometric response Linearity studies and the measurement of the limit of detection LOD prove that the proposed method is suitable for a quantitative determination of several amino acids enantiomers 1 The use of a PTV Programmed Temperature Vaporiser
Lin, Mei-Ling; Jiang, Shiuh-Jen
2013-12-01
Inductively coupled plasma mass spectrometry coupled with ultrasonic slurry sampling electrothermal vaporisation (USS-ETV-ICP-MS) has been applied to determine As, Cd, Hg and Pb in 0.5% m/v slurries of several herb samples. 1% m/v 8-Hydroxyquinoline was used as the modifier to enhance the ion signals. The influences of instrument operating conditions, slurry preparation and interferences on the ion signals were reported. This method has been applied to the determination of As, Cd, Hg and Pb in NIST SRM 1547 peach leaves and SRM 1573a tomato leaves reference materials and three herb samples purchased from the local market and ground to 150 μm. The analysis results of the standard reference materials agreed with the certified values which are at sub μg g(-1) levels. Precision between sample replicates was better than 4% for all the determinations. The method detection limits estimated from standard addition curves were about 0.3, 0.1, 0.1 and 0.2 ng g(-1) for As, Cd, Hg and Pb, respectively, in original herb samples. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Manikandan, P.; Trinadh, V. V.; Bera, Suranjan; Narasimhan, T. S. Lakshmi; Joseph, M.
2016-07-01
Vaporisation studies over gallium rich biphasic regions (U3Ga5 + UGa2) and (UGa2 + UGa3) in the Usbnd Ga system were carried out by Knusen effusion mass spectrometry in the temperature ranges of 1208-1366 K and 1133-1338 K, respectively. Ga(g) was the species observed in the mass spectra of the equilibrium vapour over both phase regions. From temperature dependence measurements, pressure-temperature relations were deduced as: log (pGa/Pa) = (-18216 ± 239)/(T/K) + (12.88 ± 0.18) over (U3Ga5 + UGa2) and log (pGa/Pa) = (-16225 ± 124)/(T/K) + (11.78 ± 0.10) over (UGa2 + UGa3). From these data, Gibbs free energy changes for the reactions 3UGa2(s) = U3Ga5(s) + Ga(g) and UGa3(s) = UGa2(s) + Ga(g) were computed and subsequently Gibbs free energies of formation of U3Ga5(s) and UGa3(s) were deduced as ΔfGTo U3Ga5(s) (±5.5) = -352.4 + 0.133 T(K) (kJ mol-1) (1208-1366 K) and ΔfGTo UGa3(s) (±3.8) = -191.9 + 0.082 T(K) (kJ mol-1) (1133-1338 K). The Gibbs free energy of formation of U3Ga5(s) is being reported for the first time.
Cacho, J I; Campillo, N; Viñas, P; Hernández-Córdoba, M
2015-02-06
A method using direct sample introduction (DSI) coupled to gas chromatography-mass spectrometry (GC-MS) is developed for the determination of six phthalate esters (dimethyl, diethyl, dibutyl, butylbenzyl, diethylhexyl and dioctyl phthalate) in cleaning products. The different variables involved in the DSI step, including venting time and temperature, vaporisation time and temperature, injector heating temperature and gas flow rate and pressure, were evaluated and optimised using Taguchi orthogonal arrays. The proposed method, using calibration against methanolic standards, showed good linearity in the 0.05-15 μg g(-1) range and good repeatability, with RSD values ranging from 3.5% to 5.7%. Quantification limits between 0.010 and 0.041 μg g(-1), depending on the compound, were attained, while recovery assays provided values from 83% to 115%. Twenty-seven cleaning products were analysed using the DSI-GC-MS method, being four phthalates (dimethyl, diethyl, dibutyl and diethylhexyl phthalate) found in fourteen of them at concentration levels in the 0.1-21 μg g(-1) range. Compared with the most common GC injection technique, which uses the split/splitless injector, the proposed DSI procedure provided larger peak areas and lower detection limits, as result of the greater injected volume and reduction in noise. Copyright © 2014 Elsevier B.V. All rights reserved.
Lynch, Mark; Sriprasad, Seshadri; Subramonian, Kesavapillai; Thompson, Peter
2010-01-01
INTRODUCTION Intractable haemorrhage after endoscopic surgery, including transurethral resection of the prostate (TURP) and photoselective vaporisation of the prostate (PVP), is uncommon but a significant and life-threatening problem. The knowledge and technical experience to deal with this complication may not be wide-spread among urologists and trainees. We describe our series of TURPs and PVPs and the incidence of postoperative bleeding requiring intervention. PATIENTS AND METHODS We retrospectively reviewed 437 TURPs and 590 PVPs over 3 years in our institution. We describe the conservative, endoscopic and open prostatic packing techniques used for patients who experienced postoperative bleeding. RESULTS Of 437 TURPs, 19 required endoscopic intervention for postoperative bleeding. Of 590 PVPs, two patients were successfully managed endoscopically for delayed haemorrhage at 7 and 13 days post-surgery, respectively. In one TURP and one PVP patient, endoscopic management was insufficient to control postoperative haemorrhage and open exploration and packing of the prostatic cavity was performed. CONCLUSIONS Significant bleeding after endoscopic prostatic surgery is still a potentially life-threatening complication. Prophylactic measures have been employed to reduce peri-operative bleeding but persistent bleeding post-endoscopic prostatic surgery should be treated promptly to prevent the risk of rapid deterioration. We demonstrated that the technique of open prostate packing may be life-saving. PMID:20522311
Bell, Stephanie; Dean, Judith; Gilks, Charles; Boyd, Mark A; Fitzgerald, Lisa; Mutch, Allyson; Baker, Peter; Neilsen, Graham; Gartner, Coral E
2017-07-18
Smoking is a leading cause of morbidity and premature mortality among people living with HIV (PLHIV), who have high rates of tobacco smoking. Vaporised nicotine products (VNPs) are growing in popularity as a quit aid and harm reduction tool. However, little is known about their acceptability and use among PLHIV. Using a pragmatic, uncontrolled, mixed methods design this exploratory clinical trial aims to examine the feasibility of conducting a powered randomised clinical trial of VNPs as a smoking cessation and harm reduction intervention among vulnerable populations, such as PLHIV who smoke tobacco. Convenience sampling and snowball methods will be used to recruit participants (N = 30) who will receive two VNPs and up to 12 weeks' supply of nicotine e-liquid to use in a quit attempt. Surveys will be completed at weeks 0 (baseline), 4, 8, 12 (end of treatment) and 24 (end of the study) and qualitative interviews at weeks 0 and 12. As far as we are aware, this feasibility study is the first to trial VNPs among PLHIV for smoking cessation. If feasible and effective, this intervention could offer a new approach to reducing the high burden of tobacco-related disease among PLHIV and other vulnerable populations.
Informal Photochemistry Conference (XVIIIth)
1990-02-15
Shen and James M. Farrar (Rochester) 22. Photochemistry of NF 2 in the 260 nm Band H . Helvajian , R.F. Heidner Il, J.S. Holloway and J.B. Koffend...Monica, CA 90405 January 9-13, 1989 Organizers: R.A. Beaudet, H . Reisler and C. Wittig Department of Chemistry University of Southern California Los...Collision Reactions of Excited Calcium Produced by Laser Vaporisation 2:00 - 2:30 Curt Wittig (USC) H -Atom Reactions in Complexes 2:30 - 2:50 William
High temperature investigation of the solid/liquid transition in the PuO2-UO2-ZrO2 system
NASA Astrophysics Data System (ADS)
Quaini, A.; Guéneau, C.; Gossé, S.; Sundman, B.; Manara, D.; Smith, A. L.; Bottomley, D.; Lajarge, P.; Ernstberger, M.; Hodaj, F.
2015-12-01
The solid/liquid transitions in the quaternary U-Pu-Zr-O system are of great interest for the analysis of core meltdown accidents in Pressurised Water Reactors (PWR) fuelled with uranium-dioxide and MOX. During a severe accident the Zr-based cladding can become completely oxidised due to the interaction with the oxide fuel and the water coolant. In this framework, the present analysis is focused on the pseudo-ternary system UO2-PuO2-ZrO2. The melting/solidification behaviour of five pseudo-ternary and one pseudo-binary ((PuO2)0.50(ZrO2)0.50) compositions have been investigated experimentally by a laser heating method under pre-set atmospheres. The effects of an oxidising or reducing atmosphere on the observed melting/freezing temperatures, as well as the amount of UO2 in the sample, have been clearly identified for the different compositions. The oxygen-to-metal ratio is a key parameter affecting the melting/freezing temperature because of incongruent vaporisation effects. In parallel, a detailed thermodynamic model for the UO2-PuO2-ZrO2 system has been developed using the CALPHAD method, and thermodynamic calculations have been performed to interpret the present laser heating results, as well as the high temperature behaviour of the cubic (Pu,U,Zr)O2±x-c mixed oxide phase. A good agreement was obtained between the calculated and experimental data points. This work enables an improved understanding of the major factors relevant to severe accident in nuclear reactors.
Calculations of Asteroid Impacts into Deep and Shallow Water
NASA Astrophysics Data System (ADS)
Gisler, Galen; Weaver, Robert; Gittings, Michael
2011-06-01
Contrary to received opinion, ocean impacts of small (<500 m) asteroids do not produce tsunamis that lead to world-wide devastation. In fact the most dangerous features of ocean impacts, just as for land impacts, are the atmospheric effects. We present illustrative hydrodynamic calculations of impacts into both deep and shallow seas, and draw conclusions from a parameter study in which the size of the impactor and the depth of the sea are varied independently. For vertical impacts at 20 km/s, craters in the seafloor are produced when the water depth is less than about 5-7 times the asteroid diameter. Both the depth and the diameter of the transient crater scale with the asteroid diameter, so the volume of water excavated scales with the asteroid volume. About a third of the crater volume is vaporised, because the kinetic energy per unit mass of the asteroid is much larger than the latent heat of vaporisation of water. The vaporised water carries away a considerable fraction of the impact energy in an explosively expanding blast wave which is responsible for devastating local effects and may affect worldwide climate. Of the remaining energy, a substantial portion is used in the crown splash and the rebound jet that forms as the transient crater collapses. The collapse and rebound cycle leads to a propagating wave with a wavelength considerably shorter than classical tsunamis, being only about twice the diameter of the transient crater. Propagation of this wave is hindered somewhat because its amplitude is so large that it breaks in deep water and is strongly affected by the blast wave's perturbation of the atmosphere. Even if propagation were perfect, however, the volume of water delivered per metre of shoreline is less than was delivered by the Boxing Day 2004 tsunami for any impactor smaller than 500 m diameter in an ocean of 5 km depth or less. Near-field effects are dangerous for impactors of diameter 200 m or greater; hurricane-force winds can extend tens of kilometers from the impact point, and fallout from the initial splash can be extremely violent. There is some indication that near-field effects are more severe if the impact occurs in shallow water.
NASA Astrophysics Data System (ADS)
Hermanns, Thomas; Sulser, Tullio; Hefermehl, Lukas J.; Strebel, Daniel; Michel, Maurice-Stephan; Müntener, Michael; Meier, Alexander H.; Seifert, Hans-Helge
2009-02-01
It has recently been shown that laser fibre deterioration leads to a significant decrease of power output during 80 W potassium titanyl phosphate (KTP) laser vaporisation (LV) of the prostate. This decrease results in inefficient vaporisation especially towards the end of the procedure. For the new 120 W lithium-triborate (LBO) High Performance System (HPS) laser not only higher power but also changes in beam characteristics and improved fibre quality have been advertised. However, high laser power has been identified as a risk factor for laser fibre degradation. Between July and September 2008 25 laser fibres were investigated during routine 120 W LBO-LV in 20 consecutive patients. Laser beam power was measured at baseline and after the application of every 25 kJ during the LV procedure. Postoperatively, the surgeon subjectively rated the performance of the respective fibre on a scale from 1 to 4 (1 indicating perfect and 4 insufficient performance). Additionally, microscopic examination of the fibre tip was performed. Median energy applied was 212 kJ. Changes of power output were similar for all fibres. Typically, a steep decrease of power output within the first 50 kJ was followed by a continuous mild decrease until the end of the procedure. After the application of 50 kJ the median power output was 63% (58-73% interquartile range) of the baseline value. The median power output at the end of the 275 kJ-lifespan of the fibres was 42% (40-47%). The median surgeons' rating of the overall performance of the laser fibres was 2 and the median estimated final decrease of power output 60%. Some degree of degradation at the emission window was microscopically detectable in all cases after the procedure. However, even after the application of 275 kJ, these structural changes were only moderate. Minor degradation of the laser fibre was associated with a significant decrease of power output during 120 W LBO-LV. However, following an early, steep decrease, power output remained relatively constant on a medium level for the rest of the fibre's lifespan. The subjective rating by the surgeons is in accordance with these findings. Improved properties of the LBO laser and enhanced fibre quality resulted in an only moderate decrease of power output which allowed for a consistently effective performance.
Characterisation of diesel particulate emission from engines using commercial diesel and biofuels
NASA Astrophysics Data System (ADS)
Ajtai, T.; Pintér, M.; Utry, N.; Kiss-Albert, G.; Gulyás, G.; Pusztai, P.; Puskás, R.; Bereczky, Á.; Szabados, Gy.; Szabó, G.; Kónya, Z.; Bozóki, Z.
2016-06-01
In this paper, the number concentration and the size distribution of diluted diesel exhaust particulate matter were measured at three different engine operating points in the speed-load range of the engine as follows: 1600 rpm; 50% load, 1900 rpm; 25% load, 1900 rpm; 75% load, adopted from the UN ECE Vehicle Regulation no. 49 (Revision 2) test protocol using pure diesel and biodiesel fuels, as well as their controlled blends. The emitted particulate assembly had lognormal size distribution in the accumulation mode regardless of the engine operational condition and the type of fuel. The total number and volume concentration emitted by the diesel engine decreased with increasing revolution per minute and rated torque in case of all the fuel types. The mixing ratio of the fuels did not linearly affect the total emission but had a minimum at 75% biodiesel content. We also studied the thermal evolution of the emitted particulates using a specially designed thermodenuder (TD) heated at specific temperatures (50 °C, 120 °C, and 250 °C). The first transition, when the temperature was increased from 50 °C to 120 °C resulted in lower number concentrations with small relative shifts of the peak position. However, in case of the second transition, when the temperature reached 250 °C the individual volatile particulates adsorbed onto the surface of soot particles were completely or partly vaporised resulting in lower total number concentrations with a substantial shift in peak position.
[External sphincterotomy using bipolar vaporisation in saline. First results].
Even, L; Guillotreau, J; Mingat, N; Castel-Lacanal, E; Braley, E; Malavaud, B; Marque, P; Rischmann, P; Gamé, X
2012-07-01
The aim of this study was to assess the feasibility, efficacy and tolerance of external urethral sphincter vaporization in saline for treating detrusor-sphincter dyssynergia. Between 2009 and 2011 a monocentric prospective study of ten men mean age 58±9 years with neurogenic detrusor-sphincter dyssynergia was carried out. Preoperative evaluation included kidney ultrasound scan, 24-hour creatinine clearance, urodynamics, retrograde and voiding urethrocystography and an at least 6 months temporary stent sphincterotomy. Postoperative assessment was composed of an ultrasound scan post-void residual volume measurement when the urethral catheter were removed and 1 year after the procedure, a retrograde and voiding urethrocystography at 3 months and a flexible cystoscopy at 1 year. At the catheter removal, eight patients emptied their bladder at completion, a supra-pubic catheter was temporary left in one case and a patient had a permanent urinary retention. For a mean follow-up of 22±11 months, eight patients emptied their bladder at completion and two had a complete urinary retention related to a detrusor underactivity. An orchitis occurred in one case 1 month after the procedure and an urethral stricture in four cases in 12.75±5.68 months on average. External urethral sphincter vaporisation saline was feasible and efficient for treating detrusor-sphincter dyssynergia but was associated with a high risk of urethral stricture. Copyright © 2012 Elsevier Masson SAS. All rights reserved.
Bell, Stephanie K; Mena, Gabriela; Dean, Judith; Boyd, Mark; Gilks, Charles; Gartner, Coral
2017-08-01
Tobacco smoking is a major cause of morbidity and mortality among people living with HIV (PLHIV). Due to the limited success of standard abstinence-focused smoking cessation strategies in this population, there is growing interest in tobacco harm reduction (THR) approaches as an additional strategy to address these high smoking rates. This study explored the attitudes of health practitioners who provide healthcare to PLHIV towards THR. 179 Australian health practitioners who provide healthcare to PLHIV completed an online survey that measured their attitudes towards THR approaches, including switching from cigarettes to e-cigarettes or vaporised nicotine products (VNPs). Respondents supported the concept of THR but were undecided on the role of VNPs. Respondents most commonly reported 'don't know' or 'undecided' responses to statements regarding VNPs. More respondents, however, agreed than disagreed that switching from smoking to long-term vaping could reduce risk (36% and 22% respectively) and be an effective strategy to help PLHIV to quit smoking (37% agree and 17% disagree). Only a minority of respondents (20%) agreed that VNPs are too harmful to recommend to patients, however around half (53%) were undecided. Despite supporting the principle of THR, health practitioners may require more evidence and knowledge about VNPs before being willing to consider them as a suitable intervention strategy. Copyright © 2017 Elsevier B.V. All rights reserved.
Cannabis smoke condensate III: the cannabinoid content of vaporised Cannabis sativa.
Pomahacova, B; Van der Kooy, F; Verpoorte, R
2009-11-01
Cannabis sativa is a well-known recreational drug and, as such, a controlled substance of which possession and use are illegal in most countries of the world. Due to the legal constraints on the possession and use of C. sativa, relatively little research on the medicinal qualities of this plant has been conducted. Interest in the medicinal uses of this plant has, however, increased in the last decades. The methods of administration for medicinal purposes are mainly through oral ingestion, smoking, and nowadays also inhalation through vaporization. During this study the commercially available Volcano vaporizing device was compared with cannabis cigarette smoke. The cannabis smoke and vapor (obtained at different temperatures) were quantitatively analyzed by high-performance liquid chromatography (HPLC). In addition, different quantities of cannabis material were also tested with the vaporizer. The cannabinoids:by-products ratio in the vapor obtained at 200 degrees C and 230 degrees C was significantly higher than in the cigarette smoke. The worst ratio of cannabinoids:by-products was obtained from the vaporized cannabis sample at 170 degrees C.
Broadband Ftmw Spectroscopy of the Urea-Argon and Thiourea-Argon Complexes
NASA Astrophysics Data System (ADS)
Medcraft, Chris; Bittner, Dror M.; Cooper, Graham A.; Mullaney, John C.; Walker, Nick
2017-06-01
The rotational spectra complexes of argon-urea, argon-thiourea and water-thiourea have been measured by chirped-pulse Fourier transform microwave spectroscopy from 2-18.5 GHz. The sample was produced via laser vaporisation of a rod containing copper and the organic sample as a stream of argon was passed over the surface and subsequently expanded into the vacuum chamber cooling the sample. Argon was found to bind to π system of the carbonyl bond for both the urea and thiourea complexes.
Reactions of Ions with Ionic Liquid Vapors by Selected-Ion Flow Tube Mass Spectrometry
2011-03-04
Internet at http://pubs.acs.org. References (1) Emel’yanenko, V. N.; Verevkin, S. P.; Heintz, A.; Corfield, J.-A.; Deyko, A.; Lovelock , K. R. J...Spectrometry, and ab Initio Calculations J. Phys. Chem. B 2008, 112, 11734-11742. (2) Lovelock , K. R. J.; Deyko, A.; Licence, P.; Jones, R. G. Vaporisation of...Licence, P.; Lovelock , K. R. J.; Satterly, C. J.; Villar-Garcia, I. J. Vapourisation of ionic liquids PCCP 2007, 9, 982-990. (14) Chiu, Y.-H
The UK Ion Thruster System and a Proposed Future Programme.
1977-05-01
design and constructional features 13 1.2.3 The hollow cathode assembly 14 1.2.4 Isolators 16 1.2.5 Vaporisers 17 1.2.6 The neutraliser system 19 1.2.7... constructed and integrated with the thrus ter by MSDS Ltd)3, and is now undergoing modifications in light of the more recent experience gained in operating...measurements of virtuall y all the materials emitted by the thruster. The latter requirement has necessitated the construction of a complex system of probes
Khenissi, Latifa; Covey-Crump, Gwen; Knowles, Toby G; Murrell, Joanna
2017-05-01
To investigate whether the use of a heat and moisture exchanger (HME) preserves body temperature in dogs weighing <10 kg anaesthetised for magnetic resonance imaging (MRI). Prospective, randomised, clinical trial. Thirty-one client-owned dogs. Dogs were assigned randomly to a treatment group [HME (n = 16) or no HME (n = 15)]. Dogs were pseudorandomised according to the premedication they were administered, either dexmedetomidine or no dexmedetomidine. Induction agents were not standardised. General anaesthesia was maintained with isoflurane vaporised in 100% oxygen delivered using a T-piece and a fresh gas flow of 600 mL kg -1 minute -1 . Rectal temperature was measured before premedication (T1), after induction (T2), before moving to the MRI unit (T3) and at the end of the MRI scan (T4). Ambient temperatures were measured in the induction room, outside and inside the MRI unit. Data were analysed using a general linear model with T4 as the outcome variable. Linear correlations were performed between T1, T2, T3 and T4, and variables that predicted T4 were investigated. Sex, age and body mass were not significantly different between groups. There were no significant differences in rectal temperature between groups at any time point (group with HME at the end of MRI = 36.3 ± 1.1 °C; group with no HME at the end of MRI = 36.2 ± 1.4 °C) but at the end of the MRI, dogs administered dexmedetomidine (36.6 ± 0.7 °C) had a higher rectal temperature compared with dogs not administered dexmedetomidine (35.9 ± 1.6 °C) for premedication. Rectal temperature varied directly with ambient temperature in MRI scanning room and inversely with anaesthetic duration. Using an HME did not alter body temperature in dogs weighing <10 kg undergoing an MRI, but including dexmedetomidine in the premedication regimen seemed to preserve the body temperature during anaesthesia. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
Yang, Yu-Chiao; Lin, Pei-Hui; Wei, Ming-Chi
2017-08-01
Among active components in Rabdosia rubescens, oridonin has been considered a key component and the most valuable compound because it has a wide range of activities beneficial to human health. To produce a high-quality oridonin extract, an alternative hyphenated procedure involving an ultrasound-assisted and supercritical carbon dioxide (HSC-CO 2 ) extraction method to extract oridonin from R. rubescens was developed in this study. Fictitious solubilities of oridonin in supercritical CO 2 (SC-CO 2 ) with ultrasound assistance were measured by using the dynamic method at temperatures ranging from 305.15 K to 342.15 K over a pressure range of 11.5 to 33.5 MPa. Fictitious solubilities of oridonin at different temperatures and pressures were over the range of 2.13 × 10 -6 to 10.09 × 10 -6 (mole fraction) and correlated well with the density-based models, including the Bartle model, the Chrastil model, the Kumar and Johnston model and the Mendez-Santiago and Teja model, with overall average absolute relative deviations (AARDs) of 6.29%, 4.39%, 3.12% and 5.07%, respectively. Oridonin exhibits retrograde solubility behaviour in the supercritical state. Fictitious solubility data were further determined and obtained a good fit with four semi-empirical models. Simultaneously, the values of the total heat of solution, vaporisation and solvation of oridonin were estimated. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
Accelerator-based chemical and elemental analysis of atmospheric aerosols
NASA Astrophysics Data System (ADS)
Mentes, Besim
Aerosol particles have always been present in the atmosphere, arising from natural sources. But it was not until recently when emissions from anthropogenic (man made) sources began to dominate, that atmospheric aerosols came into focus and the aerosol science in the environmental perspective started to grow. These sources emit or produce particles with different elemental and chemical compositions, as well as different sizes of the individual aerosols. The effects of increased pollution of the atmosphere are many, and have different time scales. One of the effects known today is acid rain, which causes problems for vegetation. Pollution is also a direct human health risk, in many cities where traffic driven by combustion engines is forbidden at certain times when the meteorological conditions are unfavourable. Aerosols play an important role in the climate, and may have both direct and indirect effect which cause cooling of the planet surface, in contrast to the so-called greenhouse gases. During this work a technique for chemical and elemental analysis of atmospheric aerosols and an elemental analysis methodology for upper tropospheric aerosols have been developed. The elemental analysis is performed by the ion beam analysis (IBA) techniques, PIXE (elements heavier than Al). PESA (C, N and O), cPESA (H) and pNRA (Mg and Na). The chemical speciation of atmospheric aerosols is obtained by ion beam thermography (IBT). During thermography the sample temperature is stepwise increased and the IBA techniques are used to continuously monitor the elemental concentration. A thermogram is obtained for each element. The vaporisation of the compounds in the sample appears as a concentration decrease in the thermograms at characteristic vaporisation temperatures (CVTs). Different aspects of IBT have been examined in Paper I to IV. The features of IBT are: almost total elemental speciation of the aerosol mass, chemical speciation of the inorganic compounds, carbon content obtained as volatile and non-volatile fractions, analysis of acidic aerosols is possible, aerosols can be size-fractionated using a cascade impactor as collection device, total analysis time for a sample is around 45 min, the sample mass load is from around 1 to 30 μg/cm2. An intercomparison of IBT and ion chromatography (IC) when a DMPS system was used as a reference instrument has been performed (Paper IV). Ions of K, Na, SO4, NO3 and NH4 were determined and quantified by both IBT and IC. The intercomparison showed that the procedure used in IBT does not suffer from any selective losses, especially not from the NO3 and NH4 compounds, which exhibit an appreciable interaction with the gas phase as NH3 and HNO3. An impactor-based aerosol sampler for upper tropospheric conditions has been developed (Paper V). Despite the low aerosol concentration at that altitude the sulphur concentration can be measured, with a detection limit of 1 ng/m 3 for one hour sampling by optimising parameters in the use of PIXE analysis.
LPG as a Fuel for Diesel Engines-Experimental Investigations
NASA Astrophysics Data System (ADS)
Cristian Nutu, Nikolaos; Pana, Constantin; Negurescu, Niculae; Cernat, Alexandru; Mirica, Ionel
2017-10-01
The main objective of the paper is to reduce the pollutant emissions of a compression ignition engine, fuelling the engine with liquefied petroleum gas (LPG), aiming to maintain the energetic performances of the engine. To optimise the engine operation a corelation between the substitute ratio of the diesel fuel with LPG and the adjustments for the investigated regimens must be made in order to limit the maximum pressure and smoke level, knock and rough engine functioning, fuel consumption and the level of the pollutant emissions. The test bed situated in the Thermotechnics, Engines, Thermal Equipments and Refrigeration Instalations Department was adapted to be fuelled with liquefied petroleum gas. A conventional LPG fuelling instalation was adopted, consisting of a LPG tank, a vaporiser, conections between the tank and the vaporiser and a valve to adjust the gaseous fuel flow. Using the diesel-gas methode, in the intake manifold of the engine is injected LPG in gaseous aggregation state and the airr-LPG homogeneous mixture is ignited from the flame appeared in the diesel fuel sprays. To maintain the engine power at the same level like in the standard case of fuelling only with diesel fuel, for each investigated operate regimen the diesel fuel dose was reduced, being energetically substituted with LPG. The engine used for experimental investigations is a turbocharged truck diesel engine with a 10.34 dm3 displacement. The investigated working regimen was 40% load and 1750 rpm and the energetic substitute ratios of the diesel fuel with LPG was situated between [0-25%].
Current role of lasers in the treatment of benign prostatic hyperplasia (BPH).
Kuntz, Rainer M
2006-06-01
Evaluate the current role of lasers in the treatment of benign prostatic hyperplasia (BPH). The results of a MEDLINE search for randomised trials and case series of the last 5 yr and published review articles were analysed for the safety and efficacy of neodymium:yttrium aluminum garnet (Nd:YAG), potassium-titanyl-phosphate (KTP), and holmium (Ho):YAG laser prostatectomy. The analysis includes 12 reports on randomised clinical trials, 2 comparative studies, 10 review articles, and a total of >5000 patients. Laser treatment of BPH has evolved from coagulation to enucleation. Blood loss is significantly reduced compared with transurethral resection and open prostatectomy. Visual laser ablation of the prostate and interstitial laser coagulation cause coagulative necrosis with secondary ablation. Long postoperative catheterisation, unpredictable outcomes, and high reoperation rates have restricted the use of these techniques. Ablative/vaporising techniques have become popular again with the marketing of new high-powered 80-W KTP and 100-W Ho lasers. Vaporisation immediately removes obstructing tissue. Short-term results are promising, but large series, long-term results, and randomised trials are lacking. Holmium laser enucleation (HoLEP) allows whole lobes of the prostate to be removed, mimicking the action of the index finger in open prostatectomy. Prostates of all sizes can be operated on. It is at least as safe and effective as transurethral resection of the prostate and open prostatectomy, with significantly lower morbidity. It is the only laser procedure that provides a specimen for histologic evaluation. HoLEP appears to be a size-independent new "gold standard" in the surgical treatment of BPH.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vidal, Judith C; Mohan, Gowtham; Venkataraman, Mahesh
A novel ternary eutectic salt mixture for high-temperature sensible heat storage, composed of sodium chloride, potassium chloride and magnesium chloride (NaKMg-Cl) was developed based on a phase diagram generated with FactSage(R). The differential scanning calorimetry (DSC) technique was used to experimentally validate the predicted melting point of the ternary eutectic composition, which was measured as 387 degrees C, in good agreement with the prediction. The ternary eutectic was compared to two binary salts formulated based on prediction of the eutectic composition by FactSage, but unfortunately DSC measurements showed that neither binary salt composition was eutectic. Nonetheless, the measured thermo-physical propertiesmore » of the ternary and the two binary mixtures are compared. Liquid heat capacities of both the ternary and binary salts were determined by using DSC with sapphire as the standard reference. The average heat capacity of the ternary mixture was recorded as 1.18 J g-1 K-1. The mass loss of the molten eutectic salts was studied up to 1000 degrees C using a thermogravimetric analyser in nitrogen, argon and air. The results showed a significant mass loss due to vaporisation in an open system, particularly above 700 degrees C. However, simulation of mass loss in a closed system with an inert cover gas indicates storage temperatures above 700 degrees C may be feasible, and highlights the importance of the design of the storage tank system. In terms of storage material cost, the NaKMg-Cl mixture is approximately 4.5 USD/kWh, which is 60% cheaper than current state-of-the-art nitrate salt mixtures.« less
NASA Astrophysics Data System (ADS)
Gkinis, Vasileios; Holme, Christian; Morris, Valerie; Thayer, Abigail Grace; Vaughn, Bruce; Kjaer, Helle Astrid; Vallelonga, Paul; Simonsen, Marius; Jensen, Camilla Marie; Svensson, Anders; Maffrezzoli, Niccolo; Vinther, Bo; Dallmayr, Remi
2017-04-01
We present a performance comparison study between two state of the art Cavity Ring Down Spectrometers (Picarro L2310-i, L2140-i). The comparison took place during the Continuous Flow Analysis (CFA) campaign for the measurement of the Renland ice core, over a period of three months. Instant and complete vaporisation of the ice core melt stream, as well as of in-house water reference materials is achieved by accurate control of microflows of liquid into a homemade calibration system by following simple principles of the Hagen-Poiseuille law. Both instruments share the same vaporisation unit in a configuration that minimises sample preparation discrepancies between the two analyses. We describe our SMOW-SLAP calibration and measurement protocols for such a CFA application and present quality control metrics acquired during the full period of the campaign on a daily basis. The results indicate an unprecedented performance for all 3 isotopic ratios (δ2H, δ17O, δ18O ) in terms of precision, accuracy and resolution. We also comment on the precision and accuracy of the second order excess parameters of HD16O and H217O over H218O (Dxs, Δ17O ). To our knowledge these are the first reported CFA measurements at this level of precision and accuracy for all three isotopic ratios. Differences on the performance of the two instruments are carefully assessed during the measurement and reported here. Our quality control protocols extend to the area of low water mixing ratios, a regime in which often atmospheric vapour measurements take place and Cavity Ring Down Analysers show a poorer performance due to the lower signal to noise ratios. We address such issues and propose calibration protocols from which water vapour isotopic analyses can benefit from.
Whitty, Jennifer A; Crosland, Paul; Hewson, Kaye; Narula, Rajan; Nathan, Timothy R; Campbell, Peter A; Keller, Andrew; Scuffham, Paul A
2014-03-01
To compare the costs of photoselective vaporisation (PVP) and transurethral resection of the prostate (TURP) for management of symptomatic benign prostatic hyperplasia (BPH) from the perspective of a Queensland public hospital provider. A decision-analytic model was used to compare the costs of PVP and TURP. Cost inputs were sourced from an audit of patients undergoing PVP or TURP across three hospitals. The probability of re-intervention was obtained from secondary literature sources. Probabilistic and multi-way sensitivity analyses were used to account for uncertainty and test the impact of varying key assumptions. In the base case analysis, which included equipment, training and re-intervention costs, PVP was AU$ 739 (95% credible interval [CrI] -12 187 to 14 516) more costly per patient than TURP. The estimate was most sensitive to changes in procedural costs, fibre costs and the probability of re-intervention. Sensitivity analyses based on data from the most favourable site or excluding equipment and training costs reduced the point estimate to favour PVP (incremental cost AU$ -684, 95% CrI -8319 to 5796 and AU$ -100, 95% CrI -13 026 to 13 678, respectively). However, CrIs were wide for all analyses. In this cost minimisation analysis, there was no significant cost difference between PVP and TURP, after accounting for equipment, training and re-intervention costs. However, PVP was associated with a shorter length of stay and lower procedural costs during audit, indicating PVP potentially provides comparatively good value for money once the technology is established. © 2013 The Authors. BJU International © 2013 BJU International.
Fast and "green" method for the analytical monitoring of haloketones in treated water.
Serrano, María; Silva, Manuel; Gallego, Mercedes
2014-09-05
Several groups of organic compounds have emerged as being particularly relevant as environmental pollutants, including disinfection by-products (DBPs). Haloketones (HKs), which belong to the unregulated volatile fraction of DBPs, have become a priority because of their occurrence in drinking water at concentrations below 1μg/L. The absence of a comprehensive method for HKs has led to the development of the first method for determining fourteen of these species. In an effort to miniaturise, this study develops a micro liquid-liquid extraction (MLLE) method adapted from EPA Method 551.1. In this method practically, the whole extract (50μL) was injected into a programmed temperature vaporiser-gas chromatography-mass spectrometer in order to improve sensitivity. The method was validated by comparing it to EPA Method 551.1 and showed relevant advantages such as: lower sample pH (1.5), higher aqueous/organic volume ratio (60), lower solvent consumption (200μL) and fast and cost-saving operation. The MLLE method achieved detection limits ranging from 6 to 60ng/L (except for 1,1,3-tribromo-3-chloroacetone, 120ng/L) with satisfactory precision (RSD, ∼6%) and high recoveries (95-99%). An evaluation was carried out of the influence of various dechlorinating agents as well as of the sample pH on the stability of the fourteen HKs in treated water. To ensure the HKs integrity for at least 1 week during storage at 4°C, the samples were acidified at pH ∼1.5, which coincides with the sample pH required for MLLE. The green method was applied to the speciation of fourteen HKs in tap and swimming pool waters, where one and seven chlorinated species, respectively, were found. The concentration of 1.1-dichloroacetone in swimming pool water increased ∼25 times in relation to tap water. Copyright © 2014 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Borets-Pervak, I. Yu; Vorob'ev, V. S.
1995-04-01
An analysis is made of a model of the formation of a surface laser plasma which takes account of the heating and vaporisation of thermally insulated surface microdefects. This model is used in an interpretation of experiments in which such a plasma has been formed by irradiation of a titanium target with microsecond CO2 laser pulses. A comparison with the experimental breakdown intensities is used to calculate the average sizes of microdefects and their concentration: the results are in agreement with the published data. The dependence of the delay time of plasma formation on the total energy in a laser pulse is calculated.
THE ROTATIONAL SPECTRUM OF THE UREA\\cdot\\cdot\\cdotISOCYANIC ACID COMPLEX
NASA Astrophysics Data System (ADS)
Mullaney, John C.; Medcraft, Chris; Walker, Nick; Legon, Anthony; Lewis-Borrell, Luke; Golding, Bernard T.
2016-06-01
A dimer of urea and isocyanic acid has been generated and observed in the gas phase. The complex was generated by laser vaporisation of a rod target containing urea and copper in a 1:1 ratio, then cooled in a supersonic expansion. Six isotopologues of the complex have been characterised using a chirped pulse Fourier-transform microwave spectrometer in the frequency range 6.5-18.5 GHz. The spectra have been fitted to the Hamiltonian for an asymmetric rotor using PGOPHER. Data obtained from the 13C and 15N isotopologues confirms that all nitrogen atoms are close to the a intertial axis while the carbon atoms are not. A tentative structure will be presented.
Broadband Ftmw Spectroscopy of 2-METHYLIMIDAZOLE and Complexes with Water and Argon
NASA Astrophysics Data System (ADS)
Medcraft, Chris; Heitkämper, Juliane; Mullaney, John C.; Walker, Nick
2017-06-01
The rotational spectrum of 2-methylimidazole has been measured using laser ablation chirped-pulse Fourier transform microwave spectroscopy from 2-18.5 GHz. 2-methylimidazole was laser vaporised then entrained within an argon buffer gas undergoing supersonic expansion allowing for efficient rotational cooling. Carbon-13 and nitrogen-15 isotopologues were measured in natural abundance and substitution coordinates have been determined. The barrier to internal rotation of the methyl group was found to be 122.697(20) cm^{-1}. Nuclear quadropole coupling constants for the two nitrogen nuclei were determined via a rigid rotor fit of the A internal rotor state. Complexes with water and argon were also observed and fit in a similar way.
NASA Astrophysics Data System (ADS)
Forsythe, N. D.; Fowler, H.; Pritchard, D.
2016-12-01
High mountain Asia (HMA) constitutes one the key "water towers of the world", giving rise to river basins whose resources support hundreds of millions of people. This area will experience rapid demographic growth and socio-economic development for the next few decades compounding pressure on resource managements systems from inevitable climate change. In order to develop climate services to support water resources planning and facilitate adaptive capacity building, it is essential to critically characterise the skill and biases of the evaluation (reanalysis-driven) and control (historical period) components of presently available regional climate model (RCM) experiments. For mountain regions in particular, the ability of RCMs to reasonably reproduce the influence of complex topography, through lapse rates and orographic forcing, on sub-regional climate - notably temperature and precipitation - must be assessed in detail. HMA falls within the South Asia domain of the Coordinated Regional Downscaling Experiment (CORDEX) initiative. Multiple international modelling centres have contributed RCM experiments for the CORDEX South Asia domain. This substantial multi-model ensemble provides a valuable opportunity to explore the spread in model skill at simulation of key characteristics of the present HMA climate. This study focuses geographically on the northwest Upper Indus basin (NW UIB) which covers the bulk of the Karakoram range. Within this subdomain we use climatologies derived from local observations and meteorological reanalyses (ERA-Interim, NASA MERRA-2, HAR)as benchmarks for inter-comparison of individual CORDEX South Asia ensemble members skill in reproducing seasonality and spatial gradients (orographic precipitation profile, temperature lapse rates). Validation of individual CORDEX South Asia ensemble members to this level of detail is indispensable because discontinuities - e.g. differences in latent heat regimes (fusion versus vaporisation) - abound in mountain environments. These discontinuities may undermine widely used statistical approaches (e.g. change factors) used for downscaling and bias correction of future climate projections to locally observed conditions.
Spatial Distributions of Metal Atoms During Carbon SWNTs Formation: Measurements and Modelling
NASA Technical Reports Server (NTRS)
Cau, M.; Dorval, N.; Attal-Tretout, B.; Cochon, J. L.; Loiseau, A.; Farhat, S.; Hinkov, I.; Scott, C. D.
2004-01-01
Experiments and modelling have been undertaken to clarify the role of metal catalysts during single-wall carbon nanotube formation. For instance, we wonder whether the metal catalyst is active as an atom, a cluster, a liquid or solid nanoparticle [1]. A reactor has been developed for synthesis by continuous CO2-laser vaporisation of a carbon-nickel-cobalt target in laminar helium flow. The laser induced fluorescence technique [2] is applied for local probing of gaseous Ni, Co and CZ species throughout the hot carbon flow of the target heated up to 3500 K. A rapid depletion of C2 in contrast to the spatial extent of metal atoms is observed in the plume (Fig. 1). This asserts that C2 condenses earlier than Ni and Co atoms.[3, 4]. The depletion is even faster when catalysts are present. It may indicate that an interaction between metal atoms and carbon dimers takes place in the gas as soon as they are expelled from the target surface. Two methods of modelling are used: a spatially I-D calculation developed originally for the arc process [5], and a zero-D time dependent calculation, solving the chemical kinetics along the streamlines [6]. The latter includes Ni cluster formation. The peak of C2 density is calculated close to the target surface where the temperature is the highest. In the hot region, C; is dominant. As the carbon products move away from the target and mix with the ambient helium, they recombine into larger clusters, as demonstrated by the peak of C5 density around 1 mm. The profile of Ni-atom density compares fairly well with the measured one (Fig. 2). The early increase is due to the drop of temperature, and the final decrease beyond 6 mm results from Ni cluster formation at the eutectic temperature (approx.1600 K).
Procida, Giuseppe; Cichelli, Angelo; Lagazio, Corrado; Conte, Lanfranco S
2016-01-15
The volatile fraction of virgin olive oil is characterised by low molecular weight compounds that vaporise at room temperature. In order to obtain an aroma profile similar to natural olfactory perception, the composition of the volatile compounds was determined by applying dynamic headspace gas chromatography, performed at room temperature, with a cryogenic trap directly connected to a gas chromatograph-mass spectrometer system. Samples were also evaluated according to European Union and International Olive Council official methods for sensory evaluation. In this paper, the composition of the volatile fraction of 25 extra virgin olive oils from different regions of Italy was analysed and some preliminary considerations on relationships between chemical composition of volatile fraction and sensory characteristics are reported. Forty-two compounds were identified by means of the particular analytical technique used. All the analysed samples, classified as extra virgin by the panel test, never present peaks whose magnitude is important enough in defected oils. The study was focused on the evaluation of volatile compounds responsible for the positive impact on olive odour properties ('green-fruity' and 'sweet') and olfactory perception. Chemometric evaluation of data, obtained through headspace analysis and the panel test evaluation, showed a correlation between chemical compounds and sensory properties. On the basis of the results, the positive attributes of virgin olive oil are divided into two separated groups: sweet types or green types. Sixteen volatile compounds with known positive impact on odour properties were extracted and identified. In particular, eight compounds seem correlated with sweet properties whereas the green sensation appears to be correlated with eight other different substances. The content of the compounds at six carbon atoms proves to be very important in defining positive attributes of extra virgin olive oils and sensory evaluation. © 2015 Society of Chemical Industry.
NASA Astrophysics Data System (ADS)
Kowalewska, Zofia
2011-07-01
For the first time, high-resolution molecular absorption spectrometry with a high-intensity xenon lamp as radiation source has been applied for the determination of sulphur in crude oil and petroleum products. The samples were analysed as xylene solutions using vaporisation in acetylene-air flame or in an electrothermally heated graphite furnace. The sensitive rotational lines of the CS molecule, belonging to the ∆ν = 0 vibrational sequence within the electronic transition X 1∑ + → A 1П, were applied. For graphite furnace molecular absorption spectrometry, the Pd + Mg organic modifier was selected. Strong interactions with Pd atoms enable easier decomposition of sulphur-containing compounds, likely through the temporal formation of Pd xS y molecules. At the 258.056 nm line, with the wavelength range covering central pixel ± 5 pixels and with application of interactive background correction, the detection limit was 14 ng in graphite furnace molecular absorption spectrometry and 18 mg kg -1 in flame molecular absorption spectrometry. Meanwhile, application of 2-points background correction found a characteristic mass of 12 ng in graphite furnace molecular absorption spectrometry and a characteristic concentration of 104 mg kg -1 in flame molecular absorption spectrometry. The range of application of the proposed methods turned out to be significantly limited by the properties of the sulphur compounds of interest. In the case of volatile sulphur compounds, which can be present in light petroleum products, severe difficulties were encountered. On the contrary, heavy oils and residues from distillation as well as crude oil could be analysed using both flame and graphite furnace vaporisation. The good accuracy of the proposed methods for these samples was confirmed by their mutual consistency and the results from analysis of reference samples (certified reference materials and home reference materials with sulphur content determined by X-ray fluorescence spectrometry).
Pascoe, Claire; Christidis, Daniel; Manning, Todd; Lamb, Benjamin W; Murphy, Declan G; Lawrentschuk, Nathan
2018-05-16
Objective To describe our technique utilising photoselective vaporisation of the bladder (PVB) for the management of haemorrhagic cystitis and initial results of 12 patients. Materials and Method An audit of theatre records of a single surgeon was performed to identify patients who had undergone PVB for management of radiation-cystitis. Rigid cystoscopy was performed. Ureteric catheters were placed and active bleeding sites targeted to optimise vision. Ablation was commenced using the vaporize function. When lasering around delicate structures the coagulation function was used. Ureteric catheters remained in situ for 24h. An 18Fr Foley catheter was placed. When urine output was clear continuous bladder irrigation was ceased. Both uretetric catheters and Foley catheter were removed prior to the 24hour mark. Results 12 patients were identified. 8 had previously required blood transfusion secondary to bladder haemorrhage. 9 were successfully treated and 2 saw improvement in haematuria but required a repeat procedure at 3 weeks post operatively. 4 went on to receive hyperbaric oxygenation as consolidative therapy. 1 patient was unsuccessfully treated and went on to cystectomy. There were no mortalities. No patients sustained bladder perforation or damage to surrounding structures. Conclusion Radiation cystitis can be life threatening and remains a challenge for the urologist with traditional intra-vescical treatments such as aluminium or formalin having variable results. We present an alternate technique using PVB to ablate the bladder mucosa, with good results. Consolidation with hyperbaric oxygen therapy may be considered. Our study is limited by small sample size and the presence of bilateral ureteric catheters leaving the bladder free from urine may impact immediate post operative outcomes. These initial results are promising however further prospective evaluation with a larger cohort and pre and post operative cystograms would enable better evaluation of this technique as a definitive management option for haemorrhagic cystitis. Copyright © 2018. Published by Elsevier Inc.
Electronic cigarette: a possible substitute for cigarette dependence.
Caponnetto, P; Russo, C; Bruno, C M; Alamo, A; Amaradio, M D; Polosa, R
2013-03-01
Cigarette smoking is the leading cause of premature mortality in western countries and it is important for smokers to stop as early as possible. Electronic cigarettes are a popular phenomenon of global proportion. Recent uncontrolled studies, reported that a certain number of smokers have quit using electronic cigarettes. This could hint a role for electronic cigarettes to be used for smoking cessation, and therefore merits further evaluation for this purpose. Besides vaporising nicotine to be inhaled, electronic cigarettes may also provide a coping mechanism for conditioned smoking cues by replacing some of the rituals associated with smoking gestures, and for these reasons cigarette could become a tool--if studied more extensively--in the fight against tobacco-related morbidity and mortality.
[Electronic Cigarettes: Lifestyle Gadget or Smoking Cessation Aid?].
Schuurmans, Macé M
2015-07-01
Electronic cigarettes (e-cigarettes) are vaporisers of liquids often containing nicotine. In the inhaled aerosol carcinogens, ultrafine and metal particles are detected usually in concentrations below those measured in tobacco smoke. Therefore, these products are expected to be less harmful. This has not yet been proven. The long-term safety of e-cigarettes is unknown. Short duration use leads to airway irritation and increased diastolic blood pressure. So far only two randomised controlled trials have investigated efficacy and safety of e-cigarettes for smoking cessation: No clear advantage was shown in comparison to smoking cessation medication. Due to insufficient evidence, e-cigarettes cannot be recommended for smoking cessation. Problematic are the lack of regulation and standardisation of e-cigarette products, which makes general conclusions impossible.
Geiss, Otmar; Bianchi, Ivana; Barrero-Moreno, Josefa
2016-05-01
E-liquids generally contain four main components: nicotine, flavours, water and carrier liquids. The carrier liquid dissolves flavours and nicotine and vaporises at a certain temperature on the atomizer of the e-cigarette. Propylene glycol and glycerol, the principal carriers used in e-liquids, undergo decomposition in contact with the atomizer heating-coil forming volatile carbonyls. Some of these, such as formaldehyde, acetaldehyde and acrolein, are of concern due to their adverse impact on human health when inhaled at sufficient concentrations. The aim of this study was to correlate the yield of volatile carbonyls emitted by e-cigarettes with the temperature of the heating coil. For this purpose, a popular commercial e-liquid was machine-vaped on a third generation e-cigarette which allowed the variation of the output wattage (5-25W) and therefore the heat generated on the atomizer heating-coil. The temperature of the heating-coil was determined by infrared thermography and the vapour generated at each temperature underwent subjective sensorial quality evaluation by an experienced vaper. A steep increase in the generated carbonyls was observed when applying a battery-output of at least 15W corresponding to 200-250°C on the heating coil. However, when considering concentrations in each inhaled puff, the short-term indoor air guideline value for formaldehyde was already exceeded at the lowest wattage of 5W, which is the wattage applied in most 2nd generation e-cigarettes. Concentrations of acetaldehyde in each puff were several times below the short-term irritation threshold value for humans. Acrolein was only detected from 20W upwards. The negative sensorial quality evaluation by the volunteering vaper of the vapour generated at 20W demonstrated the unlikelihood that such a wattage would be realistically set by a vaper. This study highlights the importance to develop standardised testing methods for the assessment of carbonyl-emissions and emissions of other potentially harmful compounds from e-cigarettes. The wide variety and variability of products available on the market make the development of such methods and the associated standardised testing conditions particularly demanding. Copyright © 2016 The Authors. Published by Elsevier GmbH.. All rights reserved.
High-power picosecond laser with 400W average power for large scale applications
NASA Astrophysics Data System (ADS)
Du, Keming; Brüning, Stephan; Gillner, Arnold
2012-03-01
Laser processing is generally known for low thermal influence, precise energy processing and the possibility to ablate every type of material independent on hardness and vaporisation temperature. The use of ultra-short pulsed lasers offers new possibilities in the manufacturing of high end products with extra high processing qualities. For achieving a sufficient and economical processing speed, high average power is needed. To scale the power for industrial uses the picosecond laser system has been developed, which consists of a seeder, a preamplifier and an end amplifier. With the oscillator/amplifier system more than 400W average power and maximum pulse energy 1mJ was obtained. For study of high speed processing of large embossing metal roller two different ps laser systems have been integrated into a cylinder engraving machine. One of the ps lasers has an average power of 80W while the other has 300W. With this high power ps laser fluencies of up to 30 J/cm2 at pulse repetition rates in the multi MHz range have been achieved. Different materials (Cu, Ni, Al, steel) have been explored for parameters like ablation rate per pulse, ablation geometry, surface roughness, influence of pulse overlap and number of loops. An enhanced ablation quality and an effective ablation rate of 4mm3/min have been achieved by using different scanning systems and an optimized processing strategy. The max. achieved volume rate is 20mm3/min.
NASA Astrophysics Data System (ADS)
Federici, Gianfranco; Raffray, A. René
1997-04-01
The transient thermal model RACLETTE (acronym of Rate Analysis Code for pLasma Energy Transfer Transient Evaluation) described in part I of this paper is applied here to analyse the heat transfer and erosion effects of various slow (100 ms-10 s) high power energy transients on the actively cooled plasma facing components (PFCs) of the International Thermonuclear Experimental Reactor (ITER). These have a strong bearing on the PFC design and need careful analysis. The relevant parameters affecting the heat transfer during the plasma excursions are established. The temperature variation with time and space is evaluated together with the extent of vaporisation and melting (the latter only for metals) for the different candidate armour materials considered for the design (i.e., Be for the primary first wall, Be and CFCs for the limiter, Be, W, and CFCs for the divertor plates) and including for certain cases low-density vapour shielding effects. The critical heat flux, the change of the coolant parameters and the possible severe degradation of the coolant heat removal capability that could result under certain conditions during these transients, for example for the limiter, are also evaluated. Based on the results, the design implications on the heat removal performance and erosion damage of the variuos ITER PFCs are critically discussed and some recommendations are made for the selection of the most adequate protection materials and optimum armour thickness.
Aerosol infection of calves with Histophilus somni.
Jánosi, Katalin; Stipkovits, László; Glávits, Róbert; Molnár, Tamás; Makrai, László; Gyuranecz, Miklós; Varga, János; Fodor, László
2009-09-01
The purpose of this study was to develop and evaluate an aerosol infection method with Histophilus somni that closely resembles the natural way of infection of calves. Another aim was to compare the virulence of two H. somni strains by collecting clinical and postmortem data of experimentally infected and control animals. Seventeen conventionally reared 3-month-old calves were divided into three groups. Two groups of six animals each were exposed to suspensions containing H. somni on three consecutive days using a vaporiser mask. The third group of five animals was used as control. The data of individual clinical examination were recorded daily. All animals were exterminated, and gross pathology of all lungs was evaluated on the 15th day after the first infection. Both H. somni strains caused an increase of rectal temperature, respiratory signs, decrease of weight gain, and severe catarrhal bronchopneumonia in both infected groups. Although some chronic lesions were detected in the lungs of the control animals as well, the histopathological findings in the infected and control groups were different. H. somni was recultured from all lungs in the challenged groups but it could not be reisolated or detected by PCR examination in the control group. This is the first paper on aerosol challenge of calves with H. somni using repeated infection and verified by detailed pathological, bacteriological and histopathological examination. The infection method proved to be successful. There was no difference in the virulence of the two H. somni strains used in the trial.
