What Is the Boiling Point and Heat of Vaporization of Sulfuric Acid?

ERIC Educational Resources Information Center

Myers, R. Thomas

1983-01-01

Discusses the values presented in various handbooks for the boiling point and heat of vaporization of sulfuric acid, noting discrepencies. Analyzes various approaches to data presentation, discussing the data on sulfuric acid in light of the Trouton constant. Points out the need for a more critical use of tables. (JM)

Direct production of fractionated and upgraded hydrocarbon fuels from biomass

DOEpatents

Felix, Larry G.; Linck, Martin B.; Marker, Terry L.; Roberts, Michael J.

2014-08-26

Multistage processing of biomass to produce at least two separate fungible fuel streams, one dominated by gasoline boiling-point range liquids and the other by diesel boiling-point range liquids. The processing involves hydrotreating the biomass to produce a hydrotreatment product including a deoxygenated hydrocarbon product of gasoline and diesel boiling materials, followed by separating each of the gasoline and diesel boiling materials from the hydrotreatment product and each other.

Cooking under Pressure: Applying the Ideal Gas Law in the Kitchen

ERIC Educational Resources Information Center

Chen, Ling; Anderson, Jennifer Y.; Wang, Diane R.

2010-01-01

This case study uses a daily cooking scenario to demonstrate how the boiling point of water is directly related to the external pressures in order to reinforce the concepts of boiling and boiling point, apply ideal gas law, and relate chemical reaction rates with temperatures. It also extends its teaching to autoclaves used to destroy…

Experimental evidence of the vapor recoil mechanism in the boiling crisis.

PubMed

Nikolayev, V S; Chatain, D; Garrabos, Y; Beysens, D

2006-11-03

Boiling crisis experiments are carried out in the vicinity of the liquid-gas critical point of H2. A magnetic gravity compensation setup is used to enable nucleate boiling at near critical pressure. The measurements of the critical heat flux that defines the threshold for the boiling crisis are carried out as a function of the distance from the critical point. The obtained power law behavior and the boiling crisis dynamics agree with the predictions of the vapor recoil mechanism and disagree with the classical vapor column mechanism.

The boiling point of stratospheric aerosols.

NASA Technical Reports Server (NTRS)

Rosen, J. M.

1971-01-01

A photoelectric particle counter was used for the measurement of aerosol boiling points. The operational principle involves raising the temperature of the aerosol by vigorously heating a portion of the intake tube. At or above the boiling point, the particles disintegrate rather quickly, and a noticeable effect on the size distribution and concentration is observed. Stratospheric aerosols appear to have the same volatility as a solution of 75% sulfuric acid. Chemical analysis of the aerosols indicates that there are other substances present, but that the sulfate radical is apparently the major constituent.

Nutrition content of brisket point end of part Simental Ongole Crossbred meat in boiled various temperature

NASA Astrophysics Data System (ADS)

Riyanto, J.; Sudibya; Cahyadi, M.; Aji, A. P.

2018-01-01

This aim of this study was to determine the quality of nutritional contents of beef brisket point end of Simental Ongole Crossbred meat in various boiling temperatures. Simental Ongole Crossbred had been fattened for 9 months. Furthermore, they were slaughtered at slaughterhouse and brisket point end part of meat had been prepared to analyse its nutritional contents using Food Scan. These samples were then boiled at 100°C for 0 (TR), 15 (R15), and 30 (R30) minutes, respectively. The data was analysed using Randomized Complete Design (CRD) and Duncan’s multiple range test (DMRT) had been conducted to differentiate among three treatments. The results showed that boiling temperatures significantly affected moisture, and cholesterol contents of beef (P<0.05) while fat content was not significantly affected by boiling temperatures. The boiling temperature decreased beef water contents from 72.77 to 70.84%, on the other hand, the treatment increased beef protein and cholesterol contents from 20.77 to 25.14% and 47.55 to 50.45 mg/100g samples, respectively. The conclusion of this study was boiling of beef at 100°C for 15 minutes and 30 minutes decreasing water content and increasing protein and cholesterol contents of brisket point end of Simental Ongole Crossbred beef.

The effect of vapor polarity and boiling point on breakthrough for binary mixtures on respirator carbon.

PubMed

Robbins, C A; Breysse, P N

1996-08-01

This research evaluated the effect of the polarity of a second vapor on the adsorption of a polar and a nonpolar vapor using the Wheeler model. To examine the effect of polarity, it was also necessary to observe the effect of component boiling point. The 1% breakthrough time (1% tb), kinetic adsorption capacity (W(e)), and rate constant (kv) of the Wheeler model were determined for vapor challenges on carbon beds for both p-xylene and pyrrole (referred to as test vapors) individually, and in equimolar binary mixtures with the polar and nonpolar vapors toluene, p-fluorotoluene, o-dichlorobenzene, and p-dichlorobenzene (referred to as probe vapors). Probe vapor polarity (0 to 2.5 Debye) did not systematically alter the 1% tb, W(e), or kv of the test vapors. The 1% tb and W(e) for test vapors in binary mixtures can be estimated reasonably well, using the Wheeler model, from single-vapor data (1% tb +/- 30%, W(e) +/- 20%). The test vapor 1% tb depended mainly on total vapor concentration in both single and binary systems. W(e) was proportional to test vapor fractional molar concentration (mole fraction) in mixtures. The kv for p-xylene was significantly different (p < or = 0.001) when compared according to probe boiling point; however, these differences were apparently of limited importance in estimating 1% tb for the range of boiling points tested (111 to 180 degrees C). Although the polarity and boiling point of chemicals in the range tested are not practically important in predicting 1% tb with the Wheeler model, an effect due to probe boiling point is suggested, and tests with chemicals of more widely ranging boiling point are warranted. Since the 1% tb, and thus, respirator service life, depends mainly on total vapor concentration, these data underscore the importance of taking into account the presence of other vapors when estimating respirator service life for a vapor in a mixture.

THE FREEZING POINT DEPRESSION OF MAMMALIAN TISSUES AFTER SUDDEN HEATING IN BOILING DISTILLED WATER

PubMed Central

Appelboom, Johannes W. Th.; Brodsky, William A.; Tuttle, William S.; Diamond, Israel

1958-01-01

The calculated freezing point depression of freshly excised boiled mammalian tissue is approximately the same as that of plasma. The boiling procedure was chosen to eliminate the influence of metabolism on the level of the freezing point depression. Problems created by the boiling, such as equilibrium between tissue and diluent, change in activity coefficient by dilution, and loss of CO2 content, are discussed. A frozen crushed tissue homogenate is hypertonic to plasma. Boiling and dilution of such hypertonic homogenate exposed to room temperature for 5 to 15 minutes did not produce significant or unexplicable decreases in its osmotic activity. Moreover, freezing and crushing of a boiled diluted tissue did not produce any increase of the isoosmotic level of freezing point depression. It is possible to explain these data either with the hypothesis of hypertonic cell fluid or with that of isotonic cell fluid. In the case of an assumed isotonic cell fluid, data can be explained with one assumption, experimentally backed. In the case of an assumed hypertonic theory data can be explained only with the help of at least three ad hoc postulates. The data support the validity of the classical concept which holds that cell fluid is isotonic to extracellular fluid. PMID:13563805

Prediction of boiling points of organic compounds by QSPR tools.

PubMed

Dai, Yi-min; Zhu, Zhi-ping; Cao, Zhong; Zhang, Yue-fei; Zeng, Ju-lan; Li, Xun

2013-07-01

The novel electro-negativity topological descriptors of YC, WC were derived from molecular structure by equilibrium electro-negativity of atom and relative bond length of molecule. The quantitative structure-property relationships (QSPR) between descriptors of YC, WC as well as path number parameter P3 and the normal boiling points of 80 alkanes, 65 unsaturated hydrocarbons and 70 alcohols were obtained separately. The high-quality prediction models were evidenced by coefficient of determination (R(2)), the standard error (S), average absolute errors (AAE) and predictive parameters (Qext(2),RCV(2),Rm(2)). According to the regression equations, the influences of the length of carbon backbone, the size, the degree of branching of a molecule and the role of functional groups on the normal boiling point were analyzed. Comparison results with reference models demonstrated that novel topological descriptors based on the equilibrium electro-negativity of atom and the relative bond length were useful molecular descriptors for predicting the normal boiling points of organic compounds. Copyright © 2013 Elsevier Inc. All rights reserved.

Group vector space method for estimating enthalpy of vaporization of organic compounds at the normal boiling point.

PubMed

Wenying, Wei; Jinyu, Han; Wen, Xu

2004-01-01

The specific position of a group in the molecule has been considered, and a group vector space method for estimating enthalpy of vaporization at the normal boiling point of organic compounds has been developed. Expression for enthalpy of vaporization Delta(vap)H(T(b)) has been established and numerical values of relative group parameters obtained. The average percent deviation of estimation of Delta(vap)H(T(b)) is 1.16, which show that the present method demonstrates significant improvement in applicability to predict the enthalpy of vaporization at the normal boiling point, compared the conventional group methods.

A Closer Look at Trends in Boiling Points of Hydrides: Using an Inquiry-Based Approach to Teach Intermolecular Forces of Attraction

ERIC Educational Resources Information Center

Glazier, Samantha; Marano, Nadia; Eisen, Laura

2010-01-01

We describe how we use boiling-point trends of group IV-VII hydrides to introduce intermolecular forces in our first-year general chemistry classes. Starting with the idea that molecules in the liquid state are held together by some kind of force that must be overcome for boiling to take place, students use data analysis and critical reasoning to…

Studying Intermolecular Forces with a Dual Gas Chromatography and Boiling Point Investigation

ERIC Educational Resources Information Center

Cunningham, William Patrick; Xia, Ian; Wickline, Kaitlyn; Huitron, Eric Ivan Garcia; Heo, Jun

2018-01-01

A procedure for the study of structural differences and intermolecular attraction between ethanol and 1-butanol based in laboratory work is described. This study provides comparisons of data retrieved from both a determination of boiling point and gas chromatography traces for the mixture. The methodology reported here should provide instructors…

Watching the Pot to Improve Inquiry Skills

ERIC Educational Resources Information Center

Brockway, Debra; Papaleo, Marie

2009-01-01

The International Boiling Point Project is an online, collaborative project for students in grades 6-12 in which they investigate the impact of four factors (room temperature, elevation, volume of water and heating device) on the boiling point of water. A detailed procedure is provided for students in order to limit the number of variables…

CONTINUOUS ANALYZER UTILIZING BOILING POINT DETERMINATION

DOEpatents

Pappas, W.S.

1963-03-19

A device is designed for continuously determining the boiling point of a mixture of liquids. The device comprises a distillation chamber for boiling a liquid; outlet conduit means for maintaining the liquid contents of said chamber at a constant level; a reflux condenser mounted above said distillation chamber; means for continuously introducing an incoming liquid sample into said reflux condenser and into intimate contact with vapors refluxing within said condenser; and means for measuring the temperature of the liquid flowing through said distillation chamber. (AEC)

Fecal contamination of drinking water within peri-urban households, Lima, Peru.

PubMed

Oswald, William E; Lescano, Andrés G; Bern, Caryn; Calderon, Maritza M; Cabrera, Lilia; Gilman, Robert H

2007-10-01

We assessed fecal contamination of drinking water in households in 2 peri-urban communities of Lima, Peru. We measured Escherichia coli counts in municipal source water and, within households, water from principal storage containers, stored boiled drinking water, and water in a serving cup. Source water was microbiologically clean, but 26 (28%) of 93 samples of water stored for cooking had fecal contamination. Twenty-seven (30%) of 91 stored boiled drinking water samples grew E. coli. Boiled water was more frequently contaminated when served in a drinking cup than when stored (P < 0.01). Post-source contamination increased successively through the steps of usage from source water to the point of consumption. Boiling failed to ensure safe drinking water at the point of consumption because of easily contaminated containers and poor domestic hygiene. Hygiene education, better point-of-use treatment and storage options, and in-house water connections are urgently needed.

Correlation of physical properties with molecular structure for some dicyclic hydrocarbons having high thermal-energy release per unit volume -- 2-alkylbiphenyl and the two isomeric 2-alkylbicyclohexyl series

NASA Technical Reports Server (NTRS)

Goodman, Irving A; Wise, Paul H

1952-01-01

Three homologous series of related dicyclic hydrocarbons are presented for comparison on the basis of their physical properties, which include net heat of combustion, density, melting point, boiling point, and kinematic viscosity. The three series investigated include the 2-n-alkylbiphenyl, 2-n-alkylbicyclohexyl (high boiling), and 2-n-alkylbiphenyls (low boiling) series through c sub 16, in addition to three branched-chain (isopropyl, sec-butyl, and isobutyl) 2-alkylbiphenyls and their corresponding 2-alkylbicyclohexyls. The physical properties of the low-boiling and high-boiling isomers of 2-sec-butylbicyclohexyl and 2-isobutylbicyclohexyl are reported herein for the first time.

Determination of the Latent Heats and Triple Point of Perfluorocyclobutane

ERIC Educational Resources Information Center

Briggs, A. G.; Strachan, A. N.

1977-01-01

Proposes the use of Perfluorocyclobutane in physical chemistry courses to conduct experiments on latent heat, triple point temperatures and pressures, boiling points, and entropy of vaporization. (SL)

[Intersection point rule for the retention value with mobile phase composition and boiling point of the homologues and chlorobenzenes in soil leaching column chromatography].

PubMed

Xu, F; Liang, X; Lin, B; Su, F

1999-03-01

Based on the linear retention equation of the logarithm of the capacity factor (logk') vs. the methanol volume fraction (psi) of aqueous binary mobile phase in soil leaching column chromatography, the intersection point rule for the logk' of homologues and weak polar chlorobenzenes, with psi, as well as with boiling point, has been derived due to existence of the similar interactions among solutes of the same series, stationary phase (soil) and eluent (methanol-water). These rules were testified by experimental data of homologues (n-alkylbenzenes, methylbenzenes) and weak polar chlorobenzenes.

Explaining Melting and Evaporation below Boiling Point. Can Software Help with Particle Ideas?

ERIC Educational Resources Information Center

Papageorgiou, George; Johnson, Philip; Fotiades, Fotis

2008-01-01

This paper reports the findings of a study exploring the use of a software package to help pupils understand particulate explanations for melting and evaporation below boiling point. Two matched classes in a primary school in Greece (ages 11-12, n = 16 and 19) were involved in a short intervention of six one hour lessons. Covering the same…

Chemical Identity Crisis: Glass and Glassblowing in the Identification of Organic Compounds.

PubMed

Jackson, Catherine M

2015-04-01

This essay explains why and how nineteenth-century chemists sought to stabilize the melting and boiling points of organic substances as reliable characteristics of identity and purity and how, by the end of the century, they established these values as 'Constants of Nature'. Melting and boiling points as characteristic values emerge from this study as products of laboratory standardization, developed by chemists in their struggle to classify, understand and control organic nature. A major argument here concerns the role played by the introduction of organic synthesis in driving these changes. Synthetic organic chemistry vastly increased the number of known organic substances, precipitating the chemical identity crisis of my title. Successful natural product synthesis, moreover, depended on chemists' ability to demonstrate the absolute identity of synthetic product and natural target--something late nineteenth-century chemists eventually achieved by making reliable, replicable melting and boiling point measurements. In the period before the establishment of national standards laboratories, chemists and scientific glassblowers worked together to standardize melting and boiling points as physical constants, such collaborations highlighting the essential importance of chemical glassware and glassblowing skill in the development of nineteenth-century organic chemistry.

Method for hydrocracking a heavy polynuclear hydrocarbonaceous feedstock in the presence of a molten metal halide catalyst

DOEpatents

Gorin, Everett

1981-01-01

A method for hydrocracking a heavy polynuclear hydrocarbonaceous feedstock to produce lighter hydrocarbon fuels by contacting the feedstock with hydrogen in the presence of a molten metal halide catalyst, the method comprising: mixing the feedstock with a heavy naphtha fraction which has an initial boiling point from about 100.degree. to about 160.degree. C. with a boiling point difference between the initial boiling point and the final boiling point of no more than about 50.degree. C. to produce a mixture; thereafter contacting the mixture with partially spent molten metal halide and hydrogen under temperature and pressure conditions so that the temperature is near the critical temperature of the heavy naphtha fraction; separating at least a portion of the heavy naphtha fraction and lighter hydrocarbon fuels from the partially spent molten metal halide, unreacted feedstock and reaction products; thereafter contacting the partially spent molten metal halide, unreacted feedstock and reaction products with hydrogen and fresh molten metal halide in a hydrocracking zone to produce additional lighter hydrocarbon fuels and separating at least a major portion of the lighter hydrocarbon fuels from the spent molten metal halide.

On the critical temperature, normal boiling point, and vapor pressure of ionic liquids.

PubMed

Rebelo, Luis P N; Canongia Lopes, José N; Esperança, José M S S; Filipe, Eduardo

2005-04-07

One-stage, reduced-pressure distillations at moderate temperature of 1-decyl- and 1-dodecyl-3-methylimidazolium bistriflilamide ([Ntf(2)](-)) ionic liquids (ILs) have been performed. These liquid-vapor equilibria can be understood in light of predictions for normal boiling points of ILs. The predictions are based on experimental surface tension and density data, which are used to estimate the critical points of several ILs and their corresponding normal boiling temperatures. In contrast to the situation found for relatively unstable ILs at high-temperature such as those containing [BF(4)](-) or [PF(6)](-) anions, [Ntf(2)](-)-based ILs constitute a promising class in which reliable, accurate vapor pressure measurements can in principle be performed. This property is paramount for assisting in the development and testing of accurate molecular models.

Synthesis of PVP-stabilized ruthenium colloids with low boiling point alcohols.

PubMed

Zhang, Yuqing; Yu, Jiulong; Niu, Haijun; Liu, Hanfan

2007-09-15

A route to the preparation of poly(N-vinyl-2-pyrrolidone) (PVP)-stabilized ruthenium colloids by refluxing ruthenium(III) chloride in low boiling point alcohols was developed. Deep purple colloids with shuttle-like ruthenium particles were also synthesized. XPS measurement verified the nanoparticles were in the metallic state. The morphology of metal nanoparticles was characterized by UV-visible absorption spectrophotometry, TEM and XRD.

Takahasi Nearest-Neighbour Gas Revisited II: Morse Gases

NASA Astrophysics Data System (ADS)

Matsumoto, Akira

2011-12-01

Some thermodynamic quantities for the Morse potential are analytically evaluated at an isobaric process. The parameters of Morse gases for 21 substances are obtained by the second virial coefficient data and the spectroscopic data of diatomic molecules. Also some thermodynamic quantities for water are calculated numerically and drawn graphically. The inflexion point of the length L which depends on temperature T and pressure P corresponds physically to a boiling point. L indicates the liquid phase from lower temperature to the inflexion point and the gaseous phase from the inflexion point to higher temperature. The boiling temperatures indicate reasonable values compared with experimental data. The behaviour of L suggests a chance of a first-order phase transition in one dimension.

Comparison of carbon monoxide levels during heating of ice and water to boiling point with a camping stove.

PubMed

Leigh-Smith, Simon; Watt, Ian; McFadyen, Angus; Grant, Stan

2004-01-01

To determine whether using a camping stove to bring a pan of ice to boiling point produces higher carbon monoxide (CO) concentration than would bringing a pan of water to boiling point. The hypothesis was that ice would cause greater CO concentration because of its greater flame-cooling effect and, consequently, more incomplete combustion. This was a randomized, prospective observational study. After an initial pilot study, CO concentration was monitored during 10 trials for each of ice and water. A partially ventilated 200-L cardboard box model was developed and then used inside a chamber at -6 degrees C. Ice temperature and volume, water temperature and volume, pan size, and flame characteristics were all standardized. Temperature of the heated medium was monitored to determine time to boiling point. Carbon monoxide concentration was monitored every 30 seconds for the first 3 minutes, then every minute until the end of each 10-minute trial. There was no significant difference (P > .05) in CO production levels between ice and water. Each achieved a similar mean plateau level of approximately 400 ppm CO concentration with a similar rate of rise. However, significantly higher (P = .014) CO concentration occurred at 4 and 5 minutes when the flame underwent a yellow flare; this occurred only on 3 occasions when ice was the medium. There were no significant differences for CO production between bringing a pan of ice or water to boiling point. In a small number of ice trials, the presence of a yellow flame resulted in high CO concentration. Yellow flares might occur more often with ice or snow melting, but this has not been proven.

Subcooled forced convection boiling of trichlorotrifluoroethane

NASA Technical Reports Server (NTRS)

Dougall, R. S.; Panian, D. J.

1972-01-01

Experimental heat-transfer data were obtained for the forced-convection boiling of trichlorotrifluoroethane (R-113 or Freon-113) in a vertical annular test annular test section. The 97 data points obtained covered heat transfer by forced convection, local boiling, and fully-developed boiling. Correlating methods were obtained which accurately predicted the heat flux as a function of wall superheat (boiling curve) over the range of parameters studied.

Development of septum-free injector for gas chromatography and its application to the samples with a high boiling point.

PubMed

Ito, Hiroshi; Hayakawa, Kazuichi; Yamamoto, Atsushi; Murase, Atsushi; Hayakawa, Kazumi; Kuno, Minoru; Inoue, Yoshinori

2006-11-03

A novel apparatus with a simple structure has been developed for introducing samples into the vaporizing chamber of a gas chromatograph. It requires no septum due to the gas sealing structure over the carrier gas supply line. The septum-free injector made it possible to use injection port temperatures as high as 450 degrees C. Repetitive injection of samples with boiling points below 300 degrees C resulted in peak areas with relative standard deviations between 1.25 and 3.28% (n=5) and good linearity (r(2)>0.9942) for the calibration curve. In the analysis of polycyclic aromatic hydrocarbons and a base oil, the peak areas of components with high boiling points increased as the injection port temperature was increased to 450 degrees C.

Transetherification method

DOEpatents

Hearn, D.

1985-04-09

Transetherification is carried out in a catalytic distillation reactor, wherein the catalytic structure also serves as a distillation structure, by feeding a first ether to the catalyst bed to at least partially dissociate it into a first olefin and a first alcohol while concurrently therewith feeding either a second olefin (preferably a tertiary olefin) having a higher boiling point than said first olefin or a second alcohol having a higher boiling point than said first alcohol to the catalyst whereby either the second olefin and the first alcohol or the first olefin and the second alcohol react to form a second ether which has a higher boiling point than the first ether, which second ether is concurrently removed as a bottoms in the concurrent reaction-distillation to force that reaction to completion, while the unreacted first olefin or first alcohol is removed in the overhead. 1 fig.

Transetherification method

DOEpatents

Hearn, Dennis

1985-01-01

Transetherification is carried out in a catalytic distillation reactor, wherein the catalytic structure also serves as a distillation structure, by feeding a first ether to the catalyst bed to at least partially dissociate it into a first olefin and a first alcohol while concurrently therewith feeding either a second olefin (preferably a tertiary olefin) having a higher boiling point than said first olefin or a second alcohol having a higher boiling point than said first alcohol to the catalyst whereby either the second olefin and the first alcohol or the first olefin and the second alcohol react to form a second ether which has a higher boiling point than the first ether, which second ether is concurrently removed as a bottoms in the concurrent reaction-distillation to force that reaction to completion, while the unreacted first olefin or first alcohol is removed in the overhead.

Optimizing operating parameters of a honeycomb zeolite rotor concentrator for processing TFT-LCD volatile organic compounds with competitive adsorption characteristics.

PubMed

Lin, Yu-Chih; Chang, Feng-Tang

2009-05-30

In this study, we attempted to enhance the removal efficiency of a honeycomb zeolite rotor concentrator (HZRC), operated at optimal parameters, for processing TFT-LCD volatile organic compounds (VOCs) with competitive adsorption characteristics. The results indicated that when the HZRC processed a VOCs stream of mixed compounds, compounds with a high boiling point take precedence in the adsorption process. In addition, existing compounds with a low boiling point adsorbed onto the HZRC were also displaced by the high-boiling-point compounds. In order to achieve optimal operating parameters for high VOCs removal efficiency, results suggested controlling the inlet velocity to <1.5m/s, reducing the concentration ratio to 8 times, increasing the desorption temperature to 200-225 degrees C, and setting the rotation speed to 6.5rpm.

Coal Liquefaction desulfurization process

DOEpatents

Givens, Edwin N.

1983-01-01

In a solvent refined coal liquefaction process, more effective desulfurization of the high boiling point components is effected by first stripping the solvent-coal reacted slurry of lower boiling point components, particularly including hydrogen sulfide and low molecular weight sulfur compounds, and then reacting the slurry with a solid sulfur getter material, such as iron. The sulfur getter compound, with reacted sulfur included, is then removed with other solids in the slurry.

Further Analysis of Boiling Points of Small Molecules, CH[subscript w]F[subscript x]Cl[subscript y]Br[subscript z

ERIC Educational Resources Information Center

Beauchamp, Guy

2005-01-01

A study to present specific hypothesis that satisfactorily explain the boiling point of a number of molecules, CH[subscript w]F[subscript x]Cl[subscript y]Br[subscript z] having similar structure, and then analyze the model with the help of multiple linear regression (MLR), a data analysis tool. The MLR analysis was useful in selecting the…

Improved Estimates of Thermodynamic Parameters

NASA Technical Reports Server (NTRS)

Lawson, D. D.

1982-01-01

Techniques refined for estimating heat of vaporization and other parameters from molecular structure. Using parabolic equation with three adjustable parameters, heat of vaporization can be used to estimate boiling point, and vice versa. Boiling points and vapor pressures for some nonpolar liquids were estimated by improved method and compared with previously reported values. Technique for estimating thermodynamic parameters should make it easier for engineers to choose among candidate heat-exchange fluids for thermochemical cycles.

Prediction on dielectric strength and boiling point of gaseous molecules for replacement of SF6.

PubMed

Yu, Xiaojuan; Hou, Hua; Wang, Baoshan

2017-04-15

Developing the environment-friendly insulation gases to replace sulfur hexafluoride (SF 6 ) has attracted considerable experimental and theoretical attentions but without success. A computational methodology was presented herein for prediction on dielectric strength and boiling point of arbitrary gaseous molecules in the purpose of molecular design and screening. New structure-activity relationship (SAR) models have been established by combining the density-dependent properties of the electrostatic potential surface, including surface area and the statistical variance of the surface potentials, with the molecular properties including polarizability, electronegativity, and hardness. All the descriptors in the SAR models were calculated using density functional theory. The substitution effect of SF 6 by various functional groups was studied systematically. It was found that CF 3 is the most effective functional group to improve the dielectric strength due to the large surface area and polarizability. However, all the substitutes exhibit higher boiling points than SF 6 because the molecular hardness decreases. The balance between E r and T b could be achieved by minimizing the local polarity of the molecules. SF 5 CN and SF 5 CFO were found to be the potent candidates to replace SF 6 in view of their large dielectric strengths and low boiling points. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Design of ultrasonically-activatable nanoparticles using low boiling point perfluorocarbons.

PubMed

Sheeran, Paul S; Luois, Samantha H; Mullin, Lee B; Matsunaga, Terry O; Dayton, Paul A

2012-04-01

Recently, an interest has developed in designing biomaterials for medical ultrasonics that can provide the acoustic activity of microbubbles, but with improved stability in vivo and a smaller size distribution for extravascular interrogation. One proposed alternative is the phase-change contrast agent. Phase-change contrast agents (PCCAs) consist of perfluorocarbons (PFCs) that are initially in liquid form, but can then be vaporized with acoustic energy. Crucial parameters for PCCAs include their sensitivity to acoustic energy, their size distribution, and their stability, and this manuscript provides insight into the custom design of PCCAs for balancing these parameters. Specifically, the relationship between size, thermal stability and sensitivity to ultrasound as a function of PFC boiling point and ambient temperature is illustrated. Emulsion stability and sensitivity can be 'tuned' by mixing PFCs in the gaseous state prior to condensation. Novel observations illustrate that stable droplets can be generated from PFCs with extremely low boiling points, such as octafluoropropane (b.p. -36.7 °C), which can be vaporized with acoustic parameters lower than previously observed. Results demonstrate the potential for low boiling point PFCs as a useful new class of compounds for activatable agents, which can be tailored to the desired application. Copyright © 2012 Elsevier Ltd. All rights reserved.

Cryogenic Multichannel Pressure Sensor With Electronic Scanning

NASA Technical Reports Server (NTRS)

Hopson, Purnell, Jr.; Chapman, John J.; Kruse, Nancy M. H.

1994-01-01

Array of pressure sensors operates reliably and repeatably over wide temperature range, extending from normal boiling point of water down to boiling point of nitrogen. Sensors accurate and repeat to within 0.1 percent. Operate for 12 months without need for recalibration. Array scanned electronically, sensor readings multiplexed and sent to desktop computer for processing and storage. Used to measure distributions of pressure in research on boundary layers at high Reynolds numbers, achieved by low temperatures.

Highly Selective Membranes For The Separation Of Organic Vapors Using Super-Glassy Polymers

DOEpatents

Pinnau, Ingo; Lokhandwala, Kaaeid; Nguyen, Phuong; Segelke, Scott

1997-11-18

A process for separating hydrocarbon gases of low boiling point, particularly methane, ethane and ethylene, from nitrogen. The process is performed using a membrane made from a super-glassy material. The gases to be separated are mixed with a condensable gas, such as a C.sub.3+ hydrocarbon. In the presence of the condensable gas, improved selectivity for the low-boiling-point hydrocarbon gas over nitrogen is achieved.

Boiling points of halogenated aliphatic compounds: a quantitative structure-property relationship for prediction and validation.

PubMed

Oberg, Tomas

2004-01-01

Halogenated aliphatic compounds have many technical uses, but substances within this group are also ubiquitous environmental pollutants that can affect the ozone layer and contribute to global warming. The establishment of quantitative structure-property relationships is of interest not only to fill in gaps in the available database but also to validate experimental data already acquired. The three-dimensional structures of 240 compounds were modeled with molecular mechanics prior to the generation of empirical descriptors. Two bilinear projection methods, principal component analysis (PCA) and partial-least-squares regression (PLSR), were used to identify outliers. PLSR was subsequently used to build a multivariate calibration model by extracting the latent variables that describe most of the covariation between the molecular structure and the boiling point. Boiling points were also estimated with an extension of the group contribution method of Stein and Brown.

Oceanographic effects of the 1992 Point Loma sewage pipe spill

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casey, R.; Ciccateri, A.; Dougherty, K.

Early in early 1992, 180 million gallons of advanced primarily treated sewage emptied into 10 meters of water from the broken Point Loma sewage pipe, San Diego. For about two months a sewage boil about the size of a football field existed at the surface and within the Point Loma kelp bed. Sampling and observations taken during the spill indicated the surface waters at the spill site were grayish and smelling of sewage. The sewage water had mixed with the marine waters reducing salinity to about one-half normal (or 15 ppt.). The sediment load of the sewage coated the bladesmore » of the giant kelp and the kelp was limp and withdrawn from the surface. At the site of the main boil the kelp appeared to have dropped to the bottom. Sediments on the bottom in the boil area were mainly coarse sands as compared to the surrounding sandy-muds. Preliminary results using laboratory analysis suggest: one month into the spill no infauna were observed in the sediments or planktons in the water of the boil area, but were in the surrounding sediments and water; the observed phytoplankton were dominated by dinoflagellates and suggested red tide conditions surrounding the boil. The site has been monitored monthly since the spill to observe further impact and recovery.« less

Net vapor generation point in boiling flow of trichlorotrifluoroethane at high pressures

NASA Technical Reports Server (NTRS)

Dougall, R. S.; Lippert, T. E.

1973-01-01

The conditions at which the void in subcooled boiling starts to undergo a rapid increase were studied experimentally. The experiments were performed in a 12.7 x 9.5 mm rectangular channel. Heating was from a 3.2 mm wide strip embedded in one wall. The pressure ranged from 9.45 to 20.7 bar, mass velocity from 600 to 7000 kg/sq m sec, and subcooling from 16 to 67 C. Photographs were used to determine when detached bubbles first appeared in the bulk flow. Measurements of bubble layer thickness along the wall were also made. Results showed that the point of net vapor generation is close to the occurrence of fully-developed boiling.

Peak capacity, peak-capacity production rate, and boiling point resolution for temperature-programmed GC with very high programming rates

PubMed

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).

Application of the QSPR approach to the boiling points of azeotropes.

PubMed

Katritzky, Alan R; Stoyanova-Slavova, Iva B; Tämm, Kaido; Tamm, Tarmo; Karelson, Mati

2011-04-21

CODESSA Pro derivative descriptors were calculated for a data set of 426 azeotropic mixtures by the centroid approximation and the weighted-contribution-factor approximation. The two approximations produced almost identical four-descriptor QSPR models relating the structural characteristic of the individual components of azeotropes to the azeotropic boiling points. These models were supported by internal and external validations. The descriptors contributing to the QSPR models are directly related to the three components of the enthalpy (heat) of vaporization.

Mad Kids: How To Help Your Child Manage Anger.

ERIC Educational Resources Information Center

Beekman, Susan; Holmes, Jeanne

2002-01-01

Children move through the same anger cycle as adults and need similar coping strategies and problem solving skills. This paper presents pre-anger approaches, discussing what to do before the "boil-over" occurs, when the boiling point is reached, and after the boil-over. A sidebar presents a list of questions and activities parents can use with…

A PROCESS FOR SEPARATING AZEOTROPIC MIXTURES BY EXTRACTIVE AND CONVECTIVE DISTILLATION

DOEpatents

Frazer, J.W.

1961-12-19

A method is described for separating an azeotrope of carbon tetrachloride and 1,1,2,2-tetrafluorodinitroethane boiling at 60 deg C. The ndethod comnprises, specifically, feeding azeotrope vapors admixed with a non- reactive gas into an extractive distillation column heated to a temperature preferably somewhat above the boiling point of the constant boiling mixture. A solvent, di-n-butylphthalate, is metered into the column above the gas inlet and permitted to flow downward, earrying with it the higher bomling fraction, while the constituent having the lower boiling point passes out of the top of the column with the non-reactive gas and is collected in a nitrogen cold trap. Other solvents which alter the vapor pressure relationship may be substituted. The method is generally applicable to azeotropic mixtures. A number of specific mixtures whicb may be separated are disclosed. (AEC)

Selective production of chemicals from biomass pyrolysis over metal chlorides supported on zeolite.

PubMed

Leng, Shuai; Wang, Xinde; Cai, Qiuxia; Ma, Fengyun; Liu, Yue'e; Wang, Jianguo

2013-12-01

Direct biomass conversion into chemicals remains a great challenge because of the complexity of the compounds; hence, this process has attracted less attention than conversion into fuel. In this study, we propose a simple one-step method for converting bagasse into furfural (FF) and acetic acid (AC). In this method, bagasse pyrolysis over ZnCl2/HZSM-5 achieved a high FF and AC yield (58.10%) and a 1.01 FF/AC ratio, but a very low yield of medium-boiling point components. However, bagasse pyrolysis using HZSM-5 alone or ZnCl2 alone still remained large amounts of medium-boiling point components or high-boiling point components. The synergistic effect of HZSM-5 and ZnCl2, which combines pyrolysis, zeolite cracking, and Lewis acid-selective catalysis results in highly efficient bagasse conversion into FF and AC. Therefore, our study provides a novel, simple method for directly converting biomass into high-yield useful chemical. Copyright © 2013 Elsevier Ltd. All rights reserved.

Does pan diameter influence carbon monoxide levels during heating of water to boiling point with a camping stove?

PubMed

Leigh-Smith, Simon; Stevenson, Richard; Watt, Martin; Watt, Ian; McFadyen, Angus; Grant, Stan

2004-01-01

To determine whether pan diameter influences carbon monoxide (CO) concentration during heating of water to boiling point with a camping stove. The hypothesis was that increasing pan diameter increases CO concentration because of greater flame dispersal and a larger flame. This was a randomized, prospective study. A Coleman Dual Fuel 533 stove was used to heat pans of water to boiling point, with CO concentration monitored every 30 seconds for 5 minutes. The stove was inside a partially ventilated 200-L cardboard box model that was inside an environmental chamber at -6 degrees C. Water temperature, water volume, and flame characteristics were all standardized. Ten trials were performed for each of 2 pan diameters (base diameters of 165 mm [small] and 220 mm [large]). There was a significant difference (P = .002) between the pans for CO levels at each measurement interval from 60 seconds onward. These differences were markedly larger after 90 seconds, with a mean difference of 185 ppm (95% CI 115, 276 ppm) for all the results from 120 seconds onwards. This study has shown that there is significantly higher CO production with a large-diameter pan compared with a small-diameter pan. These findings were evident by using a camping stove to heat water to boiling point when a maximum blue flame was present throughout. Thus, in enclosed environments it is recommended that small-diameter pans be used in an attempt to prevent high CO levels.

Environmental Containment Property Estimation Using OSARs in an Expert System

DTIC Science & Technology

1990-09-14

point , melting point , aqueous solubility, octanol/water partition coefficient, vapor pressure, soil/water sorption coefficients, Henry’s Law constants...name, boiling point , melting point , or molecular weight, and the ability to transfer to any of the PEP modules. The chemical property database screen is...Yalkowski et al., 1980): log Ssupercooled liquid = log Ssolid = 0.01(MP - 25) (13) where MP is the compound’s melting point in *C. Property/protiny

The Molecular Structure of Penicillin

ERIC Educational Resources Information Center

Bentley, Ronald

2004-01-01

Overviews of the observations that constitute a structure proof for penicillin, specifically aimed at the general student population, are presented. Melting points and boiling points were criteria of purity and a crucial tool was microanalysis leading to empirical formulas.

Etherification process

DOEpatents

Smith, Jr., Lawrence A.; Hearn, Dennis; Jones, Jr., Edward M.

1990-01-01

A liquid phase process for oligomerization of C.sub.4 and C.sub.5 isoolefins or the etherification thereof with C.sub.1 to C.sub.6 alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120.degree. to 300.degree. F. wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

Oligomerization process

DOEpatents

Smith, Jr., Lawrence A.; hearn, Dennis; Jones, Jr., Edward M.

1991-01-01

A liquid phase process for oligomerization of C.sub.4 and C.sub.5 isoolefins or the etherification thereof with C.sub.1 to C.sub.6 alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300.degree. F. wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

Thermodynamics of gas and steam-blast eruptions

USGS Publications Warehouse

Mastin, L.G.

1995-01-01

Eruptions of gas or steam and non-juvenile debris are common in volcanic and hydrothermal areas. From reports of non-juvenile eruptions or eruptive sequences world-wide, at least three types (or end-members) can be identified: (1) those involving rock and liquid water initially at boiling-point temperatures ('boiling-point eruptions'); (2) those powered by gas (primarily water vapor) at initial temperatures approaching magmatic ('gas eruptions'); and (3) those caused by rapid mixing of hot rock and ground- or surface water ('mixing eruptions'). For these eruption types, the mechanical energy released, final temperatures, liquid water contents and maximum theoretical velocities are compared by assuming that the erupting mixtures of rock and fluid thermally equilibrate, then decompress isentropically from initial, near-surface pressure (???10 MPa) to atmospheric pressure. Maximum mechanical energy release is by far greatest for gas eruptions (??????1.3 MJ/kg of fluid-rock mixture)-about one-half that of an equivalent mass of gunpowder and one-fourth that of TNT. It is somewhat less for mixing eruptions (??????0.4 MJ/kg), and least for boiling-point eruptions (??????0.25 MJ/kg). The final water contents of crupted boiling-point mixtures are usually high, producing wet, sloppy deposits. Final erupted mixtures from gas eruptions are nearly always dry, whereas those from mixing eruptions vary from wet to dry. If all the enthalpy released in the eruptions were converted to kinetic energy, the final velocity (vmax) of these mixtures could range up to 670 m/s for boiling-point eruptions and 1820 m/s for gas eruptions (highest for high initial pressure and mass fractions of rock (mr) near zero). For mixing eruptions, vmax ranges up to 1150 m/s. All observed eruption velocities are less than 400 m/s, largely because (1) most solid material is expelled when mr is high, hence vmax is low; (2) observations are made of large blocks the velocities of which may be less than the average for the mixture; (3) heat from solid particles is not efficiently transferred to the fluid during the eruptions; and (4) maximum velocities are reduced by choked flow or friction in the conduit. ?? 1995 Springer-Verlag.

The effect of several crude oils and some petroleum distillation fractions on intestinal absorption in ducklings (Anas platyhynchos).

PubMed

Crocker, A D; Cronshaw, J; Holmes, W N

1975-01-01

Ducklings given hypertonic saline drinking water show significant increases in the rates of Na+ and water transfer across the intestinal mucosa. These increased rates of transfer are maintained as long as the birds are fed dypertonic saline. Oral administration of a single small dose of crude oil had no effect on the basal rate of mucosal transfer in freshwater-maintained ducklings but the adaptive response of the mucosa is suppressed in birds given hypertonic saline. When crude oils from eight different geographical locations were tested, the degree of inhibition varied between them; the greatest and smallest degrees of inhibition being observed following administration of Kuwait and North Slope, Alaska, crude oils respectively. The effects of distallation fractions derived from two chemically different crude oils were also examined. The volume of each distallation fraction administered corresponded to its relative abundance in the crude oil from which it was derived. The inhibitory effect was not associated exclusively with the same distallation fractions from each oil. A highly naphthenic crude oil from the San Joaquin Valley, California, showed the greatest inhibitory activity in the least abundant (2%), low boiling point (smaller than 245 degrees C) fraction and the least inhibitory activity in the highest boiling point (greater than 482 degrees C) most abundant (47%) fraction. In contrast, a highly paraffinic crude oil from Paradox Basin, Utah, showed the greatest inhibitory effect with the highest boiling point fraction and a minimal effect with the lowest boiling point fraction; the relative abundances of these two fractions in the crude oil represented 27 and 28% respectively. Water-soluble extracts of both crude oils also had inhibitory effects on mucosal transfer rates and these roughly proportionate to the inhibitory potency of the low boiling point fraction of each oil. Weathered samples of San Joaquin Valley, California, and the Paradox Basin, Utah, oils showed greater effects than corresponding samples of unweathered oils even though most of the low molecular weight material from both oils was either evaporated or solubilized in the underlying water during the 36-h weathering period.

Comparison of vapor formation of water at the solid/water interface to colloidal solutions using optically excited gold nanostructures.

PubMed

Baral, Susil; Green, Andrew J; Livshits, Maksim Y; Govorov, Alexander O; Richardson, Hugh H

2014-02-25

The phase transformation properties of liquid water to vapor is characterized by optical excitation of the lithographically fabricated single gold nanowrenches and contrasted to the phase transformation properties of gold nanoparticles located and optically excited in a bulk solution system [two and three dimensions]. The 532 nm continuous wave excitation of a single gold nanowrench results in superheating of the water to the spinodal decomposition temperature of 580 ± 20 K with bubble formation below the spinodal decomposition temperature being a rare event. Between the spinodal decomposition temperature and the boiling point liquid water is trapped into a metastable state because a barrier to vapor nucleation exists that must be overcome before the thermodynamically stable state is realized. The phase transformation for an optically heated single gold nanowrench is different from the phase transformation of optically excited colloidal gold nanoparticles solution where collective heating effects dominates and leads to the boiling of the solution exactly at the boiling point. In the solution case, the optically excited ensemble of nanoparticles collectively raises the ambient temperature of water to the boiling point where liquid is converted into vapor. The striking difference in the boiling properties of the single gold nanowrench and the nanoparticle solution system can be explained in terms of the vapor-nucleation mechanism, the volume of the overheated liquid, and the collective heating effect. The interpretation of the observed regimes of heating and vaporization is consistent with our theoretical modeling. In particular, we explain with our theory why the boiling with the collective heating in a solution requires 3 orders of magnitude less intensity compared to the case of optically driven single nanowrench.

Atom-type-based AI topological descriptors: application in structure-boiling point correlations of oxo organic compounds.

PubMed

Ren, Biye

2003-01-01

Structure-boiling point relationships are studied for a series of oxo organic compounds by means of multiple linear regression (MLR) analysis. Excellent MLR models based on the recently introduced Xu index and the atom-type-based AI indices are obtained for the two subsets containing respectively 77 ethers and 107 carbonyl compounds and a combined set of 184 oxo compounds. The best models are tested using the leave-one-out cross-validation and an external test set, respectively. The MLR model produces a correlation coefficient of r = 0.9977 and a standard error of s = 3.99 degrees C for the training set of 184 compounds, and r(cv) = 0.9974 and s(cv) = 4.16 degrees C for the cross-validation set, and r(pred) = 0.9949 and s(pred) = 4.38 degrees C for the prediction set of 21 compounds. For the two subsets containing respectively 77 ethers and 107 carbonyl compounds, the quality of the models is further improved. The standard errors are reduced to 3.30 and 3.02 degrees C, respectively. Furthermore, the results obtained from this study indicate that the boiling points of the studied oxo compound dominantly depend on molecular size and also depend on individual atom types, especially oxygen heteroatoms in molecules due to strong polar interactions between molecules. These excellent structure-boiling point models not only provide profound insights into the role of structural features in a molecule but also illustrate the usefulness of these indices in QSPR/QSAR modeling of complex compounds.

Exfoliating and Dispersing Few-Layered Graphene in Low-Boiling-Point Organic Solvents towards Solution-Processed Optoelectronic Device Applications.

PubMed

Zhang, Lu; Miao, Zhongshuo; Hao, Zhen; Liu, Jun

2016-05-06

With normal organic surfactants, graphene can only be dispersed in water and cannot be dispersed in low-boiling-point organic solvents, which hampers its application in solution-processed organic optoelectronic devices. Herein, we report the exfoliation of graphite into graphene in low-boiling-point organic solvents, for example, methanol and acetone, by using edge-carboxylated graphene quantum dots (ECGQD) as the surfactant. The great capability of ECGQD for graphene dispersion is due to its ultralarge π-conjugated unit that allows tight adhesion on the graphene surface through strong π-π interactions, its edge-carboxylated structure that diminishes the steric effects of the oxygen-containing functional groups on the basal plane of ECGQD, and its abundance of carboxylic acid groups for solubility. The graphene dispersion in methanol enables the application of graphene:ECGQD as a cathode interlayer in polymer solar cells (PSCs). Moreover, the PSC device performance of graphene:ECGQD is better than that of Ca, the state-of-the-art cathode interlayer material. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Generalized syntheses of nanocrystal-graphene hybrids in high-boiling-point organic solvents.

PubMed

Pang, Danny Wei-Ping; Yuan, Fang-Wei; Chang, Yan-Cheng; Li, Guo-An; Tuan, Hsing-Yu

2012-08-07

Nanocrystal-graphene have been proposed as a new kind of promising hybrid for a wide range of application areas including catalysts, electronics, sensors, biomedicine, and energy storage, etc. Although a variety of methods have been developed for the preparation of hybrids, a facile and general synthetic approach is still highly required. In this study, nanocrystal-graphene hybrids were successfully synthesized in high-boiling-point organic solvents. Graphene oxide (GO) nanosheets were modified by oleylamine (OLA) to form a OLA-GO complex in order to be readily incorporated into hydrophobic synthesis. A rich library of highly crystalline nanocrystals, with types including noble metal, metal oxide, magnetic material and semiconductor were successfully grown on chemically converted graphene (CCG), which is simultaneously reduced from GO during the synthesis. High boiling-point solvents afford sufficient thermal energy to assure the high-quality crystalline nature of NCs, therefore the post-annealing process is obviated. Controlled experiments revealed that OLA-GO triggers heterogeneous nucleation and serves as excellent nuclei anchorage media. The protocol developed here brings one step closer to achieve "unity in diversity" on the preparation of nanocrystal-graphene hybrids.

Measurement of total acid number (TAN) and TAN boiling point distribution in petroleum products by electrospray ionization mass spectrometry.

PubMed

Qian, Kuangnan; Edwards, Kathleen E; Dechert, Gary J; Jaffe, Stephen B; Green, Larry A; Olmstead, William N

2008-02-01

We report a new method for rapid measurement of total acid number (TAN) and TAN boiling point (BP) distribution for petroleum crude and products. The technology is based on negative ion electrospray ionization mass spectrometry (ESI-MS) for selective ionization of petroleum acid and quantification of acid structures and molecular weight distributions. A chip-based nanoelectrospray system enables microscale (<200 mg) and higher throughput (20 samples/h) measurement. Naphthenic acid structures were assigned based on nominal masses of a set of predefined acid structures. Stearic acid is used as an internal standard to calibrate ESI-MS response factors for quantification purposes. With the use of structure-property correlations, boiling point distributions of TAN values can be calculated from the composition. The rapid measurement of TAN BP distributions by ESI is demonstrated for a series of high-TAN crudes and distillation cuts. TAN values determined by the technique agree well with those by the titration method. The distributed properties compare favorably with those measured by distillation and measurement of TAN of corresponding cuts.

Investigation of sources, properties and preparation of distillate test fuels

NASA Technical Reports Server (NTRS)

Bowden, J. N.; Erwin, J.

1983-01-01

Distillate test fuel blends were generated for prescribed variations in composition and physical properties. Fuels covering a wide range in properties and composition which would provide a matrix of fuels for possible use in future combustion research programs were identified. Except for tetralin the blending components were all from typical refinery streams. Property variation blends span a boiling range within 150 C to 335 C, freezing point -23 C to -43 C, aromatic content 20 to 50 volume percent, hydrogen content 11.8 to 14.2 mass percent, viscosity 4 and 11 cSt (-20 C), and naphthalenes 8 and 16 volume percent. Composition variation blends were made with two base stocks, one paraffinic and the other napthenic. To each base stock was added each of three aromatic type fuels (alkyl benzenes, tetralin, and naphthalenes) for assigned initial boiling point, final boiling point, and hydrogen content. The hydrogen content was 13.5 mass percent for the paraffinic base stock blends and 12.5 mass percent and 11.5 mass percent for the naphthenic base stock blends. Sample 5-gallon quantities of all blends were prepared and analyzed.

Microwave-Assisted Superheating and/or Microwave-Specific Superboiling (Nucleation-Limited Boiling) of Liquids Occurs under Certain Conditions but is Mitigated by Stirring.

PubMed

Ferrari, Anthony; Hunt, Jacob; Stiegman, Albert; Dudley, Gregory B

2015-12-04

Temporary superheating and sustained nucleation-limited "superboiling" of unstirred liquids above the normal atmospheric boiling point have been documented during microwave heating. These phenomena are reliably observed under prescribed conditions, although the duration (of superheating) and magnitude (of superheating and superboiling) vary according to system parameters such as volume of the liquid and the size and shape of the vessel. Both phenomena are mitigated by rapid stirring with an appropriate stir bar and/or with the addition of boiling chips, which provide nucleation sites to support the phase-change from liquid to gas. With proper experimental design and especially proper stirring, the measured temperature of typical organic reaction mixtures heated at reflux will be close to the normal boiling point temperature of the solvent, whether heated using microwave radiation or conventional convective heat transfer. These observations are important to take into consideration when comparing reaction rates under conventional and microwave heating.

Initial fuel temperature effects on burning rate of pool fire.

PubMed

Chen, Bing; Lu, Shou-Xiang; Li, Chang-Hai; Kang, Quan-Sheng; Lecoustre, Vivien

2011-04-15

The influence of the initial fuel temperature on the burning behavior of n-heptane pool fire was experimentally studied at the State Key Laboratory of Fire Science (SKLFS) large test hall. Circular pool fires with diameters of 100mm, 141 mm, and 200 mm were considered with initial fuel temperatures ranging from 290 K to 363 K. Burning rate and temperature distributions in fuel and vessel wall were recorded during the combustion. The burning rate exhibited five typical stages: initial development, steady burning, transition, bulk boiling burning, and decay. The burning rate during the steady burning stage was observed to be relatively independent of the initial fuel temperature. In contrast, the burning rate of the bulk boiling burning stage increases with increased initial fuel temperature. It was also observed that increased initial fuel temperature decreases the duration of steady burning stage. When the initial temperature approaches the boiling point, the steady burning stage nearly disappears and the burning rate moves directly from the initial development stage to the transition stage. The fuel surface temperature increases to its boiling point at the steady burning stage, shortly after ignition, and the bulk liquid reaches boiling temperature at the bulk boiling burning stage. No distinguished cold zone is formed in the fuel bed. However, boiling zone is observed and the thickness increases to its maximum value when the bulk boiling phenomena occurs. Copyright © 2011 Elsevier B.V. All rights reserved.

Leidenfrost Point and Estimate of the Vapour Layer Thickness

ERIC Educational Resources Information Center

Gianino, Concetto

2008-01-01

In this article I describe an experiment involving the Leidenfrost phenomenon, which is the long lifetime of a water drop when it is deposited on a metal that is much hotter than the boiling point of water. The experiment was carried out with high-school students. The Leidenfrost point is measured and the heat laws are used to estimate the…

Etherification process

DOEpatents

Smith, L.A. Jr.; Hearn, D.; Jones, E.M. Jr.