Malaria: prevention in travellers.
Croft, Ashley M
2007-11-29
Malaria transmission occurs most frequently in environments with humidity over 60% and ambient temperature of 25-30 degrees C. Risks increase with longer visits and depend on activity. Infection can follow a single mosquito bite. Incubation is usually 10-14 days but can be up to 18 months depending on the strain of parasite. We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of non-drug preventive interventions in adult travellers? What are the effects of drug prophylaxis in adult travellers? What are the effects of antimalaria vaccines in travellers? What are the effects of antimalaria interventions in child travellers, pregnant travellers, and in airline pilots? We searched: Medline, Embase, The Cochrane Library and other important databases up to February 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). We found 69 systematic reviews, RCTs, or observational studies that met our inclusion criteria. In this systematic review we present information relating to the effectiveness and safety of the following interventions: acoustic buzzers, aerosol insecticides, amodiaquine, air conditioning and electric fans, atovaquone-proguanil, biological control measures, chloroquine (alone or with proguanil), diethyltoluamide (DEET), doxycycline, full-length and light-coloured clothing, insecticide-treated clothing/nets, mefloquine, mosquito coils and vaporising mats, primaquine, pyrimethamine-dapsone, pyrimethamine-sulfadoxine, smoke, topical (skin-applied) insect repellents, and vaccines.
[Progress in laser neurosurgery].
Majchrzak, H; Kopera, M; Idzik, M
1991-01-01
Nd:YAG lasers with different wavelengths are used in neurosurgery. Their great advantage is the ability of coagulation of blood vessels and delivery through flexible fiber optics . Nd:YAG laser with wavelength 1.318 microns is used, besides, to connect blood vessels and nerves. CO2 laser is the best cutting tool but requires, for delivery rigid cable. Both types of lasers cause shrinkage and vaporisation of the tumors what facilitates its removing without greater traumatisation of surrounding tissues. The introduction of sapphire contact tips to Nd:YAG and argon lasers enables application of small laser powers and diminish the area of damage in surrounding structures. Contact laser is used for destroying of tumours, coagulation of blood vessels, restoration of patency of the main arteries, interstitial denaturation of gliomas and denaturation of the nucleus pulposus in lumbar vertebral column.
Aguiar, Joana; Chebroux, Alexandre; Martinez-Taboada, Fernando; Leece, Elizabeth A
2015-02-01
The aim of this study was to evaluate the analgesic effects of maxillary and/or inferior alveolar nerve blocks with lidocaine and bupivacaine in cats undergoing dental extractions. Twenty-nine cats were enrolled. Using an adapted composite pain scale, cats were pain scored before the dental procedure and 30 mins, and 1, 2 and 4 h after isoflurane disconnection. Cats were sedated with buprenorphine (20 µg/kg), medetomidine (10 µg/kg) and acepromazine (20 µg/kg) intramuscularly. Anaesthesia was induced using alfaxalone (1-2 mg/kg) intravenously and maintained with isoflurane in oxygen. Each cat was randomly assigned to receive maxillary and/or inferior alveolar nerve blocks or no nerve blocks prior to dental extractions. Each nerve block was performed using lidocaine (0.25 mg/kg) and bupivacaine (0.25 mg/kg). Heart rate, systolic arterial blood pressure, respiratory rate, end tidal carbon dioxide and isoflurane vaporiser settings were recorded 5 mins before and after the dental extractions, and the difference calculated. Group mean differences (mean ± SD) for heart rate (-9.7 ± 10.6 vs 7.6 ± 9.5 beats/min [nerve block vs control group, respectively], P <0.0001), systolic arterial blood pressure (-10.33 ± 18.44 vs 5.21 ± 15.23 mmHg, P = 0.02) and vaporiser settings (-0.2 ± 0.2 vs 0.1 ± 0.4, P = 0.023) were significantly different between groups. The control group had higher postoperative pain scores (median [interquartile range]) at 2 h (3 [1.75-4.00] vs 1 [0-2], P = 0.008) and 4 h (4 [2-6] vs 2 [1-2], P = 0.006) after the dental extractions. Maxillary and inferior alveolar nerve blocks with lidocaine and bupivacaine administered prior to dental extractions resulted in a reduction in heart rate and blood pressure while allowing for a reduction in isoflurane. Cats receiving nerve blocks had lower postoperative pain scores than the group without nerve blocks. © ISFM and AAFP 2014.
Assessing the depth of isoflurane anaesthesia during cardiopulmonary bypass.
Ng, Ka Ting; Alston, R Peter; Just, George; McKenzie, Chris
2018-03-01
Bispectral index (BIS) and monitoring of end-tidal concentration may be associated with a reduction in the incidence of awareness during volatile-based general anaesthesia. An analogue of end-tidal concentration during cardiopulmonary bypass (CPB) is measuring exhausted isoflurane concentration from the oxygenator as an estimate to blood and, so, brain concentration. The aim of this study was to determine the relationships between oxygenator exhaust and blood concentrations of isoflurane and the BIS score during CPB when administering isoflurane into the sweep gas supply to the oxygenator. Seventeen patients undergoing elective cardiac surgery using CPB and isoflurane with BIS monitoring were recruited in a single-centre university hospital. Isoflurane gas was delivered via a calibrated vaporiser at the beginning of anaesthetic induction. Radial arterial blood samples were collected after the initiation of CPB and before aortic cross-clamping, which were analysed for isoflurane by gas chromatography and mass spectrometry. The BIS score and the concentration of exhausted isoflurane from the oxygenator membrane, as measured by an anaesthetic gas analyser, were recorded at the time of blood sampling. The mean duration of anaesthetic induction to arterial blood sampling was 90 min (95%CI: 80,100). On CPB, the median BIS was 39 (range, 7-43) and the mean oxygenator exhaust isoflurane concentration was 1.24 ± 0.21%. No significant correlation was demonstrated between BIS with arterial isoflurane concentration (r=-0.19, p=0.47) or oxygenator exhaust isoflurane concentration (r=0.07, p=0.80). Mixed-venous blood temperature was moderately correlated to BIS (r=0.50, p=0.04). Oxygenator exhaust isoflurane concentration was moderately, positively correlated with its arterial concentration (r=0.64, p<0.01). In conclusion, in patients undergoing heart surgery with CPB, the findings of this study indicate that, whilst oxygenator exhaust concentrations were significantly associated with arterial concentrations of isoflurane, neither had any association with the BIS scores, whereas body temperature has moderate positive correlation.
NASA Astrophysics Data System (ADS)
Karnakis, Dimitris; Stephens, Tim; Chabrol, Gregoire
2013-03-01
Rapid developments in organic electronics promise low cost devices for applications such as OLED, organic transistors and organic photovoltaics on large-area glass or flexible substrates in the near future. The technology is very attractive as most device layers can be solution printed. But when directly patterned deposition is impossible, a post-patterning step is required and laser processing is gradually emerging as a key-enabling tool. DPSS lasers offer several advantages including maskless, non-contact, dry patterning, but also scalable large area processing, well suited to roll-to-roll manufacturing at μm resolutions. However, very few reports discuss in detail the merits of DPSS laser patterning technology, especially on flexible substrates. This paper describes the potential of ultrafast DPSS laser technology for OLED fabrication on foil and, specifically, picosecond laser ablation of PEDOT:PSS on multilayered barrier/foil or metal grids aimed as a synthetic alternative to inorganic transparent conductive electrodes. Key requirements include: (a) the complete removal of PEDOT layers without residue, (b) the complete absence of surface contamination from redeposited laser debris to avoid short circuiting and (c) no loss in performance of from laser exposure. We will demonstrate that with careful optimisation and appropriate choice of ultrafast laser, the above criteria can be fulfilled. A suitable process window exists resulting in clean laser structuring without damage to the underlying heat sensitive barrier layers whilst also containing laser debris. A low temperature ablation most likely proceeds via a stress-assisted (film fracture and ejection) process as opposed to vaporisation or other phase change commonly encountered with longer pulse lasers.
Fission product release and microstructure changes of irradiated MOX fuel at high temperatures
NASA Astrophysics Data System (ADS)
Colle, J.-Y.; Hiernaut, J.-P.; Wiss, T.; Beneš, O.; Thiele, H.; Papaioannou, D.; Rondinella, V. V.; Sasahara, A.; Sonoda, T.; Konings, R. J. M.
2013-11-01
Samples of irradiated MOX fuel of 44.5 GWd/tHM mean burn-up were prepared by core drilling at three different radial positions of a fuel pellet. They were subsequently heated in a Knudsen effusion mass spectrometer up to complete vaporisation of the sample (˜2600 K) and the release of fission gas (krypton and xenon) as well as helium was measured. Scanning electron microscopy was used in parallel to investigate the evolution of the microstructure of a sample heated under the same condition up to given key temperatures as determined from the gas release profiles. A clear initial difference for fission gas release and microstructure was observed as a function of the radial position of the samples and therefore of irradiation temperature. A good correlation between the microstructure evolution and the gas release peaks could be established as a function of the temperature of irradiation and (laboratory) heating. The region closest to the cladding (0.58 < r/r0 < 0.96), designated as sample type A in Fig. 1. It represents the "cooler" part of the fuel pellet. The irradiation temperatures (Tirrad) in this range are from 854 to 1312 K (ΔT: 458 K). The intermediate radial zone of the pellet (0.42 < r/r0 < 0.81), designated sample type B in Fig. 1, has a Tirrad ranging from 1068 to 1434 K (ΔT: 365 K). The central zone of the pellet (0.003 < r/r0 < 0.41), designated sample type C in Fig. 1, which was close to the hottest part of the pellet, has a Tirrad ranging from 1442 to 1572 K (ΔT: 131 K). The sample irradiation temperatures were determined from the calculated temperature profile (exponential function) knowing the core temperature of the fuel (1573 K) [11], the standard temperature for this type of fuel at the inner side of the cladding (800 K). The average burnup was calculated with TRANSURANUS code [12] and the PA burnup is the average burnup multiplied by the ratio of the fissile Pu concentration in PA over average fissile Pu concentration in fuel [11]. Calculated burnups correspond reasonably well with measurement of Walker et al. [11]. All those data are shown Fig. 2.Fragments of 2-8 mg were chosen for the experiments. Since these specimens are small compared to the drilled sample size and were taken randomly, the precise radial position could not be determined, in particular the specimens of sample type, A and B could be from close radial locations.Specimens from each drilled sample type were annealed up to complete vaporisation (˜2600 K) at a speed of about 10 K min-1 in a Knudsen effusion mass spectrometer (KEMS) described previously [13,14]. In addition to helium and to the FGs all the species present in the vapour between 83 and 300 a.m.u. were measured during the heating. Additionally, the 85Kr isotope was analysed in a cold trap by β and γ counting. The long-lived fission gas isotopes correspond to masses 131, 132, 134 and 136 for Xe and 83, 84, 85 and 86 for Kr. The absolute quantities of gas released from specimens of sample types A and B were also determined using the in-house built Q-GAMES (Quantitative gas measurement system), described in detail in [15].For each of the samples, fragments were also annealed and measured in the KEMS up to specific temperatures corresponding to different stages of the FGs or He release. These fragments were subsequently analysed by Scanning Electron Microscopy (SEM, Philips XL40) [16] in order to investigate the relationship between structural changes, burn-up, irradiation temperature and fission products release. SEM observations were also done on the samples before the KEMS experiments and the fracture surface appearance of the samples is shown in Fig. 3, revealing the presence of the high burnup structure (HBS) in the Pu-rich agglomerates.A summary of the 12 samples analysed by KEMS, SEM and Q-GAMES is given in Table 1. At 1300 K no clear change potentially related to gas release appears in the UM and PA. At 1450 K a beginning of grain boundaries opening can be observed as well as rounding of the grains attributed to thermal etching. At 1600 K a densification is observed in the PA, smalls grains seem to agglomerate. At 1800 K grain coalescence has occurred in the PA together with formation of large pores. In the UM one observes the formation of a network of intergranular channels. Finally, at 2100 K re-sintering proceeds further and large intra-granular bubbles and five metal precipitates becomes visible. The micrographs of sample type B at 1700 K in Fig. 10, show the formation of small intergranular channel not observed on the image of the sample type A at 1600 K. At 2200 K the intragranular bubbles and intergranular channel are larger than for the sample type A at 2100 K.Images of sample type C (close to pellet centre) are shown in Fig. 11. The PAs did not show the typical HBS-like restructuring but rather loose (open) grains boundaries attributed to the high irradiation temperature. Also big cavities or very large grain boundaries of ˜10 μm were observed (picture 1). The same structure is observed for the UM. After heating at 1700 K, etching and channel formation at the grain boundaries is observed (pictures 3 and 4) similarly as observed for sample types A and B. At 2300 K the fuel was restructured through grain growth and formation of large cavities and intra-granular bubbles (pictures 5 and 6). No fragmentation of the sample has been observed as in very high burnup UO2 fuel [18].
Heat and Mass Transfer with Condensation in Capillary Porous Bodies
2014-01-01
The purpose of this present work is related to wetting process analysis caused by condensation phenomena in capillary porous material by using a numerical simulation. Special emphasis is given to the study of the mechanism involved and the evaluation of classical theoretical models used as a predictive tool. A further discussion will be given for the distribution of the liquid phase for both its pendular and its funicular state and its consequence on diffusion coefficients of the mathematical model used. Beyond the complexity of the interaction effects between vaporisation-condensation processes on the gas-liquid interfaces, the comparison between experimental and numerical simulations permits to identify the specific contribution and the relative part of mass and energy transport parameters. This analysis allows us to understand the contribution of each part of the mathematical model used and to simplify the study. PMID:24688366
Unintended and in situ amorphisation of pharmaceuticals.
Priemel, P A; Grohganz, H; Rades, T
2016-05-01
Amorphisation of poorly water-soluble drugs is one approach that can be applied to improve their solubility and thus their bioavailability. Amorphisation is a process that usually requires deliberate external energy input. However, amorphisation can happen both unintentionally, as in process-induced amorphisation during manufacturing, or in situ during dissolution, vaporisation, or lipolysis. The systems in which unintended and in situ amorphisation has been observed normally contain a drug and a carrier. Common carriers include polymers and mesoporous silica particles. However, the precise mechanisms by which in situ amorphisation occurs are often not fully understood. In situ amorphisation can be exploited and performed before administration of the drug or possibly even within the gastrointestinal tract, as can be inferred from in situ amorphisation observed during in vitro lipolysis. The use of in situ amorphisation can thus confer the advantages of the amorphous form, such as higher apparent solubility and faster dissolution rate, without the disadvantage of its physical instability. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Bulgakov, A. V.; Evtushenko, A. B.; Shukhov, Yu G.; Ozerov, I.; Marin, W.
2010-12-01
Formation of small clusters during pulsed ablation of two binary semiconductors, zinc oxide and indium phosphide, in vacuum by UV, visible, and IR laser radiation is comparatively studied. The irradiation conditions favourable for generation of neutral and charged ZnnOm and InnPm clusters of different stoichiometry in the ablation products are found. The size and composition of the clusters, their expansion dynamics and reactivity are analysed by time-of-flight mass spectrometry. A particular attention is paid to the mechanisms of ZnO and InP ablation as a function of laser fluence, with the use of different ablation models. It is established that ZnO evapourates congruently in a wide range of irradiation conditions, while InP ablation leads to enrichment of the target surface with indium. It is shown that this radically different character of semiconductor ablation determines the composition of the nanostructures formed: zinc oxide clusters are mainly stoichiometric, whereas InnPm particles are significantly enriched with indium.
Martin-Esteban, A; Slowikowski, B; Grobecker, K H
2004-06-17
Solid sampling-electrothermal vaporisation-inductively coupled plasma-mass spectrometry (SS-ETV-ICP-MS) is an attractive technique for the direct simultaneous determination of trace elements in solid samples and especially in long-term studies (i.e. assessment of the homogeneity of reference materials). However, during these studies a downward drift in the instrument sensitivity has been observed due likely to deposits on the sampling and skimmer cones and on the ion lens of the mass spectrometer. Accordingly, in this paper, several means of correcting and/or suppressing sensitivity drift are proposed and evaluated for the monitoring of Cd, Cu, Hg, Mn, Pb, Sb, Se, Sn, Tl, U and V in different reference materials of inorganic and organic (biological) origin. From that studies, the combination of the use of the argon dimer as internal standard together with a modification in the ETV-ICP connection tube seems to be the best mean of getting stable sensitivity during at least 60 consecutive ETV runs.
NASA Astrophysics Data System (ADS)
Mullaney, John C.; Zaleski, Daniel P.; Tew, David Peter; Walker, Nick; Legon, Anthony
2016-06-01
An isolated, gas-phase dimer of imidazole is generated through laser vaporisation of a solid rod containing a 1:1 mixture of imidazole and copper in the presence of an argon buffer gas undergoing supersonic expansion. The complex is characterised through broadband rotational spectroscopy and is shown to have a twisted, hydrogen-bonded geometry. Calculations at the CCSD(T)(F12*)/cc-pVDZ-F12 level of theory confirm this to be the lowest-energy conformer of the imidazole dimer. The distance between the respective centres of mass of the imidazole monomer subunits is determined to be 5.2751(1) Å, and the twist angle γ describing rotation of one monomer with respect to the other about a line connecting the centres of mass of the monomers is determined to be 87.9(4)o. Four out of six intermolecular parameters in the model geometry are precisely determined from the experimental rotational constants and are consistent with results calculated ab initio.
Metastable States Arising from the Ablation of Solid Copper
NASA Astrophysics Data System (ADS)
Andrejeva, Anna; Harris, Joe; Wright, Tim
2014-06-01
Laser ablation is a popular method for generating metal atoms so that metal clusters, complexes, and molecules may be investigated in gas phase spectroscopic studies. However, the initial production of a highly energetic metal plasma from the surface of a solid metal target can produce atoms which are not in their ground electronic state, and consequently atomic spectra can become quite complicated due to transitions arising from metastable atomic excited states which remain populated on the experimental timescale. Presented herein are details of the laser vaporisation source in use by our group. Spectra of atomic copper are presented, recorded via (1+1') and (2+1) resonance enhanced multiphoton ionisation (REMPI) spectroscopy. The energetic regions examined are expected to correspond to the (4s24p) 2P ← 2S and the (4s2nd) 2D ← 2S Rydberg series respectively, but the observed spectra also exhibit many additional contributions which are found to arise from electronically excited states, and these will be discussed.
How two types of fluctuating temperature affect the growth of Fusarium solani
Keith F. Jensen; Phillip E. Reynolds
1969-01-01
Growth of six isolates of Fusarium solani on potato dextrose agar was determined with (1) continually changing temperature programs, (2) programs consisting of two alternating constant temperatures, and (3) a constant temperature program. All programs had a mean of 70º F. Growth increased with an increase in temperature fluctuation of 10 or...
Morel, Aude; Bedek, Gauthier; Salaün, Fabien; Dupont, Daniel
2014-01-01
Protective clothing with high insulation properties helps to keep the wearer safe from flames and other types of hazards. Such protection presents some drawbacks since it hinders movement and decreases comfort, in particular due to heat stress. In fact, sweating causes the accumulation of moisture which directly influences firefighters' performance, decreasing protection due to the increase in radiant heat flux. Vaporisation and condensation of hot moisture also induces skin burn. To evaluate the heat protection of protective clothing, Henrique's equation is used to predict the time leading to second-degree burn. The influence of moisture on protection is complex, i.e., at low radiant heat flux, an increase in moisture content increases protection, and also changes thermal properties. Better understanding of heat and mass transfer in protective clothing is required to develop enhanced protection and to prevent burn injuries. This paper aims to contribute to a better understanding of heat and mass transfer inside firefighters' protective clothing to enhance safety. The focus is on the influence of moisture content and the prevention of steam burn.
A neutron dosemeter for nuclear criticality accidents.
d'Errico, F; Curzio, G; Ciolini, R; Del Gratta, A; Nath, R
2004-01-01
A neutron dosemeter which offers instant read-out has been developed for nuclear criticality accidents. The system is based on gels containing emulsions of superheated dichlorodifluoromethane droplets, which vaporise into bubbles upon neutron irradiation. The expansion of these bubbles displaces an equivalent volume of gel into a graduated pipette, providing an immediate measure of the dose. Instant read-out is achieved using an array of transmissive optical sensors which consist of coupled LED emitters and phototransistor receivers. When the gel displaced in the pipette crosses the sensing region of the photomicrosensors, it generates a signal collected on a computer through a dedicated acquisition board. The performance of the device was tested during the 2002 International Accident Dosimetry Intercomparison in Valduc, France. The dosemeter was able to follow the initial dose gradient of a simulated accident, providing accurate values of neutron kerma; however, the emulsion was rapidly depleted of all its drops. A model of the depletion effects was developed and it indicates that an adequate dynamic range of the dose response can be achieved by using emulsions of smaller droplets.
Poynton, Simon; Sutton, Joseph; Goodall, Sharon; Margham, Jennifer; Forster, Mark; Scott, Ken; Liu, Chuan; McAdam, Kevin; Murphy, James; Proctor, Christopher
2017-08-01
Vapour products have demonstrated potential to be a lower-risk alternative to cigarettes. The present study describes a novel hybrid tobacco product that combines a warm aerosol stream generated by an electronic vaporisation mechanism with tobacco top flavour from cut tobacco. During operation, the aerosol stream released from the vapour cartomiser is passed through a bed of blended cut tobacco by the puffing flow, elevating the tobacco temperature and eluting volatile tobacco flavour components. A preliminary but comprehensive analysis of the aerosol composition of the hybrid tobacco product found that emissions were dominated by the control vapour formulation. In non-targeted chemical screening, no detectable difference in GC scans was observed between the hybrid tobacco product and the control vapour product. However, a sensorially elevated tobacco flavour was confirmed by a consumer sensory panel (P < 0.05). In a targeted analysis of 113 compounds, either identified by regulatory bodies as potential toxicants in cigarette smoke or formed from electronic vapour products, only 26 were quantified. The novel action of tobacco heating and liquid aerosolisation produced classes and levels of toxicants that were similar to those of the control vapour product, but much lower than those of a Kentucky 3R4F reference cigarette. For nine toxicants mandated by the WHO Study Group on Tobacco Product Regulation for reduction in cigarette emissions, the levels were 91%-99% lower per puff in the hybrid tobacco product aerosol than in 3R4F smoke. Overall, the novel hybrid tobacco product provides a sensorially enhanced tobacco flavour, but maintains a toxicant profile similar to its parent vapour product with relatively low levels of known cigarette smoke toxicants. Copyright © 2017 British American Tobacco. Published by Elsevier Ltd.. All rights reserved.
Lipiński, Marek I; Peszyński-Drews, Cezary; Jeromin, Marek Z; Jeromin, Leszek M
2006-01-01
Benign prostatic hyperplasia (BPH) exist in about 70% men after 60 years old. High power KTP laser is a new tool for the treatment of BPH. 49 men were treated by photoselective vaporisation of the prostate (PVP) from August 2003 to May 2004. Thirty patients with follow-up period longer than 12 weeks (12 to 26 weeks) were analyzed. Preoperative prostate volume ranged from 31 to 136 cc. PSA range, estimated before treatment, was normal in all patients (pts). International Prostate Symptom Score (I-PSS) estimated before treatment was over 24 and Quality of Life (QoL) was over 3 in all pts. The maximum peak urinary flow (Qmax) before treatment ranged from 7.2 to 14.1 ml/s. One patient was catheterized with Foley catheter at the finish of the procedure. Two pts required catheterization in the first day after treatment. In two pts increasing of body temperature to 38 degrees C was observed in the first day after treatment. Twenty four hours after treatment haematuria required catheterization was observed in one patient. Seven days after treatment in 4 pts massive haematuria was observed (two required hospitalisation). In one patient because of urinary retention 4 weeks after PVP transurethral resection of the prostate was performed. Four weeks after PVP I-PSS decreased from 24 to 20 and after 12 weeks to 15. The Qmax increased and ranged from 11.3 ml/s to 17.1 ml/s 4 weeks after PVP and 12 weeks after PVP ranged from 15.1 to 22.8 ml/s. Photoselective vaporization of the prostate reduces I-PSS in all patients 12 weeks after procedure. Short follow-up period and a limited number of patients in study group cannot lead to ultimate conclusions. However the results encourage to undertaking further studies on PVP for the treatment of BPH.
NASA Astrophysics Data System (ADS)
Yougoubare, Y. Quentin; Pang, Su-Seng
2014-02-01
In previous work, a biomimetic close-then-heal (CTH) healing mechanism was proposed and validated to repeatedly heal wide-open cracks in load carrying engineering structures by using constrained expansion of compression programmed thermoset shape memory polymers (SMPs). In this study, the effects on healing efficiencies of variation of temperature during both thermomechanical programming and shape recovery (healing) under three-dimensional (3D) confinement are evaluated. The polymer considered is a polystyrene shape memory polymer with 6% by volume of thermoplastic particle additives (copolyester) dispersed in the matrix. In addition to the programming and healing temperatures, some of the parameters investigated include the flexural strength, crack width and elemental composition at the crack interface. It is observed that while increase of the programming temperature is slightly beneficial to strength recovery, most of the strength recovered and damage repair are strongly dependent on the healing temperature. The best healing efficiency (63%) is achieved by a combination of a programming temperature above the glass transition temperature of the polymer and a healing temperature above the bonding point of the copolyester.
Observation of the Central Part of the Beta-Pictoris Disk with an Anti-Blooming CCD
NASA Astrophysics Data System (ADS)
Lecavelier Des Etangs, A.; Perrin, G.; Ferlet, R.; Vidal Madjar, A.; Colas, F.; Buil, C.; Sevre, F.; Arlot, J. E.; Beust, H.; Lagrange Henri, A. M.; Lecacheux, J.; Deleuil, M.; Gry, C.
1993-07-01
β Pictoris (A5V) possesses a circumstellar disk of gas and dust which is oriented edge-on to Earth. Possibly a planet may be indirectly responsible for spectroscopic events, presently interpreted as the signature of the vaporisation of comet-like bodies when grazing the star, and may have cleared up dust particles in the inner zone. Previous coronographic studies coupled with IRAS and ground based IR observations also seem to indicate that the inner regions of the disk may be possibly dust free. We have extended the coronographic studies closer to the star in order to directly observe this zone, through a different observational technique based on the use of an anti- blooming CCD. These new observations, recorded at La Silla (Chile), revealed the structure of the disk down to two arcsec from the star (30 AU from the star). A different nature of dust particles seems to be present in the inner regions of the disk, in possible relation with a planetary formation process. Also an inverted asymmetry is observed in the inner region of the disk when compared to the outer one, a structure possibly related to a non homogeneous distribution of the dust within the disk.
NASA Astrophysics Data System (ADS)
Wallenhorst, L. M.; Loewenthal, L.; Avramidis, G.; Gerhard, C.; Militz, H.; Ohms, G.; Viöl, W.
2017-07-01
In this research, topographic, optical and chemical properties of zinc oxide layers deposited by a cold plasma-spray process were measured. Here, zinc micro particles were fed to the afterglow of a plasma spark discharge whereas the substrates were placed in a quite cold zone of the effluent plasma jet. In this vein, almost closed layers were realised on different samples. As ascertained by laser scanning and atomic force microscopic measurements the particle size of the basic layer is in the nanometre scale. Additionally, larger particles and agglomerates were found on its top. The results indicate a partial plasma-induced diminishment of the initial particles, most probably due to melting or vaporisation. It is further shown that the plasma gives rise to an increased oxidation of such particles as confirmed by X-ray photoelectron spectroscopy. Quantitative analysis of the resulting mixed layer was performed. It is shown that the deposited layers consist of zinc oxide and elemental zinc in approximately equal shares. In addition, the layer's band gap energy was determined by spectroscopic analysis. Here, considerable UV blocking properties of the deposited layers were observed. Possible underlying effects as well as potential applications are presented.
Kofoed, Kristian; Norrbom, Christina; Forslund, Ola; Møller, Charlotte; Frøding, Ligita P; Pedersen, Anders Elm; Markauskas, Algirdas; Blomberg, Maria; Baumgartner-Nielsen, Jane; Madsen, Jakob Torp; Strauss, Gitte; Madsen, Klaus G; Sand, Carsten
2015-02-01
Risk of human papillomavirus (HPV) transmission during laser vaporisation of genital warts or loop electrode excision procedure is controversial. An oral rinse, a nasal swabs, history of HPV related diseases and data on HPV exposure were collected from 287 employees at departments of dermato-venerology and gynaecology in Denmark. A mucosal HPV type was found among 5.8% of employees with experience of laser treatment of genital warts as compared to 1.7% of those with no experience (p = 0.12). HPV prevalence was not higher in employees participating in electrosurgical treatment or cryotherapy of genital warts, or loop electrode excision procedure compared with those who did not. HPV 6 or 11 were not detected in any samples. Hand warts after the age of 24 years was more common among dermatology than among non-dermatology personnel (18% vs. 8.0%, p = 0.03). Mucosal HPV types are infrequent in the oral and nasal cavity of health care personnel, however, employees at departments of dermato-venereology are at risk of acquiring hand warts.
The Electronic Structure of Transition Metal Coated Fullerenes
NASA Astrophysics Data System (ADS)
Patton, David C.; Pederson, Mark R.; Kaxiras, Efthimios
1998-03-01
Clusters composed of fullerene molecules with an outer shell of transition metal atoms in the composition C_60M_62 (M being a transition metal) have been produced with laser vaporisation techniques(F. Tast, N. Malinowski, S. Frank, M. Heinebrodt, I.M.L. Billas, and T. P. Martin, Z. Phys D 40), 351 (1997).. We have studied several of these very large systems with a parallel version of the all-electron NRLMOL cluster code. Optimized geometries of the metal encased fullerenes C_60Ti_62 and C_60V_62 are presented along with their HOMO-LUMO gaps, electron affinities, ionization energies, and cohesive energies. We compare the stability of these clusters to relaxed met-car structures (e.g. Ti_8C_12) and to relaxed rocksalt metal-carbide fragments (TiC)n with n=8 and 32. In addition to metal-coated fullerenes we consider the possibility of a trilayered structure consisting of a small shell of metal atoms enclosed by a metal coated fullerene. The nature of bonding in these systems is analyzed by studying the electronic charge distributions.
Program for an improved hypersonic temperature-sensing probe
NASA Technical Reports Server (NTRS)
Reilly, Richard J.
1993-01-01
Under a NASA Dryden-sponsored contract in the mid 1960s, temperatures of up to 2200 C were successfully measured using a fluid oscillator. The current program, although limited in scope, explores the problem areas which must be solved if this technique is to be extended to 10,000 R. The potential for measuring extremely high temperatures, using fluid oscillator techniques, stems from the fact that the measuring element is the fluid itself. The containing structure of the oscillator need not be brought to equilibrium temperature with with the fluid for temperature measurement, provided that a suitable calibration can be arranged. This program concentrated on review of high-temperature material developments since the original program was completed. Other areas of limited study included related pressure instrumentation requirements, dissociation, rarefied gas effects, and analysis of sensor time response.
[Development of a predictive program for microbial growth under various temperature conditions].
Fujikawa, Hiroshi; Yano, Kazuyoshi; Morozumi, Satoshi; Kimura, Bon; Fujii, Tateo
2006-12-01
A predictive program for microbial growth under various temperature conditions was developed with a mathematical model. The model was a new logistic model recently developed by us. The program predicts Escherichia coli growth in broth, Staphylococcus aureus growth and its enterotoxin production in milk, and Vibrio parahaemolyticus growth in broth at various temperature patterns. The program, which was built with Microsoft Excel (Visual Basic Application), is user-friendly; users can easily input the temperature history of a test food and obtain the prediction instantly on the computer screen. The predicted growth and toxin production can be important indices to determine whether a food is microbiologically safe or not. This program should be a useful tool to confirm the microbial safety of commercial foods.
SPECIFIC HEAT DATA ANALYSIS PROGRAM FOR THE IBM 704 DIGITAL COMPUTER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roach, P.R.
1962-01-01
A computer program was developed to calculate the specific heat of a substance in the temperature range from 0.3 to 4.2 deg K, given temperature calibration data for a carbon resistance thermometer, experimental temperature drift, and heating period data. The speciftc heats calculated from these data are then fitted by a curve by the methods of least squares and the specific heats are corrected for the effect of the curvature of the data. The method, operation, program details, and program stops are discussed. A program listing is included. (M.C.G.)
NASA Astrophysics Data System (ADS)
Kim, Eun Ju; Jeong, Kiyoung; Oh, Seung Jae; Kim, Daehong; Park, Eun Hae; Lee, Young Han; Suh, Jin-Suck
2014-12-01
Magnetic resonance (MR) thermometry is a noninvasive method for monitoring local temperature change during thermal therapy. In this study, a MR temperature analysis program was established for a laser with gold nanorods (GNRs) and high-intensity focused ultrasound (HIFU)-induced heating MR thermometry. The MR temperature map was reconstructed using the water proton resonance frequency (PRF) method. The temperature-sensitive phase difference was acquired by using complex number subtraction instead of direct phase subtraction in order to avoid another phase unwrapping process. A temperature map-analyzing program was developed and implemented in IDL (Interactive Data Language) for effective temperature monitoring. This one program was applied to two different heating devices at a clinical MR scanner. All images were acquired with the fast spoiled gradient echo (fSPGR) pulse sequence on a 3.0 T GE Discovery MR750 scanner with an 8-channel knee array coil or with a home-built small surface coil. The analyzed temperature values were confirmed by using values simultaneously measured with an optical temperature probe (R2 = 0.996). The temperature change in small samples induced by a laser or by HIFU was analyzed by using a raw data, that consisted of complex numbers. This study shows that our MR thermometry analysis program can be used for thermal therapy study with a laser or HIFU at a clinical MR scanner. It can also be applied to temperature monitoring for any other thermal therapy based on the PRF method.
Evaluation of biochars by temperature programmed oxidation/mass spectroscopy
USDA-ARS?s Scientific Manuscript database
Biochar from the thermochemical conversion of biomass was evaluated by Temperature Programmed Oxidation (TPO) coupled with mass spectroscopy. This technique can be used to assess the oxidative reactivity of carbonaceous solids where higher temperature reactivity indicates greater structural order. ...
Zhang, Guozhu; Xie, Changsheng; Zhang, Shunping; Zhao, Jianwei; Lei, Tao; Zeng, Dawen
2014-09-08
A combinatorial high-throughput temperature-programmed method to obtain the optimal operating temperature (OOT) of gas sensor materials is demonstrated here for the first time. A material library consisting of SnO2, ZnO, WO3, and In2O3 sensor films was fabricated by screen printing. Temperature-dependent conductivity curves were obtained by scanning this gas sensor library from 300 to 700 K in different atmospheres (dry air, formaldehyde, carbon monoxide, nitrogen dioxide, toluene and ammonia), giving the OOT of each sensor formulation as a function of the carrier and analyte gases. A comparative study of the temperature-programmed method and a conventional method showed good agreement in measured OOT.
Rapid fabrication of mesoporous TiO2 thin films by pulsed fibre laser for dye sensitized solar cells
NASA Astrophysics Data System (ADS)
Hadi, Aseel; Alhabradi, Mansour; Chen, Qian; Liu, Hong; Guo, Wei; Curioni, Michele; Cernik, Robert; Liu, Zhu
2018-01-01
In this paper we demonstrate for the first time that a fibre laser with a wavelength of 1070 nm and a pulse width of milliseconds can be applied to generate mesoporous nanocrystalline (nc) TiO2 thin films on ITO coated glass in ambient atmosphere, by complete vaporisation of organic binder and inter-connection of TiO2 nanoparticles, without thermally damaging the ITO layer and the glass substrate. The fabrication of the mesoporous TiO2 thin films was achieved by stationary laser beam irradiation of 1 min. The dye sensitized solar cell (DSSC) with the laser-sintered TiO2 photoanode reached higher power conversion efficiency (PCE) of 3.20% for the TiO2 film thickness of 6 μm compared with 2.99% for the furnace-sintered. Electrochemical impedance spectroscopy studies revealed that the laser sintering under the optimised condition effectively decreased charge transfer resistance and increased electron lifetime of the TiO2 thin films. The use of the fibre laser with over 40% wall-plug efficiency offers an economically-feasible, industrial viable solution to the major challenge of rapid fabrication of large scale, mass production of mesoporous metal oxide thin film based solar energy systems, potentially for perovskite and monolithic tandem solar cells, in the future.
Shallow transient liquid water environments on present-day mars, and their implications for life
NASA Astrophysics Data System (ADS)
Jones, Eriita G.
2018-05-01
The identification and characterisation of subsurface liquid water environments on Mars are of high scientific interest. Such environments have the potential to support microbial life, and, more broadly, to develop our understanding of the habitability of planets and moons beyond Earth. Given our current state of knowledge of life on Earth, three pre-requisites are necessary for an environment to be considered 'habitable' and therefore capable of supporting terrestrial-like life: energy, biogenic elements, and liquid water with a sufficiently high water activity. The surface of Mars today is predominately cold and dry, and any liquid water exposed to the atmosphere will vaporise or freeze on timescales of hours to days. These conditions have likely persisted for much of the last 10 million years, and perhaps longer. Despite this, briny liquid water flows (Recurrent Slope Linea) have been observed in a number of locations in the present-day. This review examines evidence from the Phoenix Lander (2008) and the Mars Science Laboratory (2012-current), to assess the occurrence of habitable conditions in the shallow Martian regolith. It will be argued that shallow, transient, liquid water brines are potentially habitable by microbial life, are likely a widespread occurrence on Mars, and that future exploration aimed at finding present-day habitable conditions and potential biology should 'follow the salt'.
NASA's high-temperature engine materials program for civil aeronautics
NASA Technical Reports Server (NTRS)
Gray, Hugh R.; Ginty, Carol A.
1992-01-01
The Advanced High-Temperature Engine Materials Technology Program is described in terms of its research initiatives and its goal of developing propulsion systems for civil aeronautics with low levels of noise, pollution, and fuel consumption. The program emphasizes the analysis and implementation of structural materials such as polymer-matrix composites in fans, casings, and engine-control systems. Also investigated in the program are intermetallic- and metal-matrix composites for uses in compressors and turbine disks as well as ceramic-matrix composites for extremely high-temperature applications such as turbine vanes.
Vanhoenacker, Gerd; Sandra, Pat
2006-08-01
Temperature, as a powerful variable in conventional LC is discussed from a fundamental point of view and illustrated with applications from the author's laboratory. Emphasis is given to the influence of temperature on speed, selectivity, efficiency, detectability, and mobile phase composition (green chromatography). The problems accompanying the use of elevated temperature and temperature programming in LC are reviewed and solutions are described. The available stationary phases for high temperature operation are summarized and a brief overview of recent applications reported in the literature is given.
Evaluation of thermal network correction program using test temperature data
NASA Technical Reports Server (NTRS)
Ishimoto, T.; Fink, L. C.
1972-01-01
An evaluation process to determine the accuracy of a computer program for thermal network correction is discussed. The evaluation is required since factors such as inaccuracies of temperatures, insufficient number of temperature points over a specified time period, lack of one-to-one correlation between temperature sensor and nodal locations, and incomplete temperature measurements are not present in the computer-generated information. The mathematical models used in the evaluation are those that describe a physical system composed of both a conventional and a heat pipe platform. A description of the models used, the results of the evaluation of the thermal network correction, and input instructions for the thermal network correction program are presented.
Delineation of soil temperature regimes from HCMM data
NASA Technical Reports Server (NTRS)
Day, R. L.; Petersen, G. W. (Principal Investigator)
1982-01-01
The subsetting of HCMM data into ORSER format was completed for four dates using a modified SUBSET program. Large areas (approximately 2500 scan lines, 1680 elements) were selected to increase the occurrence of suitable control points for registration. Average daily temperatures (ADT) were calculated for each date. The MERGE program combined registered daytime temperature (DAY-IR) with nighttime temperature (NIGHT-IR) to form a separate two-channel data set. The SUBTRAN program averaged the DAY-IR and NIGHT-IR creating a third ADT channel. Registration equations for the four ADT data sets were generated. A one dimensional soil heat flow equation was modified to allow for mean annual soil temperature predictions using merged ADT data sets.
Evaluation of biochars by temperature programmed oxidation/mass spectrometry
Michael Jackson; Thomas Eberhardt; Akwasi Boateng; Charles Mullen; Les Groom
2013-01-01
Biochars produced from thermochemical conversions of biomass were evaluated by temperature programmed oxidation (TPO). This technique, used to characterize carbon deposits on petroleum cracking catalysts, provides information on the oxidative stability of carbonaceous solids, where higher temperature reactivity indicates greater structural order, an important property...
Diurnal Soil Temperature Effects within the Globe[R] Program Dataset
ERIC Educational Resources Information Center
Witter, Jason D.; Spongberg, Alison L.; Czajkowski, Kevin P.
2007-01-01
Long-term collection of soil temperature with depth is important when studying climate change. The international program GLOBE[R] provides an excellent opportunity to collect such data, although currently endorsed temperature collection protocols need to be refined. To enhance data quality, protocol-based methodology and automated data logging,…
Temperature lowering program for homogeneous doping in flux growth
NASA Astrophysics Data System (ADS)
Qiwei, Wang; Shouquan, Jia
1989-10-01
Based on the mass conservation law and the Burton-Prim-Slichter equation, the temperature program for homogeneous doping in flux growth by slow cooling was derived. The effect of various factors, such as initial supersaturation, solution volume, growth kinetic coefficient and degree of mixing in the solution on growth rate, crystal size and temperature program is discussed in detail. Theoretical analysis shows that there is a critical crystal size above which homogeneous doping is impossible.
NASA Technical Reports Server (NTRS)
Horn, W. J.; Carlson, L. A.
1983-01-01
A FORTRAN computer program called THERMTRAJ is presented which can be used to compute the trajectory of high altitude scientific zero pressure balloons from launch through all subsequent phases of the balloon flight. In addition, balloon gas and film temperatures can be computed at every point of the flight. The program has the ability to account for ballasting, changes in cloud cover, variable atmospheric temperature profiles, and both unconditional valving and scheduled valving of the balloon gas. The program was verified for an extensive range of balloon sizes (from 0.5 to 41.47 million cubic feet). Instructions on program usage, listing of the program source deck, input data and printed and plotted output for a verification case are included.
Mathematical modeling of high and low temperature heat pipes
NASA Technical Reports Server (NTRS)
Chi, S. W.
1971-01-01
Mathematical models are developed for calculating heat-transfer limitations of high-temperature heat pipes and heat-transfer limitations and temperature gradient of low temperature heat pipes. Calculated results are compared with the available experimental data from various sources to increase confidence in the present math models. Complete listings of two computer programs for high- and low-temperature heat pipes respectively are appended. These programs enable the performance of heat pipes with wrapped-screen, rectangular-groove or screen-covered rectangular-groove wick to be predicted.
Assessment of two-temperature kinetic model for dissociating and weakly-ionizing nitrogen
NASA Technical Reports Server (NTRS)
Park, C.
1986-01-01
The validity of the author's two-temperature, chemical/kinetic model which the author has recently improved is assessed by comparing the calculated results with the existing experimental data for nitrogen in the dissociating and weakly ionizing regime produced behind a normal shock wave. The computer program Shock Tube Radiation Program (STRAP) based on the two-temperature model is used in calculating the flow properties behind the shock wave and the Nonequilibrium Air Radiation (NEQAIR) program, in determining the radiative characteristics of the flow. Both programs were developed earlier. Comparison is made between the calculated and the existing shock tube data on (1) spectra in the equilibrium region, (2) rotational temperature of the N2(+) B state, (3) vibrational temperature of the N2(+) B state, (4) electronic excitation temperature of the N2 B state, (5) the shape of time-variation of radiation intensities, (6) the times to reach the peak in radiation intensity and equilibrium, and (7) the ratio of nonequilibrium to equilibrium radiative heat fluxes. Good agreement is seen between the experimental data and the present calculation except for the vibrational temperature. A possible reason for the discrepancy is given.
Stream network and stream segment temperature models software
Bartholow, John
2010-01-01
This set of programs simulates steady-state stream temperatures throughout a dendritic stream network handling multiple time periods per year. The software requires a math co-processor and 384K RAM. Also included is a program (SSTEMP) designed to predict the steady state stream temperature within a single stream segment for a single time period.
Advanced High Temperature Polymer Matrix Composites for Gas Turbine Engines Program Expansion
NASA Technical Reports Server (NTRS)
Hanley, David; Carella, John
1999-01-01
This document, submitted by AlliedSignal Engines (AE), a division of AlliedSignal Aerospace Company, presents the program final report for the Advanced High Temperature Polymer Matrix Composites for Gas Turbine Engines Program Expansion in compliance with data requirements in the statement of work, Contract No. NAS3-97003. This document includes: 1 -Technical Summary: a) Component Design, b) Manufacturing Process Selection, c) Vendor Selection, and d) Testing Validation: 2-Program Conclusion and Perspective. Also, see the Appendix at the back of this report. This report covers the program accomplishments from December 1, 1996, to August 24, 1998. The Advanced High Temperature PMC's for Gas Turbine Engines Program Expansion was a one year long, five task technical effort aimed at designing, fabricating and testing a turbine engine component using NASA's high temperature resin system AMB-21. The fiber material chosen was graphite T650-35, 3K, 8HS with UC-309 sizing. The first four tasks included component design and manufacturing, process selection, vendor selection, component fabrication and validation testing. The final task involved monthly financial and technical reports.
Formation of nanocarbon spheres by thermal treatment of woody char from fast pyrolysis process
Qiangu Yan; Hossein Toghiani; Zhiyong Cai; Jilei Zhang
2014-01-01
Influences of thermal treatment conditions of temperature, reaction cycle and time, and purge gas type on nanocarbon formation over bio-chars from fast pyrolysis and effects of thermal reaction cycle and purge gas type on bio-char surface functional groups were investigated by temperature-programmed desorption (TPD) and temperature programmed reduction methods....
Sub-to super-ambient temperature programmable microfabricated gas chromatography column
Robinson, Alex L.; Anderson, Lawrence F.
2004-03-16
A sub- to super-ambient temperature programmable microfabricated gas chromatography column enables more efficient chemical separation of chemical analytes in a gas mixture by combining a thermoelectric cooler and temperature sensing on the microfabricated column. Sub-ambient temperature programming enables the efficient separation of volatile organic compounds and super-ambient temperature programming enables the elution of less volatile analytes within a reasonable time. The small heat capacity and thermal isolation of the microfabricated column improves the thermal time response and power consumption, both important factors for portable microanalytical systems.
NASA Technical Reports Server (NTRS)
Cassenti, B. N.
1983-01-01
The results of a 10-month research and development program for nonlinear structural modeling with advanced time-temperature constitutive relationships are presented. The implementation of the theory in the MARC nonlinear finite element code is discussed, and instructions for the computational application of the theory are provided.
TAP 1: A Finite Element Program for Steady-State Thermal Analysis of Convectively Cooled Structures
NASA Technical Reports Server (NTRS)
Thornton, E. A.
1976-01-01
The program has a finite element library of six elements: two conduction/convection elements to model heat transfer in a solid, two convection elements to model heat transfer in a fluid, and two integrated conduction/convection elements to represent combined heat transfer in tubular and plate/fin fluid passages. Nonlinear thermal analysis due to temperature dependent thermal parameters is performed using the Newton-Raphson iteration method. Program output includes nodal temperatures and element heat fluxes. Pressure drops in fluid passages may be computed as an option. A companion plotting program for displaying the finite element model and predicted temperature distributions is presented. User instructions and sample problems are presented in appendixes.
NASA Technical Reports Server (NTRS)
Lee, A. Y.
1967-01-01
Computer program calculates the steady state fluid distribution, temperature rise, and pressure drop of a coolant, the material temperature distribution of a heat generating solid, and the heat flux distributions at the fluid-solid interfaces. It performs the necessary iterations automatically within the computer, in one machine run.
Burner liner thermal/structural load modeling: TRANCITS program user's manual
NASA Technical Reports Server (NTRS)
Maffeo, R.
1985-01-01
Transfer Analysis Code to Interface Thermal/Structural Problems (TRANCITS) is discussed. The TRANCITS code satisfies all the objectives for transferring thermal data between heat transfer and structural models of combustor liners and it can be used as a generic thermal translator between heat transfer and stress models of any component, regardless of the geometry. The TRANCITS can accurately and efficiently convert the temperature distributions predicted by the heat transfer programs to those required by the stress codes. It can be used for both linear and nonlinear structural codes and can produce nodal temperatures, elemental centroid temperatures, or elemental Gauss point temperatures. The thermal output of both the MARC and SINDA heat transfer codes can be interfaced directly with TRANCITS, and it will automatically produce stress model codes formatted for NASTRAN and MARC. Any thermal program and structural program can be interfaced by using the neutral input and output forms supported by TRANCITS.
Locatable-Body Temperature Monitoring Based on Semi-Active UHF RFID Tags
Liu, Guangwei; Mao, Luhong; Chen, Liying; Xie, Sheng
2014-01-01
This paper presents the use of radio-frequency identification (RFID) technology for the real-time remote monitoring of body temperature, while an associated program can determine the location of the body carrying the respective sensor. The RFID chip's internal integrated temperature sensor is used for both the human-body temperature detection and as a measurement device, while using radio-frequency communication to broadcast the temperature information. The adopted RFID location technology makes use of reference tags together with a nearest neighbor localization algorithm and a multiple-antenna time-division multiplexing location system. A graphical user interface (GUI) was developed for collecting temperature and location data for the data fusion by using RFID protocols. With a puppy as test object, temperature detection and localization experiments were carried out. The measured results show that the applied method, when using a mercury thermometer for comparison in terms of measuring the temperature of the dog, has a good consistency, with an average temperature error of 0.283 °C. When using the associated program over the area of 12.25 m2, the average location error is of 0.461 m, which verifies the feasibility of the sensor-carrier location by using the proposed program. PMID:24675759
Locatable-body temperature monitoring based on semi-active UHF RFID tags.
Liu, Guangwei; Mao, Luhong; Chen, Liying; Xie, Sheng
2014-03-26
This paper presents the use of radio-frequency identification (RFID) technology for the real-time remote monitoring of body temperature, while an associated program can determine the location of the body carrying the respective sensor. The RFID chip's internal integrated temperature sensor is used for both the human-body temperature detection and as a measurement device, while using radio-frequency communication to broadcast the temperature information. The adopted RFID location technology makes use of reference tags together with a nearest neighbor localization algorithm and a multiple-antenna time-division multiplexing location system. A graphical user interface (GUI) was developed for collecting temperature and location data for the data fusion by using RFID protocols. With a puppy as test object, temperature detection and localization experiments were carried out. The measured results show that the applied method, when using a mercury thermometer for comparison in terms of measuring the temperature of the dog, has a good consistency, with an average temperature error of 0.283 °C. When using the associated program over the area of 12.25 m2, the average location error is of 0.461 m, which verifies the feasibility of the sensor-carrier location by using the proposed program.
A Low-Cost CMOS Programmable Temperature Switch
Li, Yunlong; Wu, Nanjian
2008-01-01
A novel uncalibrated CMOS programmable temperature switch with high temperature accuracy is presented. Its threshold temperature Tth can be programmed by adjusting the ratios of width and length of the transistors. The operating principles of the temperature switch circuit is theoretically explained. A floating gate neural MOS circuit is designed to compensate automatically the threshold temperature Tth variation that results form the process tolerance. The switch circuit is implemented in a standard 0.35 μm CMOS process. The temperature switch can be programmed to perform the switch operation at 16 different threshold temperature Tths from 45—120°C with a 5°C increment. The measurement shows a good consistency in the threshold temperatures. The chip core area is 0.04 mm2 and power consumption is 3.1 μA at 3.3V power supply. The advantages of the temperature switch are low power consumption, the programmable threshold temperature and the controllable hysteresis. PMID:27879871
The vapour of imidazolium-based ionic liquids: a mass spectrometry study.
Deyko, A; Lovelock, K R J; Licence, P; Jones, R G
2011-10-06
Eight common dialkylimidazolium-based ionic liquids have been successfully evaporated in ultra-high vacuum and their vapours analysed by line of sight mass spectrometry using electron ionisation. The ionic liquids investigated were 1-alkyl-3-methylimidazolium bis[(trifluoromethane)sulfonyl]imide, [C(n)C(1)Im][Tf(2)N] (where n = 2, 4, 6, 8), 1-alkyl-3-methylimidazolium tetrafluoroborate, [C(n)C(1)Im][BF(4)] (where n = 4, 8), 1-butyl-3-methylimidazolium octylsulfate, [C(4)C(1)Im][C(8)OSO(3)] and 1-butyl-3-methylimidazolium tetrachloroferrate, [C(4)C(1)Im][FeCl(4)]. All ionic liquids studied here evaporated as neutral ion pairs; no evidence of decomposition products in the vapour phase were observed. Key fragment cations of the ionised vapour of the ionic liquids are identified. The appearance energies, E(app), of the parent cation were measured and used to estimate the ionisation energies, E(i), for the vapour phase neutral ion pairs. Measured ionisation energies ranged from 10.5 eV to 13.0 eV. Using both the identity and E(app) values, the fragmentation pathways for a number of fragment cations are postulated. It will be shown that the enthalpy of vaporisation, Δ(vap)H, can successfully be measured using more than one fragment cation, although caution is required as many fragment cations can also be formed by ionisation of decomposition products.
Overview of NASA battery technology program
NASA Technical Reports Server (NTRS)
Riebling, R. W.
1980-01-01
Highlights of NASA's technology program in batteries for space applications are presented. Program elements include: (1) advanced ambient temperature alkaline secondaries, which are primarily nickel-cadmium cells in batteries; (2) a toroidal nickel cadmium secondaries with multi-kilowatt-hour storage capacity primarily for lower orbital applications; (3) ambient temperature lithium batteries, both primary and secondaries, primarily silver hydrogen and high-capacity nickel hydrogen.
Computer program documentation: Raw-to-processed SINDA program (RTOPHS) user's guide
NASA Technical Reports Server (NTRS)
Damico, S. J.
1980-01-01
Use of the Raw to Processed SINDA(System Improved Numerical Differencing Analyzer) Program, RTOPHS, which provides a means of making the temperature prediction data on binary HSTFLO and HISTRY units generated by SINDA available to engineers in an easy to use format, is discussed. The program accomplishes this by reading the HISTRY unit and according to user input instructions, the desired times and temperature prediction data are extracted and written to a word addressable drum file.
Low Energy X-Ray and Electron Physics and Technology for High-Temperature Plasma Diagnostics
1987-10-01
This program in low-energy x-ray physics and technology has expanded into a major program with the principal objective of supporting research and application programs at the new large x-ray source facilities, particularly the high temperature plasma and synchrotron radiation sources. This program addresses the development of absolute x-ray diagnostics for the fusion energy and x-ray laser research and development. The new laboratory includes five specially designed
Temperature effects on metal-alumina-nitride-oxide-silicon memory operations
NASA Astrophysics Data System (ADS)
Padovani, Andrea; Larcher, Luca; Heh, Dawei; Bersuker, Gennadi; Della Marca, Vincenzo; Pavan, Paolo
2010-05-01
We present a detailed investigation of temperature effects on the operation of TaN/Al2O3/Si3N4/SiO2/Si (TANOS) memory devices. We show that not only retention but also program and erase operations are affected significantly by temperature. Using a large set of experimental data and simulations on a variety of TANOS stacks, we show that the temperature dependence of TANOS program and erase operations can be explained by accounting for that the alumina dielectric constant increases by 20%-25% over a 125 K temperature range.
Mathematical modeling of high and low temperature heat pipes
NASA Technical Reports Server (NTRS)
Chi, S. W.
1971-01-01
Following a review of heat and mass transfer theory relevant to heat pipe performance, math models are developed for calculating heat-transfer limitations of high-temperature heat pipes and heat-transfer limitations and temperature gradient of low temperature heat pipes. Calculated results are compared with the available experimental data from various sources to increase confidence in the present math models. Complete listings of two computer programs for high- and low-temperature heat pipes respectively are included. These programs enable the performance to be predicted of heat pipes with wrapped-screen, rectangular-groove, or screen-covered rectangular-groove wick.
(abstract) Ulysses Solar Wind Ion Temperatures: Radial, Latitudinal, and Dynamical Dependencies
NASA Technical Reports Server (NTRS)
Goldstein, B. E.; Smith, E. J.; Gosling, J. T.; McComas, D. J.; Balogh, A.
1996-01-01
Observations of the Ulysses SWOOPS plasma experiment are used to determine the dependencies of solar wind ion temperatures upon radial distance, speed, and other parameters, and to estimate solar wind heating. Comparisons with three dimensional temperature estimates determined from the ion spectra by a least squares fitting program will be provided (only small samples of data have been reduced with this program).
Middle Atmosphere Program. Handbook for MAP. Volume 13: Ground-based Techniques
NASA Technical Reports Server (NTRS)
Vincent, R. A. (Editor)
1984-01-01
Topics of activities in the middle Atmosphere program covered include: lidar systems of aerosol studies; mesosphere temperature; upper atmosphere temperatures and winds; D region electron densities; nitrogen oxides; atmospheric composition and structure; and optical sounding of ozone.
Contour temperature programmed desorption for monitoring multiple chemical reaction products
NASA Astrophysics Data System (ADS)
Chusuei, C. C.; de la Peña, J. V.; Schreifels, J. A.
1999-09-01
A simple method for obtaining a comprehensive overview of major compounds desorbing from the surface during temperature programmed desorption (TPD) experiments is outlined. Standard commercially available equipment is used to perform the experiment. The method is particularly valuable when high molecular mass compounds are being studied. The acquisition of contour temperature programmed desorption (CTPD) spectra, sampling 50-dalton mass ranges at a time in the thermal desorption experiments, is described and demonstrated for the interaction of benzotriazole adsorbed on a Ni(111) surface. Conventional two-dimensional TPD spectra can be extracted from the CTPD by taking vertical slices of the contour.
HEATPLOT: a temperature distribution plotting program for heating
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elrod, D.C.; Turner, W.D.
1977-07-01
HEATPLOT is a temperature distribution plotting program that may be used with HEATING5, a generalized heat conduction code. HEATPLOT is capable of drawing temperature contours (isotherms), temperature-time profiles, and temperature-distance profiles from the current HEATING5 temperature distribution or from temperature changes relative to the initial temperature distribution. Contour plots may be made for two- or three-dimensional models. Temperature-time profiles and temperature-distance profiles may be made for one-, two-, and three-dimensional models. HEATPLOT is an IBM 360/370 computer code which uses the DISSPLA plotting package. Plots may be created on the CALCOMP pen-and-ink, and CALCOMP cathode ray tube (CRT), or themore » EAI pen-and-ink plotters. Printer plots may be produced or a compressed data set that may be routed to any of the available plotters may be made.« less
NASA Technical Reports Server (NTRS)
Buchele, D. R.
1977-01-01
A computer program to calculate the temperature profile of a flame or hot gas was presented in detail. Emphasis was on profiles found in jet engine or rocket engine exhaust streams containing H2O or CO2 radiating gases. The temperature profile was assumed axisymmetric with an assumed functional form controlled by two variable parameters. The parameters were calculated using measurements of gas radiation at two wavelengths in the infrared. The program also gave some information on the pressure profile. A method of selection of wavelengths was given that is likely to lead to an accurate determination of the parameters. The program is written in FORTRAN IV language and runs in less than 60 seconds on a Univac 1100 computer.
Computer programs for thermodynamic and transport properties of hydrogen (tabcode-II)
NASA Technical Reports Server (NTRS)
Roder, H. M.; Mccarty, R. D.; Hall, W. J.
1972-01-01
The thermodynamic and transport properties of para and equilibrium hydrogen have been programmed into a series of computer routines. Input variables are the pair's pressure-temperature and pressure-enthalpy. The programs cover the range from 1 to 5000 psia with temperatures from the triple point to 6000 R or enthalpies from minus 130 BTU/lb to 25,000 BTU/lb. Output variables are enthalpy or temperature, density, entropy, thermal conductivity, viscosity, at constant volume, the heat capacity ratio, and a heat transfer parameter. Property values on the liquid and vapor boundaries are conveniently obtained through two small routines. The programs achieve high speed by using linear interpolation in a grid of precomputed points which define the surface of the property returned.
Development of a Temperature Sensor for Jet Engine and Space Missions Environments
NASA Technical Reports Server (NTRS)
Patterson, Richard L.; Hammoud, Ahmad; Culley, Dennis E.; Elbuluk, Malik
2008-01-01
Electronic systems in aerospace and in space exploration missions are expected to encounter extreme temperatures and wide thermal swings. To address the needs for extreme temperature electronics, research efforts exist at the NASA Glenn Research Center (GRC) to develop and evaluate electronics for extreme temperature operations, and to establish their reliability under extreme temperature operation and thermal cycling; conditions that are typical of both the aerospace and space environments. These efforts are supported by the NASA Fundamental Aeronautics/Subsonic Fixed Wing Program and by the NASA Electronic Parts and Packaging (NEPP) Program. This work reports on the results obtained on the development of a temperature sensor geared for use in harsh environments.
NASA Astrophysics Data System (ADS)
Wainwright, Carroll L.
2012-09-01
I present a numerical package (CosmoTransitions) for analyzing finite-temperature cosmological phase transitions driven by single or multiple scalar fields. The package analyzes the different vacua of a theory to determine their critical temperatures (where the vacuum energy levels are degenerate), their supercooling temperatures, and the bubble wall profiles which separate the phases and describe their tunneling dynamics. I introduce a new method of path deformation to find the profiles of both thin- and thick-walled bubbles. CosmoTransitions is freely available for public use.Program summaryProgram Title: CosmoTransitionsCatalogue identifier: AEML_v1_0Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEML_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 8775No. of bytes in distributed program, including test data, etc.: 621096Distribution format: tar.gzProgramming language: Python.Computer: Developed on a 2009 MacBook Pro. No computer-specific optimization was performed.Operating system: Designed and tested on Mac OS X 10.6.8. Compatible with any OS with Python installed.RAM: Approximately 50 MB, mostly for loading plotting packages.Classification: 1.9, 11.1.External routines: SciPy, NumPy, matplotLibNature of problem: I describe a program to analyze early-Universe finite-temperature phase transitions with multiple scalar fields. The goal is to analyze the phase structure of an input theory, determine the amount of supercooling at each phase transition, and find the bubble-wall profiles of the nucleated bubbles that drive the transitions.Solution method: To find the bubble-wall profile, the program assumes that tunneling happens along a fixed path in field space. This reduces the equations of motion to one dimension, which can then be solved using the overshoot/undershoot method. The path iteratively deforms in the direction opposite the forces perpendicular to the path until the perpendicular forces vanish (or become very small). To find the phase structure, the program finds and integrates the change in a phase's minimum with respect to temperature.Running time: Approximately 1 minute for full analysis of the two-scalar-field test model on a 2.5 GHz CPU.
Chum, H.L.; Evans, R.J.
1992-08-04
A process is described for using fast pyrolysis in a carrier gas to convert a waste phenolic resin containing feedstreams in a manner such that pyrolysis of said resins and a given high value monomeric constituent occurs prior to pyrolyses of the resins in other monomeric components therein comprising: selecting a first temperature program range to cause pyrolysis of said resin and a given high value monomeric constituent prior to a temperature range that causes pyrolysis of other monomeric components; selecting, if desired, a catalyst and a support and treating said feedstreams with said catalyst to effect acid or basic catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said first temperature program range to utilize reactive gases such as oxygen and steam in the pyrolysis process to drive the production of specific products; differentially heating said feedstreams at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantity of said high value monomeric constituent prior to pyrolysis of other monomeric components therein; separating said high value monomeric constituent; selecting a second higher temperature program range to cause pyrolysis of a different high value monomeric constituent of said phenolic resins waste and differentially heating said feedstreams at said higher temperature program range to cause pyrolysis of said different high value monomeric constituent; and separating said different high value monomeric constituent. 11 figs.
Chum, Helena L.; Evans, Robert J.
1992-01-01
A process of using fast pyrolysis in a carrier gas to convert a waste phenolic resin containing feedstreams in a manner such that pyrolysis of said resins and a given high value monomeric constituent occurs prior to pyrolyses of the resins in other monomeric components therein comprising: selecting a first temperature program range to cause pyrolysis of said resin and a given high value monomeric constituent prior to a temperature range that causes pyrolysis of other monomeric components; selecting, if desired, a catalyst and a support and treating said feedstreams with said catalyst to effect acid or basic catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said first temperature program range to utilize reactive gases such as oxygen and steam in the pyrolysis process to drive the production of specific products; differentially heating said feedstreams at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantity of said high value monomeric constituent prior to pyrolysis of other monomeric components therein; separating said high value monomeric constituent; selecting a second higher temperature program range to cause pyrolysis of a different high value monomeric constituent of said phenolic resins waste and differentially heating said feedstreams at said higher temperature program range to cause pyrolysis of said different high value monomeric constituent; and separating said different high value monomeric constituent.
2010-05-01
23 Task Execution Plan 34 – Temperature Testing of Pyridostigmine Bromide (PB) .......... 23 KEY RESEARCH ACCOMPLISHMENTS...29, 2010. Staff was assembled and materials have been ordered. Task Execution Plan (TEP) 0034 – Temperature Testing of Pyridostigmine Bromide
Evans, R.J.; Chum, H.L.
1998-10-13
A process is described for using fast pyrolysis in a carrier gas to convert a plastic waste feed stream having a mixed polymeric composition in a manner such that pyrolysis of a given polymer to its high value monomeric constituent occurs prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of said given polymer to its high value monomeric constituent prior to a temperature range that causes pyrolysis of other plastic components; selecting a catalyst and support for treating said feed streams with said catalyst to effect acid or base catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said temperature program range; differentially heating said feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituent prior to pyrolysis of other plastic components; separating the high value monomeric constituents; selecting a second higher temperature range to cause pyrolysis of a different high value monomeric constituent of said plastic waste and differentially heating the feed stream at the higher temperature program range to cause pyrolysis of the different high value monomeric constituent; and separating the different high value monomeric constituent. 83 figs.
Evans, Robert J.; Chum, Helena L.
1994-01-01
A process of using fast pyrolysis in a carrier gas to convert a plastic waste feedstream having a mixed polymeric composition in a manner such that pyrolysis of a given polymer to its high value monomeric constituent occurs prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of said given polymer to its high value monomeric constituent prior to a temperature range that causes pyrolysis of other plastic components; selecting a catalyst and support for treating said feed streams with said catalyst to effect acid or base catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said temperature program range; differentially heating said feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituent prior to pyrolysis of other plastic components; separating the high value monomeric constituents, selecting a second higher temperature range to cause pyrolysis of a different high value monomeric constituent of said plastic waste and differentially heating the feedstream at the higher temperature program range to cause pyrolysis of the different high value monomeric constituent; and separating the different high value monomeric constituent.
Evans, Robert J.; Chum, Helena L.
1994-01-01
A process of using fast pyrolysis in a carrier gas to convert a plastic waste feedstream having a mixed polymeric composition in a manner such that pyrolysis of a given polymer to its high value monomeric constituent occurs prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of said given polymer to its high value monomeric constituent prior to a temperature range that causes pyrolysis of other plastic components; selecting a catalyst and support for treating said feed streams with said catalyst to effect acid or base catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said temperature program range; differentially heating said feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituent prior to pyrolysis of other plastic components; separating the high value monomeric constituents; selecting a second higher temperature range to cause pyrolysis of a different high value monomeric constituent of said plastic waste and differentially heating the feedstream at the higher temperature program range to cause pyrolysis of the different high value monomeric constituent; and separating the different high value monomeric constituent.
Evans, Robert J.; Chum, Helena L.
1993-01-01
A process of using fast pyrolysis in a carrier gas to convert a plastic waste feedstream having a mixed polymeric composition in a manner such that pyrolysis of a given polymer to its high value monomeric constituent occurs prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of said given polymer to its high value monomeric constituent prior to a temperature range that causes pyrolysis of other plastic components; selecting a catalyst and support for treating said feed streams with said catalyst to effect acid or base catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said temperature program range; differentially heating said feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituent prior to pyrolysis of other plastic components; separating the high value monomeric constituents; selecting a second higher temperature range to cause pyrolysis of a different high value monomeric constituent of said plastic waste and differentially heating the feedstream at the higher temperature program range to cause pyrolysis of the different high value monomeric constituent; and separating the different high value monomeric constituent.
Evans, Robert J.; Chum, Helena L.
1998-01-01
A process of using fast pyrolysis in a carrier gas to convert a plastic waste feedstream having a mixed polymeric composition in a manner such that pyrolysis of a given polymer to its high value monomeric constituent occurs prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of said given polymer to its high value monomeric constituent prior to a temperature range that causes pyrolysis of other plastic components; selecting a catalyst and support for treating said feed streams with said catalyst to effect acid or base catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said temperature program range; differentially heating said feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituent prior to pyrolysis of other plastic components; separating the high value monomeric constituents; selecting a second higher temperature range to cause pyrolysis of a different high value monomeric constituent of said plastic waste and differentially heating the feedstream at the higher temperature program range to cause pyrolysis of the different high value monomeric constituent; and separating the different high value monomeric constituent.
Temperature and electrical memory of polymer fibers
NASA Astrophysics Data System (ADS)
Yuan, Jinkai; Zakri, Cécile; Grillard, Fabienne; Neri, Wilfrid; Poulin, Philippe
2014-05-01
We report in this work studies of the shape memory behavior of polymer fibers loaded with carbon nanotubes or graphene flakes. These materials exhibit enhanced shape memory properties with the generation of a giant stress upon shape recovery. In addition, they exhibit a surprising temperature memory with a peak of generated stress at a temperature nearly equal to the temperature of programming. This temperature memory is ascribed to the presence of dynamical heterogeneities and to the intrinsic broadness of the glass transition. We present recent experiments related to observables other than mechanical properties. In particular nanocomposite fibers exhibit variations of electrical conductivity with an accurate memory. Indeed, the rate of conductivity variations during temperature changes reaches a well defined maximum at a temperature equal to the temperature of programming. Such materials are promising for future actuators that couple dimensional changes with sensing electronic functionalities.
43 CFR 3261.13 - What is a drilling program and how do I apply for drilling program approval?
Code of Federal Regulations, 2012 CFR
2012-10-01
... the well; (3) If you plan to directionally drill your well, also send us: (i) The proposed bottom hole... reservoir temperature and pressure; (11) Anticipated temperature gradient in the area; (12) A plat certified...
43 CFR 3261.13 - What is a drilling program and how do I apply for drilling program approval?
Code of Federal Regulations, 2011 CFR
2011-10-01
... the well; (3) If you plan to directionally drill your well, also send us: (i) The proposed bottom hole... reservoir temperature and pressure; (11) Anticipated temperature gradient in the area; (12) A plat certified...
43 CFR 3261.13 - What is a drilling program and how do I apply for drilling program approval?
Code of Federal Regulations, 2013 CFR
2013-10-01
... the well; (3) If you plan to directionally drill your well, also send us: (i) The proposed bottom hole... reservoir temperature and pressure; (11) Anticipated temperature gradient in the area; (12) A plat certified...
43 CFR 3261.13 - What is a drilling program and how do I apply for drilling program approval?
Code of Federal Regulations, 2014 CFR
2014-10-01
... the well; (3) If you plan to directionally drill your well, also send us: (i) The proposed bottom hole... reservoir temperature and pressure; (11) Anticipated temperature gradient in the area; (12) A plat certified...
NASA Astrophysics Data System (ADS)
1992-12-01
ESDU 92035 provides details of a FORTRAN program that implements the calculation method of ESDU 83004. It allows performance analysis of an existing design, or the design of a bearing dimensions, subject to any space constraint, are recommended. The predicted performance includes the lubricant film thickness under load, its temperature and flow rate, the power loss, and the bearing temperature. Recommendations are also made on surface finish. Warning messages are output in the following cases, for each of which possible remedial actions are suggested: drain or pad temperature too high, churning losses too great, film thickness too small, pad number too high, ratio or inner to outer pad radius too large, flow rate too great, lubricant or pad temperature outside usable range. A lubricant database is provided that may be extended or edited. The program applies to Newtonian lubricants in laminar flow. Worked examples illustrate the use of the program.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nabeel Riza
In this program, Nuonics, Inc. has studied the fundamentals of a new Silicon Carbide (SiC) materials-based optical sensor technology suited for extreme environments of coal-fired engines in power production. The program explored how SiC could be used for sensing temperature, pressure, and potential gas species in a gas turbine environment. The program successfully demonstrated the optical designs, signal processing and experimental data for enabling both temperature and pressure sensing using SiC materials. The program via its sub-contractors also explored gas species sensing using SiC, in this case, no clear commercially deployable method was proven. Extensive temperature and pressure measurement datamore » using the proposed SiC sensors was acquired to 1000 deg-C and 40 atms, respectively. Importantly, a first time packaged all-SiC probe design was successfully operated in a Siemens industrial turbine rig facility with the probe surviving the harsh chemical, pressure, and temperature environment during 28 days of test operations. The probe also survived a 1600 deg-C thermal shock test using an industrial flame.« less
Peleg, Micha; Normand, Mark D
2015-09-01
When a vitamin's, pigment's or other food component's chemical degradation follows a known fixed order kinetics, and its rate constant's temperature-dependence follows a two parameter model, then, at least theoretically, it is possible to extract these two parameters from two successive experimental concentration ratios determined during the food's non-isothermal storage. This requires numerical solution of two simultaneous equations, themselves the numerical solutions of two differential rate equations, with a program especially developed for the purpose. Once calculated, these parameters can be used to reconstruct the entire degradation curve for the particular temperature history and predict the degradation curves for other temperature histories. The concept and computation method were tested with simulated degradation under rising and/or falling oscillating temperature conditions, employing the exponential model to characterize the rate constant's temperature-dependence. In computer simulations, the method's predictions were robust against minor errors in the two concentration ratios. The program to do the calculations was posted as freeware on the Internet. The temperature profile can be entered as an algebraic expression that can include 'If' statements, or as an imported digitized time-temperature data file, to be converted into an Interpolating Function by the program. The numerical solution of the two simultaneous equations requires close initial guesses of the exponential model's parameters. Programs were devised to obtain these initial values by matching the two experimental concentration ratios with a generated degradation curve whose parameters can be varied manually with sliders on the screen. These programs too were made available as freeware on the Internet and were tested with published data on vitamin A. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Masters, P. A.
1974-01-01
An analysis to predict the pressurant gas requirements for the discharge of cryogenic liquid propellants from storage tanks is presented, along with an algorithm and two computer programs. One program deals with the pressurization (ramp) phase of bringing the propellant tank up to its operating pressure. The method of analysis involves a numerical solution of the temperature and velocity functions for the tank ullage at a discrete set of points in time and space. The input requirements of the program are the initial ullage conditions, the initial temperature and pressure of the pressurant gas, and the time for the expulsion or the ramp. Computations are performed which determine the heat transfer between the ullage gas and the tank wall. Heat transfer to the liquid interface and to the hardware components may be included in the analysis. The program output includes predictions of mass of pressurant required, total energy transfer, and wall and ullage temperatures. The analysis, the algorithm, a complete description of input and output, and the FORTRAN 4 program listings are presented. Sample cases are included to illustrate use of the programs.
Chemical Stockpile Disposal Program. Transportation of Chemical Munitions at Reduced Temperature
1987-08-01
ADA193346 Chemical Stockpile Disposal Program. Transportation of Chemical Munitions at Reduced Temperature. MITRE CORP MCLEAN VA AUG 1987...NO. ACCESSION NO. Aberdeen Proving Ground, fD 21010-5401 11. TITLE (Include Security Classification) Transportation of Chemical Munitions at Reducfd...Year, Month, Day) S. PAGE COUNT nal FROM TO Au USt 1987 65 16. SUPPLEMENTARY NOTATION Prepared for the Chemical Stockpile D’i sal Program Programmatic
Development of a fiber optic high temperature strain sensor
NASA Technical Reports Server (NTRS)
Rausch, E. O.; Murphy, K. E.; Brookshire, S. P.
1992-01-01
From 1 Apr. 1991 to 31 Aug. 1992, the Georgia Tech Research Institute conducted a research program to develop a high temperature fiber optic strain sensor as part of a measurement program for the space shuttle booster rocket motor. The major objectives of this program were divided into four tasks. Under Task 1, the literature on high-temperature fiber optic strain sensors was reviewed. Task 2 addressed the design and fabrication of the strain sensor. Tests and calibration were conducted under Task 3, and Task 4 was to generate recommendations for a follow-on study of a distributed strain sensor. Task 4 was submitted to NASA as a separate proposal.
Summary of laser speckle photogrammetry for HOST
NASA Technical Reports Server (NTRS)
Pollack, Frank G.
1986-01-01
High temperature static strain measurement capability is important for the success of the HOST program. As part of the NASA Lewis effort to develop the technology for improved hot-section durability, the HOST instrumentation program has, as a major goal, the development of methods for measuring strain at high temperature. Development work includes both improvements in resistance strain-gauge technology and, as an alternative approach, the development of optical techniques for high temperature strain measurement.
NASA Technical Reports Server (NTRS)
Matus, Lawrence G.; Seng, Gary T.
1990-01-01
To meet the needs of the aerospace propulsion and space power communities, the high temperature electronics program at the Lewis Research Center is developing silicon carbide (SiC) as a high temperature semiconductor material. This program supports a major element of the Center's mission - to perform basic and developmental research aimed at improving aerospace propulsion systems. Research is focused on developing the crystal growth, characterization, and device fabrication technologies necessary to produce a family of SiC devices.
Combined Loads Test Fixture for Thermal-Structural Testing Aerospace Vehicle Panel Concepts
NASA Technical Reports Server (NTRS)
Fields, Roger A.; Richards, W. Lance; DeAngelis, Michael V.
2004-01-01
A structural test requirement of the National Aero-Space Plane (NASP) program has resulted in the design, fabrication, and implementation of a combined loads test fixture. Principal requirements for the fixture are testing a 4- by 4-ft hat-stiffened panel with combined axial (either tension or compression) and shear load at temperatures ranging from room temperature to 915 F, keeping the test panel stresses caused by the mechanical loads uniform, and thermal stresses caused by non-uniform panel temperatures minimized. The panel represents the side fuselage skin of an experimental aerospace vehicle, and was produced for the NASP program. A comprehensive mechanical loads test program using the new test fixture has been conducted on this panel from room temperature to 500 F. Measured data have been compared with finite-element analyses predictions, verifying that uniform load distributions were achieved by the fixture. The overall correlation of test data with analysis is excellent. The panel stress distributions and temperature distributions are very uniform and fulfill program requirements. This report provides details of an analytical and experimental validation of the combined loads test fixture. Because of its simple design, this unique test fixture can accommodate panels from a variety of aerospace vehicle designs.
Determination of the Arrhenius Activation Energy Using a Temperature-Programmed Flow Reactor.
ERIC Educational Resources Information Center
Chan, Kit-ha C.; Tse, R. S.
1984-01-01
Describes a novel method for the determination of the Arrhenius activation energy, without prejudging the validity of the Arrhenius equation or the concept of activation energy. The method involves use of a temperature-programed flow reactor connected to a concentration detector. (JN)
NECAP 4.1: NASA's Energy-Cost Analysis Program input manual
NASA Technical Reports Server (NTRS)
Jensen, R. N.
1982-01-01
The computer program NECAP (NASA's Energy Cost Analysis Program) is described. The program is a versatile building design and energy analysis tool which has embodied within it state of the art techniques for performing thermal load calculations and energy use predictions. With the program, comparisons of building designs and operational alternatives for new or existing buildings can be made. The major feature of the program is the response factor technique for calculating the heat transfer through the building surfaces which accounts for the building's mass. The program expands the response factor technique into a space response factor to account for internal building temperature swings; this is extremely important in determining true building loads and energy consumption when internal temperatures are allowed to swing.
Automotive Stirling engine development program - Overview and status report
NASA Technical Reports Server (NTRS)
Nightingale, N. P.
1983-01-01
The current status of the automotive-Stirling-engine development program being undertaken by DOE and NASA Lewis is reviewed. The program goals and the reference-engine design are explained, and the modifications introduced to improve performance and lower manufacturing costs are discussed and illustrated, including part-power optimization; increased operating temperature (from 720 to 820 C); 45.4-kg weight reduction; elimination of Co and reduction of Cr used; and improved seals, ceramic components, and high-temperature alloys. The test program, some difficulties encountered, and results after 2042 h are summarized.
NASA Technical Reports Server (NTRS)
Nastrom, G. D.; Jasperson, W. H.
1983-01-01
Temperature data obtained by the Global Atmospheric Sampling Program (GASP) during the period March 1975 to July 1979 are compiled to form flight summaries of static air temperature and a geographic temperature climatology. The flight summaries include the height and location of the coldest observed temperature and the mean flight level, temperature and the standard deviation of temperature for each flight as well as for flight segments. These summaries are ordered by route and month. The temperature climatology was computed for all statistically independent temperture data for each flight. The grid used consists of 5 deg latitude, 30 deg longitude and 2000 feet vertical resolution from FL270 to FL430 for each month of the year. The number of statistically independent observations, their mean, standard deviation and the empirical 98, 50, 16, 2 and .3 probability percentiles are presented.
Low-Temperature Power Electronics Program
NASA Technical Reports Server (NTRS)
Patterson, Richard L.; Dickman, John E.; Hammoud, Ahmad; Gerber, Scott
1997-01-01
Many space and some terrestrial applications would benefit from the availability of low-temperature electronics. Exploration missions to the outer planets, Earth-orbiting and deep-space probes, and communications satellites are examples of space applications which operate in low-temperature environments. Space probes deployed near Pluto must operate in temperatures as low as -229 C. Figure 1 depicts the average temperature of a space probe warmed by the sun for various locations throughout the solar system. Terrestrial applications where components and systems must operate in low-temperature environments include cryogenic instrumentation, superconducting magnetic energy storage, magnetic levitation transportation system, and arctic exploration. The development of electrical power systems capable of extremely low-temperature operation represents a key element of some advanced space power systems. The Low-Temperature Power Electronics Program at NASA Lewis Research Center focuses on the design, fabrication, and characterization of low-temperature power systems and the development of supporting technologies for low-temperature operations such as dielectric and insulating materials, power components, optoelectronic components, and packaging and integration of devices, components, and systems.
NASA Technical Reports Server (NTRS)
Baumeister, Joseph F.; Beach, Duane E.; Armand, Sasan C.
1989-01-01
The proposed Space Station Photovoltaic Deployable Boom was analyzed for operating temperatures. The boom glass/epoxy structure design needs protective shielding from environmental degradation. The protective shielding optical properties (solar absorptivity and emissivity) dictate the operating temperatures of the boom components. The Space Station Boom protective shielding must also withstand the effects of the extendible/retractable coiling acting within the mast canister. A thermal analysis method was developed for the Space Station Deployable Boom to predict transient temperatures for a variety of surface properties. The modeling procedures used to evaluate temperatures within the boom structure incorporated the TRASYS, NEVADA, and SINDA thermal analysis programs. Use of these programs led to a comparison between TRASYS and NEVADA analysis methods. Comparing TRASYS and NEVADA results exposed differences in the environmental solar flux predictions.
NASA Technical Reports Server (NTRS)
Baumeister, Joseph F.; Beach, Duane E.; Armand, Sasan C.
1989-01-01
The proposed Space Station Photovoltaic Deployable Boom was analyzed for operating temperatures. The boom glass/epoxy structure design needs protective shielding from environmental degradation. The protective shielding optical properties (solar absorptivity and emissivity) dictate the operating temperatures of the boom components. The Space Station Boom protective shielding must also withstand the effects of the extendible/retractable coiling action within the mast canister. A thermal analysis method was developed for the Space Station Deployable Boom to predict transient temperatures for a variety of surface properties. The modeling procedures used to evaluate temperatures within the boom structure incorporated the TRASYS, NEVADA, and SINDA thermal analysis programs. Use of these programs led to a comparison between TRASYS and NEVADA analysis methods. Comparing TRASYS and NEVADA results exposed differences in the environmental solar flux predictions.
ERIC Educational Resources Information Center
Kelter, Paul B.; Carr, James D.
1983-01-01
Describes an experiment designed to teach temperature programed gas chromatography (TPGC) techniques and importance of derivatizing many classes of substrated to be separated. Includes equipment needed, procedures for making trimethylsilyl derivatives, applications, sample calculations, and typical results. Procedure required one, three-hour…
NASA Technical Reports Server (NTRS)
Head, D. E.; Mitchell, K. L.
1967-01-01
Program computes the thermal environment of a spacecraft in a lunar orbit. The quantities determined include the incident flux /solar and lunar emitted radiation/, total radiation absorbed by a surface, and the resulting surface temperature as a function of time and orbital position.
United States Air Force Summer Faculty Research Program (1984). Program Management Report. Volume 2.
1984-12-01
temperature properties and thermal stability (2). Perfluorinated fluids which have excellent thermal and oxidative stabilities, have several disadvantages...fluids with improved properties, a Materials Laboratory Program has led to the development of a class of compounds called silahydrocarbons. These... compounds have excellent . . . !.vsct temperature proe operies a ifctdyi thera stbl t empraure xpec e to of 54C o 35°. Snteti hyroarbnsbasd n hdroentedp5y
Program documentation: Surface heating rate of thin skin models (THNSKN)
NASA Technical Reports Server (NTRS)
Mcbryde, J. D.
1975-01-01
Program THNSKN computes the mean heating rate at a maximum of 100 locations on the surface of thin skin transient heating rate models. Output is printed in tabular form and consists of time history tabulation of temperatures, average temperatures, heat loss without conduction correction, mean heating rate, least squares heating rate, and the percent standard error of the least squares heating rates. The input tape used is produced by the program EHTS03.
NASA Technical Reports Server (NTRS)
Gupta, S. K.; Tiwari, S. N.
1976-01-01
A simple procedure and computer program were developed for retrieving the surface temperature from the measurement of upwelling infrared radiance in a single spectral region in the atmosphere. The program evaluates the total upwelling radiance at any altitude in the region of the CO fundamental band (2070-2220 1/cm) for several values of surface temperature. Actual surface temperature is inferred by interpolation of the measured upwelling radiance between the computed values of radiance for the same altitude. Sensitivity calculations were made to determine the effect of uncertainty in various surface, atmospheric and experimental parameters on the inferred value of surface temperature. It is found that the uncertainties in water vapor concentration and surface emittance are the most important factors affecting the accuracy of the inferred value of surface temperature.
Advanced Power Electronics Components
NASA Technical Reports Server (NTRS)
Schwarze, Gene E.
2004-01-01
This paper will give a description and status of the Advanced Power Electronics Materials and Components Technology program being conducted by the NASA Glenn Research Center for future aerospace power applications. The focus of this research program is on the following: 1) New and/or significantly improved dielectric materials for the development of power capacitors with increased volumetric efficiency, energy density, and operating temperature. Materials being investigated include nanocrystalline and composite ceramic dielectrics and diamond-like carbon films; 2) New and/or significantly improved high frequency, high temperature, low loss soft magnetic materials for the development of transformers/inductors with increased power/energy density, electrical efficiency, and operating temperature. Materials being investigated include nanocrystalline and nanocomposite soft magnetic materials; 3) Packaged high temperature, high power density, high voltage, and low loss SiC diodes and switches. Development of high quality 4H- and 6H- SiC atomically smooth substrates to significantly improve device performance is a major emphasis of the SiC materials program; 4) Demonstration of high temperature (> 200 C) circuits using the components developed above.
Evaluation of COTS Electronic Parts for Extreme Temperature Use in NASA Missions
NASA Technical Reports Server (NTRS)
Patterson, Richard L.; Hammoud, Ahmad; Elbuluk, Malik
2008-01-01
Electronic systems capable of extreme temperature operation are required for many future NASA space exploration missions where it is desirable to have smaller, lighter, and less expensive spacecraft and probes. Presently, spacecraft on-board electronics are maintained at about room temperature by use of thermal control systems. An Extreme Temperature Electronics Program at the NASA Glenn Research Center focuses on development of electronics suitable for space exploration missions. The effects of exposure to extreme temperatures and thermal cycling are being investigated for commercial-off-the-shelf components as well as for components specially developed for harsh environments. An overview of this program along with selected data is presented.
Evans, R.J.; Chum, H.L.
1994-10-25
A process of using fast pyrolysis in a carrier gas to convert a plastic waste feedstream having a mixed polymeric composition in a manner such that pyrolysis of a given polymer to its high value monomeric constituent occurs prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of said given polymer to its high value monomeric constituent prior to a temperature range that causes pyrolysis of other plastic components; selecting a catalyst and support for treating said feed streams with said catalyst to effect acid or base catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said temperature program range; differentially heating said feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituent prior to pyrolysis of other plastic components; separating the high value monomeric constituents; selecting a second higher temperature range to cause pyrolysis of a different high value monomeric constituent of said plastic waste and differentially heating the feedstream at the higher temperature program range to cause pyrolysis of the different high value monomeric constituent; and separating the different high value monomeric constituent. 83 figs.
Evans, Robert J.; Chum, Helena L.
1994-01-01
A process of using fast pyrolysis in a carrier gas to convert a plastic waste feedstream having a mixed polymeric composition in a manner such that pyrolysis of a given polymer to its high value monomeric constituent occurs prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of said given polymer to its high value monomeric constituent prior to a temperature range that causes pyrolysis of other plastic components; selecting a catalyst and support for treating said feed streams with said catalyst to effect acid or base catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said temperature program range; differentially heating said feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituent prior to pyrolysis of other plastic components; separating the high value monomeric constituents; selecting a second higher temperature range to cause pyrolysis of a different high value monomeric constituent of said plastic waste and differentially heating the feedstream at the higher temperature program range to cause pyrolysis of the different high value monomeric constituent; and separating the different high value monomeric constituent.
Evans, R.J.; Chum, H.L.
1994-04-05
A process is described for using fast pyrolysis in a carrier gas to convert a plastic waste feedstream having a mixed polymeric composition in a manner such that pyrolysis of a given polymer to its high value monomeric constituent occurs prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of said given polymer to its high value monomeric constituent prior to a temperature range that causes pyrolysis of other plastic components; selecting a catalyst and support for treating said feed streams with said catalyst to effect acid or base catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said temperature program range; differentially heating said feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituent prior to pyrolysis of other plastic components; separating the high value monomeric constituents, selecting a second higher temperature range to cause pyrolysis of a different high value monomeric constituent of said plastic waste and differentially heating the feedstream at the higher temperature program range to cause pyrolysis of the different high value monomeric constituent; and separating the different high value monomeric constituent. 87 figures.
Evans, R.J.; Chum, H.L.
1994-10-25
A process of using fast pyrolysis in a carrier gas to convert a plastic waste feedstream having a mixed polymeric composition in a manner such that pyrolysis of a given polymer to its high value monomeric constituent occurs prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of said given polymer to its high value monomeric constituent prior to a temperature range that causes pyrolysis of other plastic components; selecting a catalyst and support for treating said feed streams with said catalyst to effect acid or base catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said temperature program range; differentially heating said feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituent prior to pyrolysis of other plastic components; separating the high value monomeric constituents; selecting a second higher temperature range to cause pyrolysis of a different high value monomeric constituent of said plastic waste and differentially heating the feedstream at the higher temperature program range to cause pyrolysis of the different high value monomeric constituent; and separating the different high value monomeric constituent. 83 figs.
The Cutting Edge of High-Temperature Composites
NASA Technical Reports Server (NTRS)
2006-01-01
NASA s Ultra-Efficient Engine Technology (UEET) program was formed in 1999 at Glenn Research Center to manage an important national propulsion program for the Space Agency. The UEET program s focus is on developing innovative technologies to enable intelligent, environmentally friendly, and clean-burning turbine engines capable of reducing harmful emissions while maintaining high performance and increasing reliability. Seven technology projects exist under the program, with each project working towards specific goals to provide new technology for propulsion. One of these projects, Materials and Structures for High Performance, is concentrating on developing and demonstrating advanced high-temperature materials to enable high-performance, high-efficiency, and environmentally compatible propulsion systems. Materials include ceramic matrix composite (CMC) combustor liners and turbine vanes, disk alloys, turbine airfoil material systems, high-temperature polymer matrix composites, and lightweight materials for static engine structures.
NASA Technical Reports Server (NTRS)
Hippensteele, S. A.; Colladay, R. S.
1978-01-01
A computer program for determining desired thermodynamic and transport property values by means of a three-dimensional (pressure, fuel-air ratio, and either enthalpy or temperature) interpolation routine was developed. The program calculates temperature (or enthalpy), molecular weight, viscosity, specific heat at constant pressure, thermal conductivity, isentropic exponent (equal to the specific heat ratio at conditions where gases do not react), Prandtl number, and entropy for air and a combustion gas mixture of ASTM-A-1 fuel and air over fuel-air ratios from zero to stoichiometric, pressures from 1 to 40 atm, and temperatures from 250 to 2800 K.
Coutinho, Lincoln Figueira Marins; Nazario, Carlos Eduardo Domingues; Monteiro, Alessandra Maffei; Lanças, Fernando Mauro
2014-08-01
Analyses in chromatographic systems able to save mobile and stationary phases without reducing efficiency and resolution are of current interest. These advantages regarding savings have challenged us to develop a system dedicated to miniaturized liquid chromatography. This paper reports on the development of a high-pressure syringe-type pump, an oven able to perform isothermal and temperature programming and a software program to control these chromatographic devices. The experimental results show that the miniaturized system can generate reproducible and accurate temperature and flow rate. The system was applied to the separation of statins and tetracylines and showed excellent performance. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Kevin P.
2015-02-13
This final technical report details research works performed supported by a Department of Energy grant (DE-FE0003859), which was awarded under the University Coal Research Program administrated by National Energy Technology Laboratory. This research program studied high temperature fiber sensor for harsh environment applications. It developed two fiber optical sensor platform technology including regenerative fiber Bragg grating sensors and distributed fiber optical sensing based on Rayleigh backscattering optical frequency domain reflectometry. Through the studies of chemical and thermal regenerative techniques for fiber Bragg grating (FBG) fabrication, high-temperature stable FBG sensors were successfully developed and fabricated in air-hole microstructured fibers, high-attenuation fibers,more » rare-earth doped fibers, and standard telecommunication fibers. By optimizing the laser processing and thermal annealing procedures, fiber grating sensors with stable performance up to 1100°C have been developed. Using these temperature-stable FBG gratings as sensor platform, fiber optical flow, temperature, pressure, and chemical sensors have been developed to operate at high temperatures up to 800°C. Through the integration of on-fiber functional coating, the use of application-specific air-hole microstructural fiber, and application of active fiber sensing scheme, distributed fiber sensor for temperature, pressure, flow, liquid level, and chemical sensing have been demonstrated with high spatial resolution (1-cm or better) with wide temperature ranges. These include the demonstration of 1) liquid level sensing from 77K to the room temperature, pressure/temperature sensing from the room temperature to 800C and from the 15psi to 2000 psi, and hydrogen concentration measurement from 0.2% to 10% with temperature ranges from the room temperature to 700°C. Optical sensors developed by this program has broken several technical records including flow sensors with the highest operation temperature up to 750°C, first distributed chemical measurements at the record high temperature up to 700°C, first distributed pressure measurement at the record high temperature up to 800°C, and the fiber laser sensors with the record high operation temperature up to 700°C. The research performed by this program dramatically expand the functionality, adaptability, and applicability of distributed fiber optical sensors with potential applications in a number of high-temperature energy systems such as fossil-fuel power generation, high-temperature fuel cell applications, and potential for nuclear energy systems.« less
Computer program to simulate Raman scattering
NASA Technical Reports Server (NTRS)
Zilles, B.; Carter, R.
1977-01-01
A computer program is described for simulating the vibration-rotation and pure rotational spectrum of a combustion system consisting of various diatomic molecules and CO2 as a function of temperature and number density. Two kinds of spectra are generated: a pure rotational spectrum for any mixture of diatomic and linear triatomic molecules, and a vibrational spectrum for diatomic molecules. The program is designed to accept independent rotational and vibrational temperatures for each molecule, as well as number densities.
DOE Office of Scientific and Technical Information (OSTI.GOV)
BRONOWSKI,DAVID R.
The US Department of Energy Offices of Defense Programs and Civilian Radioactive Waste Management jointly sponsored a program to evaluate elastomeric O-ring seal materials for radioactive material shipping containers. The report presents the results of low- and high-temperature tests conducted on 27 common elastomeric compounds.
System for and method of freezing biological tissue
NASA Technical Reports Server (NTRS)
Williams, T. E.; Cygnarowicz, T. A. (Inventor)
1978-01-01
Biological tissue is frozen while a polyethylene bag placed in abutting relationship against opposed walls of a pair of heaters. The bag and tissue are cooled with refrigerating gas at a time programmed rate at least equal to the maximum cooling rate needed at any time during the freezing process. The temperature of the bag, and hence of the tissue, is compared with a time programmed desired value for the tissue temperature to derive an error indication. The heater is activated in response to the error indication so that the temperature of the tissue follows the desired value for the time programmed tissue temperature. The tissue is heated to compensate for excessive cooling of the tissue as a result of the cooling by the refrigerating gas. In response to the error signal, the heater is deactivated while the latent heat of fusion is being removed from the tissue while the tissue is changing phase from liquid to solid.
NASA Technical Reports Server (NTRS)
Cassenti, B. N.
1983-01-01
The results of a 10-month research and development program for the development of advanced time-temperature constitutive relationships are presented. The program included (1) the effect of rate of change of temperature, (2) the development of a term to include time independent effects, and (3) improvements in computational efficiency. It was shown that rate of change of temperature could have a substantial effect on the predicted material response. A modification to include time-independent effects, applicable to many viscoplastic constitutive theories, was shown to reduce to classical plasticity. The computation time can be reduced by a factor of two if self-adaptive integration is used when compared to an integration using ordinary forward differences. During the course of the investigation, it was demonstrated that the most important single factor affecting the theoretical accuracy was the choice of material parameters.
Compliant Foil Journal Bearing Performance at Alternate Pressures and Temperatures
NASA Technical Reports Server (NTRS)
Bruckner, Robert J.; Puleo, Bernadette J.
2008-01-01
An experimental test program has been conducted to determine the highly loaded performance of current generation gas foil bearings at alternate pressures and temperatures. Typically foil bearing performance has been reported at temperatures relevant to turbomachinery applications but only at an ambient pressure of one atmosphere. This dearth of data at alternate pressures has motivated the current test program. Two facilities were used in the test program, the ambient pressure rig and the high pressure rig. The test program utilized a 35 mm diameter by 27 mm long foil journal bearing having an uncoated Inconel X-750 top foil running against a shaft with a PS304 coated journal. Load capacity tests were conducted at 3, 6, 9, 12, 15, 18, and 21 krpm at temperatures from 25 to 500 C and at pressures from 0.1 to 2.5 atmospheres. Results show an increase in load capacity with increased ambient pressure and a reduction in load capacity with increased ambient temperature. Below one-half atmosphere of ambient pressure a dramatic loss of load capacity is experienced. Additional lightly loaded foil bearing performance in nitrogen at 25 C and up to 48 atmospheres of ambient pressure has also been reported. In the lightly loaded region of operation the power loss increases for increasing pressure at a fixed load. Knowledge of foil bearing performance at operating conditions found within potential machine applications will reduce program development risk of future foil bearing supported turbomachines.
SSME structural computer program development. Volume 2: BOPACE users manual
NASA Technical Reports Server (NTRS)
Vos, R. G.
1973-01-01
A computer program for use with a thermal-elastic-plastic-creep structural analyzer is presented. The following functions of the computer program are discussed: (1) analysis of very high temperature and large plastic-creep effects, (2) treatment of cyclic thermal and mechanical loads, (3) development of constitutive theory which closely follows actual behavior under variable temperature conditions, (4) stable numerical solution approach which avoids cumulative errors, and (5) capability of handling up to 1000 degrees of freedom. The computer program is written in FORTRAN IV and has been run on the IBM 360 and UNIVAC 1108 computer systems.
Interfacing of high temperature Z-meter setup using python
NASA Astrophysics Data System (ADS)
Patel, Ashutosh; Sisodia, Shashank; Pandey, Sudhir K.
2017-05-01
In this work, we interface high temperature Z-meter setup to automize the whole measurement process. A program is built on open source programming language `Python' which convert the manual measurement process into fully automated process without any cost addition. Using this program, simultaneous measurement of Seebeck coefficient (α), thermal conductivity (κ) and electrical resistivity (ρ), are performed and using all three, figure-of-merit (ZT) is calculated. Developed program is verified by performing measurement over p-type Bi0.36Sb1.45Te3 sample and the data obtained are found to be in good agreement with the reported data.
Computer program for preliminary design analysis of axial-flow turbines
NASA Technical Reports Server (NTRS)
Glassman, A. J.
1972-01-01
The program method is based on a mean-diameter flow analysis. Input design requirements include power or pressure ratio, flow, temperature, pressure, and speed. Turbine designs are generated for any specified number of stages and for any of three types of velocity diagrams (symmetrical, zero exit swirl, or impulse). Exit turning vanes can be included in the design. Program output includes inlet and exit annulus dimensions, exit temperature and pressure, total and static efficiencies, blading angles, and last-stage critical velocity ratios. The report presents the analysis method, a description of input and output with sample cases, and the program listing.
Toroidal transformer design program with application to inverter circuitry
NASA Technical Reports Server (NTRS)
Dayton, J. A., Jr.
1972-01-01
Estimates of temperature, weight, efficiency, regulation, and final dimensions are included in the output of the computer program for the design of transformers for use in the basic parallel inverter. The program, written in FORTRAN 4, selects a tape wound toroidal magnetic core and, taking temperature, materials, core geometry, skin depth, and ohmic losses into account, chooses the appropriate wire sizes and number of turns for the center tapped primary and single secondary coils. Using the program, 2- and 4-kilovolt-ampere transformers are designed for frequencies from 200 to 3200 Hz and the efficiency of a basic transistor inverter is estimated.
Evans, R.J.; Chum, H.L.
1994-06-14
A process is described using fast pyrolysis to convert a plastic waste feed stream containing polycarbonate and ABS to high value monomeric constituents prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of a given polymer to its high value monomeric constituents prior to a temperature range that causes pyrolysis of other plastic components; selecting an acid or base catalysts and an oxide or carbonate support for treating the feed stream to affect acid or base catalyzed reaction pathways to maximize yield or enhance separation of the high value monomeric constituents of polycarbonate and ABS in the first temperature program range; differentially heating the feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituents prior to pyrolysis or other plastic components; separating the high value monomeric constituents from the polycarbonate to cause pyrolysis to a different high value monomeric constituent of the plastic waste and differentially heating the feed stream at the second higher temperature program range to cause pyrolysis of different high value monomeric constituents; and separating the different high value monomeric constituents. 68 figs.
Evans, Robert J.; Chum, Helena L.
1994-01-01
A process of using fast pyrolysis to convert a plastic waste feed stream containing polycarbonate and ABS to high value monomeric constituents prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of a given polymer to its high value monomeric constituents prior to a temperature range that causes pyrolysis of other plastic components; selecting an acid or base catalysts and an oxide or carbonate support for treating the feed stream to affect acid or base catalyzed reaction pathways to maximize yield or enhance separation of the high value monomeric constituents of polycarbonate and ABS in the first temperature program range; differentially heating the feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituents prior to pyrolysis or other plastic components; separating the high value monomeric constituents from the polycarbonate to cause pyrolysis to a different high value monomeric constituent of the plastic waste and differentially heating the feed stream at the second higher temperature program range to cause pyrolysis of different high value monomeric constituents; and separating the different high value monomeric constituents.
Isotopes in the Arctic atmospheric water cycle
NASA Astrophysics Data System (ADS)
Bonne, Jean-Louis; Werner, Martin; Meyer, Hanno; Kipfstuhl, Sepp; Rabe, Benjamin; Behrens, Melanie; Schönicke, Lutz; Steen Larsen, Hans Christian; Masson-Delmotte, Valérie
2016-04-01
The ISO-ARC project aims at documenting the Arctic atmospheric hydrological cycle, by assessing the imprint of the marine boundary conditions (e.g. temperature variations, circulation changes, or meltwater input) to the isotopic composition of the atmospheric water cycle (H218O and HDO) with a focus on North Atlantic and Arctic oceans. For this purpose, two continuous monitoring water vapour stable isotopes cavity ring-down spectrometers have been installed in July 2015: on-board the Polarstern research vessel and in the Siberian Lena delta Samoylov research station (N 72° 22', E 126° 29'). The Polarstern measurements cover the summer 2015 Arctic campaign from July to mid-October, including six weeks in the Fram Strait region in July- August, followed by a campaign reaching the North Pole and a transect from the Norwegian Sea to the North Sea. These vapour observations are completed by water isotopic measurements in samples from the surface ocean water for Polarstern and from precipitation in Samoylov and Tiksi (120 km south-east of the station). A custom-made designed automatic calibration system has been implemented in a comparable manner for both vapour instruments, based on the injection of different liquid water standards, which are completely vaporised in dry air at high temperature. Subsequent humidity level can be adjusted from 2000 to at least 30000 ppm. For a better resilience, an independent calibration system has been added on the Samoylov instrument, allowing measurements of one standard at humidity levels ranging from 2000 to 15000 ppm: dry air is introduced in a tank containing a large amount of liquid water standard, undergoing evaporation under a controlled environment. The measurement protocol includes an automatic calibration every 25 hours. First instrument characterisation experiments depict a significant isotope-humidity effect at low humidity, dependant on the isotopic composition of the standard. For ambient air, our first isotope measurements highlighted significant synoptic variations in summer in both sites. In Samoylov, the premises of a seasonal cycle have been observed during the summer-fall transition, with a fast humidity level and isotopic decrease. The latitudinal gradient is also highly visible on the Polarstern record. Complementing simulations of the water vapour isotopic composition by the ECHAM5-wiso model reproduce the Polarstern synoptic variability and spatial patterns with a good accuracy. In the near future, our records will be combined with simultaneous water isotope measurements in Iceland (by Hans Christian Steen-Larsen, CIC), Svalbard (by Valérie-Masson Delmotte, LSCE) and paired with complementing climate simulations enhanced by water isotope diagnostics. These data sets, covering an approx. 6,000 km transect of Northern Eurasia will allow for a quantitative assessment of the isotopic variations of the Arctic water cycle. The results of these analyses will also be of relevance for the interpretation of isotope signals found in ice cores and on terrestrial Arctic sites in terms of past climate change.