1990-08-21

A liquid phase process is described for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled. 2 figs.

Reactor for exothermic reactions

DOEpatents

Smith, Jr., Lawrence A.; Hearn, Dennis; Jones, Jr., Edward M.

1993-01-01

A liquid phase process for oligomerization of C.sub.4 and C.sub.5 isoolefins or the etherification thereof with C.sub.1 to C.sub.6 alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120.degree. to 300.degree. F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

Method for conducting exothermic reactions

DOEpatents

Smith, L. Jr.; Hearn, D.; Jones, E.M. Jr.

1993-01-05

A liquid phase process for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F. wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

Method for conducting exothermic reactions

DOEpatents

Smith, Jr., Lawrence; Hearn, Dennis; Jones, Jr., Edward M.

1993-01-01

A liquid phase process for oligomerization of C.sub.4 and C.sub.5 isoolefins or the etherification thereof with C.sub.1 to C.sub.6 alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120.degree. to 300.degree. F. wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

Reactor for exothermic reactions

DOEpatents

Smith, L.A. Jr.; Hearn, D.; Jones, E.M. Jr.

1993-03-02

A liquid phase process is described for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

Oligomerization process

DOEpatents

Smith, L.A. Jr.; Hearn, D.; Jones, E.M. Jr.

1991-03-26

A liquid phase process is described for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled. 2 figures.

Boiling point determination using adiabatic Gibbs ensemble Monte Carlo simulations: Application to metals described by embedded-atom potentials

NASA Astrophysics Data System (ADS)

Gelb, Lev D.; Chakraborty, Somendra Nath

2011-12-01

The normal boiling points are obtained for a series of metals as described by the "quantum-corrected Sutton Chen" (qSC) potentials [S.-N. Luo, T. J. Ahrens, T. Çağın, A. Strachan, W. A. Goddard III, and D. C. Swift, Phys. Rev. B 68, 134206 (2003)]. Instead of conventional Monte Carlo simulations in an isothermal or expanded ensemble, simulations were done in the constant-NPH adabatic variant of the Gibbs ensemble technique as proposed by Kristóf and Liszi [Chem. Phys. Lett. 261, 620 (1996)]. This simulation technique is shown to be a precise tool for direct calculation of boiling temperatures in high-boiling fluids, with results that are almost completely insensitive to system size or other arbitrary parameters as long as the potential truncation is handled correctly. Results obtained were validated using conventional NVT-Gibbs ensemble Monte Carlo simulations. The qSC predictions for boiling temperatures are found to be reasonably accurate, but substantially underestimate the enthalpies of vaporization in all cases. This appears to be largely due to the systematic overestimation of dimer binding energies by this family of potentials, which leads to an unsatisfactory description of the vapor phase.

High Energy Density Cryogenic Capacitors

DTIC Science & Technology

2006-07-07

S Sublimation point - 10 -78 .50C at 1 atm gas (D Critical point CL Triple point 0.1 -5 6.6C at 5.11 atm 0.01 CO2 gas 0.001 -140 -120 -100 -80 -60...dramatically increase the dielectric breakdown stress in a polymer film is by reducing its temperature to 77K, the boiling point of liquid nitrogen at 1 bar...minimum, and maximum breakdown strengths measured in units of Volts per micron; and the final column is the number of data points taken on that

Morphological control in polymer solar cells using low-boiling-point solvent additives

NASA Astrophysics Data System (ADS)

Mahadevapuram, Rakesh C.

In the global search for clean, renewable energy sources, organic photovoltaics (OPVs) have recently been given much attention. Popular modern-day OPVs are made from solution-processible, carbon-based polymers (e.g. the model poly(3-hexylthiophene) that are intimately blended with fullerene derivatives (e.g. [6,6]-phenyl-C71-butyric acid methyl ester) to form what is known as the dispersed bulk-heterojunction (BHJ). This BHJ architecture has produced some of the most efficient OPVs to date, with reports closing in on 10% power conversion efficiency. To push efficiencies further into double digits, many groups have identified the BHJ nanomorphology---that is, the phase separations and grain sizes within the polymer: fullerene composite---as a key aspect in need of control and improvement. As a result, many methods, including thermal annealing, slow-drying (solvent) annealing, vapor annealing, and solvent additives, have been developed and studied to promote BHJ self-organization. Processing organic photovoltaic (OPV) blend solutions with high-boiling-point solvent additives has recently been used for morphological control in BHJ OPV cells. Here we show that even low-boiling-point solvents can be effective additives. When P3HT:PCBM OPV cells were processed with a low-boiling-point solvent tetrahydrafuran as an additive in parent solvent o-dichlorobenzene, charge extraction increased leading to fill factors as high as 69.5%, without low work-function cathodes, electrode buffer layers or thermal treatment. This was attributed to PCBM demixing from P3HT domains and better vertical phase separation, as indicated by photoluminescence lifetimes, hole mobilities, and shunt leakage currents. Dependence on solvent parameters and applicability beyond P3HT system was also investigated.

Effect of hydroprocessing severity on characteristics of jet fuel from OSCO 2 and Paraho distillates

NASA Technical Reports Server (NTRS)

Prok, G. M.; Flores, F. J.; Seng, G. T.

1981-01-01

Jet A boiling range fuels and broad-property research fuels were produced by hydroprocessing shale oil distillates, and their properties were measured to characterize the fuels. The distillates were the fraction of whole shale oil boiling below 343 C from TOSCO 2 and Paraho syncrudes. The TOSCO 2 was hydroprocessed at medium severity, and the Paraho was hydroprocessed at high, medium, and low severities. Fuels meeting Jet A requirements except for the freezing point were produced from the medium severity TOSCO 2 and the high severity Paraho. Target properties of a broad property research fuel were met by the medium severity TOSCO 2 and the high severity Paraho except for the freezing point and a high hydrogen content. Medium and low severity Paraho jet fuels did not meet thermal stability and freezing point requirements.

Radioactive-gas separation technique

NASA Technical Reports Server (NTRS)

Haney, R.; King, K. J.; Nellis, D. O.; Nisson, R. S.; Robling, P.; Womack, W.

1977-01-01

Cryogenic technique recovers gases inexpensively. Method uses differences in vapor pressures, melting points, and boiling points of components in gaseous mixture. Series of temperature and pressure variations converts gases independently to solid and liquid states, thereby simplifying separation. Apparatus uses readily available cryogen and does not require expensive refrigeration equipment.

Numerical model study of radio frequency vessel sealing thermodynamics

NASA Astrophysics Data System (ADS)

Pearce, John

2015-03-01

Several clinically successful clinical radio frequency vessel-sealing devices are currently available. The dominant thermodynamic principles at work involve tissue water vaporization processes. It is necessary to thermally denature vessel collagen, elastin and their adherent proteins to achieve a successful fusion. Collagens denature at middle temperatures, between about 60 and 90 C depending on heating time and rate. Elastin, and its adherent proteins, are more thermally robust, and require temperatures in excess of the boiling point of water at atmospheric pressure to thermally fuse. Rapid boiling at low apposition pressures leads to steam vacuole formation, brittle tissue remnants and frequently to substantial disruption in the vessel wall, particularly in high elastin-content arteries. High apposition pressures substantially increase the equilibrium boiling point of tissue water and are necessary to ensure a high probability of a successful seal. The FDM numerical models illustrate the beneficial effects of high apposition pressures.

Research of the cold shield in cryogenic liquid storage

NASA Astrophysics Data System (ADS)

Chen, L. B.; Zheng, J. P.; Wu, X. L.; Cui, C.; Zhou, Y.; Wang, J. J.

2017-12-01

To realize zero boil-off storage of cryogenic liquids, a cryocooler that can achieve a temperature below the boiling point temperature of the cryogenic liquid is generally needed. Taking into account that the efficiency of the cryocooler will be higher at a higher operating temperature, a novel thermal insulation system using a sandwich container filled with cryogenic liquid with a higher boiling point as a cold radiation shield between the cryogenic tank and the vacuum shield in room temperature is proposed to reduce the electricity power consumption. A two-stage cryocooler or two separate cryocoolers are adopted to condense the evaporated gas from the cold shield and the cryogenic tank. The calculation result of a 55 liter liquid hydrogen tank with a liquid nitrogen shield shows that only 14.4 W of electrical power is needed to make all the evaporated gas condensation while 121.7 W will be needed without the liquid nitrogen shield.

[Prediction of the side-cut product yield of atmospheric/vacuum distillation unit by NIR crude oil rapid assay].

PubMed

Wang, Yan-Bin; Hu, Yu-Zhong; Li, Wen-Le; Zhang, Wei-Song; Zhou, Feng; Luo, Zhi

2014-10-01

In the present paper, based on the fast evaluation technique of near infrared, a method to predict the yield of atmos- pheric and vacuum line was developed, combined with H/CAMS software. Firstly, the near-infrared (NIR) spectroscopy method for rapidly determining the true boiling point of crude oil was developed. With commercially available crude oil spectroscopy da- tabase and experiments test from Guangxi Petrochemical Company, calibration model was established and a topological method was used as the calibration. The model can be employed to predict the true boiling point of crude oil. Secondly, the true boiling point based on NIR rapid assay was converted to the side-cut product yield of atmospheric/vacuum distillation unit by H/CAMS software. The predicted yield and the actual yield of distillation product for naphtha, diesel, wax and residual oil were compared in a 7-month period. The result showed that the NIR rapid crude assay can predict the side-cut product yield accurately. The near infrared analytic method for predicting yield has the advantages of fast analysis, reliable results, and being easy to online operate, and it can provide elementary data for refinery planning optimization and crude oil blending.

Energy conversion system involving change in the density of an upwardly moving liquid

DOEpatents

Petrick, Michael

1989-01-01

A system for converting thermal energy into electrical energy includes a fluid reservoir, a relatively high boiling point fluid such as lead or a lead alloy within the reservoir, a downcomer defining a vertical fluid flow path communicating at its upper end with the reservoir and an upcomer defining a further vertical fluid flow path communicating at its upper end with the reservoir. A variable area nozzle of rectangular section may terminate the upper end of the upcomer and the lower end of the of the downcomer communicates with the lower end of the upcomer. A mixing chamber is located at the lower end portion of the upcomer and receives a second relatively low boiling point fluid such as air, the mixing chamber serving to introduce the low boiling point fluid into the upcomer so as to produce bubbles causing the resultant two-phase fluid to move at high velocity up the upcomer. Means are provided for introducing heat into the system preferably between the lower end of the downcomer and the lower end of the upcomer. Power generating means are associated with the one of the vertical fluid flow paths one such power generating means being a magneto hydrodynamic electrical generator.

Concerning a new classification of tricyanides

NASA Technical Reports Server (NTRS)

Krafft, F.; Vonhansen, A.

1979-01-01

A new classification series of tricyanides is presented. Several tricyanides are synthesized by a simple method from aluminum chloride, benzonitrile, and a respective alkyl or phenyl chloride, purified by recrystallization and distillation, and then analyzed. Structural formulae are suggested, and molecular weights, melting points, and boiling points are determined for each.

40 CFR 1065.710 - Gasoline.

Code of Federal Regulations, 2010 CFR

2010-07-01

...: Initial boiling point °C 24-35 2 24-36 10% point °C 49-57 37-48 ASTM D86-07a. 50% point °C 93-110 82-101... m3/m3 Maximum, 0.10 Maximum, 0.175 ASTM D1319-03. Aromatics Maximum, 0.35 Maximum, 0.304 Saturates.../liter Maximum, 0.0013 Maximum, 0.005 ASTM D3231-07. Total sulfur mg/kg Maximum, 80 Maximum, 80 ASTM...

40 CFR 1065.703 - Distillate diesel fuel.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 1 Cetane Number 40-50 40-50 40-50 ASTM D613-05. Distillation range: Initial boiling point °C 171-204 171-204 171-204 ASTM D86-07a. 10 pct. point 204-238 204-238 204-238 50 pct. point 243-282 243-282 243...-37 ASTM D4052-96e01. Total sulfur, ultra low sulfur mg/kg 7-15 See 40 CFR 80.580. Total sulfur, low...

Boiling point determination using adiabatic Gibbs ensemble Monte Carlo simulations: application to metals described by embedded-atom potentials.

PubMed

Gelb, Lev D; Chakraborty, Somendra Nath

2011-12-14

The normal boiling points are obtained for a series of metals as described by the "quantum-corrected Sutton Chen" (qSC) potentials [S.-N. Luo, T. J. Ahrens, T. Çağın, A. Strachan, W. A. Goddard III, and D. C. Swift, Phys. Rev. B 68, 134206 (2003)]. Instead of conventional Monte Carlo simulations in an isothermal or expanded ensemble, simulations were done in the constant-NPH adabatic variant of the Gibbs ensemble technique as proposed by Kristóf and Liszi [Chem. Phys. Lett. 261, 620 (1996)]. This simulation technique is shown to be a precise tool for direct calculation of boiling temperatures in high-boiling fluids, with results that are almost completely insensitive to system size or other arbitrary parameters as long as the potential truncation is handled correctly. Results obtained were validated using conventional NVT-Gibbs ensemble Monte Carlo simulations. The qSC predictions for boiling temperatures are found to be reasonably accurate, but substantially underestimate the enthalpies of vaporization in all cases. This appears to be largely due to the systematic overestimation of dimer binding energies by this family of potentials, which leads to an unsatisfactory description of the vapor phase. © 2011 American Institute of Physics

Rapid Evaporation of microbubbles

NASA Astrophysics Data System (ADS)

Gautam, Jitendra; Esmaeeli, Asghar

2008-11-01

When a liquid is heated to a temperature far above its boiling point, it evaporates abruptly. Boiling of liquid at high temperatures can be explosive and destructive, and poses a potential hazard for a host of industrial processes. Explosive boiling may occur if a cold and volatile liquid is brought into contact with a hot and non-volatile liquid, or if a liquid is superheated or depressurized rapidly. Such possibilities are realized, for example, in the depressurization of low boiling point liquefied natural gas (LNG) in the pipelines or storage tanks as a result of a leak. While boiling of highly heated liquids can be destructive at macroscale, the (nearly) instantaneous pace of the process and the release of large amount of kinetic energy make the phenomena extremely attractive at microscale where it is possible to utilize the released energy to derive micromechanical systems. For instance, there is currently a growing interest in micro-explosion of liquid for generation of micro bubbles for actuation purposes. The aim of the current study is to gain a fundamental understanding of the subject using direct numerical simulations. In particular, we seek to investigate the boundary between stable and unstable nucleus growth in terms of the degree of liquid superheat and to compare the dynamics of unstable and stable growth.

Facilitating Students' Conceptual Understanding of Boiling Using a Four-Step Constructivist Teaching Method

ERIC Educational Resources Information Center

Calik, Muammer

2008-01-01

The aim of the work presented here was to devise an activity associated with factors affecting boiling points. The intervention used a four-step constructivist-based teaching strategy, which was subsequently evaluated by a cohort of students. Data collection consisted of application of a purpose designed questionnaire consisting of four open-ended…

Students' Understanding of Boiling Points and Intermolecular Forces

ERIC Educational Resources Information Center

Schmidt, Hans-Jurgen; Kaufmann, Birgit; Treagust, David F.

2009-01-01

In introductory chemistry courses students are presented with the model that matter is composed of particles, and that weak forces of attraction exist between them. This model is used to interpret phenomena such as solubility and melting points, and aids in understanding the changes in states of matter as opposed to chemical reactions. We…

Prospective Chemistry Teachers' Misconceptions about Colligative Properties: Boiling Point Elevation and Freezing Point Depression

ERIC Educational Resources Information Center

Pinarbasi, Tacettin; Sozbilir, Mustafa; Canpolat, Nurtac

2009-01-01

This study aimed at identifying prospective chemistry teachers' misconceptions of colligative properties. In order to fulfill this aim, a diagnostic test composed of four open-ended questions was used. The test was administered to seventy-eight prospective chemistry teachers just before qualifying to teaching in secondary schools. Nine different…

Study of thermal behavior of vitamin D3 by pyrolysis-GC-MS in combination with boiling point-retention time correlation.

PubMed

Sun, Yu'an; Liu, Baoxia; Wang, Guoqing; Zhang, Rongjie; Xie, Bing

2005-01-01

The thermal behavior of vitamin D3 was studied based on pyrolysis-GC-MS technique. It was pyrolyzed at 600 degrees C, 750 degrees C, 900 degrees C, respectively. The pyrolysis product were separated With an HP-5 column and identified by the NIST mass spectral search program in combination with the correlation of boiling point and retention time (BP-RT). There are totally 50 components, including mono aromatics and polycyclic aromatic hydrocarbons (PAHs), were determined. It is shown that the contents of the PAHs are increasing with the increasing of the pyrolysis temperature. The contents of the determined components vary from 0.04% to 37.08%.

Thermoplastic fusion bonding using a pressure-assisted boiling point control system.

PubMed

Park, Taehyun; Song, In-Hyouk; Park, Daniel S; You, Byoung Hee; Murphy, Michael C

2012-08-21

A novel thermoplastic fusion bonding method using a pressure-assisted boiling point (PABP) control system was developed to apply precise temperatures and pressures during bonding. Hot embossed polymethyl methacrylate (PMMA) components containing microchannels were sealed using the PABP system. Very low aspect ratio structures (AR = 1/100, 10 μm in depth and 1000 μm in width) were successfully sealed without collapse or deformation. The integrity and strength of the bonds on the sealed PMMA devices were evaluated using leakage and rupture tests; no leaks were detected and failure during the rupture tests occurred at pressures greater than 496 kPa. The PABP system was used to seal 3D shaped flexible PMMA devices successfully.

Liquid Oxygen Propellant Densification Unit Ground Tested With a Large-Scale Flight-Weight Tank for the X-33 Reusable Launch Vehicle

NASA Technical Reports Server (NTRS)

Tomsik, Thomas M.

2002-01-01

Propellant densification has been identified as a critical technology in the development of single-stage-to-orbit reusable launch vehicles. Technology to create supercooled high-density liquid oxygen (LO2) and liquid hydrogen (LH2) is a key means to lowering launch vehicle costs. The densification of cryogenic propellants through subcooling allows 8 to 10 percent more propellant mass to be stored in a given unit volume, thereby improving the launch vehicle's overall performance. This allows for higher propellant mass fractions than would be possible with conventional normal boiling point cryogenic propellants, considering the normal boiling point of LO2 and LH2.

Improving efficiency and color purity of poly(9,9-dioctylfluorene) through addition of a high boiling-point solvent of 1-chloronaphthalene.

PubMed

Liang, Junfei; Yu, Lei; Sen Zhao; Ying, Lei; Liu, Feng; Yang, Wei; Peng, Junbiao; Cao, Yong

2016-07-15

In this work, the β-phase of poly(9,9-dioctylfluorene) (PFO) was used as a probe to study the effects of the addition of a high boiling-point solvent of 1-chloronaphthalene on the nanostructures and electroluminescence of PFO films. Both absorption and photoluminescence spectra showed that the content of the β-phase in PFO film was obviously enhanced as a result of the addition of a small amount of 1-chloronaphthalene into the processing solvent of p-xylenes. Apparently rougher morphology associated with the effectively enhanced ordering of polymer chains across the entire film was observed for films processed from p-xylene solutions consisting of a certain amount of 1-chloronaphthalene, as revealed by atomic force microscopy and grazing incidence x-ray diffraction measurements. In addition to the effects on the nanostructures of films, of particular interest is that the performance and color purity of polymer light-emitting devices can be noticeably enhanced upon the addition of 1-chloronaphthalene. These observations highlight the importance of controlling the nanostructures of the emissive layer, and demonstrate that the addition of a low volume ratio of high boiling-point additive can be a promising strategy to attain high-performance polymer light-emitting diodes.

Notes on Vapor Pressure Equilibria Measurements

NASA Astrophysics Data System (ADS)

Krieger, Albert G.; Henderson, John W.

1996-11-01

After reading the article in this Journal (1), we would like to share our experience with a similar experiment based on an earlier article in this Journal (2). Freshman students at our institution use manometers and 24/40 ground-glass distillation apparatus (abandoned by our organic chemistry classes) to measure boiling points at reduced pressures. Distilled water and 2-methyl-1-propanol are typical liquids of interest. Students enter their collected data into an Excel template which generates graphs of P vs. T and log P vs 1/T to demonstrate the nonlinear and linear relationships that exist between vapor pressures and temperatures. The templates use the Clausius-Clapeyron equation to determine the normal boiling point and the enthalpy of vaporization of the liquid studies. The boiling point determined for water is 100 oC and for 2-methyl-1-propanol is 106 oC, within 2 o of the CRC Handbook data. We have found that the availability of state-of-the-art equipment need not limit the ability to teach and demonstrate fundamental principles. The Excel template (Macintosh) is available upon request domestically and for the cost of international postage for others. Literature Cited 1. Kidahl, N.; Berka, L. H. J. Chem. Educ. 1995, 72, 258. 2. Schaber, P. M. J. Chem. Educ. 1985, 62, 345.

Distribution of volatile organic compounds (VOCs) in surface water, soil, and groundwater within a chemical industry park in Eastern China.

PubMed

Liu, Benhua; Chen, Liang; Huang, Linxian; Wang, Yongseng; Li, Yuehua

2015-01-01

This paper focuses on the distribution of volatile organic compounds (VOCs) in the surface water, soil, and groundwater within a chemical industry park in Eastern China. At least one VOC was detected in each of the 20 sampling sites, and the maximum number of VOCs detected in the surface water, groundwater, and soil were 13, 16, and 14, respectively. Two of the 10 VOCs with elevated concentrations detected in surface water, groundwater, and soil were chloroform and 1,2-dichloroethane. The characteristics of VOCs, which include volatility, boiling point, and solubility, could significantly affect their distribution in surface water, soil, and groundwater. However, due to the direct discharging of chemical industry wastewater into surface water, higher concentrations of VOCs (except chloroform) were detected in surface water than in soil and groundwater. Fortunately, the higher volatility of VOCs prevents the VOCs from impacting groundwater, which helps to maintain a lower concentration of VOCs in the groundwater than in both surface water and soil. This is because pollutants with relatively higher boiling points and lower solubilities have higher detection frequencies in soil, and contaminants with relatively lower boiling points and higher solubilities have higher detection frequencies in water, notably in surface water.

A numerical investigation of the effect of surface wettability on the boiling curve.

PubMed

Hsu, Hua-Yi; Lin, Ming-Chieh; Popovic, Bridget; Lin, Chii-Ruey; Patankar, Neelesh A

2017-01-01

Surface wettability is recognized as playing an important role in pool boiling and the corresponding heat transfer curve. In this work, a systematic study of pool boiling heat transfer on smooth surfaces of varying wettability (contact angle range of 5° - 180°) has been conducted and reported. Based on numerical simulations, boiling curves are calculated and boiling dynamics in each regime are studied using a volume-of-fluid method with contact angle model. The calculated trends in critical heat flux and Leidenfrost point as functions of surface wettability are obtained and compared with prior experimental and theoretical predictions, giving good agreement. For the first time, the effect of contact angle on the complete boiling curve is shown. It is demonstrated that the simulation methodology can be used for studying pool boiling and related dynamics and providing more physical insights.

A numerical investigation of the effect of surface wettability on the boiling curve

PubMed Central

Lin, Ming-Chieh; Popovic, Bridget; Lin, Chii-Ruey; Patankar, Neelesh A.

2017-01-01

Surface wettability is recognized as playing an important role in pool boiling and the corresponding heat transfer curve. In this work, a systematic study of pool boiling heat transfer on smooth surfaces of varying wettability (contact angle range of 5° − 180°) has been conducted and reported. Based on numerical simulations, boiling curves are calculated and boiling dynamics in each regime are studied using a volume-of-fluid method with contact angle model. The calculated trends in critical heat flux and Leidenfrost point as functions of surface wettability are obtained and compared with prior experimental and theoretical predictions, giving good agreement. For the first time, the effect of contact angle on the complete boiling curve is shown. It is demonstrated that the simulation methodology can be used for studying pool boiling and related dynamics and providing more physical insights. PMID:29125847

Numerical Simulation of Pulsation Flow in the Vapour Channel of Short Low Temperature Heat Pipes at High Heat Loads

NASA Astrophysics Data System (ADS)

Seryakov, A. V.; Konkin, A. V.

2017-11-01

The results of the numerical simulation of pulsations in the Laval-liked vapour channel of short low-temperature range heat pipes (HPs) are presented. The numerical results confirmed the experimentally obtained increase of the frequency of pulsations in the vapour channel of short HPs with increasing overheat of the porous evaporator relative to the boiling point of the working fluid. The occurrence of pressure pulsations inside the vapour channel in a short HPs is a complex phenomenon associated with the boiling beginning in the capillary-porous evaporator at high heat loads, and appearance the excess amount of vapour above it, leading to the increase in pressure P to a value at which the boiling point TB of the working fluid becomes higher than the evaporator temperature Tev. Vapour clot spreads through the vapour channel and condense, and then a rarefaction wave return from condenser in the evaporator, the boiling in which is resumed and the next cycle of the pulsations is repeated. Numerical simulation was performed using finite element method implemented in the commercial program ANSYS Multiphisics 14.5 in the two-dimensional setting of axis symmetric moist vapour flow with third kind boundary conditions.

A new procedure for the determination of distillation temperature distribution of high-boiling petroleum products and fractions.

PubMed

Boczkaj, Grzegorz; Przyjazny, Andrzej; Kamiński, Marian

2011-03-01

The distribution of distillation temperatures of liquid and semi-fluid products, including petroleum fractions and products, is an important process and practical parameter. It provides information on properties of crude oil and content of particular fractions, classified on the basis of their boiling points, as well as the optimum conditions of atmospheric or vacuum distillation. At present, the distribution of distillation temperatures is often investigated by simulated distillation (SIMDIS) using capillary gas chromatography (CGC) with a short capillary column with polydimethylsiloxane as the stationary phase. This paper presents the results of investigations on the possibility of replacing currently used CGC columns for SIMDIS with a deactivated fused silica capillary tube without any stationary phase. The SIMDIS technique making use of such an empty fused silica column allows a considerable lowering of elution temperature of the analytes, which results in a decrease of the final oven temperature while ensuring a complete separation of the mixture. This eliminates the possibility of decomposition of less thermally stable mixture components and bleeding of the stationary phase which would result in an increase of the detector signal. It also improves the stability of the baseline, which is especially important in the determination of the end point of elution, which is the basis for finding the final temperature of distillation. This is the key parameter for the safety process of hydrocracking, where an excessively high final temperature of distillation of a batch can result in serious damage to an expensive catalyst bed. This paper compares the distribution of distillation temperatures of the fraction from vacuum distillation of petroleum obtained using SIMDIS with that obtained by the proposed procedure. A good agreement between the two procedures was observed. In addition, typical values of elution temperatures of n-paraffin standards obtained by the two procedures were compared. Finally, the agreement between boiling points of polar compounds determined from their retention times and actual boiling points was investigated.

Design of an Improved Heater Array to Measure Microscale Wall Heat Transfer

NASA Technical Reports Server (NTRS)

Kim, Jungho; Chng, Choon Ping; Kalkur, T. S.

1996-01-01

An improved array of microscale heaters is being developed to measure the heat transfer coefficient at many points underneath individual bubbles during boiling as a function of space and time. This heater array enables the local heat transfer from a surface during the bubble growth and departure process to be measured with very high temporal and spatial resolution, and should allow better understanding of the boiling heat transfer mechanisms by pin-pointing when and where in the bubble departure cycle large amounts of wall heat transfer occur. Such information can provide much needed data regarding the important heat transfer mechanisms during the bubble departure cycle, and can serve as benchmarks to validate many of the analytical and numerical models used to simulate boiling. The improvements to the heater array include using a silicon-on-quartz substrate to reduce thermal cross-talk between the heaters, decreased space between the heaters, increased pad sizes on the heaters, and progressive heater sizes. Some results using the present heater array are discussed.

Gas chromatographic simulated distillation-mass spectrometry for the determination of the boiling point distributions of crude oils

PubMed

Roussis; Fitzgerald

2000-04-01

The coupling of gas chromatographic simulated distillation with mass spectrometry for the determination of the distillation profiles of crude oils is reported. The method provides the boiling point distributions of both weight and volume percent amounts. The weight percent distribution is obtained from the measured total ion current signal. The total ion current signal is converted to weight percent amount by calibration with a reference crude oil of a known distillation profile. Knowledge of the chemical composition of the crude oil across the boiling range permits the determination of the volume percent distribution. The long-term repeatability is equivalent to or better than the short-term repeatability of the currently available American Society for Testing and Materials (ASTM) gas chromatographic method for simulated distillation. Results obtained by the mass spectrometric method are in very good agreement with results obtained by conventional methods of physical distillation. The compositional information supplied by the method can be used to extensively characterize crude oils.

Numerical modeling of thermal conductive heating in fractured bedrock.

PubMed

Baston, Daniel P; Falta, Ronald W; Kueper, Bernard H

2010-01-01

Numerical modeling was employed to study the performance of thermal conductive heating (TCH) in fractured shale under a variety of hydrogeological conditions. Model results show that groundwater flow in fractures does not significantly affect the minimum treatment zone temperature, except near the beginning of heating or when groundwater influx is high. However, fracture and rock matrix properties can significantly influence the time necessary to remove all liquid water (i.e., reach superheated steam conditions) in the treatment area. Low matrix permeability, high matrix porosity, and wide fracture spacing can contribute to boiling point elevation in the rock matrix. Consequently, knowledge of these properties is important for the estimation of treatment times. Because of the variability in boiling point throughout a fractured rock treatment zone and the absence of a well-defined constant temperature boiling plateau in the rock matrix, it may be difficult to monitor the progress of thermal treatment using temperature measurements alone. Copyright © 2010 The Author(s). Journal compilation © 2010 National Ground Water Association.

Jet aircraft hydrocarbon fuels technology

NASA Technical Reports Server (NTRS)

Longwell, J. P. (Editor)

1978-01-01

A broad specification, referee fuel was proposed for research and development. This fuel has a lower, closely specified hydrogen content and higher final boiling point and freezing point than ASTM Jet A. The workshop recommended various priority items for fuel research and development. Key items include prediction of tradeoffs among fuel refining, distribution, and aircraft operating costs; combustor liner temperature and emissions studies; and practical simulator investigations of the effect of high freezing point and low thermal stability fuels on aircraft fuel systems.

Enrichment of light hydrocarbon mixture

DOEpatents

Yang, Dali [Los Alamos, NM; Devlin, David [Santa Fe, NM; Barbero, Robert S [Santa Cruz, NM; Carrera, Martin E [Naperville, IL; Colling, Craig W [Warrenville, IL

2011-11-29

Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

Enrichment of light hydrocarbon mixture

DOEpatents

Yang,; Dali, [Los Alamos, NM; Devlin, David [Santa Fe, NM; Barbero, Robert S [Santa Cruz, NM; Carrera, Martin E [Naperville, IL; Colling, Craig W [Warrenville, IL

2010-08-10

Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

Subatmospheric vapor pressures evaluated from internal-energy measurements

NASA Astrophysics Data System (ADS)

Duarte-Garza, H. A.; Magee, J. W.

1997-01-01

Vapor pressures were evaluated from measured internal-energy changes in the vapor+liquid two-phase region, Δ U (2). The method employed a thermodynamic relationship between the derivative quantity (ϖ U (2)/ϖ V) T and the vapor pressure ( p σ) and its temperature derivative (ϖ p/ϖ T)σ. This method was applied at temperatures between the triple point and the normal boiling point of three substances: 1,1,1,2-tetrafluoroethane (R134a), pentafluoroethane (R125), and difluoromethane (R32). Agreement with experimentally measured vapor pressures near the normal boiling point (101.325 kPa) was within the experimental uncertainty of approximately ±0.04 kPa (±0.04%). The method was applied to R134a to test the thermodynamic consistency of a published p-p-T equation of state with an equation for p σ for this substance. It was also applied to evaluate published p σ data which are in disagreement by more than their claimed uncertainty.

The purity of water at hospital and at home as a problem of intercultural understanding.

PubMed

Burghart, R

1996-03-01

Women in a provincial town in southern Nepal were instructed by medical doctors and compounders to boil water, and to keep it boiling for 15 minutes before mixing it with infant formula or oral rehydration salts. Most women ignored the advice. Those who seemed to follow it merely brought the water to boil. This report describes how and why women boil water and assesses the health implications of their practices. The failure of women to adopt "proper" procedures procedures provides a point of entry into an analysis of the role of intercultural dialogue in exposing one's presuppositions about health and empowering one to change them.

46 CFR Appendix B to Subpart C to... - Substance Technical Guidelines, Benzene

Code of Federal Regulations, 2010 CFR

2010-10-01

... Subpart C to Part 197—Substance Technical Guidelines, Benzene I. Physical and Chemical Data (a) Substance...: 71-43-2). (b) Physical data. (1) Boiling point (760 mm Hg): 80.1 °C (176 °F). (2) Specific gravity..., and Reactivity Hazard Data (a) Fire. (1) Flash point (closed cup): −11 °C (12 °F). (2) Autoignition...

Correlation of physical properties with molecular structure for some dicyclic hydrocarbons having high thermal-energy release per unit volume

NASA Technical Reports Server (NTRS)

Wise, P H; Serijan, K T; Goodman, I A

1951-01-01

As part of a program to study the correlation between molecular structure and physical properties of high-density hydrocarbons, the net heats of combustion, melting points, boiling points, densities, and kinematic viscosities of some hydrocarbons in the 2-n-alkylbiphenyl, 1,1-diphenylalkane, diphenylalkane, 1,1-dicyclohexylalkane, and dicyclohexylalkane series are presented.

Rediscovering the Kernels of Truth in the Urban Legends of the Freshman Composition Classroom

ERIC Educational Resources Information Center

Lovoy, Thomas

2004-01-01

English teachers, as well as teachers within other disciplines, often boil down abstract principles to easily explainable bullet points. Students often pick up and retain these points but fail to grasp the broader contexts that make them relevant. It is therefore sometimes helpful to revisit some of the more common of these "rules of thumb" to…

About the International System of Units (SI) Part II. Organization and General Principles

ERIC Educational Resources Information Center

Aubrecht, Gordon J., II; French, Anthony P.; Iona, Mario

2011-01-01

As all physicists know, all units are arbitrary. The numbering system is anthropocentric; for example, the Celsius scale of temperature has 100 degrees between the boiling point of water at STP and the freezing point of water. The number 100 is chosen because human beings have 10 fingers. The best units might be based on physical constants, for…

Microbiological effectiveness of disinfecting water by boiling in rural Guatemala.

PubMed

Rosa, Ghislaine; Miller, Laura; Clasen, Thomas

2010-03-01

Boiling is the most common means of treating water in the home and the benchmark against which alternative point-of-use water treatment options must be compared. In a 5-week study in rural Guatemala among 45 households who claimed they always or almost always boiled their drinking water, boiling was associated with a 86.2% reduction in geometric mean thermotolerant coliforms (TTC) (N = 206, P < 0.0001). Despite consistent levels of fecal contamination in source water, 71.2% of stored water samples from self-reported boilers met the World Health Organization guidelines for safe drinking water (0 TTC/100 mL), and 10.7% fell within the commonly accepted low-risk category of (1-10 TTC/100 mL). As actually practiced in the study community, boiling significantly improved the microbiological quality of drinking water, though boiled and stored drinking water is not always free of fecal contaminations.

Evaluation of correlations of flow boiling heat transfer of R22 in horizontal channels.

PubMed

Zhou, Zhanru; Fang, Xiande; Li, Dingkun

2013-01-01

The calculation of two-phase flow boiling heat transfer of R22 in channels is required in a variety of applications, such as chemical process cooling systems, refrigeration, and air conditioning. A number of correlations for flow boiling heat transfer in channels have been proposed. This work evaluates the existing correlations for flow boiling heat transfer coefficient with 1669 experimental data points of flow boiling heat transfer of R22 collected from 18 published papers. The top two correlations for R22 are those of Liu and Winterton (1991) and Fang (2013), with the mean absolute deviation of 32.7% and 32.8%, respectively. More studies should be carried out to develop better ones. Effects of channel dimension and vapor quality on heat transfer are analyzed, and the results provide valuable information for further research in the correlation of two-phase flow boiling heat transfer of R22 in channels.

Evaluation of Correlations of Flow Boiling Heat Transfer of R22 in Horizontal Channels

PubMed Central

Fang, Xiande; Li, Dingkun

2013-01-01

The calculation of two-phase flow boiling heat transfer of R22 in channels is required in a variety of applications, such as chemical process cooling systems, refrigeration, and air conditioning. A number of correlations for flow boiling heat transfer in channels have been proposed. This work evaluates the existing correlations for flow boiling heat transfer coefficient with 1669 experimental data points of flow boiling heat transfer of R22 collected from 18 published papers. The top two correlations for R22 are those of Liu and Winterton (1991) and Fang (2013), with the mean absolute deviation of 32.7% and 32.8%, respectively. More studies should be carried out to develop better ones. Effects of channel dimension and vapor quality on heat transfer are analyzed, and the results provide valuable information for further research in the correlation of two-phase flow boiling heat transfer of R22 in channels. PMID:23956695

Microbiological Effectiveness of Disinfecting Water by Boiling in Rural Guatemala

PubMed Central

Rosa, Ghislaine; Miller, Laura; Clasen, Thomas

2010-01-01

Boiling is the most common means of treating water in the home and the benchmark against which alternative point-of-use water treatment options must be compared. In a 5-week study in rural Guatemala among 45 households who claimed they always or almost always boiled their drinking water, boiling was associated with a 86.2% reduction in geometric mean thermotolerant coliforms (TTC) (N = 206, P < 0.0001). Despite consistent levels of fecal contamination in source water, 71.2% of stored water samples from self-reported boilers met the World Health Organization guidelines for safe drinking water (0 TTC/100 mL), and 10.7% fell within the commonly accepted low-risk category of (1–10 TTC/100 mL). As actually practiced in the study community, boiling significantly improved the microbiological quality of drinking water, though boiled and stored drinking water is not always free of fecal contaminations. PMID:20207876

An Industrial Project

ERIC Educational Resources Information Center

Daniels, D. J.; And Others

1975-01-01

Describes the commercial uses, industrial production and laboratory production of 2-methylpentane-2,4-diol. Suggests extensions for the experiment in the areas of boiling point/composition curves and alkaline depolymerization. (GS)

SUBCOOLING DETECTOR

DOEpatents

McCann, J.A.

1963-12-17

A system for detecting and measuring directly the subcooling margin in a liquid bulk coolant is described. A thermocouple sensor is electrically heated, and a small amount of nearly stagnant bulk coolant is heated to the boiling point by this heated thermocouple. The sequential measurement of the original ambient temperature, zeroing out this ambient temperature, and then measuring the boiling temperature of the coolant permits direct determination of the subcooling margin of the ambient liquid. (AEC)

Science at Home: Measuring a Thermophysical Property of Water with a Microwave Oven

ERIC Educational Resources Information Center

Levine, Zachary H.

2018-01-01

An attempt to calibrate a conventional oven led to making a measurement of a thermophysical property of water using items found in the author's home. Specifically, the ratio of the energy required to heat water from the melting point to boiling to the energy required to completely boil away the water is found to be 5.7. This may be compared to the…

Confinement by carbon nanotubes drastically alters the boiling and critical behavior of water droplets.

PubMed

Chaban, Vitaly V; Prezhdo, Victor V; Prezhdo, Oleg V

2012-03-27

Vapor pressure grows rapidly above the boiling temperature, and past the critical point liquid droplets disintegrate. Our atomistic simulations show that this sequence of events is reversed inside carbon nanotubes (CNT). Droplets disintegrate first and at low temperature, while pressure remains low. The droplet disintegration temperature is independent of the CNT diameter. In contrast, depending on CNT diameter, a temperature that is much higher than the bulk boiling temperature is required to raise the internal pressure. The control over pressure by CNT size can be useful for therapeutic drug delivery. © 2012 American Chemical Society

Effects of ionic liquids on the performance of IPMC

NASA Astrophysics Data System (ADS)

Kim, Min Jung; Park, Sang Woo; Won, Joohye; Nah, Changwoon

2017-04-01

One of the issues in operating the IPMC actuators in air condition is the limited lifetime due to the evaporation of aqueous electrolytes like water. Several attempts were already made for solving the problem using an ionic liquid (IL) with higher boiling point. In this study, three different ILs having similar boiling point but different molecular weight were employed in the IPMC actuators. The actuation performance, notably speed and lifetime, were measured and they are compared with that of water-based IPMC actuator. The lower molecular weight IL showed a comparable actuation speed of water due to faster movement of the ion cluster. The lifetime of the water-based IPMC actuator was found to be only 3 hr. However, the IL-based IPMC actuators showed much improved service life.

Relationship between potency and boiling point of general anesthetics: a thermodynamic consideration.

PubMed

Dastmalchi, S; Barzegar-Jalali, M

2000-07-20

The most important group of nonspecific drugs is that of the general anesthetics. These nonspecific compounds vary greatly in structure, from noble gases such as Ar or Xe to complex steroids. Since the development of clinical anesthesia over a century ago, there has been a vast amount of research and speculation concerning the mechanism of action of general anesthetics. Despite these efforts, the exact mechanism remains unknown. Many theories of narcosis do not explain how unconsciousness is produced at a molecular level, but instead relate some physicochemical property of anesthetic agents to their anesthetic potencies. In this paper, we address some of those physicochemical properties, with more emphasis on correlating the anesthetic potency of volatile anesthetics to their boiling points based on thermodynamic principles.

Catalytic two-stage coal hydrogenation process using extinction recycle of heavy liquid fraction

DOEpatents

MacArthur, J.B.; Comolli, A.G.; McLean, J.B.

1989-10-17

A process is described for catalytic two-stage hydrogenation and liquefaction of coal with selective extinction recycle of all heavy liquid fractions boiling above a distillation cut point of about 600--750 F to produce increased yields of low-boiling hydrocarbon liquid and gas products. In the process, the particulate coal feed is slurried with a process-derived liquid solvent normally boiling above about 650 F and fed into a first stage catalytic reaction zone operated at conditions which promote controlled rate liquefaction of the coal, while simultaneously hydrogenating the hydrocarbon recycle oils. The first stage reactor is maintained at 710--800 F temperature, 1,000--4,000 psig hydrogen partial pressure, and 10-90 lb/hr per ft[sup 3] catalyst space velocity. Partially hydrogenated material withdrawn from the first stage reaction zone is passed directly to the second stage catalytic reaction zone maintained at 760--860 F temperature for further hydrogenation and hydroconversion reactions. A 600--750 F[sup +] fraction containing 0--20 W % unreacted coal and ash solids is recycled to the coal slurrying step. If desired, the cut point lower boiling fraction can be further catalytically hydrotreated. By this process, the coal feed is successively catalytically hydrogenated and hydroconverted at selected conditions, to provide significantly increased yields of desirable low-boiling hydrocarbon liquid products and minimal production of hydrocarbon gases, and no net production of undesirable heavy oils and residuum materials. 2 figs.

Catalytic two-stage coal hydrogenation process using extinction recycle of heavy liquid fraction

DOEpatents

MacArthur, James B.; Comolli, Alfred G.; McLean, Joseph B.

1989-01-01

A process for catalytic two-stage hydrogenation and liquefaction of coal with selective extinction recycle of all heavy liquid fractions boiling above a distillation cut point of about 600.degree.-750.degree. F. to produce increased yields of low-boiling hydrocarbon liquid and gas products. In the process, the particulate coal feed is slurried with a process-derived liquid solvent normally boiling above about 650.degree. F. and fed into a first stage catalytic reaction zone operated at conditions which promote controlled rate liquefaction of the coal, while simultaneously hydrogenating the hydrocarbon recycle oils. The first stage reactor is maintained at 710.degree.-800.degree. F. temperature, 1000-4000 psig hydrogen partial pressure, and 10-90 lb/hr per ft.sup.3 catalyst space velocity. Partially hydrogenated material withdrawn from the first stage reaction zone is passed directly to the second stage catalytic reaction zone maintained at 760.degree.-860.degree. F. temperature for further hydrogenation and hydroconversion reactions. A 600.degree.-750.degree. F..sup.+ fraction containing 0-20 W % unreacted coal and ash solids is recycled to the coal slurrying step. If desired, the cut point lower boiling fraction can be further catalytically hydrotreated. By this process, the coal feed is successively catalytically hydrogenated and hydroconverted at selected conditions, to provide significantly increased yields of desirable low-boiling hydrocarbon liquid products and minimal production of hydrocarbon gases, and no net production of undesirable heavy oils and residuum materials.

ELECTROLYTIC PROCESS FOR PRODUCING METALS

DOEpatents

Kopelman, B.; Holden, R.B.

1961-06-01

A method is described for reducing beryllium halides to beryllium. The beryllfum halide fs placed in an eutectic mixture of alkali halides and alkaline earth halides. The constituents of this eutectic bath are so chosen that it has a melting point less than the boiling point of mercury, which acts as a cathode for the system. The beryllium metal is then deposited in the mercury upon electrolysis.

An investigation of transition boiling mechanisms of subcooled water under forced convective conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwang-Won, Lee; Sang-Yong, Lee

1995-09-01

A mechanistic model for forced convective transition boiling has been developed to investigate transition boiling mechanisms and to predict transition boiling heat flux realistically. This model is based on a postulated multi-stage boiling process occurring during the passage time of the elongated vapor blanket specified at a critical heat flux (CHF) condition. Between the departure from nucleate boiling (DNB) and the departure from film boiling (DFB) points, the boiling heat transfer is established through three boiling stages, namely, the macrolayer evaporation and dryout governed by nucleate boiling in a thin liquid film and the unstable film boiling characterized by themore » frequent touches of the interface and the heated wall. The total heat transfer rates after the DNB is weighted by the time fractions of each stage, which are defined as the ratio of each stage duration to the vapor blanket passage time. The model predictions are compared with some available experimental transition boiling data. The parametric effects of pressure, mass flux, inlet subcooling on the transition boiling heat transfer are also investigated. From these comparisons, it can be seen that this model can identify the crucial mechanisms of forced convective transition boiling, and that the transition boiling heat fluxes including the maximum heat flux and the minimum film boiling heat flux are well predicted at low qualities/high pressures near 10 bar. In future, this model will be improved in the unstable film boiling stage and generalized for high quality and low pressure situations.« less

New Security and Justice Sector Partnership Models: Implications of the Arab Uprisings

DTIC Science & Technology

2014-01-01

clear boiling point that even before the Arab uprisings erupted, Clinton warned regional regimes that they needed to change or risk “sinking into the...but without any clear operational definition of security capac- ity, no consistent logic for allocating funds and determining appropriate expenditure...reference point for gauging performance and determining whether and how program implementation needs to be altered. While this approach is most

Developing a vacuum thermal stripping - acid absorption process for ammonia recovery from anaerobic digester effluent.

PubMed

Ukwuani, Anayo T; Tao, Wendong

2016-12-01

To prevent acetoclastic methanogens from ammonia inhibition in anaerobic digestion of protein-rich substrates, ammonia needs to be removed or recovered from digestate. This paper presents an innovative ammonia recovery process that couples vacuum thermal stripping with acid absorption. Ammonia is stripped out of digestate boiling at a temperature below the normal boiling point due to vacuum. Stripped ammonia is absorbed to a sulfuric acid solution, forming ammonium sulfate crystals as a marketable product. Three common types of digestate were found to have boiling point temperature-vacuum curves similar to water. Seven combinations of boiling temperature and vacuum (50 °C 16.6 kPa, 58 °C 20.0 kPa, 65 °C 25.1 kPa, 70 °C 33.6 kPa, 80 °C 54.0 kPa, 90 °C 74.2 kPa, and 100 °C 101.3 kPa) were tested for batch stripping of ammonia in dairy manure digestate. 93.3-99.9% of ammonia was stripped in 3 h. The Lewis-Whitman model fitted ammonia stripping process well. Ammonia mass transfer coefficient was significantly higher at boiling temperature 65-100 °C and vacuum pressure 25.1-101.3 kPa than 50-58 °C and 16.6-20.0 kPa. The low ammonia saturation concentrations (0-24 mg N/L) suggested a large driving force to strip ammonia. The optimum boiling point temperature - vacuum pressure for ammonia recovery in a recirculation line of a mesophilic digester was 65 °C and 25.1 kPa, at which the ammonia mass transfer coefficient was as high as 37.3 mm/h. Installation of a demister and liquid trap could avoid negative effects of higher stripping temperature and stronger vacuum on formation of ammonium sulfate crystals. Pilot tests demonstrated that high-purity ammonium sulfate crystals could be produced by controlling sulfuric acid content and maintaining acid solution saturated with ammonium sulfate. Although volatile organic compounds such as cyclohexene were found in the final acid solutions, no volatile organic compounds were found in the recovered crystals. Copyright © 2016 Elsevier Ltd. All rights reserved.

Alternate working fluids for solar air conditioning applications

NASA Technical Reports Server (NTRS)

Evans, R. D.; Beck, J. K.

1978-01-01

An experimental investigation of sixteen different refrigerant-absorbent fluid pairs has been carried out in order to determine their suitability as the working fluid in a solar-powered absorption cycle air conditioner. The criteria used in the initial selection of a refrigerant-absorbent pair included: high affinity (large negative deviation from Raoult's Law), high solubility, low specific heat, low viscosity, stability, corrosive properties, safety, and cost. For practical solar considerations of a fluid pair, refrigerants were selected with low boiling points whereas absorbent fluids were selected with a boiling point considerably above that of the refrigerant. Additional restrictions are determined by the operating temperatures of the absorber and the generator; these temperatures were specified as 100 F (39 C) and 170 F (77 C). Data are presented for a few selected pressures at the specified absorber and generator temperatures.

How Do Organic Chemistry Students Understand and Apply Hydrogen Bonding?

NASA Astrophysics Data System (ADS)

Henderleiter, J.; Smart, R.; Anderson, J.; Elian, O.

2001-08-01

Students completing a year-long organic chemistry sequence were interviewed to assess how they understood, explained, and applied knowledge of hydrogen bonding to the physical behavior of molecules. Students were asked to define hydrogen bonding and explain situations in which hydrogen bonding could occur. They were asked to predict and explain how hydrogen bonding influences boiling point, the solubility of molecules, and NMR and IR spectra. Results suggest that although students may be able to give appropriate definitions of hydrogen bonding and may recognize when this phenomenon can occur, significant numbers cannot apply their knowledge of hydrogen bonding to physical properties of molecules or to the interpretation of spectral data. Some possess misconceptions concerning boiling points and the ability of molecules to induce hydrogen bonding. Instructional strategies must be adjusted to address these issues.

Ink-jet printing of graphene for flexible electronics: An environmentally-friendly approach

NASA Astrophysics Data System (ADS)

Capasso, A.; Del Rio Castillo, A. E.; Sun, H.; Ansaldo, A.; Pellegrini, V.; Bonaccorso, F.

2015-12-01

Mechanical flexibility is considered an asset in consumer electronics and next-generation electronic systems. Printed and flexible electronic devices could be embedded into clothing or other surfaces at home or office or in many products such as low-cost sensors integrated in transparent and flexible surfaces. In this context inks based on graphene and related two-dimensional materials (2DMs) are gaining increasing attention owing to their exceptional (opto)electronic, electrochemical and mechanical properties. The current limitation relies on the use of solvents, providing stable dispersions of graphene and 2DMs and fitting the proper fluidic requirements for printing, which are in general not environmentally benign, and with high boiling point. Non-toxic and low boiling point solvents do not possess the required rheological properties (i.e., surface tension, viscosity and density) for the solution processing of graphene and 2DMs. Such solvents (e.g., water, alcohols) require the addition of stabilizing agents such as polymers or surfactants for the dispersion of graphene and 2DMs, which however unavoidably corrupt their properties, thus preventing their use for the target application. Here, we demonstrate a viable strategy to tune the fluidic properties of water/ethanol mixtures (low-boiling point solvents) to first effectively exfoliate graphite and then disperse graphene flakes to formulate graphene-based inks. We demonstrate that such inks can be used to print conductive stripes (sheet resistance of ~13 kΩ/□) on flexible substrates (polyethylene terephthalate), moving a step forward towards the realization of graphene-based printed electronic devices.

Plastic catalytic pyrolysis to fuels as tertiary polymer recycling method: effect of process conditions.

PubMed

Gulab, Hussain; Jan, Muhammad Rasul; Shah, Jasmin; Manos, George

2010-01-01

This paper presents results regarding the effect of various process conditions on the performance of a zeolite catalyst in pyrolysis of high density polyethylene. The results show that polymer catalytic degradation can be operated at relatively low catalyst content reducing the cost of a potential industrial process. As the polymer to catalyst mass ratio increases, the system becomes less active, but high temperatures compensate for this activity loss resulting in high conversion values at usual batch times and even higher yields of liquid products due to less overcracking. The results also show that high flow rate of carrier gas causes evaporation of liquid products falsifying results, as it was obvious from liquid yield results at different reaction times as well as the corresponding boiling point distributions. Furthermore, results are presented regarding temperature effects on liquid selectivity. Similar values resulted from different final reactor temperatures, which are attributed to the batch operation of the experimental equipment. Since polymer and catalyst both undergo the same temperature profile, which is the same up to a specific time independent of the final temperature. Obviously, this common temperature step determines the selectivity to specific products. However, selectivity to specific products is affected by the temperature, as shown in the corresponding boiling point distributions, with higher temperatures showing an increased selectivity to middle boiling point components (C(8)-C(9)) and lower temperatures increased selectivity to heavy components (C(14)-C(18)).

QSPR modeling: graph connectivity indices versus line graph connectivity indices

PubMed

Basak; Nikolic; Trinajstic; Amic; Beslo

2000-07-01

Five QSPR models of alkanes were reinvestigated. Properties considered were molecular surface-dependent properties (boiling points and gas chromatographic retention indices) and molecular volume-dependent properties (molar volumes and molar refractions). The vertex- and edge-connectivity indices were used as structural parameters. In each studied case we computed connectivity indices of alkane trees and alkane line graphs and searched for the optimum exponent. Models based on indices with an optimum exponent and on the standard value of the exponent were compared. Thus, for each property we generated six QSPR models (four for alkane trees and two for the corresponding line graphs). In all studied cases QSPR models based on connectivity indices with optimum exponents have better statistical characteristics than the models based on connectivity indices with the standard value of the exponent. The comparison between models based on vertex- and edge-connectivity indices gave in two cases (molar volumes and molar refractions) better models based on edge-connectivity indices and in three cases (boiling points for octanes and nonanes and gas chromatographic retention indices) better models based on vertex-connectivity indices. Thus, it appears that the edge-connectivity index is more appropriate to be used in the structure-molecular volume properties modeling and the vertex-connectivity index in the structure-molecular surface properties modeling. The use of line graphs did not improve the predictive power of the connectivity indices. Only in one case (boiling points of nonanes) a better model was obtained with the use of line graphs.

Crosslinking of Perfluorocarbon Polymers

DTIC Science & Technology

1977-04-01

absorption in the 8.0-8.7 M region, the presence of oxide can be excluded and thus the higher than to date reported melting point is most likely due...did not produce any epoxide. Apparently the stabilizer present in the Mallinckrodt hydrogen peroxide ( acetanilide ) promoted degradation of the epoxide...DTA curve (see Figure 3) Freon E-7 has a boiling point above 2500C. The broadness of the endotherm indicates that it is a multi-component mixture

Fundamental Studies on Aluminum Fuels

DTIC Science & Technology

1944-12-01

Isooctr.no 200 C. Additives in the Syster. Aluminum Dilaur- r.te Cyclohexp.ne 201 2. Metathesis (Double Decomposition ) of Aluminum So^pc -ith...changes of hydrolysis -ire reduced (p»47). It has a sharp melting point (p. 88) and x-r:ty diffraotion pattern (p.71 ) and upon partial...of decomposition products. (In the same «ay as by distillation an acaotrope is often produoed and has a constant boiling point). It muat be noted

The renaissance of life near the boiling point - at last, genetics and metabolic engineering.

PubMed

Adams, Michael W W; Kelly, Robert M

2017-01-01

We discuss here the prospects for biotechnology of extreme thermophilic microorganisms. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

A Sweet Springtime Adventure.

ERIC Educational Resources Information Center

Carlone, Edward J.

1989-01-01

Describes how the tapping of maple trees can be used to teach lessons in science on boiling points, density, solubility, and other sugaring projects in the curricula. Outlines activities and precautions to follow when doing this project. (RT)

Analysis of Alcohols.

ERIC Educational Resources Information Center

McCullough, Brother Thomas

1984-01-01

Presents a novel approach to identification of unknown alcohols using experimental measurements of boiling point and viscosity which are easily obtained without expensive equipment of instrumentation. Provides instructions for preparing capillary viscometer, listing special hints for obtaining good results. (JM)

Volatilization of iodine from nitric acid using peroxide

DOEpatents

Cathers, G.I.; Shipman, C.J.

1975-10-21

A method for removing radioactive iodine from nitric acid solution by adding hydrogen peroxide to the solution while concurrently holding the solution at the boiling point and distilling hydrogen iodide from the solution is reported.

Transient boiling heat transfer in saturated liquid nitrogen and F113 at standard and zero gravity

NASA Technical Reports Server (NTRS)

Oker, E.; Merte, H., Jr.

1973-01-01

Transient and steady state nucleate boiling in saturated LN2 and F113 at standard and near zero gravity conditions were investigated for the horizontal up, vertical and horizontal down orientations of the heating surface. Two distinct regimes of heat transfer mechanisms were observed during the interval from the step increase of power input to the onset of nucleate boiling: the conduction and convection dominated regimes. The time duration in each regime was considerably shorter with LN2 than with F113, and decreased as heat flux increased, as gravity was reduced, and as the orientation was changed from horizontal up to horizontal down. In transient boiling, boiling initiates at a single point following the step increase in power, and then spreads over the surface. The delay time for the inception of boiling at the first site, and the velocity of spread of boiling varies depending upon the heat flux, orientation, body force, surface roughness and liquid properties, and are a consequence of changes in boundary layer temperature levels associated with changes in natural convection. Following the step increase in power input, surface temperature overshoot and undershoot occur before the steady state boiling temperature level is established.

Development of Advanced ISS-WPA Catalysts for Organic Oxidation at Reduced Pressure/Temperature

NASA Technical Reports Server (NTRS)

Yu, Ping; Nalette, Tim; Kayatin, Matthew

2016-01-01

The Water Processor Assembly (WPA) at International Space Station (ISS) processes a waste stream via multi-filtration beds, where inorganic and non-volatile organic contaminants are removed, and a catalytic reactor, where low molecular weight organics not removed by the adsorption process are oxidized at elevated pressure in the presence of oxygen and elevated temperature above the normal water boiling point. Operation at an elevated pressure requires a more complex system design compared to a reactor that could operate at ambient pressure. However, catalysts currently available have insufficient activity to achieve complete oxidation of the organic load at a temperature less than the water boiling point and ambient pressure. Therefore, it is highly desirable to develop a more active and efficient catalyst at ambient pressure and a moderate temperature that is less than water boiling temperature. This paper describes our efforts in developing high efficiency water processing catalysts. Different catalyst support structures and coating metals were investigated in subscale reactors and results were compared against the flight WPA catalyst. Detailed improvements achieved on alternate metal catalysts at ambient pressure and 200 F will also be presented in the paper.

Process for producing low-sulfur boiler fuel by hydrotreatment of solvent deashed SRC

DOEpatents

Roberts, George W.; Tao, John C.

1985-01-01

In this invention, a process is disclosed characterized by heating a slurry of coal in the presence of a process-derived recycle solvent and passing same to a dissolver zone, separating the resultant gases and liquid/solid products therefrom, vacuum distilling the liquid/solids products, separating the portions of the liquid/solids vacuum distillation effluent into a solid ash, unconverted coal particles and SRC material having a boiling point above 850.degree. F. and subjecting same to a critical solvent deashing step to provide an ash-free SRC product. The lighter liquid products from the vacuum distillation possess a boiling point below 850.degree. F. and are passed through a distillation tower, from which recycled solvent is recovered in addition to light distillate boiling below 400.degree. F. (overhead). The ash-free SRC product in accompanyment with at least a portion of the process derived solvent is passed in combination to a hydrotreating zone containing a hydrogenation catalyst and in the presence of hydrogen is hydroprocessed to produce a desulfurized and denitrogenized low-sulfur, low-ash boiler fuel and a process derived recycle solvent which is recycled to slurry the coal in the beginning of the process before heating.

The milk delivery chain and presence of Brucella spp. antibodies in bulk milk in Uganda.

PubMed

Rock, Kim Toeroek; Mugizi, Denis Rwabiita; Ståhl, Karl; Magnusson, Ulf; Boqvist, Sofia

2016-06-01

This study examined the influence of informal milk delivery chains on the risk of human exposure to Brucella spp. through milk consumption in two regions of Uganda (Gulu and Soroti Districts). The work involved describing milk delivery chains, investigating brucellosis awareness amongst milk deliverers and determining the presence of Brucella spp. antibodies in cattle milk on delivery to primary collection points (boiling points and dairies). Milk samples (n = 331) were collected from deliverers at primary collection points and from street vendors at point of sale and analysed using indirect enzyme-linked immunosorbent assay (I-ELISA). A written questionnaire was used to collect data from deliverers (n = 279) on their milk delivery chains and their brucellosis awareness. The most common delivery points in Gulu District were small dairies and in Soroti District boiling points. The presence of Brucella spp. antibodies in milk samples was higher in Soroti (40 %) than in Gulu (11 %) (P < 0.0001). There are possible public health risk consequences of this finding as 42 % of deliverers in Soroti District reported drinking raw milk, compared with 15 % in Gulu District (P < 0.0001). Awareness of brucellosis was low, with 70 % of all milk deliverers reporting not having heard of the disease or the bacterium. Application of quality controls for milk (colour and odour) along the delivery chain varied depending upon supply and demand. This study provides evidence of the diversity of informal milk markets in low-income countries and of the potential public health risks of consuming unpasteurised milk. These results can be useful to those planning interventions to reduce brucellosis.

Development and Testing of a Novel Standard Particle for Performance Verification of Biodefense/Bioterrorism Detection Systems

DTIC Science & Technology

2003-11-19

Higher boiling point (29.4o F) 39.5 1.36 1,1- difluoroethane HFA 152a – Not used for pharmaceutical inhalers , is used for personal products Boiling...technologies have been implemented. One aspect of this rapid development that has kept biodetection Page 1 Report Documentation Page Form...ApprovedOMB No. 0704-0188 Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for

Chemical Applications of Graph Theory: Part I. Fundamentals and Topological Indices.

ERIC Educational Resources Information Center

Hansen, Peter J.; Jurs, Peter C.

1988-01-01

Explores graph theory and use of topological indices to predict boiling points. Lists three indices: Wiener Number, Randic Branching Index and Molecular Connectivity, and Molecular Identification numbers. Warns of inadequacies with stereochemistry. (ML)

A method for the solvent extraction of low-boiling-point plant volatiles.

PubMed

Xu, Ning; Gruber, Margaret; Westcott, Neil; Soroka, Julie; Parkin, Isobel; Hegedus, Dwayne

2005-01-01

A new method has been developed for the extraction of volatiles from plant materials and tested on seedling tissue and mature leaves of Arabidopsis thaliana, pine needles and commercial mixtures of plant volatiles. Volatiles were extracted with n-pentane and then subjected to quick distillation at a moderate temperature. Under these conditions, compounds such as pigments, waxes and non-volatile compounds remained undistilled, while short-chain volatile compounds were distilled into a receiving flask using a high-efficiency condenser. Removal of the n-pentane and concentration of the volatiles in the receiving flask was carried out using a Vigreux column condenser prior to GC-MS. The method is ideal for the rapid extraction of low-boiling-point volatiles from small amounts of plant material, such as is required when conducting metabolic profiling or defining biological properties of volatile components from large numbers of mutant lines.

New molecular descriptors based on local properties at the molecular surface and a boiling-point model derived from them.

PubMed

Ehresmann, Bernd; de Groot, Marcel J; Alex, Alexander; Clark, Timothy

2004-01-01

New molecular descriptors based on statistical descriptions of the local ionization potential, local electron affinity, and the local polarizability at the surface of the molecule are proposed. The significance of these descriptors has been tested by calculating them for the Maybridge database in addition to our set of 26 descriptors reported previously. The new descriptors show little correlation with those already in use. Furthermore, the principal components of the extended set of descriptors for the Maybridge data show that especially the descriptors based on the local electron affinity extend the variance in our set of descriptors, which we have previously shown to be relevant to physical properties. The first nine principal components are shown to be most significant. As an example of the usefulness of the new descriptors, we have set up a QSPR model for boiling points using both the old and new descriptors.

Highly diverse, massive organic data as explored by a composite QSPR strategy: an advanced study of boiling point.

PubMed

Ivanova, A A; Ivanov, A A; Oliferenko, A A; Palyulin, V A; Zefirov, N S

2005-06-01

An improved strategy of quantitative structure-property relationship (QSPR) studies of diverse and inhomogeneous organic datasets has been proposed. A molecular connectivity term was successively corrected for different structural features encoded in fragmental descriptors. The so-called solvation index 1chis (a weighted Randic index) was used as a "leading" variable and standardized molecular fragments were employed as "corrective" class-specific variables. Performance of the new approach was illustrated by modelling a dataset of experimental normal boiling points of 833 organic compounds belonging to 20 structural classes. Firstly, separate QSPR models were derived for each class and for eight groups of structurally similar classes. Finally, a general model formed by combining all the classes together was derived (r2=0.957, s=12.9degreesC). The strategy outlined can find application in QSPR analyses of massive, highly diverse databases of organic compounds.

Hydroprocessing of rubber seed oil to renewable fuels

NASA Astrophysics Data System (ADS)

Tran, Tan Viet; Phung, Minh Tri

2017-09-01

Hydroprocessing of rubber seed oil (RSO) with various types of alumina-silica support catalyst was conducted at 400°C and a hydrogen partial pressure of 3.0 MPa in 3 hours. The effects of the alumina-silica and metal doping on alumina-silica on the conversion, and distribution of oil fraction products (initial boiling point (IBP) to 80°C, from 80-200°C, from 200-360°C and higher than 360°C boiling point) were investigated. Compared to the results obtained when using Mo@Al2O3-SiO2, hydroprocessing of RSO resulted in a higher conversion and much higher yield of the light fraction (BP <230°C). Both alumina-silica catalysts led to an improved conversion as well as a higher light fraction yield. Results show that hydroprocessing of RSO with metal doping on alumina-silica support was more efficient than that only Al2O3-SiO2.

Vitrification of MSWI Fly Ash by Thermal Plasma Melting and Fate of Heavy Metals

NASA Astrophysics Data System (ADS)

Ni, Guohua; Zhao, Peng; Jiang, Yiman; Meng, Yuedong

2012-09-01

Municipal solid waste incinerator (MSWI) fly ash with high basicity (about 1.68) was vitrified in a thermal plasma melting furnace system. Through the thermal plasma treatment, the vitrified product (slag) with amorphous dark glassy structure was obtained, and the leachability of hazardous metals in slag was significantly reduced. Meanwhile, it was found that the cooling rate affects significantly the immobility of heavy metals in slag. The mass distribution of heavy metals (Zn, Cd, Cr, Pb, As, Hg) was investigated in residual products (slag, secondary residues and flue gas), in order to analyze the behavior of heavy metals in thermal plasma atmosphere. Heavy metal species with low boiling points accounting for the major fraction of their input-mass were adsorbed in secondary residues by pollution abatement devices, while those with high boiling points tended to be encapsulated in slag.

Modeling cooking of chicken meat in industrial tunnel ovens with the Flory-Rehner theory.

PubMed

van der Sman, R G M

2013-12-01

In this paper we present a numerical model describing the heat and mass transport during the cooking of chicken meat in industrial tunnels. The mass transport is driven by gradients in the swelling pressure, which is described by the Flory-Rehner theory, which relates to the water holding capacity (WHC). For cooking temperatures up to boiling point and practical relevant cooking times, the model renders good prediction of heat and mass transport and the total loss of moisture. We have shown that for cooking temperatures above boiling point, the model has to be extended with the dynamic growth of capillary water (drip) channels. Furthermore, we discuss that the Flory-Rehner theory provides the proper physical basis for describing the change of the WHC by a wide variety of factors like salt and pH. Copyright © 2013 Elsevier Ltd. All rights reserved.

Subatmospheric vapor pressures for fluoromethane (R41), 1,1-difluoroethane (R152a), and 1,1,1-trifluoroethane (R143a) evaluated from internal-energy measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duarte-Garza, H.A.; Magee, J.W.

1999-09-01

Vapor pressures were evaluated from measured internal-energy changes {Delta}U{sup (2)} in the vapor + liquid two-phase region. The method employed a thermodynamic relationship between the derivative quantity ({partial_derivative}U{sup (2)}/{partial_derivative}V){sub T}, the vapor pressure p{sub {sigma}}, and its temperature derivative ({partial_derivative}p/{partial_derivative}T){sub {sigma}}. This method was applied at temperatures between the triple point and the normal boiling point of three substances: fluoromethane (R41), 1,1-difluoroethane (R152a), and 1,1,1-trifluoroethane (R143a). In the case of R41, vapor pressures up to 1 MPa were calculated to validate the technique at higher pressures. For R152a, the calculated vapor pressure at the triple-point temperature differed from a directmore » experimental measurement by less than the claimed uncertainty (5 Pa) of the measurement. The calculated vapor pressures for R41 helped to resolve discrepancies in several published vapor pressure sources. Agreement with experimentally measured vapor pressures for R152a and for R143a near the normal boiling point (101.325 kPa) was within the experimental uncertainty of approximately 0.04 kPa (0.04%) for the published measurements.« less

Characterization of the TIP4P-Ew water model: vapor pressure and boiling point.

PubMed

Horn, Hans W; Swope, William C; Pitera, Jed W

2005-11-15

The liquid-vapor-phase equilibrium properties of the previously developed TIP4P-Ew water model have been studied using thermodynamic integration free-energy simulation techniques in the temperature range of 274-400 K. We stress that free-energy results from simulations need to be corrected in order to be compared to the experiment. This is due to the fact that the thermodynamic end states accessible through simulations correspond to fictitious substances (classical rigid liquids and classical rigid ideal gases) while experiments operate on real substances (liquids and real gases, with quantum effects). After applying analytical corrections the vapor pressure curve obtained from simulated free-energy changes is in excellent agreement with the experimental vapor pressure curve. The boiling point of TIP4P-Ew water under ambient pressure is found to be at 370.3+/-1.9 K, about 7 K higher than the boiling point of TIP4P water (363.7+/-5.1 K; from simulations that employ finite range treatment of electrostatic and Lennard-Jones interactions). This is in contrast to the approximately +15 K by which the temperature of the density maximum and the melting temperature of TIP4P-Ew are shifted relative to TIP4P, indicating that the temperature range over which the liquid phase of TIP4P-Ew is stable is narrower than that of TIP4P and resembles more that of real water. The quality of the vapor pressure results highlights the success of TIP4P-Ew in describing the energetic and entropic aspects of intermolecular interactions in liquid water.

Effects of alcohol solvents on anatase TiO2 nanocrystals prepared by microwave-assisted solvothermal method

NASA Astrophysics Data System (ADS)

Wu, Yu-Chun; Tai, Yu-Chuen

2013-06-01

The effects of solvents on the anatase crystallite size prepared by sol-gel microwave-assisted solvothermal method were investigated in this study. Eight different alcohol solvents classified into two groups, i.e. primary and secondary/ternary alcohols, were used as reaction media and the effects of solvent properties, such as dielectric constant, boiling point, and internal pressure during the solvothermal process, on the crystallite size and shape were analyzed. According to the experimental results, selecting the solvent type allowed not only the alteration of the crystallite size but also the crystallite shape without the need of any additives. The boiling point of solvent was determined as the major factor influencing the crystallite size. Among the solvents with similar boiling points, the solvent with a higher carbon number produced the smaller crystallite size because of steric hindrance effect. In addition, the carboxyl groups dissociated from the alcohol solvent can play a role as a structural capping agent to retard the anatase crystal growth along the [001] direction and led to a rectangular crystallite shape with preferred development in {001} facets. On the other hand, the alcoholysis reaction was found easily occurred between the primary alcohol and isopropoxide that effectively limited the hydrolysis and condensation processes but also suppressed the structural capping effect. Therefore, the anatase crystals prepared in the primary alcohols became exceptionally small and showed spherical shape. Finally, the anatase crystals prepared using isopropanol demonstrated the highest photocatalytic activity due to its evident preferred crystallization in the {001} facets.

Study and development of a cryogenic heat exchanger for life support systems

NASA Technical Reports Server (NTRS)

Soliman, M. M.

1973-01-01

A prototype cryogenic heat exchanger for removal of waste heat from a spacecraft environmental control life support system was developed. The heat exchanger uses the heat sink capabilities of the cryogenic propellants and, hence, can operate over all mission phases from prelaunch to orbit, to post landing, with quiescent periods during orbit. A survey of candidate warm fluids resulted in the selection of E-2, a fluorocarbon compound, because of its low freezing point and high boiling point. The final design and testing of the heat exchanger was carried out, however, using Freon-21, which is similar to E-2 except for its low boiling point. This change was motivated by the desire for cost effectiveness of the experimental program. The transient performance of the heat exchanger was demonstrated by an analog simulation of the heat sink system. Under the realistic transient heat load conditions (20 sec ramp from minimum to maximum Freon-21 inlet temperature), the control system was able to maintain the warm fluid outlet temperature within + or - 3 F. For a 20-sec ramp from 0 F to -400 F in the hydrogen inlet temperature, at maximum heat load, the warm fluid outlet temperature was maintained within + or - 7 F.

Corresponding states correlation for temperature dependent surface tension of normal saturated liquids

NASA Astrophysics Data System (ADS)

Yi, Huili; Tian, Jianxiang

2014-07-01

A new simple correlation based on the principle of corresponding state is proposed to estimate the temperature-dependent surface tension of normal saturated liquids. The correlation is a linear one and strongly stands for 41 saturated normal liquids. The new correlation requires only the triple point temperature, triple point surface tension and critical point temperature as input and is able to represent the experimental surface tension data for these 41 saturated normal liquids with a mean absolute average percent deviation of 1.26% in the temperature regions considered. For most substances, the temperature covers the range from the triple temperature to the one beyond the boiling temperature.

Using NMR to Determine the Boiling Point Diagram for a Non-Ideal Solution

ERIC Educational Resources Information Center

Allen, Fritz S.; And Others

1975-01-01

Describes an experiment that enables the student to concentrate on the fundamentals of the non-ideal liquid-vapor equilibrium. Presents typical student data and suggests features which might be added to the experiment. (GS)

Boiling Point

NASA Technical Reports Server (NTRS)

Jansen, Michael C.

2002-01-01

The author recounts his experiences he helped to investigate the accident which destroyed the Space Shuttle Challenger. The focus was on how he used novel approaches to investigate heat transfer in the shuttle's hydrogen tank, after an expert he sought for advice proved unhelpful.

Early Onset of Nucleate Boiling on Gas-covered Biphilic Surfaces.

PubMed

Shen, Biao; Yamada, Masayuki; Hidaka, Sumitomo; Liu, Jiewei; Shiomi, Junichiro; Amberg, Gustav; Do-Quang, Minh; Kohno, Masamichi; Takahashi, Koji; Takata, Yasuyuki

2017-05-17

For phase-change cooling schemes for electronics, quick activation of nucleate boiling helps safeguard the electronics components from thermal shocks associated with undesired surface superheating at boiling incipience, which is of great importance to the long-term system stability and reliability. Previous experimental studies show that bubble nucleation can occur surprisingly early on mixed-wettability surfaces. In this paper, we report unambiguous evidence that such unusual bubble generation at extremely low temperatures-even below the boiling point-is induced by a significant presence of incondensable gas retained by the hydrophobic surface, which exhibits exceptional stability even surviving extensive boiling deaeration. By means of high-speed imaging, it is revealed that the consequently gassy boiling leads to unique bubble behaviour that stands in sharp contrast with that of pure vapour bubbles. Such findings agree qualitatively well with numerical simulations based on a diffuse-interface method. Moreover, the simulations further demonstrate strong thermocapillary flows accompanying growing bubbles with considerable gas contents, which is associated with heat transfer enhancement on the biphilic surface in the low-superheat region.

Dryout-type critical heat flux in vertical upward annular flow: effects of entrainment rate, initial entrained fraction and diameter

NASA Astrophysics Data System (ADS)

Wu, Zan; Wadekar, Vishwas; Wang, Chenglong; Sunden, Bengt

2018-01-01

This study aims to reveal the effects of liquid entrainment, initial entrained fraction and tube diameter on liquid film dryout in vertical upward annular flow for flow boiling. Entrainment and deposition rates of droplets were included in mass conservation equations to estimate the local liquid film mass flux in annular flow, and the critical vapor quality at dryout conditions. Different entrainment rate correlations were evaluated using flow boiling data of water and organic liquids including n-pentane, iso-octane and R134a. Effect of the initial entrained fraction (IEF) at the churn-to-annular flow transition was also investigated. A transitional Boiling number was proposed to separate the IEF-sensitive region at high Boiling numbers and the IEF-insensitive region at low Boiling numbers. Besides, the diameter effect on dryout vapor quality was studied. The dryout vapor quality increases with decreasing tube diameter. It needs to be pointed out that the dryout characteristics of submillimeter channels might be different because of different mechanisms of dryout, i.e., drying of liquid film underneath long vapor slugs and flow boiling instabilities.

Experimental study of the structure of vapor phase during boiling of R134a on heat exchange surfaces of heat pump

NASA Astrophysics Data System (ADS)

Ustinov, D. A.; Sukhikh, A. A.; Sidenkov, D. V.; Ustinov, V. A.

2017-10-01

The heat supply by means of heat pumps is considered now as a rational method of local heating which can lead to economy of primary fuel. At use of low-potential heat, for example, the heat of a ground (5 … 18 °C) or ground waters (8 … 10°C) only small depressing of temperature of these sources (on 3 … 5°C) is possible that demands application of heat exchangers with intensified heatmass transfer surfaces. In thermal laboratory of TOT department the 200 W experimental installation has been developed for research of process of boiling of freon R134a. The principle of action of the installation consists in realisation of reverse thermodynamic cycle and consecutive natural measurement of characteristics of elements of surfaces of heat exchangers of real installations at boiling points of freon from-10°C to +10°C and condensing temperatures from 15°C to 50 °C. The evaporator casing has optical windows for control of process of boiling of freon on ribbed on technology of distorting cut tubes. Temperature measurement in characteristic points of a cycle is provided by copper-constantan thermocouples which by means of ADT are connected to the computer that allows treat results of measurements in a real time mode. The structure of a two-phase flow investigated by means of the optical procedure based on laser technique.

Criticality in the slowed-down boiling crisis at zero gravity.

PubMed

Charignon, T; Lloveras, P; Chatain, D; Truskinovsky, L; Vives, E; Beysens, D; Nikolayev, V S

2015-05-01

Boiling crisis is a transition between nucleate and film boiling. It occurs at a threshold value of the heat flux from the heater called CHF (critical heat flux). Usually, boiling crisis studies are hindered by the high CHF and short transition duration (below 1 ms). Here we report on experiments in hydrogen near its liquid-vapor critical point, in which the CHF is low and the dynamics slow enough to be resolved. As under such conditions the surface tension is very small, the experiments are carried out in the reduced gravity to preserve the conventional bubble geometry. Weightlessness is created artificially in two-phase hydrogen by compensating gravity with magnetic forces. We were able to reveal the fractal structure of the contour of the percolating cluster of the dry areas at the heater that precedes the boiling crisis. We provide a direct statistical analysis of dry spot areas that confirms the boiling crisis at zero gravity as a scale-free phenomenon. It was observed that, in agreement with theoretical predictions, saturated boiling CHF tends to zero (within the precision of our thermal control system) in zero gravity, which suggests that the boiling crisis may be observed at any heat flux provided the experiment lasts long enough.

The Evolution of the Celsius and Kelvin Temperature Scales and the State of the Art

NASA Astrophysics Data System (ADS)

Pellicer, Julio; Amparo Gilabert, M.; Lopez-Baeza, Ernesto

1999-07-01

A physical analysis is given of the evolution undergone by the Celsius and Kelvin temperature scales, from their definition to the present day. It is shown that in the temperature interval between the melting point of ice and the boiling point of water, the Celsius and Kelvin scales, both born centigrade by definition and actually become so afterwards by experimental determination as well, are not so any longer, either by definition or by experimental determination.

Liquid metal heat exchanger for efficient heating of soils and geologic formations

DOEpatents

DeVault, Robert C [Knoxville, TN; Wesolowski, David J [Kingston, TN

2010-02-23

Apparatus for efficient heating of subterranean earth includes a well-casing that has an inner wall and an outer wall. A heater is disposed within the inner wall and is operable within a preselected operating temperature range. A heat transfer metal is disposed within the outer wall and without the inner wall, and is characterized by a melting point temperature lower than the preselected operating temperature range and a boiling point temperature higher than the preselected operating temperature range.

Transpiration Cooled Throat for Hydrocarbon Rocket Engines

DTIC Science & Technology

1991-12-01

entering the oxidizer circuit. Maximum dew point requirement was -500F. The purge pressure provided an oxidizer injector cold-flow pressure of 80 psia...energy bal- ance with the core gas is assumed wherein the heat flux to the annular liquid RP-I layer is equal’ 50 042 0 I- C3 I C30 ME1 M1 49 410 CI... gas generator mixture ratio MW molecular weight NASA/L.RC NASA Lewis Research Center NBP normal boiling point Ni chemical symbol for nickel nom

Use of refinery computer model to predict fuel production

NASA Technical Reports Server (NTRS)

Flores, F. J.

1979-01-01

Several factors (crudes, refinery operation and specifications) that affect yields and properties of broad specification jet fuel were parameterized using the refinery simulation model which can simulate different types of refineries were used to make the calculations. Results obtained from the program are used to correlate yield as a function of final boiling point, hydrogen content and freezing point for jet fuels produced in two refinery configurations, each one processing a different crude mix. Refinery performances are also compared in terms of energy consumption.

Exploring Cryogenic Focused Ion Beam Milling as a Group III-V Device Fabrication Tool

DTIC Science & Technology

2013-09-01

boiling, triple , and critical points of the elements” in CRC Handbook of Chemistry and Physics, 92nd ed., Boca Raton, FL: CRC press, 2011-2012, p. 4...The most widely used ion source in FIB instruments is a gallium (Ga) liquid metal ion source (LMIS) [4]. Gallium is attractive as an ion source...Figure 3b. EDS spectra were captured at different points across the patterned region of the room temperature milled sample, as indicated in Figure 4

Alternative Fuels Data Center: Biodiesel Fuel Basics

Science.gov Websites

gravity 0.88 Kinematic viscosity at 40°C 4.0 to 6.0 Cetane number 47 to 65 Higher heating value, Btu/gal ~127,960 Lower heating value, Btu/gal ~119,550 Density, lb/gal at 15.5°C 7.3 Carbon, wt% 77 Hydrogen, wt % 12 Oxygen, by dif. wt% 11 Boiling point, °C 315-350 Flash point, °C 100-170 Sulfur, wt% 0.0 to

Plastics to fuel: A review

USDA-ARS?s Scientific Manuscript database

This paper reviews recent developments in catalytic and non-catalytic degradation of waste plastics into fuels. Thermal degradation decomposes plastic into three fractions: gas, crude oil, and solid residue. Crude oil from non-catalytic pyrolysis is usually composed of higher boiling point hydrocarb...

Chemistry Notes

ERIC Educational Resources Information Center

School Science Review, 1977

1977-01-01

Includes methods for determining melting and boiling points, illustrating the Finkelstein reaction, choosing acid-base indicators, growing perfect NaC1 cubes and "whiskers," bromination of alkenes, using vanadium in the laboratory, preparing phenylamine-copper (II) sulfate (VI) complex, simulating first-order chemical kinetics on a programmable…

Estimating the melting point, entropy of fusion, and enthalpy of ...

EPA Pesticide Factsheets

The entropies of fusion, enthalies of fusion, and melting points of organic compounds can be estimated through three models developed using the SPARC (SPARC Performs Automated Reasoning in Chemistry) platform. The entropy of fusion is modeled through a combination of interaction terms and physical descriptors. The enthalpy of fusion is modeled as a function of the entropy of fusion, boiling point, and fexibility of the molecule. The melting point model is the enthlapy of fusion divided by the entropy of fusion. These models were developed in part to improve SPARC's vapor pressure and solubility models. These models have been tested on 904 unique compounds. The entropy model has a RMS of 12.5 J mol-1K-1. The enthalpy model has a RMS of 4.87 kJ mol-1. The melting point model has a RMS of 54.4°C. Published in the journal, SAR and QSAR in Environmental Research

Estimating the melting point, entropy of fusion, and enthalpy of fusion of organic compounds via SPARC.

PubMed

Whiteside, T S; Hilal, S H; Brenner, A; Carreira, L A

2016-08-01

The entropy of fusion, enthalpy of fusion, and melting point of organic compounds can be estimated through three models developed using the SPARC (SPARC Performs Automated Reasoning in Chemistry) platform. The entropy of fusion is modelled through a combination of interaction terms and physical descriptors. The enthalpy of fusion is modelled as a function of the entropy of fusion, boiling point, and flexibility of the molecule. The melting point model is the enthalpy of fusion divided by the entropy of fusion. These models were developed in part to improve SPARC's vapour pressure and solubility models. These models have been tested on 904 unique compounds. The entropy model has a RMS of 12.5 J mol(-1) K(-1). The enthalpy model has a RMS of 4.87 kJ mol(-1). The melting point model has a RMS of 54.4°C.

Latest developments in cryogenic safety

NASA Astrophysics Data System (ADS)

Webster, T.

1982-05-01

The Cryogenic Safety Manual, published under the auspices of the British Cryogenics Council, is summarized. Since an awareness of the physical properties of the cryogenic fluids being dealt with is considered important in directing attention to hazardous situations which may arise, the manual lists the more important properties, such as molecular weight, boiling point, and freezing point. Since hydrogen and helium are very light, the possibility arises of explosive mixtures being formed at high points in buildings. Since argon is unexpectedly heavy, its removal requires suction rather than blowing. It is also pointed out that the use of inert liquid nitrogen can lead to the creation of a noninert atmosphere which supports combustion because it contains oxygen. Attention is also given to the danger of asphyxiation posed by the growing use of inert gases.

Giardia and Drinking Water from Private Wells

MedlinePlus

... boiling water is using a point-of-use filter. Not all home water filters remove Giardia . Filters that are designed to remove the parasite should ... learn more, visit CDC’s A Guide to Water Filters page. As you consider ways to disinfect your ...

Influence of boiling point range of feedstock on properties of derived mesophase pitch

NASA Astrophysics Data System (ADS)

Yu, Ran; Liu, Dong; Lou, Bin; Chen, Qingtai; Zhang, Yadong; Li, Zhiheng

2018-06-01

The composition of raw material was optimized by vacuum distillation. The carbonization behavior of two kinds of raw material was followed by polarizing microscope, softening point, carbon yield and solubility. Two kinds of mesophase pitch have been monitored by X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), elemental analysis and 1H nuclear magnetic resonance (1H-NMR). The analysis results suggested that raw material B (15wt% of A was distillated out and the residue named B) could form large domain mesophase pitch earlier. The shortened heat treat time favored the retaining of alkyl group in mesophase pitch and reduced the softening point of masophase pitch.

Optical constants of liquid and solid methane

NASA Technical Reports Server (NTRS)

Martonchik, John V.; Orton, Glenn S.

1994-01-01

The optical constants n(sub r) + in(sub i) of liquid methane and phase 1 solid methane were determined over the entire spectral range by the use of various data sources published in the literature. Kramers-Kronig analyses were performed on the absorption spectra of liquid methane at the boiling point (111 K) and the melting point (90 K) and on the absorption spectra of phase 1 solid methane at the melting point and at 30 K. Measurements of the static dielectric constant at these temperatures and refractive indices determined over limited spectral ranges were used as constraints in the analyses. Applications of methane optical properties to studies of outer solar system bodies are described.

Nuclear-coupled thermal-hydraulic stability analysis of boiling water reactors

NASA Astrophysics Data System (ADS)

Karve, Atul A.

We have studied the nuclear-coupled thermal-hydraulic stability of boiling water reactors (BWRs) using a model we developed from: the space-time modal neutron kinetics equations based on spatial omega-modes, the equations for two-phase flow in parallel boiling channels, the fuel rod heat conduction equations, and a simple model for the recirculation loop. The model is represented as a dynamical system comprised of time-dependent nonlinear ordinary differential equations, and it is studied using stability analysis, modern bifurcation theory, and numerical simulations. We first determine the stability boundary (SB) in the most relevant parameter plane, the inlet-subcooling-number/external-pressure-drop plane, for a fixed control rod induced external reactivity equal to the 100% rod line value and then transform the SB to the practical power-flow map. Using this SB, we show that the normal operating point at 100% power is very stable, stability of points on the 100% rod line decreases as the flow rate is reduced, and that points are least stable in the low-flow/high-power region. We also determine the SB when the modal kinetics is replaced by simple point reactor kinetics and show that the first harmonic mode has no significant effect on the SB. Later we carry out the relevant numerical simulations where we first show that the Hopf bifurcation, that occurs as a parameter is varied across the SB is subcritical, and that, in the important low-flow/high-power region, growing oscillations can result following small finite perturbations of stable steady-states on the 100% rod line. Hence, a point on the 100% rod line in the low-flow/high-power region, although stable, may nevertheless be a point at which a BWR should not be operated. Numerical simulations are then done to calculate the decay ratios (DRs) and frequencies of oscillations for various points on the 100% rod line. It is determined that the NRC requirement of DR < 0.75-0.8 is not rigorously satisfied in the low-flow/high-power region and hence these points should be avoided during normal startup and shutdown operations. The frequency of oscillation is shown to decrease as the flow rate is reduced and the frequency of 0.5Hz observed in the low-flow/high-power region is consistent with those observed during actual instability incidents. Additional numerical simulations show that in the low-flow/high-power region, for the same initial conditions, the use of point kinetics leads to damped oscillations, whereas the model that includes the modal kinetics equations results in growing nonlinear oscillations. Thus, we show that side-by-side out-of-phase growing power oscillations result due to the very important first harmonic mode effect and that the use of point kinetics, which fails to predict these growing oscillations, leads to dramatically nonconservative results. Finally, the effect of a simple recirculation loop model that we develop is studied by carrying out additional stability analyses and additional numerical simulations. It is shown that the loop has a stabilizing effect on certain points on the 100% rod line for time delays equal to integer multiples of the natural period of oscillation, whereas it has a destabilizing effect for half-integer multiples. However, for more practical time delays, it is determined that the overall effect generally is destabilizing.

EVALUATION OF ROTARY KILN INCINERATOR OPERATION AT LOW TO MODERATE TEMPERATURE CONDITIONS VOLUME 1. TECHNICAL RESULTS

EPA Science Inventory

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...

A Simplified Apparatus for Ebullioscopic Measurements of Air/Moisture Sensitive Compounds.

ERIC Educational Resources Information Center

Bulkin, Bernard J.; Tergis, Paul

1979-01-01

An ebullioscopic apparatus is described in which only the difference between the boiling point of the solution and that of the pure solvent is measured. This substantially reduces the cost of the apparatus and simplifies the operation, while maintaining precision. (BB)

Anhydrous hydrogen fluoride electrolyte battery. [Patent application

DOEpatents

Not Available

1972-06-26

It is an object of the invention to provide a primary cell or battery using ammonium fluoride--anhydrous hydrogen fluoride electrolyte having improved current and power production capabilities at low temperatures. It is operable at temperatures substantially above the boiling point of hydrogen fluoride. (GRA)

Elementary Science Notes

ERIC Educational Resources Information Center

School Science Review, 1973

1973-01-01

Ideas for elementary school teachers are proposed. Demonstration experiments include thermal conductivity of gases, wetting power of detergents, external pressure effects on boiling point of water, frequency-wavelength relations, density of hot and cold water. Other useful tips are given for protecting wall charts and making descriptive labels.…

VOLATILE ORGANIC COMPOUND DETERMINATIONS USING SURROGATE-BASED CORRECTION FOR METHOD AND MATRIX EFFECTS

EPA Science Inventory

The principal properties related to analyte recovery in a vacuum distillate are boiling point and relative volatility. The basis for selecting compounds to measure the relationship between these properties and recovery for a vacuum distillation is presented. Surrogates are incorp...

Below and above boiling point comparison of microwave irradiation and conductive heating for municipal sludge digestion under identical heating/cooling profiles.

PubMed

Hosseini Koupaie, E; Eskicioglu, C

2015-01-01

This research provides a comprehensive comparison between microwave (MW) and conductive heating (CH) sludge pretreatments under identical heating/cooling profiles at below and above boiling point temperatures. Previous comparison studies were constrained to an uncontrolled or a single heating rate due to lack of a CH equipment simulating MW under identical thermal profiles. In this research, a novel custom-built pressure-sealed vessel which could simulate MW pretreatment under identical heating/cooling profiles was used for CH pretreatment. No statistically significant difference was proven between MW and CH pretreatments in terms of sludge solubilization, anaerobic biogas yield and organics biodegradation rate (p-value>0.05), while statistically significant effects of temperature and heating rate were observed (p-value<0.05). These results explain the contradictory results of previous studies in which only the final temperature (not heating/cooling rates) was controlled. Copyright © 2015 Elsevier Ltd. All rights reserved.

High-yield exfoliation of tungsten disulphide nanosheets by rational mixing of low-boiling-point solvents

NASA Astrophysics Data System (ADS)

Sajedi-Moghaddam, Ali; Saievar-Iranizad, Esmaiel

2018-01-01

Developing high-throughput, reliable, and facile approaches for producing atomically thin sheets of transition metal dichalcogenides is of great importance to pave the way for their use in real applications. Here, we report a highly promising route for exfoliating two-dimensional tungsten disulphide sheets by using binary combination of low-boiling-point solvents. Experimental results show significant dependence of exfoliation yield on the type of solvents as well as relative volume fraction of each solvent. The highest yield was found for appropriate combination of isopropanol/water (20 vol% isopropanol and 80 vol% water) which is approximately 7 times higher than that in pure isopropanol and 4 times higher than that in pure water. The dramatic increase in exfoliation yield can be attributed to perfect match between the surface tension of tungsten disulphide and binary solvent system. Furthermore, solvent molecular size also has a profound impact on the exfoliation efficiency, due to the steric repulsion.

Prior-knowledge-based feedforward network simulation of true boiling point curve of crude oil.

PubMed

Chen, C W; Chen, D Z

2001-11-01

Theoretical results and practical experience indicate that feedforward networks can approximate a wide class of functional relationships very well. This property is exploited in modeling chemical processes. Given finite and noisy training data, it is important to encode the prior knowledge in neural networks to improve the fit precision and the prediction ability of the model. In this paper, as to the three-layer feedforward networks and the monotonic constraint, the unconstrained method, Joerding's penalty function method, the interpolation method, and the constrained optimization method are analyzed first. Then two novel methods, the exponential weight method and the adaptive method, are proposed. These methods are applied in simulating the true boiling point curve of a crude oil with the condition of increasing monotonicity. The simulation experimental results show that the network models trained by the novel methods are good at approximating the actual process. Finally, all these methods are discussed and compared with each other.

The mixing effects for real gases and their mixtures

NASA Astrophysics Data System (ADS)

Gong, M. Q.; Luo, E. C.; Wu, J. F.

2004-10-01

The definitions of the adiabatic and isothermal mixing effects in the mixing processes of real gases were presented in this paper. Eight substances with boiling-point temperatures from cryogenic temperature to the ambient temperature were selected from the interest of low temperature refrigeration to study their binary and multicomponent mixing effects. Detailed analyses were made on the parameters of the mixing process to know their influences on mixing effects. Those parameters include the temperatures, pressures, and mole fraction ratios of pure substances before mixing. The results show that the maximum temperature variation occurs at the saturation state of each component in the mixing process. Those components with higher boiling-point temperatures have higher isothermal mixing effects. The maximum temperature variation which is defined as the adiabatic mixing effect can even reach up to 50 K, and the isothermal mixing effect can reach about 20 kJ/mol. The possible applications of the mixing cooling effect in both open cycle and closed cycle refrigeration systems were also discussed.

Ultrahigh thermoelectric power factor in flexible hybrid inorganic-organic superlattice

DOE PAGES

Wan, Chunlei; Tian, Ruoming; Kondou, Mami; ...

2017-10-18

Hybrid inorganic–organic superlattice with an electron-transmitting but phonon-blocking structure has emerged as a promising flexible thin film thermoelectric material. However, the substantial challenge in optimizing carrier concentration without disrupting the superlattice structure prevents further improvement of the thermoelectric performance. Here we demonstrate a strategy for carrier optimization in a hybrid inorganic–organic superlattice of TiS 2[tetrabutylammonium] x [hexylammonium] y, where the organic layers are composed of a random mixture of tetrabutylammonium and hexylammonium molecules. By vacuum heating the hybrid materials at an intermediate temperature, the hexylammonium molecules with a lower boiling point are selectively de-intercalated, which reduces the electron density duemore » to the requirement of electroneutrality. The tetrabutylammonium molecules with a higher boiling point remain to support and stabilize the superlattice structure. Furthermore, the carrier concentration can thus be effectively reduced, resulting in a remarkably high power factor of 904 µW m –1 K –2 at 300 K for flexible thermoelectrics, approaching the values achieved in conventional inorganic semiconductors.« less

Controlled chemical stabilization of polyvinyl precursor fiber, and high strength carbon fiber produced therefrom

DOEpatents

Naskar, Amit K.

2016-12-27

Method for the preparation of carbon fiber, which comprises: (i) immersing functionalized polyvinyl precursor fiber into a liquid solution having a boiling point of at least 60.degree. C.; (ii) heating the liquid solution to a first temperature of at least 25.degree. C. at which the functionalized precursor fiber engages in an elimination-addition equilibrium while a tension of at least 0.1 MPa is applied to the fiber; (iii) gradually raising the first temperature to a final temperature that is at least 20.degree. C. above the first temperature and up to the boiling point of the liquid solution for sufficient time to convert the functionalized precursor fiber to a pre-carbonized fiber; and (iv) subjecting the pre-carbonized fiber produced according to step (iii) to high temperature carbonization conditions to produce the final carbon fiber. Articles and devices containing the fibers, including woven and non-woven mats or paper forms of the fibers, are also described.

Ultrahigh thermoelectric power factor in flexible hybrid inorganic-organic superlattice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wan, Chunlei; Tian, Ruoming; Kondou, Mami

Hybrid inorganic–organic superlattice with an electron-transmitting but phonon-blocking structure has emerged as a promising flexible thin film thermoelectric material. However, the substantial challenge in optimizing carrier concentration without disrupting the superlattice structure prevents further improvement of the thermoelectric performance. Here we demonstrate a strategy for carrier optimization in a hybrid inorganic–organic superlattice of TiS 2[tetrabutylammonium] x [hexylammonium] y, where the organic layers are composed of a random mixture of tetrabutylammonium and hexylammonium molecules. By vacuum heating the hybrid materials at an intermediate temperature, the hexylammonium molecules with a lower boiling point are selectively de-intercalated, which reduces the electron density duemore » to the requirement of electroneutrality. The tetrabutylammonium molecules with a higher boiling point remain to support and stabilize the superlattice structure. Furthermore, the carrier concentration can thus be effectively reduced, resulting in a remarkably high power factor of 904 µW m –1 K –2 at 300 K for flexible thermoelectrics, approaching the values achieved in conventional inorganic semiconductors.« less

Consumers' perception and acceptance of boiled and fermented sausages from strongly boar tainted meat.

PubMed

Meier-Dinkel, Lisa; Gertheiss, Jan; Schnäckel, Wolfram; Mörlein, Daniel

2016-08-01

Characteristic off-flavours may occur in uncastrated male pigs depending on the accumulation of androstenone and skatole. Feasible processing of strongly tainted carcasses is challenging but gains in importance due to the European ban on piglet castration in 2018. This paper investigates consumers' acceptability of two sausage types: (a) emulsion-type (BOILED) and (b) smoked raw-fermented (FERM). Liking (9 point scales) and flavour perception (check-all-that-apply with both, typical and negatively connoted sensory terms) were evaluated by 120 consumers (within-subject design). Proportion of tainted boar meat (0, 50, 100%) affected overall liking of BOILED, F (2, 238)=23.22, P<.001, but not of FERM sausages, F (2, 238)=0.89, P=.414. Consumers described the flavour of BOILED-100 as strong and sweaty. In conclusion, FERM products seem promising for processing of tainted carcasses whereas formulations must be optimized for BOILED in order to eliminate perceptible off-flavours. Boar taint rejection thresholds may be higher for processed than those suggested for unprocessed meat cuts. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Role of Bulk Additions in Solid Lubricant Compacts

DTIC Science & Technology

1987-04-01

compact Surface ............. 138 36. Wear Volume as a Function of Kohn Hardness.... 161 37. Melt Temperature of Oxides as Function of Kohs Hardness...PROPERTIES OF ANTIMONY AND ANTIMONY OXIDES ELEMENT OR FORMULA FORMULA CRYSTAL SP MELT BOILING COMPOUND WEIGHT FORM GRAY POINT POINT (C0 (00 Antimony...be rationalized as oxidation of smaller particle size Sb203(o) followed by melting and, 84 .40 00 0 o0 40 an M a CA 𔃺o 0u 1 "M OX3 ---- fýO’N Pý > 85

46 CFR 98.25-20 - Installation of cargo tanks.

Code of Federal Regulations, 2014 CFR

2014-10-01

... CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk... installed with the manhole opening and fittings located above the weather deck. (d) The anhydrous ammonia... anhydrous ammonia tanks complies with the following chemical and physical properties: (1) Boiling point...

46 CFR 98.25-20 - Installation of cargo tanks.

Code of Federal Regulations, 2010 CFR

2010-10-01

... CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk... installed with the manhole opening and fittings located above the weather deck. (d) The anhydrous ammonia... anhydrous ammonia tanks complies with the following chemical and physical properties: (1) Boiling point...

46 CFR 98.25-20 - Installation of cargo tanks.

Code of Federal Regulations, 2011 CFR

2011-10-01

... CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk... installed with the manhole opening and fittings located above the weather deck. (d) The anhydrous ammonia... anhydrous ammonia tanks complies with the following chemical and physical properties: (1) Boiling point...

46 CFR 98.25-20 - Installation of cargo tanks.

Code of Federal Regulations, 2013 CFR

2013-10-01

... CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk... installed with the manhole opening and fittings located above the weather deck. (d) The anhydrous ammonia... anhydrous ammonia tanks complies with the following chemical and physical properties: (1) Boiling point...

46 CFR 98.25-20 - Installation of cargo tanks.

Code of Federal Regulations, 2012 CFR

2012-10-01

... CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk... installed with the manhole opening and fittings located above the weather deck. (d) The anhydrous ammonia... anhydrous ammonia tanks complies with the following chemical and physical properties: (1) Boiling point...

Using Molecular Dynamics Simulation to Reinforce Student Understanding of Intermolecular Forces

ERIC Educational Resources Information Center

Burkholder, Phillip R.; Purser, Gordon H.; Cole, Renee S.

2008-01-01

Intermolecular forces play an important role in many aspects of chemistry ranging from inorganic to biological chemistry. These forces dictate molecular conformation, species aggregation (including self-assembly), trends in solubility and boiling points, adsorption characteristics, viscosity, phase changes, surface tension, capillary action, vapor…

Thermal dissolution of maize starches in aqueous medium

USDA-ARS?s Scientific Manuscript database

Starches are not soluble in neutral water at room temperature. However, if they are heated in a closed container beyond the boiling point of water, they eventually dissolve. The dissolution temperature depends on the type of starch. The dissolution process was monitored in real time by measuring ...

PREDICTION OF THE VAPOR PRESSURE, BOILING POINT, HEAT OF VAPORIZATION AND DIFFUSION COEFFICIENT OF ORGANIC COMPOUNDS

EPA Science Inventory

The prototype computer program SPARC has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC solute-solute physical process models have been developed and tested...

21 CFR 172.882 - Synthetic isoparaffinic petroleum hydrocarbons.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Synthetic isoparaffinic petroleum hydrocarbons... hydrocarbons. Synthetic isoparaffinic petroleum hydrocarbons may be safely used in food, in accordance with the... liquid hydrocarbons meeting the following specifications: Boiling point 93-260 °C as determined by ASTM...