Multicolor pyrometer for materials processing in space
NASA Technical Reports Server (NTRS)
Frish, M. B.; Frank, J.; Baker, J. E.; Foutter, R. R.; Beerman, H.; Allen, M. G.
1990-01-01
This report documents the work performed by Physical Sciences Inc. (PSI), under contract to NASA JPL, during a 2.5-year SBIR Phase 2 Program. The program goals were to design, construct, and program a prototype passive imaging pyrometer capable of measuring, as accurately as possible, and controlling the temperature distribution across the surface of a moving object suspended in space. These goals were achieved and the instrument was delivered to JPL in November 1989. The pyrometer utilizes an optical system which operates at short wavelengths compared to the peak of the black-body spectrum for the temperature range of interest, thus minimizing errors associated with a lack of knowledge about the heated sample's emissivity. To cover temperatures from 900 to 2500 K, six wavelengths are available. The preferred wavelength for measurement of a particular temperature decreases as the temperature increases. Images at all six wavelengths are projected onto a single CCD camera concurrently. The camera and optical system have been calibrated to relate the measured intensity at each pixel to the temperature of the heated object. The output of the camera is digitized by a frame grabber installed in a personal computer and analyzed automatically to yield temperature information. The data can be used in a feedback loop to alter the status of computer-activated switches and thereby control a heating system.
Aerothermal modeling. Executive summary
NASA Technical Reports Server (NTRS)
Kenworthy, M. K.; Correa, S. M.; Burrus, D. L.
1983-01-01
One of the significant ways in which the performance level of aircraft turbine engines has been improved is by the use of advanced materials and cooling concepts that allow a significant increase in turbine inlet temperature level, with attendant thermodynamic cycle benefits. Further cycle improvements have been achieved with higher pressure ratio compressors. The higher turbine inlet temperatures and compressor pressure ratios with corresponding higher temperature cooling air has created a very hostile environment for the hot section components. To provide the technology needed to reduce the hot section maintenance costs, NASA has initiated the Hot Section Technology (HOST) program. One key element of this overall program is the Aerothermal Modeling Program. The overall objective of his program is to evolve and validate improved analysis methods for use in the design of aircraft turbine engine combustors. The use of such combustor analysis capabilities can be expected to provide significant improvement in the life and durability characteristics of both combustor and turbine components.
NASA Astrophysics Data System (ADS)
Carlo, POGGI; Théo, GUILLAUME; Fabrice, DOVEIL; Laurence, CHÉRIGIER-KOVACIC
2018-07-01
The electric field induced Lyman-α emission diagnostic aims to provide a non intrusive and precise measurement of the electric field in plasma, using a beam of hydrogen atoms prepared in the metastable 2s state. The metastable particles are obtained by means of a proton beam extracted from a hydrogen plasma source, and neutralised by interaction with vaporised caesium. When a 2s atom enters a region where an electric field is present, it undergoes a transition to the 2p state (Stark mixing). It then quickly decays to the ground level, emitting Lyman-α radiation, which is collected by a photomultiplier. The 2s\\to 2p transition rate is proportional to the square of the magnitude of the electric field, and depends on the field oscillation frequency (with peaks around 1 GHz). By measuring the intensity of the Lyman-α radiation emitted by the beam it is possible to determine the magnitude of the field in a defined region. In this work, an analysis of the behaviour of the diagnostic under static or radiofrequency electric field is presented. Electric field simulations obtained with a finite element solver of Maxwell equations, combined with theoretical calculations of the Stark mixing transition rate, are used to develop a model for the interpretation of photomultiplier data. This method shows good agreement with experimental results for the static field case, and allows to measure the field magnitude for the oscillating case.
1989-09-01
and development in Japan onnetallic alloys, ceramics, and composites for use at high temperaturs are described by consid- ering the government programs ...temperatures above about 1,100 0C. carbW PROGRAMS TO DEVELOP IR 3 IMPROVED iIUGH TEUMEAT- 2 ic(C D)BA e fr e d cu sing specific research iiprograms...Performance * Research into conceptual design of Ceramics program is to develop new ceram- ceramics ics with high reliability and toughness when 0
Atmospheric model development in support of SEASAT. Volume 2: Analysis models
NASA Technical Reports Server (NTRS)
Langland, R. A.
1977-01-01
As part of the SEASAT program of NASA, two sets of analysis programs were developed for the Jet Propulsion Laboratory. One set of programs produce 63 x 63 horizontal mesh analyses on a polar stereographic grid. The other set produces 187 x 187 third mesh analyses. The parameters analyzed include sea surface temperature, sea level pressure and twelve levels of upper air temperature, height and wind analyses. The analysis output is used to initialize the primitive equation forecast models.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kasten, P.R.; Rittenhouse, P.L.; Bartine, D.E.
1983-06-01
During 1982 the High-Temperature Gas-Cooled Reactor (HTGR) Technology Program at Oak Ridge National Laboratory (ORNL) continued to develop experimental data required for the design and licensing of cogeneration HTGRs. The program involves fuels and materials development (including metals, graphite, ceramic, and concrete materials), HTGR chemistry studies, structural component development and testing, reactor physics and shielding studies, performance testing of the reactor core support structure, and HTGR application and evaluation studies.
Temperature and solute-transport simulation in streamflow using a Lagrangian reference frame
Jobson, Harvey E.
1980-01-01
A computer program for simulating one-dimensional, unsteady temperature and solute transport in a river has been developed and documented for general use. The solution approach to the convective-diffusion equation uses a moving reference frame (Lagrangian) which greatly simplifies the mathematics of the solution procedure and dramatically reduces errors caused by numerical dispersion. The model documentation is presented as a series of four programs of increasing complexity. The conservative transport model can be used to route a single conservative substance. The simplified temperature model is used to predict water temperature in rivers when only temperature and windspeed data are available. The complete temperature model is highly accurate but requires rather complete meteorological data. Finally, the 10-parameter model can be used to route as many as 10 interacting constituents through a river reach. (USGS)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swindeman, M. J.; Jetter, R. I.; Sham, T. -L.
One of the objectives of the high temperature design methodology activities is to develop and validate both improvements and the basic features of ASME Boiler and Pressure Vessel Code, Section III, Rules for Construction of Nuclear Facility Components, Division 5, High Temperature Reactors, Subsection HB, Subpart B (HBB). The overall scope of this task is to develop a computer program to aid assessment procedures of components under specified loading conditions in accordance with the elevated temperature design requirements for Division 5 Class A components. There are many features and alternative paths of varying complexity in HBB. The initial focus ofmore » this computer program is a basic path through the various options for a single reference material, 316H stainless steel. However, the computer program is being structured for eventual incorporation all of the features and permitted materials of HBB. This report will first provide a description of the overall computer program, particular challenges in developing numerical procedures for the assessment, and an overall approach to computer program development. This is followed by a more comprehensive appendix, which is the draft computer program manual for the program development. The strain limits rules have been implemented in the computer program. The evaluation of creep-fatigue damage will be implemented in future work scope.« less
Elevated temperature crack growth
NASA Technical Reports Server (NTRS)
Kim, K. S.; Vanstone, R. H.
1992-01-01
The purpose of this program was to extend the work performed in the base program (CR 182247) into the regime of time-dependent crack growth under isothermal and thermal mechanical fatigue (TMF) loading, where creep deformation also influences the crack growth behavior. The investigation was performed in a two-year, six-task, combined experimental and analytical program. The path-independent integrals for application to time-dependent crack growth were critically reviewed. The crack growth was simulated using a finite element method. The path-independent integrals were computed from the results of finite-element analyses. The ability of these integrals to correlate experimental crack growth data were evaluated under various loading and temperature conditions. The results indicate that some of these integrals are viable parameters for crack growth prediction at elevated temperatures.
NASA Technical Reports Server (NTRS)
Vanbibber, L. E.; Parker, W. G.
1973-01-01
A computer program was adapted from a previous generation program to analyze the temperature and internal pressure response of a radioactive nuclear waste material disposal container following impact on the earth. This program considers component melting, LiH dissociation, temperature dependent properties and pressure and container stress response. Analyses were performed for 21 cases with variations in radioactive power level, container geometry, degree of deformation of the container, degree of burial and soil properties. Results indicated that the integrity of SS-316 containers could be maintained with partial burials of either underformed or deformed containers. Results indicated that completely buried waste containers, with power levels above 5 kW, experienced creep stress rupture failures in 4 to 12 days.
NASA Technical Reports Server (NTRS)
Taylor, C. M.; Bill, R. C.
1978-01-01
A ceramic/metallic aircraft gas turbine outer gas path seal designed for improved engine performance was studied. Transient temperature and stress profiles in a test seal geometry were determined by numerical analysis. During a simulated engine deceleration cycle from sea-level takeoff to idle conditions, the maximum seal temperature occurred below the seal surface, therefore the top layer of the seal was probably subjected to tensile stresses exceeding the modulus of rupture. In the stress analysis both two- and three-dimensional finite element computer programs were used. Predicted trends of the simpler and more easily usable two-dimensional element programs were borne out by the three-dimensional finite element program results.
Electronics Demonstrated for Low- Temperature Operation
NASA Technical Reports Server (NTRS)
Patterson, Richard L.; Hammond, Ahmad; Gerber, Scott S.
2000-01-01
The operation of electronic systems at cryogenic temperatures is anticipated for many NASA spacecraft, such as planetary explorers and deep space probes. For example, an unheated interplanetary probe launched to explore the rings of Saturn would experience an average temperature near Saturn of about 183 C. Electronics capable of low-temperature operation in the harsh deep space environment also would help improve circuit performance, increase system efficiency, and reduce payload development and launch costs. An ongoing research and development program on low-temperature electronics at the NASA Glenn Research Center at Lewis Field is focusing on the design of efficient power systems that can survive and exploit the advantages of low-temperature environments. The targeted systems, which are mission driven, include converters, inverters, controls, digital circuits, and special-purpose circuits. Initial development efforts successfully demonstrated the low-temperature operation and cold-restart of several direct-current/direct-current (dc/dc) converters based on different types of circuit design, some with superconducting inductors. The table lists some of these dc/dc converters with their properties, and the photograph shows a high-voltage, high-power dc/dc converter designed for an ion propulsion system for low-temperature operation. The development efforts of advanced electronic systems and the supporting technologies for low-temperature operation are being carried out in-house and through collaboration with other Government agencies, industry, and academia. The Low Temperature Electronics Program supports missions and development programs at NASA s Jet Propulsion Laboratory and Goddard Space Flight Center. The developed technologies will be transferred to commercial end users for applications such as satellite infrared sensors and medical diagnostic equipment.
2015-01-01
TEMPERATURES IN HIGH-TEMPERATURE THERMOSETTING POLYMERS 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...illustrated the difficulties inherent in measurement of the glass transition temperature of this high-temperature thermosetting polymer via dynamic...copyright protection in the United States. EFFECT OF IN-SITU CURE ON MEASUREMENT OF GLASS TRANSITION TEMPERATURES IN HIGH-TEMPERATURE THERMOSETTING
ERIC Educational Resources Information Center
Wiederholt, Erwin
1983-01-01
DTA is a technique in which the temperature difference between sample/reference is measured as a function of temperature, while both are subject to a controlled temperature program. Use of a simple DTA-apparatus in demonstrating catalytic effects of manganese dioxide and aluminum oxide on decomposition temperature of potassium chlorate is…
Advanced High Temperature Structural Seals
NASA Technical Reports Server (NTRS)
Newquist, Charles W.; Verzemnieks, Juris; Keller, Peter C.; Shorey, Mark W.; Steinetz, Bruce (Technical Monitor)
2000-01-01
This program addresses the development of high temperature structural seals for control surfaces for a new generation of small reusable launch vehicles. Successful development will contribute significantly to the mission goal of reducing launch cost for small, 200 to 300 lb payloads. Development of high temperature seals is mission enabling. For instance, ineffective control surface seals can result in high temperature (3100 F) flows in the elevon area exceeding structural material limits. Longer sealing life will allow use for many missions before replacement, contributing to the reduction of hardware, operation and launch costs. During the first phase of this program the existing launch vehicle control surface sealing concepts were reviewed, the aerothermal environment for a high temperature seal design was analyzed and a mock up of an arc-jet test fixture for evaluating seal concepts was fabricated.
NASA Technical Reports Server (NTRS)
1991-01-01
Viewgraphs of briefings presented at the SSTAC/ARTS review of the draft Integrated Technology Plan (ITP) on aerothermodynamics, automation and robotics systems, sensors, and high-temperature superconductivity are included. Topics covered include: aerothermodynamics; aerobraking; aeroassist flight experiment; entry technology for probes and penetrators; automation and robotics; artificial intelligence; NASA telerobotics program; planetary rover program; science sensor technology; direct detector; submillimeter sensors; laser sensors; passive microwave sensing; active microwave sensing; sensor electronics; sensor optics; coolers and cryogenics; and high temperature superconductivity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
Viewgraphs of briefings presented at the SSTAC/ARTS review of the draft Integrated Technology Plan (ITP) on aerothermodynamics, automation and robotics systems, sensors, and high-temperature superconductivity are included. Topics covered include: aerothermodynamics; aerobraking; aeroassist flight experiment; entry technology for probes and penetrators; automation and robotics; artificial intelligence; NASA telerobotics program; planetary rover program; science sensor technology; direct detector; submillimeter sensors; laser sensors; passive microwave sensing; active microwave sensing; sensor electronics; sensor optics; coolers and cryogenics; and high temperature superconductivity.
Frost, T.P.; Lindsay, J.R.
1988-01-01
MAGMIX is a BASIC program designed to predict viscosities at thermal equilibrium of interacting magmas of differing compositions, initial temperatures, crystallinities, crystal sizes, and water content for any mixing proportion between end members. From the viscosities of the end members at thermal equilibrium, it is possible to predict the styles of magma interaction expected for different initial conditions. The program is designed for modeling the type of magma interaction between hypersthenenormative magmas at upper crustal conditions. Utilization of the program to model magma interaction at pressures higher than 200 MPa would require modification of the program to account for the effects of pressure on heat of fusion and magma density. ?? 1988.
User's Manual for Thermal Analysis Program of Axially Grooved Heat Pipe (HTGAP)
NASA Technical Reports Server (NTRS)
Kamotani, Y.
1978-01-01
A computer program that numerically predicts the steady state temperature distribution inside an axially grooved heat pipe wall for a given groove geometry and working fluid under various heat input and output modes is described. The program computes both evaporator and condenser film coefficients. The program is able to handle both axisymmetric and nonaxisymmetric heat transfer cases. Non-axisymmetric heat transfer results either from non-uniform input at the evaporator or non-uniform heat removal from the condenser, or from both. The presence of a liquid pool in the condenser region under one-g condition also causes non-axisymmetric heat transfer, and its effect on the pipe wall temperature distribution is included in the present program. The hydrodynamic aspect of an axially grooved heat pipe is studied in the Groove Analysis Program (GAP). The present thermal analysis program assumes that the GAP program (or other similar programs) is run first so that the heat transport limit and optimum fluid charge of the heat pipe are known a priori.
The purpose of this SOP is to assure suitable temperature maintenance in refrigerators and freezers used for sample storage during the Arizona NHEXAS project and the Border study. Keywords: lab; equipment; refrigerators and freezers.
The U.S.-Mexico Border Program is sponsored...
LOX/Hydrocarbon Combustion Instability Investigation
NASA Technical Reports Server (NTRS)
Jensen, R. J.; Dodson, H. C.; Claflin, S. E.
1989-01-01
The LOX/Hydrocarbon Combustion Instability Investigation Program was structured to determine if the use of light hydrocarbon combustion fuels with liquid oxygen (LOX) produces combustion performance and stability behavior similar to the LOX/hydrogen propellant combination. In particular methane was investigated to determine if that fuel can be rated for combustion instability using the same techniques as previously used for LOX/hydrogen. These techniques included fuel temperature ramping and stability bomb tests. The hot fire program probed the combustion behavior of methane from ambient to subambient temperatures. Very interesting results were obtained from this program that have potential importance to future LOX/methane development programs. A very thorough and carefully reasoned documentation of the experimental data obtained is contained. The hot fire test logic and the associated tests are discussed. Subscale performance and stability rating testing was accomplished using 40,000 lb. thrust class hardware. Stability rating tests used both bombs and fuel temperature ramping techniques. The test program was successful in generating data for the evaluation of the methane stability characteristics relative to hydrogen and to anchor stability models. Data correlations, performance analysis, stability analyses, and key stability margin enhancement parameters are discussed.
Simulation and analysis of main steam control system based on heat transfer calculation
NASA Astrophysics Data System (ADS)
Huang, Zhenqun; Li, Ruyan; Feng, Zhongbao; Wang, Songhan; Li, Wenbo; Cheng, Jiwei; Jin, Yingai
2018-05-01
In this paper, after thermal power plant 300MW boiler was studied, mat lab was used to write calculation program about heat transfer process between the main steam and boiler flue gas and amount of water was calculated to ensure the main steam temperature keeping in target temperature. Then heat transfer calculation program was introduced into Simulink simulation platform based on control system multiple models switching and heat transfer calculation. The results show that multiple models switching control system based on heat transfer calculation not only overcome the large inertia of main stream temperature, a large hysteresis characteristic of main stream temperature, but also adapted to the boiler load changing.
Investigation and evaluation of a computer program to minimize three-dimensional flight time tracks
NASA Technical Reports Server (NTRS)
Parke, F. I.
1981-01-01
The program for the DC 8-D3 flight planning was slightly modified for the three dimensional flight planning for DC 10 aircrafts. Several test runs of the modified program over the North Atlantic and North America were made for verifying the program. While geopotential height and temperature were used in a previous program as meteorological data, the modified program uses wind direction and speed and temperature received from the National Weather Service. A scanning program was written to collect required weather information from the raw data received in a packed decimal format. Two sets of weather data, the 12-hour forecast and 24-hour forecast based on 0000 GMT, are used for dynamic processes in testruns. In order to save computing time only the weather data of the North Atlantic and North America is previously stored in a PCF file and then scanned one by one.
Thielmann, Anika; Viehmann, Anja; Weltermann, Birgitta M
2015-07-14
Immunization programs are among the most effective public health strategies worldwide. Adequate vaccine storage is a prerequisite to assure the vaccines' effectiveness and safety. In a questionnaire survey among a random sample of German primary care physicians, we discovered vaccine storage deficits: 16% of physicians had experience with cold chain breaches either as an error or near error, 49 % did not keep a temperature log, and 21 % did not use a separate refrigerator for vaccine storage. In a recent feasibility study of 21 practice refrigerators, we showed that these were outside the target range 10.2% of the total time with some single refrigerators being outside the target range as much as 66.3% of the time. These cooling-chain deficits are consistent with the international medical literature, yet an effective, easy to disseminate, practice-centered intervention to improve storage conditions is lacking. This randomized intervention trial will be conducted in a random sample of primary care practices. Based on continuous temperature recordings over 7 days, all practices with readings outside the target range for vaccine storage (+2 °C to +8 °C) will be randomly allocated to a web-based education program or a waiting list control group. The practice physicians and their teams constitute the target population. Participants will be educated about best practices in vaccine storage and will receive a manual including storage checklists and templates for temperature documentation. In all practices, temperatures of the vaccine refrigerators will be monitored continuously using a data logger with a glycol probe as a surrogate for vaccine vial temperature. The effectiveness of the web-based education program will be determined after 6 months in terms of the proportion of refrigerators with vaccine vial temperatures within the target range (+2 °C to +8 °C) during 7-day temperature logging. Secondary outcome parameters include temperature monitoring, no critically low temperatures (≤ -0.5 °C), compliance with storage recommendations, knowledge of good vaccine storage conditions, and assignment of personnel as vaccine storage manager and backup. Keep Cool will develop and evaluate a web-based education program to improve vaccine storage conditions in primary care and thereby ensure immunization safety and effectiveness. DRKS00006561 (date of registration: 20 February 2015).
Achieving ultra-high temperatures with a resistive emitter array
NASA Astrophysics Data System (ADS)
Danielson, Tom; Franks, Greg; Holmes, Nicholas; LaVeigne, Joe; Matis, Greg; McHugh, Steve; Norton, Dennis; Vengel, Tony; Lannon, John; Goodwin, Scott
2016-05-01
The rapid development of very-large format infrared detector arrays has challenged the IR scene projector community to also develop larger-format infrared emitter arrays to support the testing of systems incorporating these detectors. In addition to larger formats, many scene projector users require much higher simulated temperatures than can be generated with current technology in order to fully evaluate the performance of their systems and associated processing algorithms. Under the Ultra High Temperature (UHT) development program, Santa Barbara Infrared Inc. (SBIR) is developing a new infrared scene projector architecture capable of producing both very large format (>1024 x 1024) resistive emitter arrays and improved emitter pixel technology capable of simulating very high apparent temperatures. During earlier phases of the program, SBIR demonstrated materials with MWIR apparent temperatures in excess of 1400 K. New emitter materials have subsequently been selected to produce pixels that achieve even higher apparent temperatures. Test results from pixels fabricated using the new material set will be presented and discussed. A 'scalable' Read In Integrated Circuit (RIIC) is also being developed under the same UHT program to drive the high temperature pixels. This RIIC will utilize through-silicon via (TSV) and Quilt Packaging (QP) technologies to allow seamless tiling of multiple chips to fabricate very large arrays, and thus overcome the yield limitations inherent in large-scale integrated circuits. Results of design verification testing of the completed RIIC will be presented and discussed.
Computer program for determining the thermodynamic properties of Freon refrigerants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riemer, D.H.; Jacobs, H.R.; Boehm, R.F.
1977-12-01
This program was written to be used as a subroutine. The program determines the thermodynamics of Freon refrigerants. The following refrigerants can be analyzed F-11, F-12, F-13, F-14, F-21, F-22, F-23, F-113, and F-114. The subroutine can evaluate a thermodynamic state for these refrigerants given any of the following pairs of state quantities: pressure and quality, pressure and entropy, pressure and enthalpy, temperature and quality, temperature and specific volume, and temperature and pressure. These six pairs of knowns allow the user to analyze any thermodynamic cycle utilizing a refrigerant as the working fluid. The Downing form of the Martin equationmore » of state was used. This report contains a brief description, flow chart and listing of all subroutines required.« less
Computer program for determining the thermodynamic properties of freon refrigerants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riemer, D.H.; Jacobs, H.R.; Boehm, R.F.
1976-07-01
This program was written to be used as a subroutine. The program determines the thermodynamics of Freon refrigerants. The following refrigerants can be analyzed F-11, F-12, F-13, F-14, F-21, F-22, F-23, F-113, and F-114. The subroutine can evaluate a thermodynamic state for these refrigerants given any of the following pairs of state quantities: pressure and quality, pressure and entropy, pressure and enthalpy, temperature and quality, temperature and specific volume and temperature and pressure. These six pairs of knowns allow the user to analyze any thermodynamic cycle utilizing a refrigerant as the working fluid. The Downing form of the Martin equationmore » of state was used. A brief description, flow chart, and listing of all subroutines required are presented.« less
NASTRAN thermal analyzer: A general purpose finite element heat transfer computer program
NASA Technical Reports Server (NTRS)
Lee, H.; Mason, J. B.
1972-01-01
The program not only can render temperature distributions in solids subjected to various thermal boundary conditions, including effects of diffuse-gray thermal radiation, but is fully compatible in capacity and in the finite-element model representation with that of its structural counterpart in the NASTRAN system. The development history of the finite-element approach for determining temperatures is summarized. The scope of analysis capability, program structure, features, and limitations are given with the objective of providing NASTRAN users with an overall veiw of the NASTRAN thermal analyzer.
NASA Technical Reports Server (NTRS)
Majumdar, Alok; Leclair, Andre; Moore, Ric; Schallhorn, Paul
2011-01-01
GFSSP stands for Generalized Fluid System Simulation Program. It is a general-purpose computer program to compute pressure, temperature and flow distribution in a flow network. GFSSP calculates pressure, temperature, and concentrations at nodes and calculates flow rates through branches. It was primarily developed to analyze Internal Flow Analysis of a Turbopump Transient Flow Analysis of a Propulsion System. GFSSP development started in 1994 with an objective to provide a generalized and easy to use flow analysis tool for thermo-fluid systems.
Three-dimensional vector modeling and restoration of flat finite wave tank radiometric measurements
NASA Technical Reports Server (NTRS)
Truman, W. M.; Balanis, C. A.
1977-01-01
The three-dimensional vector interaction between a microwave radiometer and a wave tank was modeled. Computer programs for predicting the response of the radiometer to the brightness temperature characteristics of the surroundings were developed along with a computer program that can invert (restore) the radiometer measurements. It is shown that the computer programs can be used to simulate the viewing of large bodies of water, and is applicable to radiometer measurements received from satellites monitoring the ocean. The water temperature, salinity, and wind speed can be determined.
NASA Technical Reports Server (NTRS)
Rule, W. K.; Giridharan, V.
1991-01-01
A family of user-friendly, DOS PC based, Microsoft BASIC programs written to provide spacecraft designers with empirical predictions of space debris damage to orbiting spacecraft are described. Spacecraft wall temperatures and condensate formation is also predicted. The spacecraft wall configuration is assumed to consist of multilayered insulation (MLI) placed between a Whipple style bumper and the pressure wall. Impact damage predictions are based on data sets of experimental results obtained from simulating debris impacts on spacecraft using light gas guns on earth. A module of the program facilitates the creation of the database of experimental results that is used by the damage prediction modules to predict damage to the bumper, the MLI, and the pressure wall. A finite difference technique is used to predict temperature distributions in the pressure wall, the MLI, and the bumper. Condensate layer thickness is predicted for the case where the pressure wall temperature drops below the dew point temperature of the spacecraft atmosphere.
Experimental verification of the thermodynamic properties for a jet-A fuel
NASA Technical Reports Server (NTRS)
Graciasalcedo, Carmen M.; Brabbs, Theodore A.; Mcbride, Bonnie J.
1988-01-01
Thermodynamic properties for a Jet-A fuel were determined by Shell Development Company in 1970 under a contract for NASA Lewis Research Center. The polynomial fit necessary to include Jet-A fuel (liquid and gaseous phases) in the library of thermodynamic properties of the NASA Lewis Chemical Equilibrium Program is calculated. To verify the thermodynamic data, the temperatures of mixtures of liquid Jet-A injected into a hot nitrogen stream were experimentally measured and compared to those calculated by the program. Iso-octane, a fuel for which the thermodynamic properties are well known, was used as a standard to calibrate the apparatus. The measured temperatures for the iso-octane/nitrogen mixtures reproduced the calculated temperatures except for a small loss due to the non-adiabatic behavior of the apparatus. The measurements for Jet-A were corrected for this heat loss and showed excellent agreement with the calculated temperatures. These experiments show that this process can be adequately described by the thermodynamic properties fitted for the Chemical Equilibrium Program.
Gray, Elmer W; Wyatt, Roger D; Adler, Peter H; Smink, John; Cox, Julie E; Noblet, Ray
2012-06-01
Black fly suppression programs are conducted across a wide range of environmental conditions, targeting a variety of pest species with diverse life histories. Operational applications of Vectobac 12AS (Bacillus thuringiensis subsp. israelensis) were conducted during times characterized by water temperature and turbidity extremes. Applications were conducted in the Yellow River in central Wisconsin targeting Simulium annulus and S. johannseni when water temperatures were 1-2 degrees C. Applications were conducted in the Green River in western North Carolina targeting the S. jenningsi group after a rain event, when portions of the treatment zone experienced turbidities of 276 nephelometric turbidity units. Excellent larvicidal activity was observed in both programs, with 97% mortality or greater being observed at distances over 5 km downstream of a treatment site. Mortality data for larval black flies in 2 operational suppression programs conducted in 2011 demonstrated a negligible effect of near-freezing water temperatures and exceptionally high turbidity on Bti activity.
NASA Technical Reports Server (NTRS)
Green, Robert D.; Kissock, Barbara I.; Bennett, William R.
2010-01-01
This report documents the results of two system related analyses to support the Exploration Technology Development Program (ETDP) Energy Storage Project. The first study documents a trade study to determine the optimum Li-ion battery cell capacity for the ascent stage battery for the Altair lunar lander being developed under the Constellation Systems program. The battery cell capacity for the Ultra High Energy (UHE) Li-ion battery initially chosen as the target for development was 35 A-hr; this study concludes that a 19.4 A-hr cell capacity would be more optimum from a minimum battery mass perspective. The second study in this report is an assessment of available low temperature Li-ion battery cell performance data to determine whether lowering the operating temperature range of the Li-ion battery, in a rover application, could save overall system mass by eliminating thermal control system mass normally needed to maintain battery temperature within a tighter temperature limit than electronics or other less temperature sensitive components. The preliminary assessment for this second study indicates that the reduction in the thermal control system mass is negated by an increase in battery mass to compensate for the loss in battery capacity due to lower temperature operating conditions.
Synthesis and design of silicide intermetallic materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Petrovic, J.J.; Castro, R.G.; Butt, D.P.
1997-04-01
The overall objective of this program is to develop structural silicide-based materials with optimum combinations of elevated temperature strength/creep resistance, low temperature fracture toughness, and high temperature oxidation and corrosion resistance for applications of importance to the U.S. processing industry. A further objective is to develop silicide-based prototype industrial components. The ultimate aim of the program is to work with industry to transfer the structural silicide materials technology to the private sector in order to promote international competitiveness in the area of advanced high temperature materials and important applications in major energy-intensive U.S. processing industries. The program presently has amore » number of developing industrial connections, including a CRADA with Schuller International Inc. targeted at the area of MoSi{sub 2}-based high temperature materials and components for fiberglass melting and processing applications. The authors are also developing an interaction with the Institute of Gas Technology (IGT) to develop silicides for high temperature radiant gas burner applications, for the glass and other industries. Current experimental emphasis is on the development and characterization of MoSi{sub 2}-Si{sub 3}N{sub 4} and MoSi{sub 2}-SiC composites, the plasma spraying of MoSi{sub 2}-based materials, and the joining of MoSi{sub 2} materials to metals.« less
Airway humidification during high-frequency percussive ventilation.
Allan, Patrick F; Hollingsworth, Michael J; Maniere, Gordon C; Rakofsky, Anthony K; Chung, Kevin K; Naworol, Gregory A; Ward, John A; Perello, Michelle; Morris, Michael J
2009-03-01
We were concerned about the risk of inadequate humidification during high-frequency percussive ventilation (HFPV). We studied 5 humidifiers during HFPV with a lung model, at bias gas flows of 10 L/min, 30 L/min, and 50 L/min, and compared the results to those from a comparator ventilator/humidifier setup and to the minimum temperature (30 degrees C) and humidity (30 mg/L) [corrected] recommended by the American Association for Respiratory Care, at both regular room temperature and a high ambient temperature. Temperature was measured at the humidifier outflow point and at the artificial carina. Humidity was measured at the artificial carina. Of the 7 HFPV/humidifier combinations, 2 (the MR850 at a bias flow of 50 L/min, and the ConchaTherm Hi-Flow with VDR nebulizer) provided a carinal temperature equivalent to the comparator setup at room temperature, whereas one HFPV/humidifier combination (the ConchaTherm Hi-Flow with modified programming, at bias flows of 30 L/min and 50 L/min) provided a higher carinal temperature. At high ambient temperature, all of the setups delivered lower carinal temperature than the comparator setup. Only 2 setups (the ConchaTherm with modified programming at a bias flow of 50 L/min, and the ConchaTherm Hi-Flow with VDR nebulizer) provided carinal humidification equivalent to the comparator setup, without regard to ambient temperature; the other humidifiers were less effective. The ConchaTherm with modified programming, and the ConchaTherm with the VDR nebulizer provided the most consistent humidification. HFPV's distinctive gas-flow mechanism may impair gas heating and humidification, so all humidification systems should be tested with HFPV prior to clinical use.
Temperature Variations in Lubricating Films Induced by Viscous Dissipation
NASA Astrophysics Data System (ADS)
Mozaffari, Farshad; Metcalfe, Ralph
2015-11-01
We have studied temperature distributions of lubricating films. The study has applications in tribology where temperature-reduced viscosity decreases load carrying capacity of bearings, or degrades elastomeric seals. The viscosity- temperature dependency is modeled according to ASTM D341-09. We have modeled the film temperature distribution by our finite element program. The program is made up of three modules: the first one solves the general form of Reynolds equation for the film pressure and velocity gradients. The other two solve the energy equation for the film and its solid boundary temperature distributions. The modules are numerically coupled and iteratively converged to the solutions. We have shown that the temperature distribution in the film is strongly coupled with the thermal response at the boundary. In addition, only thermal diffusion across film thickness is dominant. Moreover, thermal diffusion in the lateral directions, as well as all the convection terms, are negligible. The approximation reduces the energy equation to an ordinary differential equation, which significantly simplifies the modeling of temperature -viscosity effects in thin films. Supported by Kalsi Engineering, Inc.
A dynamic model for plant growth: validation study under changing temperatures
NASA Technical Reports Server (NTRS)
Wann, M.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)
1984-01-01
A dynamic simulation model to describe vegetative growth of plants, for which some functions and parameter values have been estimated previously by optimization search techniques and numerical experimentation based on data from constant temperature experiments, is validated under conditions of changing temperatures. To test the predictive capacity of the model, dry matter accumulation in the leaves, stems, and roots of tobacco plants (Nicotiana tabacum L.) was measured at 2- or 3-day intervals during a 5-week period when temperatures in controlled-environment rooms were programmed for changes at weekly and daily intervals and in ascending or descending sequences within a range of 14 to 34 degrees C. Simulations of dry matter accumulation and distribution were carried out using the programmed changes for experimental temperatures and compared with the measured values. The agreement between measured and predicted values was close and indicates that the temperature-dependent functional forms derived from constant-temperature experiments are adequate for modelling plant growth responses to conditions of changing temperatures with switching intervals as short as 1 day.
Computer program for afterheat temperature distribution for mobile nuclear power plant
NASA Technical Reports Server (NTRS)
Parker, W. G.; Vanbibber, L. E.
1972-01-01
ESATA computer program was developed to analyze thermal safety aspects of post-impacted mobile nuclear power plants. Program is written in FORTRAN 4 and designed for IBM 7094/7044 direct coupled system.
Disinfection of Wastewater by Microwaves.
1980-01-01
used. Thermophilic B. stearothermophilus cells were used to try to determine if the mechanism of destruction was thermal. The microwave oven was set at...curve for E. coli B cells heated in a microwave oven temperature programed for 600 C ...... ............ 8 7. Survivor curve for B. stearothermophilus ...ATCC 12980 cells heated in a microwave oven temperature programed for 600 C. 98. Survivor curve for B. stearothermophilus AICC 12980 ........ 9 9
DOE/JPL advanced thermionic technology program
NASA Technical Reports Server (NTRS)
1979-01-01
Progress made in different tasks of the advanced thermionic technology program is described. The tasks include surface and plasma investigations (surface characterization, spectroscopic plasma experiments, and converter theory); low temperature converter development (tungsten emitter, tungsten oxide collector and tungsten emitter, nickel collector); component hardware development (hot shell development); flame-fired silicon carbide converters; high temperature and advanced converter studies; postoperational diagnostics; and correlation of design interfaces.
High temperature arc-track resistant aerospace insulation
NASA Technical Reports Server (NTRS)
Dorogy, William
1994-01-01
The topics are presented in viewgraph form and include the following: high temperature aerospace insulation; Foster-Miller approach to develop a 300 C rated, arc-track resistant aerospace insulation; advantages and disadvantages of key structural features; summary goals and achievements of the phase 1 program; performance goals for selected materials; materials under evaluation; molecular structures of candidate polymers; candidate polymer properties; film properties; and a detailed program plan.
NASA Technical Reports Server (NTRS)
Hosny, W. M.; Tabakoff, W.
1975-01-01
A two-dimensional finite difference numerical technique is presented to determine the temperature distribution in a solid blade of a radial guide vane. A computer program is written in Fortran IV for IBM 370/165 computer. The computer results obtained from these programs have a similar behavior and trend as those obtained by experimental results.
2015-05-20
TEMPERATURES IN HIGH-TEMPERATURE THERMOSETTING POLYMERS 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...temperature thermosetting polymer via dynamic mechanical analysis alone. These difficulties result from the residual cure of samples heated beyond their...98) Prescribed by ANSI Std. 239.18 Effect of In-Situ Cure on Measurement of Glass Transition Temperatures in High-Temperature Thermosetting
Computer program for design analysis of radial-inflow turbines
NASA Technical Reports Server (NTRS)
Glassman, A. J.
1976-01-01
A computer program written in FORTRAN that may be used for the design analysis of radial-inflow turbines was documented. The following information is included: loss model (estimation of losses), the analysis equations, a description of the input and output data, the FORTRAN program listing and list of variables, and sample cases. The input design requirements include the power, mass flow rate, inlet temperature and pressure, and rotational speed. The program output data includes various diameters, efficiencies, temperatures, pressures, velocities, and flow angles for the appropriate calculation stations. The design variables include the stator-exit angle, rotor radius ratios, and rotor-exit tangential velocity distribution. The losses are determined by an internal loss model.
Waltz Mill testing of 345-kV PPP cable
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burghardt, R.R.
1991-09-01
A 345-kV PPP-insulated cable was subjected to a two-year accelerated life test program at the EPRI Waltz Mill Cable Test Facility. Testing started in November 1985 and was successfully completed in September 1988. The program included conductor temperatures ranging from 85{degrees}C to 105{degrees}C and line-to-line voltages from 362 kV to 474 kV. Cyclic testing was performed during 17 of the 24 months. Dissipation factor measurements were made throughout the program. The measurements indicated no deterioration of the cable or splices as a consequence of the high temperatures and voltages applied to them in this test program. 2 refs., 24 figs.
Waltz Mill testing of 765-kV paper-polypropylene-paper (PPP) cable. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burghardt, R.R.
1992-06-01
A 765-kV PPP-insulated cable was subjected to a 27-month accelerated life test program at the EPRI Waltz Mill Cable Test Facility. Testing started in August 1981 and was successfully completed in January 1985. The program included conductor temperatures ranging from 85{degree}C to 105{degree}C and line-to-line voltages from 800 kV to 1050 kV. Cyclic testing was performed during 20 of the 27 months. Dissipation factor measurements were made throughout the program. The measurements indicated no deterioration of the cable or splices as a consequence of the high temperatures and voltages applied to them in this test program.
Waltz Mill testing of 765-kV paper-polypropylene-paper (PPP) cable
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burghardt, R.R.
1992-06-01
A 765-kV PPP-insulated cable was subjected to a 27-month accelerated life test program at the EPRI Waltz Mill Cable Test Facility. Testing started in August 1981 and was successfully completed in January 1985. The program included conductor temperatures ranging from 85{degree}C to 105{degree}C and line-to-line voltages from 800 kV to 1050 kV. Cyclic testing was performed during 20 of the 27 months. Dissipation factor measurements were made throughout the program. The measurements indicated no deterioration of the cable or splices as a consequence of the high temperatures and voltages applied to them in this test program.
NASA Technical Reports Server (NTRS)
Walker, K. P.
1981-01-01
Results of a 20-month research and development program for nonlinear structural modeling with advanced time-temperature constitutive relationships are reported. The program included: (1) the evaluation of a number of viscoplastic constitutive models in the published literature; (2) incorporation of three of the most appropriate constitutive models into the MARC nonlinear finite element program; (3) calibration of the three constitutive models against experimental data using Hastelloy-X material; and (4) application of the most appropriate constitutive model to a three dimensional finite element analysis of a cylindrical combustor liner louver test specimen to establish the capability of the viscoplastic model to predict component structural response.
Investigation of medium and high temperature phase change materials
NASA Technical Reports Server (NTRS)
Heine, D.; Kraehling, H.
1979-01-01
A detailed description of the programs for acquisition and analysis of the test results is given. Basically it concerns three programs. The TEST program controls the recording of the test data. With the THELLI program it is possible to follow the temperature curve recorded for each individual thermoelement during the test. With the AUSW program the test data can be analyzed, to determine, for example, the melting point and the start of melting. The first results of the service life tests are discussed. From these it is attempted to draw inferences for the subsequent tests. An attempt is made to focus on the determination of the area-related mass loss, the reduction in thickness and the corrosion rate as well as optical and scanning electron microscope evaluation.
Thermal/Pyrolysis Gas Flow Analysis of Carbon Phenolic Material
NASA Technical Reports Server (NTRS)
Clayton, J. Louie
2001-01-01
Provided in this study are predicted in-depth temperature and pyrolysis gas pressure distributions for carbon phenolic materials that are externally heated with a laser source. Governing equations, numerical techniques and comparisons to measured temperature data are also presented. Surface thermochemical conditions were determined using the Aerotherm Chemical Equilibrium (ACE) program. Surface heating simulation used facility calibrated radiative and convective flux levels. Temperatures and pyrolysis gas pressures are predicted using an upgraded form of the SINDA/CMA program that was developed by NASA during the Solid Propulsion Integrity Program (SPIP). Multispecie mass balance, tracking of condensable vapors, high heat rate kinetics, real gas compressibility and reduced mixture viscosity's have been added to the algorithm. In general, surface and in-depth temperature comparisons are very good. Specie partial pressures calculations show that a saturated water-vapor mixture is the main contributor to peak in-depth total pressure. Further, for most of the cases studied, the water-vapor mixture is driven near the critical point and is believed to significantly increase the local heat capacity of the composite material. This phenomenon if not accounted for in analysis models may lead to an over prediction in temperature response in charring regions of the material.
NASA Technical Reports Server (NTRS)
Carey, L. D.; Petersen, W. A.; Deierling, W.; Roeder, W. P.
2009-01-01
A new weather radar is being acquired for use in support of America s space program at Cape Canaveral Air Force Station, NASA Kennedy Space Center, and Patrick AFB on the east coast of central Florida. This new radar replaces the modified WSR-74C at Patrick AFB that has been in use since 1984. The new radar is a Radtec TDR 43-250, which has Doppler and dual polarization capability. A new fixed scan strategy was designed to best support the space program. The fixed scan strategy represents a complex compromise between many competing factors and relies on climatological heights of various temperatures that are important for improved lightning forecasting and evaluation of Lightning Launch Commit Criteria (LCC), which are the weather rules to avoid lightning strikes to in-flight rockets. The 0 C to -20 C layer is vital since most generation of electric charge occurs within it and so it is critical in evaluating Lightning LCC and in forecasting lightning. These are two of the most important duties of 45 WS. While the fixed scan strategy that covers most of the climatological variation of the 0 C to -20 C levels with high resolution ensures that these critical temperatures are well covered most of the time, it also means that on any particular day the radar is spending precious time scanning at angles covering less important heights. The goal of this project is to develop a user-friendly, Interactive Data Language (IDL) computer program that will automatically generate optimized radar scan strategies that adapt to user input of the temperature profile and other important parameters. By using only the required scan angles output by the temperature profile adaptive scan strategy program, faster update times for volume scans and/or collection of more samples per gate for better data quality is possible, while maintaining high resolution at the critical temperature levels. The temperature profile adaptive technique will also take into account earth curvature and refraction when geo-locating the radar beam (i.e., beam height and arc distance), including non-standard refraction based on the user-input temperature profile. In addition to temperature profile adaptivity, this paper will also summarize the other requirements for this scan strategy program such as detection of low-level boundaries, detection of anvil clouds, reducing the Cone Of Silence, and allowing for times when deep convective clouds will not occur. The adaptive technique will be carefully compared to and benchmarked against the new fixed scan strategy. Specific environmental scenarios in which the adaptive scan strategy is able to optimize and improve coverage and resolution at critical heights, scan time, and/or sample numbers relative to the fixed scan strategy will be presented.
NASA Technical Reports Server (NTRS)
Kemp, N. H.; Krech, R. H.
1980-01-01
The development of computer codes for the thrust chamber of a rocket of which the propellant gas is heated by a CW laser beam was investigated. The following results are presented: (1) simplified models of laser heated thrusters for approximate parametric studies and performance mapping; (3) computer programs for thrust chamber design; and (3) shock tube experiment to measure absorption coefficients. Two thrust chamber design programs are outlined: (1) for seeded hydrogen, with both low temperature and high temperature seeds, which absorbs the laser radiation continuously, starting at the inlet gas temperature; and (2) for hydrogen seeded with cesium, in which a laser supported combustion wave stands near the gas inlet, and heats the gas up to a temperature at which the gas can absorb the laser energy.
NASA Technical Reports Server (NTRS)
Field, Richard T.
1990-01-01
SOILSIM, a digital model of energy and moisture fluxes in the soil and above the soil surface, is presented. It simulates the time evolution of soil temperature and moisture, temperature of the soil surface and plant canopy the above surface, and the fluxes of sensible and latent heat into the atmosphere in response to surface weather conditions. The model is driven by simple weather observations including wind speed, air temperature, air humidity, and incident radiation. The model intended to be useful in conjunction with remotely sensed information of the land surface state, such as surface brightness temperature and soil moisture, for computing wide area evapotranspiration.
A Temperature Sensor using a Silicon-on-Insulator (SOI) Timer for Very Wide Temperature Measurement
NASA Technical Reports Server (NTRS)
Patterson, Richard L.; Hammoud, Ahmad; Elbuluk, Malik; Culley, Dennis E.
2008-01-01
A temperature sensor based on a commercial-off-the-shelf (COTS) Silicon-on-Insulator (SOI) Timer was designed for extreme temperature applications. The sensor can operate under a wide temperature range from hot jet engine compartments to cryogenic space exploration missions. For example, in Jet Engine Distributed Control Architecture, the sensor must be able to operate at temperatures exceeding 150 C. For space missions, extremely low cryogenic temperatures need to be measured. The output of the sensor, which consisted of a stream of digitized pulses whose period was proportional to the sensed temperature, can be interfaced with a controller or a computer. The data acquisition system would then give a direct readout of the temperature through the use of a look-up table, a built-in algorithm, or a mathematical model. Because of the wide range of temperature measurement and because the sensor is made of carefully selected COTS parts, this work is directly applicable to the NASA Fundamental Aeronautics/Subsonic Fixed Wing Program--Jet Engine Distributed Engine Control Task and to the NASA Electronic Parts and Packaging (NEPP) Program. In the past, a temperature sensor was designed and built using an SOI operational amplifier, and a report was issued. This work used an SOI 555 timer as its core and is completely new work.
Thomas, Ellen M; Chapman, Benjamin; Jaykus, Lee-Ann; Phister, Trevor
2014-09-01
Contaminated fresh produce has been increasingly identified as a cause of foodborne illnesses. Because of concerns about pathogen growth on these food items at retail, the 2009 U.S. Food and Drug Administration Food Code established that cut leafy greens (lettuce, spinach, spring mix, cabbage, arugula, and kale) must have time and temperature controls for safety and hence should be kept at refrigerated temperatures (5°C or lower). The purpose of this study was to determine the temperature profiles of cut leafy greens in single-serving clamshell containers provided as part of the North Carolina School Lunch Program and to compare the two policies that North Carolina has in place to control the temperature of these products (the 3-day rule and time in lieu of temperature). Temperatures were recorded with data loggers in 24 schools during a 3-day period. In all cases, substantial temperature variability was found for these products, including temperatures above 5°C for at least 1 h on each of the 3 days. In some cases, temperatures reached above 5°C for more than 3 h throughout the serving time. The results demonstrate the importance of developing a protocol for continuous temperature monitoring of leafy greens served in school lunch programs.
1992-10-01
MSFC Test Engineer performing a functional test on the TES. The TES can be operated as a refrigerator, with a minimum set point temperature of 4.0 degrees C, or as an incubator, with a maximum set point temperature 40.0 degrees C of the set point. The TES can be set to maintain a constant temperature or programmed to change temperature settings over time, internal temperature recorded by a date logger.
NASA Astrophysics Data System (ADS)
Centurioni, Luca
2017-04-01
The Global Drifter Program is the principal component of the Global Surface Drifting Buoy Array, a branch of NOAA's Global Ocean Observing System and a scientific project of the Data Buoy Cooperation Panel (DBCP). The DBCP is an international program coordinating the use of autonomous data buoys to observe atmospheric and oceanographic conditions over ocean areas where few other measurements are taken. The Global Drifter Program maintains an array of over 1,250 Lagrangian drifters, reporting in near real-time and designed measure 15 m depth Lagrangian currents, sea surface temperature (SST) and sea level atmospheric pressure (SLP), among others, to fulfill the needs to observe the air-sea interface at temporal and spatial scales adequate to support short to medium-range weather forecasting, ocean state estimates and climate science. This overview talk will discuss the main achievements of the program, the main impacts for satellite SST calibration and validation, for numerical weather prediction, and it will review the main scientific findings based on the use of Lagrangian currents. Finally, we will present new developments in Lagrangian drifter technology, which include special drifters designed to measure sea surface salinity, wind and directional wave spectra. New opportunities for expanding the scope of the Global Drifter Program will be discussed.
NASA Astrophysics Data System (ADS)
Semerjyan, Vardan; Yuan, Tao
2011-04-01
Sodium (Na) Faraday filters based spectrometer is a relatively new instrument to study sodium nightglow as well as sodium and oxygen chemistry in the mesopause region. Successful spectrometer measurement demands highly accurate control of filter temperature. The ideal, long-term operation site for the Na spectrometer is an isolated location with minimum nocturnal sky background. Thus, the remote control of the filter temperature is a requirement for such operation, whereas current temperature controllers can only be operated manually. The proposed approach is aimed to not only enhance the temperature control, but also achieve spectrometer's remote and autonomous operation. In the meantime, the redesign should relief the burden of the cost for multi temperature controllers. The program will give to the operator flexibility in setting the operation temperatures of the Faraday filters, monitoring the temperature variations, and logging the data during the operation. Research will make diligent efforts to attach preliminary data analysis subroutine to the main control program. The real-time observation results will be posted online after the observation is completed. This approach also can be a good substitute for the temperature control system currently used to run the Lidar system at Utah State University (USU).
Microanalysis of vitrous char and associated polymers: reference and ancient assemblages
NASA Astrophysics Data System (ADS)
Allue, E.; Bonnamy, S.; Courty, M. M.; Gispert I Guirado, F.
2012-12-01
Formation of vitrous char that occur in ancient charcoal assemblages have remained unsolved. Laboratory experiments refuted vitrification to resulting from high temperature charring of green or resinous wood. This puzzling problem has been refreshed by showing the association to the charcoal and vitrous char of plastics that were originally supposed to only be produced by petroleum industry. Extraction of similar polymers within geological glassy products from cosmic airbursts has suggested impact processes to possibly forming the carbonaceous polymorphs. The pulverisation at the ground in the Angles village (French Eastern Pyrenees) following the 2011 August 2nd high altitude meteor explosion of exotic debris with vitrous char and polymers, just alike the puzzling ones of the geological and archaeological records, has provided potential reference materials. We present here their microanalysis by Environmental SEM with EDS, Raman micro-spectrometry and FTIR, XRD, TEM, ICP-MS and isotope analyses. The characterization helps elucidating how the carbonaceous polymorphs formed by transient heating and transient high pressure of atmospheric aerosols. Under TEM the vesicular, dense, vitrous char show high structural organization with a dense pattern of nano-sized graphitized domains, metals and mineral inclusions. The coupled Raman-ESEM has allowed identifying a complex pattern at micro scales of ordered "D" peak at 1320-1350 cm-1 and the graphitic, ordered peak at 1576-1590 cm-1, in association to amorphous and poorly graphitic ordered carbon. The later occurs within plant cells that have been extracted from the dense vitrous char by performing controlled combustion under nitrogen up to 1000°C. In contrast, the brittle, vesicular vitrous char and the polymers encountered at the rear of the pulverised airburst debris reveal to be formed of agglutinated micro spherules of amorphous carbon with rare crystallized carbon nano-domains and scattered mineral inclusions. They completely vaporised at 300°C under stepped-heating without leaving extractable residues. The link established between the structure of these exceptional carbon polymorphs and their forming processes provide diagnostic keys for interpreting vitrous carbon in ancient charcoal assemblage. The hardest ones offer reliable impact markers with their distinctive nanostructure produced by the transient high pressure and heating of carbonaceous aerosols by cosmic airbursts. In contrast, the weakly graphitised ones with distinctive plant structures would possibly express moderate effects of the airburst shock wave on vegetation at the ground. Thus micro-structural characterization of charcoal in archaeological assemblages would help tracing possible exploitation of blasted wood forest and related fossil fuel produced by ancient cosmic airbursts.