Activity ratios in soil contaminated by the source of different reactor condition in the FDNPP accident

NASA Astrophysics Data System (ADS)

Satou, Yukihiko; Sueki, Keisuke; Sasa, Kimikazu; Matsunaka, Tetsuya; Shibayama, Nao; Takahashi, Tsutomu; Kinoshita, Norikazu

2014-05-01

The Fukushima Dai-ichi Nuclear power plant (FDNPP) accident caused radioactive contamination on the surface soil at Fukushima and its adjacent prefectures. Substantial contamination has been found in the northwestern area from the FDNPP, according to the airborne monitoring and ground base survey by the Japanese government. Activity ratios would have characteristic information on emission sources because each relevant reactor had different amount of radionuclide and different activity ratio. The ratios can be used to clarify more detailed source and process in the contamination. We have addressed to consider them in Namie town, northwestern region from the FDNPP. This study focused on the gamma-ray emitting radionuclides of 134Cs, 137Cs, and 110mAg. The activities were decay-corrected as of 11th March, 2011 when all nuclear reactors scrammed. Data of activity ratios by our results and the Japanese official report classified the investigated northwestern region into 3 groups. Ratios of 0.02 for 110mAg/137Cs and 0.90 for 134Cs/137Cs were observed in the northern region of 15 km inside from the FDNPP. On the other hand, two kinds of 110mAg/137Cs ratios of 0.005 and 0.002 were distributed broadly in the region 60 km away from the plant. The 134Cs/137Cs ratio was 0.98 there. The activity ratios of 110mAg/137Cs and 134Cs/137Cs in the northern region from the FDNPP correspond to those of nuclear fuel in Unit 1 according to estimation using the ORIGEN code. The 134Cs/137Cs in the northwestern area from FDNPP agrees with that of Unit 2 and 3. The 110mAg/137Cs ratios of 0.005 and0.002 are 1/5 - 1/10 of the Unit 2 and 3. Official report has announced that discharges of the radionuclides from Unit 2 and 3 occurred on 14th March, 2011. It is known that contamination in the northwestern region from the FDNPP took place on 15th March, 2011. Plausible species for silver in reactor core, metal, and halide etc. have higher boiling point than those species for cesium. The core would be cooled down to lower temperature of the boiling point of silver at the timing contamination occurred. Thus, silver with higher boiling point was not much released than cesium with lower boiling point. The 110mAg/137Cs ratio has served to identify the specific sources of contamination in the northwestern area from the FDNPP.

Changes provoked by boiling, steaming and sous-vide cooking in the lipid and volatile profile of European sea bass.

PubMed

Nieva-Echevarría, Bárbara; Manzanos, María J; Goicoechea, Encarnación; Guillén, María D

2017-09-01

This study aims to shed light on the changes provoked by boiling, steaming and sous-vide cooking on the lipids and volatile profile of farmed and wild European sea bass meat. None of the cooking techniques provoked changes due to hydrolytic or oxidation processes detectable by 1 H NMR on sea bass lipids. The lipid profile of main and minor lipidic components was maintained after cooking. However, study by SPME-GC/MS evidenced that steaming and sous-vide cooking modified the volatile profile of sea bass meat, especially in farmed specimens. The compounds generated came from the occurrence, to a very small extent, of lipid and protein degradation. By contrast, boiling scarcely modified the initial characteristics of raw sea bass. Thus, from a sensory point of view and considering the odour-active compounds generated, steaming and sous-vide cooking provoked more noticeable changes than boiling, especially in farmed sea bass meat. Copyright © 2017. Published by Elsevier Ltd.

Microbiological effectiveness and cost of disinfecting water by boiling in semi-urban India.

PubMed

Clasen, Thomas; McLaughlin, Catherine; Nayaar, Neeru; Boisson, Sophie; Gupta, Romesh; Desai, Dolly; Shah, Nimish

2008-09-01

Despite shortcomings, boiling is the most common means of treating water at home and the benchmark against which emerging point-of-use water treatment approaches are measured. In a 5-month study, we assessed the microbiological effectiveness and cost of the practice among 218 self-reported boilers relying on unprotected water supplies. Boiling was associated with a 99% reduction in geometric mean fecal coliforms (FCs; P < 0.001). Despite high levels of fecal contamination in source water, 59.6% of stored drinking water samples from self-reported boilers met the World Health Organization standard for safe drinking water (0 FC/100 mL), and 5.7% were between 1 and 10 FC/100 mL. Nevertheless, 40.4% of stored drinking water samples were positive for FCs, with 25.1% exceeding 100 FC/100 mL. The estimated monthly fuel cost for boiling was INR 43.8 (US$0.88) for households using liquid petroleum gas and INR 34.7 (US$0.69) for households using wood.

Boiling point.

PubMed

Newnham, David

2012-07-04

How much tea is too much? How many cuppas are a couple too many? Researchers at Glasgow University, who tracked the health of 6,000 men for 37 years, found that those who drank more than seven cups a day were 50 per cent more likely to develop prostate cancer than those who did not.

Molecular Association and Structure of Hydrogen Peroxide.

ERIC Educational Resources Information Center

Giguere, Paul A.

1983-01-01

The statement is sometimes made in textbooks that liquid hydrogen peroxide is more strongly associated than water, evidenced by its higher boiling point and greater heat of vaporization. Discusses these and an additional factor (the nearly double molecular mass of the peroxide), focusing on hydrogen bonds and structure of the molecule. (JN)

Students' Understanding of Molecular Structure and Properties of Organic Compounds.

ERIC Educational Resources Information Center

Schmidt, Hans-Jurgen

The purpose of this study was to investigate senior high school students' difficulties predicting the existence of hydrogen bridge bonds between organic molecules, investigate students' difficulties predicting the relative boiling points of simple organic compounds, and develop test questions that enable teachers to quickly get information about…

On the Boiling Points of the Alkyl Halides.

ERIC Educational Resources Information Center

Correia, John

1988-01-01

Discusses the variety of explanations in organic chemistry textbooks of a physical property of organic compounds. Focuses on those concepts explaining attractive forces between molecules. Concludes that induction interactions play a major role in alkyl halides and other polar organic molecules and should be given wider exposure in chemistry texts.…

7. View showing placement of timber deck placement on chord ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. View showing placement of timber deck placement on chord and built up construction of top chord and continuous construction through top panel points, eye bar construction on bottom chord - Bridge No. 2.4, Spanning Boiling Fork Creek at Railroad Milepost JC-2.4, Decherd, Franklin County, TN

46 CFR 154.7 - Definitions, acronyms, and terms.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Chapter II-2 of the 1974 Safety Convention. Accommodation spaces means public spaces, corridors... appliances, and spaces used in a similar fashion. Boiling point means the temperature at which a substance's... include the cofferdams, ballast spaces, or void spaces at the after end of the aftermost hold space or the...

46 CFR 154.7 - Definitions, acronyms, and terms.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Chapter II-2 of the 1974 Safety Convention. Accommodation spaces means public spaces, corridors... appliances, and spaces used in a similar fashion. Boiling point means the temperature at which a substance's... include the cofferdams, ballast spaces, or void spaces at the after end of the aftermost hold space or the...

46 CFR 154.7 - Definitions, acronyms, and terms.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Chapter II-2 of the 1974 Safety Convention. Accommodation spaces means public spaces, corridors... appliances, and spaces used in a similar fashion. Boiling point means the temperature at which a substance's... include the cofferdams, ballast spaces, or void spaces at the after end of the aftermost hold space or the...

46 CFR 154.7 - Definitions, acronyms, and terms.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Chapter II-2 of the 1974 Safety Convention. Accommodation spaces means public spaces, corridors... appliances, and spaces used in a similar fashion. Boiling point means the temperature at which a substance's... include the cofferdams, ballast spaces, or void spaces at the after end of the aftermost hold space or the...

Fuel and fuel blending components from biomass derived pyrolysis oil

DOEpatents

McCall, Michael J.; Brandvold, Timothy A.; Elliott, Douglas C.

2012-12-11

A process for the conversion of biomass derived pyrolysis oil to liquid fuel components is presented. The process includes the production of diesel, aviation, and naphtha boiling point range fuels or fuel blending components by two-stage deoxygenation of the pyrolysis oil and separation of the products.

40 CFR 63.6675 - What definitions apply to this subpart?

Code of Federal Regulations, 2012 CFR

2012-07-01

... for use during periods of high demand that are not emergencies. Percent load means the fractional... stationary RICE in which a high boiling point liquid fuel injected into the combustion chamber ignites when the air charge has been compressed to a temperature sufficiently high for auto-ignition. This process...

Preliminary analysis of aircraft fuel systems for use with broadened specification jet fuels

NASA Technical Reports Server (NTRS)

Pasion, A. J.; Thomas, I.

1977-01-01

An analytical study was conducted on the use of broadened specification hydrocarbon fuels in present day aircraft. A short range Boeing 727 mission and three long range Boeing 747 missions were used as basis of calculation for one-day-per-year extreme values of fuel loading, airport ambient and altitude ambient temperatures with various seasonal and climatic conditions. Four hypothetical fuels were selected; two high-vapor-pressure fuels with 35 kPa and 70 kPa RVP and two high-freezing-point fuels with -29 C and -18 C freezing points. In-flight fuel temperatures were predicted by Boeing's aircraft fuel tank thermal analyzer computer program. Boil-off rates were calculated for the high vapor pressure fuels and heating/insulation requirements for the high freezing point fuels were established. Possible minor and major heating system modifications were investigated with respect to heat output, performance and economic penalties for the high freezing point fuels.

Flash Points of Secondary Alcohol and n-Alkane Mixtures.

PubMed

Esina, Zoya N; Miroshnikov, Alexander M; Korchuganova, Margarita R

2015-11-19

The flash point is one of the most important characteristics used to assess the ignition hazard of mixtures of flammable liquids. To determine the flash points of mixtures of secondary alcohols with n-alkanes, it is necessary to calculate the activity coefficients. In this paper, we use a model that allows us to obtain enthalpy of fusion and enthalpy of vaporization data of the pure components to calculate the liquid-solid equilibrium (LSE) and vapor-liquid equilibrium (VLE). Enthalpy of fusion and enthalpy of vaporization data of secondary alcohols in the literature are limited; thus, the prediction of these characteristics was performed using the method of thermodynamic similarity. Additionally, the empirical models provided the critical temperatures and boiling temperatures of the secondary alcohols. The modeled melting enthalpy and enthalpy of vaporization as well as the calculated LSE and VLE flash points were determined for the secondary alcohol and n-alkane mixtures.

Development of a screening tool to prioritize testing for the carcinogenic hazard of residual aromatic extracts and related petroleum streams.

PubMed

Goyak, Katy O; Kung, Ming H; Chen, Min; Aldous, Keith K; Freeman, James J

2016-12-15

Residual aromatic extracts (RAE) are petroleum substances with variable composition predominantly containing aromatic hydrocarbons with carbon numbers greater than C25. Because of the high boiling nature of RAEs, the aromatics present are high molecular weight, with most above the range of carcinogenic polycyclic aromatic hydrocarbons (PAHs). However, refinery distillations are imperfect; some PAHs and their heteroatom-containing analogs (collectively referred to as polycyclic aromatic content or PAC) may remain in the parent stream and be extracted into the RAE, and overall PAC content is related to the carcinogenic potential of an RAE. We describe here a real-time analytical chemistry-based tool to assess the carcinogenic hazard of RAE via the development of a functional relationship between carcinogenicity and boiling point. Samples representative of steps along the RAE manufacturing process were obtained from five refineries to evaluate relationships between mutagenicity index (MI), PAC ring content and gas chromatographic distillation (GCD) curves. As expected, a positive linear relationship between MI and PAC ring content occurred, most specifically for 3-6 ring PAC (R 2 =0.68). A negative correlation was found between MI and temperature at 5% vaporization by GCD (R 2 =0.72), indicating that samples with greater amounts of lower boiling constituents were more likely to be carcinogenic. The inverse relationship between boiling range and carcinogenicity was further demonstrated by fractionation of select RAE samples (MI=0.50+0.07; PAC=1.70+0.51wt%; n=5) into low and high boiling fractions, where lower boiling fractions were both more carcinogenic than the higher boiling fractions (MI=2.36±0.55 and 0.17±0.11, respectively) and enriched in 3-6 ring PACs (5.20+0.70wt% and 0.97+0.35wt%, respectively). The criteria defining carcinogenicity was established as 479°C for the 5% vaporization points by GCD, with an approximate 95% probability of a future sample having an MI below the recommended limit of 0.4 for RAEs. Overall, these results provide a cost-efficient and real-time tool by which the carcinogenic potential of RAEs can be assessed at the refinery level, ultimately providing a means to readily monitor and minimize the carcinogenic potential of RAEs. Copyright © 2016. Published by Elsevier Ireland Ltd.

Methods of cracking a crude product to produce additional crude products

DOEpatents

Mo, Weijian [Sugar Land, TX; Roes, Augustinus Wilhelmus Maria [Houston, TX; Nair, Vijay [Katy, TX

2009-09-08

A method for producing a crude product is disclosed. Formation fluid is produced from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. The liquid stream is fractionated to produce one or more crude products. At least one of the crude products has a boiling range distribution from 38.degree. C. and 343.degree. C. as determined by ASTM Method D5307. The crude product having the boiling range distribution from 38.degree. C. and 343.degree. C. is catalytically cracked to produce one or more additional crude products. At least one of the additional crude products is a second gas stream. The second gas stream has a boiling point of at most 38.degree. C. at 0.101 MPa.

Fluid inclusion from drill hole DW-5, Hohi geothermal area, Japan: Evidence of boiling and procedure for estimating CO2 content

USGS Publications Warehouse

Sasada, M.; Roedder, E.; Belkin, H.E.

1986-01-01

Fluid inclusion studies have been used to derive a model for fluid evolution in the Hohi geothermal area, Japan. Six types of fluid inclusions are found in quartz obtained from the drill core of DW-5 hole. They are: (I) primary liquid-rich with evidence of boiling; (II) primary liquid-rich without evidence of boiling; (III) primary vapor-rich (assumed to have been formed by boiling); (IV) secondary liquid-rich with evidence of boiling; (V) secondary liquid-rich without evidence of boiling; (VI) secondary vapor-rich (assumed to have been formed by boiling). Homogenization temperatures (Th) range between 196 and 347??C and the final melting point of ice (Tm) between -0.2 and -4.3??C. The CO2 content was estimated semiquantitatively to be between 0 and 0.39 wt. % based on the bubble behavior on crushing. NaCl equivalent solid solute salinity of fluid inclusions was determined as being between 0 and 6.8 wt. % after minor correction for CO2 content. Fluid inclusions in quartz provide a record of geothermal activity of early boiling and later cooling. The CO2 contents and homogenization temperatures of fluid inclusions with evidence of boiling generally increase with depth; these changes, and NaCl equivalent solid solute salinity of the fluid can be explained by an adiabatic boiling model for a CO2-bearing low-salinity fluid. Some high-salinity inclusions without CO2 are presumed to have formed by a local boiling process due to a temperature increase or a pressure decrease. The liquid-rich primary and secondary inclusions without evidence of boiling formed during the cooling process. The salinity and CO2 content of these inclusions are lower than those in the boiling fluid at the early stage, probably as a result of admixture with groundwater. ?? 1986.

A low viscosity, low boiling point, clean solvent system for the rapid crystallisation of highly specular perovskite films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Noel, Nakita K.; Habisreutinger, Severin N.; Wenger, Bernard

2017-01-01

Perovskite-based photovoltaics have, in recent years, become poised to revolutionise the solar industry. While there have been many approaches taken to the deposition of this material, one-step spin-coating remains the simplest and most widely used method in research laboratories. Although spin-coating is not recognised as the ideal manufacturing methodology, it represents a starting point from which more scalable deposition methods, such as slot-dye coating or ink-jet printing can be developed. Here, we introduce a new, low-boiling point, low viscosity solvent system that enables rapid, room temperature crystallisation of methylammonium lead triiodide perovskite films, without the use of strongly coordinating aproticmore » solvents. Through the use of this solvent, we produce dense, pinhole free films with uniform coverage, high specularity, and enhanced optoelectronic properties. We fabricate devices and achieve stabilised power conversion efficiencies of over 18% for films which have been annealed at 100 degrees C, and over 17% for films which have been dried under vacuum and have undergone no thermal processing. This deposition technique allows uniform coating on substrate areas of up to 125 cm2, showing tremendous promise for the fabrication of large area, high efficiency, solution processed devices, and represents a critical step towards industrial upscaling and large area printing of perovskite solar cells.« less

Thermodynamics and proton activities of protic ionic liquids with quantum cluster equilibrium theory

NASA Astrophysics Data System (ADS)

Ingenmey, Johannes; von Domaros, Michael; Perlt, Eva; Verevkin, Sergey P.; Kirchner, Barbara

2018-05-01

We applied the binary Quantum Cluster Equilibrium (bQCE) method to a number of alkylammonium-based protic ionic liquids in order to predict boiling points, vaporization enthalpies, and proton activities. The theory combines statistical thermodynamics of van-der-Waals-type clusters with ab initio quantum chemistry and yields the partition functions (and associated thermodynamic potentials) of binary mixtures over a wide range of thermodynamic phase points. Unlike conventional cluster approaches that are limited to the prediction of thermodynamic properties, dissociation reactions can be effortlessly included into the bQCE formalism, giving access to ionicities, as well. The method is open to quantum chemical methods at any level of theory, but combination with low-cost composite density functional theory methods and the proposed systematic approach to generate cluster sets provides a computationally inexpensive and mostly parameter-free way to predict such properties at good-to-excellent accuracy. Boiling points can be predicted within an accuracy of 50 K, reaching excellent accuracy for ethylammonium nitrate. Vaporization enthalpies are predicted within an accuracy of 20 kJ mol-1 and can be systematically interpreted on a molecular level. We present the first theoretical approach to predict proton activities in protic ionic liquids, with results fitting well into the experimentally observed correlation. Furthermore, enthalpies of vaporization were measured experimentally for some alkylammonium nitrates and an excellent linear correlation with vaporization enthalpies of their respective parent amines is observed.

Alternative aircraft fuels

NASA Technical Reports Server (NTRS)

Longwell, J. P.; Grobman, J. S.

1977-01-01

The efficient utilization of fossil fuels by future jet aircraft may necessitate the broadening of current aviation turbine fuel specifications. The most significant changes in specifications would be an increased aromatics content and a higher final boiling point in order to minimize refinery energy consumption and costs. These changes would increase the freezing point and might lower the thermal stability of the fuel, and could cause increased pollutant emissions, increased combustor liner temperatures, and poorer ignition characteristics. The effects that broadened specification fuels may have on present-day jet aircraft and engine components and the technology required to use fuels with broadened specifications are discussed.

Study on Fins' Effect of Boiling Flow in Millimeter Channel Heat Exchanger

NASA Astrophysics Data System (ADS)

Watanabe, Satoshi

2005-11-01

Recently, a lot of researches about compact heat exchangers with mini-channels have been carried out with the hope of obtaining a high-efficiency heat transfer, due to the higher ratio of surface area than existing heat exchangers. However, there are many uncertain phenomena in fields such as boiling flow in mini-channels. Thus, in order to understand the boiling flow in mini-channels to design high-efficiency heat exchangers, this work focused on the visualization measurement of boiling flow in a millimeter channel. A transparent acrylic channel (heat exchanger form), high-speed camera (2000 fps at 1024 x 1024 pixels), and halogen lamp (backup light) were used as the visualization system. The channel's depth is 2 mm, width is 30 mm, and length is 400 mm. In preparation for commercial use, two types of channels were experimented on: a fins type and a normal slit type (without fins). The fins are circular cylindrical obstacles (diameter is 5 mm) to promote heat transfer, set in a triangular array (distance between each center point is 10 mm). Especially in this work, boiling flow and heat transfer promotion in the millimeter channel heat exchanger with fins was evaluated using a high-speed camera.

An Investigation of College Chemistry Students' Understanding of Structure-Property Relationships

ERIC Educational Resources Information Center

Cooper, Melanie M.; Corley, Leah M.; Underwood, Sonia M.

2013-01-01

The connection between the molecular-level structure of a substance and its macroscopic properties is a fundamental concept in chemistry. Students in college-level general and organic chemistry courses were interviewed to investigate how they used structure-property relationships to predict properties such as melting and boiling points. Although…

49 CFR 178.338-9 - Holding time.

Code of Federal Regulations, 2014 CFR

2014-10-01

... cryogenic liquid having a boiling point, at a pressure of one atmosphere, absolute, no lower than the design... that liquid and stabilized to the lowest practical pressure, which must be equal to or less than the... combined liquid and vapor lading at the pressure offered for transportation, and the set pressure of the...

78 FR 6400 - Results of FAA Nitrous Oxide BLEVE Characterization Testing

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-30

... point. The FAA's Office of Commercial Space Transportation sponsored tests of liquid-phase nitrous oxide... storage and handling is a Boiling Liquid Expanding Vapor Explosion (BLEVE), which results from a sudden... nitrous oxide, and to demonstrate that a BLEVE would not occur if the liquid is maintained at temperatures...

THE HEAT CAPACITY OF FLUORINATED PROPANE AND BUTANE DERIVATIVES BY DIFFERENTIAL SCANNING CALORIMETRY

EPA Science Inventory

The paper gives results of the measurement (to 3% accuracy) of the constant-pressure liquid-phase heat capacities of 21 hydrogen-containing fluorinated propane and butane derivatives and one fluorinated ether (CF3OCF2H) with boiling points ranging from -34.6 to 76.7 C, using diff...

27 CFR 21.95 - Alpha terpineol.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Alpha terpineol. 21.95 Section 21.95 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Alpha terpineol. (a) Boiling point at 752mm 218.8-219.4 °C. (b) Density at 15° 0.9386. (c) Refractive...

27 CFR 21.95 - Alpha terpineol.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Alpha terpineol. 21.95 Section 21.95 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Alpha terpineol. (a) Boiling point at 752mm 218.8-219.4 °C. (b) Density at 15° 0.9386. (c) Refractive...

27 CFR 21.95 - Alpha terpineol.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Alpha terpineol. 21.95 Section 21.95 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Alpha terpineol. (a) Boiling point at 752mm 218.8-219.4 °C. (b) Density at 15° 0.9386. (c) Refractive...

27 CFR 21.95 - Alpha terpineol.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Alpha terpineol. 21.95 Section 21.95 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Alpha terpineol. (a) Boiling point at 752mm 218.8-219.4 °C. (b) Density at 15° 0.9386. (c) Refractive...

27 CFR 21.95 - Alpha terpineol.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Alpha terpineol. 21.95 Section 21.95 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Alpha terpineol. (a) Boiling point at 752mm 218.8-219.4 °C. (b) Density at 15° 0.9386. (c) Refractive...

What Do Data Mean for Pre-Service Chemistry Teachers?

ERIC Educational Resources Information Center

Gültepe, Nejla

2016-01-01

This phenomologic study was carried out in order to determine how 63 pre-service chemistry teachers graduated from Chemistry Branch of Science Faculty in the pedagogical training program during 2013-2015 academic years defined the concepts of density and melting and boiling points and how they interpreted the data in micro levels. A diagnostic…

46 CFR 38.10-5 - Filling and discharge pipes-TB/ALL.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-closing valve shall satisfy the requirements of § 38.10-1(j). (b) For pressure vessel type tanks the... the piping enters the tank. For pressure vessel type tanks operating at low pressure and with service temperature near the cargo atmospheric boiling point, the Commandant may approve individual installations...

27 CFR 21.101 - tert-Butyl alcohol.

Code of Federal Regulations, 2013 CFR

2013-04-01

... needle). Above 20 °C. (f) Identification test. Place five drops of a solution containing approximately 0... (dissolve 5 grams of red mercuric oxide in 20 ml of concentrated sulfuric acid; add this solution to 80 ml of distilled water, and filter when cool). Heat the mixture just to the boiling point and remove from...

27 CFR 21.101 - tert-Butyl alcohol.

Code of Federal Regulations, 2014 CFR

2014-04-01

... needle). Above 20 °C. (f) Identification test. Place five drops of a solution containing approximately 0... (dissolve 5 grams of red mercuric oxide in 20 ml of concentrated sulfuric acid; add this solution to 80 ml of distilled water, and filter when cool). Heat the mixture just to the boiling point and remove from...

27 CFR 21.101 - tert-Butyl alcohol.

Code of Federal Regulations, 2012 CFR

2012-04-01

... needle). Above 20 °C. (f) Identification test. Place five drops of a solution containing approximately 0... (dissolve 5 grams of red mercuric oxide in 20 ml of concentrated sulfuric acid; add this solution to 80 ml of distilled water, and filter when cool). Heat the mixture just to the boiling point and remove from...

Depletion and biodegradation of hydrocarbons in dispersions and emulsions of the Macondo 252 oil generated in an oil-on-seawater mesocosm flume basin.

PubMed

Brakstad, Odd G; Daling, Per S; Faksness, Liv-G; Almås, Inger K; Vang, Siv-H; Syslak, Line; Leirvik, Frode

2014-07-15

Physically and chemically (Corexit 9500) generated Macondo 252 oil dispersions, or emulsions (no Corexit), were prepared in an oil-on-seawater mesocosm flume basin at 30-32 °C, and studies of oil compound depletion performed for up to 15 days. The use of Corexit 9500 resulted in smaller median droplet size than in a physically generated dispersion. Rapid evaporation of low boiling point oil compounds (C⩽15) appeared in all the experiments. Biodegradation appeared to be an important depletion process for compounds with higher boiling points in the dispersions, but was negligible in the surface emulsions. While n-alkane biodegradation was faster in chemically than in physically dispersed oil no such differences were determined for 3- and 4-ring PAH compounds. In the oil dispersions prepared by Corexit 9500, increased cell concentrations, reduction in bacterial diversity, and a temporary abundance of bacteria containing an alkB gene were associated with oil biodegradation. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Characterization of pyrolysis of waste printed circuit boards by high-resolution pyrolysis gas chromatography-mass spectrometry].

PubMed

Zhang, Yanhong; Huang, Hong; Xia, Zhengbin; Chen, Huanqin

2008-07-01

Thermal degradation of pyrolysis of waste circuit boards was investigated by high-resolution pyrolysis gas chromatography-mass spectrometry (PyGC-MS) and thermogravimetry (TG). In helium atmosphere, the products of FR-4 waste printed circuit board were pyrolyzed at 350, 450, 550, 650, and 750 degrees degrees C, separately, and the pyrolysis products were identified by online MS. The results indicated that the pyrolysis products of the FR-4 waste circuit board were three kinds of substances, such as the low boiling point products, phenol, bisphenol and their related products. Moreover, under 300 degrees degrees C, only observed less pyrolysis products. As the increase of pyrolysis temperature, the relative content of the low boiling point products increased. In the range of 450-650 degrees degrees C, the qualitative analysis and character were similar, and the relative contents of phenol and bisphenol were higher. The influence of pyrolysis temperature on pyrolyzate yields was studied. On the basis of the pyrolyzate profile and the dependence of pyrolyzate yields on pyrolysis temperature, the thermal degradation mechanism of brominated epoxy resin was proposed.

Initial solubility & density evaluation of Non-Aqueous system of amino acid salts for CO2 capture: potassium prolinate blended with ethanol and ethylene glycol

NASA Astrophysics Data System (ADS)

Murshid, Ghulam; Garg, Sahil

2018-05-01

Amine scrubbing is the state of the art technology for CO2 capture, and solvent selection can significantly reduce the capital and energy cost of the process. Higher energy requirement for aqueous amine based CO2 removal process is still a most important downside preventive its industrial deployment. Therefore, in this study, novel non-aqueous based amino acid salt system consisting of potassium prolinate, ethanol and ethylene glycol has been studied. This work presents initial CO2 solubility study and important physical properties i.e. density of the studied solvent system. Previous work showed that non-aqueous system of potassium prolinate and ethanol has good absorption rates and requires lower energy for solvent regeneration. However, during regeneration, solvent loss issues were found due to lower boiling point of the ethanol. Therefore, ethylene glycol was added into current studied system for enhancing the overall boiling point of the system. The good initial CO2 solubility and low density of studied solvent system offers several advantages as compared to conventional amine solutions.

Science at Home: Measuring a Thermophysical Property of Water with a Microwave Oven

PubMed Central

Levine, Zachary H.

2018-01-01

A measurement of a thermophysical property of water is made using items found in the author’s home. Specifically, the ratio of the energy required to heat water from the melting point to boiling to the energy required to completely boil away the water is found to be 5.7. This may be compared to the standard value of 5.5. The close agreement is not representative of the actual uncertainties in this simple experiment. Heating water in a microwave oven can let a student apply the techniques of quantitative science based on questions generated by his or her scientific curiosity. PMID:29542737

Process and catalyst for converting synthesis gas to liquid hydrocarbon mixture

DOEpatents

Rao, V. Udaya S.; Gormley, Robert J.

1987-01-01

Synthesis gas containing CO and H.sub.2 is converted to a high-octane hydrocarbon liquid in the gasoline boiling point range by bringing the gas into contact with a heterogeneous catalyst including, in physical mixture, a zeolite molecular sieve, cobalt at 6-20% by weight, and thoria at 0.5-3.9% by weight. The contacting occurs at a temperature of 250.degree.-300.degree. C., and a pressure of 10-30 atmospheres. The conditions can be selected to form a major portion of the hydrocarbon product in the gasoline boiling range with a research octane of more than 80 and less than 10% by weight aromatics.

Drop Impact on Superheated Surfaces

NASA Astrophysics Data System (ADS)

Tran, Tuan; Staat, Hendrik J. J.; Prosperetti, Andrea; Sun, Chao; Lohse, Detlef

2012-01-01

At the impact of a liquid droplet on a smooth surface heated above the liquid’s boiling point, the droplet either immediately boils when it contacts the surface (“contact boiling”), or without any surface contact forms a Leidenfrost vapor layer towards the hot surface and bounces back (“gentle film boiling”), or both forms the Leidenfrost layer and ejects tiny droplets upward (“spraying film boiling”). We experimentally determine conditions under which impact behaviors in each regime can be realized. We show that the dimensionless maximum spreading γ of impacting droplets on the heated surfaces in both gentle and spraying film boiling regimes shows a universal scaling with the Weber number We (γ˜We2/5), which is much steeper than for the impact on nonheated (hydrophilic or hydrophobic) surfaces (γ˜We1/4). We also interferometrically measure the vapor thickness under the droplet.

Unorthodox bubbles when boiling in cold water.

PubMed

Parker, Scott; Granick, Steve

2014-01-01

High-speed movies are taken when bubbles grow at gold surfaces heated spotwise with a near-infrared laser beam heating water below the boiling point (60-70 °C) with heating powers spanning the range from very low to so high that water fails to rewet the surface after bubbles detach. Roughly half the bubbles are conventional: They grow symmetrically through evaporation until buoyancy lifts them away. Others have unorthodox shapes and appear to contribute disproportionately to heat transfer efficiency: mushroom cloud shapes, violently explosive bubbles, and cavitation events, probably stimulated by a combination of superheating, convection, turbulence, and surface dewetting during the initial bubble growth. Moreover, bubbles often follow one another in complex sequences, often beginning with an unorthodox bubble that stirs the water, followed by several conventional bubbles. This large dataset is analyzed and discussed with emphasis on how explosive phenomena such as cavitation induce discrepancies from classical expectations about boiling.

Distillation Apparatuses Using Household Items

NASA Astrophysics Data System (ADS)

Campanizzi, Danielle R. D.; Mason, Brenda; Hermann, Christine K. F.

1999-08-01

A simple apparatus to demonstrate distillation principles can be very difficult to build without the specialty glassware found in chemistry laboratories. We have built inexpensive but effective distillation apparatuses from equipment that can be easily purchased at local department, grocery, or hardware stores. In one apparatus, colored water is heated to boiling and the condensed vapors drip into another container. In another apparatus, acetone is heated to boiling with hot water and the acetone vapors condense onto a Styrofoam cup. The Styrofoam cup is softened by the acetone and collapses. Rubbing alcohol can be used instead of acetone, but the cup is not softened and the boiling point is much higher. Both apparatuses can be used in a classroom. Both are simple, cost-effective ways of demonstrating distillation, evaporation, and condensation. They would be ideal to use in elementary and middle school classrooms when explaining these concepts.

Assessing the microbiological performance and potential cost of boiling drinking water in urban Zambia.

PubMed

Psutka, Rebecca; Peletz, Rachel; Michelo, Sandford; Kelly, Paul; Clasen, Thomas

2011-07-15

Boiling is the most common method of disinfecting water in the home and the benchmark against which other point-of-use water treatment is measured. In a six-week study in peri-urban Zambia, we assessed the microbiological effectiveness and potential cost of boiling among 49 households without a water connection who reported "always" or "almost always" boiling their water before drinking it. Source and household drinking water samples were compared weekly for thermotolerant coliforms (TTC), an indicator of fecal contamination. Demographics, costs, and other information were collected through surveys and structured observations. Drinking water samples taken at the household (geometric mean 7.2 TTC/100 mL, 95% CI, 5.4-9.7) were actually worse in microbiological quality than source water (geometric mean 4.0 TTC/100 mL, 95% CI, 3.1-5.1) (p < 0.001), although both are relatively low levels of contamination. Only 60% of drinking water samples were reported to have actually been boiled at the time of collection from the home, suggesting over-reporting and inconsistent compliance. However, these samples were of no higher microbiological quality. Evidence suggests that water quality deteriorated after boiling due to lack of residual protection and unsafe storage and handling. The potential cost of fuel or electricity for boiling was estimated at 5% and 7% of income, respectively. In this setting where microbiological water quality was relatively good at the source, safe-storage practices that minimize recontamination may be more effective in managing the risk of disease from drinking water at a fraction of the cost of boiling.

A non-ideal model for predicting the effect of dissolved salt on the flash point of solvent mixtures.

PubMed

Liaw, Horng-Jang; Wang, Tzu-Ai

2007-03-06

Flash point is one of the major quantities used to characterize the fire and explosion hazard of liquids. Herein, a liquid with dissolved salt is presented in a salt-distillation process for separating close-boiling or azeotropic systems. The addition of salts to a liquid may reduce fire and explosion hazard. In this study, we have modified a previously proposed model for predicting the flash point of miscible mixtures to extend its application to solvent/salt mixtures. This modified model was verified by comparison with the experimental data for organic solvent/salt and aqueous-organic solvent/salt mixtures to confirm its efficacy in terms of prediction of the flash points of these mixtures. The experimental results confirm marked increases in liquid flash point increment with addition of inorganic salts relative to supplementation with equivalent quantities of water. Based on this evidence, it appears reasonable to suggest potential application for the model in assessment of the fire and explosion hazard for solvent/salt mixtures and, further, that addition of inorganic salts may prove useful for hazard reduction in flammable liquids.

Boiling of an emulsion in a yield stress fluid.

PubMed

Guéna, Geoffroy; Wang, Ji; d'Espinose, Jean-Baptiste; Lequeux, François; Talini, Laurence

2010-11-01

We report the boiling behavior of pentane emulsified in a yield stress fluid, a colloidal clay (Laponite) suspension. We have observed that a superheated state is easily reached: the emulsion, heated more than 50 °C above the alkane boiling point, does not boil. Superheating is made possible by the suppression of heterogeneous nucleation in pentane, resulting from the emulsification process, a phenomenon evidenced decades ago in studies of the superheating of two phase fluids. We have furthermore studied the growth of isolated bubbles nucleated in the emulsion. The rate of increase of the bubble radius with time depends on both the temperature and emulsion volume fraction but, rather unexpectedly, does not depend on the fluid rheology. We show that the bubbles grow by diffusion of the alkane through the aqueous phase between liquid droplets and bubbles, analogously to an Ostwald ripening process. The peculiarity of the process reported here is that a layer depleted in oil droplets forms around the bubble, layer to which the alkane concentration gradient is confined. We successfully describe our experimental results with a simple transfer model.

Stability of film boiling on inclined plates and spheres

NASA Astrophysics Data System (ADS)

Aursand, Eskil; Hammer, Morten; Munkejord, Svend Tollak; Müller, Bernhard; Ytrehus, Tor

2017-11-01

In film boiling, a continuous sub-millimeter vapor film forms between a liquid and a heated surface, insulating the two from each other. While quite accurate steady state solutions are readily obtained, the intermediate Reynolds numbers can make transient analysis challenging. The present work is a theoretical study of film boiling instabilities. We study the formation of travelling waves that are a combination of Kelvin-Helmholtz and the Rayleigh-Taylor instabilities. In particular, we study how the nature of this process depends on the Reynolds number, the Bond number, and the inclination of the submerged heated plate. In addition we extend the analysis to the case of a submerged heated sphere. Modelling of the transient dynamics of such films is important for answering practical questions such as how instabilities affect the overall heat transfer, and whether they can lead to complete film boiling collapse (Leidenfrost point). This work has been financed under the MAROFF program. We acknowledge the Research Council of Norway (244076/O80) and The Gas Technology Centre NTNU-SINTEF (GTS) for support.

DETERMINATION OF CONVECTIVE HEAT TRANSFER COEFFICIENT AT THE OUTER SURFACE OF A CRYOVIAL BEING PLUNGED INTO LIQUID NITROGEN.

PubMed

Wang, T; Zhao, G; Tang, H Y; Jiang, Z D

2015-01-01

Cell survival upon cryopreservation is affected by the cooling rate. However, it is difficult to model the heat transfer process or to predict the cooling curve of a cryoprotective agent (CPA) solution due to the uncertainty of its convective heat transfer coefficient (h). To measure the h and to better understand the heat transfer process of cryovials filled with CPA solution being plunged in liquid nitrogen. The temperatures at three locations of the CPA solution in a cryovial were measured. Different h values were selected after the cooling process was modeled as natural convection heat transfer, the film boiling and the nucleate boiling, respectively. And the temperatures of the selected points are simulated based on the selected h values. h was determined when the simulated temperature best fitted the experimental temperature. When the experimental results were best fitted, according to natural convection heat transfer model, h(1) = 120 W/(m(2)·K) while due to film boiling and nucleate boiling regimes h(f) = 5 W/(m(2)·K) followed by h(n) = 245 W/(m(2)·K). These values were verified by the differential cooling rates at the three locations of a cryovial. The heat transfer process during cooling in liquid nitrogen is better modeled as film boiling followed by nucleate boiling.

77 FR 15609 - Revocation of TSCA Section 4 Testing Requirements for Certain High Production Volume Chemical...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-16

..., processing, use, or disposal of those chemical substances on health or the environment can reasonably be... boiling point listed for that chemical substance in the ``Handbook of Chemistry and Physics'' (Ref. 21...-0182). 21. CRC Handbook of Chemistry and Physics. 85th Edition. David R. Lide, ed., CRC Press. Boca...

Prediction of Environmental Impact of High-Energy Materials with Atomistic Computer Simulations

DTIC Science & Technology

2010-11-01

from a training set of compounds. Other methods include Quantitative Struc- ture-Activity Relationship ( QSAR ) and Quantitative Structure-Property...26 28 the development of QSPR/ QSAR models, in contrast to boiling points and critical parameters derived from empirical correlations, to improve...Quadratic Configuration Interaction Singles Doubles QSAR Quantitative Structure-Activity Relationship QSPR Quantitative Structure-Property

Chemical Characterization of Simulated Boiling Water Reactor Coolant

DTIC Science & Technology

1990-05-01

33 Table 3. 1: BCCL Sample Block Design Calculations ........................................... 45 Table 5.1: Gas Absorption...cover gas . The cool, degassed pure water is pumped through a regenerative heat exchanger and then through an electric feedwater heater. The feedwater is...POINTS DWCMRHEAT DOWNOMER---EXCHANGER CHEMICAL GAHP INJECTIOIN PUMP SYSTEM COIVER GAS IN-CLIRE SECTION CAGN TANK RECOMBINER! ______ DEMINERALIZER (Cic

NREL's CelA Catalyzes Plant Cell Walls Faster | News | NREL

Science.gov Websites

12, 2015 Close-up photo of a scientist in safety glasses examining small items in plastic containers because high temperatures mean faster action. Also, because it can operate above the boiling point of alcohol, the alcohol is separated naturally, saving a costly step in the conversion process-and the high

A Research Study to Investigate PCBs in School Buildings: Final Research Plan. EPA 600/R-10/074

ERIC Educational Resources Information Center

US Environmental Protection Agency, 2010

2010-01-01

Polychlorinated biphenyls (PCBs) are synthetic chemicals that were manufactured in the United States between about 1930 and 1977 for use in various industrial and commercial applications because of their nonflammability, chemical stability, high boiling point, and electrical insulation properties (ATSDR, 2000). PCBs were used in numerous products…

Our Educational Melting Pot: Have We Reached the Boiling Point?

ERIC Educational Resources Information Center

Lauderdale, Katherine Lynn, Ed.; Bonilla, Carlos A., Ed.

The articles and excerpts in this collection illustrate the complexity of the melting pot concept. Multiculturalism has become a watchword in American life and education, but it may be that in trying to atone for past transgressions educators and others are simply going too far. These essays illustrate some of the problems of a multicultural…

Fractional Distillation of Air and Other Demonstrations with Condensed Gases

ERIC Educational Resources Information Center

Oliver-Hoyo, Maria; Switzer, William L., III; Eierman, Robert

2005-01-01

The learning objectives of the fractional distillation of air and other demonstrations includes observing N2, O2, CO2 and H2O in air, studying the fractional separation of components based on boiling point differences and so on. The materials, reagent and equipment preparation, experimental procedures, hazards of the demonstration are also…

Correction of wheat meal falling number to a common barometric pressure at simulated laboratory elevations of 0 to 1500 meters

USDA-ARS?s Scientific Manuscript database

Falling number, a procedure that indirectly gauges germination enzyme activity in wheat by its measurement of the viscous behavior of a heated starch-water mixture, is affected by the immersion water bath temperature. Maintained at boiling point, the water bath temperature is determined by barometr...

46 CFR 154.903 - Inert gas systems: General.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Atmospheric Control in Cargo Containment Systems § 154.903 Inert gas systems: General. (a) Inert gas carried... tanks, hold and interbarrier spaces, and insulation. (b) The boiling point and dewpoint at atmospheric pressure of the inert gas must be below the temperature of any surface in those spaces or −45 °C (−49 °F...

New Fantasy Football League Tests NCAA's Rules on Amateur Status

ERIC Educational Resources Information Center

Moser, Kate

2008-01-01

The long-simmering debate over the commercialization of college sports reached a boiling point recently when CBS, the NCAA's key corporate partner, announced that it was creating a fantasy football league that uses college athletes' names. Not everyone however, is quite so enthusiastic. Some observers see it as part of a continuing assault on the…

SEM technique for displaying the three-dimensional structure of wood

Treesearch

C.W. McMillin

1977-01-01

Samples of green Liriodendron tulipifera L. were bandsawed into l/4-inch cubes and boiled in water for 1 hour. Smooth intersecting radial, tangential, and transverse surfaces were prepared with a handheld, single-edge razor blade. After drying, the cubes were affixed to stubs so that the intersection point of the three sectioned surfaces was...

SEM technique for displaying the three-dimensional structure of wood

Treesearch

Charles W. McMillin

1977-01-01

Samples of green Liriodendron tulipifera L. were bandsawed into 1/4-inch cubes and boiled in water for 1 hour. Smooth intersecting radial, tangential, and transverse surfaces were prepared with a handheld, single-edge razor blade. After drying, the cubes were affixed to stubs so that the intersection point of the three sectioned surfaces was...

Helping Students Assess the Relative Importance of Different Intermolecular Interactions

ERIC Educational Resources Information Center

Jasien, Paul G.

2008-01-01

A semi-quantitative model has been developed to estimate the relative effects of dispersion, dipole-dipole interactions, and H-bonding on the normal boiling points ("T[subscript b]") for a subset of simple organic systems. The model is based upon a statistical analysis using multiple linear regression on a series of straight-chain organic…

[Study of Determination of Oil Mixture Components Content Based on Quasi-Monte Carlo Method].

PubMed

Wang, Yu-tian; Xu, Jing; Liu, Xiao-fei; Chen, Meng-han; Wang, Shi-tao

2015-05-01

Gasoline, kerosene, diesel is processed by crude oil with different distillation range. The boiling range of gasoline is 35 ~205 °C. The boiling range of kerosene is 140~250 °C. And the boiling range of diesel is 180~370 °C. At the same time, the carbon chain length of differentmineral oil is different. The carbon chain-length of gasoline is within the scope of C7 to C11. The carbon chain length of kerosene is within the scope of C12 to C15. And the carbon chain length of diesel is within the scope of C15 to C18. The recognition and quantitative measurement of three kinds of mineral oil is based on different fluorescence spectrum formed in their different carbon number distribution characteristics. Mineral oil pollution occurs frequently, so monitoring mineral oil content in the ocean is very important. A new method of components content determination of spectra overlapping mineral oil mixture is proposed, with calculation of characteristic peak power integrationof three-dimensional fluorescence spectrum by using Quasi-Monte Carlo Method, combined with optimal algorithm solving optimum number of characteristic peak and range of integral region, solving nonlinear equations by using BFGS(a rank to two update method named after its inventor surname first letter, Boyden, Fletcher, Goldfarb and Shanno) method. Peak power accumulation of determined points in selected area is sensitive to small changes of fluorescence spectral line, so the measurement of small changes of component content is sensitive. At the same time, compared with the single point measurement, measurement sensitivity is improved by the decrease influence of random error due to the selection of points. Three-dimensional fluorescence spectra and fluorescence contour spectra of single mineral oil and the mixture are measured by taking kerosene, diesel and gasoline as research objects, with a single mineral oil regarded whole, not considered each mineral oil components. Six characteristic peaks are selected for characteristic peak power integration to determine components content of mineral oil mixture of gasoline, kerosene and diesel by optimal algorithm. Compared with single point measurement of peak method and mean method, measurement sensitivity is improved about 50 times. The implementation of high precision measurement of mixture components content of gasoline, kerosene and diesel provides a practical algorithm for components content direct determination of spectra overlapping mixture without chemical separation.

High freezing point fuels used for aviation turbine engines

NASA Technical Reports Server (NTRS)

Friedman, R.

1979-01-01

Broadened-specification aviation fuels could be produced from a greater fraction of crude source material with improvements in fuel supply and price. These fuels, particularly those with increased final boiling temperatures, would have higher freezing temperatures than current aviation turbine fuels. For the small but significant fraction of commercial flights where low fuel temperatures make higher freezing-point fuel use unacceptable, adaptations to the fuel or fuel system may be made to accommodate this fuel. Several techniques are discussed. Fuel heating is the most promising concept. One simple design uses existing heat rejection from the fuel-lubricating oil cooler, another uses an engine-driven generator for electrical heating.

Alternative aviation turbine fuels

NASA Technical Reports Server (NTRS)

Grobman, J.

1977-01-01

The efficient utilization of fossil fuels by future jet aircraft may necessitate the broadening of current aviation turbine fuel specifications. The most significant changes in specifications would be an increased aromatics content and a higher final boiling point in order to minimize refinery energy consumption and costs. These changes would increase the freezing point and might lower the thermal stability of the fuel and could cause increased pollutant emissions, increased smoke and carbon formation, increased combustor liner temperatures, and poorer ignition characteristics. This paper discusses the effects that broadened specification fuels may have on present-day jet aircraft and engine components and the technology required to use fuels with broadened specifications.

The use of linear expressions of solute boiling point versus retention to indicate special interactions with the molecular rings of modified cyclodextrin phases in gas chromatography

PubMed

Betts

2000-08-01

The boiling points (degrees C, 1 x 10) of diverse C10 polar solutes from volatile oils are set against their relative retention times versus n-undecane to calculate linear equations for 12 commercial modified cyclodextrin (CD) capillary phases. Ten data points are considered for each CD, then solutes are rejected until 5 or more remain that give an expression with a correlation coefficient of at least 0.990 and a standard deviation of less than 5.5. Three phases give almost perfect correlation, and 3 other CDs have difficulty complying. Solutes involved in the equations (most frequently cuminal, linalol, and carvone) are presumed to have a 'standard' polar transient interaction with the molecular rings of the CDs concerned. Several remaining solutes (mostly citral, fenchone, and menthol) exhibit extra retention over the calculated standard (up to 772%), which is believed to indicate a firm 'host' CD or 'guest' solute molecular fit in some cases. Other solutes show less retention than calculated (mostly citronellal, citronellol, estragole, and pulegone). This suggests rejection by the CD, which behaves merely as a conventional stationary phase to them. The intercept constant in the equation for each phase is suggested to be a numerical relative polarity indicator. These b values indicate that 3 hydroxypropyl CDs show the most polarity with values from 28 to 43; and CDs that are fully substituted with inert groups fall in the range of 15 to 20.

CADASTER QSPR Models for Predictions of Melting and Boiling Points of Perfluorinated Chemicals.

PubMed

Bhhatarai, Barun; Teetz, Wolfram; Liu, Tao; Öberg, Tomas; Jeliazkova, Nina; Kochev, Nikolay; Pukalov, Ognyan; Tetko, Igor V; Kovarich, Simona; Papa, Ester; Gramatica, Paola

2011-03-14

Quantitative structure property relationship (QSPR) studies on per- and polyfluorinated chemicals (PFCs) on melting point (MP) and boiling point (BP) are presented. The training and prediction chemicals used for developing and validating the models were selected from Syracuse PhysProp database and literatures. The available experimental data sets were split in two different ways: a) random selection on response value, and b) structural similarity verified by self-organizing-map (SOM), in order to propose reliable predictive models, developed only on the training sets and externally verified on the prediction sets. Individual linear and non-linear approaches based models developed by different CADASTER partners on 0D-2D Dragon descriptors, E-state descriptors and fragment based descriptors as well as consensus model and their predictions are presented. In addition, the predictive performance of the developed models was verified on a blind external validation set (EV-set) prepared using PERFORCE database on 15 MP and 25 BP data respectively. This database contains only long chain perfluoro-alkylated chemicals, particularly monitored by regulatory agencies like US-EPA and EU-REACH. QSPR models with internal and external validation on two different external prediction/validation sets and study of applicability-domain highlighting the robustness and high accuracy of the models are discussed. Finally, MPs for additional 303 PFCs and BPs for 271 PFCs were predicted for which experimental measurements are unknown. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A universal reduced glass transition temperature for liquids

NASA Technical Reports Server (NTRS)

Fedors, R. F.

1979-01-01

Data on the dependence of the glass transition temperature on the molecular structure for low-molecular-weight liquids are analyzed in order to determine whether Boyer's reduced glass transition temperature (1952) is a universal constant as proposed. It is shown that the Boyer ratio varies widely depending on the chemical nature of the molecule. It is pointed out that a characteristic temperature ratio, defined by the ratio of the sum of the melting temperature and the boiling temperature to the sum of the glass transition temperature and the boiling temperature, is a universal constant independent of the molecular structure of the liquid. The average value of the ratio obtained from data for 65 liquids is 1.15.

Science at Home: Measuring a Thermophysical Property of Water with a Microwave Oven

NASA Astrophysics Data System (ADS)

Levine, Zachary H.

2018-02-01

An attempt to calibrate a conventional oven led to making a measurement of a thermophysical property of water using items found in the author's home. Specifically, the ratio of the energy required to heat water from the melting point to boiling to the energy required to completely boil away the water is found to be 5.7. This may be compared to the standard value of 5.5. The close agreement is not representative of the actual uncertainties in this simple experiment (Fig. 1). Heating water in a microwave oven can let a student apply the techniques of quantitative science based on questions generated by his or her scientific curiosity.

Biofuel by isomerizing metathesis of rapeseed oil esters with (bio)ethylene for use in contemporary diesel engines

PubMed Central

Pfister, Kai F.; Baader, Sabrina; Baader, Mathias; Berndt, Silvia; Goossen, Lukas J.

2017-01-01

Rapeseed oil methyl ester (RME) and (bio)ethylene are converted into biofuel with an evenly rising boiling point curve, which fulfills the strict boiling specifications prescribed by the fuel standard EN 590 for modern (petro)diesel engines. Catalyzed by a Pd/Ru system, RME undergoes isomerizing metathesis in a stream of ethylene gas, leading to a defined olefin, monoester, and diester blend. This innovative refining concept requires negligible energy input (60°C) and no solvents and does not produce waste. It demonstrates that the pressing challenge of increasing the fraction of renewables in engine fuel may be addressed purely chemically rather than by motor engineering. PMID:28630908

Biofuel by isomerizing metathesis of rapeseed oil esters with (bio)ethylene for use in contemporary diesel engines.

PubMed

Pfister, Kai F; Baader, Sabrina; Baader, Mathias; Berndt, Silvia; Goossen, Lukas J

2017-06-01

Rapeseed oil methyl ester (RME) and (bio)ethylene are converted into biofuel with an evenly rising boiling point curve, which fulfills the strict boiling specifications prescribed by the fuel standard EN 590 for modern (petro)diesel engines. Catalyzed by a Pd/Ru system, RME undergoes isomerizing metathesis in a stream of ethylene gas, leading to a defined olefin, monoester, and diester blend. This innovative refining concept requires negligible energy input (60°C) and no solvents and does not produce waste. It demonstrates that the pressing challenge of increasing the fraction of renewables in engine fuel may be addressed purely chemically rather than by motor engineering.

Evaluation of different cooking conditions on broccoli (Brassica oleracea var. italica) to improve the nutritional value and consumer acceptance.

PubMed

Bongoni, Radhika; Verkerk, Ruud; Steenbekkers, Bea; Dekker, Matthijs; Stieger, Markus

2014-09-01

The objective of this study was to gain insights into the effect of the cooking method on the liking as well as the retention of glucosinolates in broccoli. With this knowledge it can be concluded whether the health aspects of broccoli be improved by the cooking method without deteriorating sensory perception. For this, broccoli was cooked by methods commonly applied by consumers: boiling with a cold (water) start; boiling with a hot (water) start; and steaming. Firmness, greenness and amount of total glucosinolates in cooked broccoli were instrumentally determined. Sensory evaluation by untrained consumers (n = 99) for liking and sensory attributes intensity rating were performed on broccoli cooked by steaming and boiling-cold start at three time points, which resulted in 'high', 'medium', 'low' firm broccoli samples. At the end of cooking, steaming showed an increase in the amount of total glucosinolates (+17%). Boiling-hot start (-41%) and boiling-cold start (-50%) showed a decrease in amount of total glucosinolates. Sensory evaluation did not show statistically significant differences between steaming and boiling-cold start in liking at 'high' and 'medium' firmness; and in the attribute intensity ratings (except for juiciness at 'medium' firmness, and flavour at 'medium' and 'low' firmness). This study demonstrates that medium firm broccoli showed optimum liking and that steaming compared to boiled-cold start showed higher amount of glucosinolates. It is concluded that the health aspects of broccoli can be improved without reducing the sensory aspects by optimising the cooking method.

Changes in the Microbial Composition of Microbrewed Beer during the Process in the Actual Manufacturing Line.

PubMed

Kim, S A; Jeon, S H; Kim, N H; Kim, H W; Lee, N Y; Cho, T J; Jung, Y M; Lee, S H; Hwang, I G; Rhee, M S

2015-12-01

This study investigated changes in the microbial composition of microbrewed beer during the manufacturing processes and identified potential microbial hazards, effective critical quality control points, and potential contamination routes. Comprehensive quantitative (aerobic plate count, lactic acid bacteria, fungi, acetic acid bacteria, coliforms, and Bacillus cereus) and qualitative (Escherichia coli and eight foodborne pathogens) microbiological analyses were performed using samples of raw materials (malt and manufacturing water), semiprocessed products (saccharified wort, boiled wort, and samples taken during the fermentation and maturation process), and the final product obtained from three plants. The initial aerobic plate count and lactic acid bacteria counts in malt were 5.2 and 4.3 log CFU/g, respectively. These counts were reduced to undetectable levels by boiling but were present at 2.9 and 0.9 log CFU/ml in the final product. Fungi were initially present at 3.6 log CFU/g, although again, the microbes were eliminated by boiling; however, the level in the final product was 4.6 log CFU/ml. No E. coli or foodborne pathogens (except B. cereus) were detected. B. cereus was detected at all stages, although it was not present in the water or boiled wort (total detection rate ¼ 16.4%). Results suggest that boiling of the wort is an effective microbial control measure, but careful management of raw materials and implementation of effective control measures after boiling are needed to prevent contamination of the product after the boiling step. The results of this study may constitute useful and comprehensive information regarding the microbiological quality of microbrewed beer.

Response of two-phase droplets to intense electromagnetic radiation

NASA Technical Reports Server (NTRS)

Spann, James F.; Maloney, Daniel J.; Lawson, William F.; Casleton, Kent H.

1993-01-01

The behavior of two-phase droplets subjected to high intensity radiation pulses is studied. Droplets are highly absorbing solids in weakly absorbing liquid medium. The objective of the study was to define heating thresholds required for causing explosive boiling and secondary atomization of the fuel droplet. The results point to mechanisms for energy storage and transport in two-phase systems.

Calculating the Entropy of Solid and Liquid Metals, Based on Acoustic Data

NASA Astrophysics Data System (ADS)

Tekuchev, V. V.; Kalinkin, D. P.; Ivanova, I. V.

2018-05-01

The entropies of iron, cobalt, rhodium, and platinum are studied for the first time, based on acoustic data and using the Debye theory and rigid-sphere model, from 298 K up to the boiling point. A formula for the melting entropy of metals is validated. Good agreement between the research results and the literature data is obtained.

Vapor Pressure Data and Analysis for Selected Organophosphorus Compounds: DIBMP, DCMP, IMMP, IMPA, EMPA, and MPFA

DTIC Science & Technology

2017-04-01

Methodology, Statistics, and Applications; CRDEC-TR-386; U.S. Army Chemical Research, Development and Engineering Center: Aberdeen Proving Ground...Approved for public release; distribution unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT: Recent work from our laboratory has focused on chemical ...vaporization Volatility Differential scanning calorimetry (DSC) Vapor saturation Boiling point Diisobutyl methylphosphonate (DIBMP), Chemical Abstracts

Demonstration Show That Promotes and Assesses Conceptual Understanding Using the Structure of Drama

ERIC Educational Resources Information Center

Walter Kerby, Holly; DeKorver, Brittland K.; Cantor, Joanne; Weiland, Marcia J.; Babiarz, Christopher L.

2016-01-01

Demonstration shows are a widely used form of Informal Science Education. While there is evidence that the shows are highly enjoyable, little work has been done to investigate the cognitive impacts of these shows. This article describes the development and production of "The Boiling Point," a show that uses the structure of a play to…

Use of Concept Profile Analysis to Identify Difficulties in Solving Science Problems.

ERIC Educational Resources Information Center

Gorodetsky, Malka; Hoz, Ron

1980-01-01

Proposed is a new method for analyzing how concepts are used in the process of problem solving in science. Through the use of a "thinking aloud" interview technique, 21 tenth-grade students worked with a problem concerning the boiling point of water at the Dead Sea. Interview protocols were analyzed to develop students' concept profiles.…

Liquid-vapor phase equilibria of three-component systems of propanol-2-propanoic acid esters

NASA Astrophysics Data System (ADS)

Suntsov, Yu. K.; Goryunov, V. A.; Chuikov, A. M.

2017-12-01

The boiling points of solutions of three-component systems formed by propanol-2 and propanoic acid esters are measured at different pressures by means of ebulliometry. The coefficients of the activity of the solutions' components are measured using Wilson and nonrandom two-liquid (NRTL) equations. The results from calculations are in line with the experimental data.

APPARATUS FOR CONTROL OF A BOILING REACTOR RESPONSIVE TO STEAM DEMAND

DOEpatents

Treshow, M.

1963-07-23

A method of controlling a fuel-rod-in-tube-type boilingwater reactor having nozzles at the point of water entry into the tube is described. Water is pumped into the nozzles by an auxiliary pump operated by steam from an interstage position of the associated turbine, so that the pumping speed is responsive to turbine demand. (AEC)

Cyanide toxicity from the thermal degradation of rigid polyurethane foam.

PubMed

Bell, R H; Stemmer, K L; Barkley, W; Hollingsworth, L D

1979-09-01

Thermal degradation products (tdp) from a model, rigid polyurethane foam were collected in such a manner as to eliminate carbon monoxide and other gases with low boiling points. The effects in rats resulting from intratracheal intubation (I.T.) of the tdp are discussed. Cyanide was found to be a major factor associated with severe toxic responses of the experimental rats.

78 FR 27860 - Revocation of TSCA Section 4 Testing Requirements for One High Production Volume Chemical Substance

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-13

... for C.I. Pigment Blue 61 (Ref. 8). As a result, a biodegradation study of C.I. Pigment Blue 56, found adequate by an EPA review, satisfies the need for biodegradation data on C.I. Pigment Blue 61 (Ref. 8..., boiling point, vapor pressure, water solubility, biodegradation, fish acute toxicity, mammalian acute...

Optical Sensor for Diverse Organic Vapors at ppm Concentration Ranges

PubMed Central

Thomas, J. Christopher; Trend, John E.; Rakow, Neal A.; Wendland, Michael S.; Poirier, Richard J.; Paolucci, Dora M.

2011-01-01

A broadly responsive optical organic vapor sensor is described that responds to low concentrations of organic vapors without significant interference from water vapor. Responses to several classes of organic vapors are highlighted, and trends within classes are presented. The relationship between molecular properties (vapor pressure, boiling point, polarizability, and refractive index) and sensor response are discussed. PMID:22163798

Solvent effects on polymer sorting of carbon nanotubes with applications in printed electronics.

PubMed

Wang, Huiliang; Hsieh, Bing; Jiménez-Osés, Gonzalo; Liu, Peng; Tassone, Christopher J; Diao, Ying; Lei, Ting; Houk, Kendall N; Bao, Zhenan

2015-01-07

Regioregular poly(3-alkylthiophene) (P3AT) polymers have been previously reported for the selective, high-yield dispersion of semiconducting single-walled carbon nanotubes (SWCNTs) in toluene. Here, five alternative solvents are investigated, namely, tetrahydrofuran, decalin, tetralin, m-xylene, and o-xylene, for the dispersion of SWCNTs by poly(3-dodecylthiophene) P3DDT. The dispersion yield could be increased to over 40% using decalin or o-xylene as the solvents while maintaining high selectivity towards semiconducting SWCNTs. Molecular dynamics (MD) simulations in explicit solvents are used to explain the improved sorting yield. In addition, a general mechanism is proposed to explain the selective dispersion of semiconducting SWCNTs by conjugated polymers. The possibility to perform selective sorting of semiconducting SWCNTs using various solvents provides a greater diversity of semiconducting SWCNT ink properties, such as boiling point, viscosity, and surface tension as well as toxicity. The efficacy of these new semiconducting SWCNT inks is demonstrated by using the high boiling point and high viscosity solvent tetralin for inkjet-printed transistors, where solvent properties are more compatible with the inkjet printing head and improved droplet formation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An evaluation of the sonoporation potential of low-boiling point phase-change ultrasound contrast agents in vitro.

PubMed

Fix, Samantha M; Novell, Anthony; Yun, Yeoheung; Dayton, Paul A; Arena, Christopher B

2017-01-01

Phase-change ultrasound contrast agents (PCCAs) offer a solution to the inherent limitations associated with using microbubbles for sonoporation; they are characterized by prolonged circulation lifetimes, and their nanometer-scale sizes may allow for passive accumulation in solid tumors. As a first step towards the goal of extravascular cell permeabilization, we aim to characterize the sonoporation potential of a low-boiling point formulation of PCCAs in vitro. Parameters to induce acoustic droplet vaporization and subsequent microbubble cavitation were optimized in vitro using high-speed optical microscopy. Sonoporation of pancreatic cancer cells in suspension was then characterized at a range of pressures (125-600 kPa) and pulse lengths (5-50 cycles) using propidium iodide as an indicator molecule. We achieved sonoporation efficiencies ranging from 8 ± 1% to 36 ± 4% (percent of viable cells), as evidenced by flow cytometry. Increasing sonoporation efficiency trended with increasing pulse length and peak negative pressure. We conclude that PCCAs can be used to induce the sonoporation of cells in vitro, and our results warrant further investigation into the use of PCCAs as extravascular sonoporation agents in vivo.

Contrast-enhanced ultrasound imaging and in vivo circulatory kinetics with low-boiling-point nanoscale phase-change perfluorocarbon agents.

PubMed

Sheeran, Paul S; Rojas, Juan D; Puett, Connor; Hjelmquist, Jordan; Arena, Christopher B; Dayton, Paul A

2015-03-01

Many studies have explored phase-change contrast agents (PCCAs) that can be vaporized by an ultrasonic pulse to form microbubbles for ultrasound imaging and therapy. However, few investigations have been published on the utility and characteristics of PCCAs as contrast agents in vivo. In this study, we examine the properties of low-boiling-point nanoscale PCCAs evaluated in vivo and compare data with those for conventional microbubbles with respect to contrast generation and circulation properties. To do this, we develop a custom pulse sequence to vaporize and image PCCAs using the Verasonics research platform and a clinical array transducer. Results indicate that droplets can produce contrast enhancement similar to that of microbubbles (7.29 to 18.24 dB over baseline, depending on formulation) and can be designed to circulate for as much as 3.3 times longer than microbubbles. This study also reports for the first time the ability to capture contrast washout kinetics of the target organ as a measure of vascular perfusion. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Implementation of hazard analysis and critical control point (HACCP) in dried anchovy production process

NASA Astrophysics Data System (ADS)

Citraresmi, A. D. P.; Wahyuni, E. E.

2018-03-01

The aim of this study was to inspect the implementation of Hazard Analysis and Critical Control Point (HACCP) for identification and prevention of potential hazards in the production process of dried anchovy at PT. Kelola Mina Laut (KML), Lobuk unit, Sumenep. Cold storage process is needed in each anchovy processing step in order to maintain its physical and chemical condition. In addition, the implementation of quality assurance system should be undertaken to maintain product quality. The research was conducted using a survey method, by following the whole process of making anchovy from the receiving raw materials to the packaging of final product. The method of data analysis used was descriptive analysis method. Implementation of HACCP at PT. KML, Lobuk unit, Sumenep was conducted by applying Pre Requisite Programs (PRP) and preparation stage consisting of 5 initial stages and 7 principles of HACCP. The results showed that CCP was found in boiling process flow with significant hazard of Listeria monocytogenesis bacteria and final sorting process with significant hazard of foreign material contamination in the product. Actions taken were controlling boiling temperature of 100 – 105°C for 3 - 5 minutes and training for sorting process employees.

Best estimate plus uncertainty analysis of departure from nucleate boiling limiting case with CASL core simulator VERA-CS in response to PWR main steam line break event

DOE PAGES

Brown, Cameron S.; Zhang, Hongbin; Kucukboyaci, Vefa; ...

2016-09-07

VERA-CS (Virtual Environment for Reactor Applications, Core Simulator) is a coupled neutron transport and thermal-hydraulics subchannel code under development by the Consortium for Advanced Simulation of Light Water Reactors (CASL). VERA-CS was used to simulate a typical pressurized water reactor (PWR) full core response with 17x17 fuel assemblies for a main steam line break (MSLB) accident scenario with the most reactive rod cluster control assembly stuck out of the core. The accident scenario was initiated at the hot zero power (HZP) at the end of the first fuel cycle with return to power state points that were determined by amore » system analysis code and the most limiting state point was chosen for core analysis. The best estimate plus uncertainty (BEPU) analysis method was applied using Wilks’ nonparametric statistical approach. In this way, 59 full core simulations were performed to provide the minimum departure from nucleate boiling ratio (MDNBR) at the 95/95 (95% probability with 95% confidence level) tolerance limit. The results show that this typical PWR core remains within MDNBR safety limits for the MSLB accident.« less

[Electrocoagulation on a fragment of anterior abdominal rectal muscle for the control of presacral bleeding during rectal resection].

PubMed

Casal Núñez, José Enrique; Martínez, María Teresa García; Poblador, Alejandro Ruano

2012-03-01

Presacral venous haemorrhage during rectal movement is low, but is often massive, and even fatal. Our objective is the "in vitro" determination of the results of electrocoagulation applied to a fragment of muscle on the sacral bone surface during rectal resection due to a malignant neoplasm of the rectum. Single-pole coagulation was applied "in vitro" with the selector at maximum power on a 2×2 cms muscle fragment, applied to the anterior side of the IV sacral vertebra until reaching boiling point. The method was used on 6 patients with bleeding of the presacral venous plexus. In the "in vitro" study, boiling point was reached in 90 seconds from applying the single-pole current on the muscle fragment. Electrocoagulation was applied to a 2×2 cm rectal muscle fragment in 6 patients with presacral venous haemorrhage, using pressure on the surface of the presacral bone, with the stopping of the bleeding being achieved in all cases. The use of indirect electrocoagulation on a fragment of the rectus abdominis muscle is a straightforward and highly effective technique for controlling presacral venous haemorrhage. Copyright © 2011 AEC. Published by Elsevier Espana. All rights reserved.

Best estimate plus uncertainty analysis of departure from nucleate boiling limiting case with CASL core simulator VERA-CS in response to PWR main steam line break event

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Cameron S.; Zhang, Hongbin; Kucukboyaci, Vefa

VERA-CS (Virtual Environment for Reactor Applications, Core Simulator) is a coupled neutron transport and thermal-hydraulics subchannel code under development by the Consortium for Advanced Simulation of Light Water Reactors (CASL). VERA-CS was used to simulate a typical pressurized water reactor (PWR) full core response with 17x17 fuel assemblies for a main steam line break (MSLB) accident scenario with the most reactive rod cluster control assembly stuck out of the core. The accident scenario was initiated at the hot zero power (HZP) at the end of the first fuel cycle with return to power state points that were determined by amore » system analysis code and the most limiting state point was chosen for core analysis. The best estimate plus uncertainty (BEPU) analysis method was applied using Wilks’ nonparametric statistical approach. In this way, 59 full core simulations were performed to provide the minimum departure from nucleate boiling ratio (MDNBR) at the 95/95 (95% probability with 95% confidence level) tolerance limit. The results show that this typical PWR core remains within MDNBR safety limits for the MSLB accident.« less

Method of and apparatus for determining deposition-point temperature

DOEpatents

Mansure, A.J.; Spates, J.J.; Martin, S.J.

1998-10-27

Acoustic-wave sensor apparatus and method are disclosed for analyzing a normally liquid petroleum-based composition for monitoring deposition-point temperature. The apparatus includes at least one acoustic-wave device such as SAW, QCM, FPM, TSM or APM type devices in contact with the petroleum-based composition for sensing or detecting the surface temperature at which deposition occurs and/or rate of deposition as a function of temperature by sensing an accompanying change in frequency, phase shift, damping voltage or damping current of an electrical oscillator to a known calibrated condition. The acoustic wave device is actively cooled to monitor the deposition of constituents such as paraffins by determining the point at which solids from the liquid composition begin to form on the acoustic wave device. The acoustic wave device can be heated to melt or boil off the deposits to reset the monitor and the process can be repeated. 5 figs.

Method of and apparatus for determining deposition-point temperature

DOEpatents

Mansure, Arthur J.; Spates, James J.; Martin, Stephen J.

1998-01-01

Acoustic-wave sensor apparatus and method for analyzing a normally liquid petroleum-based composition for monitoring deposition-point temperature. The apparatus includes at least one acoustic-wave device such as SAW, QCM, FPM, TSM or APM type devices in contact with the petroleum-based composition for sensing or detecting the surface temperature at which deposition occurs and/or rate of deposition as a function of temperature by sensing an accompanying change in frequency, phase shift, damping voltage or damping current of an electrical oscillator to a known calibrated condition. The acoustic wave device is actively cooled to monitor the deposition of constituents such as paraffins by determining the point at which solids from the liquid composition begin to form on the acoustic wave device. The acoustic wave device can be heated to melt or boil off the deposits to reset the monitor and the process can be repeated.

High-freezing-point fuels used for aviation turbine engines

NASA Technical Reports Server (NTRS)

Friedman, R.

1979-01-01

Broadened-specification aviation fuels could be produced from a greater fraction of crude source material with improvements in fuel supply and price. These fuels, particularly those with increased final boiling temperatures, would have higher freezing temperatures than current aviation turbine fuels. The higher-freezing-point fuels can be substituted in the majority of present commercial flights, since temperature data indicate that in-flight fuel temperatures are relatively mild. For the small but significant fraction of commercial flights where low fuel temperatures make higher freezing-point fuel use unacceptable, adaptations to the fuel or fuel system may be made to accommodate this fuel. Several techniques are discussed. Fuel heating is the most promising concept. One simple system design uses existing heat rejection from the fuel-lubricating oil cooler, another uses an engine-driven generator for electrical heating. Both systems offer advantages that outweigh the obvious penalties.

Hydrocarbon and nonhydrocarbon derivatives of cyclopropane

NASA Technical Reports Server (NTRS)

Slabey, Vernon A; Wise, Paul H; Gibbons, Louis C

1953-01-01

The methods used to prepare and purify 19 hydrocarbon derivatives of cyclopropane are discussed. Of these hydrocarbons, 13 were synthesized for the first time. In addition to the hydrocarbons, six cyclopropylcarbinols, five alkyl cyclopropyl ketones, three cyclopropyl chlorides, and one cyclopropanedicarboxylate were prepared as synthesis intermediates. The melting points, boiling points, refractive indices, densities, and, in some instances, heats of combustion of both the hydrocarbon and nonhydrocarbon derivatives of cyclopropane were determined. These data and the infrared spectrum of each of the 34 cyclopropane compounds are presented in this report. The infrared absorption bands characteristic of the cyclopropyl ring are discussed, and some observations are made on the contribution of the cyclopropyl ring to the molecular refractions of cyclopropane compounds.

Zero Boil-Off Tank (ZBOT) Experiment

NASA Technical Reports Server (NTRS)

Mcquillen, John

2016-01-01

The Zero-Boil-Off Tank (ZBOT) experiment has been developed as a small scale ISS experiment aimed at delineating important fluid flow, heat and mass transport, and phase change phenomena that affect cryogenic storage tank pressurization and pressure control in microgravity. The experiments use a simulant transparent low boiling point fluid (PnP) in a sealed transparent Dewar to study and quantify: (a) fluid flow and thermal stratification during pressurization; (b) mixing, thermal destratification, depressurization, and jet-ullage penetration during pressure control by jet mixing. The experiment will provide valuable microgravity empirical two-phase data associated with the above-mentioned physical phenomena through highly accurate local wall and fluid temperature and pressure measurements, full-field phase-distribution and flow visualization. Moreover, the experiments are performed under tightly controlled and definable heat transfer boundary conditions to provide reliable high-fidelity data and precise input as required for validation verification of state-of-the-art two-phase CFD models developed as part of this research and by other groups in the international scientific and cryogenic fluid management communities.

Contact angle change during evaporation of near-critical liquids

NASA Astrophysics Data System (ADS)

Nikolayev, Vadim; Hegseth, John; Beysens, Daniel

1998-03-01

An unexpected change of the dynamic contact angle was recently observed in a near-critical liquid-gas system in a space experiment. While the near-critical liquid completely wets a solid under equilibrium conditions, the apparent contact angle changed from 0^circ to about 120^circ during evaporation. We propose an explanation for this phenomenon by taking into account vapor recoil due to evaporation (motion of the vapor from the free liquid surface). This force is normal to the vapor-liquid interface and is directed towards the liquid. It increases sharply near the triple contact line. Near the critical point, where the surface tension force is very weak, the vapor recoil force can be important enough to change the apparent contact angle. A similar effect can also explain the drying of a heater during boiling at high heat flux. The drying greatly reduces the heat transfer to the liquid causing the heater to melt. This phenomenon is called ``boiling crisis", ``burnout" or ``Departure from Nuclear Boiling".

Walks of bubbles on a hot wire in a liquid bath

NASA Astrophysics Data System (ADS)

Duchesne, A.; Caps, H.

2017-05-01

When a horizontal resistive wire is heated up to the boiling point in a subcooled liquid bath, some vapor bubbles nucleate on its surface. The traditional nucleate boiling theory predicts that bubbles generated from active nucleate sites grow up and depart from the heating surface due to buoyancy and inertia. However, we observed here a different behavior: the bubbles slide along the heated wire. In this situation, unexpected regimes are observed; from the simple sliding motion to bubble clustering. We noticed that bubbles could rapidly change their moving direction and may also interact. Finally, we propose an interpretation for both the attraction between the bubbles and the wire and for the motion of the bubbles on the wire in terms of Marangoni effects.

Distribution of Hydroxyl Groups in Kukersite Shale Oil: Quantitative Determination Using Fourier Transform Infrared (FT-IR) Spectroscopy.

PubMed

Baird, Zachariah Steven; Oja, Vahur; Järvik, Oliver

2015-05-01

This article describes the use of Fourier transform infrared (FT-IR) spectroscopy to quantitatively measure the hydroxyl concentrations among narrow boiling shale oil cuts. Shale oil samples were from an industrial solid heat carrier retort. Reference values were measured by titration and were used to create a partial least squares regression model from FT-IR data. The model had a root mean squared error (RMSE) of 0.44 wt% OH. This method was then used to study the distribution of hydroxyl groups among more than 100 shale oil cuts, which showed that hydroxyl content increased with the average boiling point of the cut up to about 350 °C and then leveled off and decreased.

Isolation of tert-alkylphenols from the products of alkylation of phenols

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nesterova, T.N.; Verevkin, S.P.; Rempel', R.D.

1987-08-10

The authors studied the conditions of isolation of tert-amyl-, hexyl-, heptyl-, octyl-, decyl-, and dodecylphenols, and tert-alkylcresols, alkylpyrocatechols, and alkylhydroquinones from alkylation products. The compounds were isolated in all cases from reaction mixtures obtained in presence of cation-exchange resins of the KU-2 type. A preliminary stage, flash evaporation of the reaction mass at 4-13 Pa for 5-15 min, is needed to prevent decomposition of tert-alkylphenols during their isolation from acid reaction mixtures by fractionation. Flash distillation of high-boiling tert-alkylphenols should be conducted in presence of a component lowering the boiling point of the mixture, added in 1:(0.5-1.0) weight ratio ofmore » original mixture to the component.« less

Nanoscale heat transfer and phase transformation surrounding intensely heated nanoparticles

NASA Astrophysics Data System (ADS)

Sasikumar, Kiran

Over the last decade there has been significant ongoing research to use nanoparticles for hyperthermia-based destruction of cancer cells. In this regard, the investigation of highly non-equilibrium thermal systems created by ultrafast laser excitation is a particularly challenging and important aspect of nanoscale heat transfer. It has been observed experimentally that noble metal nanoparticles, illuminated by radiation at the plasmon resonance wavelength, can act as localized heat sources at nanometer-length scales. Achieving biological response by delivering heat via nanoscale heat sources has also been demonstrated. However, an understanding of the thermal transport at these scales and associated phase transformations is lacking. A striking observation made in several laser-heating experiments is that embedded metal nanoparticles heated to extreme temperatures may even melt without an associated boiling of the surrounding fluid. This unusual phase stability is not well understood and designing experiments to understand the physics of this phenomenon is a challenging task. In this thesis, we will resort to molecular dynamics (MD) simulations, which offer a powerful tool to investigate this phenomenon, without assumptions underlying continuum-level model formulations. We present the results from a series of steady state and transient non-equilibrium MD simulations performed on an intensely heated nanoparticle immersed in a model liquid. For small nanoparticles (1-10 nm in diameter) we observe a stable liquid phase near the nanoparticle surface, which can be at a temperature well above the boiling point. Furthermore, we report the existence of a critical nanoparticle size (4 nm in diameter) below which we do not observe formation of vapor even when local fluid temperatures exceed the critical temperature. Instead, we report the existence of a stable fluid region with a density much larger than that of the vapor phase. We explain this stability in terms of the Laplace pressure associated with the formation of a vapor nanocavity and the associated effect on the Gibbs free energy. Separately, we also demonstrate the role of extreme temperature gradients (108-1010 K/m) in elevating the boiling point of liquids. We show that, assuming local thermal equilibrium, the observed elevation of the boiling point is associated with the interplay between the "bulk" driving force for the phase change and surface tension of the liquid-vapor interface that suppresses the transformation. In transient simulations that mimic laser-heating experiments we observe the formation and collapse of vapor bubbles around the nanoparticles beyond a threshold. Detailed analysis of the cavitation dynamics indicates adiabatic formation followed by an isothermal final stage of growth and isothermal collapse.

ChemEd X Data: Exposing Students to Open Scientific Data for Higher-Order Thinking and Self-Regulated Learning

ERIC Educational Resources Information Center

Eklund, Brandon; Prat-Resina, Xavier

2014-01-01

ChemEd X Data is an open web tool that collects and curates physical and chemical data of hundreds of substances. This tool allows students to navigate, select, and graphically represent data such as boiling and melting points, enthalpies of combustion, and heat capacities for hundreds of molecules. By doing so, students can independently identify…

Management by Objectives. NAESP School Leadership Digest Second Series, Number 3. ERIC/CEM Research Analysis Series, Number 18.

ERIC Educational Resources Information Center

Dunn, Pierre

It is possible to remain faithful to the general intentions of management by objectives (MBO) while boiling it down to four major points. First, MBO places the emphasis on results rather than on resources or the ways in which resources are utilized. Second, responsibility for achieving these results is shared jointly by the superior and his…

Determination of the Effect of Various Modes of Cooking on the Vitamin C Content of a Common Food, Green Pepper: An Introductory Biochemistry Experiment.

ERIC Educational Resources Information Center

Johnson, Eric R.

1988-01-01

Describes a laboratory experiment that measures the amount of ascorbic acid destroyed by food preparation methods (boiling and steaming). Points out that aqueous extracts of cooked green pepper samples can be analyzed for ascorbic acid by a relatively simple redox titration. Lists experimental procedure for four methods of preparation. (MVL)

Novel Protein Folding Pathways for Protein Salvage and Recycling

DTIC Science & Technology

2013-08-26

cooperative protein folding and unfolding reactions. Archaea are primitive microorganisms placed by most taxonomic criteria at the base of the Tree of...Life. The Archaea have many molecular properties that are found universally in modern lineages of both Bacteria and Archaea , and many species are...specialized for survival and growth in extreme conditions, including at or above the normal boiling point of water. These hyperthermophilic archaea

Polydimethylsiloxane-based Self healing Composite and Coating Materials

DTIC Science & Technology

2006-01-01

TGA thermogravimetric analysis TDCB tapered double cantilever beam RH relative humidity DMDN-Sn dimethyldineodacanoate tin DBBE-Sn di-n-butyl bis(2...properties of micro-capsules by thermogravimetric analysis (TGA). As shown in figure 2.17, no weight change occurred up to the boiling point of...Elemental analysis of separated prepolymer phase and control samples. ..............24 Table 2.4: The size values of phase separated PDMS droplets

JPRS Report, China.

DTIC Science & Technology

1989-01-19

Order as Guiding Principle 38 Determination, Strategy Termed Essential 39 Changed Perception in Financial Sector 39 Firm Lending Policy 40 On...the state of ecnomic development fully proves this point. If it is said that there are inconsis- tencies between an administrative region and an...relations. Essentially , this problem boils down to the question of how to integrate a public ownership system with a commodity economy. The old public

Woody Biomass Conversion to JP-8 Fuels

DTIC Science & Technology

2014-02-15

Fermentation of Conditioned Extract or Brownstock to Lipids SUB 5 Mixed Culture Fermentation of Mixed-sugars in Raw extract to Mixed Acids SUB 6 TDO...avoiding the need for producing clean simple sugars tluough controlled hydrolysis, and detoxification in a particular case of fermentation ...according to high temperature simulated distillation (ASTM 7169) shown in Figure 5. Figure 5: Boiling point distribution data for raw TDO

Assessing the Feasibility of DNAPL Source Zone Remediation: Review of Case Studies

DTIC Science & Technology

2004-05-01

such as sugars, alcohols, fatty acids that are fermented to hydrogen and used for reductive dechlorination) are more soluble than the chlorinated...addition because a greater percentage of the hydrogen produced during the fermentation of added electron donors is consumed by dechlorinating...Battelle, 2002; Stegemeier and Vinegar , 2001; Roote, 2003; USEPA, 1999): i) increasing vapor pressure and volatilization rates of low boiling point

Aqueous process for recovering sulfur from hydrogen sulfide-bearing gas

DOEpatents

Basu, Arunabha

2015-05-05

A process for recovering sulfur from a hydrogen sulfide-bearing gas utilizes an aqueous reaction medium, a temperature of about 110-150.degree. C., and a high enough pressure to maintain the aqueous reaction medium in a liquid state. The process reduces material and equipment costs and addresses the environmental disadvantages associated with known processes that rely on high boiling point organic solvents.

Liquid paraffin as new dilution medium for the analysis of high boiling point residual solvents with static headspace-gas chromatography.

PubMed

D'Autry, Ward; Zheng, Chao; Bugalama, John; Wolfs, Kris; Hoogmartens, Jos; Adams, Erwin; Wang, Bochu; Van Schepdael, Ann

2011-07-15

Residual solvents are volatile organic compounds which can be present in pharmaceutical substances. A generic static headspace-gas chromatography analysis method for the identification and control of residual solvents is described in the European Pharmacopoeia. Although this method is proved to be suitable for the majority of samples and residual solvents, the method may lack sensitivity for high boiling point residual solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and benzyl alcohol. In this study, liquid paraffin was investigated as new dilution medium for the analysis of these residual solvents. The headspace-gas chromatography method was developed and optimized taking the official Pharmacopoeia method as a starting point. The optimized method was validated according to ICH criteria. It was found that the detection limits were below 1μg/vial for each compound, indicating a drastically increased sensitivity compared to the Pharmacopoeia method, which failed to detect the compounds at their respective limit concentrations. Linearity was evaluated based on the R(2) values, which were above 0.997 for all compounds, and inspection of residual plots. Instrument and method precision were examined by calculating the relative standard deviations (RSD) of repeated analyses within the linearity and accuracy experiments, respectively. It was found that all RSD values were below 10%. Accuracy was checked by a recovery experiment at three different levels. Mean recovery values were all in the range 95-105%. Finally, the optimized method was applied to residual DMSO analysis in four different Kollicoat(®) sample batches. Copyright © 2011 Elsevier B.V. All rights reserved.

Water Quality vs. Sanitation Accessibility: What is the most effective intervention point for preventing cholera in Dhaka, Bangladesh?

NASA Astrophysics Data System (ADS)

Majumder, M. S.; Gute, D.; Faruque, A. S.

2011-12-01

Every year, 3 to 5 million individuals contract cholera, an acute diarrheal infection that is caused by the ingestion of food or water containing the Vibrio cholerae bacterium. Because cholera is a waterborne disease, it can be transmitted quickly in environments with inadequate water and sanitation systems where infected waste can easily pollute drinking water. Today, Bangladesh continues to struggle with endemic cholera. Donor organizations address water and sanitation via localized initiatives, including the installation of community water collection sites (i.e. tubewells; water-boiling points; etc.). At this small-scale level, water quality and sanitation accessibility can be improved independently of one another, and when resources are limited, donors must invest in the most effective disease prevention options. This study used laboratory-confirmed cholera incidence data (2000-2009) collected by the International Centre of Diarrheal Disease Research, Bangladesh at their on-site hospital to compare the efficacy of interventions addressing water quality versus sanitation accessibility in Dhaka, Bangladesh. Data regarding use of sanitary latrines and boiling of drinking water were extracted from sequential patient interviews conducted at the Dhaka facility and used as surrogate variables for sanitation accessibility and water quality respectively. Our analysis indicates that boiling water is 10 times more effective at preventing cholera than the use of a sanitary latrine. This finding suggests that regulating water quality is perhaps more critical to cholera prevention than increasing sanitation accessibility in an urban environment like that of Dhaka. At present, WaterAid - one of Bangladesh's most significant water and sanitation donor organizations - invests the majority of its budget on improving sanitation accessibility. The World Health Organization and the United Nations Millennium Development Goals also prioritize sanitation accessibility. However, in Bangladesh, water quality must be given greater attention. As the nation's most prevalent diarrheal disease, cholera outbreaks result in incalculable lost wages and treatment expenses, taken from the pockets of an already impoverished society. Bangladesh cannot afford cholera; prevention is the only sustainable control option, and water quality is the most effective intervention point for Dhaka, Bangladesh.

A Ghost Fluid/Level Set Method for boiling flows and liquid evaporation: Application to the Leidenfrost effect

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rueda Villegas, Lucia; Alis, Romain; Lepilliez, Mathieu

2016-07-01

The development of numerical methods for the direct numerical simulation of two-phase flows with phase change, in the framework of interface capturing or interface tracking methods, is the main topic of this study. We propose a novel numerical method, which allows dealing with both evaporation and boiling at the interface between a liquid and a gas. Indeed, in some specific situations involving very heterogeneous thermodynamic conditions at the interface, the distinction between boiling and evaporation is not always possible. For instance, it can occur for a Leidenfrost droplet; a water drop levitating above a hot plate whose temperature is muchmore » higher than the boiling temperature. In this case, boiling occurs in the film of saturated vapor which is entrapped between the bottom of the drop and the plate, whereas the top of the water droplet evaporates in contact of ambient air. The situation can also be ambiguous for a superheated droplet or at the contact line between a liquid and a hot wall whose temperature is higher than the saturation temperature of the liquid. In these situations, the interface temperature can locally reach the saturation temperature (boiling point), for instance near a contact line, and be cooler in other places. Thus, boiling and evaporation can occur simultaneously on different regions of the same liquid interface or occur successively at different times of the history of an evaporating droplet. Standard numerical methods are not able to perform computations in these transient regimes, therefore, we propose in this paper a novel numerical method to achieve this challenging task. Finally, we present several accuracy validations against theoretical solutions and experimental results to strengthen the relevance of this new method.« less

Pseudo-critical point in anomalous phase diagrams of simple plasma models

NASA Astrophysics Data System (ADS)

Chigvintsev, A. Yu; Iosilevskiy, I. L.; Noginova, L. Yu

2016-11-01

Anomalous phase diagrams in subclass of simplified (“non-associative”) Coulomb models is under discussion. The common feature of this subclass is absence on definition of individual correlations for charges of opposite sign. It is e.g. modified OCP of ions on uniformly compressible background of ideal Fermi-gas of electrons OCP(∼), or a superposition of two non-ideal OCP(∼) models of ions and electrons etc. In contrast to the ordinary OCP model on non-compressible (“rigid”) background OCP(#) two new phase transitions with upper critical point, boiling and sublimation, appear in OCP(∼) phase diagram in addition to the well-known Wigner crystallization. The point is that the topology of phase diagram in OCP(∼) becomes anomalous at high enough value of ionic charge number Z. Namely, the only one unified crystal- fluid phase transition without critical point exists as continuous superposition of melting and sublimation in OCP(∼) at the interval (Z 1 < Z < Z 2). The most remarkable is appearance of pseudo-critical points at both boundary values Z = Z 1 ≈ 35.5 and Z = Z 2 ≈ 40.0. It should be stressed that critical isotherm is exactly cubic in both these pseudo-critical points. In this study we have improved our previous calculations and utilized more complicated model components equation of state provided by Chabrier and Potekhin (1998 Phys. Rev. E 58 4941).

Unusual Sediment Transportation Processes Under Low Pressure Environments and Implications For Gullies and Recurring Slope Lineae (RSL)

NASA Astrophysics Data System (ADS)

Raack, J.; Herny, C.; Conway, S. J.; Balme, M. R.; Carpy, S.; Patel, M.

2017-12-01

Recently and presently active mass wasting features such as gullies and recurring slope lineae (RSL) are common on the surface of Mars, but their origin and triggering mechanisms are under intense debate. While several active mass wasting features have been linked to sublimation of CO2ice, dry granular flows (avalanches), or a combination of both effects, others have been more closely linked to liquid water or briny outflows (e.g. for RSL). However, liquid water on the surface of Mars is unstable under present-day low pressures and surface temperatures. Nevertheless, numerical modeling and remote sensing data have shown that maximum surface temperatures can exceed the frost point of water and that liquid water could exist on the surface of actual Mars in a transient state. But to explain the observed spatial extent of RSL and recent modification of gullies, it is estimated that relatively large amounts of liquid water are necessary. It is proving challenging to generate such quantities from the atmosphere. In this contribution we explore the potential effects of boiling water (boiling occurs at martian pressures slightly above the frost point of 273 K) on sediment transport. We will present the outcomes of a series of experiments under low surface and water temperatures (between 278 and 297 K, analogous to surface temperatures observed near RSL) and low pressures (between 8 and 11 mbar). We simulate sediment transport by boiling liquid water over a sloping bed of unconsolidated sediment. Our results reveal a suite of unusual and very reactive sediment transportation processes, which are not produced under terrestrial pressures. We will discuss the impact of these unusual sediment transport processes on estimates of water budgets for active mass wasting processes.

Reference Computational Meshing Strategy for Computational Fluid Dynamics Simulation of Departure from Nucleate BoilingReference Computational Meshing Strategy for Computational Fluid Dynamics Simulation of Departure from Nucleate Boiling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pointer, William David

The objective of this effort is to establish a strategy and process for generation of suitable computational mesh for computational fluid dynamics simulations of departure from nucleate boiling in a 5 by 5 fuel rod assembly held in place by PWR mixing vane spacer grids. This mesh generation process will support ongoing efforts to develop, demonstrate and validate advanced multi-phase computational fluid dynamics methods that enable more robust identification of dryout conditions and DNB occurrence.Building upon prior efforts and experience, multiple computational meshes were developed using the native mesh generation capabilities of the commercial CFD code STAR-CCM+. These meshes weremore » used to simulate two test cases from the Westinghouse 5 by 5 rod bundle facility. The sensitivity of predicted quantities of interest to the mesh resolution was then established using two evaluation methods, the Grid Convergence Index method and the Least Squares method. This evaluation suggests that the Least Squares method can reliably establish the uncertainty associated with local parameters such as vector velocity components at a point in the domain or surface averaged quantities such as outlet velocity magnitude. However, neither method is suitable for characterization of uncertainty in global extrema such as peak fuel surface temperature, primarily because such parameters are not necessarily associated with a fixed point in space. This shortcoming is significant because the current generation algorithm for identification of DNB event conditions relies on identification of such global extrema. Ongoing efforts to identify DNB based on local surface conditions will address this challenge« less

Energy storage-boiler tank

NASA Astrophysics Data System (ADS)

Chubb, T. A.; Nemecek, J. J.; Simmons, D. E.

1980-03-01

Activities performed in an effort to demonstrate heat of fusion energy storage in containerized salts are reported. The properties and cycle life characteristics of a eutectic salt having a boiling point of about 385 C (NaCl, KCl, Mg Cl2) were determined. M-terphenyl was chosen as the heat transfer fluid. Compatibility studies were conducted and mild steel containers were selected. The design and fabrication of a 2MWh storage boiler tank are discussed.

Modular control subsystems for use in solar heating systems for multi-family dwellings

NASA Technical Reports Server (NTRS)

1977-01-01

Progress in the development of solar heating modular control subsystems is reported. Circuit design, circuit drawings, and printed circuit board layout are discussed along with maintenance manuals, installation instructions, and verification and acceptance tests. Calculations made to determine the predicted performance of the differential thermostat are given including details and results of tests for the offset temperature, and boil and freeze protect points.

BioSim (trademark) BG Non-Biological Aerosol Simulant

DTIC Science & Technology

2004-11-17

39.5 1.36 1,1- difluoroethane HFA 152a – Not used for pharmaceutical inhalers , is used for personal products Boiling point (-13o F) 63 (psig... 1 BIOSIMTM BG NON-BIOLOGICAL AEROSOL SIMULANT David S. Alburty, Kelly L. Brown, Jennifer L. Dannehl and Andrew E. Page Midwest...BioSafey Level 1 regulations. All of these materials of biological origin pose challenging logistics problems including safety issues, cost

Methodology, Technical Approach and Measurement Techniques for Testing of TPM Thermal Protection Materials in IPM Plasmatrons

DTIC Science & Technology

2000-04-01

system, 8 - experiments on a study of boundary layer spectrum infrared window). before boiling of glass- silicide coating. This simple 3. SAMPLES AND...dependencies of surface temperature of tested materials and make conclusions concerned joint gllass- silicide coating and anode power of generator...obtained using test stagnation point configuration. glass- silicide coating vs anode power of HF-generator. Temperature peak at constant power

Water, something peculiar.

USGS Publications Warehouse

Van Hylckama, T. E. A.

1979-01-01

Some chemical and physical properties of water are discussed and compared with those of other fluids. For instance, the boiling point is much higher than one would expect considering the molecular weight of water. The heat capacity is also much higher but the viscosity is not. The dielectric constant is exceptionally high. These and other properties of water can be explained by the geometry of the water molecule and the structure of water or ice. -Author

High-temperature kilning of southern pine poles, timbers, lumber, and thick veneer

Treesearch

Peter Koch

1973-01-01

At dry-bulb temperatures above the boiling point of water, with large wet-bulb depressions and high air velocities, southern pine prodcuts can be dried quickly. In an impingement-jet kiln at 300o F., veneer 3/8-inch to 5/8-inch thick can be brought to 10 percent moisture content in 40 to 75 minutes. Drying times for lumber arte linearly related...

The United States Air Force Academy Solar Energy Research

DTIC Science & Technology

1980-07-01

controller, ir the solar sy .4tem, is malfunctioning. Put simply, the house will get cold. lf oh cUrs the occupant will notify civil engineering mainte...with this product has been Revere Copper Laminated Panel Sys - trial uses, condenser tubing, electrical of vital assistance in accumulating the tern...Laminated Panel require water temperatures near the additional components Include tubes,. Construction. In the Revere Panel Sys - boiling point,whereas

Method and apparatus for the production of cluster ions

DOEpatents

Friedman, Lewis; Beuhler, Robert J.

1988-01-01

A method and apparatus for the production of cluster ions, and preferably isotopic hydrogen cluster ions is disclosed. A gas, preferably comprising a carrier gas and a substrate gas, is cooled to about its boiling point and expanded through a supersonic nozzle into a region maintained at a low pressure. Means are provided for the generation of a plasma in the gas before or just as it enters the nozzle.

The Metabolism of Tetralin in Fischer 344 Rats

DTIC Science & Technology

1986-04-01

evaluated petroleum and shale-derived JP-5, a jet fuel composed of aliphatic and aromatic hydrocarbons with the majority of the straight-chain...much like gasoline. JP-8 is a mixture of hydrocarbons of intermediate boiling point and volatility and is similar to the civilian jet fuel , A-1. DFM...toxicity of conventional versus shale-derived JP-5 jet fuel : Light microscopy, hematologic, and serum chemistry studies. Toxicol Appl Pharmacol, 57

Laboratory Evaluation of Drop-in Solvent Alternatives to n-Propyl Bromide for Vapor Degreasing

NASA Technical Reports Server (NTRS)

Mitchell, Mark A.; Lowrey, Nikki M.

2012-01-01

Based on this limited laboratory study, solvent blends of trans-1,2 dichloroethylene with HFEs, HFCs, or PFCs appear to be viable alternatives to n-propyl bromide for vapor degreasing. The lower boiling points of these blends may lead to greater solvent loss during use. Additional factors must be considered when selecting a solvent substitute, including stability over time, VOC, GWP, toxicity, and business considerations.

Mixed feed evaporator

DOEpatents

Vakil, Himanshu B.; Kosky, Philip G.

1982-01-01

In the preparation of the gaseous reactant feed to undergo a chemical reaction requiring the presence of steam, the efficiency of overall power utilization is improved by premixing the gaseous reactant feed with water and then heating to evaporate the water in the presence of the gaseous reactant feed, the heating fluid utilized being at a temperature below the boiling point of water at the pressure in the volume where the evaporation occurs.

Method and apparatus for the production of cluster ions

DOEpatents

Friedman, L.; Beuhler, R.J.

A method and apparatus for the production of cluster ions, and preferably isotopic hydrogen cluster ions is disclosed. A gas, preferably comprising a carrier gas and a substrate gas, is cooled to about its boiling point and expanded through a supersonic nozzle into a region maintained at a low pressure. Means are provided for the generation of a plasma in the gas before or just as it enters the nozzle.

Energy storage-boiler tank

NASA Technical Reports Server (NTRS)

Chubb, T. A.; Nemecek, J. J.; Simmons, D. E.

1980-01-01

Activities performed in an effort to demonstrate heat of fusion energy storage in containerized salts are reported. The properties and cycle life characteristics of a eutectic salt having a boiling point of about 385 C (NaCl, KCl, Mg Cl2) were determined. M-terphenyl was chosen as the heat transfer fluid. Compatibility studies were conducted and mild steel containers were selected. The design and fabrication of a 2MWh storage boiler tank are discussed.

The Vertex Version of Weighted Wiener Number for Bicyclic Molecular Structures

PubMed Central

Gao, Wei

2015-01-01

Graphs are used to model chemical compounds and drugs. In the graphs, each vertex represents an atom of molecule and edges between the corresponding vertices are used to represent covalent bounds between atoms. We call such a graph, which is derived from a chemical compound, a molecular graph. Evidence shows that the vertex-weighted Wiener number, which is defined over this molecular graph, is strongly correlated to both the melting point and boiling point of the compounds. In this paper, we report the extremal vertex-weighted Wiener number of bicyclic molecular graph in terms of molecular structural analysis and graph transformations. The promising prospects of the application for the chemical and pharmacy engineering are illustrated by theoretical results achieved in this paper. PMID:26640513

Microbiological hazard identification and exposure assessment of poultry products sold in various localities of Hyderabad, India.

PubMed

Sudershan, Rao V; Naveen Kumar, R; Kashinath, L; Bhaskar, V; Polasa, K

2012-01-01

A study was carried out to identify microbiological hazards and assess their exposure associated with consumption of poultry based street food served in different localities of Hyderabad. The study indicated that chicken 65, chicken fried rice, chicken noodles, chicken Manchuria and chilly chicken are the most common recipes. A process flow diagram was developed to identify critical control points in the food item. After analysis of the samples at each level of preparation, it was observed that rice and noodles were kept at room temperature for about 5-6 hrs which was a critical control point. A total of 376 samples including chicken fried rice, chicken noodles, boiled noodles and boiled rice were collected from circle 1, 2, 3, 4, 5, 6, and 7 of Greater Hyderabad municipal corporation (GHMC) and analyzed for microbiological examination. The most prevalent pathogenic bacteria isolated were S. aureus (3.4 log 10 cfu/g) and B. cereus (3.4 log 10 cfu/g). Salmonella spp. was present in salads (3.2 log 10 cfu/g) and hand washings of the food handler (3.5 log 10 cfu/g). Salmonella contamination was found in salads served along with chicken fried rice and chicken noodles than in the food.

Tandem sulfur chemiluminescence and flame ionization detection with planar microfluidic devices for the characterization of sulfur compounds in hydrocarbon matrices.

PubMed

Luong, J; Gras, R; Shellie, R A; Cortes, H J

2013-07-05

The detection of sulfur compounds in different hydrocarbon matrices, from light hydrocarbon feedstocks to medium synthetic crude oil feeds provides meaningful information for optimization of refining processes as well as demonstration of compliance with petroleum product specifications. With the incorporation of planar microfluidic devices in a novel chromatographic configuration, sulfur compounds from hydrogen sulfide to alkyl dibenzothiophenes and heavier distributions of sulfur compounds over a wide range of matrices spanning across a boiling point range of more than 650°C can be characterized, using one single analytical configuration in less than 25min. In tandem with a sulfur chemiluminescence detector for sulfur analysis is a flame ionization detector. The flame ionization detector can be used to establish the boiling point range of the sulfur compounds in various hydrocarbon fractions for elemental specific simulated distillation analysis as well as profiling the hydrocarbon matrices for process optimization. Repeatability of less than 3% RSD (n=20) over a range of 0.5-1000 parts per million (v/v) was obtained with a limit of detection of 50 parts per billion and a linear range of 0.5-1000 parts per million with a correlation co-efficient of 0.998. Copyright © 2013 Elsevier B.V. All rights reserved.

Temperature-induced unfolding of epidermal growth factor (EGF): insight from molecular dynamics simulation

PubMed Central

Yan, Chunli; Pattani, Varun; Tunnell, James W.; Ren, Pengyu

2010-01-01

Thermal disruption of protein structure and function is a potentially powerful therapeutic vehicle. With the emerging nanoparticle-targeting and femtosecond laser technology, it is possible to deliver heating locally to specific molecules. It is therefore important to understand how fast a protein can unfold or lose its function at high temperatures, such as near the water boiling point. In this study, the thermal damage of EGF was investigated by combining the replica exchange (136 replicas) and conventional molecular dynamics simulations. The REMD simulation was employed to rigorously explore the free energy landscape of EGF unfolding. Interestingly, besides the native and unfolded states, we also observed a distinct molten globule (MG) state that retained substantial amount of native contacts. Based on the understanding that which the unfolding of EGF is a three-state process, we have examined the unfolding kinetics of EGF (N→ MG→h multiple 20-ns conventional MD simulations. The Arrhenius prefactors and activation energy barriers determined from the simulation are within the range of previously studied proteins. In contrast to the thermal damage of cells and tissues which take place on the time scale of seconds to hours at relatively low temperatures, the denaturation of proteins occur in nanoseconds when the temperature of heat bath approaches the boiling point. PMID:20466569

Microbiological Hazard Identification and Exposure Assessment of Poultry Products Sold in Various Localities of Hyderabad, India

PubMed Central

Sudershan, Rao V.; Naveen Kumar, R.; Kashinath, L.; Bhaskar, V.; Polasa, K.

2012-01-01

A study was carried out to identify microbiological hazards and assess their exposure associated with consumption of poultry based street food served in different localities of Hyderabad. The study indicated that chicken 65, chicken fried rice, chicken noodles, chicken Manchuria and chilly chicken are the most common recipes. A process flow diagram was developed to identify critical control points in the food item. After analysis of the samples at each level of preparation, it was observed that rice and noodles were kept at room temperature for about 5-6 hrs which was a critical control point. A total of 376 samples including chicken fried rice, chicken noodles, boiled noodles and boiled rice were collected from circle 1, 2, 3, 4, 5, 6, and 7 of Greater Hyderabad municipal corporation (GHMC) and analyzed for microbiological examination. The most prevalent pathogenic bacteria isolated were S. aureus (3.4 log 10 cfu/g) and B. cereus (3.4 log 10 cfu/g). Salmonella spp. was present in salads (3.2 log 10 cfu/g) and hand washings of the food handler (3.5 log 10 cfu/g). Salmonella contamination was found in salads served along with chicken fried rice and chicken noodles than in the food. PMID:22593705

Cooperative motion in liquids: On librational dynamics of chloroform throughout its normal liquid-phase range

NASA Astrophysics Data System (ADS)

Rothschild, Walter G.; Cavagnat, Raymond M.