Wiese, Steffen; Teutenberg, Thorsten; Schmidt, Torsten C
2011-09-28
In the present work it is shown that the linear elution strength (LES) model which was adapted from temperature-programming gas chromatography (GC) can also be employed to predict retention times for segmented-temperature gradients based on temperature-gradient input data in liquid chromatography (LC) with high accuracy. The LES model assumes that retention times for isothermal separations can be predicted based on two temperature gradients and is employed to calculate the retention factor of an analyte when changing the start temperature of the temperature gradient. In this study it was investigated whether this approach can also be employed in LC. It was shown that this approximation cannot be transferred to temperature-programmed LC where a temperature range from 60°C up to 180°C is investigated. Major relative errors up to 169.6% were observed for isothermal retention factor predictions. In order to predict retention times for temperature gradients with different start temperatures in LC, another relationship is required to describe the influence of temperature on retention. Therefore, retention times for isothermal separations based on isothermal input runs were predicted using a plot of the natural logarithm of the retention factor vs. the inverse temperature and a plot of the natural logarithm of the retention factor vs. temperature. It could be shown that a plot of lnk vs. T yields more reliable isothermal/isocratic retention time predictions than a plot of lnk vs. 1/T which is usually employed. Hence, in order to predict retention times for temperature-gradients with different start temperatures in LC, two temperature gradient and two isothermal measurements have been employed. In this case, retention times can be predicted with a maximal relative error of 5.5% (average relative error: 2.9%). In comparison, if the start temperature of the simulated temperature gradient is equal to the start temperature of the input data, only two temperature-gradient measurements are required. Under these conditions, retention times can be predicted with a maximal relative error of 4.3% (average relative error: 2.2%). As an example, the systematic method development for an isothermal as well as a temperature gradient separation of selected sulfonamides by means of the adapted LES model is demonstrated using a pure water mobile phase. Both methods are compared and it is shown that the temperature-gradient separation provides some advantages over the isothermal separation in terms of limits of detection and analysis time. Copyright © 2011 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Sasaki, T.; Itai, Y.; Iwasawa, Y.
1997-11-01
For the purpose of utilizing ESDIAD as a real-time probe for surface processes, we have developed an instrument which can measure ESDIAD images and time of flight (TOF) spectra of desorbing ions in temperature-programmed surface processes. TOF measurements are carried out to identify the mass and to determine the kinetic energy distribution of the desorbed ions. This temperature-programmed (TP-) ESDIAD/TOF system was used to observe coadsorption layers of methylamine and CO on Ru(001) which have been previously studied by our group using LEED, TPD and HREELS, also drawing upon a comparison of findings with the coadsorption system of CO and ammonia. ESDIAD images acquired for temperature-programmed surface processes in real time were found to provide new insight into the dynamic behaviour of the coadsorption layers. As to the pure adsorption of ammonia and methylamine, the second and the first (chemisorbed) layers can be easily discriminated in their different ESD detection efficiency due to the difference in neutralization rate. The intensity change of H + ions with temperature shows the process of the decomposition of methylamine to be dependent on CO coverage. The intensity of O + originating from CO changes due to the change of CO adsorption site in the reaction process. The angular distribution of H + ions which correspond to CH2NH…Ru species appears at 250-300 K in the presence of high CO pre-coverage.
Optical Fiber High Temperature Sensor Instrumentation for Energy Intensive Industries
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cooper, Kristie L.; Wang, Anbo; Pickrell, Gary R.
2006-11-14
This report summarizes technical progress during the program “Optical Fiber High Temperature Sensor Instrumentation for Energy Intensive Industries”, performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech. The objective of this program was to use technology recently invented at Virginia Tech to develop and demonstrate the application of self-calibrating optical fiber temperature and pressure sensors to several key energy-intensive industries where conventional, commercially available sensors exhibit greatly abbreviated lifetimes due primarily to environmental degradation. A number of significant technologies were developed under this program, including • a laser bonded silicamore » high temperature fiber sensor with a high temperature capability up to 700°C and a frequency response up to 150 kHz, • the world’s smallest fiber Fabry-Perot high temperature pressure sensor (125 x 20 μm) with 700°C capability, • UV-induced intrinsic Fabry-Perot interferometric sensors for distributed measurement, • a single crystal sapphire fiber-based sensor with a temperature capability up to 1600°C. These technologies have been well demonstrated and laboratory tested. Our work plan included conducting major field tests of these technologies at EPRI, Corning, Pratt & Whitney, and Global Energy; field validation of the technology is critical to ensuring its usefulness to U.S. industries. Unfortunately, due to budget cuts, DOE was unable to follow through with its funding commitment to support Energy Efficiency Science Initiative projects and this final phase was eliminated.« less
Program Solicitation Number 86.1, Small Business Innovation Research Program.
1986-01-31
Temperature Heat Pipe Technology DESCRIPTION: Heat pipes have been shown to provide superior growth conditions for the growth of bulk semiconductor crystals... Heat pipes allow for the establishment of isothermal conditions over large areas. This thermal property controls the distribution of impurities, and...reliable high temperature heat pipes to operate at 1325 degrees C with inert overpressures of 60 atmospheres is required for the processing of III-V
Segregation effects during solidification in weightless melts
NASA Technical Reports Server (NTRS)
Li, C.; Gershinsky, M.
1974-01-01
The generalized problem of determining the temperature and solute concentration profiles during directional solidification of binary alloys with surface evaporation was mathematically formulated. Realistic initial and boundary conditions were defined, and a computer program was developed and checked out. The programs computes the positions of two moving boundaries, evaporation and solidification, and their velocities. Temperature and solute concentration profiles in the semiinfinite material body at selected instances of time are also computed.
Program For Joule-Thomson Analysis Of Mixed Cryogens
NASA Technical Reports Server (NTRS)
Jones, Jack A.; Lund, Alan
1994-01-01
JTMIX computer program predicts ideal and realistic properties of mixed gases at temperatures between 65 and 80 K. Performs Joule-Thomson analysis of any gaseous mixture of neon, nitrogen, various hydrocarbons, argon, oxygen, carbon monoxide, carbon dioxide, and hydrogen sulfide. When used in conjunction with DDMIX computer program of National Institute of Standards and Technology (NIST), JTMIX accurately predicts order-of-magnitude increases in Joule-Thomson cooling capacities occuring when various hydrocarbons added to nitrogen. Also predicts boiling temperature of nitrogen depressed from normal value to as low as 60 K upon addition of neon. Written in Turbo C.
Program Processes Thermocouple Readings
NASA Technical Reports Server (NTRS)
Quave, Christine A.; Nail, William, III
1995-01-01
Digital Signal Processor for Thermocouples (DART) computer program implements precise and fast method of converting voltage to temperature for large-temperature-range thermocouple applications. Written using LabVIEW software. DART available only as object code for use on Macintosh II FX or higher-series computers running System 7.0 or later and IBM PC-series and compatible computers running Microsoft Windows 3.1. Macintosh version of DART (SSC-00032) requires LabVIEW 2.2.1 or 3.0 for execution. IBM PC version (SSC-00031) requires LabVIEW 3.0 for Windows 3.1. LabVIEW software product of National Instruments and not included with program.
NASA Technical Reports Server (NTRS)
Haas, L. A., Sr.
1976-01-01
The Fail-Safe Abort System TEMPerature Analysis Program, (FASTEMP), user's manual is presented. This program was used to analyze fail-safe abort systems for an actively cooled hypersonic aircraft. FASTEMP analyzes the steady state or transient temperature response of a thermal model defined in rectangular, cylindrical, conical and/or spherical coordinate system. FASTEMP provides the user with a large selection of subroutines for heat transfer calculations. The various modes of heat transfer available from these subroutines are: heat storage, conduction, radiation, heat addition or generation, convection, and fluid flow.
RECOZ data reduction and analysis: Programs and procedures
NASA Technical Reports Server (NTRS)
Reed, E. I.
1984-01-01
The RECOZ data reduction programs transform data from the RECOZ photometer to ozone number density and overburden as a function of altitude. Required auxiliary data are the altitude profile versus time and for appropriate corrections to the ozone cross sections and scattering effects, air pressure and temperature profiles. Air temperature and density profiles may also be used to transform the ozone density versus geometric altitude to other units, such as to ozone partial pressure or mixing ratio versus pressure altitude. There are seven programs used to accomplish this: RADAR, LISTRAD, RAW OZONE, EDIT OZONE, MERGE, SMOOTH, and PROFILE.
Methods for structural design at elevated temperatures
NASA Technical Reports Server (NTRS)
Ellison, A. M.; Jones, W. E., Jr.; Leimbach, K. R.
1973-01-01
A procedure which can be used to design elevated temperature structures is discussed. The desired goal is to have the same confidence in the structural integrity at elevated temperature as the factor of safety gives on mechanical loads at room temperature. Methods of design and analysis for creep, creep rupture, and creep buckling are presented. Example problems are included to illustrate the analytical methods. Creep data for some common structural materials are presented. Appendix B is description, user's manual, and listing for the creep analysis program. The program predicts time to a given creep or to creep rupture for a material subjected to a specified stress-temperature-time spectrum. Fatigue at elevated temperature is discussed. Methods of analysis for high stress-low cycle fatigue, fatigue below the creep range, and fatigue in the creep range are included. The interaction of thermal fatigue and mechanical loads is considered, and a detailed approach to fatigue analysis is given for structures operating below the creep range.
Real-time aerodynamic heating and surface temperature calculations for hypersonic flight simulation
NASA Technical Reports Server (NTRS)
Quinn, Robert D.; Gong, Leslie
1990-01-01
A real-time heating algorithm was derived and installed on the Ames Research Center Dryden Flight Research Facility real-time flight simulator. This program can calculate two- and three-dimensional stagnation point surface heating rates and surface temperatures. The two-dimensional calculations can be made with or without leading-edge sweep. In addition, upper and lower surface heating rates and surface temperatures for flat plates, wedges, and cones can be calculated. Laminar or turbulent heating can be calculated, with boundary-layer transition made a function of free-stream Reynolds number and free-stream Mach number. Real-time heating rates and surface temperatures calculated for a generic hypersonic vehicle are presented and compared with more exact values computed by a batch aeroheating program. As these comparisons show, the heating algorithm used on the flight simulator calculates surface heating rates and temperatures well within the accuracy required to evaluate flight profiles for acceptable heating trajectories.
Estimating Arrhenius parameters using temperature programmed molecular dynamics.
Imandi, Venkataramana; Chatterjee, Abhijit
2016-07-21
Kinetic rates at different temperatures and the associated Arrhenius parameters, whenever Arrhenius law is obeyed, are efficiently estimated by applying maximum likelihood analysis to waiting times collected using the temperature programmed molecular dynamics method. When transitions involving many activated pathways are available in the dataset, their rates may be calculated using the same collection of waiting times. Arrhenius behaviour is ascertained by comparing rates at the sampled temperatures with ones from the Arrhenius expression. Three prototype systems with corrugated energy landscapes, namely, solvated alanine dipeptide, diffusion at the metal-solvent interphase, and lithium diffusion in silicon, are studied to highlight various aspects of the method. The method becomes particularly appealing when the Arrhenius parameters can be used to find rates at low temperatures where transitions are rare. Systematic coarse-graining of states can further extend the time scales accessible to the method. Good estimates for the rate parameters are obtained with 500-1000 waiting times.
Microwave brightness temperature of a windblown sea
NASA Technical Reports Server (NTRS)
Hall, F. G.
1972-01-01
A mathematical model is developed for the apparent temperature of the sea at all microwave frequencies. The model is a numerical model in which both the clear water structure and white water are accounted for as a function of wind speed. The model produces results similar to Stogryn's model at 19.35 GHz for wind speeds less than 8 m/sec; it can use radiosonde data to calculate atmospheric effects and can incorporate an empirically determined antenna gain pattern. The corresponding computer program is of modular design and the logic of the main program is capable of treating a horizontally inhomogeneous surface or atmosphere. It is shown that a variation of microwave brightness temperature with zenith angle is necessary to produce the wind sensitivity of the horizontally polarized brightness temperature; the variation of sky temperature with frequency is sufficient to produce a frequency dependent wind sensitivity.
Status of Post Irradiation Examination of FCAB and FCAT Irradiation Capsules
DOE Office of Scientific and Technical Information (OSTI.GOV)
Field, Kevin G.; Yamamoto, Yukinori; Howard, Richard H.
A series of irradiation programs are ongoing to address the need for determining the radiation tolerance of FeCrAl alloys. These irradiation programs, deemed the FCAT and FCAB irradiation programs, use the High Flux Isotope Reactor (HFIR) to irradiate second generation wrought FeCrAl alloys and early-generation powder-metallurgy (PM) oxide dispersion-strengthened (ODS) FeCrAl alloys. Irradiations have been or are being performed at temperatures of 200°C, 330°C, and 550°C from doses of 1.8 dpa up to 16 dpa. Preliminary post-irradiation examination (PIE) on low dose (<2 dpa) irradiation capsules of tensile specimens has been performed. Analysis of co-irradiated SiC thermometry have shown reasonablemore » matching between the nominal irradiation temperatures and the target irradiation temperatures. Room temperature tensile tests have shown typical radiation-induced hardening and embrittlement at irradiations of 200°C and 330°C, but a propensity for softening when irradiated to 550°C for the wrought alloys. The PM-ODS FeCrAl specimens showed less hardening compared to the wrought alloys. Future PIE includes high temperature tensile tests on the low dose irradiation capsules as well as the determination of reference fracture toughness transition temperature, T o, in alloys irradiated to 7 dpa and higher.« less
Functional Test on (TES) Thermal Enclosure System
NASA Technical Reports Server (NTRS)
1992-01-01
MSFC Test Engineer performing a functional test on the TES. The TES can be operated as a refrigerator, with a minimum set point temperature of 4.0 degrees C, or as an incubator, with a maximum set point temperature 40.0 degrees C of the set point. The TES can be set to maintain a constant temperature or programmed to change temperature settings over time, internal temperature recorded by a date logger.
NASA Technical Reports Server (NTRS)
Atkinson, W. H.; Cyr, M. A.; Strange, R. R.
1988-01-01
The report presents the final results of Tasks 1 and 2, Development of Sensors for Ceramic Components in Advanced Propulsion Systems (NASA program NAS3-25141). During Task 1, an extensive survey was conducted of sensor concepts which have the potential for measuring surface temperature, strain and heat flux on ceramic components for advanced propulsion systems. Each sensor concept was analyzed and evaluated under Task 2; sensor concepts were then recommended for further development. For temperature measurement, both pyrometry and thermographic phosphors are recommended for measurements up to and beyond the melting point of ceramic materials. For lower temperature test programs, the thin-film techniques offer advantages in the installation of temperature sensors. Optical strain measurement techniques are recommended because they offer the possibility of being useful at very high temperature levels. Techniques for the measurement of heat flux are recommended for development based on both a surface mounted sensor and the measurement of the temperature differential across a portion of a ceramic component or metallic substrate.
Programmable Calculators for Elementary Schools.
ERIC Educational Resources Information Center
Wayrik, John J.
1978-01-01
Instructions are given for using and programing programable calculators. Several problems and examples are given that include topics such as temperature conversion, estimation, and number operations. (MP)
Programming scale-free optics in disordered ferroelectrics.
Parravicini, Jacopo; Conti, Claudio; Agranat, Aharon J; DelRe, Eugenio
2012-06-15
Using the history dependence of a dipolar glass hosted in a compositionally disordered lithium-enriched potassium tantalate niobate (KTN:Li) crystal, we demonstrate scale-free optical propagation at tunable temperatures. The operating equilibration temperature is determined by previous crystal spiralling in the temperature/cooling-rate phase space.
Characterization of the Temperature Capabilities of Advanced Disk Alloy ME3
NASA Technical Reports Server (NTRS)
Gabb, Timothy P.; Telesman, Jack; Kantzos, Peter T.; OConnor, Kenneth
2002-01-01
The successful development of an advanced powder metallurgy disk alloy, ME3, was initiated in the NASA High Speed Research/Enabling Propulsion Materials (HSR/EPM) Compressor/Turbine Disk program in cooperation with General Electric Engine Company and Pratt & Whitney Aircraft Engines. This alloy was designed using statistical screening and optimization of composition and processing variables to have extended durability at 1200 F in large disks. Disks of this alloy were produced at the conclusion of the program using a realistic scaled-up disk shape and processing to enable demonstration of these properties. The objective of the Ultra-Efficient Engine Technologies disk program was to assess the mechanical properties of these ME3 disks as functions of temperature in order to estimate the maximum temperature capabilities of this advanced alloy. These disks were sectioned, machined into specimens, and extensively tested. Additional sub-scale disks and blanks were processed and selectively tested to explore the effects of several processing variations on mechanical properties. Results indicate the baseline ME3 alloy and process can produce 1300 to 1350 F temperature capabilities, dependent on detailed disk and engine design property requirements.
Wang, Fang; Yeung, David; Han, Jun; Semin, David; McElvain, James S; Cheetham, Janet
2008-03-01
We report the application of column temperature programs as a tool to examine unusual temperature-induced behaviors of polysaccharide chiral stationary phases (CSPs). Using dihydropyrimidinone (DHP) compounds as probes we observed the heating (10-50 degrees C) and cooling (50-10 degrees C) van't Hoff plots of retention factors and/or selectivities of DHP compounds were not superimposable on AD, IA, and AS-H columns solvated with ethanol (EtOH)/n-hexane (n-Hex) mobile phases. The plots were not superimposable on AD, IB, and AS-H columns solvated with 2-propanol (2-PrOH)/n-Hex mobile phases. The thermally induced path-dependant behaviors were caused by slow equilibration as evidenced by the disappearance of the hysteresis in the second heating to cooling cycle and in a cooling to heating cycle. From the step-temperature program (10-50-10 degrees C), only EtOH solvated AD and AS-H phases showed the change of retention factors and/or selectivities with time while only 2-PrOH solvated AS-H phase showed similar behaviors.
NASA Space Cryocooler Programs: A 2003 Overview
NASA Technical Reports Server (NTRS)
Ross, R. G., Jr.; Boyle, R. F.; Kittel, P.
2004-01-01
Mechanical cryocoolers represent a significant enabling technology for NASA's Earth and Space Science missions. An overview is presented of ongoing cryocooler activities within NASA in support of current flight projects, near-term flight instruments, and long-term technology development. NASA programs in Earth and space science observe a wide range of phenomena, from crop dynamics to stellar birth. Many of the instruments require cryogenic refrigeration to improve dynamic range, extend wavelength coverage, and enable the use of advanced detectors. Although, the largest utilization of coolers over the last decade has been for instruments operating at medium to high cryogenic temperatures (55 to 150 K), reflecting the relative maturity of the technology at these temperatures, important new developments are now focusing at the lower temperature range from 4 to 20 K in support of studies of the origin of the universe and the search for planets around distant stars. NASA's development of a 20K cryocooler for the European Planck spacecraft and its new Advanced Cryocooler Technology Development Program (ACTDP) for 6-18 K coolers are examples of the thrust to provide low temperature cooling for this class of missions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trexler, D.T.; Flynn, T.; Koenig, B.A.
1982-01-01
Geological, geophysical and geochemical surveys were used in conjunction with temperature gradient hole drilling to assess the geothermal resources in Pumpernickel Valley and Carlin, Nevada. This program is based on a statewide assessment of geothermal resources that was completed in 1979. The exploration techniques are based on previous federally-funded assessment programs that were completed in six other areas in Nevada and include: literature search and compilation of existing data, geologic reconnaissance, chemical sampling of thermal and non-thermal fluids, interpretation of satellite imagery, interpretation of low-sun angle aerial photographs, two-meter depth temperature probe survey, gravity survey, seismic survey, soil-mercury survey, andmore » temperature gradient drilling.« less
Advanced high temperature instrument for hot section research applications
NASA Technical Reports Server (NTRS)
Englund, D. R.; Seasholtz, R. G.
1989-01-01
Programs to develop research instrumentation for use in turbine engine hot sections are described. These programs were initiated to provide improved measurements capability as support for a multidisciplinary effort to establish technology leading to improved hot section durability. Specific measurement systems described here include heat flux sensors, a dynamic gas temperature measuring system, laser anemometry for hot section applications, an optical system for viewing the interior of a combustor during operation, thin film sensors for surface temperature and strain measurements, and high temperature strain measuring systems. The state of development of these sensors and measuring systems is described, and, in some cases, examples of measurements made with these instruments are shown. Work done at the NASA Lewis Research Center and at various contract and grant facilities is covered.
A single dose of cocaine enhances prospective memory performance.
Hutten, Nadia Rpw; Kuypers, Kim Pc; van Wel, Janelle Hp; Theunissen, Eef L; Toennes, Stefan W; Verkes, Robbert-Jan; Ramaekers, Johannes G
2018-06-01
Prospective memory is the ability to recall intended actions or events at the right time or in the right context. While cannabis is known to impair prospective memory, the acute effect of cocaine is unknown. In addition, it is not clear whether changes in prospective memory represent specific alterations in memory processing or result from more general effects on cognition that spread across multiple domains such as arousal and attention. The main objective of the study was, therefore, to determine whether drug-induced changes in prospective memory are memory specific or associated with more general drug-induced changes in attention and arousal. A placebo-controlled, three-way, cross-over study including 15 regular poly-drug users was set up to test the influence of oral cocaine (300 mg) and vaporised cannabis (300+150 'booster' µg/kg bodyweight) on an event-based prospective memory task. Attentional performance was assessed using a divided attention task and subjective arousal was assessed with the Profile of Mood States questionnaire. Results showed that cocaine enhanced prospective memory, attention and arousal. Mean performance of prospective memory and attention, as well as levels of arousal were lowest during treatment with cannabis as compared with placebo and cocaine as evinced by a significantly increased trend across treatment conditions. Prospective memory performance was only weakly positively associated to measures of attention and arousal. Together, these results indicate that cocaine enhancement of prospective memory performance cannot be fully explained by parallel changes in arousal and attention levels, and is likely to represent a direct change in the neural network underlying prospective memory.
Photolasertherapy for the treatment of infections in neurosurgery: experimental and clinical study
NASA Astrophysics Data System (ADS)
Lombard, Gian F.
1996-12-01
At the first time, the CO2 laser was utilised in infective neurosurgical pathology as a surgical cutting instrument to remove inflammatory pseudomembranes in chronic osteomyelitis, and as a vaporising instmment on the dura mater surface. Successively, the instrument, defocused and at a low power, was used for prolonged and diffuse photo coagulation ofthe surgical cavity, particularly, ofthe dural surface and ofthe osteomyelitic bone edges, with the aim to sterilise tissues. So, we saw a shortening of the average time of wound healing and a lack of recurrence of the septic pathology. Then, we have treated, with CO2 laser, intracranial infective pathology: i.e. primary abscesses, capsulated or not, circumscribed purulent encephalitis, secondary abscesses in surgical cavities (patients operated for intracranial hematomas and tumors). In these cases we have obtained a lack of septic recurrences and an improvement ofneurological post-operative course. Thank to these results, we have continued to use laser in infective pathology; for giving an experimental support to these results we have carried on researches in vivo (on the experimental animal) to see the interaction between the laser and inflammatory tissue, and in vitro (on bacterial culture: in solid and liquid media) to see the laser effect on the bacterial cell. The bacterial cell has been also sensibiized to the photo dynamic effect of the laser (Argon, He-Ne), with hematoporphyrin. The goal of these experiments is to understand the role of thermal, photochemical, and mechanic resonance laser effects in the interaction between laser radiation and bacterial cell.
Olivi, Giovanni; Angiero, Francesca; Benedicenti, Stefano; Iaria, Giuseppe; Signore, Antonio; Kaitsas, Vassilios
2010-11-01
The study investigated the influence of varying amounts of air/water spray and the energy used by an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) 2,780 nm laser when treating dental tissues. The morphological effects produced by the laser interaction on healthy human enamel were evaluated by scanning electron microscopy (SEM). The vestibular and lingual surfaces of ten molars were treated with laser at different power settings; each surface was subdivided into cervical, median, and occlusal parts and treated with different proportions of water spray; the series contained 60 tooth portions. Treatment differed in terms of power setting and air/water percentage. All specimens were then subjected to dehydration and metallisation. At SEM evaluation, the classic aspect of laser-treated enamel was visible: grooves, flakes, shelves and sharp edges, indicative of micro-explosion rather than melting. Vaporisation of the tissue created a clear delimitation from surrounding healthy tissue, with partial respect to the prismatic structure of the treated enamel. The aspect of the enamel was rarely type 1 Silverstone but more frequently type 2 or 3, with prismatic structure not respected and/or completely disordered. These morphological differences appeared to be correlated with the inclination of the laser beam aimed at the enamel prisms and with the percentage of air/water used. The laser system analysed showed itself to be effective at removing human dental enamel. The results appeared to be closely correlated with the variation of the percentage of the laser's water-air spray.
Practical considerations in medical cannabis administration and dosing.
MacCallum, Caroline A; Russo, Ethan B
2018-03-01
Cannabis has been employed medicinally throughout history, but its recent legal prohibition, biochemical complexity and variability, quality control issues, previous dearth of appropriately powered randomised controlled trials, and lack of pertinent education have conspired to leave clinicians in the dark as to how to advise patients pursuing such treatment. With the advent of pharmaceutical cannabis-based medicines (Sativex/nabiximols and Epidiolex), and liberalisation of access in certain nations, this ignorance of cannabis pharmacology and therapeutics has become untenable. In this article, the authors endeavour to present concise data on cannabis pharmacology related to tetrahydrocannabinol (THC), cannabidiol (CBD) et al., methods of administration (smoking, vaporisation, oral), and dosing recommendations. Adverse events of cannabis medicine pertain primarily to THC, whose total daily dose-equivalent should generally be limited to 30mg/day or less, preferably in conjunction with CBD, to avoid psychoactive sequelae and development of tolerance. CBD, in contrast to THC, is less potent, and may require much higher doses for its adjunctive benefits on pain, inflammation, and attenuation of THC-associated anxiety and tachycardia. Dose initiation should commence at modest levels, and titration of any cannabis preparation should be undertaken slowly over a period of as much as two weeks. Suggestions are offered on cannabis-drug interactions, patient monitoring, and standards of care, while special cases for cannabis therapeutics are addressed: epilepsy, cancer palliation and primary treatment, chronic pain, use in the elderly, Parkinson disease, paediatrics, with concomitant opioids, and in relation to driving and hazardous activities. Copyright © 2018 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.
Dynamic gas temperature measurement system. Volume 2: Operation and program manual
NASA Technical Reports Server (NTRS)
Purpura, P. T.
1983-01-01
The hot section technology (HOST) dynamic gas temperature measurement system computer program acquires data from two type B thermocouples of different diameters. The analysis method determines the in situ value of an aerodynamic parameter T, containing the heat transfer coefficient from the transfer function of the two thermocouples. This aerodynamic parameter is used to compute a fequency response spectrum and compensate the dynamic portion of the signal of the smaller thermocouple. The calculations for the aerodynamic parameter and the data compensation technique are discussed. Compensated data are presented in either the time or frequency domain, time domain data as dynamic temperature vs time, or frequency domain data.
NASA Technical Reports Server (NTRS)
Kull, F. R.
1975-01-01
The results of a program to develop a lightweight high temperature reusable fastening system for aerospace vehicle thermal protection system applications are documented. This feasibility program resulted in several fastener innovations which will meet the specific needs of the heat shield application. Three systems were designed from Hayes 188 alloy and tested by environmental exposure and residual mechanical properties. The designs include a clinch stud with a collar retainer, a weld stud with a split ring retainer, and a caged stud with a collar retainer. The results indicated that a lightweight, reusable, high temperature fastening system can be developed for aerospace vehicle application.
NASA Technical Reports Server (NTRS)
Stocks, Dana R.
1986-01-01
The Dynamic Gas Temperature Measurement System compensation software accepts digitized data from two different diameter thermocouples and computes a compensated frequency response spectrum for one of the thermocouples. Detailed discussions of the physical system, analytical model, and computer software are presented in this volume and in Volume 1 of this report under Task 3. Computer program software restrictions and test cases are also presented. Compensated and uncompensated data may be presented in either the time or frequency domain. Time domain data are presented as instantaneous temperature vs time. Frequency domain data may be presented in several forms such as power spectral density vs frequency.
High-Temperature Polymer Composites Tested for Hypersonic Rocket Combustor Backup Structure
NASA Technical Reports Server (NTRS)
Sutter, James K.; Shin, E. Eugene; Thesken, John C.; Fink, Jeffrey E.
2005-01-01
Significant component weight reductions are required to achieve the aggressive thrust-toweight goals for the Rocket Based Combined Cycle (RBCC) third-generation, reusable liquid propellant rocket engine, which is one possible engine for a future single-stage-toorbit vehicle. A collaboration between the NASA Glenn Research Center and Boeing Rocketdyne was formed under the Higher Operating Temperature Propulsion Components (HOTPC) program and, currently, the Ultra-Efficient Engine Technology (UEET) Project to develop carbon-fiber-reinforced high-temperature polymer matrix composites (HTPMCs). This program focused primarily on the combustor backup structure to replace all metallic support components with a much lighter polymer-matrixcomposite- (PMC-) titanium honeycomb sandwich structure.
NASA Technical Reports Server (NTRS)
Grana, D. C.
1979-01-01
The results of two research programs to determine the optimum detector design for measuring fecal coliforms in saline waters for operational systems are presented. One program was concerned with the effects of temperature and salinity on endpoint response time, and the other, the interaction between electrode configurations and the test organisms. Test results show that the endpoint response time is related to salinity and seawater temperature; however, these results can be minimized by the correct choice of growth media. Electrode configurations were developed from stainless steel, Parlodion-coated stainless steel, and platinum that circumvented problems associated with the commercial redox electrodes.
System for the growth of bulk SiC crystals by modified CVD techniques
NASA Technical Reports Server (NTRS)
Steckl, Andrew J.
1994-01-01
The goal of this program was the development of a SiC CVD growth of films thick enough to be useful as pseudo-substrates. The cold-walled CVD system was designed, assembled, and tested. Extrapolating from preliminary evaluation of SiC films grown in the system at relatively low temperatures indicates that the growth rate at the final temperatures will be high enough to make our approach practical. Modifications of the system to allow high temperature growth and cleaner growth conditions are in progress. This program was jointly funded by Wright Laboratory, Materials Directorate and NASA LeRC and monitored by NASA.
2016-06-01
ASSIGNED DISTRIBUTION STATEMENT. *//Signature// //Signature// BRIAN T. GOCKEL MICHAEL S. BROWN, Chief Program Manager Hypersonic Sciences Branch...Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington...STATEMENT A: Approved for public release. Distribution is unlimited. Figure 3. Room-Temperature High-Speed DIC Tensile Setup A slack adapter was
Development of Thin Solar Cells for Space Applications at NASA Glenn Research Center
NASA Technical Reports Server (NTRS)
Dickman, John E.; Hepp, Aloysius; Banger, Kulbinder K.; Harris, Jerry D.; Jin, Michael H.
2003-01-01
NASA GRC Thin Film Solar Cell program is developing solar cell technologies for space applications which address two critical metrics: higher specific power (power per unit mass) and lower launch stowed volume. To be considered for space applications, an array using thin film solar cells must offer significantly higher specific power while reducing stowed volume compared to the present technologies being flown on space missions, namely crystalline solar cells. The NASA GRC program is developing single-source precursors and the requisite deposition hardware to grow high-efficiency, thin-film solar cells on polymer substrates at low deposition temperatures. Using low deposition temperatures enables the thin film solar cells to be grown on a variety of polymer substrates, many of which would not survive the high temperature processing currently used to fabricate thin film solar cells. The talk will present the latest results of this research program.
NASA Technical Reports Server (NTRS)
Clark, E. C.
1975-01-01
Thruster valve assemblies (T/VA's) were subjected to the development test program for the combined JPL Low-Cost Standardized Spacecraft Equipment (LCSSE) and Mariner Jupiter/Saturn '77 spacecraft (MJS) programs. The development test program was designed to achieve the following program goals: (1) demonstrate T/VA design compliance with JPL Specifications, (2) to conduct a complete performance Cf map of the T/VA over the full operating range of environment, (3) demonstrate T/VA life capability and characteristics of life margin for steady-state limit cycle and momentum wheel desaturation duty cycles, (4) verification of structural design capability, and (5) generate a computerized performance model capable of predicting T/VA operation over pressures ranging from 420 to 70 psia, propellant temperatures ranging from 140 F to 40 F, pulse widths of 0.008 to steady-state operation with unlimited duty cycle capability, and finally predict the transient performance associated with reactor heatup during any given duty cycle, start temperature, feed pressure, and propellant temperature conditions.
Tropical Ocean Global Atmosphere (TOGA) Meteorological and Oceanographic Data Sets for 1985 and 1986
NASA Technical Reports Server (NTRS)
Halpern, D.; Ashby, H.; Finch, C.; Smith, E.; Robles, J.
1990-01-01
The Tropical Ocean Global Atmosphere (TOGA) Program is a component of the World Meteorological Organization (WMO)/International Council of Scientific Unions (ICSU) World Climate Research Program (WCRP). One of the objectives of TOGA, which began in 1985, is to determine the limits of predictability of monthly mean sea surface temperature variations in tropical regions. The TOGA program created a raison d'etre for an explosive growth of the tropical ocean observing system and a substantial improvement in numerical simulations from atmospheric and oceanic general circulation models. Institutions located throughout the world are involved in the TOGA-distributed active data archive system. The diverse TOGA data sets for 1985 and 1986, including results from general circulation models, are included on a CD-ROM. Variables on the CD-ROM are barometric pressure, surface air temperature, dewpoint temperature Cartesian components of surface wind, surface sensible and latent heat fluxes,Cartesian components of surface wind stress and of an index of surface wind stress, sea level, sea surface temperature, and depth profiles of temperature and current in the upper ocean. Some data sets are global in extent, some are regional and cover portions of an ocean basin. Data on the CD-ROM can be extracted with an Apple Macintosh or an IBM PC.
Electronics for Low Temperature Space Exploration Missions
NASA Technical Reports Server (NTRS)
Patterson, Richard L.; Hammoud, Ahmad; Elbuluk, Malik
2007-01-01
Exploration missions to outer planets and deep space require spacecraft, probes, and on-board data and communication systems to operate reliably and efficiently under severe harsh conditions. On-board electronics, in particular those in direct exposures to the space environment without any shielding or protection, will encounter extreme low temperature and thermal cycling in their service cycle in most of NASA s upcoming exploration missions. For example, Venus atmosphere, Jupiter atmosphere, Moon surface, Pluto orbiter, Mars, comets, Titan, Europa, and James Webb Space Telescope all involve low-temperature surroundings. Therefore, electronics for space exploration missions need to be designed for operation under such environmental conditions. There are ongoing efforts at the NASA Glenn Research Center (GRC) to establish a database on the operation and reliability of electronic devices and circuits under extreme temperature operation for space applications. This work is being performed under the Extreme Temperature Electronics Program with collaboration and support of the NASA Electronic Parts and Packaging (NEPP) Program. The results of these investigations will be used to establish safe operating areas and to identify degradation and failure modes, and the information will be disseminated to mission planners and system designers for use as tools for proper part selection and in risk mitigation. An overview of this program along with experimental data will be presented.
Martin, Thomas E.; Ton, Riccardo; Oteyza, Juan C.
2018-01-01
Understanding intrinsic (physiological) and extrinsic (e.g., temperature) causes of variation in embryonic development time (incubation period) is important because they can have different impacts on individual quality. Robert Ricklefs and colleagues have argued that longer incubation periods result primarily from intrinsic physiological programs that increase individual quality and adult survival. They claim that incubation periods are largely invariant and that extrinsic factors like temperature have little impact. We have argued that adult survival may be a cause rather than a consequence of much of the variation in embryonic development time. A reduction in extrinsic sources of annual adult mortality (e.g., migration, predation, nonbreeding-season mortality) favors reduced parental effort during incubation to minimize costs to future reproduction and survival. Reduced parental effort, in turn, manifests as cooler average egg temperatures that yield longer incubation periods. Ricklefs and colleagues mischaracterized our hypothesis and deconstructed their own incorrect version, while also making some incorrect statements. We show that reevaluation of previous evidence provided by this group actually supports a role of egg temperature for the variation in incubation periods. We also summarize other observational and experimental evidence that incubation periods are not invariant and that egg temperature has a strong causal influence on variation within and among species. In fact, egg temperature explains ∼60% of the difference in incubation periods among species. The remaining ∼40% reflects intrinsic physiological programs and other factors, potentially providing intrinsic benefits. Ultimately, annual adult mortality explains substantial variation in parental effort and egg temperature, and the latter strongly explains variation in incubation periods. Both intrinsic programs and extrinsic temperature effects need to be considered in attempts to understand incubation strategies.
Teutenberg, T; Goetze, H-J; Tuerk, J; Ploeger, J; Kiffmeyer, T K; Schmidt, K G; Kohorst, W gr; Rohe, T; Jansen, H-D; Weber, H
2006-05-05
A specially designed heating system for temperature-programmed HPLC was developed based on experimental measurements of eluent temperature inside a stainless steel capillary using a very thin thermocouple. The heating system can be operated at temperatures up to 225 degrees C and consists of a preheating, a column heating and a cooling unit. Fast cycle times after a temperature gradient can be realized by an internal silicone oil bath which cools down the preheating and column heating unit. Long-term thermal stability of a polybutadiene-coated zirconium dioxide column has been evaluated using a tubular oven in which the column was placed. The packing material was stable after 50h of operation at 185 degrees C. A mixture containing four steroids was separated at ambient conditions using a mobile phase of 25% acetonitrile:75% deionized water and a mobile phase of pure deionized water at 185 degrees C using the specially designed heating system and the PBD column. Analysis time could be drastically reduced from 17 min at ambient conditions and a flow rate of 1 mL/min to only 1.2 min at 185 degrees C and a flow rate of 5 mL/min. At these extreme conditions, no thermal mismatch was observed and peaks were not distorted, thus underlining the performance of the developed heating system. Temperature programming was performed by separating cytostatic and antibiotic drugs with a temperature gradient using only water as the mobile phase. In contrast to an isocratic elution of this mixture at room temperature, overall analysis time could be reduced two-fold from 20 to 10 min.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martin, P.C.; DePoorter, G.L.; Munoz, D.R.
1991-02-01
We have initiated a three phase investigation of the development of high performance refractory fibers with enhanced insulating properties and longer usable lifetimes. This report presents the results of the first phase of the study, performed from Aug. 1989 through Feb. 1991, which shows that significant energy saving are possible through the use of high temperature insulating fibers that better retain their efficient insulating properties during the service lifetime of the fibers. The remaining phases of this program include the pilot scale development and then full scale production feasibility development and evaluation of enhanced high temperature refractory insulting fibers. Thismore » first proof of principle phase of the program presents a summary of the current use patterns of refractory fibers, a laboratory evaluation of the high temperature performance characteristics of selected typical refractory fibers and an analysis of the potential energy savings through the use of enhanced refractory fibers. The current use patterns of refractory fibers span a wide range of industries and high temperature furnaces within those industries. The majority of high temperature fiber applications are in furnaces operating between 2000 and 26000{degrees}F. The fibers used in furnaces operating within this range provide attractive thermal resistance and low thermal storage at reasonable cost. A series of heat treatment studies performed for this phase of the program has shown that the refractory fibers, as initially manufactured, have attractive thermal conductivities for high temperature applications but the fibers go through rapid devitrification and subsequent crystal growth upon high temperature exposure. Development of improved fibers, maintaining the favorable characteristics of the existing as-manufactured fibers, could save between 1 and 4% of the energy consumed in high temperature furnaces using refractory fibers.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Binney, E.J.
LION4 is a computer program for calculating one-, two-, or three-dimensional transient and steady-state temperature distributions in reactor and reactor plant components. It is used primarily for thermal-structural analyses. It utilizes finite difference techniques with first-order forward difference integration and is capable of handling a wide variety of bounding conditions. Heat transfer situations accommodated include forced and free convection in both reduced and fully-automated temperature dependent forms, coolant flow effects, a limited thermal radiation capability, a stationary or stagnant fluid gap, a dual dependency (temperature difference and temperature level) heat transfer, an alternative heat transfer mode comparison and selection facilitymore » combined with heat flux direction sensor, and any form of time-dependent boundary temperatures. The program, which handles time and space dependent internal heat generation, can also provide temperature dependent material properties with limited non-isotropic properties. User-oriented capabilities available include temperature means with various weightings and a complete heat flow rate surveillance system.CDC6600,7600;UNIVAC1108;IBM360,370; FORTRAN IV and ASCENT (CDC6600,7600), FORTRAN IV (UNIVAC1108A,B and IBM360,370); SCOPE (CDC6600,7600), EXEC8 (UNIVAC1108A,B), OS/360,370 (IBM360,370); The CDC6600 version plotter routine LAPL4 is used to produce the input required by the associated CalComp plotter for graphical output. The IBM360 version requires 350K for execution and one additional input/output unit besides the standard units.« less
High-temperature MIRAGE XL (LFRA) IRSP system development
NASA Astrophysics Data System (ADS)
McHugh, Steve; Franks, Greg; LaVeigne, Joe
2017-05-01
The development of very-large format infrared detector arrays has challenged the IR scene projector community to develop larger-format infrared emitter arrays. Many scene projector applications also require much higher simulated temperatures than can be generated with current technology. This paper will present an overview of resistive emitterbased (broadband) IR scene projector system development, as well as describe recent progress in emitter materials and pixel designs applicable for legacy MIRAGE XL Systems to achieve apparent temperatures >1000K in the MWIR. These new high temperature MIRAGE XL (LFRA) Digital Emitter Engines (DEE) will be "plug and play" equivalent with legacy MIRAGE XL DEEs, the rest of the system is reusable. Under the High Temperature Dynamic Resistive Array (HDRA) development program, Santa Barbara Infrared Inc. (SBIR) is developing a new infrared scene projector architecture capable of producing both very large format (>2k x 2k) resistive emitter arrays and improved emitter pixel technology capable of simulating very high apparent temperatures. During earlier phases of the program, SBIR demonstrated materials with MWIR apparent temperatures in excess of 1500 K. These new emitter materials can be utilized with legacy RIICs to produce pixels that can achieve 7X the radiance of the legacy systems with low cost and low risk. A 'scalable' Read-In Integrated Circuit (RIIC) is also being developed under the same HDRA program to drive the high temperature pixels. This RIIC will utilize through-silicon via (TSV) and Quilt Packaging (QP) technologies to allow seamless tiling of multiple chips to fabricate very large arrays, and thus overcome the yield limitations inherent in large-scale integrated circuits. These quilted arrays can be fabricated in any N x M size in 512 steps.
Computer program determines gas flow rates in piping systems
NASA Technical Reports Server (NTRS)
Franke, R.
1966-01-01
Computer program calculates the steady state flow characteristics of an ideal compressible gas in a complex piping system. The program calculates the stagnation and total temperature, static and total pressure, loss factor, and forces on each element in the piping system.
2014 Low-Temperature and Coproduced Geothermal Resources Fact Sheet
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tim Reinhardt, Program Manager
2014-09-01
As a growing sector of geothermal energy development, the Low-Temperature Program supports innovative technologies that enable electricity production and cascaded uses from geothermal resources below 300° Fahrenheit.
Automatic control of finite element models for temperature-controlled radiofrequency ablation.
Haemmerich, Dieter; Webster, John G
2005-07-14
The finite element method (FEM) has been used to simulate cardiac and hepatic radiofrequency (RF) ablation. The FEM allows modeling of complex geometries that cannot be solved by analytical methods or finite difference models. In both hepatic and cardiac RF ablation a common control mode is temperature-controlled mode. Commercial FEM packages don't support automating temperature control. Most researchers manually control the applied power by trial and error to keep the tip temperature of the electrodes constant. We implemented a PI controller in a control program written in C++. The program checks the tip temperature after each step and controls the applied voltage to keep temperature constant. We created a closed loop system consisting of a FEM model and the software controlling the applied voltage. The control parameters for the controller were optimized using a closed loop system simulation. We present results of a temperature controlled 3-D FEM model of a RITA model 30 electrode. The control software effectively controlled applied voltage in the FEM model to obtain, and keep electrodes at target temperature of 100 degrees C. The closed loop system simulation output closely correlated with the FEM model, and allowed us to optimize control parameters. The closed loop control of the FEM model allowed us to implement temperature controlled RF ablation with minimal user input.
Grall; Leonard; Sacks
2000-02-01
Recent advances in column heating technology have made possible very fast linear temperature programming for high-speed gas chromatography. A fused-silica capillary column is contained in a tubular metal jacket, which is resistively heated by a precision power supply. With very rapid column heating, the rate of peak-capacity production is significantly enhanced, but the total peak capacity and the boiling-point resolution (minimum boiling-point difference required for the separation of two nonpolar compounds on a nonpolar column) are reduced relative to more conventional heating rates used with convection-oven instruments. As temperature-programming rates increase, elution temperatures also increase with the result that retention may become insignificant prior to elution. This results in inefficient utilization of the down-stream end of the column and causes a loss in the rate of peak-capacity production. The rate of peak-capacity production is increased by the use of shorter columns and higher carrier gas velocities. With high programming rates (100-600 degrees C/min), column lengths of 6-12 m and average linear carrier gas velocities in the 100-150 cm/s range are satisfactory. In this study, the rate of peak-capacity production, the total peak capacity, and the boiling point resolution are determined for C10-C28 n-alkanes using 6-18 m long columns, 50-200 cm/s average carrier gas velocities, and 60-600 degrees C/min programming rates. It was found that with a 6-meter-long, 0.25-mm i.d. column programmed at a rate of 600 degrees C/min, a maximum peak-capacity production rate of 6.1 peaks/s was obtained. A total peak capacity of about 75 peaks was produced in a 37-s long separation spanning a boiling-point range from n-C10 (174 degrees C) to n-C28 (432 degrees C).
Second topical conference on high-temperature plasma diagnostics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jahoda, F.C.; Freese, K.B.
1978-02-01
This report contains the program and abstracts of papers presented at the Second American Physical Society Topical Conference on High Temperature Plasma Diagnostics, March 1-3, 1978, Santa Fe, New Mexico.
Epstein, Richard H; Dexter, Franklin; Hofer, Ira S; Rodriguez, Luis I; Schwenk, Eric S; Maga, Joni M; Hindman, Bradley J
2018-02-01
Perioperative hypothermia may increase the incidences of wound infection, blood loss, transfusion, and cardiac morbidity. US national quality programs for perioperative normothermia specify the presence of at least 1 "body temperature" ≥35.5°C during the interval from 30 minutes before to 15 minutes after the anesthesia end time. Using data from 4 academic hospitals, we evaluated timing and measurement considerations relevant to the current requirements to guide hospitals wishing to report perioperative temperature measures using electronic data sources. Anesthesia information management system databases from 4 hospitals were queried to obtain intraoperative temperatures and intervals to the anesthesia end time from discontinuation of temperature monitoring, end of surgery, and extubation. Inclusion criteria included age >16 years, use of a tracheal tube or supraglottic airway, and case duration ≥60 minutes. The end-of-case temperature was determined as the maximum intraoperative temperature recorded within 30 minutes before the anesthesia end time (ie, the temperature that would be used for reporting purposes). The fractions of cases with intervals >30 minutes between the last intraoperative temperature and the anesthesia end time were determined. Among the hospitals, averages (binned by quarters) of 34.5% to 59.5% of cases had intraoperative temperature monitoring discontinued >30 minutes before the anesthesia end time. Even if temperature measurement had been continued until extubation, averages of 5.9% to 20.8% of cases would have exceeded the allowed 30-minute window. Averages of 8.9% to 21.3% of cases had end-of-case intraoperative temperatures <35.5°C (ie, a quality measure failure). Because of timing considerations, a substantial fraction of cases would have been ineligible to use the end-of-case intraoperative temperature for national quality program reporting. Thus, retrieval of postanesthesia care unit temperatures would have been necessary. A substantive percentage of cases had end-of-case intraoperative temperatures below the 35.5°C threshold, also requiring postoperative measurement to determine whether the quality measure was satisfied. Institutions considering reporting national quality measures for perioperative normothermia should consider the technical and logistical issues identified to achieve a high level of compliance based on the specified regulatory language.
Temperature-dependent Study of Isobutanol Decomposition
2012-11-01
dimensional Al2O3 alumina CO2 carbon dioxide FTIR Fourier transform infrared Pd palladium Rh rhodium TPD temperature-programmed desorption TPO...that increasing temperature promotes aldehyde formation on the surface of each catalyst. In addition, it is shown that palladium (Pd) activates the...formation of aldehydes and CO2 at a lower temperature than a rhodium (Rh) catalyst. 15. SUBJECT TERMS Isobutanol, FTIR, spectroscopy 16. SECURITY
Near-room-temperature Mid-infrared Photoconductor Signal and Noise Characterization
2012-09-01
Near-room-temperature Mid-infrared Photoconductor Signal and Noise Characterization by Justin R. Bickford, Neal K. Bambha, and Wayne H. Chang...Adelphi, MD 20783-1197 ARL-TR-6169 September 2012 Near-room-temperature Mid-infrared Photoconductor Signal and Noise Characterization...temperature Mid-infrared Photoconductor Signal and Noise Characterization 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6
The Performance of PS400 Subjected to Sliding Contact at Temperatures from 260 to 927 deg C
2016-09-14
contact can be one of the most challenging tribological problems confronting today’s designers . In an attempt to provide a possible solution a test program...are not to be construed as an official Department of the Army position unless so designated by other authorized documents. Citation of...attempt to provide a possible solution a test program was initiated to evaluate PS400, a recently patented, high-temperature solid lubricant coating
Cooled High-Temperature Radial Turbine Program. Phase 2
1992-05-01
proposed for advanced engines with high power-to-weight and inproved SFC requirements. The addition of cooling to the blades of a metal radial turbine ...4 secl/2 ) 62.2 Blade - jet Speed Ratio 0.66 Adiabatic Efficiency (T-to-T, %) 87.0 Cooling flows for the gasifier turbine section are set at 5.7%. The...Way Cincinnati, OH 45215-6301 85 COOLED HIGH-TEMPERATURE RADIAL TURBINE PROGRAM DISTRIBUTION LIST Number Qf Copies General Electric Aircraft Engines
RDHWT/MARIAH II Hypersonic Wind Tunnel Research Program
2008-09-01
Diagnostics Dr. Gary Brown – Gas Dynamics Dr. Ihab Girgis – Modeling Dr. Dennis Mansfield – Experimental Ring Technical Services Dr. Leon Ring – Systems...wind tunnel (MSHWT) with Mach 8 to 15, true -temperature flight test capabilities. This research program was initiated in fiscal year (FY) 1998 and is...Force test capabilities that exist today. Performance goals of the MSHWT are true temperature, Mach 8 to 15, dynamic pressure of 500 to 2000 psf (24 to
An efficient annealing in Boltzmann machine in Hopfield neural network
NASA Astrophysics Data System (ADS)
Kin, Teoh Yeong; Hasan, Suzanawati Abu; Bulot, Norhisam; Ismail, Mohammad Hafiz
2012-09-01
This paper proposes and implements Boltzmann machine in Hopfield neural network doing logic programming based on the energy minimization system. The temperature scheduling in Boltzmann machine enhancing the performance of doing logic programming in Hopfield neural network. The finest temperature is determined by observing the ratio of global solution and final hamming distance using computer simulations. The study shows that Boltzmann Machine model is more stable and competent in term of representing and solving difficult combinatory problems.
Programmed temperature gasification study. Final report, October 1, 1979-November 30, 1980
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spoon, M.J.; Gardner, M.P.; Starkovich, J.A.
An experimental, modeling and conceptual engineering analysis study has been performed to assess the feasibility of TRW's Programmed Temperature Gasification (PTG) concept for carbonizing caking coals without severe agglomeration. The concept involves control of carbonizing heating rate to maintain metaplast concentration at a level equal to or slightly below that which causes agglomeration. The experimental studies required the contruction of a novel programmed temperature, elevated pressure, hot stage video microscope for observation of coal particle changes during heating. This system was used to develop a minimum-time heating schedule capable of carbonizing the coal at elevated pressures in the presence ofmore » hydrogen without severe agglomeration. Isothermal fixed heating rate data for a series of coals were subsequently used to calibrate and verify the mathematical model for the PTG process. These results showed good correlation between experimental data and mathematical predictions. Commercial application of the PTG concept to batch, moving bed and fluid bed processing schemes was then evaluated. Based on the calibrated model programmed temperature gasification of the coal without severe agglomeration could be carried out on a commercial batch reaction in 4 to 12 minutes. The next step in development of the PTG concept for commercial application would require testing on a bench scale (3-inch diameter) gasifier coupled with a full commercial assessment to determine size and cost of various gasification units.« less
Simulation of Propagation of Compartment Fire on Building Facades
NASA Astrophysics Data System (ADS)
Simion, A.; Dragne, H.; Stoica, D.; Anghel, I.
2018-06-01
The façade fire simulation of buildings is carried out with Pyrosim numerical fire modeling program, following the implementation of a fire scenario in this simulation program. The scenario that was implemented in the Pyrosim program by researchers from the INCERC Fire Safety Research and Testing Laboratory complied with the requirements of BS 8414. The results obtained following the run of the computational program led to the visual validation of effluents at different time points from the beginning of the thermal load burning, as well as the validation in terms of recorded temperatures. It is considered that the results obtained are reasonable, the test being fully validated from the point of view of the implementation of the fire scenario, of the correct development of the effluents and of the temperature values [1].