1994-03-01

We have extended the Raman spectral accumulations of the ν3 mode (A1, 367 cm-1) of liquid CHCl3-Cl-35 and its simulation in terms of an orientational equilibrium renewal process [W. G. Rothschild, R. M. Cavagnat, and P. Maraval, J. Chem. Phys. 99, 8922 (1993)] to a temperature of 338 K, about the normal boiling point of the system (335 K). The values of the best-fit parameters predict that the orientational motion of liquid chloroform, even at such a relatively high kinetic energy, is described predominantly by libratory states; their lifetime (˜1 ps) is four times longer than that of the free-rotational steps. The character of the orientational motion of the system, when traversing the range of 213 to 338 K from just above its melting to near its boiling point at about atmospheric pressure, reflects the softening of the liquid-cage structure in terms of an increasing dispersion and/or a decreasing value of the mean libration frequency, a lowering of the depth of its potential well, but near-invariance of its lifetime. Simultaneously, there is an approximately twofold increase in the lifetime of the much shorter stages of free-rotational motion. In essence, the system dynamics remain that of an assembly of librators.

Boiling and quenching heat transfer advancement by nanoscale surface modification.

PubMed

Hu, Hong; Xu, Cheng; Zhao, Yang; Ziegler, Kirk J; Chung, J N

2017-07-21

All power production, refrigeration, and advanced electronic systems depend on efficient heat transfer mechanisms for achieving high power density and best system efficiency. Breakthrough advancement in boiling and quenching phase-change heat transfer processes by nanoscale surface texturing can lead to higher energy transfer efficiencies, substantial energy savings, and global reduction in greenhouse gas emissions. This paper reports breakthrough advancements on both fronts of boiling and quenching. The critical heat flux (CHF) in boiling and the Leidenfrost point temperature (LPT) in quenching are the bottlenecks to the heat transfer advancements. As compared to a conventional aluminum surface, the current research reports a substantial enhancement of the CHF by 112% and an increase of the LPT by 40 K using an aluminum surface with anodized aluminum oxide (AAO) nanoporous texture finish. These heat transfer enhancements imply that the power density would increase by more than 100% and the quenching efficiency would be raised by 33%. A theory that links the nucleation potential of the surface to heat transfer rates has been developed and it successfully explains the current finding by revealing that the heat transfer modification and enhancement are mainly attributed to the superhydrophilic surface property and excessive nanoscale nucleation sites created by the nanoporous surface.

Heat transport in bubbling turbulent convection

PubMed Central

Lakkaraju, Rajaram; Stevens, Richard J. A. M.; Oresta, Paolo; Verzicco, Roberto; Lohse, Detlef; Prosperetti, Andrea

2013-01-01

Boiling is an extremely effective way to promote heat transfer from a hot surface to a liquid due to numerous mechanisms, many of which are not understood in quantitative detail. An important component of the overall process is that the buoyancy of the bubble compounds with that of the liquid to give rise to a much-enhanced natural convection. In this article, we focus specifically on this enhancement and present a numerical study of the resulting two-phase Rayleigh–Bénard convection process in a cylindrical cell with a diameter equal to its height. We make no attempt to model other aspects of the boiling process such as bubble nucleation and detachment. The cell base and top are held at temperatures above and below the boiling point of the liquid, respectively. By keeping this difference constant, we study the effect of the liquid superheat in a Rayleigh number range that, in the absence of boiling, would be between 2 × 106 and 5 × 109. We find a considerable enhancement of the heat transfer and study its dependence on the number of bubbles, the degree of superheat of the hot cell bottom, and the Rayleigh number. The increased buoyancy provided by the bubbles leads to more energetic hot plumes detaching from the cell bottom, and the strength of the circulation in the cell is significantly increased. Our results are in general agreement with recent experiments on boiling Rayleigh–Bénard convection. PMID:23696657

Heat transport in bubbling turbulent convection.

PubMed

Lakkaraju, Rajaram; Stevens, Richard J A M; Oresta, Paolo; Verzicco, Roberto; Lohse, Detlef; Prosperetti, Andrea

2013-06-04

Boiling is an extremely effective way to promote heat transfer from a hot surface to a liquid due to numerous mechanisms, many of which are not understood in quantitative detail. An important component of the overall process is that the buoyancy of the bubble compounds with that of the liquid to give rise to a much-enhanced natural convection. In this article, we focus specifically on this enhancement and present a numerical study of the resulting two-phase Rayleigh-Bénard convection process in a cylindrical cell with a diameter equal to its height. We make no attempt to model other aspects of the boiling process such as bubble nucleation and detachment. The cell base and top are held at temperatures above and below the boiling point of the liquid, respectively. By keeping this difference constant, we study the effect of the liquid superheat in a Rayleigh number range that, in the absence of boiling, would be between 2 × 10(6) and 5 × 10(9). We find a considerable enhancement of the heat transfer and study its dependence on the number of bubbles, the degree of superheat of the hot cell bottom, and the Rayleigh number. The increased buoyancy provided by the bubbles leads to more energetic hot plumes detaching from the cell bottom, and the strength of the circulation in the cell is significantly increased. Our results are in general agreement with recent experiments on boiling Rayleigh-Bénard convection.

Density functional theory and molecular dynamics study of the uranyl ion (UO₂)²⁺.

PubMed

Rodríguez-Jeangros, Nicolás; Seminario, Jorge M

2014-03-01

The detection of uranium is very important, especially in water and, more importantly, in the form of uranyl ion (UO₂)²⁺, which is one of its most abundant moieties. Here, we report analyses and simulations of uranyl in water using ab initio modified force fields for water with improved parameters and charges of uranyl. We use a TIP4P model, which allows us to obtain accurate water properties such as the boiling point and the second and third shells of water molecules in the radial distribution function thanks to a fictitious charge that corrects the 3-point models by reproducing the exact dipole moment of the water molecule. We also introduced non-bonded interaction parameters for the water-uranyl intermolecular force field. Special care was taken in testing the effect of a range of uranyl charges on the structure of uranyl-water complexes. Atomic charges of the solvated ion in water were obtained using density functional theory (DFT) calculations taking into account the presence of nitrate ions in the solution, forming a neutral ensemble. DFT-based force fields were calculated in such a way that water properties, such as the boiling point or the pair distribution function stand. Finally, molecular dynamics simulations of a water box containing uranyl cations and nitrate anions are performed at room temperature. The three peaks in the oxygen-oxygen radial distribution function for water were found to be kept in the presence of uranyl thanks to the improvement of interaction parameters and charges. Also, we found three shells of water molecules surrounding the uranyl ion instead of two as was previously thought.

Superheated fuel injection for combustion of liquid-solid slurries

DOEpatents

Robben, Franklin A.

1985-01-01

A method and device for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reduced pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal.

Contact angle change during evaporation of near-critical liquids

NASA Astrophysics Data System (ADS)

Nikolayev, Vadim; Hegseth, John; Beysens, Daniel

1998-11-01

An unexpected change of the dynamic contact angle was recently observed in a near-critical liquid-gas system in a space experiment. While the near-critical liquid completely wets a solid under equilibrium conditions, the apparent contact angle changed from 0^circ to about 120^circ during evaporation. We propose an explanation for this phenomenon by taking into account vapor recoil due to evaporation (motion of the vapor from the free liquid surface). This force is normal to the vapor-liquid interface and is directed towards the liquid. It increases sharply near the triple contact line. Near the critical point, where the surface tension force is very weak, the vapor recoil force can be important enough to change the apparent contact angle. A similar effect can also explain the drying of a heater during boiling at high heat flux. The drying greatly reduces the heat transfer to the liquid causing the heater to melt. This phenomenon is called ``boiling crisis", ``burnout" or ``Departure from Nuclear Boiling". We report the preliminary results of the numerical simulation of the liquid evaporation by the Boundary Element method.

Comparison of point-of-care-compatible lysis methods for bacteria and viruses.

PubMed

Heiniger, Erin K; Buser, Joshua R; Mireles, Lillian; Zhang, Xiaohong; Ladd, Paula D; Lutz, Barry R; Yager, Paul

2016-09-01

Nucleic acid sample preparation has been an especially challenging barrier to point-of-care nucleic acid amplification tests in low-resource settings. Here we provide a head-to-head comparison of methods for lysis of, and nucleic acid release from, several pathogenic bacteria and viruses-methods that are adaptable to point-of-care usage in low-resource settings. Digestion with achromopeptidase, a mixture of proteases and peptidoglycan-specific hydrolases, followed by thermal deactivation in a boiling water bath, effectively released amplifiable nucleic acid from Staphylococcus aureus, Bordetella pertussis, respiratory syncytial virus, and influenza virus. Achromopeptidase was functional after dehydration and reconstitution, even after eleven months of dry storage without refrigeration. Mechanical lysis methods proved to be effective against a hard-to-lyse Mycobacterium species, and a miniature bead-mill, the AudioLyse, is shown to be capable of releasing amplifiable DNA and RNA from this species. We conclude that point-of-care-compatible sample preparation methods for nucleic acid tests need not introduce amplification inhibitors, and can provide amplification-ready lysates from a wide range of bacterial and viral pathogens. Copyright © 2016. Published by Elsevier B.V.

Control of electrothermal heating during regeneration of activated carbon fiber cloth.

PubMed

Johnsen, David L; Mallouk, Kaitlin E; Rood, Mark J

2011-01-15

Electrothermal swing adsorption (ESA) of organic gases generated by industrial processes can reduce atmospheric emissions and allow for reuse of recovered product. Desorption energy efficiency can be improved through control of adsorbent heating, allowing for cost-effective separation and concentration of these gases for reuse. ESA experiments with an air stream containing 2000 ppm(v) isobutane and activated carbon fiber cloth (ACFC) were performed to evaluate regeneration energy consumption. Control logic based on temperature feedback achieved select temperature and power profiles during regeneration cycles while maintaining the ACFC's mean regeneration temperature (200 °C). Energy requirements for regeneration were independent of differences in temperature/power oscillations (1186-1237 kJ/mol of isobutane). ACFC was also heated to a ramped set-point, and the average absolute error between the actual and set-point temperatures was small (0.73%), demonstrating stable control as set-point temperatures vary, which is necessary for practical applications (e.g., higher temperatures for higher boiling point gases). Additional logic that increased the maximum power application at lower ACFC temperatures resulted in a 36% decrease in energy consumption. Implementing such control logic improves energy efficiency for separating and concentrating organic gases for post-desorption liquefaction of the organic gas for reuse.

URANIUM PURIFICATION PROCESS

DOEpatents

Winters, C.E.

1957-11-12

A method for the preparation of a diethyl ether solution of uranyl nitrate is described. Previously the preparation of such ether solutions has been difficult and expensive, since crystalline uranyl nitrate hexahydrate dissolves very slowly in ether. An improved method for effecting such dissolution has been found, and it comprises adding molten uranyl nitrate hexahydrate at a temperature of 65 to 105 deg C to the ether while maintaining the temperature of the ether solvent below its boiling point.

Maximum on the Electrical Conductivity Polytherm of Molten TeCl4

NASA Astrophysics Data System (ADS)

Salyulev, Alexander B.; Potapov, Alexei M.

2017-05-01

The electrical conductivity of molten TeCl4 was measured up to 761K, i.e. 106 degrees above the normal boiling point of the salt. For the first time it was found that TeCl4 electrical conductivity polytherm has a maximum. It was recorded at 705K (κmax=0.245 Sm/cm), whereupon the conductivity decreases as the temperature rises. The activation energy of electrical conductivity was calculated.

Correlation of Chemical Characteristics with Fuel Properties by Gas Chromatography.

DTIC Science & Technology

1981-12-01

Ai2i 788 CORRELATION OF CHEMICAL CHARACTERISTICS WITH FUEL / PROPERTIES BY GAS CHROM ..(U) SOUTHWEST RESEARCH INST SAN ANTONIO TX ARMY FUELS AND...to provide peak resolution comparable to, but somewhat improved over those currently in use at the Aero Propulsion Labora- * tory where similar fuels...Chromatographic Science, Vol. 13, February 1975. 18. Stavinoha, L.L., "Boiling Point Distribution of Gasoline by Gas Chrom - atography," U.S. Army Fuels

The Molecular Structure of the Han-Based Liquid Propellants

DTIC Science & Technology

1990-08-01

Temperature. pressur. and the presence of impurities or Wffixninanrs cause changes in the microcopic otganizAion of the mLixures. The size and stnrcture ok’ thm...unique and anomalous fluid. WVIr a small quantity of an iomc compound is introduced, it causes water molecules to marmrage fnxn their original custer...ehmnolamire. ethyldiethanolamine, and trziehanolamine. The boiling point of the pure, anhydrous, compounds are 89, 161, 246. and 340’ C, respectively

Phase relations and adiabats in boiling seafloor geothermal systems

USGS Publications Warehouse

Bischoff, J.L.; Pitzer, Kenneth S.

1985-01-01

Observations of large salinity variations and vent temperatures in the range of 380-400??C suggest that boiling or two-phase separation may be occurring in some seafloor geothermal systems. Consideration of flow rates and the relatively small differences in density between vapors and liquids at the supercritical pressures at depth in these systems suggests that boiling is occurring under closed-system conditions. Salinity and temperature of boiling vents can be used to estimate the pressure-temperature point in the subsurface at which liquid seawater first reached the two-phase boundary. Data are reviewed to construct phase diagrams of coexisting brines and vapors in the two-phase region at pressures corresponding to those of the seafloor geothermal systems. A method is developed for calculating the enthalpy and entropy of the coexisting mixtures, and results are used to construct adiabats from the seafloor to the P-T two-phase boundary. Results for seafloor vents discharging at 2300 m below sea level indicate that a 385??C vent is composed of a brine (7% NaCl equivalent) in equilibrium with a vapor (0.1% NaCl). Brine constitutes 45% by weight of the mixture, and the fluid first boiled at approximately 1 km below the seafloor at 415??C, 330 bar. A 400??C vent is primarily vapor (88 wt.%, 0.044% NaCl) with a small amount of brine (26% NaCl) and first boiled at 2.9 km below the seafloor at 500??C, 520 bar. These results show that adiabatic decompression in the two-phase region results in dramatic cooling of the fluid mixture when there is a large fraction of vapor. ?? 1985.

Liquid-vapor phase relations in the Si-O system: A calorically constrained van der Waals-type model

NASA Astrophysics Data System (ADS)

Connolly, James A. D.

2016-09-01

This work explores the use of several van der Waals (vW)-type equations of state (EoS) for predicting vaporous phase relations and speciation in the Si-O system, with emphasis on the azeotropic boiling curve of SiO2-rich liquid. Comparison with the observed Rb and Hg boiling curves demonstrates that prediction accuracy is improved if the a-parameter of the EoS, which characterizes vW forces, is constrained by ambient pressure heat capacities. All EoS considered accurately reproduce metal boiling curve trajectories, but absent knowledge of the true critical compressibility factor, critical temperatures remain uncertain by ~500 K. The EoS plausibly represent the termination of the azeotropic boiling curve of silica-rich liquid by a critical point across which the dominant Si oxidation state changes abruptly from the tetravalent state characteristic of the liquid to the divalent state characteristic of the vapor. The azeotropic composition diverges from silica toward metal-rich compositions with increasing temperature. Consequently, silica boiling is divariant and atmospheric loss after a giant impact would enrich residual silicate liquids in reduced silicon. Two major sources of uncertainty in the boiling curve prediction are the heat capacity of silica liquid, which may decay during depolymerization from the near-Dulong-Petit limit heat capacity of the ionic liquid to value characteristic of the molecular liquid, and the unknown liquid affinity of silicon monoxide. Extremal scenarios for these uncertainties yield critical temperatures and compositions of 5200-6200 K and Si1.1O2-Si1.4O2. The lowest critical temperatures are marginally consistent with shock experiments and are therefore considered more probable.

Chemicals identified in human biological media: a data base. Third annual report, October 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cone, M.V.; Baldauf, M.F.; Martin, F.M.

1981-12-01

Part 2 contains the data base in tabular format. There are two sections, the first with records on nondrug substances, and the second with records on drugs. Chemicals in each section are arranged alphabetically by CAS preferred name, CAS registry number, formula, atomic weight, melting point, boiling point, and vapor pressure. Tissues are listed alphabetically with exposure route, analytical method, number of cases, range, and mean - when available in the source document. A variety of information may also be included that is pertinent to the range and mean as well as experimental design, demography, health effects, pathology, morphology, andmore » toxicity. Review articles are included in the data base; however, no data have been extracted from such documents because the original research articles are included.« less

Thermal treatment of low permeability soils using electrical resistance heating

DOE Office of Scientific and Technical Information (OSTI.GOV)

Udell, K.S.

1996-08-01

The acceleration of recovery rates of second phase liquid contaminants from the subsurface during gas or water pumping operations is realized by increasing the soil and ground water temperature. Electrical heating with AC current is one method of increasing the soil and groundwater temperature and has particular applicability to low permeability soils. Several mechanisms have been identified that account for the enhanced removal of the contaminants during electrical heating. These are vaporization of liquid contaminants with low boiling points, temperature-enhanced evaporation rates of semi-volatile components, and removal of residual contaminants by the boiling of residual water. Field scale studies ofmore » electrical heating and fluid extraction show the effectiveness of this technique and its applicability to contaminants found both above and below the water table and within low permeability soils. 10 refs., 8 figs.« less

Specific interface area in a thin layer system of two immiscible liquids with vapour generation at the contact interface

NASA Astrophysics Data System (ADS)

Pimenova, Anastasiya V.; Gazdaliev, Ilias M.; Goldobin, Denis S.

2017-06-01

For well-stirred multiphase fluid systems the mean interface area per unit volume, or “specific interface area” SV, is a significant characteristic of the system state. In particular, it is important for the dynamics of systems of immiscible liquids experiencing interfacial boiling. We estimate the value of parameter SV as a function of the heat influx {\\dot{Q}}V to the system or the average system overheat <Θ> above the interfacial boiling point. The derived results can be reformulated for the case of an endothermic chemical reaction between two liquid reagents with the gaseous form of one of the reaction products. The final results are restricted to the case of thin layers, where the potential gravitational energy of bubbles leaving the contact interface is small compared to their surface tension energy.

Copper vertical micro dendrite fin arrays and their superior boiling heat transfer capability

NASA Astrophysics Data System (ADS)

Wang, Ya-Qiao; Lyu, Shu-Shen; Luo, Jia-Li; Luo, Zhi-Yong; Fu, Yuan-Xiang; Heng, Yi; Zhang, Jian-Hui; Mo, Dong-Chuan

2017-11-01

Micro pin fin arrays have been widely used in electronic cooling, micro reactors, catalyst support, and wettability modification and so on, and a facile way to produce better micro pin fin arrays is demanded. Herein, a simple electrochemical method has been developed to fabricate copper vertical micro dendrite fin arrays (Cu-VMDFA) with controllable shapes, number density and height. High copper sulphate concentration is one key point to make the dendrite stand vertically. Besides, the applied current should rise at an appropriate rate to ensure the copper dendrite can grow vertically on its own. The Cu-VMDFA can significantly enhance the heat transfer coefficient by approximately twice compared to the plain copper surface. The Cu-VMDFA may be widely used in boiling heat transfer areas such as nuclear power plants, electronic cooling, heat exchangers, and so on.

Estimate feedstock processability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Amorelli, A.; Amos, Y.D.; Halsig, C.P.

1992-06-01

Currently, one of the major environmental pressures is to further reduce sulfur levels in middle distillate products. This paper reports that the key to this is understanding reactivities of individual sulfur components in the feedstocks to be treated. The major sulfur species in middle distillates is aromatic compounds, predominantly benzothiophenes and dibenzothiophenes. However, in straight run materials, significant quantities of aliphatic sulfur compounds and further higher boiling benzothiophenes are also expected. Simultaneous simulated distillation with a gas chromatograph microwave-induced plasma atomic emission detector (SIMDIS/AED) is used for middle distillate characterization of sulfur distribution as a function of boiling point. Itmore » is able to discriminate between middle distillate feed types such as cracked and straight run gas oils, and has shown that similar feeds, with different total sulfur contents (unevenly distributed throughout a feedstock), have the same normalized sulfur distribution.« less

Characterization of heavy oil by capillary supercritical fluid chromatography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fuhr, B.J.; Holloway, L.R.; Reichert, C.

1989-01-01

Using supercritical CO/sub 2/ as the mobile phase with a 30m x 100{mu} ID SPB-5 capillary column and temperature of 90{sup 0}C, high boiling fractions of heavy oils could be characterized. A linear restrictor placed as close as possible to the flame ionization detector jet prevented the characteristic spiking often observed in these systems, and also allowed the study of high molecular weight material without plugging of the restrictor. The boiling points of model saturate and aromatic compounds correlate with retention time providing the capability to study heavy oils without exposing them to the high temperature necessary in gas chromatography.more » Individual peaks can be resolved for the n-paraffins in waxes up to C/sub 90/. Primary production, fireflood and steamflood heavy oils and bitumens were compared by this technique.« less

Determination of the δ2H and δ18O of soil water and water in plant matter; RSIL lab code 1700

USGS Publications Warehouse

Revesz, Kinga M.; Buck, Bryan; Coplen, Tyler B.

2012-01-01

The purpose of the Reston Stable Isotope Laboratory lab code 1700 is to determine the δ2H/1H), abbreviated as δ2H, and the δ18O/16O), abbreviated as δ18O, of soil water and water in plant matter. This method is based on the observation that water and toluene form an azeotropic mixture at 84.1 °C. This temperature is substantially lower than the boiling points of water (100 °C) and toluene (110 °C), but water and toluene are immiscible at ambient temperature. The water content of a soil or plant is determined by weighing, drying, and reweighing a small amount of sample. Sufficient sample to collect 3 to 5 milliliters of water after distillation is loaded into a distillation flask. Sufficient toluene is added so that the sample is immersed throughout the entire distillation to minimize evaporation of water, which would affect the δ2H and δ18O values. The mixture of sample and toluene is heated in a flask to its boiling point (84.1 °C) so that water from the sample and toluene can distill together into a specially designed collection funnel. The temperature of 84.1 °C is maintained until the water has been quantitatively transferred to the collection funnel, at which time the temperature is raised to the boiling point of the remaining component (toluene, 110 °C). The collection funnel is maintained at ambient temperature so that the sample water and toluene can be separated physically. After separation, the sample water is purified by addition of paraffin wax to the container with the sample water, capping the container, and heating to approximately 60 °C to melt the wax. Trace amounts of toluene will dissolve in the wax, purifying the sample water for isotopic analysis. The isotopic composition of the purified water is then determined by equilibration with gaseous hydrogen or carbon dioxide, followed by dual-inlet isotope-ratio mass spectrometry. Because laser-absorption spectrometry is sensitive to organic compounds, such as trace toluene remaining in water samples, water samples should be analyzed for isotopic composition only by mass spectrometry and not by laser-absorption spectrometry.

Toward Enhancing Solar Cell Performance: An Effective and "Green" Additive.

PubMed

Tan, Long; Li, Pandeng; Zhang, Qingzhe; Izquierdo, Ricardo; Chaker, Mohamed; Ma, Dongling

2018-02-21

Performance of bulk heterojunction polymer solar cells (PSCs) highly relies on the morphology of the photoactive layer involving conjugated polymers and fullerene derivatives as donors and acceptors, respectively. Herein, butylamine was found to be able to optimize the morphology of the donor/acceptor (D/A) film composed of a blend of poly(3-hexylthiophene-2,5-diyl) (P3HT) and phenyl-C 61 -butyric acid methyl ester (PCBM). Compared to the commonly used alkane dithiols and halogenated additives with high boiling points, butylamine has a much lower boiling point between 77 and 79 °C, and it is also much "greener". A specific interaction between butylamine and PCBM was demonstrated to account for the morphology improvement. Essentially, butylamine can selectively dissolve PCBM in the P3HT:PCBM blend and facilitate the diffusion of PCBM in the film fabrication processes. Atomic force microscopy and X-ray photoelectron spectroscopy investigations confirmed the formation of the P3HT-enriched top surface and the abundance of PCBM at the bottom side, i.e., the formation of vertical phase segregation, as a consequence of the specific PCBM-butylamine interaction. The D/A film with inhomogeneously distributed D and A components in the vertical film direction, with more P3HT at the hole extraction side and more PCBM at the electron extraction side, enables more efficient charge extraction in the D/A film, reflected by the largely enhanced fill factor. The power conversion efficiency of devices reached 4.03 and 4.61%, respectively, depending on the thickness of the D/A film, and these are among the best values reported for P3HT:PCBM-based devices. As compared to the devices fabricated without the introduction of butylamine under otherwise the same processing conditions, they represented 19.6 and 21.6% improvement in the efficiency, respectively. The discovery of butylamine as a new, effective additive in enhancing the performance of PSCs strongly suggests that the differential affinity of additives toward donors and acceptors likely plays a more important role in morphology optimization than their boiling point, different from what was reported previously. The finding provides useful information for realizing large-area PSC fabrication, where a "greener" additive is always preferred.

Solubility of some alkali and alkaline earth chlorides in water at moderate temperatures

USGS Publications Warehouse

Clynne, M.A.; Potter, R.W.

1979-01-01

Solubilities for the binary systems, salt-H2O, of the chlorides of lithium, rubidium, cesium, magnesium, calcium, strontium, and barium from near 0??C to the saturated boiling point are reported. The experimental data and coefficients of an equation for a smoothed curve describing each system are listed in the tables. The data are improvements on those previously reported in the literature, having a precision on the average of ??0.09%.

Excitation of cavitation bubbles in low-temperature liquid nitrogen

NASA Astrophysics Data System (ADS)

Sasaki, Koichi; Harada, Shingo

2017-06-01

We excited a cavitation bubble by irradiating a Nd:YAG laser pulse onto a titanium target that was installed in liquid nitrogen at a temperature below the boiling point. To our knowledge, this is the first experiment in which a cavitation bubble has been successfully excited in liquid nitrogen. We compared the cavitation bubble in liquid nitrogen with that in water on the basis of an equation reported by Florschuetz and Chao [J. Heat Transfer 87, 209 (1965)].

Carbon Dioxide Absorbents

DTIC Science & Technology

1950-05-17

boiling points should be investigated to dotermine the effect of certain structures on the behavior of amines. Only amines which are commercially...ALKANOL ALIPHATIC AMINIES (Contd.) Alkanol Tertiary Amines 141 2-Dinaethylethanolamine (CH3 )2N02 1401 142 2- Diethylethanolamine (02115) 2N0C2 40 143... Diethylethanolamine (C2115)2NC2 1401 143 Triethanolamine (C211401),3N- 144 Ethyl Diethanolamine C2H5N(C2 1401)2 145 Methyl Diethanolamine CH3N(C H401)9

Feasibility of Rectangular Concrete Pressure Vessels for Human Occupancy

DTIC Science & Technology

1990-07-01

incorporated: into the s 1.71 ! -1 rule-. 20 DISTRIBUTION/ AVAILABILIT ’- ,"r ABSTRACT 2’ ABSTRACT SECURITY CLASSIFICATION 7 JUNCLASSIFIED/UNLIMITED 0 SAME AS RPT...carried the end loads. Gas cooled reactors were never very popular in the US. Domestic utilities preferred boiling water reactors that operated at...Point Tower); 1975 - 9,000 psi in Chicago ( Water Tower Place); 1984 - 10,000 psi in Seattle (Century Square Bldg.); 1987 - 10,000 psi in Toronto

Gasification Characterization of Ionic Liquids as Propellants

DTIC Science & Technology

2008-05-25

the droplet is the dominant mode of heat transfer. Furthermore, substantial liquid-phase pyrolytic reaction is initiated when the droplet is heated to...experimental apparatus is shown in Fig. 12. Here a column of a high-boiling-point liquid (Krytox 143AD, a fluorinated oil from DuPont. Density: 1.95 g...6 heating oil (if it were pure, without any volatile component). Because of the very low vapor pressure, the droplet will simply be heated up

Minimum weight passive insulation requirements for hypersonic cruise vehicles.

NASA Technical Reports Server (NTRS)

Ardema, M. D.

1972-01-01

Analytical solutions are derived for two representative cases of the transient heat conduction equation to determine the minimum weight requirements for passive insulation systems of hypersonic cruise vehicles. The cases discussed are the wet wall case with the interior wall temperature held to that of the boiling point of the fuel throughout the flight, and the dry wall case where the heat transferred through the insulation is absorbed by the interior structure whose temperature is allowed to rise.

Generation of standard gas mixtures of halogenated, aliphatic, and aromatic compounds and prediction of the individual output rates based on molecular formula and boiling point.

PubMed

Thorenz, Ute R; Kundel, Michael; Müller, Lars; Hoffmann, Thorsten

2012-11-01

In this work, we describe a simple diffusion capillary device for the generation of various organic test gases. Using a set of basic equations the output rate of the test gas devices can easily be predicted only based on the molecular formula and the boiling point of the compounds of interest. Since these parameters are easily accessible for a large number of potential analytes, even for those compounds which are typically not listed in physico-chemical handbooks or internet databases, the adjustment of the test gas source to the concentration range required for the individual analytical application is straightforward. The agreement of the predicted and measured values is shown to be valid for different groups of chemicals, such as halocarbons, alkanes, alkenes, and aromatic compounds and for different dimensions of the diffusion capillaries. The limits of the predictability of the output rates are explored and observed to result in an underprediction of the output rates when very thin capillaries are used. It is demonstrated that pressure variations are responsible for the observed deviation of the output rates. To overcome the influence of pressure variations and at the same time to establish a suitable test gas source for highly volatile compounds, also the usability of permeation sources is explored, for example for the generation of molecular bromine test gases.

Vaporization and recondensation dynamics of indocyanine green-loaded perfluoropentane droplets irradiated by a short pulse laser

NASA Astrophysics Data System (ADS)

Yu, Jaesok; Chen, Xucai; Villanueva, Flordeliza S.; Kim, Kang

2016-12-01

Phase-transition droplets have been proposed as promising contrast agents for ultrasound and photoacoustic imaging. Short pulse laser activated perfluorocarbon-based droplets, especially when in a medium with a temperature below their boiling point, undergo phase changes of vaporization and recondensation in response to pulsed laser irradiation. Here, we report and discuss the vaporization and recondensation dynamics of perfluoropentane droplets containing indocyanine green in response to a short pulsed laser with optical and acoustic measurements. To investigate the effect of temperature on the vaporization process, an imaging chamber was mounted on a temperature-controlled water reservoir and then the vaporization event was recorded at 5 million frames per second via a high-speed camera. The high-speed movies show that most of the droplets within the laser beam area expanded rapidly as soon as they were exposed to the laser pulse and immediately recondensed within 1-2 μs. The vaporization/recondensation process was consistently reproduced in six consecutive laser pulses to the same area. As the temperature of the media was increased above the boiling point of the perfluoropentane, the droplets were less likely to recondense and remained in a gas phase after the first vaporization. These observations will help to clarify the underlying processes and eventually guide the design of repeatable phase-transition droplets as a photoacoustic imaging contrast agent.

Determination of boiling point of petrochemicals by gas chromatography-mass spectrometry and multivariate regression analysis of structural activity relationship.

PubMed

Fakayode, Sayo O; Mitchell, Breanna S; Pollard, David A

2014-08-01

Accurate understanding of analyte boiling points (BP) is of critical importance in gas chromatographic (GC) separation and crude oil refinery operation in petrochemical industries. This study reported the first combined use of GC separation and partial-least-square (PLS1) multivariate regression analysis of petrochemical structural activity relationship (SAR) for accurate BP determination of two commercially available (D3710 and MA VHP) calibration gas mix samples. The results of the BP determination using PLS1 multivariate regression were further compared with the results of traditional simulated distillation method of BP determination. The developed PLS1 regression was able to correctly predict analytes BP in D3710 and MA VHP calibration gas mix samples, with a root-mean-square-%-relative-error (RMS%RE) of 6.4%, and 10.8% respectively. In contrast, the overall RMS%RE of 32.9% and 40.4%, respectively obtained for BP determination in D3710 and MA VHP using a traditional simulated distillation method were approximately four times larger than the corresponding RMS%RE of BP prediction using MRA, demonstrating the better predictive ability of MRA. The reported method is rapid, robust, and promising, and can be potentially used routinely for fast analysis, pattern recognition, and analyte BP determination in petrochemical industries. Copyright © 2014 Elsevier B.V. All rights reserved.

Hydrodistillation extraction time effect on essential oil yield, composition, and bioactivity of coriander oil.

PubMed

Zheljazkov, Valtcho D; Astatkie, Tess; Schlegel, Vicki

2014-01-01

Coriander (Coriandrum sativum L.) is a major essential oil crop grown throughout the world. Coriander essential oil is extracted from coriander fruits via hydrodistillation, with the industry using 180-240 min of distillation time (DT), but the optimum DT for maximizing essential oil yield, composition of constituents, and antioxidant activities are not known. This research was conducted to determine the effect of DT on coriander oil yield, composition, and bioactivity. The results show that essential oil yield at the shorter DT was low and generally increased with increasing DT with the maximum yields achieved at DT between 40 and 160 min. The concentrations of the low-boiling point essential oil constituents: α-pinene, camphene, β-pinene, myrcene, para-cymene, limonene, and γ-terpinene were higher at shorter DT (< 2.5 min) and decreased with increasing DT; but the trend reversed for the high-boiling point constituents: geraniol and geranyl-acetate. The concentration of the major essential oil constituent, linalool, was 51% at DT 1.15 min, and increased steadily to 68% with increasing DT. In conclusion, 40 min DT is sufficient to maximize yield of essential oil; and different DT can be used to obtain essential oil with differential composition. Its antioxidant capacity was affected by the DT, with 20 and 240 min DT showing higher antioxidant activity. Comparisons of coriander essential oil composition must consider the length of the DT.

Smoothed particle hydrodynamics simulations of evaporation and explosive boiling of liquid drops in microgravity.

PubMed

Sigalotti, Leonardo Di G; Troconis, Jorge; Sira, Eloy; Peña-Polo, Franklin; Klapp, Jaime

2015-07-01

The rapid evaporation and explosive boiling of a van der Waals (vdW) liquid drop in microgravity is simulated numerically in two-space dimensions using the method of smoothed particle hydrodynamics. The numerical approach is fully adaptive and incorporates the effects of surface tension, latent heat, mass transfer across the interface, and liquid-vapor interface dynamics. Thermocapillary forces are modeled by coupling the hydrodynamics to a diffuse-interface description of the liquid-vapor interface. The models start from a nonequilibrium square-shaped liquid of varying density and temperature. For a fixed density, the drop temperature is increased gradually to predict the point separating normal boiling at subcritical heating from explosive boiling at the superheat limit for this vdW fluid. At subcritical heating, spontaneous evaporation produces stable drops floating in a vapor atmosphere, while at near-critical heating, a bubble is nucleated inside the drop, which then collapses upon itself, leaving a smaller equilibrated drop embedded in its own vapor. At the superheat limit, unstable bubble growth leads to either fragmentation or violent disruption of the liquid layer into small secondary drops, depending on the liquid density. At higher superheats, explosive boiling occurs for all densities. The experimentally observed wrinkling of the bubble surface driven by rapid evaporation followed by a Rayleigh-Taylor instability of the thin liquid layer and the linear growth of the bubble radius with time are reproduced by the simulations. The predicted superheat limit (T(s)≈0.96) is close to the theoretically derived value of T(s)=1 at zero ambient pressure for this vdW fluid.

Full evaporation headspace gas chromatography for sensitive determination of high boiling point volatile organic compounds in low boiling matrices.

PubMed

Mana Kialengila, Didi; Wolfs, Kris; Bugalama, John; Van Schepdael, Ann; Adams, Erwin

2013-11-08

Determination of volatile organic components (VOC's) is often done by static headspace gas chromatography as this technique is very robust and combines easy sample preparation with good selectivity and low detection limits. This technique is used nowadays in different applications which have in common that they have a dirty matrix which would be problematic in direct injection approaches. Headspace by nature favors the most volatile compounds, avoiding the less volatile to reach the injector and column. As a consequence, determination of a high boiling solvent in a lower boiling matrix becomes challenging. Determination of VOCs like: xylenes, cumene, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMA), N-methyl-2-pyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone (DMI), benzyl alcohol (BA) and anisole in water or water soluble products are an interesting example of the arising problems. In this work, a headspace variant called full evaporation technique is worked out and validated for the mentioned solvents. Detection limits below 0.1 μg/vial are reached with RSD values below 10%. Mean recovery values ranged from 92.5 to 110%. The optimized method was applied to determine residual DMSO in a water based cell culture and DMSO and DMA in tetracycline hydrochloride (a water soluble sample). Copyright © 2013 Elsevier B.V. All rights reserved.

Correlation of materials properties with the atomic density concept

NASA Technical Reports Server (NTRS)

1975-01-01

Based on the hypothesis that the number of atoms per unit volume, accurately calculable for any substance of known real density and chemical composition, various characterizing parameters (energy levels of electrons interacting among atoms of the same or different kinds, atomic mass, bond intensity) were chosen for study. A multiple exponential equation was derived to express the relationship. Various properties were examined, and correlated with the various parameters. Some of the properties considered were: (1) heat of atomization, (2) boiling point, (3) melting point, (4) shear elastic modulus of cubic crystals, (5) thermal conductivity, and (6) refractive index for transparent substances. The solid elements and alkali halides were the materials studied. It is concluded that the number of different properties can quantitively be described by a common group of parameters for the solid elements, and a wide variety of compounds.

Influence of different extraction methods on the yield and linalool content of the extracts of Eugenia uniflora L.

PubMed

Galhiane, Mário S; Rissato, Sandra R; Chierice, Gilberto O; Almeida, Marcos V; Silva, Letícia C

2006-09-15

This work has been developed using a sylvestral fruit tree, native to the Brazilian forest, the Eugenia uniflora L., one of the Mirtaceae family. The main goal of the analytical study was focused on extraction methods themselves. The method development pointed to the Clevenger extraction as the best yield in relation to SFE and Soxhlet. The SFE method presented a good yield but showed a big amount of components in the final extract, demonstrating low selectivity. The essential oil extracted was analyzed by GC/FID showing a large range of polarity and boiling point compounds, where linalool, a widely used compound, was identified. Furthermore, an analytical solid phase extraction method was used to clean it up and obtain separated classes of compounds that were fractionated and studied by GC/FID and GC/MS.

Calibration sets selection strategy for the construction of robust PLS models for prediction of biodiesel/diesel blends physico-chemical properties using NIR spectroscopy

NASA Astrophysics Data System (ADS)

Palou, Anna; Miró, Aira; Blanco, Marcelo; Larraz, Rafael; Gómez, José Francisco; Martínez, Teresa; González, Josep Maria; Alcalà, Manel

2017-06-01

Even when the feasibility of using near infrared (NIR) spectroscopy combined with partial least squares (PLS) regression for prediction of physico-chemical properties of biodiesel/diesel blends has been widely demonstrated, inclusion in the calibration sets of the whole variability of diesel samples from diverse production origins still remains as an important challenge when constructing the models. This work presents a useful strategy for the systematic selection of calibration sets of samples of biodiesel/diesel blends from diverse origins, based on a binary code, principal components analysis (PCA) and the Kennard-Stones algorithm. Results show that using this methodology the models can keep their robustness over time. PLS calculations have been done using a specialized chemometric software as well as the software of the NIR instrument installed in plant, and both produced RMSEP under reproducibility values of the reference methods. The models have been proved for on-line simultaneous determination of seven properties: density, cetane index, fatty acid methyl esters (FAME) content, cloud point, boiling point at 95% of recovery, flash point and sulphur.

Experimental investigation on fuel properties of biodiesel prepared from cottonseed oil

NASA Astrophysics Data System (ADS)

Payl, Ashish Naha; Mashud, Mohammad

2017-06-01

In recent time's world's energy demands are satisfied by coal, natural gas as well as petroleum though the prices of these are escalating. If this continues, global recession is unavoidable and diminution of world reserve accelerates undoubtedly. Recently, Biodiesel is found to be more sustainable, non-toxic and energy efficient alternative which is also biodegradable. The use of biofuels in compression ignition engines is now a contemplation attention in place of petrochemicals. In view of this, cottonseed oil is quite a favorable candidate as an alternative fuel. The present study covers the various aspects of biodiesels fuel prepared from cottonseed oil. In this work Biodiesel was prepared from cottonseed oil through transesterification process with methanol, using sodium hydroxide as catalyst. The fuel properties of cottonseed oil methyl esters, kinematic viscosity, flash point, density, calorific value, boiling point etc. were evaluated and discussed in the light of Conventional Diesel Fuel. The properties of biodiesel produced from cotton seed oil are quite close to that of diesel except from flash point. And so the methyl esters of cottonseed oil can be used in existing diesel engines without any modifications.

Hindered Glymes for Graphite-Compatible Electrolytes.

PubMed

Shanmukaraj, Devaraj; Grugeon, Sylvie; Laruelle, Stephane; Armand, Michel

2015-08-24

Organic carbonate mixtures are used almost exclusively as lithium battery electrolyte solvents. The linear compounds (dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate) act mainly as thinner for the more viscous and high-melting ethylene carbonate but are the least stable component and have low flash points; these are serious handicaps for lifetime and safety. Polyethers (glymes) are useful co-solvents, but all formerly known representatives solvate Li(+) strongly enough to co-intercalate in the graphite negative electrode and exfoliate it. We have put forward a new electrolyte composition comprising a polyether to which a bulky tert-butyl group is attached ("hindered glyme"), thus completely preventing co-intercalation while maintaining good conductivity. This alkyl-carbonate-free electrolyte shows remarkable cycle efficiency of the graphite electrode, not only at room temperature, but also at 50 and 70 °C in the presence of lithium bis(fluorosulfonimide). The two-ethylene-bridge hindered glyme has a high boiling point and a flash point of 80 °C, a considerable advantage for safety. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Insulation Test Cryostat with Lift Mechanism

NASA Technical Reports Server (NTRS)

Dokos, Adam G. (Inventor); Fesmire, James E. (Inventor)

2014-01-01

A multi-purpose, cylindrical thermal insulation test apparatus is used for testing insulation materials and systems of materials using a liquid boil-off calorimeter system for absolute measurement of the effective thermal conductivity (k-value) and heat flux of a specimen material at a fixed environmental condition (cold-side temperature, warm-side temperature, vacuum pressure level, and residual gas composition). The apparatus includes an inner vessel for receiving a liquid with a normal boiling point below ambient temperature, such as liquid nitrogen, enclosed within a vacuum chamber. A cold mass assembly, including the upper and lower guard chambers and a middle test vessel, is suspended from a lid of the vacuum canister. Each of the three chambers is filled and vented through a single feedthrough. All fluid and instrumentation feedthroughs are mounted and suspended from a top domed lid to allow easy removal of the cold mass. A lift mechanism allows manipulation of the cold mass assembly and insulation test article.

Insulation Test Cryostat with Lift Mechanism

NASA Technical Reports Server (NTRS)

Fesmire, James E. (Inventor); Dokos, Adam G. (Inventor)

2016-01-01

A multi-purpose, cylindrical thermal insulation test apparatus is used for testing insulation materials and systems of materials using a liquid boil-off calorimeter system for absolute measurement of the effective thermal conductivity (k-value) and heat flux of a specimen material at a fixed environmental condition (cold-side temperature, warm-side temperature, vacuum pressure level, and residual gas composition). An inner vessel receives liquid with a normal boiling point below ambient temperature, such as liquid nitrogen, enclosed within a vacuum chamber. A cold mass assembly, including upper and lower guard chambers and middle test vessel, is suspended from a lid of the vacuum canister. Each of the three chambers is filled and vented through a single feedthrough. All fluid and instrumentation feedthroughs are mounted and suspended from a top domed lid allowing easy removal of the cold mass. A lift mechanism allows manipulation of the cold mass assembly and insulation test article.

A Low Cost, Self Acting, Liquid Hydrogen Boil-Off Recovery System

NASA Technical Reports Server (NTRS)

Pelfrey, Joy W.; Sharp, Kirk V. (Technical Monitor)

2001-01-01

The purpose of this research was to develop a prototype liquid hydrogen boll-off recovery system. Perform analyses to finalize recovery system cycle, design detail components, fabricate hardware, and conduct sub-component, component, and system level tests leading to the delivery of a prototype system. The design point and off-design analyses identified cycle improvements to increase the robustness of the system by adding a by-pass heat exchanger. Based on the design, analysis, and testing conducted, the recovery system will liquefy 31% of the gaseous boil off from a liquid hydrogen storage tank. All components, including a high speed, miniature turbocompressor, were designed and manufacturing drawings were created. All hardware was fabricated and tests were conducted in air, helium, and hydrogen. Testing validated the design, except for the turbocompressor. A rotor-to-stator clearance issue was discovered as a result of a concentricity tolerance stack-up.

Superheated fuel injection for combustion of liquid-solid slurries

DOEpatents

Robben, F.A.

1984-10-19

A method and device are claimed for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reduced pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal. 2 figs., 2 tabs.

Multipurpose Thermal Insulation Test Apparatus

NASA Technical Reports Server (NTRS)

Fesmire, James E. (Inventor); Augustynowicz, Stanislaw D. (Inventor)

2002-01-01

A multi-purpose thermal insulation test apparatus is used for testing insulation materials, or other components. The test apparatus is a fluid boil-off calorimeter system for calibrated measurement of the apparent thermal conductivity (k-value) of a specimen material at a fixed vacuum level. The apparatus includes an inner vessel for receiving a fluid with a normal boiling point below ambient temperature, such as liquid nitrogen, enclosed within a vacuum chamber. A cold mass assembly, including the inner vessel and thermal guards, is suspended from the top of the vacuum chamber. Handling tools attach to the cold mass assembly for convenient manipulation of the assembly and for the installation or wrapping of insulation test materials. Liquid nitrogen is typically supplied to the inner vessel using a fill tube with funnel. A single port through the top of the vacuum chamber facilitates both filling and venting. Aerogel composite stacks with reflective films are fastened to the top and the bottom of the inner vessel as thermal guards. The comparative k-value of the insulation material is determined by measuring the boil-off flow rate of gas, the temperature differential across the insulation thickness, and the dimensions (length and diameters) of the test specimen.

The decrease of cylindrical pempek quality during boiling

NASA Astrophysics Data System (ADS)

Karneta, R.; Gultom, N. F.

2017-09-01

The research objective was to study the effects of temperature and formulation on quality of pempek lenjer during boiling. Treatments in this study were four levels of pempek formulation and five levels of temperature. Data was processed by using analysis of variance (Anova). If test results showed that samples were significantly different or highly significantly different, then further test was conducted by using Honestly Significant Different. The results showed that chemical analysis showed that fish dominant formula of cylindrical pempek had higher water content, protein content, lipid content and ash content than that of tapioca starch dominant formula, but it had lower carbohydrate content and fibre content than that of tapioca starch dominant formula.The higher the temperature at center point of cylindrical pempek, the lower the chemical quality of cylindrical pempek. The effect of formula on physical quality of cylindrical pempek showed that tapioca starch dominant formula had more rubbery texture, more neutral pH and brighter color than that of fish dominant formula.The temperature change had no significant effect on texture and pH of cylindrical pempek, but it had significant effect on lightness, intensity and chromatic color especially after exceeding optimum time of boiling.

Insight into Hydrazinium Nitrates, Azides, Dicyanamide, and 5-Azidotetrazolate Ionic Materials from Simulations and Experiments

DTIC Science & Technology

2011-04-04

agreement between simulation and experiment is seen for UDMH , with simulations up to slightly above the boiling point of 336 K falling within a density ...conjunction wi th M05-2X density funct ional. Inclusion of a l one-pair on hydrazinium-based cations significantly improved ion electrostatic description...cation-anion complexes employing aug-cc- pvDz (cc-pvTz) basis functions at MP2 level or in conjunction with M05-2X density functional. Inclusion of

Toxic Hazards Research Unit Annual Technical Report: 1976

DTIC Science & Technology

1976-09-01

1miiethylliydrazine ( UDMH ) 46 Toxicity of Solid Rocket Motor Exchiange - Effects of HCI, HF and Alumina on Rodents 53 Toxicity of High Density jet... Formula C12H20 C14 H20 C714 Molecular Weight 164 188 98 Boiling Point (OF) 431 522 213 Vapor Pressure (70 F) 0.354 mm Hg 0.025 mm Hg 42 mm Hg Density ...Inhalation Exposure of Animals to Coal Tar Aerosol 20 A Six-Month Chronic Inhalation Exposure of Animals to UDMH to Determine Its Oncogenic Capacity

The Development of Oil Incendiary Bombs

DTIC Science & Technology

1942-02-07

fire to wooden structures, such as attics, and markedly superior to four pound thormate bombs. Rubber gels and soap gels arc equally good in non...tures. Gasolines or naphthas having final boiling points of from 250 to 500°F. when properly thickened v.’ith rubber or soaps, do not flash burn nor...thickening t gents* h.’ve shown that (1) if rubber is used, less l.- tex than crope or smoked 3hoet is required for t ^iven degree of thickening, (2

Liquefaction sites, Imperial Valley, California.

USGS Publications Warehouse

Youd, T.L.; Bennett, M.J.

1983-01-01

Sands that did and did not liquefy at two sites during the 1979 Imperial Valley, Calif., earthquake (ML = 6.6) are identified and their properties evaluated. SPT tests were used to evaluate liquefaction susceptibility. Loose fine sands in an abandoned channel liquefied and produced sand boils, ground fissures, and a lateral spread at the Heber Road sites. Evidence of liquefaction was not observed over moderately dense over-bank sand east of the channel nor over dense point-bar sand to the west. -from ASCE Publications Information

Development of a mathematical model for the dissolution of uranium dioxide. II. Statistical model for the dissolution of uranium dioxide tablets in nitric acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhukovskii, Yu.M.; Luksha, O.P.; Nenarokomov, E.A.

1988-03-01

We have derived a statistical model for the dissolution of uranium dioxide tablets for the 6 to 12 M concentration range and temperatures from 80/sup 0/C to the boiling point. The model differs qualitatively from the dissolution model for ground uranium dioxide. In the indicated range of experimental conditions, the mean-square deviation of the curves for the model from the experimental curves is not greater than 6%.

New Technique for Cryogenically Cooling Small Test Articles

NASA Technical Reports Server (NTRS)

Rodriquez, Karen M.; Henderson, Donald J.

2011-01-01

Convective heat removal techniques to rapidly cool small test articles to Earth-Moon L2 temperatures of 77 K were accomplished through the use of liquid nitrogen (LN2). By maintaining a selected pressure range on the saturation curve, test articles were cooled below the LN2 boiling point at ambient pressure in less than 30 min. Difficulties in achieving test pressures while maintaining the temperature tolerance necessitated a modification to the original system to include a closed loop conductive cold plate and cryogenic shroud

A Continued Study of Optical Sound Generation and Amplification

DTIC Science & Technology

1987-10-31

compared to the output of a PVDF hydrophone as shown in Figure 1.2. Given the inaccuracies in beam size estimates, the agreement between theory and...on this curve which are separated by two regions of constant acoustic amplitude. The first extends from zero to 75 jiJ. The boiling point of CS2 is...the general shape of the experimental curves . Figure 1.5 shows the magnitude of the probe beam deflection versus time for propanol. Hutchins and Tam

49 CFR 173.121 - Class 3-Assignment of packing group.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-cup) Initial boiling point I ≤35°C (95 °F) II 35 °C (95 °F) III ≥23 °C, ≤60 °C (≥73 °F, ≤140 °F) >35... determined at 23 °C (73.4 °F) using the ISO standard cup with a 4 mm (0.16 inch) jet as set forth in ISO 2431... carried out using the ISO standard cup with a 6 mm (0.24 inch) jet. (ii) Solvent Separation Test. This...

Catalytic hydrotreating of bio-oil derived from Chlorococcum sp.

NASA Astrophysics Data System (ADS)

Subagyono, R. R. D. J. N.; Marshall, M.; Jackson, W. R.; Chaffee, A. L.

2018-04-01

Hydrotreating of bio-oil derived from Chlorococcum sp. in the absence of NiMo/Al-SBA-15 catalysts has been investigated. The silica alumina supports decreased product yields (DCM solubles and hydrocarbon gases) due to severe coking. Incorporation of NiMo increased the product yields to up to 65 wt.% and increased the proportion of products in the kerosene boiling point range (C12-C17).The superiority of the high acidity supports persisted after incorporation of NiMo.

Gas separation by composite solvent-swollen membranes

DOEpatents

Matson, S.L.; Lee, E.K.L.; Friesen, D.T.; Kelly, D.J.

1989-04-25

There is disclosed a composite immobilized liquid membrane of a solvent-swollen polymer and a microporous organic or inorganic support, the solvent being at least one highly polar solvent containing at least one nitrogen, oxygen, phosphorus or sulfur atom, and having a boiling point of at least 100 C and a specified solubility parameter. The solvent or solvent mixture is homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. The membrane is suitable for acid gas scrubbing and oxygen/nitrogen separation. 3 figs.

Gas separation by composite solvent-swollen membranes

DOEpatents

Matson, Stephen L.; Lee, Eric K. L.; Friesen, Dwayne T.; Kelly, Donald J.

1989-01-01

There is disclosed a composite immobulized liquid membrane of a solvent-swollen polymer and a microporous organic or inorganic support, the solvent being at least one highly polar solvent containing at least one nitrogen, oxygen, phosphorous or sulfur atom, and having a boiling point of at least 100.degree. C. and a specified solubility parameter. The solvent or solvent mixture is homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. The membrane is suitable for acid gas scrubbing and oxygen/nitrogen separation.

Purchase of Microwave Reactors for Implementation of Small-scale Microwave-accelerated Organic Chemistry Laboratory Program in Undergraduate Curriculum and Synthetic Chemistry Research at HU

DTIC Science & Technology

2015-05-16

synthesis of iron magnetic nanoparticles is being investigated (Appendix A; Scheme IV). In the first step, precursor iron(III) chloride nanoparticles...and other methods. Currently, we are developing a two-step scheme for the synthesis of esters that will require distillation and/or column...recognize the link between them. We are developing for the above purpose, the microwave-assisted, two-step synthesis of high boiling point esters. The

Comparison of Medium Power Hall Effect Thruster Ion Acceleration for Krypton and Xenon Propellants

DTIC Science & Technology

2016-09-14

Concentration ppb 87 1000 Stable Isotopes 9 6 Odd Isotopes 2 1 Critical Pressure MPa 5.84 5.50 Critical Temperature K 290 209 Boiling Point (1 atm) K 161 120...The velocity profile in Fig. 6 shows the velocities slightly negative, nearest the anode (at approximately - 9 mm). This negative velocity near the...Krypton and Xenon Propellants 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6 . AUTHOR(S) William A. Hargus, Jr.; Gregory M. Azarnia; Michael R

A Study of the Nephrotoxicity and Metabolism of Tetralin and Indan in Fischer 344 Rats

DTIC Science & Technology

1989-05-01

5, a jet fuel composed of aliphatic and aromatic hydrocarbons with the majority of the straight-chain hydrocarbons being between C10 and C15...hydrocarbon of intermediate boiling point and volatility and is similar to the civilian jet fuel , A-1. DFM is a mixture of long chain aliphatic...to compliment earlier research on jet fuel , JP-10, cis- and trans- decalin, and tetralin, it was anticipated some enlightenment could be obtained on

A Study of the Nephrotoxicity and Metabolism of Tetralin and Indan in Fischer 344 Rats.

DTIC Science & Technology

1988-02-08

evaluated petroleum and shale-derived JP-5, a jet fuel composed of aliphatic and aromatic hydrocarbons with the majority of the straight-chain hydrocarbons...much like gasoline. JP-8 is a mixture of hydrocarbon of intermediate boiling point and volatility and is similar to the civilian jet fuel , A-1. DFM is a...conventional versus shale-derived JP-5 jet fuel : Light microscopy, hematologic, and serum chemistry studies. Toxicol Appl Pharmacol, 57, 302-317 (1981

Microgravity

NASA Image and Video Library

2004-04-15

Fluid Physics is study of the motion of fluids and the effects of such motion. When a liquid is heated from the bottom to the boiling point in Earth's microgravity, small bubbles of heated gas form near the bottom of the container and are carried to the top of the liquid by gravity-driven convective flows. In the same setup in microgravity, the lack of convection and buoyancy allows the heated gas bubbles to grow larger and remain attached to the container's bottom for a significantly longer period.

Effect of Running Parameters on Flow Boiling Instabilities in Microchannels.

PubMed

Zong, Lu-Xiang; Xu, Jin-Liang; Liu, Guo-Hua

2015-04-01

Flow boiling instability (FBI) in microchannels is undesirable because they can induce the mechanical vibrations and disturb the heat transfer characteristics. In this study, the synchronous optical visualization experimental system was set up. The pure acetone liquid was used as the working fluid, and the parallel triangle silicon microchannel heat sink was designed as the experimental section. With the heat flux ranging from 0-450 kW/m2 the microchannel demand average pressure drop-heater length (Δp(ave)L) curve for constant low mass flux, and the demand pressure drop-mass flux (Δp(ave)G) curve for constant length on main heater surface were obtained and studied. The effect of heat flux (q = 188.28, 256.00, and 299.87 kW/m2), length of main heater surface (L = 4.5, 6.25, and 8.00 mm), and mass flux (G = 188.97, 283.45, and 377.94 kg/m2s) on pressure drops (Ap) and temperatures at the central point of the main heater surface (Twc) were experimentally studied. The results showed that, heat flux, length of the main heater surface, and mass flux were identified as the important parameters to the boiling instability process. The boiling incipience (TBI) and critical heat flux (CHF) were early induced for the lower mass flux or the main heater surface with longer length. With heat flux increasing, the pressure drops were linearly and slightly decreased in the single liquid region but increased sharply in the two phase flow region, in which the flow boiling instabilities with apparent amplitude and long period were more easily triggered at high heat flux. Moreover, the system pressure was increased with the increase of the heat flux.

Use of high-boiling point organic solvents for pulping oil palm empty fruit bunches.

PubMed

Rodríguez, Alejandro; Serrano, Luis; Moral, Ana; Pérez, Antonio; Jiménez, Luis

2008-04-01

Oil palm empty fruit bunches were used as an alternative raw material to obtain cellulosic pulp. Pulping was done by using high-boiling point organic solvents of decreased polluting power relative to classical (Kraft, sulphite) solvents but affording operation at similar pressure levels. The holocellulose, alpha-cellulose and lignin contents of oil palm empty fruit bunches (viz. 66.97%, 47.91% and 24.45%, respectively) are similar to those of some woody raw materials such as pine and eucalyptus, and various non-wood materials including olive tree prunings, wheat straw and sunflower stalks. Pulping tests were conducted by using ethyleneglycol, diethyleneglycol, ethanolamine and diethanolamine under two different sets of operating conditions, namely: (a) a 70% solvent concentration, 170 degrees C and 90 min; and (b) 80% solvent, 180 degrees C and 150 min. The solid/liquid ratio was six in both cases. The amine solvents were found to provide pulp with better properties than did the glycol solvents. Ethanolamine pulp exhibited the best viscosity and drainage index (viz. 636 mL/g and 17 degrees SR, respectively), and paper made from it the best breaking length (1709 m), stretch (1.95%), burst index (0.98 kN/g) and tear index (0.33 mNm(2)/g). Operating costs can be reduced by using milder conditions, which provide similar results. In any case, the amines are to be preferred to the glycols as solvents for this purpose.

Reorientational dynamics in molecular liquids as revealed by dynamic light scattering: from boiling point to glass transition temperature.

PubMed

Schmidtke, B; Petzold, N; Kahlau, R; Rössler, E A

2013-08-28

We determine the reorientational correlation time τ of a series of molecular liquids by performing depolarized light scattering experiments (double monochromator, Fabry-Perot interferometry, and photon correlation spectroscopy). Correlation times in the range 10(-12) s-100 s are compiled, i.e., the full temperature interval between the boiling point and the glass transition temperature T(g) is covered. We focus on low-T(g) liquids for which the high-temperature limit τ ≅ 10(-12) s is easily accessed by standard spectroscopic equipment (up to 440 K). Regarding the temperature dependence three interpolation formulae of τ(T) with three parameters each are tested: (i) Vogel-Fulcher-Tammann equation, (ii) the approach recently discussed by Mauro et al. [Proc. Natl. Acad. Sci. U.S.A. 106, 19780 (2009)], and (iii) our approach decomposing the activation energy E(T) in a constant high temperature value E∞ and a "cooperative part" E(coop)(T) depending exponentially on temperature [Schmidtke et al., Phys. Rev. E 86, 041507 (2012)]. On the basis of the present data, approaches (i) and (ii) are insufficient as they do not provide the correct crossover to the high-temperature Arrhenius law clearly identified in the experimental data while approach (iii) reproduces the salient features of τ(T). It allows to discuss the temperature dependence of the liquid's dynamics in terms of a E(coop)(T)/E∞ vs. T/E∞ plot and suggests that E∞ controls the energy scale of the glass transition phenomenon.

Environmental assessment of a watertube boiler firing a coal-water slurry. Volume 1. Technical results. Final report, January 1984-March 1985

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeRosier, R.; Waterland, L.R.

1986-02-01

The report describes results from field testing a watertube industrial boiler firing a coal/water slurry (CWS) containing about 60% coal. Emission measurements included continuous monitoring of flue-gas emissions; source assessment sampling system (SASS) sampling of the flue-gas, with subsequent analysis of samples to obtain total flue-gas organics in two boiling point ranges, compound category information within these ranges, specific quantitation of the semivolatile organic priority pollutants, and flue-gas concentrations of 73 trace elements: EPA Methods 5/8 sampling for particulate, SO/sub 2/, and SO/sub 3/ emissions; and grab sampling of fuel and ash for inorganic composition. NOx, SO/sub 2/, CO, andmore » TUHC emissions were in the 230-310, 880-960, 170-200, and 1-3 ppm ranges (corrected to 3% 02), respectively, over the two tests performed. Particulate levels at the boiler outlet (upstream of the unit's baghouse) were 7.3 g/dscm in the comprehensive test. Coarse particulate (>3 micrometers) predominated. Total organic emissions were almost 50 mg/dscm, with about 70% of the organic matter in the nonvolatile (>300 C) boiling point range. The bottom ash organic content was 8 mg/g, 80% of which was in the nonvolatile range. Of the PAHs, only naphthalene was detected in the flue gas particulate, with emission levels of 8.6 micrograms/dscm. Several PAHs were found in the bottom ash.« less

Booster propulsion/vehicle impact study, 2

NASA Technical Reports Server (NTRS)

Johnson, P.; Satterthwaite, S.; Carson, C.; Schnackel, J.

1988-01-01

This is the final report in a study examining the impact of launch vehicles for various boost propulsion design options. These options included: differing boost phase engines using different combinations of fuels and coolants to include RP-1, methane, propane (subcooled and normal boiling point), and hydrogen; variable and high mixture ratio hydrogen engines; translating nozzles on boost phase engines; and cross feeding propellants from the booster to second stage. Vehicles examined included a fully reusable two stage cargo vehicle and a single stage to orbit vehicle. The use of subcooled propane as a fuel generated vehicles with the lowest total vehicle dry mass. Engines with hydrogen cooling generated only slight mass reductions from the reference, all-hydrogen vehicle. Cross feeding propellants generated the most significant mass reductions from the reference two stage vehicle. The use of high mixture ratio or variable mixture ratio hydrogen engines in the boost phase of flight resulted in vehicles with total dry mass 20 percent greater than the reference hydrogen vehicle. Translating nozzles for boost phase engines generated a heavier vehicle. Also examined were the design impacts on the vehicle and ground support subsystems when subcooled propane is used as a fuel. The most significant cost difference between facilities to handle normal boiling point versus subcooled propane is 5 million dollars. Vehicle cost differences were negligible. A significant technical challenge exists for properly conditioning the vehicle propellant on the ground and in flight when subcooled propane is used as fuel.

Targeted Nanoparticle Thermometry: A Method to Measure Local Temperature at the Nanoscale Point Where Water Vapor Nucleation Occurs.

PubMed

Alaulamie, Arwa A; Baral, Susil; Johnson, Samuel C; Richardson, Hugh H

2017-01-01

An optical nanothermometer technique based on laser trapping, moving and targeted attaching an erbium oxide nanoparticle cluster is developed to measure the local temperature. The authors apply this new nanoscale temperature measuring technique (limited by the size of the nanoparticles) to measure the temperature of vapor nucleation in water. Vapor nucleation is observed after superheating water above the boiling point for degassed and nondegassed water. The average nucleation temperature for water without gas is 560 K but this temperature is lowered by 100 K when gas is introduced into the water. The authors are able to measure the temperature inside the bubble during bubble formation and find that the temperature inside the bubble spikes to over 1000 K because the heat source (optically-heated nanorods) is no longer connected to liquid water and heat dissipation is greatly reduced. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Absolute Determination of High DC Voltages by Means of Frequency Measurement

NASA Astrophysics Data System (ADS)

Peier, Dirk; Schulz, Bernd

1983-01-01

A novel absolute measuring procedure is presented for the definition of fixed points of the voltage in the 100 kV range. The method is based on transit time measurements with accelerated electrons. By utilizing the selective interaction of a monoenergetic electron beam with the electromagnetic field of a special cavity resonator, the voltage is referred to fundamental constants and the base unit second. Possible balance voltages are indicated by a current detector. Experimental investigations are carried out with resonators in the normal conducting range. With a copper resonator operating at the temperature of boiling nitrogen (77 K), the relative uncertainty of the voltage points is estimated to be +/- 4 × 10-4. The technically realizable uncertainty can be reduced to +/- 1 × 10-5 by the proposed application of a superconducting niobium resonator. Thus this measuring device becomes suitable as a primary standard for the high-voltage range.

What can nuclear collisions teach us about the boiling of water or the formation of multi-star systems

NASA Astrophysics Data System (ADS)

Gross, D. H. E.

2001-11-01

Phase transitions in nuclei, small atomic clusters and self-gravitating systems demand the extension of thermo-statistics to "Small" systems. The main obstacle is the thermodynamic limit. It is shown how the original definition of the entropy by Boltzmann as the volume of the energy-manifold of the N-body phase space allows a geometrical definition of the entropy as function of the conserved quantities. Without invoking the thermodynamic limit the whole "zoo" of phase transitions and critical points/lines can be unambiguously defined. The relation to the Yang-Lee singularities of the grand-canonical partition sum is pointed out. It is shown that just phase transitions in non-extensive systems give the complete set of characteristic parameters of the transition including the surface tension. Nuclear heavy-ion collisions are an experimental playground to explore this extension of thermo-statistics

Arab light crude study focuses on kinematic viscosity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beg, S.A.; Al-Mutawa, A.H.; Amin, M.B.

1989-02-01

Arab light crude oil has been characterized in terms of API gravity, total sulfur content, Reid vapor pressure, ash content, heating value, salt content, viscosity SUS, vanadium content as V/sub 2/O/sub 5/, pour point and analyses of various metals. The crude oil was fractionated into six true boiling point (TBP) fractions (IBP-95/sup 0/C, 95-205/sup 0/C, 205-260/sup 0/C, 260-345/sup 0/C, 345-455/sup 0/C and 455/sup 0/C+). These fractions were characterized in terms of API gravity, total sulfur, H/sub 2/S, mercaptan contents, molecular weight, elemental analyses for total carbon, hydrogen and nitrogen, and analyses of various metals. The kinematic viscosity data have beenmore » obtained for 95/sup 0/C+ TBP fractions for a wide range of temperature up to 200/sup 0/C.« less

Characterization of Arab medium crude fractions with emphasis on kinematic viscosity - temperature behavior

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beg, S.A.; Amin, M.B.; Hussain, I.

1986-01-01

Characterization of Arab medium Crude Oil, has been carried out in terms of API gravity, debutanized crude gravity, total sulfur content, Reid vapour pressure ash content, heating value, salt content, viscosity SUS, vanadium content as V/sub 2/O/sub 5/, pour point and analysis of various metals. Further, six true boiling point (TBP) fractions (IBP-95/sup 0/C, 95-205/sup 0/C, 205-260/sup 0/C, 260-345/sup 0/C, 345-455/sup 0/C and 455/sup 0/C+) of this crude were characterized in terms of API gravity, total sulfur contents H/sub 2/S content, mercaptons content, molecular weight, elemental analyses for total carbon, hydrogen and nitrogen, analyses of various metals and paraffin, aromaticmore » and naphthene contents of lighter fractions. The kinematic viscosity-temperature data have been obtained for 95/sup 0/C+ TBP fractions for a wide range of temperatures.« less

Comparative study of cryogen spray cooling with R-134a and R-404a: implications for laser treatment of dark human skin

NASA Astrophysics Data System (ADS)

Dai, Tianhong; Yaseen, Mohammad A.; Diagaradjane, Parmeswaran; Chang, David W.; Anvari, Bahman

2006-07-01

Cutaneous laser treatment in dark skin patients is challenging due to significant light absorption by the melanin at the basal layer of epidermis, which can result in irreversible nonspecific thermal injury to the epidermis. Cryogen spray cooling (CSC) with R-134a (boiling point ≈ -26.2°C at 1 atm), which is currently used during cutaneous laser treatment, has shown poor efficacy in protecting dark human skin. We investigated the potential of CSC with R-404a (boiling point ≈ -46.5°C at 1 atm), which has a lower boiling point than R-134a, for improved therapeutic outcome in dark human skin at three levels: in vitro (epoxy resin skin phantom), ex vivo (normal dark human skin sample), and in vivo (skin of the rabbit external ear). The skin phantom was used to acquire the surface and internal temperature profiles in response to CSC with R-134a or R-404a at various spurt durations, based upon which CSC-induced heat removal from the skin phantom was estimated using an algorithm that solved a one-dimensional inverse heat conduction problem. CSC with R-404a increased the temperature reductions within the phantom and subsequently the amount of heat removal from the phantom in comparison to that with R-134a. Normal ex vivo Fitzpatrick types V-VI human skin samples were used to investigate the thermal response of dark human skin epidermis to CSC (R-134a or R-404a) at various spurt durations in conjunction with 595-nm pulsed dye laser irradiation at various radiant exposures. Cryogen R-404a increased the threshold radiant exposures for irreversible thermal injury to the epidermis in dark pigmentation skin. No obvious CSC-induced morphological changes to human skin was observed when sprayed with R404-a spurts using durations up to 300 ms. In vivo rabbit ear vasculature was used as a model of cutaneous anomalies to assess the influences of CSC (with R-134a or R-404a) on the photothermolysis of dermal blood vessels. CSC (R-134a or R-404a) with the spurt durations of 100 to 300 ms increased the most superficial depth of thermally damaged dermal blood vessel compared with the sites without CSC, implying possible nonspecific cooling of superficial dermal blood vessels by the cryogen spurts with the settings applied.

Hidden isometry of "T-duality without isometry"

NASA Astrophysics Data System (ADS)

Bouwknegt, Peter; Bugden, Mark; Klimčík, Ctirad; Wright, Kyle

2017-08-01

We study the T-dualisability criteria of Chatzistavrakidis, Deser and Jonke [3] who recently used Lie algebroid gauge theories to obtain sigma models exhibiting a "Tduality without isometry". We point out that those T-dualisability criteria are not written invariantly in [3] and depend on the choice of the algebroid framing. We then show that there always exists an isometric framing for which the Lie algebroid gauging boils down to standard Yang-Mills gauging. The "T-duality without isometry" of [3] is therefore nothing but traditional isometric non-Abelian T-duality in disguise.

Alternative Training Agents Phase 4. Large-Scale Tests

DTIC Science & Technology

1992-02-01

20 BLEND BY MOLES OF 2,2-DICHLORO-1,1,1-TRIFLUOROETHANE AND 1-CHLORO-1,1- DIFLUOROETHANE , BOTH TECHNICAL GRADES)** 1.0 SCOPE 1.1 This specification...pure 1-chloro- 1,1- difluoroethane , suitable as a fire extinguishing fluid for firefighter training and shall conform to the requirements of Table B-1...percent by moles 1-Chloro-1,l- difluoroethane 20.0 ± 1 4.4.1 percent by moles Boiling Point, degrees Celsius -10 to +28 4.4.2 at 760 mm Hg (14 to 82 ’F

Technology Assessment of Gasses Useful as Coolants in Open Cycle Joule-Thomson Cyrostat Coolers

DTIC Science & Technology

1989-09-30

t By ,1 3 T’’ i LIST OF TABLES TABLE TITLE PAGE 3-1 List of Refrigerants Not Acceptable 6-7 B.P. > -78"C at 1 Atmosphere Pressure 3-2 List of...criteria consisted of six steps as follows: 1 1. The boiling point at one atmosphere pressure must be less than - 100 degrees Centigrade, (’C...is inside the seeker head covered by a dome which is normally pressurized to one (1) atmosphere and as the gas flows to cool the detector, the gas

Liquid-Hydrogen-Cooled 450-hp Electric Motor Test Stand Being Developed

NASA Technical Reports Server (NTRS)

Kascak, Albert F.; Trudell, Jeffrey J.; Brown, Gerald V.

2005-01-01

With growing concerns about global warming, there is a need to develop pollution-free aircraft. One approach is to use hydrogen-fueled airc raft that use fuel cells or turbogenerators to produce electric power to drive the electric motors that turn the aircraft#s propulsive fan s. Hydrogen fuel would be carried as a liquid, stored at its boiling point of 20.5 K (-422.5 ?F). Conventional electric motors, however, are too heavy to use on an aircraft. We need to develop high-power, lig htweight electric motors (high-powerdensity motors).

Impact of nonabsorbing control rod tips on kinetics feedback for BWR turbine trip without bypass RETRAN-03 analyses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feltus, M.A.; Knerr, R.; Shoop, U.

1993-01-01

RETRAN-03 studies were performed for the boiling water reactor (BWR) turbine trip without bypass (TTWOB) event to investigate how the non-neutron-absorbing material on control rod tips affect scram delay timing and reactivity feedback. Scram delay, Doppler temperature, and moderator void (density) feedback were varied to assess their relative impact on kinetics behavior. Although a generic point-kinetics RETRAN-03 TTWOB model 2 was employed, actual plant information was used to develop the basic and parametric cases.

Geology and Geohydrology at CRREL, Hanover, New Hampshire: Relationship to Subsurface Contamination

DTIC Science & Technology

1992-11-01

8217 4345’ -. . . p L E G E N D --------O :------- ’ 0. .. -/ KYANITE - STAUROLITE / ~ . -*ZONE - • STAUROLITE ZONE / ,’’"’’":’:": E• GARNJET ZONE...water partition coefficient: 126 mL/g to the following equation (after Hubbert 1953) Density: 1.46 g/cm 3 Boiling point at 760 torr pressure: 87°C...Washington, D.C.: U.S. Govern-Bullein No 19.ment Printing Office. Stewart, D.P. and P. MacClintock (1969) The surfi- melt Png O.cial geology and pleistocene

Status review of PMR polyimides. [Polymerization of Monomer Reactants

NASA Technical Reports Server (NTRS)

Serafini, T. T.

1979-01-01

In the NASA developed PMR (polymerization of monomer reactants) the reinforcing fibers are impregnated with a solution containing a mixture of monomers dissolved in a low boiling point alkyl alcohol solvent, with the monomers reacting in situ at elevated temperatures to form a thermo-oxidatively stable polyimide matrix. The current status of first and second generation PMR polyimides is reviewed, considering synthesis and properties, processing, and applications. It is concluded that the PMR approach offers various significant advantages, especially superior high temperature properties and processing versatility, to fabricators and users of polyimide/fiber composites.

Assessment of correlations and models for the prediction of CHF in water subcooled flow boiling

NASA Astrophysics Data System (ADS)

Celata, G. P.; Cumo, M.; Mariani, A.

1994-01-01

The present paper provides an analysis of available correlations and models for the prediction of Critical Heat Flux (CHF) in subcooled flow boiling in the range of interest of fusion reactors thermal-hydraulic conditions, i.e. high inlet liquid subcooling and velocity and small channel diameter and length. The aim of the study was to establish the limits of validity of present predictive tools (most of them were proposed with reference to light water reactors (LWR) thermal-hydraulic studies) in the above conditions. The reference dataset represents almost all available data (1865 data points) covering wide ranges of operating conditions in the frame of present interest (0.1 less than p less than 8.4 MPa; 0.3 less than D less than 25.4 mm; 0.1 less than L less than 0.61 m; 2 less than G less than 90.0 Mg/sq m/s; 90 less than delta T(sub sub,in) less than 230 K). Among the tens of predictive tools available in literature four correlations (Levy, Westinghouse, modified-Tong and Tong-75) and three models (Weisman and Ileslamlou, Lee and Mudawar and Katto) were selected. The modified-Tong correlation and the Katto model seem to be reliable predictive tools for the calculation of the CHF in subcooled flow boiling.

Treatment of different parts of corn stover for high yield and lower polydispersity lignin extraction with high-boiling alkaline solvent.

PubMed

Yang, Mengyao; Rehman, Muhammad Saif Ur; Yan, Tingxuan; Khan, Asad Ullah; Oleskowicz-Popiel, Piotr; Xu, Xia; Cui, Ping; Xu, Jian

2018-02-01

The influence of different parts of corn stover on lignin extraction was investigated. Five kinds of lignin were isolated by the high boiling point solvent extraction from the whole corn stover and four different parts including leaf, husk, bark and pith. The optimal condition was obtained: 6.25 g/L NaOH, 140 °C, 1 h and 60% (v/v) 1,4-butanediol. The extracted lignins were then characterized. FT-IR analysis revealed that all of the lignins were typically herbaceous. The lignin extracted from husk contained more S unit. Gel permeation chromatography analysis showed that it was necessary to separate corn stover into different parts to obtain low polydispersity lignin. The SEM and FT-IR analysis proved that the lignin dissolution was related to the tightness structure presenting a positive correlation with hydrogen bond index. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lessons learned: design, start-up, and operation of cryogenic systems

NASA Astrophysics Data System (ADS)

Bell, W. M.; Bagley, R. E.; Motew, S.; Young, P.-W.

2014-11-01

Cryogenic systems involving a pumped cryogenic fluid, such as liquid nitrogen (LN2), require careful design since the cryogen is close to its boiling point and cold. At 1 atmosphere, LN2 boils at 77.4 K (-320.4 F). These systems, typically, are designed to transport the cryogen, use it for process heat removal, or for generation of gas (GN2) for process use. As the design progresses, it is important to consider all aspects of the design including, cryogen storage, pressure control and safety relief systems, thermodynamic conditions, equipment and instrument selection, materials, insulation, cooldown, pump start-up, maximum design and minimum flow rates, two phase flow conditions, heat flow, process control to meet and maintain operating conditions, piping integrity, piping loads on served equipment, warm-up, venting, and shut-down. "Cutting corners" in the design process can result in stalled start-ups, field rework, schedule hits, or operational restrictions. Some of these "lessoned learned" are described in this paper.

Subcooling for Long Duration In-Space Cryogenic Propellant Storage

NASA Technical Reports Server (NTRS)

Mustafi, Shuvo; Johnson, Wesley; Kashani, Ali; Jurns, John; Kutter, Bernard; Kirk, Daniel; Shull, Jeff

2010-01-01

Cryogenic propellants such as hydrogen and oxygen are crucial for exploration of the solar system because of their superior specific impulse capability. Future missions may require vehicles to remain in space for months, necessitating long-term storage of these cryogens. A Thermodynamic Cryogen Subcooler (TCS) can ease the challenge of cryogenic fluid storage by removing energy from the cryogenic propellant through isobaric subcooling of the cryogen below its normal boiling point prior to launch. The isobaric subcooling of the cryogenic propellant will be performed by using a cold pressurant to maintain the tank pressure while the cryogen's temperature is simultaneously reduced using the TCS. The TCS hardware will be integrated into the launch infrastructure and there will be no significant addition to the launched dry mass. Heat leaks into all cryogenic propellant tanks, despite the use of the best insulation systems. However, the large heat capacity available in the subcooled cryogenic propellants allows the energy that leaks into the tank to be absorbed until the cryogen reaches its operational thermodynamic condition. During this period of heating of the subcooled cryogen there will be minimal loss of the propellant due to venting for pressure control. This simple technique can extend the operational life of a spacecraft or an orbital cryogenic depot for months with minimal mass penalty. In fact isobaric subcooling can more than double the in-space hold time of liquid hydrogen compared to normal boiling point hydrogen. A TCS for cryogenic propellants would thus provide an enhanced level of mission flexibility. Advances in the important components of the TCS will be discussed in this paper.

Performance of an electrothermal swing adsorption system with postdesorption liquefaction for organic gas capture and recovery.

PubMed

Mallouk, Kaitlin E; Rood, Mark J

2013-07-02

The use of adsorption on activated carbon fiber cloth (ACFC) followed by electrothermal swing adsorption (ESA) and postdesorption pressure and temperature control allows organic gases with boiling points below 0 °C to be captured from air streams and recovered as liquids. This technology has the potential to be a more sustainable abatement technique when compared to thermal oxidation. In this paper, we determine the process performance and energy requirements of a gas recovery system (GRS) using ACFC-ESA for three adsorbates with relative pressures between 8.3 × 10(-5) and 3.4 × 10(-3) and boiling points as low as -26.3 °C. The GRS is able to capture > 99% of the organic gas from the feed air stream, which is comparable to destruction efficiencies for thermal oxidizers. The energy used per liquid mole recovered ranges from 920 to 52,000 kJ/mol and is a function of relative pressure of the adsorbate in the feed gas. Quantifying the performance of the bench-scale gas recovery system in terms of its ability to remove organic gases from the adsorption stream and the energy required to liquefy the recovered organic gases is a critical step in developing new technologies to allow manufacturing to occur in a more sustainable manner. To our knowledge, this is the first time an ACFC-ESA system has been used to capture, recover, and liquefy organic compounds with vapor pressures as low as 8.3 × 10(-5) and the first time such a system has been analyzed for process performance and energy consumption.

Growth and Morphology of Supercritical Fluids, a Fluid Physics Experiment Conducted on Mir, Complete

NASA Technical Reports Server (NTRS)

Wilkinson, R. Allen

2001-01-01

The Growth and Morphology of Supercritical Fluids (GMSF) is an international experiment facilitated by the NASA Glenn Research Center and under the guidance of U.S. principal investor Professor Hegseth of the University of New Orleans and three French coinvestigators: Daniel Beysens, Yves Garrabos, and Carole Chabot. The GMSF experiments were concluded in early 1999 on the Russian space station Mir. The experiments spanned the three science themes of near-critical phase separation rates, interface dynamics in near-critical boiling, and measurement of the spectrum of density fluctuation length scales very close to the critical point. The fluids used were pure CO2 or SF6. Three of the five thermostats used could adjust the sample volume with the scheduled crew time. Such a volume adjustment enabled variable sample densities around the critical density as well as pressure steps (as distinct from the usual temperature steps) applied to the sample. The French-built ALICE II facility was used for these experiments. It allows tightly thermostated (left photograph) samples (right photograph) to be controlled and viewed/measured. Its diagnostics include interferometry, shadowgraph, high-speed pressure measurements, and microscopy. Data were logged on DAT tapes, and PCMCIA cards and were returned to Earth only after the mission was over. The ground-breaking near critical boiling experiment has yielded the most results with a paper published in Physical Review Letters (ref. 1). The boiling work also received press in Science Magazine (ref. 2). This work showed that, in very compressible near-critical two-phase pure fluids, a vapor bubble was induced to temporarily overheat during a rapid heating of the sample wall. The temperature rise in the vapor was 23-percent higher than the rise in the driving container wall. The effect is due to adiabatic compression of the vapor bubble by the rapid expansion of fluid near the boundary during heatup. Thermal diffusivity is low near the critical point, so getting heat out of the compressed bubble is observably slow. This gives the appearance of a backward heat flow, or heat flow from a cold surface to a warm fluid.

A computer simulation study of the temperature dependence of the hydrophobic hydration

NASA Astrophysics Data System (ADS)

Guillot, B.; Guissani, Y.

1993-11-01

The test particle method is used to evaluate by molecular dynamics calculations the solubility of rare gases and of methane in water between the freezing point and the critical point. A quantitative agreement is obtained between solubility data and simulation results when the simulated water is modeled by the extended simple point charge model (SPCE). From a thermodynamical point of view, it is shown that the hierarchy of rare gases solubilities in water is governed by the solute-water interaction energy while an entropic term of cavity formation is found to be responsible for the peculiar temperature dependence of the solubility along the coexistence curve, and more precisely, of the solubility minimum exhibited by all the investigated solutes. Near the water critical point, the asymptotic behaviors of the Henry's constant and of the vapor-liquid partition coefficient, respectively, as deduced from the simulation data follow with a good accuracy the critical laws recently proposed in the literature for these quantities. Moreover, the calculated partial molar volume of the solute shows a steep increase above 473 K and becomes proportional to the isothermal compressibility of the pure solvent in the vicinity of the critical point as it is observed experimentally. From a microscopic point of view, the evaluation of the solute-solvent pair distribution functions permits to establish a relationship between the increase of the solubility with the decrease of the temperature in cold water on the one hand, and the formation of cages of the clathrate-type around the solute on the other hand. Nevertheless, as soon as the boiling point of water is reached the computer simulation shows that the water molecules of the first hydration shell are no longer oriented tangentially to the solute and tend to reorientate towards the bulk. At higher temperatures a deficit of water molecules progressively appears around the solute, a deficit which is directly associated with an increase of the partial molar volume. Although this phenomenon could be related to what is observed in supercritical mixtures it is emphasized that no long range critical fluctuation is present in the simulated sample.

Reduced Boil-Off System Sizing

NASA Technical Reports Server (NTRS)

Guzik, Monica C.; Plachta, David W.; Feller, Jeffrey R.

2015-01-01

NASA is currently developing cryogenic propellant storage and transfer systems for future space exploration and scientific discovery missions by addressing the need to raise the technology readiness level of cryogenic fluid management technologies. Cryogenic propellants are baselined in many propulsion systems due to their inherently high specific impulse; however, their low boiling points can cause substantial boil-off losses over time. Recent efforts such as the Reduced Boil-off Testing and the Active Thermal Control Scaling Study provide important information on the benefit of an active cooling system applied to LH2 propellant storage. Findings show that zero-boil off technologies can reduce overall mass in LH2 storage systems when low Earth orbit loiter periods extend beyond two months. A significant part of this mass reduction is realized by integrating two stages of cooling: a 20 K stage to intercept heat at the tank surface, and a 90 K stage to reduce the heat entering the less efficient 20 K stage. A missing element in previous studies, which is addressed in this paper, is the development of a direct method for sizing the 90 K cooling stage. Such a method requires calculation of the heat entering both the 90 K and 20 K stages as compared to the overall system masses, and is reliant upon the temperature distribution, performance, and unique design characteristics of the system in question. By utilizing the known conductance of a system without active thermal control, the heat being intercepted by a 90 K stage can be calculated to find the resultant lift and mass of each active thermal control stage. Integral to this is the thermal conductance of the cooling straps and the broad area cooling shield, key parts of the 90 K stage. Additionally, a trade study is performed to show the ability of the 90 K cooling stage to reduce the lift on the 20 K cryocooler stage, which is considerably less developed and efficient than 90 K cryocoolers.

Stability analysis of BWR nuclear-coupled thermal-hyraulics using a simple model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karve, A.A.; Rizwan-uddin; Dorning, J.J.

1995-09-01

A simple mathematical model is developed to describe the dynamics of the nuclear-coupled thermal-hydraulics in a boiling water reactor (BWR) core. The model, which incorporates the essential features of neutron kinetics, and single-phase and two-phase thermal-hydraulics, leads to simple dynamical system comprised of a set of nonlinear ordinary differential equations (ODEs). The stability boundary is determined and plotted in the inlet-subcooling-number (enthalpy)/external-reactivity operating parameter plane. The eigenvalues of the Jacobian matrix of the dynamical system also are calculated at various steady-states (fixed points); the results are consistent with those of the direct stability analysis and indicate that a Hopf bifurcationmore » occurs as the stability boundary in the operating parameter plane is crossed. Numerical simulations of the time-dependent, nonlinear ODEs are carried out for selected points in the operating parameter plane to obtain the actual damped and growing oscillations in the neutron number density, the channel inlet flow velocity, and the other phase variables. These indicate that the Hopf bifurcation is subcritical, hence, density wave oscillations with growing amplitude could result from a finite perturbation of the system even where the steady-state is stable. The power-flow map, frequently used by reactor operators during start-up and shut-down operation of a BWR, is mapped to the inlet-subcooling-number/neutron-density (operating-parameter/phase-variable) plane, and then related to the stability boundaries for different fixed inlet velocities corresponding to selected points on the flow-control line. The stability boundaries for different fixed inlet subcooling numbers corresponding to those selected points, are plotted in the neutron-density/inlet-velocity phase variable plane and then the points on the flow-control line are related to their respective stability boundaries in this plane.« less

Propulsion and Power Rapid Response R&D Support. Delivery Order 0013: Micro Gas Chromatography Tradeoff Study

DTIC Science & Technology

2003-11-01

klick on File TL-03- uGC -Model.xls Model 2. Determination of Peak Capacity for 0.1 < k’ < 5. This tool was intended to help with the determination of peak...dependent on the agreed k’ range, i.e. the associated boiling point range. Double-klick on File TL-03- uGC -Model.xls Model 3. Estimation of the Fraction...available today on the market .6 Figure 6 is a 2 second GC chromatogram of 7 test compounds using the 100 micron square capillary column (see Figure 4

Superconductivity achieved at over liquid nitrogen temperature by (mixed rare earths)-Ba-Cu oxides

NASA Astrophysics Data System (ADS)

Kishio, Kohji; Kuwahara, Kazuyuki; Kitazawa, Koichi; Fueki, Kazuo; Nakamura, Osamu

1987-05-01

Superconducting oxides were fabricated by reaction of powders of BaCO3, CuO and mixed rare earth (RE) carbonates at compositions expressed as (RE)1Ba2Cu3O(9-y). Two types of incompletely separated raw materials of mixed rare earths, namely, heavy rare earths (HRE) and medium rare earths (MRE), were examined. The zero-resistivity critical temperatures were observed at 92.5 K for the (HRE)-Ba-Cu-O and 85.0 K for the (MRE)-Ba-Cu-O systems, respectively, both of which were well above the boiling point of liquid nitrogen.

Liquid-vapor phase equilibria and the thermodynamic properties of 2-methylpropanol- n-alkyl propanoate solutions

NASA Astrophysics Data System (ADS)

Suntsov, Yu. K.; Goryunov, V. A.; Chuikov, A. M.; Meshcheryakov, A. V.

2016-08-01

The boiling points of solutions of five binary systems are measured via ebulliometry in the pressure range of 2.05-103.3 kPa. Equilibrium vapor phase compositions, the values of the excess Gibbs energies, enthalpies, and entropies of solution of these systems are calculated. Patterns in the changes of phase equilibria and thermodynamic properties of solutions are established, depending on the compositions and temperatures of the systems. Liquid-vapor equilibria in the systems are described using the equations of Wilson and the NRTL (Non-Random Two-Liquid Model).

Two-stage coal liquefaction process

DOEpatents

Skinner, Ronald W.; Tao, John C.; Znaimer, Samuel

1985-01-01

An improved SRC-I two-stage coal liquefaction process which improves the product slate is provided. Substantially all of the net yield of 650.degree.-850.degree. F. heavy distillate from the LC-Finer is combined with the SRC process solvent, substantially all of the net 400.degree.-650.degree. F. middle distillate from the SRC section is combined with the hydrocracker solvent in the LC-Finer, and the initial boiling point of the SRC process solvent is increased sufficiently high to produce a net yield of 650.degree.-850.degree. F. heavy distillate of zero for the two-stage liquefaction process.

Apparatus for pumping liquids at or below the boiling point

DOEpatents

Bingham, Dennis N.

2002-01-01

A pump comprises a housing having an inlet and an outlet. An impeller assembly mounted for rotation within the housing includes a first impeller piece having a first mating surface thereon and a second impeller piece having a second mating surface therein. The second mating surface of the second impeller piece includes at least one groove therein so that at least one flow channel is defined between the groove and the first mating surface of the first impeller piece. A drive system operatively associated with the impeller assembly rotates the impeller assembly within the housing.

High Tc superconducting films from metallo-organic precursors

NASA Astrophysics Data System (ADS)

Davison, W. W.; Shyu, S. G.; Buchanan, R. C.

High Tc superconducting films of heavy metal soaps (derived from carboxylic acid precursors) have been prepared on Si and other substrates. The precursors were synthesized and mixed in appropriate molar ratios to form the high Tc compound YBa2Cu3O(7-x), using a high boiling point common solvent base. The precursor solution was deposited by a spin casting technique on the substrates. Film thicknesses of 0.1-1.0 micron were achieved after heat treatment at 550-850 C at not longer than 4 hours. Films were analyzed as to orientation, appropriate phase, interfacial reaction, and superconducting properties.

Method for loading resin beds

DOEpatents

Notz, Karl J.; Rainey, Robert H.; Greene, Charles W.; Shockley, William E.

1978-01-01

An improved method of preparing nuclear reactor fuel by carbonizing a uranium loaded cation exchange resin provided by contacting a H.sup.+ loaded resin with a uranyl nitrate solution deficient in nitrate, comprises providing the nitrate deficient solution by a method comprising the steps of reacting in a reaction zone maintained between about 145.degree.-200.degree. C, a first aqueous component comprising a uranyl nitrate solution having a boiling point of at least 145.degree. C with a second aqueous component to provide a gaseous phase containing HNO.sub.3 and a reaction product comprising an aqueous uranyl nitrate solution deficient in nitrate.

Melt-Vapor Phase Diagram of the Te-S System

NASA Astrophysics Data System (ADS)

Volodin, V. N.; Trebukhov, S. A.; Kenzhaliyev, B. K.; Nitsenko, A. V.; Burabaeva, N. M.

2018-03-01

The values of partial pressure of saturated vapor of the constituents of the Te-S system are determined from boiling points. The boundaries of the melt-vapor phase transition at atmospheric pressure and in vacuum of 2000 and 100 Pa are calculated on the basis of partial pressures. A phase diagram that includes vapor-liquid equilibrium fields whose boundaries allow us to assess the behavior of elements upon distillation fractioning is plotted. It is established that the separation of elements is possible at the first evaporation-condensation cycle. Complications can be caused by crystallization of a sulfur solid solution in tellurium.

Sintering Kinetics of Inkjet Printed Conductive Silver Lines on Insulating Plastic Substrate

DOE PAGES

Zhou, Wenchao; List, III, Frederick Alyious; Duty, Chad E; ...

2015-01-24

This paper focuses on sintering kinetics of inkjet printed lines containing silver nanoparticles deposited on a plastic substrate. Upon heat treatment, the change of resistance in the printed lines was measured as a function of time and sintering temperatures from 150 to 200 C. A critical temperature was observed for the sintering process, beyond which there was no further reduction in resistance. Analysis shows the critical temperature correlates to the boiling point of the solvent, which is attributed to a liquid-mediated sintering mechanism. It is demonstrated that the sintering process shuts down after the solvent has completely evaporated.

Disinfection of woollen blankets in steam at subatmospheric pressure

PubMed Central

Alder, V. G.; Gillespie, W. A.

1961-01-01

Blankets may be disinfected in steam at subatmospheric pressures by temperatures below boiling point inside a suitably adapted autoclave chamber. The chamber and its contents are thoroughly evacuated of air so as to allow rapid heat penetration, and steam is admitted to a pressure of 10 in. Hg below atmospheric pressure, which corresponds to a temperature of 89°C. Woollen blankets treated 50 times by this process were undamaged. Vegetative organisms were destroyed but not spores. The method is suitable for large-scale disinfection of blankets and for disinfecting various other articles which would be damaged at higher temperatures. PMID:13860203

A Comparison of Methods for Computing the Residual Resistivity Ratio of High-Purity Niobium

PubMed Central

Splett, J. D.; Vecchia, D. F.; Goodrich, L. F.

2011-01-01

We compare methods for estimating the residual resistivity ratio (RRR) of high-purity niobium and investigate the effects of using different functional models. RRR is typically defined as the ratio of the electrical resistances measured at 273 K (the ice point) and 4.2 K (the boiling point of helium at standard atmospheric pressure). However, pure niobium is superconducting below about 9.3 K, so the low-temperature resistance is defined as the normal-state (i.e., non-superconducting state) resistance extrapolated to 4.2 K and zero magnetic field. Thus, the estimated value of RRR depends significantly on the model used for extrapolation. We examine three models for extrapolation based on temperature versus resistance, two models for extrapolation based on magnetic field versus resistance, and a new model based on the Kohler relationship that can be applied to combined temperature and field data. We also investigate the possibility of re-defining RRR so that the quantity is not dependent on extrapolation. PMID:26989580

High performance, high density hydrocarbon fuels

NASA Technical Reports Server (NTRS)

Frankenfeld, J. W.; Hastings, T. W.; Lieberman, M.; Taylor, W. F.

1978-01-01

The fuels were selected from 77 original candidates on the basis of estimated merit index and cost effectiveness. The ten candidates consisted of 3 pure compounds, 4 chemical plant streams and 3 refinery streams. Critical physical and chemical properties of the candidate fuels were measured including heat of combustion, density, and viscosity as a function of temperature, freezing points, vapor pressure, boiling point, thermal stability. The best all around candidate was found to be a chemical plant olefin stream rich in dicyclopentadiene. This material has a high merit index and is available at low cost. Possible problem areas were identified as low temperature flow properties and thermal stability. An economic analysis was carried out to determine the production costs of top candidates. The chemical plant and refinery streams were all less than 44 cent/kg while the pure compounds were greater than 44 cent/kg. A literature survey was conducted on the state of the art of advanced hydrocarbon fuel technology as applied to high energy propellents. Several areas for additional research were identified.

Experiments with the low melting indium-bismuth alloy system

NASA Technical Reports Server (NTRS)

Krepski, Richard P.

1992-01-01

The following is a laboratory experiment designed to create an interest in and to further understanding of materials science. The primary audience for this material is the junior high school or middle school science student having no previous familiarity with the material, other than some knowledge of temperature and the concepts of atoms, elements, compounds, and chemical reactions. The objective of the experiment is to investigate the indium-bismuth alloy system. Near the eutectic composition, the liquidus is well below the boiling point of water, allowing simple, minimal hazard casting experiments. Such phenomena as metal oxidation, formation of intermetallic compound crystals, and an unusual volume increase during solidification could all be directly observed. A key concept for students to absorb is that properties of an alloy (melting point, mechanical behavior) may not correlate with simple interpolation of properties of the pure components. Discussion of other low melting metals and alloys leads to consideration of environmental and toxicity issues, as well as providing some historical context. Wetting behavior can also be explored.

Latest developments in cryogenic safety

NASA Astrophysics Data System (ADS)

Webster, T. J.

1983-03-01

The Cryogenic Safety Manual, sponsored by the British Cryogenics Council, was published over 10 years ago. A new updated version is now available. Some general aspects of cryogenic safety are highlighted, and attention is drawn to some of the more unusual hazardous situations. An awareness of the physical properties of the cryogenic fluids being dealt with is important in directing attention to hazardous situations which may arise. Because of this, the more important properties of the cryogenic fluids are given, such as molecular weight, boiling point and freezing point. From these properties, hazardous situations can be deduced. There are hidden dangers that are not always easy to spot. Some of the unexpected hazards, most of which have led to deaths, are: asphyxiation (anoxia), frost bites and hypothermia, explosions, and combustion. The aim of this publication is to help bring about increased safety in the production and use of cryogenic products through a deeper appreciation of the scientific, technological and administrative steps which must be made if accidents, some fatal, are to be voided in the future.

Latest developments in cryogenic safety

NASA Technical Reports Server (NTRS)

Webster, T. J.

1983-01-01

The Cryogenic Safety Manual, sponsored by the British Cryogenics Council, was published over 10 years ago. A new updated version is now available. Some general aspects of cryogenic safety are highlighted, and attention is drawn to some of the more unusual hazardous situations. An awareness of the physical properties of the cryogenic fluids being dealt with is important in directing attention to hazardous situations which may arise. Because of this, the more important properties of the cryogenic fluids are given, such as molecular weight, boiling point and freezing point. From these properties, hazardous situations can be deduced. There are hidden dangers that are not always easy to spot. Some of the unexpected hazards, most of which have led to deaths, are: asphyxiation (anoxia), frost bites and hypothermia, explosions, and combustion. The aim of this publication is to help bring about increased safety in the production and use of cryogenic products through a deeper appreciation of the scientific, technological and administrative steps which must be made if accidents, some fatal, are to be voided in the future.

Exhaust emissions from light- and heavy-duty vehicles: chemical composition, impact of exhaust after treatment, and fuel parameters.

PubMed Central

Westerholm, R; Egebäck, K E

1994-01-01

This paper presents results from the characterization of vehicle exhaust that were obtained primarily within the Swedish Urban Air Project, "Tätortsprojektet." Exhaust emissions from both gasoline- and diesel-fueled vehicles have been investigated with respect to regulated pollutants (carbon monoxide [CO], hydrocarbon [HC], nitrogen oxides [NOx], and particulate), unregulated pollutants, and in bioassay tests (Ames test, TCDD receptor affinity tests). Unregulated pollutants present in both the particle- and the semi-volatile phases were characterized. Special interest was focused on the impact of fuel composition on heavy-duty diesel vehicle emissions. It was confirmed that there exists a quantifiable relationship between diesel-fuel variables of the fuel blends, the chemical composition of the emissions, and their biological effects. According to the results from the multivariate analysis, the most important fuel parameters are: polycyclic aromatic hydrocarbons (PAH) content, 90% distillation point, final boiling point, specific heat, aromatic content, density, and sulfur content. PMID:7529699

The Web-based Module of Changes in Objects

NASA Astrophysics Data System (ADS)

Triayomi, R.

2017-09-01

To understand the changes of substances contained in such a kind of substance and substance characteristics then need a deep study of the concept. In this concept is expected to understand the changes of objects such as substance type and substance characteristics. Types of substances and characteristics of substances through physical changes and chemical changes and means of separation consisting of two or more substances. The principle of separation of the mixture is based on differences in physical properties of its constituents, such as substances, particle size, melting point, boiling point, magnetic properties, solubility, and so forth. This study aims to produce a web-based module of changes in objects that are valid, practical, and have effectiveness of student learning outcomes and activities on natural science learning. The experiment was conducted on 30 children in South Sumatera. The case of the development of the learning module of change of the object is influenced by the child’s understanding of the concept. Expected to be adapted by world teachers.

Thermodynamic parameters of phase transitions of perfluoro-N-(4-methylcyclohexyl)piperidine

NASA Astrophysics Data System (ADS)

Druzhinina, A. I.; Efimova, A. A.; Varushchenko, R. M.; Chelovskaya, N. V.

2007-12-01

The heat capacity of perfluoro-N-(4-methylcyclohexyl)piperidine (PMCP) was measured by low-temperature adiabatic calorimetry. The purity of the substance ( N 1 = 99.66 mol %), triple point temperature ( T tp = 293.26 K), and enthalpy of fusion (Δfus H {m/°} = 8.32 kJ/mol) were determined. The enthalpy of vaporization was measured by calorimetry at 298.15 K (Δvap H {m/°}(298.15 K) = 56.56 kJ/mol). The temperature dependence of the saturated vapor pressure of PMCP over the pressure range 6.2-101.6 kPa was determined by comparative ebulliometry. The normal boiling point ( T n.b. = 460.74 K), ehthalpies of vaporization (at various temperatures), and critical parameters of PMCP were calculated. The calculated and experimental values of Δvap H {m/°}(298.15 K) agree to within measurement errors, which proves the reliability of these values and pT parameters used in calculations.

Sliding bubbles on a hot horizontal wire in a subcooled bath

NASA Astrophysics Data System (ADS)

Duchesne, Alexis; Dubois, Charles; Caps, Hervé

2015-11-01

When a wire is heated up to the boiling point in a liquid bath some bubbles will nucleate on the wire surface. Traditional nucleate boiling theory predicts that bubbles generate from active nucleate site, grow up and depart from the heating surface due to buoyancy and inertia. However, an alternative scenario is presented in the literature for a subcooled bath: bubbles slide along the horizontal wire before departing. New experiments were performed by using a constantan wire and different liquids, varying the injected power. Silicone oil, water and even liquid nitrogen were tested in order to vary wetting conditions, liquid viscosities and surface tensions. We explored the influence of the wire diameter and of the subcooled bath temperature. We observed, of course, sliding motion, but also a wide range of behaviors from bubbles clustering to film boiling. We noticed that bubbles could change moving sense, especially when encountering with another bubble. The bubble speed is carefully measured and can reach more than 100 mm/s for a millimetric bubble. We investigated the dependence of the speed on the different parameters and found that this speed is, for a given configuration, quite independent of the injected power. We understand these phenomena in terms of Marangoni effects. This project has been financially supported by ARC SuperCool contract of the University of Liège.