NASA Technical Reports Server (NTRS)
Gaugler, R. E.
1979-01-01
A computer program to calculate transient and steady state temperatures, pressures, and coolant flows in a cooled axial flow turbine blade or vane with an impingement insert is described. Coolant-side heat transfer coefficients are calculated internally in the program, with the user specifying either impingement or convection heat transfer at each internal flow station. Spent impingement air flows in a chordwise direction and is discharged through the trailing edge and through film cooling holes. The ability of the program to handle film cooling is limited by the internal flow model. Input to the program includes a description of the blade geometry, coolant-supply conditions, outside thermal boundary conditions, and wheel speed. The blade wall can have two layers of different materials, such as a ceramic thermal barrier coating over a metallic substrate. Program output includes the temperature at each node, the coolant pressures and flow rates, and the coolant-side heat transfer coefficients.
Overview of Advanced Turbine Systems Program
NASA Astrophysics Data System (ADS)
Webb, H. A.; Bajura, R. A.
The US Department of Energy initiated a program to develop advanced gas turbine systems to serve both central power and industrial power generation markets. The Advanced Turbine Systems (ATS) Program will lead to commercial offerings by the private sector by 2002. ATS will be developed to fire natural gas but will be adaptable to coal and biomass firing. The systems will be: highly efficient (15 percent improvement over today's best systems); environmentally superior (10 percent reduction in nitrogen oxides over today's best systems); and cost competitive (10 percent reduction in cost of electricity). The ATS Program has five elements. Innovative cycle development will lead to the demonstration of systems with advanced gas turbine cycles using current gas turbine technology. High temperature development will lead to the increased firing temperatures needed to achieve ATS Program efficiency goals. Ceramic component development/demonstration will expand the current DOE/CE program to demonstrate industrial-scale turbines with ceramic components. Technology base will support the overall program by conducting research and development (R&D) on generic technology issues. Coal application studies will adapt technology developed in the ATS program to coal-fired systems being developed in other DOE programs.
Malaria rapid diagnostic tests in tropical climates: the need for a cool chain.
Jorgensen, Pernille; Chanthap, Lon; Rebueno, Antero; Tsuyuoka, Reiko; Bell, David
2006-05-01
Malaria control programs in endemic countries increasingly rely on early case detection and treatment at village level. The rapid diagnostic tests (RDTs) and accompanying drugs on which the success of these programs depends deteriorate to varying degrees at high temperatures. To assess the ability of health systems to maintain RDTs within manufacturers' specifications, we monitored temperatures in the delivery chain from manufacturer through to the village health worker in Cambodia and the Philippines. In both countries, storage temperatures regularly exceeded those recommended for most RDTs intended for field use, whereas temperatures during transport greatly exceeded the lower and upper limits. These results emphasize the need for good logistical planning during the introduction of point-of-care tests in tropical countries and the importance of considering the stability of diagnostic tests during procurement.
[Temperature Measurement with Bluetooth under Android Platform].
Wang, Shuai; Shen, Hao; Luo, Changze
2015-03-01
To realize the real-time transmission of temperature data and display using the platform of intelligent mobile phone and bluetooth. Application of Arduino Uno R3 in temperature data acquisition of digital temperature sensor DS18B20 acquisition, through the HC-05 bluetooth transmits the data to the intelligent smart phone Android system, realizes transmission of temperature data. Using Java language to write applications program under Android development environment, can achieve real-time temperature data display, storage and drawing temperature fluctuations drawn graphics. Temperature sensor is experimentally tested to meet the body temperature measurement precision and accuracy. This paper can provide a reference for other smart phone mobile medical product development.
Boardsailing, How to Establish Your Own Program.
ERIC Educational Resources Information Center
Wiltens, James
1987-01-01
Describes ways to incorporate boardsailing into a camping program. Outlines factors such as size of body of water, wind consistency, water temperature, appropriate supervision/instruction, swim tests, and boards. (LFL)
Fiber-optic temperature probe system for inner body
NASA Astrophysics Data System (ADS)
Liu, Bo; Deng, Xing-Zhong; Cao, Wei; Cheng, Xianping; Xie, Tuqiang; Zhong, Zugen
1991-08-01
The authors have designed a fiber-optic temperature probe system that can quickly insert its probe into bodies to measure temperature. Its thermometer unit has the function of program- controlled zeroing. The single-chip microcomputer is used to control the whole system and process data. The sample system has been tested in a coal furnace.
BURNER RIG TESTING OF A500 C/SiC
2018-03-17
test program characterized the durability behavior of A500® C/SiC ceramic matrix composite material at room and elevated temperature . Specimens were...7 Figure 6. Typical Room- Temperature Tensile Stress-Versus-Strain Trace for As-Manufactured A500...Operation ......................................... 18 Figure 17. Example of the Burner Rig Temperature Profiles Used
Time-dependent deformation of titanium metal matrix composites
NASA Technical Reports Server (NTRS)
Bigelow, C. A.; Bahei-El-din, Y. A.; Mirdamadi, M.
1995-01-01
A three-dimensional finite element program called VISCOPAC was developed and used to conduct a micromechanics analysis of titanium metal matrix composites. The VISCOPAC program uses a modified Eisenberg-Yen thermo-viscoplastic constitutive model to predict matrix behavior under thermomechanical fatigue loading. The analysis incorporated temperature-dependent elastic properties in the fiber and temperature-dependent viscoplastic properties in the matrix. The material model was described and the necessary material constants were determined experimentally. Fiber-matrix interfacial behavior was analyzed using a discrete fiber-matrix model. The thermal residual stresses due to the fabrication cycle were predicted with a failed interface, The failed interface resulted in lower thermal residual stresses in the matrix and fiber. Stresses due to a uniform transverse load were calculated at two temperatures, room temperature and an elevated temperature of 650 C. At both temperatures, a large stress concentration was calculated when the interface had failed. The results indicate the importance of accuracy accounting for fiber-matrix interface failure and the need for a micromechanics-based analytical technique to understand and predict the behavior of titanium metal matrix composites.
Electronic Components and Systems for Cryogenic Space Applications
NASA Technical Reports Server (NTRS)
Patterson, R. L.; Hammoud, A.; Dickman, J. E.; Gerber, S.; Elbuluk, M. E.; Overton, E.
2001-01-01
Electronic components and systems capable of operation at cryogenic temperatures are anticipated in many future NASA space missions such as deep space probes and planetary surface exploration. For example, an unheated interplanetary probe launched to explore the rings of Saturn would reach an average temperature near Saturn of about - 183 C. In addition to surviving the deep space harsh environment, electronics capable of low temperature operation would contribute to improving circuit performance, increasing system efficiency, and reducing payload development and launch costs. Terrestrial applications where components and systems must operate in low temperature environments include cryogenic instrumentation, superconducting magnetic energy storage, magnetic levitation transportation system, and arctic exploration. An on-going research and development program at the NASA Glenn Research Center focuses on the development of reliable electronic devices and efficient power systems capable of surviving in low temperature environments. An overview of the program will be presented in this paper. A description of the low temperature test facilities along with selected data obtained from in-house component testing will also be discussed. Ongoing research activities that are being performed in collaboration with various organizations will also be presented.
Wiese, Steffen; Teutenberg, Thorsten; Schmidt, Torsten C
2012-01-27
In the present work it is shown that the linear elution strength (LES) model which was adapted from temperature-programming gas chromatography (GC) can also be employed for systematic method development in high-temperature liquid chromatography (HT-HPLC). The ability to predict isothermal retention times based on temperature-gradient as well as isothermal input data was investigated. For a small temperature interval of ΔT=40°C, both approaches result in very similar predictions. Average relative errors of predicted retention times of 2.7% and 1.9% were observed for simulations based on isothermal and temperature-gradient measurements, respectively. Concurrently, it was investigated whether the accuracy of retention time predictions of segmented temperature gradients can be further improved by temperature dependent calculation of the parameter S(T) of the LES relationship. It was found that the accuracy of retention time predictions of multi-step temperature gradients can be improved to around 1.5%, if S(T) was also calculated temperature dependent. The adjusted experimental design making use of four temperature-gradient measurements was applied for systematic method development of selected food additives by high-temperature liquid chromatography. Method development was performed within a temperature interval from 40°C to 180°C using water as mobile phase. Two separation methods were established where selected food additives were baseline separated. In addition, a good agreement between simulation and experiment was observed, because an average relative error of predicted retention times of complex segmented temperature gradients less than 5% was observed. Finally, a schedule of recommendations to assist the practitioner during systematic method development in high-temperature liquid chromatography was established. Copyright © 2011 Elsevier B.V. All rights reserved.
High temperature thruster technology for spacecraft propulsion
NASA Technical Reports Server (NTRS)
Schneider, Steven J.
1991-01-01
A technology program intended to develop high-temperature oxidation-resistant thrusters for spacecraft applications is considered. The program will provide the requisite material characterizations and fabrication to incorporate iridium coated rhenium material into small rockets for spacecraft propulsion. This material increases the operating temperature of thrusters to 2200 C, a significant increase over the 1400 C of the silicide-coated niobium chambers currently used. Stationkeeping class 22 N engines fabricated from iridium-coated rhenium have demonstrated steady state specific impulses 20-25 seconds higher than niobium chambers. These improved performances are obtained by reducing or eliminating the fuel film cooling requirements in the combustion chamber while operating at the same overall mixture ratio as conventional engines.
Thundat, Thomas G.; Oden, Patrick I.; Datskos, Panagiotis G.
2000-01-01
A non-contact infrared thermometer measures target temperatures remotely without requiring the ratio of the target size to the target distance to the thermometer. A collection means collects and focusses target IR radiation on an IR detector. The detector measures thermal energy of the target over a spectrum using micromechanical sensors. A processor means calculates the collected thermal energy in at least two different spectral regions using a first algorithm in program form and further calculates the ratio of the thermal energy in the at least two different spectral regions to obtain the target temperature independent of the target size, distance to the target and emissivity using a second algorithm in program form.
High temperature material interactions of thermoelectric systems using silicon germanium.
NASA Technical Reports Server (NTRS)
Stapfer, G.; Truscello, V. C.
1973-01-01
The efficient use of silicon germanium thermoelectric material for radioisotope thermoelectric generators (RTG) is achieved by operation at relatively high temperatures. The insulation technique which is most appropriate for this application uses multiple layers of molybdenum foil and astroquartz. Even so, the long term operation of these materials at elevated temperatures can cause material interaction to occur within the system. To investigate these material interactions, the Jet Propulsion Laboratory is currently testing a number of thermoelectric modules which use four silicon germanium thermoelectric couples in conjunction with the multifoil thermal insulation. The paper discusses the results of the ongoing four-couple module test program and correlates test results with those of a basic material test program.
Fearnot, N E; Kitoh, O; Fujita, T; Okamura, H; Smith, H J; Calderini, M
1989-05-01
The effectiveness of using blood temperature change as an indicator to automatically vary heart rate physiologically was evaluated in 3 patients implanted with Model Sensor Kelvin 500 (Cook Pacemaker Corporation, Leechburg, PA, USA) pacemakers. Each patient performed two block-randomized treadmill exercise tests: one while programmed for temperature-based, rate-modulated pacing and the other while programmed without rate modulation. In 1 pacemaker patient and 4 volunteers, heart rates were recorded during exposure to a hot water bath. Blood temperature measured at 10 sec intervals and pacing rate measured at 1 min intervals were telemetered to a diagnostic programmer and data collector for storage and transfer to a computer. Observation comments and ECG-derived heart rates were manually recorded. The temperature-based pacemaker was shown to respond promptly not only to physical exertion but also to emotionally caused stress and submersion in a hot bath. These events cause increased heart rate in the normal heart. Using a suitable algorithm to process the measurement of blood temperature, it was possible to produce appropriate pacing rates in paced patients.
Computer-Generated Phase Diagrams for Binary Mixtures.
ERIC Educational Resources Information Center
Jolls, Kenneth R.; And Others
1983-01-01
Computer programs that generate projections of thermodynamic phase surfaces through computer graphics were used to produce diagrams representing properties of water and steam and the pressure-volume-temperature behavior of most of the common equations of state. The program, program options emphasizing thermodynamic features of interest, and…
Estimating Arrhenius parameters using temperature programmed molecular dynamics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Imandi, Venkataramana; Chatterjee, Abhijit, E-mail: abhijit@che.iitb.ac.in
2016-07-21
Kinetic rates at different temperatures and the associated Arrhenius parameters, whenever Arrhenius law is obeyed, are efficiently estimated by applying maximum likelihood analysis to waiting times collected using the temperature programmed molecular dynamics method. When transitions involving many activated pathways are available in the dataset, their rates may be calculated using the same collection of waiting times. Arrhenius behaviour is ascertained by comparing rates at the sampled temperatures with ones from the Arrhenius expression. Three prototype systems with corrugated energy landscapes, namely, solvated alanine dipeptide, diffusion at the metal-solvent interphase, and lithium diffusion in silicon, are studied to highlight variousmore » aspects of the method. The method becomes particularly appealing when the Arrhenius parameters can be used to find rates at low temperatures where transitions are rare. Systematic coarse-graining of states can further extend the time scales accessible to the method. Good estimates for the rate parameters are obtained with 500-1000 waiting times.« less
Microcomputer-Aided Control Systems Design.
ERIC Educational Resources Information Center
Roat, S. D.; Melsheimer, S. S.
1987-01-01
Describes a single input/single output feedback control system design program for IBM PC and compatible microcomputers. Uses a heat exchanger temperature control loop to illustrate the various applications of the program. (ML)
GlC analysis of temperature effects on furfural production during pyrolysis of black cherry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barnes D.P.; Blankenhorn, P.R.; Murphey, W.K.
1979-10-01
Thermal degradation of black cherry (Prunus serotina Ehrh.) was conducted in an inert atmosphere at temperatures ranging from 250 degrees to l000 degrees Celcius. The volatiles produced during carbonization were condensed in a liquid nitrogen trap and separated by steam distillation after which they were extracted with ether. This fraction was analyzed by gas-liquid chromatography (GLC) using a 4 mm (inside diameter) by 1.83 m long glass column packed with l0 percent methyl silicone fluid. The (GLC) column temperature was programed from 40 degrees to 240 degrees at a rate of l2.5 degrees Celcius per minute. Using this GLC temperaturemore » program, three chromatograms from each carbonization temperature were obtained and the furfural peak was identified and quantitatively analyzed. As carbonization temperature increased from 250 degrees at 500 degrees Celcius, the amount of furfural in the condensate also increased. The condensate chromatograms show that considerably more compounds are formed at temperatures above 320 degrees Celcius. The chromatograms from the temperature range of 500 degrees to l000 degrees showed little change in the number of compounds detected. Regression analysis revealed relationships between carbonization temperature, mass of the condensate, and mass furfural per original mass of wood.« less
Delaney, P.T.
1988-01-01
Temperature histories obtained from transient heat-conduction theory are applicable to most dikes despite potential complicating effects related to magma flow during emplacement, groundwater circulation, and metamorphic reaction during cooling. Here. machine-independent FORTRAN 77 programs are presented to calculate temperatures in and around dikes as they cool conductively. Analytical solutions can treat thermal-property contrasts between the dike and host rocks, but cannot address the release of magmatic heat of crystallization after the early stages of cooling or the appreciable temperature dependence of thermal conductivity and diffusivity displayed by most rock types. Numerical solutions can incorporate these additional factors. The heat of crystallization can raise the initial temperature at the dike contact, ??c1, about 100??C above that which would be estimated if it were neglected, and can decrease the rate at which the front of solidified magma moves to the dike center by a factor of as much as three. Thermal conductivity and diffusivity of rocks increase with decreasing temperature and, at low temperatures, these properties increase more if the rocks are saturated with water. Models that treat these temperature dependencies yield estimates of ??c1 that are as much as 75??C beneath those which would be predicted if they were neglected. ?? 1988.
Metals and Ceramics Division progress report for period ending December 31, 1992
DOE Office of Scientific and Technical Information (OSTI.GOV)
Craig, D.F.; Weir, J.R. Jr.
1993-04-01
This report provides a brief overview of the activities and accomplishments of the division, whose purpose is to provide technical support, primarily in the area of high-temperature materials, for the various technologies being developed by US DOE. Activities range from basic research to industrial research and technology transfer. The division (and the report) is divided into the following: Engineering materials, high-temperature materials, materials science, ceramics, nuclear fuel materials, program activities, collaborative research facilities and technology transfer, and educational programs.
Single-node orbit analsyis with radiation heat transfer only
NASA Technical Reports Server (NTRS)
Peoples, J. A.
1977-01-01
The steady-state temperature of a single node which dissipates energy by radiation only is discussed for a nontime varying thermal environment. Relationships are developed to illustrate how shields can be utilized to represent a louver system. A computer program is presented which can assess periodic temperature characteristics of a single node in a time varying thermal environment having energy dissipation by radiation only. The computer program performs thermal orbital analysis for five combinations of plate, shields, and louvers.
Cooperative implementation of a high temperature acoustic sensor
NASA Technical Reports Server (NTRS)
Baldini, S. E.; Nowakowski, Edward; Smith, Herbert G.; Friebele, E. J.; Putnam, Martin A.; Rogowski, Robert; Melvin, Leland D.; Claus, Richard O.; Tran, Tuan; Holben, Milford S., Jr.
1991-01-01
The current status and results of a cooperative program aimed at the implementation of a high-temperature acoustic/strain sensor onto metallic structures are reported. The sensor systems that are to be implemented under this program will measure thermal expansion, maneuver loads, aircraft buffet, sonic fatigue, and acoustic emissions in environments that approach 1800 F. The discussion covers fiber development, fabrication of an extrinsic Fabry-Perot interferometer acoustic sensor, sensor mounting/integration, and results of an evaluation of the sensor capabilities.
Simplified liquid oxygen propellant conditioning concepts
NASA Technical Reports Server (NTRS)
Cleary, N. L.; Holt, K. A.; Flachbart, R. H.
1995-01-01
Current liquid oxygen feed systems waste propellant and use hardware, unnecessary during flight, to condition the propellant at the engine turbopumps prior to launch. Simplified liquid oxygen propellant conditioning concepts are being sought for future launch vehicles. During a joint program, four alternative propellant conditioning options were studied: (1) passive recirculation; (2) low bleed through the engine; (3) recirculation lines; and (4) helium bubbling. The test configuration for this program was based on a vehicle design which used a main recirculation loop that was insulated on the downcomer and uninsulated on the upcomer. This produces a natural convection recirculation flow. The test article for this program simulated a feedline which ran from the main recirculation loop to the turbopump. The objective was to measure the temperature profile of this test article. Several parameters were varied from the baseline case to determine their effects on the temperature profile. These parameters included: flow configuration, feedline slope, heat flux, main recirculation loop velocity, pressure, bleed rate, helium bubbling, and recirculation lines. The heat flux, bleed rate, and recirculation configurations produced the greatest changes from the baseline temperature profile. However, the temperatures in the feedline remained subcooled. Any of the options studied could be used in future vehicles.
Definition study for temperature control in advanced protein crystal growth
NASA Technical Reports Server (NTRS)
Nyce, Thomas A.; Rosenberger, Franz; Sowers, Jennifer W.; Monaco, Lisa A.
1990-01-01
Some of the technical requirements for an expedient application of temperature control to advanced protein crystal growth activities are defined. Lysozome was used to study the effects of temperature ramping and temperature gradients for nucleation/dissolution and consecutive growth of sizable crystals and, to determine a prototype temperature program. The solubility study was conducted using equine serum albumin (ESA) which is an extremely stable, clinically important protein due to its capability to bind and transport many different small ions and molecules.
Computer program documentation: CYBER to Univac binary conversion user's guide
NASA Technical Reports Server (NTRS)
Martin, E. W.
1980-01-01
A user's guide for a computer program which will convert SINDA temperature history data from CDC (Cyber) binary format to UNIVAC 1100 binary format is presented. The various options available, the required input, the optional output, file assignments, and the restrictions of the program are discussed.
Learning Programming through Baking
ERIC Educational Resources Information Center
Moon, Cameron
2018-01-01
Baking a cake and programming have many attributes in common. Both baking and programming rely on a specific process to produce an expected outcome. A cake needs the right amount of each ingredient mixed in at the right time, the oven to be set at a specific temperature, and the cake to be baked for a specific length of time. Programs need to be…
NASA Astrophysics Data System (ADS)
Predoi-Cross, Adriana; Liu, W.; Murphy, Reba; Povey, Chad; Gamache, R.; Laraia, A.; McKellar, A. R. W.; Hurtmans, Daniel; Devi, V. M.
2015-10-01
The group of authors would like to make the following clarification: the retrievals of self-broadened temperature dependence coefficients were performed by the authors both using the multispectrum fit program from Ref. [14] and using the multispectrum fit program of D. Chris Benner [Benner DC, Rinsland CP, Devi VM, Smith MAH, Atkins D. A multispectrum nonlinear least-squares fitting technique. J. Quant. Spectrosc. Radiat. Transf. 1995;53:705-21.). To retrieve the room temperature self-broadening parameters, the authors have used the values in Ref. [4]. For reasons of consistency with the results published for air-broadening and air-shift temperature dependence coefficients in A. Predoi-Cross, A.R.W. McKellar, D. Chris Benner, V. Malathy Devi, R.R. Gamache, C.E. Miller, R.A. Toth, L.R. Brown, Temperature dependences for air-broadened Lorentz half width and pressure-shift coefficients in the 30013←00001 and 30012←00001 bands of CO2near 1600 μm, Canadian Journal of Physics, 87 (5) (2009) 517-535, Tables 2 and 3, and Figures 2 and 4 contain only the values retrieved using the multispectrum fit program of D. Chris Benner. We would like to thank D. Chris Benner for allowing us to use his fitting software.
NASA Astrophysics Data System (ADS)
Bakker, Ronald J.
2018-06-01
The program AqSo_NaCl has been developed to calculate pressure - molar volume - temperature - composition (p-V-T-x) properties, enthalpy, and heat capacity of the binary H2O-NaCl system. The algorithms are designed in BASIC within the Xojo programming environment, and can be operated as stand-alone project with Macintosh-, Windows-, and Unix-based operating systems. A series of ten self-instructive interfaces (modules) are developed to calculate fluid inclusion properties and pore fluid properties. The modules may be used to calculate properties of pure NaCl, the halite-liquidus, the halite-vapourus, dew-point and bubble-point curves (liquid-vapour), critical point, and SLV solid-liquid-vapour curves at temperatures above 0.1 °C (with halite) and below 0.1 °C (with ice or hydrohalite). Isochores of homogeneous fluids and unmixed fluids in a closed system can be calculated and exported to a.txt file. Isochores calculated for fluid inclusions can be corrected according to the volumetric properties of quartz. Microthermometric data, i.e. dissolution temperatures and homogenization temperatures, can be used to calculated bulk fluid properties of fluid inclusions. Alternatively, in the absence of total homogenization temperature the volume fraction of the liquid phase in fluid inclusions can be used to obtain bulk properties.
NASA Technical Reports Server (NTRS)
Johns, Albert L.; Neiner, George; Bencic, Timothy J.; Flood, Joseph D.; Amuedo, Kurt C.
1990-01-01
A 9.2 percent scale STOVL hot gas ingestion model was tested in the NASA Lewis 9 x 15-foot Low-Speed Wind Tunnel. Flow visualization from the Phase 1 test program, which evaluated the hot ingestion phenomena and control techniques, is covered. The Phase 2 test program evaluated the hot gas ingestion phenomena at higher temperatures and used a laser sheet to investigate the flow field. Hot gas ingestion levels were measured for the several forward nozzle splay configurations and with flow control/life improvement devices (LIDs) which reduced the hot gas ingestion. The test was conducted at full scale nozzle pressure ratios and inlet Mach numbers. Results are presented over a range of nozzle pressure ratios at a 10 kn headwind velocity. The Phase 2 program was conducted at exhaust nozzle temperatures up to 1460 R and utilized a sheet laser system for flow visualization of the model flow field in and out of ground effects. The results reported are for nozzle exhaust temperatures up to 1160 R and contain the compressor face pressure and temperature distortions, the total pressure recovery, the inlet temperature rise, and the environmental effects of the hot gas. The environmental effects include the ground plane contours, the model airframe heating, and the location of the ground flow separation.
Development of an ultra-high temperature infrared scene projector at Santa Barbara Infrared Inc.
NASA Astrophysics Data System (ADS)
Franks, Greg; Laveigne, Joe; Danielson, Tom; McHugh, Steve; Lannon, John; Goodwin, Scott
2015-05-01
The rapid development of very-large format infrared detector arrays has challenged the IR scene projector community to develop correspondingly larger-format infrared emitter arrays to support the testing needs of systems incorporating these detectors. As with most integrated circuits, fabrication yields for the read-in integrated circuit (RIIC) that drives the emitter pixel array are expected to drop dramatically with increasing size, making monolithic RIICs larger than the current 1024x1024 format impractical and unaffordable. Additionally, many scene projector users require much higher simulated temperatures than current technology can generate to fully evaluate the performance of their systems and associated processing algorithms. Under the Ultra High Temperature (UHT) development program, Santa Barbara Infrared Inc. (SBIR) is developing a new infrared scene projector architecture capable of producing both very large format (>1024x1024) resistive emitter arrays and improved emitter pixel technology capable of simulating very high apparent temperatures. During an earlier phase of the program, SBIR demonstrated materials with MWIR apparent temperatures in excess of 1000K. New emitter materials have subsequently been selected to produce pixels that achieve even higher apparent temperatures. Test results from pixels fabricated using the new material set will be presented and discussed. Also in development under the same UHT program is a 'scalable' RIIC that will be used to drive the high temperature pixels. This RIIC will utilize through-silicon vias (TSVs) and quilt packaging (QP) technologies to allow seamless tiling of multiple chips to fabricate very large arrays, and thus overcome the inherent yield limitations of very-large-scale integrated circuits. Current status of the RIIC development effort will also be presented.
Modeling the glass transition of amorphous networks for shape-memory behavior
NASA Astrophysics Data System (ADS)
Xiao, Rui; Choi, Jinwoo; Lakhera, Nishant; Yakacki, Christopher M.; Frick, Carl P.; Nguyen, Thao D.
2013-07-01
In this paper, a thermomechanical constitutive model was developed for the time-dependent behaviors of the glass transition of amorphous networks. The model used multiple discrete relaxation processes to describe the distribution of relaxation times for stress relaxation, structural relaxation, and stress-activated viscous flow. A non-equilibrium thermodynamic framework based on the fictive temperature was introduced to demonstrate the thermodynamic consistency of the constitutive theory. Experimental and theoretical methods were developed to determine the parameters describing the distribution of stress and structural relaxation times and the dependence of the relaxation times on temperature, structure, and driving stress. The model was applied to study the effects of deformation temperatures and physical aging on the shape-memory behavior of amorphous networks. The model was able to reproduce important features of the partially constrained recovery response observed in experiments. Specifically, the model demonstrated a strain-recovery overshoot for cases programmed below Tg and subjected to a constant mechanical load. This phenomenon was not observed for materials programmed above Tg. Physical aging, in which the material was annealed for an extended period of time below Tg, shifted the activation of strain recovery to higher temperatures and increased significantly the initial recovery rate. For fixed-strain recovery, the model showed a larger overshoot in the stress response for cases programmed below Tg, which was consistent with previous experimental observations. Altogether, this work demonstrates how an understanding of the time-dependent behaviors of the glass transition can be used to tailor the temperature and deformation history of the shape-memory programming process to achieve more complex shape recovery pathways, faster recovery responses, and larger activation stresses.
Automatic control of finite element models for temperature-controlled radiofrequency ablation
Haemmerich, Dieter; Webster, John G
2005-01-01
Background The finite element method (FEM) has been used to simulate cardiac and hepatic radiofrequency (RF) ablation. The FEM allows modeling of complex geometries that cannot be solved by analytical methods or finite difference models. In both hepatic and cardiac RF ablation a common control mode is temperature-controlled mode. Commercial FEM packages don't support automating temperature control. Most researchers manually control the applied power by trial and error to keep the tip temperature of the electrodes constant. Methods We implemented a PI controller in a control program written in C++. The program checks the tip temperature after each step and controls the applied voltage to keep temperature constant. We created a closed loop system consisting of a FEM model and the software controlling the applied voltage. The control parameters for the controller were optimized using a closed loop system simulation. Results We present results of a temperature controlled 3-D FEM model of a RITA model 30 electrode. The control software effectively controlled applied voltage in the FEM model to obtain, and keep electrodes at target temperature of 100°C. The closed loop system simulation output closely correlated with the FEM model, and allowed us to optimize control parameters. Discussion The closed loop control of the FEM model allowed us to implement temperature controlled RF ablation with minimal user input. PMID:16018811
TAP 2: A finite element program for thermal analysis of convectively cooled structures
NASA Technical Reports Server (NTRS)
Thornton, E. A.
1980-01-01
A finite element computer program (TAP 2) for steady-state and transient thermal analyses of convectively cooled structures is presented. The program has a finite element library of six elements: two conduction/convection elements to model heat transfer in a solid, two convection elements to model heat transfer in a fluid, and two integrated conduction/convection elements to represent combined heat transfer in tubular and plate/fin fluid passages. Nonlinear thermal analysis due to temperature-dependent thermal parameters is performed using the Newton-Raphson iteration method. Transient analyses are performed using an implicit Crank-Nicolson time integration scheme with consistent or lumped capacitance matrices as an option. Program output includes nodal temperatures and element heat fluxes. Pressure drops in fluid passages may be computed as an option. User instructions and sample problems are presented in appendixes.
Constitutive modeling for isotropic materials
NASA Technical Reports Server (NTRS)
Chan, K. S.; Lindholm, U. S.; Bodner, S. R.
1988-01-01
The third and fourth years of a 4-year research program, part of the NASA HOST Program, are described. The program goals were: (1) to develop and validate unified constitutive models for isotropic materials, and (2) to demonstrate their usefulness for structural analysis of hot section components of gas turbine engines. The unified models selected for development and evaluation were those of Bodner-Partom and of Walker. The unified approach for elastic-viscoplastic constitutive equations is a viable method for representing and predicting material response characteristics in the range where strain rate and temperature dependent inelastic deformations are experienced. This conclusion is reached by extensive comparison of model calculations against the experimental results of a test program of two high temperature Ni-base alloys, B1900+Hf and Mar-M247, over a wide temperature range for a variety of deformation and thermal histories including uniaxial, multiaxial, and thermomechanical loading paths. The applicability of the Bodner-Partom and the Walker models for structural applications has been demonstrated by implementing these models into the MARC finite element code and by performing a number of analyses including thermomechanical histories on components of hot sections of gas turbine engines and benchmark notch tensile specimens. The results of the 4-year program have been published in four annual reports. The results of the base program are summarized in this report. The tasks covered include: (1) development of material test procedures, (2) thermal history effects, and (3) verification of the constitutive model for an alternative material.
NASA Technical Reports Server (NTRS)
Smith, E. K.; Waters, J. W.
1981-01-01
A sophisticated but flexible radiative transfer program designed to assure internal consistency was used to produce brightness temperature (sky noise temperature in a given direction) and gaseous attenuation curves. The curves, derived from atmospheric models, were compared and a new set was derived for a specified frequency range.
NECAP: NASA's Energy-Cost Analysis Program. Part 1: User's manual
NASA Technical Reports Server (NTRS)
Henninger, R. H. (Editor)
1975-01-01
The NECAP is a sophisticated building design and energy analysis tool which has embodied within it all of the latest ASHRAE state-of-the-art techniques for performing thermal load calculation and energy usage predictions. It is a set of six individual computer programs which include: response factor program, data verification program, thermal load analysis program, variable temperature program, system and equipment simulation program, and owning and operating cost program. Each segment of NECAP is described, and instructions are set forth for preparing the required input data and for interpreting the resulting reports.
Computer assisted screening, correction, and analysis of historical weather measurements
NASA Astrophysics Data System (ADS)
Burnette, Dorian J.; Stahle, David W.
2013-04-01
A computer program, Historical Observation Tools (HOB Tools), has been developed to facilitate many of the calculations used by historical climatologists to develop instrumental and documentary temperature and precipitation datasets and makes them readily accessible to other researchers. The primitive methodology used by the early weather observers makes the application of standard techniques difficult. HOB Tools provides a step-by-step framework to visually and statistically assess, adjust, and reconstruct historical temperature and precipitation datasets. These routines include the ability to check for undocumented discontinuities, adjust temperature data for poor thermometer exposures and diurnal averaging, and assess and adjust daily precipitation data for undercount. This paper provides an overview of the Visual Basic.NET program and a demonstration of how it can assist in the development of extended temperature and precipitation datasets using modern and early instrumental measurements from the United States.
Development open source microcontroller based temperature data logger
NASA Astrophysics Data System (ADS)
Abdullah, M. H.; Che Ghani, S. A.; Zaulkafilai, Z.; Tajuddin, S. N.
2017-10-01
This article discusses the development stages in designing, prototyping, testing and deploying a portable open source microcontroller based temperature data logger for use in rough industrial environment. The 5V powered prototype of data logger is equipped with open source Arduino microcontroller for integrating multiple thermocouple sensors with their module, secure digital (SD) card storage, liquid crystal display (LCD), real time clock and electronic enclosure made of acrylic. The program for the function of the datalogger is programmed so that 8 readings from the thermocouples can be acquired within 3 s interval and displayed on the LCD simultaneously. The recorded temperature readings at four different points on both hydrodistillation show similar profile pattern and highest yield of extracted oil was achieved on hydrodistillation 2 at 0.004%. From the obtained results, this study achieved the objective of developing an inexpensive, portable and robust eight channels temperature measuring module with capabilities to monitor and store real time data.
Flight contaminant trace analyser. Phase 1: Chromatographic input system
NASA Technical Reports Server (NTRS)
1975-01-01
The development of a chromatographic column capable of resolving compounds associated with spacecraft atmospheres is presented. Consideration is given to sampling techniques, column parameters and operation, and column interface with a mass spectrometer. A capillary column coated with a mixture of polyalkylene glycols is found to provide the best selectivity for resolving multicomponent mixtures found in spacecraft atmospheres. Temperature programming and isothermal operation of the column are evaluated and it is found that temperature programming has a shorter analysis time for a given carrier gas flow rate and overall superior resolution. It is observed that hydrogen provides a 15% savings in analysis time over helium. Following the optimization of column operational parameters, a mixed phase Ucon capillary is prepared for evaluation during the column test period in which the test sample is automatically analyzed. Analysis of the multicomponent test mixture is completed within 45 minutes provided temperature programming is used. All but two of the test compounds are well resolved.
Aerothermal Test of Thermal Protection Systems for X-33 Reusable Launch Vehicle
NASA Technical Reports Server (NTRS)
Sawyer, James Wayne; Hodge, Jefferson; Moore, Brad; Snyder, Kevin
1999-01-01
An array of metallic Thermal Protection System (TPS) panels developed for the windward surface of the X-33 vehicle was tested in the 8-Foot High Temperature Tunnel at the NASA Langley Research Center. These tests were the first aerothermal tests of an X-33 TPS array and the test results will be used to validate the TPS for the X-33 flight program. Specifically, the tests evaluated the structural and thermal performance of the TPS, the effectiveness of the high temperature seals between adjacent panels and the durability of the TPS under realistic aerothermal flight conditions. The effect of varying panel-to-panel step heights, intentional damage to the seals between adjacent panels, and the use of secondary seals were also investigated during the test program. The metallic TPS developed for the windward surface of the X-33, the blanket TPS developed to protect the leeward surfaces of the X-33, and the test program in the 8-Foot High Temperature Tunnel are presented and discussed.
FY16 ASME High Temperature Code Activities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swindeman, M. J.; Jetter, R. I.; Sham, T. -L.
2016-09-01
One of the objectives of the ASME high temperature Code activities is to develop and validate both improvements and the basic features of Section III, Division 5, Subsection HB, Subpart B (HBB). The overall scope of this task is to develop a computer program to be used to assess whether or not a specific component under specified loading conditions will satisfy the elevated temperature design requirements for Class A components in Section III, Division 5, Subsection HB, Subpart B (HBB). There are many features and alternative paths of varying complexity in HBB. The initial focus of this task is amore » basic path through the various options for a single reference material, 316H stainless steel. However, the program will be structured for eventual incorporation all the features and permitted materials of HBB. Since this task has recently been initiated, this report focuses on the description of the initial path forward and an overall description of the approach to computer program development.« less
Comparison of two procedures for predicting rocket engine nozzle performance
NASA Technical Reports Server (NTRS)
Davidian, Kenneth J.
1987-01-01
Two nozzle performance prediction procedures which are based on the standardized JANNAF methodology are presented and compared for four rocket engine nozzles. The first procedure required operator intercedence to transfer data between the individual performance programs. The second procedure is more automated in that all necessary programs are collected into a single computer code, thereby eliminating the need for data reformatting. Results from both procedures show similar trends but quantitative differences. Agreement was best in the predictions of specific impulse and local skin friction coefficient. Other compared quantities include characteristic velocity, thrust coefficient, thrust decrement, boundary layer displacement thickness, momentum thickness, and heat loss rate to the wall. Effects of wall temperature profile used as an input to the programs was investigated by running three wall temperature profiles. It was found that this change greatly affected the boundary layer displacement thickness and heat loss to the wall. The other quantities, however, were not drastically affected by the wall temperature profile change.
Thermal-mechanical fatigue behavior of nickel-base superalloys
NASA Technical Reports Server (NTRS)
Pelloux, R. M.; Marchand, N.
1986-01-01
The main achievements of a 36-month research program are presented. The main objective was to gain more insight into the problem of crack growth under thermal mechanical fatigue (TMF) conditions. This program was conducted at M.I.T. for the period of September 1982 to September 1985. The program was arranged into five technical tasks. Under Task I, the literature of TMF data was reviewed. The goal was to identify the crack propagation conditions in aircraft engines (hot section) and to assess the validity of conventional fracture mechanics parameters to address TMF crack growth. The second task defined the test facilities, test specimen and the testing conditions needed to establish the effectiveness of data correlation parameters identified in Task I. Three materials (Inconel X-750, Hastelloy-X, and B-1900) were chosen for the program. Task II was accomplished in collaboration with Pratt & Whitney Aircraft engineers. Under Task III, a computerized testing system to measure the TMF behavior (LCF and CG behaviors) of various alloys systems was built. The software used to run isothermal and TMF tests was also developed. Built around a conventional servohydraulic machine, the system is capable of push-pull tests under stress or strain and temperature controlled conditions in the temperature range of 25C to 1050C. A crack propagation test program was defined and conducted under Task IV. The test variables included strain range, strain rate (frequency) and temperature. Task V correlated and generalized the Task IV data for isothermal and variable temperature conditions so that several crack propagation parameters could be compared and evaluated. The structural damage (mode of cracking and dislocation substructure) under TMF cycling was identified and contrasted with the isothermal damage to achieve a sound fundamental mechanistic understanding of TMF.
NASA Technical Reports Server (NTRS)
Gabb, Tim; Gayda, John; Telesman, Jack
2001-01-01
The advanced powder metallurgy disk alloy ME3 was designed using statistical screening and optimization of composition and processing variables in the NASA HSR/EPM disk program to have extended durability at 1150 to 1250 "Fin large disks. Scaled-up disks of this alloy were produced at the conclusion of this program to demonstrate these properties in realistic disk shapes. The objective of the UEET disk program was to assess the mechanical properties of these ME3 disks as functions of temperature, in order to estimate the maximum temperature capabilities of this advanced alloy. Scaled-up disks processed in the HSR/EPM Compressor / Turbine Disk program were sectioned, machined into specimens, and tested in tensile, creep, fatigue, and fatigue crack growth tests by NASA Glenn Research Center, in cooperation with General Electric Engine Company and Pratt & Whitney Aircraft Engines. Additional sub-scale disks and blanks were processed and tested to explore the effects of several processing variations on mechanical properties. Scaled-up disks of an advanced regional disk alloy, Alloy 10, were used to evaluate dual microstructure heat treatments. This allowed demonstration of an improved balance of properties in disks with higher strength and fatigue resistance in the bores and higher creep and dwell fatigue crack growth resistance in the rims. Results indicate the baseline ME3 alloy and process has 1300 to 1350 O F temperature capabilities, dependent on detailed disk and engine design property requirements. Chemistry and process enhancements show promise for further increasing temperature capabilities.
Computer Programs for Calculating the Isentropic Flow Properties for Mixtures of R-134a and Air
NASA Technical Reports Server (NTRS)
Kvaternik, Raymond G.
2000-01-01
Three computer programs for calculating the isentropic flow properties of R-134a/air mixtures which were developed in support of the heavy gas conversion of the Langley Transonic Dynamics Tunnel (TDT) from dichlorodifluoromethane (R-12) to 1,1,1,2 tetrafluoroethane (R-134a) are described. The first program calculates the Mach number and the corresponding flow properties when the total temperature, total pressure, static pressure, and mole fraction of R-134a in the mixture are given. The second program calculates tables of isentropic flow properties for a specified set of free-stream Mach numbers given the total pressure, total temperature, and mole fraction of R-134a. Real-gas effects are accounted for in these programs by treating the gases comprising the mixture as both thermally and calorically imperfect. The third program is a specialized version of the first program in which the gases are thermally perfect. It was written to provide a simpler computational alternative to the first program in those cases where real-gas effects are not important. The theory and computational procedures underlying the programs are summarized, the equations used to compute the flow quantities of interest are given, and sample calculated results that encompass the operating conditions of the TDT are shown.
The Development of a Fiber Optic Raman Temperature Measurement System for Rocket Flows
NASA Technical Reports Server (NTRS)
Degroot, Wim A.
1992-01-01
A fiberoptic Raman diagnostic system for H2/O2 rocket flows is currently under development. This system is designed for measurement of temperature and major species concentration in the combustion chamber and part of the nozzle of a 100 Newton thrust rocket currently undergoing testing. This paper describes a measurement system based on the spontaneous Raman scattering phenomenon. An analysis of the principles behind the technique is given. Software is developed to measure temperature and major species concentrations by comparing theoretical Raman scattering spectra with experimentally obtained spectra. Equipment selection and experimental approach are summarized. This experimental program is part of a program, which is in progress, to evaluate Navier-Stokes based analyses for this class of rocket.
Prediction of Layer Thickness in Molten Borax Bath with Genetic Evolutionary Programming
NASA Astrophysics Data System (ADS)
Taylan, Fatih
2011-04-01
In this study, the vanadium carbide coating in molten borax bath process is modeled by evolutionary genetic programming (GEP) with bath composition (borax percentage, ferro vanadium (Fe-V) percentage, boric acid percentage), bath temperature, immersion time, and layer thickness data. Five inputs and one output data exist in the model. The percentage of borax, Fe-V, and boric acid, temperature, and immersion time parameters are used as input data and the layer thickness value is used as output data. For selected bath components, immersion time, and temperature variables, the layer thicknesses are derived from the mathematical expression. The results of the mathematical expressions are compared to that of experimental data; it is determined that the derived mathematical expression has an accuracy of 89%.
Estimating vapor pressures of pure liquids
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haraburda, S.S.
1996-03-01
Calculating the vapor pressures for pure liquid chemicals is a key step in designing equipment for separation of liquid mixtures. Here is a useful way to develop an equation for predicting vapor pressures over a range of temperatures. The technique uses known vapor pressure points for different temperatures. Although a vapor-pressure equation is being showcased in this article, the basic method has much broader applicability -- in fact, users can apply it to develop equations for any temperature-dependent model. The method can be easily adapted for use in software programs for mathematics evaluation, minimizing the need for any programming. Themore » model used is the Antoine equation, which typically provides a good correlation with experimental or measured data.« less
Elevated temperature crack growth
NASA Technical Reports Server (NTRS)
Malik, S. N.; Vanstone, R. H.; Kim, K. S.; Laflen, J. H.
1985-01-01
The purpose is to determine the ability of currently available P-I integrals to correlate fatigue crack propagation under conditions that simulate the turbojet engine combustor liner environment. The utility of advanced fracture mechanics measurements will also be evaluated during the course of the program. To date, an appropriate specimen design, a crack displacement measurement method, and boundary condition simulation in the computational model of the specimen were achieved. Alloy 718 was selected as an analog material based on its ability to simulate high temperature behavior at lower temperatures. Tensile and cyclic tests were run at several strain rates so that an appropriate constitutive model could be developed. Suitable P-I integrals were programmed into a finite element post-processor for eventual comparison with experimental data.
Bridge response due to temperature variations.
DOT National Transportation Integrated Search
2014-05-01
In order to more accurately quantify the behavior and degradation of bridges throughout their service life, the : Federal Highway Administration lunched the Long-Term Bridge Performance Program. As part of this program : an I-girder, integral abutmen...
Multicolor pyrometer for materials processing in space, phase 2
NASA Technical Reports Server (NTRS)
Frish, Michael; Frank, Jonathan; Beerman, Henry
1988-01-01
The program goals were to design, construct, and program a prototype passive imaging pyrometer capable of measuring, as accurately as possible, the temperature distribution across the surface of a moving object suspended in space.
Diode step stress testing program for JANTX1N5550
NASA Technical Reports Server (NTRS)
1979-01-01
The effect was studied of power/temperature step stress when applied to the switching diode JANTX1N5550 manufactured by Semtech and Micro Semiconductor. The power/temperature stress tests are presented, and failure analyses are included.
NASA Technical Reports Server (NTRS)
Mccarty, R. D.
1980-01-01
The thermodynamic and transport properties of selected cryogens had programmed into a series of computer routines. Input variables are any two of P, rho or T in the single phase regions and either P or T for the saturated liquid or vapor state. The output is pressure, density, temperature, entropy, enthalpy for all of the fluids and in most cases specific heat capacity and speed of sound. Viscosity and thermal conductivity are also given for most of the fluids. The programs are designed for access by remote terminal; however, they have been written in a modular form to allow the user to select either specific fluids or specific properties for particular needs. The program includes properties for hydrogen, helium, neon, nitrogen, oxygen, argon, and methane. The programs include properties for gaseous and liquid states usually from the triple point to some upper limit of pressure and temperature which varies from fluid to fluid.
NASA Technical Reports Server (NTRS)
Saltsman, James F.
1992-01-01
This manual presents computer programs for characterizing and predicting fatigue and creep-fatigue resistance of metallic materials in the high-temperature, long-life regime for isothermal and nonisothermal fatigue. The programs use the total strain version of Strainrange Partitioning (TS-SRP). An extensive database has also been developed in a parallel effort. This database is probably the largest source of high-temperature, creep-fatigue test data available in the public domain and can be used with other life prediction methods as well. This users manual, software, and database are all in the public domain and are available through COSMIC (382 East Broad Street, Athens, GA 30602; (404) 542-3265, FAX (404) 542-4807). Two disks accompany this manual. The first disk contains the source code, executable files, and sample output from these programs. The second disk contains the creep-fatigue data in a format compatible with these programs.
NASA Technical Reports Server (NTRS)
Jaffe, L. D.
1984-01-01
The CONC/11 computer program designed for calculating the performance of dish-type solar thermal collectors and power systems is discussed. This program is intended to aid the system or collector designer in evaluating the performance to be expected with possible design alternatives. From design or test data on the characteristics of the various subsystems, CONC/11 calculates the efficiencies of the collector and the overall power system as functions of the receiver temperature for a specified insolation. If desired, CONC/11 will also determine the receiver aperture and the receiver temperature that will provide the highest efficiencies at a given insolation. The program handles both simple and compound concentrators. The CONC/11 is written in Athena Extended FORTRAN (similar to FORTRAN 77) to operate primarily in an interactive mode on a Sperry 1100/81 computer. It could also be used on many small computers. A user's manual is also provided for this program.
NASA Technical Reports Server (NTRS)
Viswanathan, A. V.; Tamekuni, M.; Tripp, L. L.
1974-01-01
General-purpose program is intended for thermal stress and instability analyses of structures such as axially-stiffened curved panels. Two types of instability analyses can be effected by program: (1) thermal buckling with temperature variation as specified and (2) buckling due to in-plane biaxial loading.
NASA Technical Reports Server (NTRS)
Gaugler, R. E.
1978-01-01
A computer program to calculate transient and steady state temperatures, pressures, and coolant flows in a cooled, axial flow turbine blade or vane with an impingement insert is described. Coolant side heat transfer coefficients are calculated internally in the program, with the user specifying either impingement or convection heat transfer at each internal flow station. Spent impingement air flows in a chordwise direction and is discharged through the trailing edge and through film cooling holes. The ability of the program to handle film cooling is limited by the internal flow model. Sample problems, with tables of input and output, are included in the report. Input to the program includes a description of the blade geometry, coolant supply conditions, outside thermal boundary conditions, and wheel speed. The blade wall can have two layers of different materials, such as a ceramic thermal barrier coating over a metallic substrate. Program output includes the temperature at each node, the coolant pressures and flow rates, and the inside heat-transfer coefficients.
Plant cover, soil temperature, freeze, water stress, and evapotranspiration conditions. [south Texas
NASA Technical Reports Server (NTRS)
Wiegand, C. L.; Nixon, P. R.; Gausman, H. W.; Namken, L. N.; Leamer, R. W.; Richardson, A. J. (Principal Investigator)
1981-01-01
Emissive and reflective data for 10 days, and IR data for 6 nights in south Texas scenes were analyzed after procedures were developed for removing cloud-affected data. HCMM radiometric temperatures were: within 2 C of dewpoint temperatures on nights when air temperature approached dewpoint temperatures; significantly correlated with variables important in evapotranspiration; and, related to freeze severity and planting depth soil temperatures. Vegetation greenness indexes calculated from visible and reflective IR bands of NOAA-6 to -9 meteorological satellites will be useful in the AgRISTARS program for seasonal crop development, crop condition, and drought applications.
Sustained Low Temperature NOx Reduction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zha, Yuhui
Increasing regulatory, environmental, and customer pressure in recent years led to substantial improvements in the fuel efficiency of diesel engines, including the remarkable breakthroughs demonstrated through the Super Truck program supported by the U.S. Department of Energy (DOE). On the other hand, these improvements have translated into a reduction of exhaust gas temperatures, thus further complicating the task of controlling NOx emissions, especially in low power duty cycles. The need for improved NOx conversion over these low temperature duty cycles is also observed as requirements tighten with in-use emissions testing. Sustained NOx reduction at low temperatures, especially in the 150-200oCmore » range, shares some similarities with the more commonly discussed cold-start challenge, however poses a number of additional and distinct technical problems. In this project we set a bold target of achieving and maintaining a 90% NOx conversion at the SCR catalyst inlet temperature of 150oC. The project is intended to push the boundaries of the existing technologies, while staying within the realm of realistic future practical implementation. In order to meet the resulting challenges at the levels of catalyst fundamentals, system components, and system integration, Cummins has partnered with the DOE, Johnson Matthey, and Pacific Northwest National Lab and initiated the Sustained Low-Temperature NOx Reduction program at the beginning of 2015. Through this collaboration, we are exploring catalyst formulations and catalyst architectures with enhanced catalytic activity at 150°C; opportunities to approach the desirable ratio of NO and NO2 in the SCR feed gas; options for robust low-temperature reductant delivery; and the requirements for overall system integration. The program is expected to deliver an on-engine demonstration of the technical solution and an assessment of its commercial potential. In the SAE meeting, we will share the initial performance data on engine to highlight the path to achieve 90% NOx conversion at the SCR inlet temperature of 150oC.« less
Effects of Lewis Number on Temperatures of Spherical Diffusion Flames
NASA Technical Reports Server (NTRS)
Santa, K. J.; Sun, Z.; Chao, B. H.; Sunderland, P. B.; Axelbaum, R. I.; Urban, D. L.; Stocker, D. P.
2007-01-01
Spherical diffusion flames supported on a porous sphere were studied numerically and experimentally. Experiments were performed in 2.2 s and 5.2 s microgravity facilities. Numerical results were obtained from a Chemkin-based program. The program simulates flow from a porous sphere into a quiescent environment, yields both steady-state and transient results, and accounts for optically thick gas-phase radiation. The low flow velocities and long residence times in these diffusion flames lead to enhanced radiative and diffusive effects. Despite similar adiabatic flame temperatures, the measured and predicted temperatures varied by as much as 700 K. The temperature reduction correlates with flame size but characteristic flow times and, importantly, Lewis number also influence temperature. The numerical results show that the ambient gas Lewis number would have a strong effect on flame temperature if the flames were steady and nonradiating. For example, a 10% decrease in Lewis number would increase the steady-state flame temperature by 200 K. However, for these transient, radiating flames the effect of Lewis number is small. Transient predictions of flame sizes are larger than those observed in microgravity experiments. Close agreement could not be obtained without either increasing the model s thermal and mass diffusion properties by 30% or reducing mass flow rate by 25%.
The United States Army Medical Department Journal. October - December 2012
2012-12-01
assess effect on weight change following injury. Nutritional programs aimed at smaller meal consumption , inclusion of breakfast, making healthier...electrocardiography, blood pres- sure, oxygen saturation, end-tidal carbon dioxide, and rectal temperatures were continuously monitored for the...blood pressure, oxygen saturation, end-tidal carbon dioxide, and rectal temperatures . Body temperature was maintained greater than 36.0°C. When
Review of Rover fuel element protective coating development at Los Alamos
NASA Technical Reports Server (NTRS)
Wallace, Terry C.