Evaporation of oil-water emulsion drops when heated at high temperature

NASA Astrophysics Data System (ADS)

Strizhak, P. A.; Piskunov, M. V.; Kuznetsov, G. V.; Voytkov, I. S.

2017-10-01

An experimental study on conditions and main characteristics for high-temperature (more than 700 K) evaporation of oil-water drops is presented. The high-temperature water purification from impurities can be the main practical application of research results. Thus, the heating of drops is implemented by the two typical schemes: on a massive substrate (the heating conditions are similar to those achieved in a heating chamber) and in a flow of the heated air. In the latter case, the heating conditions correspond to those attained while moving water drops with impurities in a counter high-temperature gaseous flow in the process of water purification. Evaporation time as function of heating temperature is presented. The influence of oil product concentration in an emulsion drop on evaporation characteristics is discussed. The conditions for intensive flash boiling of an emulsion drop and its explosive breakup with formation of the fine droplets cloud are pointed out. Heat fluxes required for intensive flash boiling and explosive breakup of a drop with further formation of the fine aerosol are determined in the boundary layer of a drop. The fundamental differences between flash boiling and explosive breakup of an emulsion drop when heated on a substrate and in a flow of the heated air are described. The main prospects for the development of the high-temperature water purification technology are detailed taking into account the fast emulsion drop breakup investigated in the paper.

Modeling the dynamics of a phreatic eruption based on a tilt observation: Barrier breakage leading to the 2014 eruption of Mount Ontake, Japan

NASA Astrophysics Data System (ADS)

Maeda, Yuta; Kato, Aitaro; Yamanaka, Yoshiko

2017-02-01

Although phreatic eruptions are common volcanic phenomena that sometimes result in significant disasters, their dynamics are poorly understood. In this study, we address the dynamics of the phreatic eruption of Mount Ontake, Japan, in 2014 based on analyses of a tilt change observed immediately (450 s) before the eruption onset. We conducted two sets of analysis: a waveform inversion and a modified phase-space analysis. Our waveform inversion of the tilt signal points to a vertical tensile crack at a depth of 1100 m. Our modified phase-space analysis suggests that the tilt change was at first a linear function in time that then switched to exponential growth. We constructed simple analytical models to explain these temporal functions. The linear function was explained by the boiling of underground water controlled by a constant heat supply from a greater depth. The exponential function was explained by the decompression-induced boiling of water and the upward Darcy flow of the water vapor through a permeable region of small cracks that were newly created in response to ongoing boiling. We interpret that this region was intact prior to the start of the tilt change, and thus, it has acted as a permeability barrier for the upward migration of fluids; it was a breakage of this barrier that led to the eruption.

Thermal singularity and contact line motion in pool boiling: Effects of substrate wettability.

PubMed

Taylor, M T; Qian, Tiezheng

2016-03-01

The dynamic van der Waals theory [Phys. Rev. E 75, 036304 (2007)] is employed to model the growth of a single vapor bubble in a superheated liquid on a flat homogeneous substrate. The bubble spreading dynamics in the pool boiling regime has been numerically investigated for one-component van der Waals fluids close to the critical point, with a focus on the effect of the substrate wettability on bubble growth and contact line motion. The substrate wettability is found to control the apparent contact angle and the rate of bubble growth (the rate of total evaporation), through which the contact line speed is determined. An approximate expression is derived for the contact line speed, showing good agreement with the simulation results. This demonstrates that the contact line speed is primarily governed by (1) the circular shape of interface (for slow bubble growth), (2) the constant apparent contact angle, and (3) the constant bubble growth rate. It follows that the contact line speed has a sensitive dependence on the substrate wettability via the apparent contact angle which also determines the bubble growth rate. Compared to hydrophilic surfaces, hydrophobic surfaces give rise to a thinner shape of bubble and a higher rate of total evaporation, which combine to result in a much faster contact line speed. This can be linked to the earlier formation of a vapor film and hence the onset of boiling crisis.

Visualization and flow boiling heat transfer of hydrocarbons in a horizontal tube

NASA Astrophysics Data System (ADS)

Yang, Zhuqiang; Bi, Qincheng; Guo, Yong; Liu, Zhaohui; Yan, Jianguo

2013-07-01

Visualizations of a specific hydrocarbon fuel in a horizontal tube with 2.0 mm inside diameter were investigated. The experiments were conducted at mass velocity of 213.4, 426.5 and 640.2 kg/ (m2ṡs), diabatic lengths of 140, 240 and 420 mm under the pressure from 2.0-2.7 MPa. In the sub-pressure conditions, bubbly, intermittent, stratified-wave, churn and annular flow patterns were observed. The frictional pressure drops were also measured to distinguish the patterns. The development of flow patterns and frictional pressure drop were positively related to the mass velocity and the heat flux. However, the diabatic length of the tube takes an important part in the process. The residence time of the fluid does not only affect the transition of the patterns but influence the composition of the fuel manifested by the fuel color and carbon deposit. The special observational phenomenon was obtained for the supercritical pressure fluid. The flow in the tube became fuzzier and pressure drop changed sharply near the pseudocritical point. The flow boiling heat transfer characteristics of the hydrocarbons were also discussed respectively. The curve of critical heat flux about onset of nucleate boiling was plotted with different mass velocities and diabatic tube lengths. And heat transfer characteristics of supercritical fuel were proved to be better than that in subcritical conditions.

Parametric analyses of DEMO Divertor using two dimensional transient thermal hydraulic modelling

NASA Astrophysics Data System (ADS)

Domalapally, Phani; Di Caro, Marco

2018-05-01

Among the options considered for cooling of the Plasma facing components of the DEMO reactor, water cooling is a conservative option because of its high heat removal capability. In this work a two-dimensional transient thermal hydraulic code is developed to support the design of the divertor for the projected DEMO reactor with water as a coolant. The mathematical model accounts for transient 2D heat conduction in the divertor section. Temperature-dependent properties are used for more accurate analysis. Correlations for single phase flow forced convection, partially developed subcooled nucleate boiling, fully developed subcooled nucleate boiling and film boiling are used to calculate the heat transfer coefficients on the channel side considering the swirl flow, wherein different correlations found in the literature are compared against each other. Correlation for the Critical Heat Flux is used to estimate its limit for a given flow conditions. This paper then investigates the results of the parametric analysis performed, whereby flow velocity, diameter of the coolant channel, thickness of the coolant pipe, thickness of the armor material, inlet temperature and operating pressure affect the behavior of the divertor under steady or transient heat fluxes. This code will help in understanding the basic parameterś effect on the behavior of the divertor, to achieve a better design from a thermal hydraulic point of view.

In Vitro Effects of Cooking Methods on Digestibility of Lipids and Formation of Cholesterol Oxidation Products in Pork

PubMed Central

Moon, Sung Sil

2014-01-01

This study investigated the effects of cooking methods on the digestibility of lipids and formation of cholesterol oxidation products (COPs) in pork, during in vitro human digestion. Pork patties were cooked using four different methods (oven cooking, pan frying, boiling, and microwaving), to an internal temperature of approximately 85℃. The digestibility of pork patties were then evaluated, using the in vitro human digestion model that simulated the composition (pH, minerals, surfaceactive components, and enzymes) of digestive juices in the human mouth, stomach, and small intestine. The total lipid digestibility was higher after microwave cooking, whereas pan-frying resulted in lower in vitro digestibility, compared to the other cooking methods. The microwaving method followed by in vitro digestion also showed significantly higher content of free fatty acids and thiobarbituric acid reactive substances (TBARS), compared to the other cooking methods; whereas, the pan frying and boiling methods showed the lowest. Cholesterol content was not significantly different among the cooked samples before, and after in vitro human digestion. The formation of COPs was significantly higher in the microwave-treated pork samples, compared to those cooked by the other methods, which was consistent with the trend for lipid peroxidation (TBARS). We propose that from the point of view of COPs formation and lipid oxidation, the pan-frying or boiling methods would be useful. PMID:26761168

Quality of drinking-water at source and point-of-consumption--drinking cup as a high potential recontamination risk: a field study in Bolivia.

PubMed

Rufener, Simonne; Mäusezahl, Daniel; Mosler, Hans-Joachim; Weingartner, Rolf

2010-02-01

In-house contamination of drinking-water is a persistent problem in developing countries. This study aimed at identifying critical points of contamination and determining the extent of recontamination after water treatment. In total, 81 households were visited, and 347 water samples from their current sources of water, transport vessels, treated water, and drinking vessels were analyzed. The quality of water was assessed using Escherichia coli as an indicator for faecal contamination. The concentration of E. coli increased significantly from the water source [median=0 colony-forming unit (CFU)/100 mL, interquartile range (IQR: 0-13)] to the drinking cup (median=8 CFU/100 mL; IQR: 0-550; n=81, z=-3.7, p<0.001). About two-thirds (34/52) of drinking vessels were contaminated with E. coli. Although boiling and solar disinfection of water (SODIS) improved the quality of drinking-water (median=0 CFU/100 mL; IQR: 0-0.05), recontamination at the point-of-consumption significantly reduced the quality of water in the cups (median=8, IQR: 0-500; n=45, z=-2.4, p=0.015). Home-based interventions in disinfection of water may not guarantee health benefits without complementary hygiene education due to the risk of posttreatment contamination.

Observation of surface layering in a nonmetallic liquid

NASA Astrophysics Data System (ADS)

Mo, Haiding; Evmenenko, Guennadi; Kewalramani, Sumit; Kim, Kyungil; Dutta, Pulak; Ehrlich, Steven

2006-03-01

Non-monotonic density profiles (layers) have previously been observed at the free surfaces of many metallic liquids, but not in isotropic dielectric liquids. Whether the presence of an electron gas is necessary for surface layering has been the subject of debate. Until recently, MD simulations have suggested that layering at free liquid interface may be a generic phenomenon and is not limited to the metallic liquids^1. The theories predict that if normal liquids can be cooled down to temperatures low enough, layering structure should be observed experimentally. However, this is difficult for most molecular liquids because these liquids freeze well above the temperature necessary for observing the layering structure. By studying the surface structure of liquid TEHOS (tetrakis(2-ethylhexoxy)silane), which combines relatively low freezing point and high boiling point compared to that of most molecular liquids, we have observed the evidence of layering at the free interface of liquid TEHOS using x-ray reflectivity. When cooled to T/Tc 0.25 (well above the bulk freezing point, Tc is the critical temperature of TEHOS), the surface roughness drops sharply and density oscillations appear near the surface. Lateral ordering of the surface layers is liquid-like, just as at liquid metal surfaces. 1. E. Chac'on and P. Tarazona, Phys. Rev. Lett. 91 166103-1 (2003)

Remote acoustic sensing as a safety mechanism during exposure of metal implants to alternating magnetic fields

PubMed Central

Chatzinoff, Yonatan; Szczepanski, Debby; Bing, Chenchen; Shaikh, Sumbul; Wyman, Omar; Perry, Cameron E.; Richardson, James A.; Burns, Dennis K.; Evers, Bret M.; Greenberg, David E.; Chopra, Rajiv

2018-01-01

Treatment of prosthetic joint infections often involves multiple surgeries and prolonged antibiotic administration, resulting in a significant burden to patients and the healthcare system. We are exploring a non-invasive method to eradicate biofilm on metal implants utilizing high-frequency alternating magnetic fields (AMF) which can achieve surface induction heating. Although proof-of-concept studies demonstrate the ability of AMF to eradicate biofilm in vitro, there is a legitimate safety concern related to the potential for thermal damage to surrounding tissues when considering heating implanted metal objects. The goal of this study was to explore the feasibility of detecting acoustic emissions associated with boiling at the interface between a metal implant and surrounding soft tissue as a wireless safety sensing mechanism. Acoustic emissions generated during in vitro and in vivo AMF exposures were captured with a hydrophone, and the relationship with surface temperature analyzed. The effect of AMF exposure power, surrounding media composition, implant location within the AMF transmitter, and implant geometry on acoustic detection during AMF therapy was also evaluated. Acoustic emissions were reliably identified in both tissue-mimicking phantom and mouse studies, and their onset coincided with the implant temperature reaching the boiling threshold. The viscosity of the surrounding medium did not impact the production of acoustic emissions; however, emissions were not present when the medium was oil due to the higher boiling point. Results of simulations and in vivo studies suggest that short-duration, high-power AMF exposures combined with acoustic sensing can be used to minimize the amount of thermal damage in surrounding tissues. These studies support the hypothesis that detection of boiling associated acoustic emissions at a metal/tissue interface could serve as a real-time, wireless safety indicator during AMF treatment of biofilm on metallic implants. PMID:29746579

Remote acoustic sensing as a safety mechanism during exposure of metal implants to alternating magnetic fields.

PubMed

Cheng, Bingbing; Chatzinoff, Yonatan; Szczepanski, Debby; Bing, Chenchen; Shaikh, Sumbul; Wyman, Omar; Perry, Cameron E; Richardson, James A; Burns, Dennis K; Evers, Bret M; Greenberg, David E; Chopra, Rajiv

2018-01-01

Treatment of prosthetic joint infections often involves multiple surgeries and prolonged antibiotic administration, resulting in a significant burden to patients and the healthcare system. We are exploring a non-invasive method to eradicate biofilm on metal implants utilizing high-frequency alternating magnetic fields (AMF) which can achieve surface induction heating. Although proof-of-concept studies demonstrate the ability of AMF to eradicate biofilm in vitro, there is a legitimate safety concern related to the potential for thermal damage to surrounding tissues when considering heating implanted metal objects. The goal of this study was to explore the feasibility of detecting acoustic emissions associated with boiling at the interface between a metal implant and surrounding soft tissue as a wireless safety sensing mechanism. Acoustic emissions generated during in vitro and in vivo AMF exposures were captured with a hydrophone, and the relationship with surface temperature analyzed. The effect of AMF exposure power, surrounding media composition, implant location within the AMF transmitter, and implant geometry on acoustic detection during AMF therapy was also evaluated. Acoustic emissions were reliably identified in both tissue-mimicking phantom and mouse studies, and their onset coincided with the implant temperature reaching the boiling threshold. The viscosity of the surrounding medium did not impact the production of acoustic emissions; however, emissions were not present when the medium was oil due to the higher boiling point. Results of simulations and in vivo studies suggest that short-duration, high-power AMF exposures combined with acoustic sensing can be used to minimize the amount of thermal damage in surrounding tissues. These studies support the hypothesis that detection of boiling associated acoustic emissions at a metal/tissue interface could serve as a real-time, wireless safety indicator during AMF treatment of biofilm on metallic implants.

Corresponding-states behavior of an ionic model fluid with variable dispersion interactions

NASA Astrophysics Data System (ADS)

Weiss, Volker C.

2016-06-01

Guggenheim's corresponding-states approach for simple fluids leads to a remarkably universal representation of their thermophysical properties. For more complex fluids, such as polar or ionic ones, deviations from this type of behavior are to be expected, thereby supplying us with valuable information about the thermodynamic consequences of the interaction details in fluids. Here, the gradual transition of a simple fluid to an ionic one is studied by varying the relative strength of the dispersion interactions compared to the electrostatic interactions among the charged particles. In addition to the effects on the reduced surface tension that were reported earlier [F. Leroy and V. C. Weiss, J. Chem. Phys. 134, 094703 (2011)], we address the shape of the coexistence curve and focus on properties that are related to and derived from the vapor pressure. These quantities include the enthalpy and entropy of vaporization, the boiling point, and the critical compressibility factor Zc. For all of these properties, the crossover from simple to characteristically ionic fluid is seen once the dispersive attraction drops below 20%-40% of the electrostatic attraction (as measured for two particles at contact). Below this threshold, ionic fluids display characteristically low values of Zc as well as large Guggenheim and Guldberg ratios for the reduced enthalpy of vaporization and the reduced boiling point, respectively. The coexistence curves are wider and more skewed than those for simple fluids. The results for the ionic model fluid with variable dispersion interactions improve our understanding of the behavior of real ionic fluids, such as inorganic molten salts and room temperature ionic liquids, by gauging the importance of different types of interactions for thermodynamic properties.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ratcliff, Matthew A.; Burton, Jonathan; Sindler, Petr

Several high octane number oxygenates that could be derived from biomass were blended with gasoline and examined for performance properties and their impact on knock resistance and fine particle emissions in a single cylinder direct-injection spark-ignition engine. The oxygenates included ethanol, isobutanol, anisole, 4-methylanisole, 2-phenylethanol, 2,5-dimethyl furan, and 2,4-xylenol. These were blended into a summertime blendstock for oxygenate blending at levels ranging from 10 to 50 percent by volume. The base gasoline, its blends with p-xylene and p-cymene, and high-octane racing gasoline were tested as controls. Relevant gasoline properties including research octane number (RON), motor octane number, distillation curve, andmore » vapor pressure were measured. Detailed hydrocarbon analysis was used to estimate heat of vaporization and particulate matter index (PMI). Experiments were conducted to measure knock-limited spark advance and particulate matter (PM) emissions. The results show a range of knock resistances that correlate well with RON. Molecules with relatively low boiling point and high vapor pressure had little effect on PM emissions. In contrast, the aromatic oxygenates caused significant increases in PM emissions (factors of 2 to 5) relative to the base gasoline. Thus, any effect of their oxygen atom on increasing local air-fuel ratio was outweighed by their low vapor pressure and high double-bond equivalent values. For most fuels and oxygenate blend components, PMI was a good predictor of PM emissions. However, the high boiling point, low vapor pressure oxygenates 2-phenylethanol and 2,4-xylenol produced lower PM emissions than predicted by PMI. This was likely because they did not fully evaporate and combust, and instead were swept into the lube oil.« less

Corresponding-states behavior of an ionic model fluid with variable dispersion interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weiss, Volker C., E-mail: volker.weiss@bccms.uni-bremen.de

2016-06-21

Guggenheim’s corresponding-states approach for simple fluids leads to a remarkably universal representation of their thermophysical properties. For more complex fluids, such as polar or ionic ones, deviations from this type of behavior are to be expected, thereby supplying us with valuable information about the thermodynamic consequences of the interaction details in fluids. Here, the gradual transition of a simple fluid to an ionic one is studied by varying the relative strength of the dispersion interactions compared to the electrostatic interactions among the charged particles. In addition to the effects on the reduced surface tension that were reported earlier [F. Leroymore » and V. C. Weiss, J. Chem. Phys. 134, 094703 (2011)], we address the shape of the coexistence curve and focus on properties that are related to and derived from the vapor pressure. These quantities include the enthalpy and entropy of vaporization, the boiling point, and the critical compressibility factor Z{sub c}. For all of these properties, the crossover from simple to characteristically ionic fluid is seen once the dispersive attraction drops below 20%–40% of the electrostatic attraction (as measured for two particles at contact). Below this threshold, ionic fluids display characteristically low values of Z{sub c} as well as large Guggenheim and Guldberg ratios for the reduced enthalpy of vaporization and the reduced boiling point, respectively. The coexistence curves are wider and more skewed than those for simple fluids. The results for the ionic model fluid with variable dispersion interactions improve our understanding of the behavior of real ionic fluids, such as inorganic molten salts and room temperature ionic liquids, by gauging the importance of different types of interactions for thermodynamic properties.« less

Operating and environmental performances of commercial-scale waste gasification and melting technology.

PubMed

Tanigaki, Nobuhiro; Fujinaga, Yasuka; Kajiyama, Hirohisa; Ishida, Yoshihiro

2013-11-01

Gasification technologies for waste processing are receiving increased interest. A lot of gasification technologies, including gasification and melting, have been developed in Japan and Europe. However, the flue gas and heavy metal behaviors have not been widely reported, even though those of grate furnaces have been reported. This article reports flue gas components of gasification and melting technology in different flue gas treatment systems. Hydrogen chloride concentrations at the inlet of the bag filter ranged between 171 and 180 mg Nm(-3) owing to de-acidification by limestone injection to the gasifier. More than 97.8% of hydrogen chlorides were removed by a bag filter in both of the flue gas treatment systems investigated. Sulfur dioxide concentrations at the inlet of the baghouse were 4.8 mg Nm(-3) and 12.7 mg Nm(-3), respectively. Nitrogen oxides are highly decomposed by a selective catalytic reduction system. Owing to the low regenerations of polychlorinated dibenzo-p-dioxins and furans, and the selective catalytic reduction system, the concentrations of polychlorinated dibenzo-p-dioxins and furans at the stacks were significantly lower without activated carbon injection. More than 99% of chlorine is distributed in fly ash. Low-boiling-point heavy metals, such as lead and zinc, are distributed in fly ash at rates of 97.6% and 96.5%, respectively. Most high-boiling-point heavy metals, such as iron and copper, are distributed in metal. It is also clarified that the slag is stable and contains few harmful heavy metals, such as lead. The heavy metal distribution behaviors are almost the same regardless of the compositions of the processed waste. These results indicate that the gasification of municipal solid waste constitutes an ideal approach to environmental conservation and resource recycling.

Modelling the effect of mixture components on permeation through skin.

PubMed

Ghafourian, T; Samaras, E G; Brooks, J D; Riviere, J E

2010-10-15

A vehicle influences the concentration of penetrant within the membrane, affecting its diffusivity in the skin and rate of transport. Despite the huge amount of effort made for the understanding and modelling of the skin absorption of chemicals, a reliable estimation of the skin penetration potential from formulations remains a challenging objective. In this investigation, quantitative structure-activity relationship (QSAR) was employed to relate the skin permeation of compounds to the chemical properties of the mixture ingredients and the molecular structures of the penetrants. The skin permeability dataset consisted of permeability coefficients of 12 different penetrants each blended in 24 different solvent mixtures measured from finite-dose diffusion cell studies using porcine skin. Stepwise regression analysis resulted in a QSAR employing two penetrant descriptors and one solvent property. The penetrant descriptors were octanol/water partition coefficient, logP and the ninth order path molecular connectivity index, and the solvent property was the difference between boiling and melting points. The negative relationship between skin permeability coefficient and logP was attributed to the fact that most of the drugs in this particular dataset are extremely lipophilic in comparison with the compounds in the common skin permeability datasets used in QSAR. The findings show that compounds formulated in vehicles with small boiling and melting point gaps will be expected to have higher permeation through skin. The QSAR was validated internally, using a leave-many-out procedure, giving a mean absolute error of 0.396. The chemical space of the dataset was compared with that of the known skin permeability datasets and gaps were identified for future skin permeability measurements. Copyright 2010 Elsevier B.V. All rights reserved.

Self-Propagating Frontal Polymerization in Water at Ambient Pressure

NASA Technical Reports Server (NTRS)

Olten, Nesrin; Kraigsley, Alison; Ronney, Paul D.

2003-01-01

Advances in polymer chemistry have led to the development of monomers and initiation agents that enable propagating free-radical polymerization fronts to exist. These fronts are driven by the exothermicity of the polymerization reaction and the transport of heat from the polymerized product to the reactant monomer/solvent/initiator solution. The thermal energy transported to the reactant solution causes the initiator to decompose, yielding free radicals, which start the free radical polymerization process as discussed in recent reviews. The use of polymerization processes based on propagating fronts has numerous applications. Perhaps the most important of these is that it enables rapid curing of polymers without external heating since the polymerization process itself provides the high temperatures necessary to initiate and sustain polymerization. This process also enables more uniform curing of arbitrarily thick samples since it does not rely on heat transfer from an external source, which will necessarily cause the temperature history of the sample to vary with distance from the surface according to a diffusion-like process. Frontal polymerization also enables filling and sealing of structures having cavities of arbitrary shape without having to externally heat the structure. Water at atmospheric pressure is most convenient solvent to employ and the most important for practical applications (because of the cost and environmental issues associated with DMSO and other solvents). Nevertheless, to our knowledge, steady, self-propagating polymerization fronts have not been reported in water at atmospheric pressure. Currently, polymerization fronts require a high boiling point solvent (either water at high pressures or an alternative solvent such as dimethyl sulfoxide (DMSO) (boiling point 189 C at atmospheric pressure.) Early work on frontal polymerization, employed pressures up to 5000 atm in order to avoid boiling of the monomer/solvent/initiator solution. High boiling point solutions are needed because in order to produce a propagating front, a high front temperature is needed to produce sufficiently rapid decomposition of the free radical initiator and subsequent free radical polymerization and heat release at a rate faster than heat losses remove thermal energy from the system. (While the conduction heat loss rate increases linearly with temperature, the free radical initiator decomposition is a high activation energy process whose rate increases much more rapidly than linearly with temperature, thus as the temperature decreases, the ratio of heat loss to heat generation increases, eventually leading to extinction of the front if the temperature is too low.) In order to obtain atmospheric pressure frontal polymerization in water, it is necessary to identify a monomer/initiator combination that is water soluble and will not extinguish even when the peak temperature (T*) is less than 100 C. In this work acrylic acid (AA) was chosen as the monomer because is it one of the most reactive monomers and can polymerize readily at low temperatures even without initiators. Ammonium persulfate (AP) was chosen as the initiator because it decomposes readily at low temperatures, produces relatively few bubbles and is commercially available. The propagation rates and extinction conditions of the fronts are studied for a range of AA and AP concentrations. Small amounts of fumed silica powder (Cab-o-sil, Cabot Corporation) were added to the solutions to inhibit buoyancy induced convection in the solutions; future studies will investigate the effects of buoyant convection within the solutions.

Quantifying the evolution of flow boiling bubbles by statistical testing and image analysis: toward a general model.

PubMed

Xiao, Qingtai; Xu, Jianxin; Wang, Hua

2016-08-16

A new index, the estimate of the error variance, which can be used to quantify the evolution of the flow patterns when multiphase components or tracers are difficultly distinguishable, was proposed. The homogeneity degree of the luminance space distribution behind the viewing windows in the direct contact boiling heat transfer process was explored. With image analysis and a linear statistical model, the F-test of the statistical analysis was used to test whether the light was uniform, and a non-linear method was used to determine the direction and position of a fixed source light. The experimental results showed that the inflection point of the new index was approximately equal to the mixing time. The new index has been popularized and applied to a multiphase macro mixing process by top blowing in a stirred tank. Moreover, a general quantifying model was introduced for demonstrating the relationship between the flow patterns of the bubble swarms and heat transfer. The results can be applied to investigate other mixing processes that are very difficult to recognize the target.

Fuel property effects on low-speed pre-ignition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jatana, Gurneesh S.; Splitter, Derek A.; Kaul, Brian C.

This work explores the dependence of fuel distillation and flame speed on low-speed pre-ignition (LSPI). Findings are based on cylinder pressure analysis, as well as the number count, clustering, intensity, duration, and onset crank angle of LSPI events. Four fuels were used, with three of the fuels being blends with gasoline, and the fourth being neat gasoline. The blended fuels consisted of single molecules of different molecular types: a ketone (cyclopentanone), an alcohol (2-methyl-1-butanol), and an aromatic (ethylbenzene). All three pure molecules have RON values within ±2 and boiling points within ±5 °C. These fuels were blended with gasoline tomore » a 25% mass fraction and were used to run the engine at identical LSPI prone operating conditions. The findings highlight that fuels with similar boiling properties and octane numbers can exhibit similar LSPI number counts, but with vastly different LSPI magnitudes and intensities. Moreover, the results highlight fundamental fuel properties such as flame speed are critical to characterizing the LSPI propensity and behavior of the fuel.« less

Investigation of Sensible and Latent Heat Storage System using various HTF

NASA Astrophysics Data System (ADS)

Beemkumar, N.; Karthikeyan, A.; Manoj, A.; Keerthan, J. S.; Stallan, Joseph Paul; Amithkishore, P.

2017-05-01

The objective of the work is investigating the latent heat storage system by varying heat transfer fluid (HTF). In this experiment, the effect of using different heat transfer fluids on the combined system is studied while using a low melting phase change material (PCM) i.e., paraffin wax. The heat transfer fluids chosen are water (low boiling fluid) and Therminol-66 (High boiling fluid). A comparison is made between the heat transfers by employing both the Heat transfer fluids. In the beginning, water is made to flow as the HTF and the charging process is undertaken followed by the discharging process by utilizing the different encapsulation materials namely, copper, aluminium and brass. These processes are then repeated for therminol-66 as HTF. At the end of the experiment it was concluded that even though therminol-66 enhances the latent heat storage capacity, water offers a higher sensible heat storage capacity, making it a better HTF for low melting PCM. Similar to above said process the experiments can be conducted for high and medium range melting point PCM with variation of HTF.

Fuel property effects on low-speed pre-ignition

DOE PAGES

Jatana, Gurneesh S.; Splitter, Derek A.; Kaul, Brian C.; ...

2018-05-30

This work explores the dependence of fuel distillation and flame speed on low-speed pre-ignition (LSPI). Findings are based on cylinder pressure analysis, as well as the number count, clustering, intensity, duration, and onset crank angle of LSPI events. Four fuels were used, with three of the fuels being blends with gasoline, and the fourth being neat gasoline. The blended fuels consisted of single molecules of different molecular types: a ketone (cyclopentanone), an alcohol (2-methyl-1-butanol), and an aromatic (ethylbenzene). All three pure molecules have RON values within ±2 and boiling points within ±5 °C. These fuels were blended with gasoline tomore » a 25% mass fraction and were used to run the engine at identical LSPI prone operating conditions. The findings highlight that fuels with similar boiling properties and octane numbers can exhibit similar LSPI number counts, but with vastly different LSPI magnitudes and intensities. Moreover, the results highlight fundamental fuel properties such as flame speed are critical to characterizing the LSPI propensity and behavior of the fuel.« less

Quantifying the evolution of flow boiling bubbles by statistical testing and image analysis: toward a general model

PubMed Central

Xiao, Qingtai; Xu, Jianxin; Wang, Hua

2016-01-01

A new index, the estimate of the error variance, which can be used to quantify the evolution of the flow patterns when multiphase components or tracers are difficultly distinguishable, was proposed. The homogeneity degree of the luminance space distribution behind the viewing windows in the direct contact boiling heat transfer process was explored. With image analysis and a linear statistical model, the F-test of the statistical analysis was used to test whether the light was uniform, and a non-linear method was used to determine the direction and position of a fixed source light. The experimental results showed that the inflection point of the new index was approximately equal to the mixing time. The new index has been popularized and applied to a multiphase macro mixing process by top blowing in a stirred tank. Moreover, a general quantifying model was introduced for demonstrating the relationship between the flow patterns of the bubble swarms and heat transfer. The results can be applied to investigate other mixing processes that are very difficult to recognize the target. PMID:27527065

Effect of Variable Solvents on Particle Size of Geranium Oil-Loaded Solid Lipid Nanoparticle (Ge-SLN) For Mosquito Repellent Applications

NASA Astrophysics Data System (ADS)

Asnawi, Syalwati; Aziz, Azila A.; Aziz, Ramlan A.

2009-06-01

A new delivery system for insect repellent is proposed by the incorporation of geranium oil into solid lipid nanoparticle (SLN). A variety of solvents which act as co-surfactants, were introduced to increase the particle size of GE-SLN. Ethanol, which has a high boiling point and a long chain alcohol produced larger particle than dichloromethane. The structure of SLN was not stable when methanol and acetone were used as co-solvents. Concentration of solvents can also influence the size of SLN. In vitro release experiments showed that SLN was able to reduce the rapid evaporation of geranium oil.

Development of a cryogenic mixed fluid J-T cooling computer code, 'JTMIX'

NASA Technical Reports Server (NTRS)

Jones, Jack A.

1991-01-01

An initial study was performed for analyzing and predicting the temperatures and cooling capacities when mixtures of fluids are used in Joule-Thomson coolers and in heat pipes. A computer code, JTMIX, was developed for mixed gas J-T analysis for any fluid combination of neon, nitrogen, various hydrocarbons, argon, oxygen, carbon monoxide, carbon dioxide, and hydrogen sulfide. When used in conjunction with the NIST computer code, DDMIX, it has accurately predicted order-of-magnitude increases in J-T cooling capacities when various hydrocarbons are added to nitrogen, and it predicts nitrogen normal boiling point depressions to as low as 60 K when neon is added.

A study of the mechanism of metal deposition by the laser-induced forward transfer process

NASA Astrophysics Data System (ADS)

Adrian, F. J.; Bohandy, J.; Kim, B. F.; Jette, A. N.; Thompson, P.

1987-10-01

The mechanism of the laser-induced forward transfer (LIFT) technique for transferring metal features from a film to a substrate is examined by using the one-dimensional thermal diffusion equation with a moving solid-melt boundary to model the heating, melting, and vaporization of the metal film by the laser. For typical LIFT conditions the calculations show that the back of the film (i.e., the part exposed to the laser) will reach the boiling point before the film melts through, which supports the qualitative picture that the LIFT process involves vapor-driven propulsion of metal from the film onto the target.

Surfactant studies for bench-scale operation

NASA Technical Reports Server (NTRS)

Hickey, Gregory S.; Sharma, Pramod K.

1992-01-01

A phase 2 study was initiated to investigate surfactant-assisted coal liquefaction, with the objective of quantifying the enhancement in liquid yields and product quality. This publication covers the first quarter of work. The major accomplishments were: the refurbishment of the high-pressure, high-temperature reactor autoclave, the completion of four coal liquefaction runs with Pittsburgh #8 coal, two each with and without sodium lignosulfonate surfactant, and the development of an analysis scheme for the product liquid filtrate and filter cake. Initial results at low reactor temperatures show that the addition of the surfactant produces an improvement in conversion yields and an increase in lighter boiling point fractions for the filtrate.

Cascaded organic rankine cycles for waste heat utilization

DOEpatents

Radcliff, Thomas D [Vernon, CT; Biederman, Bruce P [West Hartford, CT; Brasz, Joost J [Fayetteville, NY

2011-05-17

A pair of organic Rankine cycle systems (20, 25) are combined and their respective organic working fluids are chosen such that the organic working fluid of the first organic Rankine cycle is condensed at a condensation temperature that is well above the boiling point of the organic working fluid of the second organic Rankine style system, and a single common heat exchanger (23) is used for both the condenser of the first organic Rankine cycle system and the evaporator of the second organic Rankine cycle system. A preferred organic working fluid of the first system is toluene and that of the second organic working fluid is R245fa.

Imprintable, bendable, and shape-conformable polymer electrolytes for versatile-shaped lithium-ion batteries.

PubMed

Kil, Eun-Hye; Choi, Keun-Ho; Ha, Hyo-Jeong; Xu, Sheng; Rogers, John A; Kim, Mi Ri; Lee, Young-Gi; Kim, Kwang Man; Cho, Kuk Young; Lee, Sang-Young

2013-03-13

A class of imprintable, bendable, and shape-conformable polymer electrolyte with excellent electrochemical performance in a lithium battery system is reported. The material consists of a UV-cured polymer matrix, high-boiling point liquid electrolyte, and Al2 O3 nanoparticles, formulated for use in lithium-ion batteries with 3D-structured electrodes or flexible characteristics. The unique structural design and well-tuned rheological characteristics of the UV-curable electrolyte mixture, in combination with direct UV-assisted nanoimprint lithography, allow the successful fabrication of polymer electrolytes in geometries not accessible with conventional materials. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nanocrystalline hydroxyapatite ceramics prepared by hydrolysis in polyol medium

NASA Astrophysics Data System (ADS)

Mechay, Abderrahmen; Feki, Hafed E. L.; Schoenstein, Fréderic; Jouini, Noureddine

2012-07-01

This Letter describes a new approach for the synthesis of hydroxyapatite nanoparticles, which involves precipitation and hydrolysis reactions conducted in polyol medium. In fact, ammonium-hydrogen phosphate and calcium nitrate were dissolved in polyol, and then heated at the boiling point of the polyol (ethane1, 2diol or propane1, 2diol). Besides, the phase and composition of the polycrystalline were studied by TGA/DTA, FT-IR, TEM and XRD techniques. The nanoparticles thus obtained present interesting morphological characters varying from needle to very thin platelet. Moreover, the hydroxyapatite prepared in ployol shows higher cristallinity in comparison with that obtained by other 'chimie douce' methods.

Process to recycle shredder residue

DOEpatents

Jody, Bassam J.; Daniels, Edward J.; Bonsignore, Patrick V.

2001-01-01

A system and process for recycling shredder residue, in which separating any polyurethane foam materials are first separated. Then separate a fines fraction of less than about 1/4 inch leaving a plastics-rich fraction. Thereafter, the plastics rich fraction is sequentially contacted with a series of solvents beginning with one or more of hexane or an alcohol to remove automotive fluids; acetone to remove ABS; one or more of EDC, THF or a ketone having a boiling point of not greater than about 125.degree. C. to remove PVC; and one or more of xylene or toluene to remove polypropylene and polyethylene. The solvents are recovered and recycled.

Oscillation effects upon film boiling from a sphere.

NASA Technical Reports Server (NTRS)

Schmidt, W. E.; Witte, L. C.

1972-01-01

Heat transfer rates from a silver-plated copper sphere, 0.75 in. in diameter, were studied by high speed photography during oscillations of the sphere in saturated liquid nitrogen and Freon-11. The oscillation frequencies ranged from zero to 13 Hz, and the amplitude-to-diameter ratio varied from zero to 2.67. The sphere was supported by a thin-walled stainless steel tube and carried a thermocouple attached near the lower stagnation point. A Fastax WF-3 16mm movie camera was used at about 2000 frames/sec. The differences in the vapor removal process at lower and higher oscillation frequencies are discussed.

Ionic liquids as advantageous solvents for headspace gas chromatography of compounds with low vapor pressure.

PubMed

Andre, M; Loidl, J; Laus, G; Schottenberger, H; Bentivoglio, G; Wurst, K; Ongania, K-H

2005-01-15

The potential of ionic liquids as solvents for headspace gas chromatography was investigated. Three compounds with boiling points above 200 degrees C were selected to demonstrate the feasibility of the concept described. 2-Ethylhexanoic acid, formamide, and tri-n-butylamine as examples of acidic, neutral, and basic analytes were dissolved in acidic 1-n-butyl-3-methylimidazolium hydrogen sulfate (1), neutral 1-n-butyl-2,3-dimethylimidazolium dicyanamide (2), and 2 containing 1,8-diazabicyclo[5.4.0]undec-7-ene to adjust basic conditions. All analytes could be determined with limits of detection and limits of quantification in the low-ppm concentration range.

Chemistry explained by topology: an alternative approach.

PubMed

Galvez, Jorge; Villar, Vincent M; Galvez-Llompart, Maria; Amigó, José M

2011-05-01

Molecular topology can be considered an application of graph theory in which the molecular structure is characterized through a set of graph-theoretical descriptors called topological indices. Molecular topology has found applications in many different fields, particularly in biology, chemistry, and pharmacology. The first topological index was introduced by H. Wiener in 1947 [1]. Although its very first application was the prediction of the boiling points of the alkanes, the Wiener index has demonstrated since then a predictive capability far beyond that. Along with the Wiener index, in this paper we focus on a few pioneering topological indices, just to illustrate the connection between physicochemical properties and molecular connectivity.

Esterification Reaction of Glycerol and Palm Oil Oleic Acid Using Methyl Ester Sulfonate Acid Catalyst as Drilling Fluid Formulation

NASA Astrophysics Data System (ADS)

Sari, V. I.; Hambali, E.; Suryani, A.; Permadi, P.

2017-02-01

Esterification reaction between glycerol with palm oil oleic acid to produce glycerol ester and one of the utilization of glycerol esters is as ingredients of drilling fluids formula for oil drilling needs. The purpose of this research is to get the best conditions of the esterification process. The esterification reaction does with the reactants is glycerol with purity of 97.6%, palm oil oleic acid with the molar ratio is 1:1, Methyl Ester Sulfonate Acid (MESA) catalyst 0.5%, and stirring speed 400 rpm. The temperature range of 180°C to 240°C and the processing time between 120 to 180 minutes. The results showed that the best conditions of the esterification reaction at the temperature 240°C and time process are 180 minute. The increasing temperature resulted that the acid number decreases and causing the conversion increased. The maximum conversion is 99.24%, density 0.93 g/cm3, flash point 241°C, pour point -3°C, the boiling point of 244 °C, the acid value of 1.90 mg KOH/g sample, kinematic viscosity 31.51 cSt (40°C), surface tension 37.0526 dyne/cm and GCMS identification, glycerol ester at 22,256 retention time (minutes) and wide area 73.75 (%). From the research results obtained glycerol ester with characteristics suitable for drilling fluid formulations.

Method of producing nano-scaled graphene and inorganic platelets and their nanocomposites

DOEpatents

Jang, Bor Z [Centerville, OH; Zhamu, Aruna [Centerville, OH

2011-02-22

Disclosed is a method of exfoliating a layered material (e.g., graphite and graphite oxide) to produce nano-scaled platelets having a thickness smaller than 100 nm, typically smaller than 10 nm, and often between 0.34 nm and 1.02 nm. The method comprises: (a) subjecting the layered material in a powder form to a halogen vapor at a first temperature above the melting point or sublimation point of the halogen at a sufficient vapor pressure and for a duration of time sufficient to cause the halogen molecules to penetrate an interlayer space of the layered material, forming a stable halogen-intercalated compound; and (b) heating the halogen-intercalated compound at a second temperature above the boiling point of the halogen, allowing halogen atoms or molecules residing in the interlayer space to exfoliate the layered material to produce the platelets. Alternatively, rather than heating, step (a) is followed by a step of dispersing the halogen-intercalated compound in a liquid medium which is subjected to ultrasonication for exfoliating the halogen-intercalated compound to produce the platelets, which are dispersed in the liquid medium. The halogen can be readily captured and re-used, thereby significantly reducing the impact of halogen to the environment. The method can further include a step of dispersing the platelets in a polymer or monomer solution or suspension as a precursor step to nanocomposite fabrication.

Method of producing nano-scaled graphene and inorganic platelets and their nanocomposites

DOEpatents

Jang, Bor Z [Centerville, OH; Zhamu, Aruna [Centerville, OH

2012-02-14

Disclosed is a method of exfoliating a layered material (e.g., graphite and graphite oxide) to produce nano-scaled platelets having a thickness smaller than 100 nm, typically smaller than 10 nm, and often between 0.34 nm and 1.02 nm. The method comprises: (a) subjecting the layered material in a powder form to a halogen vapor at a first temperature above the melting point or sublimation point of the halogen at a sufficient vapor pressure and for a duration of time sufficient to cause the halogen molecules to penetrate an interlayer space of the layered material, forming a stable halogen-intercalated compound; and (b) heating the halogen-intercalated compound at a second temperature above the boiling point of the halogen, allowing halogen atoms or molecules residing in the interlayer space to exfoliate the layered material to produce the platelets. Alternatively, rather than heating, step (a) is followed by a step of dispersing the halogen-intercalated compound in a liquid medium which is subjected to ultrasonication for exfoliating the halogen-intercalated compound to produce the platelets, which are dispersed in the liquid medium. The halogen can be readily captured and re-used, thereby significantly reducing the impact of halogen to the environment. The method can further include a step of dispersing the platelets in a polymer or monomer solution or suspension as a precursor step to nanocomposite fabrication.

Experimental investigation on no-vent fill process using tetrafluoromethane (CF4)

NASA Astrophysics Data System (ADS)

Kim, Youngcheol; Lee, Cheonkyu; Park, Jiho; Seo, Mansu; Jeong, Sangkwon

2016-03-01

This paper investigates the transfer of liquid cryogens using a no-vent fill (NVF) process experimentally to identify the dominant NVF parameters. The experimental apparatus has been fabricated with extensive instrumentations to precisely study the effects of each NVF parameter. Liquid tetrafluoromethane (CF4) is selected as the working fluid due to its similar molecular structures and similar normal boiling point and triple point with liquid methane which has been considered as an attractive future cryogenic propellant. The experimental results show that the initial receiver tank wall temperature and the incoming liquid temperature are the primary factors that characterize the (non-equilibrium) thermodynamic state at the start of a NVF transfer. The supply pressure is also critical as it indicates the ability to condense vapor in the receiver tank. A non-dimensional map based on energy balance is proposed to find acceptable initial conditions of the filling volume at the desired final tank pressure. The non-dimensional map shows good agreement with the NVF data not only in this paper but also in the previous research.

Fulfillment of GMP standard, halal standard, and applying HACCP for production process of beef floss (Case study: Ksatria enterprise)

NASA Astrophysics Data System (ADS)

A'diat, Arkan Addien Al; Liquiddanu, Eko; Laksono, Pringgo Widyo; Sutopo, Wahyudi; Suletra, I. Wayan

2018-02-01

Along with the increasing number of the modern retail business in Indonesia, give an opportunity to small and medium enterprise (SME) to sell its products through the modern retailer. There are some obstacles faced by the SMEs, one of them is about product standard. Product standard that must be owned by SMEs are GMP standard and halal standard. This research was conducted to know the fulfillment by the beef floss enterprise in jagalan in fulfilling the GMP standard and halal. In addition, Hazard Analysis and Critical Control Points (HACCP) system was applied to analyze the process. HACCP which used in this research was based on the seven principles in SNI (Indonesian National Standard) 01-4852-1998. The seven principles included hazard analysis, critical control point (CCP) determination, critical limit establishment, CCP monitor system establishment, corrective action establishment, verification, and also documentation establishment that must be applied in preparing HACCP plan. Based on this case study, it is concluded that there were 5 CCPs : the boiling process, roasting process, frying process, the beef floss draining process, and the packaging process.

Evaluation of the application of some gas chromatographic methods for the determination of properties of synthetic fuels

NASA Technical Reports Server (NTRS)

Antoine, A. C.

1979-01-01

The purpose of the investigation was to evaluate the applicability, to some synthetic fuels, of some gas chromatographic methods now under development for use with petroleum based fuels. Thirty-two jet and diesel fuel samples which were prepared from oil shale and coal syncrudes were examined. The boiling range distribution of each was determined by gas chromatography, and from that data distillation properties were calculated. The calculated results gave sufficient agreement with the measured values that the equations could be useable in their present form. Bulk fuel properties were calculated for the sixteen JP-5 and Diesel No. 2 type fuels. The results show that the equations would not give useable results. Capillary column gas chromatography was used to determine the n-alkane content of the eight JP-5 type samples and the results related to the observed freezing points. The results show that the concentrations of the long straight chain molecules in the fuels exert influence on the freezing point but are not the complete controlling factor.

Evaluation of the application of some gas chromatographic methods for the determination of properties of synthetic fuels

NASA Technical Reports Server (NTRS)

Antoine, A. C.

1978-01-01

The purpose of the investigation was to evaluate the applicability, to some synthetic fuels, of some gas chromatographic methods now under development for use with petroleum based fuels. Thirty-two jet and diesel fuel samples which were prepared from oil shale and coal syncrudes were examined. The boiling range distribution of each was determined by gas chromatography, and from that data distillation properties were calculated. The calculated results gave sufficient agreement with the measured values that the equations could be useable in their present form. Bulk fuel properties were calculated for the 16 JP-5 and Diesel No. 2 type fuels. The results show that the equations would not give useable results. Capillary column gas chromatography was used to determine the n-alkane content of the eight JP-5 type samples and the results related to the observed freezing points. The results show that the concentrations of the long straight chain molecules in the fuels exert influence on the freezing point but are not the complete controlling factor.

Physical Properties of Pyridinium Fluorohydrogenate, [pyridine · H+][H2F3]-

NASA Astrophysics Data System (ADS)

Hulse, Ryan; Singh, Rajiv

2008-12-01

Ionic liquids (ILs), also referred to as molten salts, have found application as electrolytes for batteries and super-capacitors, in electroplating baths, as designer solvents, and as reaction media. A few of the desired properties of a super-capacitor electrolyte are nonflammability, thermal stability, and electrochemical stability. ILs containing aromatic cations have been shown to have low viscosity which results in a high electrochemical conductivity. There is a delicate balance between increasing the thermal stability, or decreasing the melting point, and increasing the electrochemical conductivity of the IL. This study focuses on pyridinium fluorohydrogenate, [pyridine · H+][H2F3]-. Pyridinium fluorohydrogenate has been synthesized by the reaction of pyridine and anhydrous hydrofluoric acid. This IL has a relatively high electrical conductivity (~98 mS · cm-1 at 23 °C), a wide electrochemical window, and a boiling point of 186 °C. A stable gel can also be formed by combining [pyridine · H+][H2F3]- and a super absorbent polymer such as polyacrylic acid. The gel adds mechanical stability to the matrix while not greatly affecting the conductivity of the IL.

Synthesis of Lithium Metal Oxide Nanoparticles by Induction Thermal Plasmas.

PubMed

Tanaka, Manabu; Kageyama, Takuya; Sone, Hirotaka; Yoshida, Shuhei; Okamoto, Daisuke; Watanabe, Takayuki

2016-04-06

Lithium metal oxide nanoparticles were synthesized by induction thermal plasma. Four different systems-Li-Mn, Li-Cr, Li-Co, and Li-Ni-were compared to understand formation mechanism of Li-Me oxide nanoparticles in thermal plasma process. Analyses of X-ray diffractometry and electron microscopy showed that Li-Me oxide nanoparticles were successfully synthesized in Li-Mn, Li-Cr, and Li-Co systems. Spinel structured LiMn₂O₄ with truncated octahedral shape was formed. Layer structured LiCrO₂ or LiCoO₂ nanoparticles with polyhedral shapes were also synthesized in Li-Cr or Li-Co systems. By contrast, Li-Ni oxide nanoparticles were not synthesized in the Li-Ni system. Nucleation temperatures of each metal in the considered system were evaluated. The relationship between the nucleation temperature and melting and boiling points suggests that the melting points of metal oxides have a strong influence on the formation of lithium metal oxide nanoparticles. A lower melting temperature leads to a longer reaction time, resulting in a higher fraction of the lithium metal oxide nanoparticles in the prepared nanoparticles.

Microporous plastic member such as a battery separator and process for making same

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sundberg, E.G.; Campbell, G.A.; Doucette, E.I.

A process for producing a microporous plastic member useful as a battery separator comprises the following operations: forming a coherent dough by mixing a vinyl chloride resin with a plasticizing amount of a first solvent and with finely divided particles of a filler which contains volatilizable releasable constituent by heating and which shrinks substantially and irreversibly upon release of the volatilizable constituent, an example of which is hydrated silica; forming the solvent-containing dough into a shaped member; extracting the first solvent from the member before any substantial evaporation of solvent occurs by contacting it with a second solvent in amore » liquid bath at a temperature substantially below the boiling point of any liquid present, the second solvent being one which is capable of dissolving the first solvent without dissolving the resin and the filler, thereby deplasticizing the member by extractively removing the first solvent from the member; and thereafter heating the member at an elevated temperature but below the softening point of the resin until the filler is shrunk within the member by release of its volatilizable content. 10 claims.« less

Computational assessment of several hydrogen-free high energy compounds.

PubMed

Tan, Bisheng; Huang, Ming; Long, Xinping; Li, Jinshan; Fan, Guijuan

2016-01-01

Tetrazino-tetrazine-tetraoxide (TTTO) is an attractive high energy compound, but unfortunately, it is not yet experimentally synthesized so far. Isomerization of TTTO leads to its five isomers, bond-separation energies were empolyed to compare the global stability of six compounds, it is found that isomer 1 has the highest bond-separation energy (1204.6kJ/mol), compared with TTTO (1151.2kJ/mol); thermodynamic properties of six compounds were theoretically calculated, including standard formation enthalpies (solid and gaseous), standard fusion enthalpies, standard vaporation enthalpies, standard sublimation enthalpies, lattice energies and normal melting points, normal boiling points; their detonation performances were also computed, including detonation heat (Q, cal/g), detonation velocity (D, km/s), detonation pressure (P, GPa) and impact sensitivity (h50, cm), compared with TTTO (Q=1311.01J/g, D=9.228km/s, P=40.556GPa, h50=12.7cm), isomer 5 exhibites better detonation performances (Q=1523.74J/g, D=9.389km/s, P=41.329GPa, h50= 28.4cm). Copyright © 2015 Elsevier Inc. All rights reserved.

SCC of 2304 Duplex Stainless Steel—Microstructure, Residual Stress and Surface Grinding Effects

PubMed Central

Zhou, Nian; Peng, Ru Lin; Schönning, Mikael; Pettersson, Rachel

2017-01-01

The influence of surface grinding and microstructure on chloride induced stress corrosion cracking (SCC) behavior of 2304 duplex stainless steel has been investigated. Grinding operations were performed both parallel and perpendicular to the rolling direction of the material. SCC tests were conducted in boiling magnesium chloride according to ASTM G36; specimens were exposed both without external loading and with varied levels of four-point bend loading. Residual stresses were measured on selected specimens before and after exposure using the X-ray diffraction technique. In addition, in-situ surface stress measurements subjected to four-point bend loading were performed to evaluate the deviation between the actual applied loading and the calculated values according to ASTM G39. Micro-cracks, initiated by grinding induced surface tensile residual stresses, were observed for all the ground specimens but not on the as-delivered surfaces. Loading transverse to the rolling direction of the material increased the susceptibility to chloride induced SCC. Grinding induced tensile residual stresses and micro-notches in the as-ground surface topography were also detrimental. PMID:28772582