1991-01-01
The Los Alamos Scientific Laboratory (LASL) entered the nuclear propulsion field in 1955 and began work on all aspects of a nuclear propulsion program with a target exhaust temperature of about 2750 K. A very extensive chemical vapor deposition coating technology for preventing catastrophic corrosion of reactor core components by the high temperature, high pressure hydrogen propellant gas was developed. Over the 17-year term of the program, more than 50,000 fuel elements were coated and evaluated. Advances in performance were achieved only through closely coupled interaction between the developing fuel element fabrication and protective coating technologies. The endurance of fuel elements in high temperature, high pressure hydrogen environment increased from several minutes at 2000 K exit gas temperature to 2 hours at 2440 K exit gas temperature in a reactor test and 10 hours at 2350 K exit gas temperature in a hot gas test. The purpose of this paper is to highlight the rationale for selection of coating materials used (NbC and ZrC), identify critical fuel element-coat interactions that had to be modified to increase system performance, and review the evolution of protective coating technology.
Simulation of the wastewater temperature in sewers with TEMPEST.
Dürrenmatt, David J; Wanner, Oskar
2008-01-01
TEMPEST is a new interactive simulation program for the estimation of the wastewater temperature in sewers. Intuitive graphical user interfaces assist the user in managing data, performing calculations and plotting results. The program calculates the dynamics and longitudinal spatial profiles of the wastewater temperature in sewer lines. Interactions between wastewater, sewer air and surrounding soil are modeled in TEMPEST by mass balance equations, rate expressions found in the literature and a new empirical model of the airflow in the sewer. TEMPEST was developed as a tool which can be applied in practice, i.e., it requires as few input data as possible. These data include the upstream wastewater discharge and temperature, geometric and hydraulic parameters of the sewer, material properties of the sewer pipe and surrounding soil, ambient conditions, and estimates of the capacity of openings for air exchange between sewer and environment. Based on a case study it is shown how TEMPEST can be applied to estimate the decrease of the downstream wastewater temperature caused by heat recovery from the sewer. Because the efficiency of nitrification strongly depends on the wastewater temperature, this application is of practical relevance for situations in which the sewer ends at a nitrifying wastewater treatment plant.
Development of high temperature liquid lubricants for low-heat rejection: Heavy duty diesel engines
NASA Technical Reports Server (NTRS)
Wiczynski, P. D.; Marolewski, T. A.
1993-01-01
The objective of this DOE program was to develop a liquid lubricant that will allow advanced diesel engines to operate at top ring reversal temperatures approaching 500 C and sump temperatures approaching 250 C. The lubricants developed demonstrated at marginal increase in sump temperature capability, approximately 15 C, and an increase in top ring reversal temperature. A 15W-40 synthetic lubricant designated HTL-4 was the best lubricant developed in terms of stability, wear control, deposit control dispersancy, and particulate emissions.
NASA Astrophysics Data System (ADS)
Carrete, Jesús; Vermeersch, Bjorn; Katre, Ankita; van Roekeghem, Ambroise; Wang, Tao; Madsen, Georg K. H.; Mingo, Natalio
2017-11-01
almaBTE is a software package that solves the space- and time-dependent Boltzmann transport equation for phonons, using only ab-initio calculated quantities as inputs. The program can predictively tackle phonon transport in bulk crystals and alloys, thin films, superlattices, and multiscale structures with size features in the nm- μm range. Among many other quantities, the program can output thermal conductances and effective thermal conductivities, space-resolved average temperature profiles, and heat-current distributions resolved in frequency and space. Its first-principles character makes almaBTE especially well suited to investigate novel materials and structures. This article gives an overview of the program structure and presents illustrative examples for some of its uses. PROGRAM SUMMARY Program Title:almaBTE Program Files doi:http://dx.doi.org/10.17632/8tfzwgtp73.1 Licensing provisions: Apache License, version 2.0 Programming language: C++ External routines/libraries: BOOST, MPI, Eigen, HDF5, spglib Nature of problem: Calculation of temperature profiles, thermal flux distributions and effective thermal conductivities in structured systems where heat is carried by phonons Solution method: Solution of linearized phonon Boltzmann transport equation, Variance-reduced Monte Carlo
High Temperature Metallic Seal Development For Aero Propulsion and Gas Turbine Applications
NASA Technical Reports Server (NTRS)
More, Greg; Datta, Amit
2006-01-01
A viewgraph presentation on metallic high temperature static seal development at NASA for gas turbine applications is shown. The topics include: 1) High Temperature Static Seal Development; 2) Program Review; 3) Phase IV Innovative Seal with Blade Alloy Spring; 4) Spring Design; 5) Phase IV: Innovative Seal with Blade Alloy Spring; 6) PHase IV: Testing Results; 7) Seal Seating Load; 8) Spring Seal Manufacturing; and 9) Other Applications for HIgh Temperature Spring Design
NEET Enhanced Micro Pocket Fission Detector for High Temperature Reactors - FY15 Status Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Unruh, Troy; McGregor, Douglas; Ugorowski, Phil
2015-09-01
A new project, that is a collaboration between the Idaho National Laboratory (INL), the Kansas State University (KSU), and the French Atomic Energy Agency, Commissariat à l'Énergie Atomique et aux Energies Alternatives, (CEA), has been initiated by the Nuclear Energy Enabling Technologies (NEET) Advanced Sensors and Instrumentation (ASI) program for developing and testing High Temperature Micro-Pocket Fission Detectors (HT MPFD), which are compact fission chambers capable of simultaneously measuring thermal neutron flux, fast neutron flux and temperature within a single package for temperatures up to 800 °C. The MPFD technology utilizes a small, multi-purpose, robust, in-core parallel plate fission chambermore » and thermocouple. As discussed within this report, the small size, variable sensitivity, and increased accuracy of the MPFD technology represent a revolutionary improvement over current methods used to support irradiations in US Material Test Reactors (MTRs). Previous research conducted through NEET ASI1-3 has shown that the MPFD technology could be made robust and was successfully tested in a reactor core. This new project will further the MPFD technology for higher temperature regimes and other reactor applications by developing a HT MPFD suitable for temperatures up to 800 °C. This report summarizes the research progress for year one of this three year project. Highlights from research accomplishments include: A joint collaboration was initiated between INL, KSU, and CEA. Note that CEA is participating at their own expense because of interest in this unique new sensor. An updated HT MPFD design was developed. New high temperature-compatible materials for HT MPFD construction were procured. Construction methods to support the new design were evaluated at INL. Laboratory evaluations of HT MPFD were initiated. Electrical contact and fissile material plating has been performed at KSU. Updated detector electronics are undergoing evaluations at KSU. A project meeting was held at KSU to discuss the roles and responsibilities between INL and KSU for development of the HT MPFDs. Provide input to various irradiation programs for installation of the MPFD technology in irradiation tests. As documented in this report, FY15 funding has allowed the project to meet year one planned accomplishments to develop a HT MPFD that offers US MTR users enhanced capabilities for real-time measurement of flux and temperature with a single detector. In addition, the accomplishments of this project have attracted funding from other Department of Energy Office of Nuclear Energy (DOE-NE) programs for additional applications. The work in those programs will build on current activities completed in this NEETASI HT MPFD project, but the MPFD will be specifically tailored to meet their program needs.« less
Middle Atmosphere Program. Handbook for MAP, Volume 7
NASA Technical Reports Server (NTRS)
Sechrist, C. F., Jr. (Editor)
1982-01-01
Completed and proposed research relating to the Middle Atmosphere Program is discussed. Emphasis is given to the winters in the Northern Hemisphere, the equatorial atmosphere, meteor observation, solar irradiance, atmospheric temperature, geopotential height, atmospheric circulation, and electrodynamics.
Advanced vehicle emission reduction sensor program (FED-SAVER).
DOT National Transportation Integrated Search
2008-09-01
The FED-SAVER program refined and continued the development of an in-cylinder, high temperature pressure sensor by demonstrating that it can be successfully inserted into diesel engines for routine feedback control of each individual cylinder. There ...
Program For Analysis Of Metal-Matrix Composites
NASA Technical Reports Server (NTRS)
Murthy, P. L. N.; Mital, S. K.
1994-01-01
METCAN (METal matrix Composite ANalyzer) is computer program used to simulate computationally nonlinear behavior of high-temperature metal-matrix composite structural components in specific applications, providing comprehensive analyses of thermal and mechanical performances. Written in FORTRAN 77.
An Overview of 2014 SBIR Phase I and Phase II Materials Structures for Extreme Environments
NASA Technical Reports Server (NTRS)
Nguyen, Hung D.; Steele, Gynelle C.; Morris, Jessica R.
2015-01-01
NASA's Small Business Innovation Research (SBIR) program focuses on technological innovation by investing in development of innovative concepts and technologies to help NASA mission directorates address critical research needs for Agency programs. This report highlights nine of the innovative SBIR 2014 Phase I and Phase II projects that emphasize one of NASA Glenn Research Center's six core competencies-Materials and Structures for Extreme Environments. The technologies cover a wide spectrum of applications such as high temperature environmental barrier coating systems, deployable space structures, solid oxide fuel cells, and self-lubricating hard coatings for extreme temperatures. Each featured technology describes an innovation, technical objective, and highlights NASA commercial and industrial applications. This report provides an opportunity for NASA engineers, researchers, and program managers to learn how NASA SBIR technologies could help their programs and projects, and lead to collaborations and partnerships between the small SBIR companies and NASA that would benefit both.
NASA Technical Reports Server (NTRS)
Bradley, P. F.; Throckmorton, D. A.
1981-01-01
A study was completed to determine the sensitivity of computed convective heating rates to uncertainties in the thermal protection system thermal model. Those parameters considered were: density, thermal conductivity, and specific heat of both the reusable surface insulation and its coating; coating thickness and emittance; and temperature measurement uncertainty. The assessment used a modified version of the computer program to calculate heating rates from temperature time histories. The original version of the program solves the direct one dimensional heating problem and this modified version of The program is set up to solve the inverse problem. The modified program was used in thermocouple data reduction for shuttle flight data. Both nominal thermal models and altered thermal models were used to determine the necessity for accurate knowledge of thermal protection system's material thermal properties. For many thermal properties, the sensitivity (inaccuracies created in the calculation of convective heating rate by an altered property) was very low.
NASA-EPA automotive thermal reactor technology program
NASA Technical Reports Server (NTRS)
Blankenship, C. P.; Hibbard, R. R.
1972-01-01
The status of the NASA-EPA automotive thermal reactor technology program is summarized. This program is concerned primarily with materials evaluation, reactor design, and combustion kinetics. From engine dynamometer tests of candidate metals and coatings, two ferritic iron alloys (GE 1541 and Armco 18-SR) and a nickel-base alloy (Inconel 601) offer promise for reactor use. None of the coatings evaluated warrant further consideration. Development studies on a ceramic thermal reactor appear promising based on initial vehicle road tests. A chemical kinetic study has shown that gas temperatures of at least 900 K to 1000 K are required for the effective cleanup of carbon monoxide and hydrocarbons, but that higher temperatures require shorter combustion times and thus may permit smaller reactors.
Engineering design of a high-temperature superconductor current lead
NASA Astrophysics Data System (ADS)
Niemann, R. C.; Cha, Y. S.; Hull, J. R.; Daugherty, M. A.; Buckles, W. E.
As part of the US Department of Energy's Superconductivity Pilot Center Program, Argonne National Laboratory and Superconductivity, Inc., are developing high-temperature superconductor (HTS) current leads suitable for application to superconducting magnetic energy storage systems. The principal objective of the development program is to design, construct, and evaluate the performance of HTS current leads suitable for near-term applications. Supporting objectives are to (1) develop performance criteria; (2) develop a detailed design; (3) analyze performance; (4) gain manufacturing experience in the areas of materials and components procurement, fabrication and assembly, quality assurance, and cost; (5) measure performance of critical components and the overall assembly; (6) identify design uncertainties and develop a program for their study; and (7) develop application-acceptance criteria.
National Aerospace Plane Integrated Fuselage/Cryotank Risk Reduction program
NASA Astrophysics Data System (ADS)
Dayton, K. E.
1993-06-01
The principal objectives and results of the National Aerospace Plane (NASP) Integrated Risk Reduction program are briefly reviewed. The program demonstrated the feasibility of manufacturing lightweight advanced composite materials for single-stage-to-orbit hypersonic flight vehicle applications. A series of combined load simulation tests (thermal, mechanical, and cryogenic) demonstrated proof of concept performance for an all unlined composite cryogenic fuel tank with flat end bulkheads and a high-temperature thin-shell advanced composite fuselage. Temperatures of the fuselage were as high as 1300 F, with 100 percent bending and shear loads applied to the tank while filled with 850 gallons of cryogenic fluid hydrogen (-425 F). Leak rates measured on and around the cryotank shell and bulkheads were well below acceptable levels.
Fixture tests bellows reliability through repetitive pressure/temperature cycling
NASA Technical Reports Server (NTRS)
Levinson, C.
1967-01-01
Fixture explores the reliability of bellows used in precision in inertial systems. The fixture establishes the ability of the bellows to withstand repetitive over-stress pressure cycling at elevated temperatures. It is applicable in quality control and reliability programs.
Effects of temperature on the development of low permeability in concretes.
DOT National Transportation Integrated Search
1998-02-01
This study evaluated the effects of temperature on the strength and permeability of concretes containing pozzolans (fly ash and silica fume) and slag. Two test programs were conducted. In the first, one control and five experimental mixtures containi...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lara-Curzio, Edgar; Rios, Orlando; Marquez-Rossy, Andres Emilio
ORNL collaborated with Faurecia Interior Systems to investigate the feasibility of developing a thermomagnetic preventive maintenance program for nickel tooling used in powder slush molding. It was found that thermal treatments at temperatures greater than 500°C can anneal strain hardening in nickel tooling and a range of temperatures and times for effective thermal annealing were identified. It was also observed that magnetic fields applied during thermal annealing do not alter the kinetics of strain hardening annealing. The results obtained in this investigation provide a foundation for establishing a preventive maintenance program for nickel tooling.
Petkovic, Lucia M.; Ginosar, Daniel M.
2014-01-01
Catalytic performance of Mo/HZSM5 and Ru-Mo/HZSM5 catalysts prepared by vaporization-deposition of molybdenum trioxide and impregnation with ammonium heptamolybdate was analyzed in terms of catalyst activity and selectivity, nitrogen physisorption analyses, temperature-programmed oxidation of carbonaceous residues, and temperature-programmed reduction. Vaporization-deposition rendered the catalyst more selective to ethylene and coke than the catalyst prepared by impregnation. This result was assigned to lower interaction of molybdenum carbide with the zeolite acidic sites.
NASA Technical Reports Server (NTRS)
1972-01-01
A fuel cell technology program was established to advance the state-of-the art of hydrogen oxygen fuel cells using low temperature, potassium hydroxide electrolyte technology as the base. Cell and component testing confirmed that low temperature, potassium hydroxide electrolyte technology is compatible with the requirements of the space shuttle Phase B contractors. Testing of the DM-1 powerplant demonstrated all of the important requirements of the shuttle except operating life. Testing also identified DM-1 powerplant life limiting mechanisms; hydrogen pump gear wear and pressurization of the cell stack over its design limits.
Performance Characteristics of Lithium-Ion Prototype Batteries for Mars Surveyor Program 2001 Lander
NASA Technical Reports Server (NTRS)
Smart, M. C.; Ratnakumar, B. V.; Whitcanack, L.; Surampudi, S.; Byers, J.; Marsh, R. A.
2000-01-01
A viewgraph presentation outlines the scientific payload, expected launch date and tasks, and an image of the Mars Surveyor 2001 Lander components. The Lander's battery specifications are given. The program objectives for the Li-ion cells for the Lander are listed, and results performance evaluation and cycle life performance tests are outlined for different temperatures. Cell charge characteristics are described, and test data is presented for charge capacity at varying temperatures. Capacity retention and storage characteristics tests are described and results are shown.
Life prediction and constitutive models for engine hot section anisotropic materials program
NASA Technical Reports Server (NTRS)
Nissley, D. M.; Meyer, T. G.
1992-01-01
This report presents the results from a 35 month period of a program designed to develop generic constitutive and life prediction approaches and models for nickel-based single crystal gas turbine airfoils. The program is composed of a base program and an optional program. The base program addresses the high temperature coated single crystal regime above the airfoil root platform. The optional program investigates the low temperature uncoated single crystal regime below the airfoil root platform including the notched conditions of the airfoil attachment. Both base and option programs involve experimental and analytical efforts. Results from uniaxial constitutive and fatigue life experiments of coated and uncoated PWA 1480 single crystal material form the basis for the analytical modeling effort. Four single crystal primary orientations were used in the experiments: (001), (011), (111), and (213). Specific secondary orientations were also selected for the notched experiments in the optional program. Constitutive models for an overlay coating and PWA 1480 single crystal material were developed based on isothermal hysteresis loop data and verified using thermomechanical (TMF) hysteresis loop data. A fatigue life approach and life models were selected for TMF crack initiation of coated PWA 1480. An initial life model used to correlate smooth and notched fatigue data obtained in the option program shows promise. Computer software incorporating the overlay coating and PWA 1480 constitutive models was developed.
The effectiveness of Google GLASS as a vital signs monitor in surgery: A simulation study.
Iqbal, Mohammed Husnain; Aydin, Abdullatif; Lowdon, Alexandra; Ahmed, Hamza Ibn; Muir, Gordon H; Khan, M Shamim; Dasgupta, Prokar; Ahmed, Kamran
2016-12-01
To assess the effectiveness of the Google GLASS as a vital signs monitor in a surgical setting and identify potential uses. This prospective, observational and comparative study recruited novice (n = 24), intermediate (n = 8) and expert urologists (n = 5). All candidates performed a procedure on the GreenLight Simulator within a simulated setting using a standard vital signs monitor and then the Google GLASS. The time taken to respond to abnormal vital signs during both sessions was recorded. A quantitative survey was used to assess the usability and acceptability of the Google GLASS surgery. The majority (84%) of participants responded quicker to abnormal signs with the Google GLASS compared to a standard monitor (p = 0.0267). The average simulation score during a standard-monitor and GLASS-session scored to be statistically insignificant (p = 0.253). All parameters of simulation were also similar in both sessions including average sweep speed (p = 0.594), average blood loss (p = 0.761) and average grams vaporised (p = 0.102). Surgical performance between both sessions was similar and not hampered by the use of Google GLASS. Furthermore, 81% of candidates stated the GLASS was comfortable to wear during the procedure. This study has demonstrated that head-mounted displays such as the Google GLASS are potentially useful in surgery to aid patient care without hampering the surgeons view. It is hoped that the innovation and evolution of these devices triggers the potential future application of such devices within the medical field. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.
Williams, G A; O'Brien, R S; Grzechnik, M; Wise, K N
2017-04-28
A group of Aboriginal people was camped at Wallatinna in South Australia, ~170 km downwind from Emu Field, where an atomic test (the Totem 1 test) was carried out at 07.00 on 15 October 1953 local time (21.30 on 14 October 1953 GMT (Greenwich Mean Time)). They left the camp ~24 hours later. These people stated that a phenomenon that has become known as a 'black mist' rolled through their camp site ~5 hours after detonation and that some of them subsequently became sick, displaying skin reddening and nausea. They feared that the sickness was a result of exposure to high levels of radiation. The purpose of this paper is to determine if these people could have received ionising radiation doses high enough to cause the symptoms displayed. The methodology used for the dose estimates is described in the paper. The exposure modes considered were external exposure due to the passage of a contaminated plume over the camp site, inhalation of material from this plume, external exposure from material deposited on the ground as the plume passed, and consumption of contaminated food and water. The contaminants considered in the airborne cloud and the ground plume were fission products and unburnt plutonium from the nuclear detonation, and neutron activation products caused by vaporisation of the tower used to position the weapon. The source was approximated by a line source. An upper estimate of the effective doses received is ~4 mSv, which is well below the level at which acute radiation effects are observed. This estimate is consistent with earlier assessments, which did not consider inhalation of the contribution from neutron activation products. © Crown copyright 2016.
NASA Astrophysics Data System (ADS)
Green, David N.; Evers, Läslo G.; Fee, David; Matoza, Robin S.; Snellen, Mirjam; Smets, Pieter; Simons, Dick
2013-05-01
Explosive submarine volcanic processes are poorly understood, due to the difficulties associated with both direct observation and continuous monitoring. In this study hydroacoustic, infrasound, and seismic signals recorded during the May 2010 submarine eruption of South Sarigan seamount, Marianas Arc, are used to construct a detailed event chronology. The signals were recorded on stations of the International Monitoring System, which is a component of the verification measures for the Comprehensive Nuclear-Test-Ban Treaty. Numerical hydroacoustic and infrasound propagation modelling confirms that viable propagation paths from the source to receivers exist, and provide traveltimes allowing signals recorded on the different technologies to be associated. The eruption occurred in three stages, separated by three-hour periods of quiescence. 1) A 46 h period during which broadband impulsive hydroacoustic signals were generated in clusters lasting between 2 and 13 min. 95% of the 7602 identified events could be classified into 4 groups based on their waveform similarity. The time interval between clusters decreased steadily from 80 to 25 min during this period. 2) A five-hour period of 10 Hz hydroacoustic tremor, interspersed with large-amplitude, broadband signals. Associated infrasound signals were also recorded at this time. 3) An hour-long period of transient broadband events culminated in two large-amplitude hydroacoustic events and one broadband infrasound signal. A speculative interpretation, consistent with the data, suggests that during phase (1) transitions between endogenous dome growth and phreatomagmatic explosions occurred with the magma ascent rate accelerating throughout the period; during phase (2) continuous venting of fragmented magma occurred, and was powerful enough to breach the sea surface. During the climactic phase (3) discrete powerful explosions occurred, and sufficient seawater was vaporised to produce the contemporaneous 12 km altitude steam plume.
Mass-spectroscopic study of the influence of nozzle material on high-pressure SF6 arcs
NASA Astrophysics Data System (ADS)
Meier, R.; Kneubühl, F. K.; Schötzau, H. J.
1989-03-01
The interrupting capability of a gas-blast high-voltage circuit breaker (CB) is mainly determined by the self-induced pressure rise caused by the thermal arc energy, the composition of the arc plasma and the chemical reactions occuring during and after current interruption. We have studied the nozzle materials boron nitride (BN), quartz (SiO2), polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene (ETFE), polyethylene (PE) and epoxy resin (ER) with respect to their influence on these processes with the aid of a model circuit breaker (MCB). Direct measurements of the arc-induced pressure rise reveal that the portion of the arc energy available for the pressure rise varies greatly (˜20% 65%) with the properties of the nozzle material. Nozzle erosion is significantly higher for materials with high values (e.g. polymers). Therefore, the lifetime of polymer nozzles is considerably shorter than that of ceramic nozzles. We have investigated the influence of the nozzle material on the decomposition products formed in the arc discharge of our MCB by studying the composition and time dependence of these products. The MCB was directly attached to the time-of-flight mass spectrometer (TOFMS) with the aid of a molecular-beam sampling system, which allowed real-time measurements of the arced gas during and after current interruption, thus providing information on the ablation mechanism and on the reaction kinetics of vaporised nozzle material with dissociated SF6. The most abundant long-lived reaction products are SF4, SOF2, C2H2, CO, and CS2. Their formation rates have been determined as functions of the nozzle material. With respect to quantities and properties of decomposition products, ceramics are superior to polymers since they form only small concentrations of corrosive and toxic products.
Luckett, T; Phillips, J; Lintzeris, N; Allsop, D; Lee, J; Solowij, N; Martin, J; Lam, L; Aggarwal, R; McCaffrey, N; Currow, D; Chye, R; Lovell, M; McGregor, I; Agar, M
2016-11-01
Australian clinical trials are planned to evaluate medicinal cannabis in a range of clinical contexts. To explore the preferences, attitudes and beliefs of patients eligible and willing to consider participation in a clinical trial of medicinal cannabis for poor appetite and appetite-related symptoms from advanced cancer. A cross-sectional anonymous survey was administered from July to December 2015 online and in eight adult outpatient palliative care and/or cancer services. Respondents were eligible if they were ≥18 years, had advanced cancer and poor appetite/taste problems/weight loss and might consider participating in a medicinal cannabis trial. Survey items focused on medicinal rather than recreational cannabis use and did not specify botanical or pharmaceutical products. Items asked about previous medicinal cannabis use and preferences for delivery route and invited comments and concerns. There were 204 survey respondents, of whom 26 (13%) reported prior medicinal cannabis use. Tablets/capsules were the preferred delivery mode (n = 144, 71%), followed by mouth spray (n = 84, 42%) and vaporiser (n = 83, 41%). Explanations for preferences (n = 134) most commonly cited convenience (n = 66; 49%). A total of 82% (n = 168) of respondents indicated that they had no trial-related concerns, but a small number volunteered concerns about adverse effects (n = 14) or wanted more information/advice (n = 8). Six respondents volunteered a belief that cannabis might cure cancer, while two wanted assurance of efficacy before participating in a trial. Justification of modes other than tablets/capsules and variable understanding about cannabis and trials will need addressing in trial-related information to optimise recruitment and ensure that consent is properly informed. © 2016 Royal Australasian College of Physicians.
Casado, Juan C; O'Connor, Carlos; Angulo, María S; Adrián, José A
2016-01-01
With the development of new ENT techniques, many male transsexuals who wish to become women usually request a surgical procedure to raise the fundamental frequency of the voice (feminization). The ENT specialist and the voice-therapist have to use an interdisciplinary approach to this growing social demand. The aim of this study was to show the results in a group of transsexual patients after Wendler's anterior synechiae, with additional voice-therapy treatment. Ten male transexulas who wish to become women patients who had Wendler glottoplasty and voice-therapy were assessed. The surgical procedure consisted of a de-epithelialization of the anterior third of both vocal folds; this area was sutured and the surface of both vocal folds was vaporised with laser diode. Pre- and postsurgery voice assessment consisted of measuring fundamental frequency (Fo) and maximum phonation time, administering the transgender self-assessment questionnaire (TSEQ) and obtaining perceptual voice assessment by inter-rater agreement. All the male transsexuals who wish to become women patients significantly increased their Fo (106 Hz on average) after the treatment. Furthermore, significant improvements were shown in self-reported satisfaction and in the degree of voice feminization. No improvements in the maximum phonation time were observed. Wendler glottoplasty is a surgical procedure to contribute to feminising the voice, with good medium-term results and without noteworthy medical complications. The increase in vocal tone was observed using several pre- and post-surgery control measures and voice therapy. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.
Suzuki, Taku T; Sakaguchi, Isao
2016-01-01
Selective concentration of ultra-trace components in air-like gases has an important application in analyzing volatile organic compounds in the gas. In the present study, we examined quench-condensation of the sample gas on a ZnO substrate below 50 K followed by temperature programmed desorption (TPD) (low temperature TPD) as a selective gas concentration technique. We studied two specific gases in the normal air; krypton as an inert gas and acetone as a reactive gas. We evaluated the relationship between the operating condition of low temperature TPD and the lowest detection limit. In the case of krypton, we observed the selective concentration by exposing at 6 K followed by thermal desorption at about 60 K. On the other hand, no selectivity appeared for acetone although trace acetone was successfully concentrated. This is likely due to the solvent effect by a major component in the air, which is suggested to be water. We suggest that pre-condensation to remove the water component may improve the selectivity in the trace acetone analysis by low temperature TPD.
Temperature-programmed deoxygenation of acetic acid on molybdenum carbide catalysts
Nash, Connor P.; Farberow, Carrie A.; Hensley, Jesse E.
2017-02-07
Temperature programmed reaction (TPRxn) is a simple yet powerful tool for screening solid catalyst performance at a variety of conditions. A TPRxn system includes a reactor, furnace, gas and vapor sources, flow control, instrumentation to quantify reaction products (e.g., gas chromatograph), and instrumentation to monitor the reaction in real time (e.g., mass spectrometer). Here, we apply the TPRxn methodology to study molybdenum carbide catalysts for the deoxygenation of acetic acid, an important reaction among many in the upgrading/stabilization of biomass pyrolysis vapors. TPRxn is used to evaluate catalyst activity and selectivity and to test hypothetical reaction pathways (e.g., decarbonylation, ketonization,more » and hydrogenation). Furthermore, the results of the TPRxn study of acetic acid deoxygenation show that molybdenum carbide is an active catalyst for this reaction at temperatures above ca. 300 °C and that the reaction favors deoxygenation (i.e., C-O bond-breaking) products at temperatures below ca. 400 °C and decarbonylation (i.e., C-C bond-breaking) products at temperatures above ca. 400 °C.« less
NASA Astrophysics Data System (ADS)
Ogitsu, T.; Fernandez-Paãella, A.; Correa, A.; Engelhorn, K.; Barbrel, B.; Prendergast, D. G.; Pemmaraju, D.; Beckwith, M.; Kraus, D.; Hamel, S.; Cho, B. I.; Jin, L.; Wong, J.; Heinman, P.; Collins, G. W.; Falcone, R.; Ping, Y.
2016-10-01
We present a study of the electron-phonon coupling of warm dense iron upon femtosecond laser excitation by time-resolved x-ray absorption near edge spectroscopy (XANES). The dynamics of iron in electron-ion non-equilibrium conditions was studied using ab-initio density-functional-theory (DFT) simulations combined with the Two Temperature Model (TTM) where spatial inhomogeneity of electron (and ion) temperature(s) due to short ballistic electron transport length in iron was explicitly taken into consideration. Detailed comparison between our simulation results and experiments indicates that the ion temperature dependence on specific heat and on electron-phonon coupling also plays a relevant role in modeling the relaxation dynamics of electrons and ions. These results are the first experimental evidence of the suppression of the electron-phonon coupling factor of a transition metal at electron temperatures ranging 5000- 10000 K. This work was performed under DOE contract DE-AC52-07NA27344 with support from OFES Early Career program and LLNL LDRD program.
Thermal Protective Coating for High Temperature Polymer Composites
NASA Technical Reports Server (NTRS)
Barron, Andrew R.
1999-01-01
The central theme of this research is the application of carboxylate-alumoxane nanoparticles as precursors to thermally protective coatings for high temperature polymer composites. In addition, we will investigate the application of carboxylate-alumoxane nanoparticle as a component to polymer composites. The objective of this research was the high temperature protection of polymer composites via novel chemistry. The significance of this research is the development of a low cost and highly flexible synthetic methodology, with a compatible processing technique, for the fabrication of high temperature polymer composites. We proposed to accomplish this broad goal through the use of a class of ceramic precursor material, alumoxanes. Alumoxanes are nano-particles with a boehmite-like structure and an organic periphery. The technical goals of this program are to prepare and evaluate water soluble carboxylate-alumoxane for the preparation of ceramic coatings on polymer substrates. Our proposed approach is attractive since proof of concept has been demonstrated under the NRA 96-LeRC-1 Technology for Advanced High Temperature Gas Turbine Engines, HITEMP Program. For example, carbon and Kevlar(tm) fibers and matting have been successfully coated with ceramic thermally protective layers.
EMPRESS: A European Project to Enhance Process Control Through Improved Temperature Measurement
NASA Astrophysics Data System (ADS)
Pearce, J. V.; Edler, F.; Elliott, C. J.; Rosso, L.; Sutton, G.; Andreu, A.; Machin, G.
2017-08-01
A new European project called EMPRESS, funded by the EURAMET program `European Metrology Program for Innovation and Research,' is described. The 3 year project, which started in the summer of 2015, is intended to substantially augment the efficiency of high-value manufacturing processes by improving temperature measurement techniques at the point of use. The project consortium has 18 partners and 5 external collaborators, from the metrology sector, high-value manufacturing, sensor manufacturing, and academia. Accurate control of temperature is key to ensuring process efficiency and product consistency and is often not achieved to the level required for modern processes. Enhanced efficiency of processes may take several forms including reduced product rejection/waste; improved energy efficiency; increased intervals between sensor recalibration/maintenance; and increased sensor reliability, i.e., reduced amount of operator intervention. Traceability of temperature measurements to the International Temperature Scale of 1990 (ITS-90) is a critical factor in establishing low measurement uncertainty and reproducible, consistent process control. Introducing such traceability in situ (i.e., within the industrial process) is a theme running through this project.
Hanh, Nguyen Hong; Jang, Kyungsoo; Yi, Junsin
2016-05-01
We directly deposited amorphous InGaZnO (a-IGZO) nonvolatile memory (NVM) devices with oxynitride-oxide-dioxide (OOO) stack structures on plastic substrate by a DC pulsed magnetron sputtering and inductively coupled plasma chemical vapor deposition (ICPCVD) system, using a low-temperature of 150 degrees C. The fabricated bottom gate a-IGZO NVM devices have a wide memory window with a low operating voltage during programming and erasing, due to an effective control of the gate dielectrics. In addition, after ten years, the memory device retains a memory window of over 73%, with a programming duration of only 1 ms. Moreover, the a-IGZO films show high optical transmittance of over 85%, and good uniformity with a root mean square (RMS) roughness of 0.26 nm. This film is a promising candidate to achieve flexible displays and transparency on plastic substrates because of the possibility of low-temperature deposition, and the high transparent properties of a-IGZO films. These results demonstrate that the a-IGZO NVM devices obtained at low-temperature have a suitable programming and erasing efficiency for data storage under low-voltage conditions, in combination with excellent charge retention characteristics, and thus show great potential application in flexible memory displays.
Physical oceanographic data from the OTEC Punta Tuna, Puerto Rico Site, September 1979-June 1980
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frye, D.; Davison, A.; Leavitt, K.
1981-01-01
The first results of an oceanographic measurement program being conducted off the southeast corner of Puerto Rico are presented. The study site is a proposed OTEC site and is located about 20 km off Punta Tuna. The objectives of the measurement program are to document the physical oceanography of the site as related to the engineering and environmental factors involved in OTEC design and operation. Oceanographic measurements include: (1) a subsurface mooring instrumented with five current, temperature, and pressure recorders; and (2) quarterly hydrographic cruises to measure salinity, temperature, and depth profiles on a grid of 33 stations in themore » vicinity of the mooring site. The first cruise, conducted between 16 and 21 June 1980, included the initial mooring deployment and a CTD (conductivity, temperature, and depth) and XBT (expendable bathythermograph) survey. The CTD/XBT measurements are presented. Also included are results of in situ current, temperature, and pressure measurements made during two previous programs. In September 1979, Coastal Marine Research (CMR) deployed a mooring at approximately the same site as the present mooring. Results from three of these instruments are included. The Naval Underwater Systems Center deployed a mooring at this site in February 1979 and partial results from one instrument on this mooring are also presented. (WHK)« less
Ruiz, B C; Tucker, W K; Kirby, R R
1975-01-01
With a desk-top, programmable calculator, it is now possible to do complex, previously time-consuming computations in the blood-gas laboratory. The authors have developed a program with the necessary algorithms for temperature correction of blood gases and calculation of acid-base variables and intrapulmonary shunt. It was necessary to develop formulas for the Po2 temperature-correction coefficient, the oxyhemoglobin-dissociation curve for adults (withe necessary adjustments for fetal blood), and changes in water vapor pressure due to variation in body temperature. Using this program in conjuction with a Monroe 1860-21 statistical programmable calculator, it is possible to temperature-correct pH,Pco2, and Po2. The machine will compute alveolar-arterial oxygen tension gradient, oxygen saturation (So2), oxygen content (Co2), actual HCO minus 3 and a modified base excess. If arterial blood and mixed venous blood are obtained, the calculator will print out intrapulmonary shunt data (Qs/Qt) and arteriovenous oxygen differences (a minus vDo2). There also is a formula to compute P50 if pH,Pco2,Po2, and measured So2 from two samples of tonometered blood (one above 50 per cent and one below 50 per cent saturation) are put into the calculator.
Fuel freeze-point investigations. Final report, September 1982-March 1984
DOE Office of Scientific and Technical Information (OSTI.GOV)
Desmarais, L.A.; Tolle, F.F.
1984-07-01
The objective of this program was to conduct a detailed assessment of the low-temperature environment to which USAF aircraft are exposed for the purpose of defining a maximum acceptable fuel freeze-point and also to define any operational changes required with the use of a high freeze-point fuel. A previous study of B-52, C-141, and KC-135 operational missions indicated that the -58 C freeze point specification was too conservative. Based on recommendations resulting from the previous program, several improvements in the method of analysis were made, such as: expansion of the atmospheric temperature data base, the addition of ground temperature analysis,more » the addition of fuel-freezing analysis to the one-dimensional fuel-temperature computer program, and the examination of heat transfer in external fuel tanks, such as pylon or tip tanks. The B-52, C-141, and KC-135 mission were analyzed again, along with the operational missions of two tactical airplanes, the A-10 and F-15; -50C was determined to be the maximum allowable freeze point for a general-purpose USAF aviation turbine fuel. Higher freeze points can be tolerated if the probability of operational interference is acceptably low or if operational changes can be made. Study of atmospheric temperatures encountered for the missions of the five-study aircraft indicates that a maximum freeze point of -48 C would not likely create any operational difficulties in Northern Europe.« less
Radiometer Calibrations: Saving Time by Automating the Gathering and Analysis Procedures
NASA Technical Reports Server (NTRS)
Sadino, Jeffrey L.
2005-01-01
Mr. Abtahi custom-designs radiometers for Mr. Hook's research group. Inherently, when the radiometers report the temperature of arbitrary surfaces, the results are affected by errors in accuracy. This problem can be reduced if the errors can be accounted for in a polynomial. This is achieved by pointing the radiometer at a constant-temperature surface. We have been using a Hartford Scientific WaterBath. The measurements from the radiometer are collected at many different temperatures and compared to the measurements made by a Hartford Chubb thermometer with a four-decimal point resolution. The data is analyzed and fit to a fifth-order polynomial. This formula is then uploaded into the radiometer software, enabling accurate data gathering. Traditionally, Mr. Abtahi has done this by hand, spending several hours of his time setting the temperature, waiting for stabilization, taking measurements, and then repeating for other temperatures. My program, written in the Python language, has enabled the data gathering and analysis process to be handed off to a less-senior member of the team. Simply by entering several initial settings, the program will simultaneously control all three instruments and organize the data suitable for computer analyses, thus giving the desired fifth-order polynomial. This will save time, allow for a more complete calibration data set, and allow for base calibrations to be developed. The program is expandable to simultaneously take any type of measurement from up to nine distinct instruments.
Temperature controlled formation of lead/acid batteries
NASA Astrophysics Data System (ADS)
Bungardt, M.
At present, standard formation programs have to accommodate the worst case. This is important, especially in respect of variations in climatic conditions. The standard must be set so that during the hottest weather periods the maximum electrolyte temperature is not exceeded. As this value is defined not only by the desired properties and the recipe of the active mass, but also by type and size of the separators and by the dimensions of the plates, general rules cannot be formulated. It is considered to be advantageous to introduce limiting data for the maximum temperature into a general formation program. The latter is defined so that under normal to good ambient conditions the shortest formation time is achieved. If required, the temperature control will reduce the currents employed in the different steps, according to need, and will extend the formation time accordingly. With computer-controlled formation, these parameters can be readily adjusted to suit each type of battery and can also be reset according to modifications in the preceding processing steps. Such a procedure ensures that: (i) the formation time is minimum under the given ambient conditions; (ii) in the event of malpractice ( e.g. actual program not fitting to size) the batteries will not be destroyed; (iii) the energy consumption is minimized (note, high electrolyte temperature leads to excess gassing). These features are incorporated in the BA/FOS-500 battery formation system developed by Digatron. The operational characteristics of this system are listed in Table 1.
HUMAN--A Comprehensive Physiological Model.
ERIC Educational Resources Information Center
Coleman, Thomas G.; Randall, James E.
1983-01-01
Describes computer program (HUMAN) used to simulate physiological experiments on patient pathology. Program (available from authors, including versions for microcomputers) consists of dynamic interactions of over 150 physiological variables and integrating approximations of cardiovascular, renal, lung, temperature regulation, and some hormone…
Instrumentation of the Red River Bridge at Boyce, Louisiana : final report.
DOT National Transportation Integrated Search
1991-01-01
The report describes the instrumentation program of Red River Bridge at Boyce, Louisiana. The objectives of the program were to measure and evaluate time-dependent deformations, deflections, and temperatures of the Red River Bridge superstructure. To...
Instrumentation of the Red River Bridge at Boyce, Louisiana : final report.
DOT National Transportation Integrated Search
1988-08-01
The report describes the instrumentation program of Red River Bridge at Boyce, Louisiana. The objectives of the program were to measure and evaluate time-dependent deformations, deflections, and temperatures of the Red River Bridge superstructure. To...
Lane, Michael
2013-06-28
Proposed drill sites for intermediate depth temperature gradient holes and/or deep resource confirmation wells. Temperature gradient contours based on shallow TG program and faults interpreted from seismic reflection survey are shown, as are two faults interpreted by seismic contractor Optim but not by Oski Energy, LLC.
Chiu, Rex S; Nahal, Hardeep; Provart, Nicholas J; Gazzarrini, Sonia
2012-01-27
Imbibed seeds integrate environmental and endogenous signals to break dormancy and initiate growth under optimal conditions. Seed maturation plays an important role in determining the survival of germinating seeds, for example one of the roles of dormancy is to stagger germination to prevent mass growth under suboptimal conditions. The B3-domain transcription factor FUSCA3 (FUS3) is a master regulator of seed development and an important node in hormonal interaction networks in Arabidopsis thaliana. Its function has been mainly characterized during embryonic development, where FUS3 is highly expressed to promote seed maturation and dormancy by regulating ABA/GA levels. In this study, we present evidence for a role of FUS3 in delaying seed germination at supraoptimal temperatures that would be lethal for the developing seedlings. During seed imbibition at supraoptimal temperature, the FUS3 promoter is reactivated and induces de novo synthesis of FUS3 mRNA, followed by FUS3 protein accumulation. Genetic analysis shows that FUS3 contributes to the delay of seed germination at high temperature. Unlike WT, seeds overexpressing FUS3 (ML1:FUS3-GFP) during imbibition are hypersensitive to high temperature and do not germinate, however, they can fully germinate after recovery at control temperature reaching 90% seedling survival. ML1:FUS3-GFP hypersensitivity to high temperature can be partly recovered in the presence of fluridone, an inhibitor of ABA biosynthesis, suggesting this hypersensitivity is due in part to higher ABA level in this mutant. Transcriptomic analysis shows that WT seeds imbibed at supraoptimal temperature activate seed-specific genes and ABA biosynthetic and signaling genes, while inhibiting genes that promote germination and growth, such as GA biosynthetic and signaling genes. In this study, we have uncovered a novel function for the master regulator of seed maturation, FUS3, in delaying germination at supraoptimal temperature. Physiologically, this is important since delaying germination has a protective role at high temperature. Transcriptomic analysis of seeds imbibed at supraoptimal temperature reveal that a complex program is in place, which involves not only the regulation of heat and dehydration response genes to adjust cellular functions, but also the activation of seed-specific programs and the inhibition of germination-promoting programs to delay germination. © 2011 Chiu et al; licensee BioMed Central Ltd.
2012-01-01
Background Imbibed seeds integrate environmental and endogenous signals to break dormancy and initiate growth under optimal conditions. Seed maturation plays an important role in determining the survival of germinating seeds, for example one of the roles of dormancy is to stagger germination to prevent mass growth under suboptimal conditions. The B3-domain transcription factor FUSCA3 (FUS3) is a master regulator of seed development and an important node in hormonal interaction networks in Arabidopsis thaliana. Its function has been mainly characterized during embryonic development, where FUS3 is highly expressed to promote seed maturation and dormancy by regulating ABA/GA levels. Results In this study, we present evidence for a role of FUS3 in delaying seed germination at supraoptimal temperatures that would be lethal for the developing seedlings. During seed imbibition at supraoptimal temperature, the FUS3 promoter is reactivated and induces de novo synthesis of FUS3 mRNA, followed by FUS3 protein accumulation. Genetic analysis shows that FUS3 contributes to the delay of seed germination at high temperature. Unlike WT, seeds overexpressing FUS3 (ML1:FUS3-GFP) during imbibition are hypersensitive to high temperature and do not germinate, however, they can fully germinate after recovery at control temperature reaching 90% seedling survival. ML1:FUS3-GFP hypersensitivity to high temperature can be partly recovered in the presence of fluridone, an inhibitor of ABA biosynthesis, suggesting this hypersensitivity is due in part to higher ABA level in this mutant. Transcriptomic analysis shows that WT seeds imbibed at supraoptimal temperature activate seed-specific genes and ABA biosynthetic and signaling genes, while inhibiting genes that promote germination and growth, such as GA biosynthetic and signaling genes. Conclusion In this study, we have uncovered a novel function for the master regulator of seed maturation, FUS3, in delaying germination at supraoptimal temperature. Physiologically, this is important since delaying germination has a protective role at high temperature. Transcriptomic analysis of seeds imbibed at supraoptimal temperature reveal that a complex program is in place, which involves not only the regulation of heat and dehydration response genes to adjust cellular functions, but also the activation of seed-specific programs and the inhibition of germination-promoting programs to delay germination. PMID:22279962
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dennis, B.R.; Lawton, R.G.; Kolar, J.D.
The well-logging operations performed in the Miravalles Geothermal Field in Costa Rica were conducted during two separate field trips. The Phase I program provided the deployment of a suite of high-temperature borehole instruments, including the temperature/rabbit, fluid sampler, and three-arm caliper in Well PGM-3. These same tools were deployed in Well PGM-10 along with an additional survey run with a combination fluid velocity/temperature/pressure instrument used to measure thermodynamic properties under flowing well conditions. The Phase II program complemented Phase I with the suite of tools deployed in Wells PGM-5, PGM-11, and PGM-12. 4 refs., 25 figs., 1 tab.
Applying MHD Results to a Scramjet Vehicle
2007-02-12
flow, arc formation and extinction, high temperature materials, and non-intrusive gas diagnostics. In this report, results from the DOE Program, and...3) Use of demonstrated non-intrusive diagnostics for plasma and boundary layer measurements, and (4) Testing of high - temperature materials for an MHD...cycle systems with researchers in Eindhoven, The Netherlands, and open-cycle systems with personnel at the High Temperature Institute, Moscow, Russia
NASA Technical Reports Server (NTRS)
Anspaugh, B. E.; Miyahira, T. F.; Weiss, R. S.
1979-01-01
Computed statistical averages and standard deviations with respect to the measured cells for each intensity temperature measurement condition are presented. Display averages and standard deviations of the cell characteristics in a two dimensional array format are shown: one dimension representing incoming light intensity, and another, the cell temperature. Programs for calculating the temperature coefficients of the pertinent cell electrical parameters are presented, and postirradiation data are summarized.
NASA Technical Reports Server (NTRS)
Creason, A. S.; Miranda, F. A.
1996-01-01
Knowledge of the microwave properties at cryogenic temperatures of components fabricated using High-Temperature-Superconductors (HTS) is useful in the design of HTS-based microwave circuits. Therefore, fast and reliable characterization techniques have been developed to study the aforementioned properties. In this paper, we discuss computer analysis techniques employed in the cryogenic characterization of HTS-based resonators. The revised data analysis process requires minimal user input. and organizes the data in a form that is easily accessible by the user for further examination. These programs retrieve data generated during the cryogenic characterization at microwave frequencies of HTS based resonators and use it to calculate parameters such as the loaded and unloaded quality factors (Q and Q(sub o), respectively), the resonant frequency (f(sub o)), and the coupling coefficient (k), which are important quantities in the evaluation of HTS resonators. While the data are also stored for further use, the programs allow the user to obtain a graphical representation of any of the measured parameters as a function of temperature soon after the completion of the cryogenic measurement cycle. Although these programs were developed to study planar HTS-based resonators operating in the reflection mode, they could also be used in the cryogenic characterization of two ports (i.e., reflection/transmission) resonators.
275 C Downhole Microcomputer System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chris Hutchens; Hooi Miin Soo
2008-08-31
An HC11 controller IC and along with serial SRAM and ROM support ICs chip set were developed to support a data acquisition and control for extreme temperature/harsh environment conditions greater than 275 C. The 68HC11 microprocessor is widely used in well logging tools for control, data acquisition, and signal processing applications and was the logical choice for a downhole controller. This extreme temperature version of the 68HC11 enables new high temperature designs and additionally allows 68HC11-based well logging tools and MWD tools to be upgraded for high temperature operation in deep gas reservoirs, The microcomputer chip consists of the microprocessormore » ALU, a small boot ROM, 4 kbyte data RAM, counter/timer unit, serial peripheral interface (SPI), asynchronous serial interface (SCI), and the A, B, C, and D parallel ports. The chip is code compatible with the single chip mode commercial 68HC11 except for the absence of the analog to digital converter system. To avoid mask programmed internal ROM, a boot program is used to load the microcomputer program from an external mask SPI ROM. A SPI RAM IC completes the chip set and allows data RAM to be added in 4 kbyte increments. The HC11 controller IC chip set is implemented in the Peregrine Semiconductor 0.5 micron Silicon-on-Sapphire (SOS) process using a custom high temperature cell library developed at Oklahoma State University. Yield data is presented for all, the HC11, SPI-RAM and ROM. The lessons learned in this project were extended to the successful development of two high temperature versions of the LEON3 and a companion 8 Kbyte SRAM, a 200 C version for the Navy and a 275 C version for the gas industry.« less
Low temperature Grüneisen parameter of cubic ionic crystals
NASA Astrophysics Data System (ADS)
Batana, Alicia; Monard, María C.; Rosario Soriano, María
1987-02-01
Title of program: CAROLINA Catalogue number: AATG Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland (see application form in this issue) Computer: IBM/370, Model 158; Installation: Centro de Tecnología y Ciencia de Sistemas, Universidad de Buenos Aires Operating system: VM/370 Programming language used: FORTRAN High speed storage required: 3 kwords No. of bits in a word: 32 Peripherals used: disk IBM 3340/70 MB No. of lines in combined program and test deck: 447
NASA Astrophysics Data System (ADS)
Hamada, Y.; Saito, S.; Sanada, Y.; Masaki, Y.; Moe, K.; Kido, Y. N.; Kumagai, H.; Takai, K.; Suzuki, K.
2015-12-01
In July of 2014, offshore drillings on Iheya-North Knoll, Okinawa Trough, was executed as part of Next-generation technology for ocean resources survey, which is a research program in Cross-ministerial Strategic Innovation Promotion Program (SIP). In this expedition, logging-while- drilling (LWD) and measuring-while-drilling (MWD) were inserted into 6 holes (C9011 - C9016) to investigate spatial distribution of hydrothermal deposit and geothermal fluid reservoir. Both of these tools included annular pressure-while-drilling (APWD). Annular pressure and temperature were monitored by the APWD to detect possible exceedingly-high-temperature geofluid. In addition, drilling fluid was continuously circulated at sufficient flow rate to protect LWD tools against high temperature (non-stop driller system). At C9012 and C9016, the LWD tool clearly detected pressure and temperature anomaly at 234 meter below the seafloor (mbsf) and 80 mbsf, respectively. Annular pressure and temperature quickly increases at that depth and it would reflect the injection of high-temperature fluid. During the drilling, however, drilling water was continuously circulated at high flow-rate (2600L/min) and the measured temperature is not exactly in-situ temperature. To investigate the detail of the heat source, such as in-situ temperature and quantity of heat, we performed numerical analyses of thermal fluid and energy-balance assuming injection of high-temperature fluid. We combined pressure loss theory of double cylinders and temperature equation to replicate the fluid flow and its temperature between borehole wall and drilling pipe during the thermofluid injection. As the result, we estimated the temperature and the volume of injected fluid to be 115oC~ and 17.3 m3, respectively (at C9012) from the calculation. This temperature is lower than that of a hydrothermall vent which had been found near the hole (300oC).
Development of a prototype automatic controller for liquid cooling garment inlet temperature
NASA Technical Reports Server (NTRS)
Weaver, C. S.; Webbon, B. W.; Montgomery, L. D.
1982-01-01
The development of a computer control of a liquid cooled garment (LCG) inlet temperature is descirbed. An adaptive model of the LCG is used to predict the heat-removal rates for various inlet temperatures. An experimental system that contains a microcomputer was constructed. The LCG inlet and outlet temperatures and the heat exchanger outlet temperature form the inputs to the computer. The adaptive model prediction method of control is successful during tests where the inlet temperature is automatically chosen by the computer. It is concluded that the program can be implemented in a microprocessor of a size that is practical for a life support back-pack.
NASA Technical Reports Server (NTRS)
Bade, W. L.; Yos, J. M.
1975-01-01
A computer program for calculating quasi-one-dimensional gas flow in axisymmetric and two-dimensional nozzles and rectangular channels is presented. Flow is assumed to start from a state of thermochemical equilibrium at a high temperature in an upstream reservoir. The program provides solutions based on frozen chemistry, chemical equilibrium, and nonequilibrium flow with finite reaction rates. Electronic nonequilibrium effects can be included using a two-temperature model. An approximate laminar boundary layer calculation is given for the shear and heat flux on the nozzle wall. Boundary layer displacement effects on the inviscid flow are considered also. Chemical equilibrium and transport property calculations are provided by subroutines. The code contains precoded thermochemical, chemical kinetic, and transport cross section data for high-temperature air, CO2-N2-Ar mixtures, helium, and argon. It provides calculations of the stagnation conditions on axisymmetric or two-dimensional models, and of the conditions on the flat surface of a blunt wedge. The primary purpose of the code is to describe the flow conditions and test conditions in electric arc heated wind tunnels.
Reference manual for the Thermal Analyst's Help Desk Expert System
NASA Technical Reports Server (NTRS)
Ormsby, Rachel A.
1994-01-01
This document provides technical information and programming guidance for the maintenance and future development of the Thermal Analyst's Help Desk. Help Desk is an expert system that operates within the EXSYSTM expert system shell, and is used to determine first approximations of thermal capacity for spacecraft and instruments. The five analyses supported in Help Desk are: (1) surface area required for a radiating surface, (2) equilibrium temperature of a surface, (3) enclosure temperature and heat loads for a defined position in orbit, (4) enclosure temperature and heat loads over a complete orbit and, (5) selection of appropriate surface properties. The two geometries supported by Help Desk are a single flat plate and a rectangular box enclosure. The technical information includes the mathematical approach and analytical derivations used in the analyses such as: radiation heat balance, view factor calculation, and orbit determination with coordinate transformation. The programming guide for developers describes techniques for enhancement of Help Desk. Examples are provided showing the addition of new features, user interface development and enhancement, and external program interfaces.
High temperature oxidation-resistant thruster research
NASA Technical Reports Server (NTRS)
Wooten, John R.; Lansaw, P. Tina
1990-01-01
A program was conducted for NASA-LeRC by Aerojet Propulsion Division to establish the technology base for a new class of long-life, high-performance, radiation-cooled bipropellant thrusters capable of operation at temperatures over 2200 C (4000 F). The results of a systematic, multi-year program are described starting with the preliminary screening tests which lead to the final material selection. Life greater than 15 hours was demonstrated on a workhorse iridium-lined rhenium chamber at chamber temperatures between 2000 and 2300 C (3700 and 4200 F). The chamber was fabricated by the Chemical Vapor Deposition at Ultramet. The program culminated in the design, fabrication, and hot-fire test of an NTO/MMH 22-N (5-lbF) class thruster containing a thin wall iridium-lined rhenium thrust chamber with a 150:1 area ratio nozzle. A specific impulse of 310 seconds was measured and front-end thermal management was achieved for steady state and several pulsing duty cycles. The resulting design represents a 20 second specific impulse improvement over conventional designs in which the use of disilicide coated columbium chambers limit operation to 1300 C (2400 F).
Third Generation RLV Structural Seal Development Programs at NASA GRC
NASA Technical Reports Server (NTRS)
Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; DeMange, Jeffrey J.
2002-01-01
NASA GRC's work on high temperature structural seal development began in the late 1980's and early 1990's under the NASP (National Aero-Space Plane) project. Bruce Steinetz led the in-house propulsion system seal development program and oversaw industry efforts for propulsion system and airframe seal development for this vehicle. a propulsion system seal location in the NASP engine is shown. The seals were located along the edge of a movable panel in the engine to seal the gap between the panel and adjacent engine sidewalls. More recently, we worked with Rocketdyne on high temperature seals for the linear aerospike engine ramps. In applications such as the former X-33 program, multiple aerospike engine modules would be installed side by side on the vehicle. Seals are required in between adjacent engine modules along the edges and base of the engines. The seals have to withstand the extreme temperatures produced byt he thrusters at the top of the ramps while accommodating large deflections between adjacent ramps. We came up with several promising seal concepts for this application and shared them with Rocketdyne.
A Brush Seals Program Modeling and Developments
NASA Technical Reports Server (NTRS)
Hendricks, Robert C.; Flower, Ralph; Howe, Harold
1996-01-01
Some events of a U.S. Army/NASA Lewis Research Center brush seals program are reviewed, and the development of ceramic brush seals is described. Some preliminary room-temperature flow data are modeled and compare favorably to the results of Ergun.
ERIC Educational Resources Information Center
Collier, Herbert I.
1978-01-01
Energy conservation programs at Louisiana State University reduced energy use 23 percent. The programs involved computer controlled power management systems, adjustment of building temperatures and lighting levels to prescribed standards, consolidation of night classes, centralization of chilled water systems, and manual monitoring of heating and…
A test program was performed at the Environmental Protection Agency Incineration Research Facility to study the effectiveness of incineration at low-to-moderate temperatures in decontaminating soils containing organic compounds with different volatilities (boiling points). The da...
STREAM TEMPERATURE SIMULATION OF FORESTED RIPARIAN AREAS: II. MODEL APPLICATION
The SHADE-HSPF modeling system described in a companion paper has been tested and applied to the Upper Grande Ronde (UGR) watershed in northeast Oregon. Sensitivities of stream temperature to the heat balance parameters in Hydrologic Simulation Program-FORTRAN (HSPF) and the ripa...
Fatigue behavior of AAR Class A railroad wheel steel at ambient and elevated temperatures.
DOT National Transportation Integrated Search
2006-12-01
This report documents a test program to determine the material properties (chemical composition, tensile, and fatigue) at ambient and elevated temperatures of a Class A wheel steel as designated by the Association of American Railroads. The 3 tempera...
Buchanan, P.A.
2005-01-01
This article presents time-series graphs of specificconductance and water-temperature data collected in San Francisco Bay during water year 2004 (October 1, 2003, through September 30, 2004). Specific-conductance and water-temperature data were recorded at 15-minute intervals at seven U.S. Geological Survey (USGS) locations (Figure 1, Table 1). Specific-conductance and water-temperature data from Point San Pablo (PSP) and San Mateo Bridge (SMB) were recorded by the California Department of Water Resources (DWR) before 1988, by the USGS National Research Program from 1988 to 1989, and by the USGSDWR cooperative program since 1990. Benicia Bridge (BEN), Carquinez Bridge (CARQ), and Napa River (NAP) were established in 1998 by the USGS. San Pablo Bay (SPB) was initially established in 1998 at Channel Marker 9 but was moved to Channel Marker 1 in 2003. The monitoring station at Alcatraz (ALC) was established in 2003 by the USGS to replace the discontinued monitoring station San Francisco Bay at Presidio Military Reservation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wagstaff, N.; Prins, R.
1979-10-15
Temperature-programmed reduction has been used to characterize the finely dispersed metal compounds in a series of Pt-Re/..gamma..-Al/sub 2/O/sub 3/ catalysts. Strong evidence has been obtained that zerovalent Pt and Re atoms are in intimate contact with each other after catalyst reduction. The formation of bimetallic clusters supports the alloy explanation for the improved performance of this type of bimetallic reforming catalyst. Treatment of the reduced catalysts with oxygen above about 200/sup 0/C causes segregation of platinum and rhenium oxides. Adsorption of oxygen at temperatures up to 100/sup 0/C leaves the bimetallic clusters largely intact, but subsequent high-temperature treatment in themore » absence of extra oxygen leads to segregation of Pt and Re species. This suggests that in the presence of adsorbed oxygen the Pt-Re clusters are thermodynamically unstable, but that under mild conditions the rate of segregation is slow. 10 figures, 4 tables.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1978-02-01
The overall objective of this program is to assess and develop nondestructive evaluation procedures for high-temperature ceramics. The program is currently evaluating ceramic heat-exchanger tubing. Ceramic heat exchangers would be useful, for example, in coal-fired Brayton conversion or waste heat-recovery systems. The use of ceramic heat exchangers will allow working fluids to reach temperatures up to 1230/sup 0/C, and, with further materials development, possibly 1650/sup 0/C. If superalloys were employed, working fluids would be limited to approximately 800/sup 0/C. The use of working fluids at higher temperatures would result in more efficient systems. Furthermore, ceramic components are lighter than metallicmore » ones and are made from less costly and more abundant elements. In addition, ceramic heat exchangers would be more resistant to corrosion. In the current NDE effort, several acoustic, optical, and radiographic techniques are being examined for their effectiveness in testing silicon carbide tubing. Some results employing dye-enhanced radiography are discussed.« less
Broad area quantum cascade lasers operating in pulsed mode above 100 °C λ ∼4.7 μm
NASA Astrophysics Data System (ADS)
Zhao, Yue; Yan, Fangliang; Zhang, Jinchuan; Liu, Fengqi; Zhuo, Ning; Liu, Junqi; Wang, Lijun; Wang, Zhanguo
2017-07-01
We demonstrate a broad area (400 μm) high power quantum cascade laser (QCL). A total peak power of 62 W operating at room temperature is achieved at λ ∼4.7 μm. The temperature dependence of the peak power characteristic is given in the experiment, and also the temperature of the active zone is simulated by a finite-element-method (FEM). We find that the interface roughness of the active core has a great effect on the temperature of the active zone and can be enormously improved using the solid source molecular beam epitaxy (MBE) growth system. Project supported by the National Basic Research Program of China (No. 2013CB632801), the National Key Research and Development Program (No. 2016YFB0402303), the National Natural Science Foundation of China (Nos. 61435014, 61627822, 61574136, 61306058, 61404131), the Key Projects of Chinese Academy of Sciences (No. ZDRW-XH-20164), and the Beijing Natural Science Foundation (No. 4162060).
NASA Astrophysics Data System (ADS)
Maguire, J. F.; Yuan, J.
2009-10-01
This paper will describe the status of three key programs currently underway at American Superconductor Corp. The first program is the LIPA project which is a transmission voltage high temperature superconducting cable program, with funding support from the US Department of Energy. The 600 m cable, capable of carrying 574 MVA, was successfully installed and commissioned in LIPA grid on April 22, 2008. An overview of the project, system level design details and operational data will be provided. In addition, the status of the newly awarded LIPA II project will be described. The second program is Project Hydra, with funding support from the US Department of Homeland Security, to design, develop and demonstrate an HTS cable with fault current limiting functionality. The cable is 300 m long and is being designed to carry 96 MVA at a distribution level voltage of 13.8 kV. The cable will be permanently installed and energized in Manhattan, New York in 2010. The initial status of Project Hydra will be presented. The final program to be discussed is a transmission voltage, high temperature superconducting fault current limiter funded by the US DOE. The project encompasses the design, construction and test of a 115 kV FCL for power transmission within a time frame of 4-5 years. Installation and testing are planned for a Southern California Edison substation. A project overview and progress under the first phase will be reported.
History of HTS motor development at Reliance Electric
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schiferl, R.
1994-07-29
A review of the High Temperature Superconducting (HTS) motor development program at Reliance Electric is presented. The project was initiated in 1987 by EPRI to investigate the use of high temperature superconducting materials in electric motors. Liquid nitrogen was proposed as the HTS winding coolant. The ultimate goal, motivation, motor type and HTS wire requirements as well as the program milestones are outlined. It was concluded that the HTS motor development has paralleled wire development; progress continues toward the goal of large horsepower HTS motors for commercial applications; the team is well on the way toward completing the design ofmore » a 125 hp, 1800 rpm motor with HTS coils cooled to 20 to 40 K; and the program is a vital step in the development of HTS motors.« less
NASA Technical Reports Server (NTRS)
Gregory, G. L.; Beck, S. M.; Mathis, J. J., Jr.
1981-01-01
In situ correlative measurements were obtained with a NASA aircraft in support of two NASA airborne remote sensors participating in the Environmental Protection Agency's 1980persistent elevated pollution episode (PEPE) and Northeast regional oxidant study (NEROS) field program in order to provide data for evaluating the capability of two remote sensors for measuring mixing layer height, and ozone and aerosol concentrations in the troposphere during the 1980 PEPE/NEROS program. The in situ aircraft was instrumented to measure temperature, dewpoint temperature, ozone concentrations, and light scattering coefficient. In situ measurements for ten correlative missions are given and discussed. Each data set is presented in graphical and tabular format aircraft flight plans are included.
Thermal performance of MSFC hot air collectors under natural and simulated conditions
NASA Technical Reports Server (NTRS)
Shih, K., Sr.
1977-01-01
The procedures used and the results obtained from an evaluation test program conducted to determine the thermal performance and structural characteristics of selected MSFC--designed hot air collectors under both real and simulated environmental conditions are described. Five collectors were tested in the three phased program. A series of outdoor tests were conducted to determine stagnation temperatures on a typical bright day and to determine each collector's ability to withstand these temperatures. Two of the collectors experienced structural deformation sufficient to eliminate them from the remainder of the test program. A series of outdoor tests to evaluate the thermal performance of collector S/N 10 under certain test conditions were performed followed by a series of indoor tests to evaluate the thermal performance of the collector under closely controlled simulated conditions.
Giegold, Sascha; Teutenberg, Thorsten; Tuerk, Jochen; Kiffmeyer, Thekla; Wenclawiak, Bernd
2008-10-01
A fast HPLC method for the analysis of eight selected sulfonamides (SA) and trimethoprim has been developed with the use of high temperature HPLC. The separation could be achieved in less than 1.5 min on a 50 mm sub 2 microm column with simultaneous solvent and temperature gradient programming. Due to the lower viscosity of the mobile phase and the increased mass transfer at higher temperatures, the separation could be performed on a conventional HPLC system obtaining peak widths at half height between 0.6 and 1.3 s.
Computer program for pulsed thermocouples with corrections for radiation effects
NASA Technical Reports Server (NTRS)
Will, H. A.
1981-01-01
A pulsed thermocouple was used for measuring gas temperatures above the melting point of common thermocouples. This was done by allowing the thermocouple to heat until it approaches its melting point and then turning on the protective cooling gas. This method required a computer to extrapolate the thermocouple data to the higher gas temperatures. A method that includes the effect of radiation in the extrapolation is described. Computations of gas temperature are provided, along with the estimate of the final thermocouple wire temperature. Results from tests on high temperature combustor research rigs are presented.
Insects in fluctuating thermal environments.
Colinet, Hervé; Sinclair, Brent J; Vernon, Philippe; Renault, David
2015-01-07
All climate change scenarios predict an increase in both global temperature means and the magnitude of seasonal and diel temperature variation. The nonlinear relationship between temperature and biological processes means that fluctuating temperatures lead to physiological, life history, and ecological consequences for ectothermic insects that diverge from those predicted from constant temperatures. Fluctuating temperatures that remain within permissive temperature ranges generally improve performance. By contrast, those which extend to stressful temperatures may have either positive impacts, allowing repair of damage accrued during exposure to thermal extremes, or negative impacts from cumulative damage during successive exposures. We discuss the mechanisms underlying these differing effects. Fluctuating temperatures could be used to enhance or weaken insects in applied rearing programs, and any prediction of insect performance in the field-including models of climate change or population performance-must account for the effect of fluctuating temperatures.
NASA Astrophysics Data System (ADS)
Xin, Wang; Jiexing, Lin; Xiaozhou, Liu; Jiehui, Liu; Xiufen, Gong
2016-04-01
We used the spheroidal beam equation to calculate the sound field created by focusing a transducer with a wide aperture angle to obtain the heat deposition, and then we used the Pennes bioheat equation to calculate the temperature field in biological tissue with ribs and to ascertain the effects of rib parameters on the temperature field. The results show that the location and the gap width between the ribs have a great influence on the axial and radial temperature rise of multilayer biological tissue. With a decreasing gap width, the location of the maximum temperature rise moves forward; as the ribs are closer to the transducer surface, the sound energy that passes through the gap between the ribs at the focus decreases, the maximum temperature rise decreases, and the location of the maximum temperature rise moves forward with the ribs. Project supported by the National Basic Research Program of China (Grant Nos. 2012CB921504 and 2011CB707902), the National Natural Science Foundation of China (Grant No. 11274166), the Fundamental Research Funds for the Central Universities, China (Grant No. 020414380001), the Fund from State Key Laboratory of Acoustics, Chinese Academy of Sciences (Grant No. SKLA201401), China Postdoctoral Science Foundation (Grant No. 2013M531313), and the Priority Academic Program Development of Jiangsu Higher Education Institutions and SRF for ROCS, SEM.
Verification of the Multi-Axial, Temperature and Time Dependent (MATT) Failure Criterion
NASA Technical Reports Server (NTRS)
Richardson, David E.; Macon, David J.
2005-01-01
An extensive test and analytical effort has been completed by the Space Shuttle's Reusable Solid Rocket Motor (KSKM) nozzle program to characterize the failure behavior of two epoxy adhesives (TIGA 321 and EA946). As part of this effort, a general failure model, the "Multi-Axial, Temperature, and Time Dependent" or MATT failure criterion was developed. In the initial development of this failure criterion, tests were conducted to provide validation of the theory under a wide range of test conditions. The purpose of this paper is to present additional verification of the MATT failure criterion, under new loading conditions for the adhesives TIGA 321 and EA946. In many cases, the loading conditions involve an extrapolation from the conditions under which the material models were originally developed. Testing was conducted using three loading conditions: multi-axial tension, torsional shear, and non-uniform tension in a bondline condition. Tests were conducted at constant and cyclic loading rates ranging over four orders of magnitude. Tests were conducted under environmental conditions of primary interest to the RSRM program. The temperature range was not extreme, but the loading ranges were extreme (varying by four orders of magnitude). It should be noted that the testing was conducted at temperatures below the glass transition temperature of the TIGA 321 adhesive. However for the EA946, the testing was conducted at temperatures that bracketed the glass transition temperature.
ORNL superconducting technology program for electric power systems
NASA Astrophysics Data System (ADS)
Hawsey, R. A.
1994-04-01
The Oak Ridge National Laboratory (ORNL) Superconducting Technology Program is conducted as part of a national effort by the US Department of Energy's Office of Energy Efficiency and Renewable Energy to develop the technology base needed by US industry for commercial development of electric power applications of high-temperature superconductivity. The two major elements of this program are conductor development and applications development. This document describes the major research and development activities for this program together with related accomplishments. The technical progress reported was summarized from information prepared for the FY 1993 Annual Program Review held July 28--29, 1993. This ORNL program is highly leveraged by the staff and other resources of US industry and universities. In fact, nearly three-fourths of the ORNL effort is devoted to industrial competitiveness projects with private companies. Interlaboratory teams are also in place on a number of industry-driven projects. Patent disclosures, working group meetings, staff exchanges, and joint publications and presentations ensure that there is technology transfer to US industry. Working together, the collaborative teams are making rapid progress in solving the scientific and technical issues necessary for the commercialization of long lengths of practical high-temperature superconductor wire and wire products.
ORNL superconducting technology program for electric energy systems
NASA Astrophysics Data System (ADS)
Hawsey, R. A.
1993-02-01
The Oak Ridge National Laboratory (ORNL) Superconducting Technology Program is conducted as part of a national effort by the US Department of Energy's (DOE's) Office of Conservation and Renewable Energy to develop the technology base needed by US industry for commercial development of electric power applications of high-temperature superconductivity. The two major elements of this program are wire development and systems development. This document describes the major research and development activities for this program together with related accomplishments. The technical progress reported was summarized from information prepared for the FY-92 Peer Review of Projects, which was conducted by DOE's Office of Program Analysis, Office of Energy Research. This ORNL program is highly leveraged by the staff and other resources of US industry and universities. Interlaboratory teams are also in place on a number of industry-driven projects. Patent disclosures, working group meetings, staff exchanges, and joint publications and presentations ensure that there is technology transfer to US industry. Working together, the collaborative teams are making tremendous progress in solving the scientific and technical issues necessary for the commercialization of long lengths of practical high-temperature superconductor wire and wire products.
NASA Technical Reports Server (NTRS)
Liew, K. H.; Urip, E.; Yang, S. L.; Marek, C. J.
2004-01-01
Droplet interaction with a high temperature gaseous crossflow is important because of its wide application in systems involving two phase mixing such as in combustion requiring quick mixing of fuel and air with the reduction of pollutants and for jet mixing in the dilution zone of combustors. Therefore, the focus of this work is to investigate dispersion of a two-dimensional atomized and evaporating spray jet into a two-dimensional crossflow. An interactive Microsoft Excel program for tracking a single droplet in crossflow that has previously been developed will be modified to include droplet evaporation computation. In addition to the high velocity airflow, the injected droplets are also subjected to combustor temperature and pressure that affect their motion in the flow field. Six ordinary differential equations are then solved by 4th-order Runge-Kutta method using Microsoft Excel software. Microsoft Visual Basic programming and Microsoft Excel macrocode are used to produce the data and plot graphs describing the droplet's motion in the flow field. This program computes and plots the data sequentially without forcing the user to open other types of plotting programs. A user's manual on how to use the program is included.
Life prediction and constitutive models for engine hot section anisotropic materials program
NASA Technical Reports Server (NTRS)
Nissley, D. M.; Meyer, T. G.; Walker, K. P.
1992-01-01
This report presents a summary of results from a 7 year program designed to develop generic constitutive and life prediction approaches and models for nickel-based single crystal gas turbine airfoils. The program was composed of a base program and an optional program. The base program addressed the high temperature coated single crystal regime above the airfoil root platform. The optional program investigated the low temperature uncoated single crystal regime below the airfoil root platform including the notched conditions of the airfoil attachment. Both base and option programs involved experimental and analytical efforts. Results from uniaxial constitutive and fatigue life experiments of coated and uncoated PWA 1480 single crystal material formed the basis for the analytical modeling effort. Four single crystal primary orientations were used in the experiments: group of zone axes (001), group of zone axes (011), group of zone axes (111), and group of zone axes (213). Specific secondary orientations were also selected for the notched experiments in the optional program. Constitutive models for an overlay coating and PWA 1480 single crystal materials were developed based on isothermal hysteresis loop data and verified using thermomechanical (TMF) hysteresis loop data. A fatigue life approach and life models were developed for TMF crack initiation of coated PWA 1480. A life model was developed for smooth and notched fatigue in the option program. Finally, computer software incorporating the overlay coating and PWA 1480 constitutive and life models was developed.
J.A. Andresen; D.G. McCullough; B.E. Potter; C.N. Koller; L.S. Bauer; C. W. Ramm
2001-01-01
Accurate prediction of winter survival of gypsy moth (Lymantria dispar L.) eggs and phenology of egg hatch in spring are strongly dependent on temperature and are critical aspects of gypsy moth management programs. We monitored internal temperatures of egg masses at three heights aboveground level and at the four cardinal aspects on oak tree stems at two different...
Topoclimatological survey of Switzerland
NASA Technical Reports Server (NTRS)
Winiger, M. (Principal Investigator)
1982-01-01
The application of Heat Capacity Mapping Mission data to subsynoptic climate analysis of Switzerland was examined. The data included the surface temperature distributions of urban heat islands and the Swiss Alps. Analog and digital data evaluation procedures are described as well as the ground truth acquisition and comparison program. The dependence of the temperature distributions on topography and surface coverage types is assessed. The results indicate that air temperature inversion zones are detectable.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piyush Sabharwall; Matt Ebner; Manohar Sohal
2010-03-01
Considerable amount of work is going on regarding the development of high temperature liquid salts technology to meet future process needs of Next Generation Nuclear Plant. This report identifies the important characteristics and concerns of high temperature molten salts (with lesson learned at University of Wisconsin-Madison, Molten Salt Program) and provides some possible recommendation for future work
X-ray metal film filters at cryogenic temperatures
NASA Technical Reports Server (NTRS)
Keski-Kuha, Ritva A. M.
1989-01-01
Thin aluminum foil filters have been evaluated at cryogenic temperatures. The results of the test program, including cold cycling and vibration testing, indicate that these filters are fully successful at cryogenic temperatures and can provide the high X-ray transmittance and high background rejection required for the blocking filters which are being developed for the X-Ray Spectrometer, one of the focal plane instruments on the Advanced X-Ray Astrophysics Facility.
NASA Technical Reports Server (NTRS)
Wardwell, Douglas A.; Corsiglia, Victor R.; Kuhn, Richard E.
1992-01-01
NASA Ames Research Center has been conducting a program to improve the methods for predicting the jet-induced lift loss (suckdown) and hot gas ingestion on jet Short Takeoff and Vertical Landing (STOVL) aircraft during hover near the ground. As part of that program, small-scale hover tests were conducted to expand the current data base and to improve upon the current empirical methods for predicting jet-induced lift loss and hot gas ingestion (HGI) effects. This report is one of three data reports covering data obtained from hover tests conducted at Lockheed Aeronautical Systems, Rye Canyon Facility. It will include dynamic (time dependent) test data for both lift loss and HGI parameters (height, nozzle temperature, nozzle pressure ratio, and inlet location). The flat plate models tested were tandem jet configurations with three planform variations and variable position side-by-side sucking inlets mounted above the planform. Temperature time lags from 8-15 seconds were observed before the model temperatures stabilize. This was larger than the expected 1.5-second lag calculated from literature. Several possible explanations for the flow temperatures to stabilize may include some, or all, of the following: thermocouple lag, radiation to the model surface, and heat loss to the ground board. Further investigations are required to understand the reasons for this temperature lag.
Residential Indoor Temperature Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Booten, Chuck; Robertson, Joseph; Christensen, Dane
2017-04-07
In this study, we are adding to the body of knowledge around answering the question: What are good assumptions for HVAC set points in U.S. homes? We collected and analyzed indoor temperature data from US homes using funding from the U.S. Department of Energy's Building America (BA) program, due to the program's reliance on accurate energy simulation of homes. Simulations are used to set Building America goals, predict the impact of new building techniques and technologies, inform research objectives, evaluate home performance, optimize efficiency packages to meet savings goals, customize savings approaches to specific climate zones, and myriad other uses.
An interactive computer code for calculation of gas-phase chemical equilibrium (EQLBRM)
NASA Technical Reports Server (NTRS)
Pratt, B. S.; Pratt, D. T.
1984-01-01
A user friendly, menu driven, interactive computer program known as EQLBRM which calculates the adiabatic equilibrium temperature and product composition resulting from the combustion of hydrocarbon fuels with air, at specified constant pressure and enthalpy is discussed. The program is developed primarily as an instructional tool to be run on small computers to allow the user to economically and efficiency explore the effects of varying fuel type, air/fuel ratio, inlet air and/or fuel temperature, and operating pressure on the performance of continuous combustion devices such as gas turbine combustors, Stirling engine burners, and power generation furnaces.
Carbide fuel pin and capsule design for irradiations at thermionic temperatures
NASA Technical Reports Server (NTRS)
Siegel, B. L.; Slaby, J. G.; Mattson, W. F.; Dilanni, D. C.
1973-01-01
The design of a capsule assembly to evaluate tungsten-emitter - carbide-fuel combinations for thermionic fuel elements is presented. An inpile fuel pin evaluation program concerned with clad temperture, neutron spectrum, carbide fuel composition, fuel geometry,fuel density, and clad thickness is discussed. The capsule design was a compromise involving considerations between heat transfer, instrumentation, materials compatibility, and test location. Heat-transfer calculations were instrumental in determining the method of support of the fuel pin to minimize axial temperature variations. The capsule design was easily fabricable and utilized existing state-of-the-art experience from previous programs.
Thermophysical properties of Helium-4 from 0.8 to 1500 K with pressures to 2000 MPa
NASA Technical Reports Server (NTRS)
Arp, Vincent D.; Mccarty, Robert D.
1989-01-01
Tabular summary data of the thermophysical properties of fluid helium are given for temperatures from 0.8 to 1500 K, with pressures to 2000 MPa between 75 and 300 K, or to 100 MPa outside of this temperature band. Properties include density, specific heats, enthalpy, entropy, internal energy, sound velocity, expansivity, compressibility, thermal conductivity, and viscosity. The data are calculated from a computer program which is available from the National Institute of Standards and Technology. The computer program is based on carefully fitted state equations for both normal and superfluid helium.
1984-01-01
from the north, thereby occasionally encouraging unseasonably warm temperatures. Unseasonably cold temperatures most often occur when the Bermuda...marl. Hawthorn 160 - Sandy phophatic marl and soft limestone with interbedded brittle -shale. 25 OLIGOCENE (Ta) Flint River 50 - Reddish-yellow sand
Cold Weather Protection for Seed. Science Study Aid No. 6.
ERIC Educational Resources Information Center
Valieant, Joan A.
This science study aid, published by the U. S. Department of Agriculture and intended as a supplement to the regular science program, lists activities and experiments relating seed germination to various temperature changes and exposure to adverse temperature conditions for varying lengths of time. (CP)
40 CFR 86.246-94 - Intermediate temperature testing.
Code of Federal Regulations, 2010 CFR
2010-07-01
... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1994 and Later Model Year Gasoline-Fueled New Light-Duty Vehicles, New Light-Duty Trucks and New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.246-94 Intermediate...
Piston Temperatures in an Air-Cooled Engine for Various Operating Conditions
NASA Technical Reports Server (NTRS)
Manganiello, Eugene J
1940-01-01
As part of a program for the study of piston cooling, this report presents the results of tests conducted on a single-cylinder, air-cooled, carburetor engine to determine the effect of engine operating conditions on the temperatures at five locations on the piston.
Analyzing Flows In Rocket Nuclear Reactors
NASA Technical Reports Server (NTRS)
Clark, J. S.; Walton, J. T.; Mcguire, M.
1994-01-01
CAC is analytical prediction program to study heat-transfer and fluid-flow characteristics of circular coolant passage. Predicts, as function of time, axial and radial fluid conditions, temperatures of passage walls, rates of flow in each coolant passage, and approximate maximum material temperatures. Written in ANSI standard FORTRAN 77.
The field analytical screening program (FASP) polychlorinated biphenyl (PCB) method uses a temperature-programmable gas chromatograph (GC) equipped with an electron capture detector (ECD) to identify and quantify PCBs. Gas chromatography is an EPA-approved method for determi...
2014-01-01
program officer of ONR’s Computational Neuro - science and Biorobotics programs. “The goal of this research is to develop the mutual interaction between...water temperature, and transmitted this data to my office every five minutes. The entire buoy including the radio transmitter was powered by the BMFC
2002 NASA Seal/Secondary Air System Workshop. Volume 1
NASA Technical Reports Server (NTRS)
Steinetz, Bruce M. (Editor); Hendricks, Robert C. (Editor)
2003-01-01
The 2002 NASA Seal/Secondary Air System Workshop covered the following topics: (i) Overview of NASA s perspective of aeronautics and space technology for the 21st century; (ii) Overview of the NASA-sponsored Ultra-Efficient Engine Technology (UEET), Turbine-Based Combined-Cycle (TBCC), and Revolutionary Turbine Accelator (RTA) programs; (iii) Overview of NASA Glenn's seal program aimed at developing advanced seals for NASA's turbomachinery, space propulsion, and reentry vehicle needs; (iv) Reviews of sealing concepts, test results, experimental facilities, and numerical predictions; and (v) Reviews of material development programs relevant to advanced seals development. The NASA UEET and TBCC/RTA program overviews illustrated for the reader the importance of advanced technologies, including seals, in meeting future turbine engine system efficiency and emission goals. For example, the NASA UEET program goals include an 8- to 15-percent reduction in fuel burn, a 15-percent reduction in CO2, a 70-percent reduction in NOx, CO, and unburned hydrocarbons, and a 30-dB noise reduction relative to program baselines. The workshop also covered several programs NASA is funding to investigate advanced reusable space vehicle technologies (X-38) and advanced space ram/scramjet propulsion systems. Seal challenges posed by these advanced systems include high-temperature operation, resiliency at the operating temperature to accommodate sidewall flexing, and durability to last many missions.
NASA Technical Reports Server (NTRS)
Arya, Vinod K.; Halford, Gary R. (Technical Monitor)
2003-01-01
This manual presents computer programs FLAPS for characterizing and predicting fatigue and creep-fatigue resistance of metallic materials in the high-temperature, long-life regime for isothermal and nonisothermal fatigue. The programs use the Total Strain version of Strainrange Partitioning (TS-SRP), and several other life prediction methods described in this manual. The user should be thoroughly familiar with the TS-SRP and these life prediction methods before attempting to use any of these programs. Improper understanding can lead to incorrect use of the method and erroneous life predictions. An extensive database has also been developed in a parallel effort. The database is probably the largest source of high-temperature, creep-fatigue test data available in the public domain and can be used with other life-prediction methods as well. This users' manual, software, and database are all in the public domain and can be obtained by contacting the author. The Compact Disk (CD) accompanying this manual contains an executable file for the FLAPS program, two datasets required for the example problems in the manual, and the creep-fatigue data in a format compatible with these programs.
Loop Heat Pipe Operation Using Heat Source Temperature for Set Point Control
NASA Technical Reports Server (NTRS)
Ku, Jentung; Paiva, Kleber; Mantelli, Marcia
2011-01-01
Loop heat pipes (LHPs) have been used for thermal control of several NASA and commercial orbiting spacecraft. The LHP operating temperature is governed by the saturation temperature of its compensation chamber (CC). Most LHPs use the CC temperature for feedback control of its operating temperature. There exists a thermal resistance between the heat source to be cooled by the LHP and the LHP's CC. Even if the CC set point temperature is controlled precisely, the heat source temperature will still vary with its heat output. For most applications, controlling the heat source temperature is of most interest. A logical question to ask is: "Can the heat source temperature be used for feedback control of the LHP operation?" A test program has been implemented to answer the above question. Objective is to investigate the LHP performance using the CC temperature and the heat source temperature for feedback control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pyun, J.J.; Majumdar, D.
The paper describes TEMPEST, a simple computer program for the temperature and pressure estimation of a boiling fuel-steel pool in an LMFBR core. The time scale of interest of this program is large, of the order of ten seconds. Further, the vigorous boiling in the pool will generate a large contact, and hence a large heat transfer between fuel and steel. The pool is assumed to be a uniform mixture of fuel and steel, and consequently vapor production is also assumed to be uniform throughout the pool. The pool is allowed to expand in volume if there is steel meltingmore » at the walls. In this program, the total mass of liquid and vapor fuel is always kept constant, but the total steel mass in the pool may change by steel wall melting. Because of a lack of clear understanding of the physical phenomena associated with the progression of a fuel-steel mixture at high temperature, various input options have been built-in to enable one to perform parametric studies. For example, the heat transfer from the pool to the surrounding steel structure may be controlled by input values for the heat transfer coefficients, or, the heat transfer may be calculated by a correlation obtained from the literature. Similarly, condensation of vapor on the top wall can be specified by input values of the condensation coefficient; the program can otherwise calculate condensation according to the non-equilibrium model predictions. Meltthrough rates of the surrounding steel walls can be specified by a fixed melt-rate or can be determined by a fraction of the heat loss that goes to steel-melting. The melted steel is raised to the pool temperature before it is joined with the pool material. Several applications of this program to various fuel-steel pools in the FFTF and the CRBR cores are discussed.« less
Testing of Compact Bolted Fasteners with Insulation and Friction-Enhanced Shims for NCSX
DOE Office of Scientific and Technical Information (OSTI.GOV)
L. E. Dudek, J.H. Chrzanowski, G. Gettelfinger, P. Heitzenroeder, S. Jurczynski, M. Viola and K. Freudenberg
The fastening of the National Compact Stellarator Experiment's (NCSX) modular coils presented a number of engineering and manufacturing challenges due to the high magnetic forces, need to control induced currents, tight tolerances and restrictive space envelope. A fastening method using high strength studs, jack nuts, insulating spacers, bushings and alumina coated shims was developed which met the requirements. A test program was conducted to verify the design. The tests included measurements of flatness of the spacers, determination of contact area, torque vs. tension of the studs and jack nuts, friction coefficient tests on the alumina and G-10 insulators, electrical tests,more » and tension relaxation tests due to temperature excursions from room temperature to liquid nitrogen temperatures. This paper will describe the design and the results of the test program.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spycher, Nicolas; Peiffer, Loic; Finsterle, Stefan
GeoT implements the multicomponent geothermometry method developed by Reed and Spycher (1984, Geochim. Cosmichim. Acta 46 513–528) into a stand-alone computer program, to ease the application of this method and to improve the prediction of geothermal reservoir temperatures using full and integrated chemical analyses of geothermal fluids. Reservoir temperatures are estimated from statistical analyses of mineral saturation indices computed as a function of temperature. The reconstruction of the deep geothermal fluid compositions, and geothermometry computations, are all implemented into the same computer program, allowing unknown or poorly constrained input parameters to be estimated by numerical optimization using existing parameter estimationmore » software, such as iTOUGH2, PEST, or UCODE. This integrated geothermometry approach presents advantages over classical geothermometers for fluids that have not fully equilibrated with reservoir minerals and/or that have been subject to processes such as dilution and gas loss.« less
Chandrasekaran, Sivapragasam; Sankararajan, Vanitha; Neelakandhan, Nampoothiri; Ram Kumar, Mahalakshmi
2017-11-04
This study, through extensive experiments and mathematical modeling, reveals that other than retention time and wastewater temperature (T w ), atmospheric parameters also play important role in the effective functioning of aquatic macrophyte-based treatment system. Duckweed species Lemna minor is considered in this study. It is observed that the combined effect of atmospheric temperature (T atm ), wind speed (U w ), and relative humidity (RH) can be reflected through one parameter, namely the "apparent temperature" (T a ). A total of eight different models are considered based on the combination of input parameters and the best mathematical model is arrived at which is validated through a new experimental set-up outside the modeling period. The validation results are highly encouraging. Genetic programming (GP)-based models are found to reveal deeper understandings of the wetland process.
NASA Technical Reports Server (NTRS)
Khonsari, M. M.
1983-01-01
Thermohydrodynamic effects in journal bearings operating under steady load in laminar regime are investigated. An analytical model for the finite and infinitely long journal bearings is formulated. The model includes correction factors for the cavitation effects in the unloaded region of the bearing and the mixing of the recirculating oil and supply oil at the oil inlet. A finite difference computer program is developed to numerically solve the governing equations of the continuity, Reynolds, energy, Laplace heat conduction, and a viscosity-temperature relation simultaneously. The program includes a numerical technique for obtaining an isothermal shaft temperature. The numerical results of temperature distribution and the heat effects on the bearing load carrying capacity agree closely with those of experimental findings. Several different sets of simpler boundary conditions for the energy equation are studied.
Lee, Sang Moon; Park, Kwang Hee; Kim, Sung Su; Kwon, Dong Wook; Hong, Sung Chang
2012-09-01
TiO2-supported manganese oxide catalysts formed using different calcination temperatures were prepared by using the wet-impregnation method and were investigated for their activity in the low-temperature selective catalytic reduction (SCR) of NO by NH3 with respect to the Mn valence and lattice oxygen behavior. The surface and bulk properties of these catalysts were examined using Brunauer-Emmett-Teller (BET) surface area, X-ray diffraction (XRD), temperature-programmed reduction (TPR), and temperature-programmed desorption (TPD). Catalysts prepared using lower calcination temperatures, which contained Mn4+ displayed high SCR activity at low temperatures and possessed several acid sites and active oxygen. The TPD analysis determined that the Brönsted and Lewis acid sites in the Mn/TiO2 catalysts were important for the low-temperature SCR at 80-160 and 200-350 degrees C, respectively. In addition, the available lattice oxygen was important for attaining high NO to NO2 oxidation at low temperatures. Recently, various Mn catalysts have been evaluated as SCR catalysts. However, there have been no studies on the relationship of adsorption and desorption properties and behavior of lattice oxygen according to the valence state for manganese oxides (MnO(x)). Therefore, in this study, the catalysts were prepared by the wet-impregnation method at different calcination temperatures in order to show the difference of manganese oxidation state. These catalysts were then characterized using various physicochemical techniques, including BET, XRD, TPR, and TPD, to understand the structure, oxidation state, redox properties, and adsorption and desorption properties of the Mn/TiO2 catalysts.
Gritti, Fabrice
2016-11-18
An new class of gradient liquid chromatography (GLC) is proposed and its performance is analyzed from a theoretical viewpoint. During the course of such gradients, both the solvent strength and the column temperature are simultaneously changed in time and space. The solvent and temperature gradients propagate along the chromatographic column at their own and independent linear velocity. This class of gradient is called combined solvent- and temperature-programmed gradient liquid chromatography (CST-GLC). The general expressions of the retention time, retention factor, and of the temporal peak width of the analytes at elution in CST-GLC are derived for linear solvent strength (LSS) retention models, modified van't Hoff retention behavior, linear and non-distorted solvent gradients, and for linear temperature gradients. In these conditions, the theory predicts that CST-GLC is equivalent to a unique and apparent dynamic solvent gradient. The apparent solvent gradient steepness is the sum of the solvent and temperature steepness. The apparent solvent linear velocity is the reciprocal of the steepness-averaged sum of the reciprocal of the actual solvent and temperature linear velocities. The advantage of CST-GLC over conventional GLC is demonstrated for the resolution of protein digests (peptide mapping) when applying smooth, retained, and linear acetonitrile gradients in combination with a linear temperature gradient (from 20°C to 90°C) using 300μm×150mm capillary columns packed with sub-2 μm particles. The benefit of CST-GLC is demonstrated when the temperature gradient propagates at the same velocity as the chromatographic speed. The experimental proof-of-concept for the realization of temperature ramps propagating at a finite and constant linear velocity is also briefly described. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhou, Ye; Han, Su-Ting; Xu, Zong-Xiang; Roy, V. A. L.
2013-02-01
The strain and temperature dependent memory effect of organic memory transistors on plastic substrates has been investigated under ambient conditions. The gold (Au) nanoparticle monolayer was prepared and embedded in an atomic layer deposited aluminum oxide (Al2O3) as the charge trapping layer. The devices exhibited low operation voltage, reliable memory characteristics and long data retention time. Experimental analysis of the programming and erasing behavior at various bending states showed the relationship between strain and charging capacity. Thermal-induced effects on these memory devices have also been analyzed. The mobility shows ~200% rise and the memory window increases from 1.48 V to 1.8 V when the temperature rises from 20 °C to 80 °C due to thermally activated transport. The retention capability of the devices decreases with the increased working temperature. Our findings provide a better understanding of flexible organic memory transistors under various operating temperatures and validate their applications in various areas such as temperature sensors, temperature memory or advanced electronic circuits. Furthermore, the low temperature processing procedures of the key elements (Au nanoparticle monolayer and Al2O3 dielectric layer) could be potentially integrated with large area flexible electronics.The strain and temperature dependent memory effect of organic memory transistors on plastic substrates has been investigated under ambient conditions. The gold (Au) nanoparticle monolayer was prepared and embedded in an atomic layer deposited aluminum oxide (Al2O3) as the charge trapping layer. The devices exhibited low operation voltage, reliable memory characteristics and long data retention time. Experimental analysis of the programming and erasing behavior at various bending states showed the relationship between strain and charging capacity. Thermal-induced effects on these memory devices have also been analyzed. The mobility shows ~200% rise and the memory window increases from 1.48 V to 1.8 V when the temperature rises from 20 °C to 80 °C due to thermally activated transport. The retention capability of the devices decreases with the increased working temperature. Our findings provide a better understanding of flexible organic memory transistors under various operating temperatures and validate their applications in various areas such as temperature sensors, temperature memory or advanced electronic circuits. Furthermore, the low temperature processing procedures of the key elements (Au nanoparticle monolayer and Al2O3 dielectric layer) could be potentially integrated with large area flexible electronics. Electronic supplementary information (ESI) available: UV-vis spectrum of Au nanoparticle aqueous solution, transfer characteristics of the transistors without inserting an Au nanoparticle monolayer, AFM image of the pentacene layer, transfer characteristics at different program voltages and memory windows with respect to the P/E voltage. See DOI: 10.1039/c2nr32579a
Design of a computerized, temperature-controlled, recirculating aquaria system
Widmer, A.M.; Carveth, C.J.; Keffler, J.W.; Bonar, Scott A.
2006-01-01
We built a recirculating aquaria system with computerized temperature control to maintain static temperatures, increase temperatures 1 ??C/day, and maintain diel temperature fluctuations up to 10 ??C. A LabVIEW program compared the temperature recorded by thermocouples in fish tanks to a desired set temperature and then calculated the amount of hot or cold water to add to tanks to reach or maintain the desired temperature. Intellifaucet?? three-way mixing valves controlled temperature of the input water and ensured that all fish tanks had the same turnover rate. The system was analyzed over a period of 50 days and was fully functional for 96% of that time. Six different temperature treatments were run simultaneously in 18, 72 L fish tanks and temperatures stayed within 0.5 ??C of set temperature. We used the system to determine the upper temperature tolerance of fishes, but it could be used in aquaculture, ecological studies, or other aquatic work where temperature control is required. ?? 2005 Elsevier B.V. All rights reserved.
Wu, Changzheng; Zhang, Xiaodong; Ning, Bo; Yang, Jinlong; Xie, Yi
2009-07-06
Solid templates have been long regarded as one of the most promising ways to achieve single-shelled hollow nanostructures; however, few effective methods for the construction of multishelled hollow objects from their solid template counterparts have been developed. We report here, for the first time, a novel and convenient route to synthesizing double-shelled hollow spheres from the solid templates via programming the reaction-temperature procedures. The programmed temperature strategy developed in this work then provides an essential and general access to multishelled hollow nanostructures based on the designed extension of single-shelled hollow objects, independent of their outside contours, such as tubes, hollow spheres, and cubes. Starting from the V(OH)(2)NH(2) solid templates, we show that the relationship between the hollowing rate and the reaction temperature obey the Van't Hoff rule and Arrhenius activation-energy equation, revealing that it is the chemical reaction rather than the diffusion process that guided the whole hollowing process, despite the fact that the coupled reaction/diffusion process is involved in the hollowing process. Using the double-shelled hollow spheres as the PCM (CaCl(2).6H(2)O) matrix grants much better thermal-storage stability than that for the nanoparticles counterpart, revealing that the designed nanostructures can give rise to significant improvements for the energy-saving performance in future "smart house" systems.
High-temperature Strain Sensor and Mounting Development
NASA Technical Reports Server (NTRS)
Williams, W. Dan; Lei, Jih-Fen; Reardon, Lawrence F.; Krake, Keith; Lemcoe, M. M.; Holmes, Harlan K.; Moore, Thomas C., Sr.
1996-01-01
This report describes Government Work Package Task 29 (GWP29), whose purpose was to develop advanced strain gage technology in support of the National Aerospace Plane (NASP) Program. The focus was on advanced resistance strain gages with a temperature range from room temperature to 2000 F (1095 C) and on methods for reliably attaching these gages to the various materials anticipated for use in the NASP program. Because the NASP program required first-cycle data, the installed gages were not prestabilized or heat treated on the test coupons before first-cycle data were recorded. NASA Lewis Research Center, the lead center for GWP29, continued its development of the palladium-chromium gage; NASA Langley Research Center investigated a new concept gage using Kanthal A1; and the NASA Dryden Flight Research Center chose the well-known BCL-3 iron-chromium-aluminum gage. Each center then tested all three gages. The parameters investigated were apparent strain, drift strain, and gage factor as a function of temperature, plus gage size and survival rate over the test period. Although a significant effort was made to minimize the differences in test equipment between the three test sites (e.g., the same hardware and software were used for final data processing), the center employed different data acquisition systems and furnace configurations so that some inherent differences may be evident in the final results.
Polyimide/Glass Composite High-Temperature Insulation
NASA Technical Reports Server (NTRS)
Pater, Ruth H.; Vasquez, Peter; Chatlin, Richard L.; Smith, Donald L.; Skalski, Thomas J.; Johnson, Gary S.; Chu, Sang-Hyon
2009-01-01
Lightweight composites of RP46 polyimide and glass fibers have been found to be useful as extraordinarily fire-resistant electrical-insulation materials. RP46 is a polyimide of the polymerization of monomeric reactants (PMR) type, developed by NASA Langley Research Center. RP46 has properties that make it attractive for use in electrical insulation at high temperatures. These properties include high-temperature resistance, low relative permittivity, low dissipation factor, outstanding mechanical properties, and excellent resistance to moisture and chemicals. Moreover, RP46 contains no halogen or other toxic materials and when burned it does not produce toxic fume or gaseous materials. The U. S. Navy has been seeking lightweight, high-temperature-resistant electrical-insulation materials in a program directed toward reducing fire hazards and weights in ship electrical systems. To satisfy the requirements of this program, an electrical-insulation material must withstand a 3-hour gas-flame test at 1,600 F (about 871 C). Prior to the development reported here, RP46 was rated for use at temperatures from -150 to +700 F (about -101 to 371 C), and no polymeric product - not even RP46 - was expected to withstand the Navy 3-hour gas-flame test.
NASA Technical Reports Server (NTRS)
Gille, J. P.
1972-01-01
A program is described that was conducted to develop an internal insulation system for potential application to the liquid hydrogen tanks of a reusable booster, where the tanks would be subjected to repeated high temperatures. The design of the internal insulation is based on a unique gas layer concept, in which capillary or surface tension effects are used to maintain a stable gas layer, within a cellular core structure, between the tank wall and the contained liquid hydrogen. Specific objectives were to select materials for insulation systems that would be compatible with wall temperatures of 350 F and 650 F during reentry into the earth's atmosphere, and to fabricate and test insulation systems under conditions simulating the operating environment. A materials test program was conducted to evaluate the properties of candidate materials at elevated temperatures and at the temperature of liquid hydrogen, and to determine the compatibility of the materials with a hydrogen atmosphere at the appropriate elevated temperature. The materials that were finally selected included Kapton polyimide films, silicone adhesives, fiber glass batting, and in the case of the 350 F system, Teflon film.
NASA Astrophysics Data System (ADS)
Wang, Lu; Zhang, Guo-Hua; Chou, Kuo-Chih
2017-10-01
In the present wok, single-crystalline spherical γ-Mo2N powders was successfully prepared by the temperature-programmed reaction of single-crystal spherical β-MoO3 with NH3 in the temperature ranges of 1013-1073 K. Herein, the Mo source used was monoclinic system, β-MoO3, a metastable phase of MoO3. It is found that the characterizations of the as-prepared γ-Mo2N powders are strongly depended on the selection of the MoO3 precursor. In other words, the as-prepared γ-Mo2N powders inherited the shape, size and structure of the used β-MoO3 precursors upon reaction with NH3. In order to make a comparison, β-MoO3 was also reduced by the mixed gases of N2 and H2 with the flow rate ratio of 1:3 at the identical conditions. It was found that pure β-Mo2N polycrystalline can be obtained when the temperature was 1013 K; while further increasing the reaction temperature, metal Mo powder will be turned up.
Thermalization, Freeze-out, and Noise: Deciphering Experimental Quantum Annealers
NASA Astrophysics Data System (ADS)
Marshall, Jeffrey; Rieffel, Eleanor G.; Hen, Itay
2017-12-01
By contrasting the performance of two quantum annealers operating at different temperatures, we address recent questions related to the role of temperature in these devices and their function as "Boltzmann samplers." Using a method to reliably calculate the degeneracies of the energy levels of large-scale spin-glass instances, we are able to estimate the instance-dependent effective temperature from the output of annealing runs. Our results corroborate the "freeze-out" picture which posits two regimes, one in which the final state corresponds to a Boltzmann distribution of the final Hamiltonian with a well-defined "effective temperature" determined at a freeze-out point late in the annealing schedule, and another regime in which such a distribution is not necessarily expected. We find that the output distributions of the annealers do not, in general, correspond to a classical Boltzmann distribution for the final Hamiltonian. We also find that the effective temperatures at different programing cycles fluctuate greatly, with the effect worsening with problem size. We discuss the implications of our results for the design of future quantum annealers to act as more-effective Boltzmann samplers and for the programing of such annealers.
Temperature histories of commercial flights at severe conditions from GASP data
NASA Technical Reports Server (NTRS)
Jasperson, W. H.; Nastrom, G. D.
1983-01-01
The thermal environment of commercial aircraft from a data set gathered during the Global Atmospheric Sampling Program (GASP) is studied. The data set covers a four-year period of measurements. The report presents plots of airplane location and speed and atmospheric temperature as functions of elapsed time for 35 extreme-condition flights, selected by minimum values of several temperature parameters. One of these parameters, the severity factor, is an approximation of the in-flight wing-tank temperature. Representative low-severity-factor flight histories may be useful for actual temperature-profile inputs to design and research studies. Comparison of the GASP atmospheric temperatures to interpolated temperatures from National Meteorological Center and Global Weather Central analysis fields shows that the analysis temperatures are slightly biased toward warmer than actual temperatures, particularly over oceans and at extreme conditions.
10 CFR 26.111 - Checking the acceptability of the urine specimen.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 1 2013-01-01 2013-01-01 false Checking the acceptability of the urine specimen. 26.111 Section 26.111 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Collecting Specimens for..., the collector shall measure the temperature of the specimen. The temperature-measuring device used...
10 CFR 26.111 - Checking the acceptability of the urine specimen.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 1 2012-01-01 2012-01-01 false Checking the acceptability of the urine specimen. 26.111 Section 26.111 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Collecting Specimens for..., the collector shall measure the temperature of the specimen. The temperature-measuring device used...
10 CFR 26.111 - Checking the acceptability of the urine specimen.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 1 2014-01-01 2014-01-01 false Checking the acceptability of the urine specimen. 26.111 Section 26.111 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Collecting Specimens for..., the collector shall measure the temperature of the specimen. The temperature-measuring device used...
USDA-ARS?s Scientific Manuscript database
Whey protein concentrate (WPC) has been recommended for use in emergency aid programs, but it is often stored overseas without temperature and relative humidity (RH) control, which may cause it to be rejected because of yellowing, off-flavors, or clumping. Therefore, the volatile compounds present ...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-10
.... Incomplete Cycling 6. Mechanical Temperature Controls 7. Ambient Temperature Gradient 8. Definitions.... at 29846-29847. A broad group of stakeholders \\1\\ submitted a joint comment supporting DOE's proposal... for variable defrost control (a control type in which the time interval between successive defrost...