A Direct Numerical Simulation of a Temporally Evolving Liquid-Gas Turbulent Mixing Layer

NASA Astrophysics Data System (ADS)

Vu, Lam Xuan; Chiodi, Robert; Desjardins, Olivier

2017-11-01

Air-blast atomization occurs when streams of co-flowing high speed gas and low speed liquid shear to form drops. Air-blast atomization has numerous industrial applications from combustion engines in jets to sprays used for medical coatings. The high Reynolds number and dynamic pressure ratio of a realistic air-blast atomization case requires large eddy simulation and the use of multiphase sub-grid scale (SGS) models. A direct numerical simulations (DNS) of a temporally evolving mixing layer is presented to be used as a base case from which future multiphase SGS models can be developed. To construct the liquid-gas mixing layer, half of a channel flow from Kim et al. (JFM, 1987) is placed on top of a static liquid layer that then evolves over time. The DNS is performed using a conservative finite volume incompressible multiphase flow solver where phase tracking is handled with a discretely conservative volume of fluid method. This study presents statistics on velocity and volume fraction at different Reynolds and Weber numbers.

Dissolved Gases and Ice Fracturing During the Freezing of a Multicellular Organism: Lessons from Tardigrades.

PubMed

Kletetschka, Gunther; Hruba, Jolana

2015-01-01

Three issues are critical for successful cryopreservation of multicellular material: gases dissolved in liquid, thermal conductivity of the tissue, and localization of microstructures. Here we show that heat distribution is controlled by the gas amount dissolved in liquids and that when changing the liquid into solid, the dissolved gases either form bubbles due to the absence of space in the lattice of solids and/or are migrated toward the concentrated salt and sugar solution at the cost of amount of heat required to be removed to complete a solid-state transition. These factors affect the heat distribution in the organs to be cryopreserved. We show that the gas concentration issue controls fracturing of ice when freezing. There are volumetric changes not only when changing the liquid into solid (volume increases) but also reduction of the volume when reaching lower temperatures (volume decreases). We discuss these issues parallel with observations of the cryosurvivability of multicellular organisms, tardigrades, and discuss their analogy for cryopreservation of large organs.

A device for controlled jet injection of large volumes of liquid.

PubMed

Mckeage, James W; Ruddy, Bryan P; Nielsen, Poul M F; Taberner, Andrew J

2016-08-01

We present a needle-free jet injection device controllably actuated by a voice coil and capable of injecting up to 1.3 mL. This device is used to perform jet injections of ~900 μL into porcine tissue. This is the first time that delivery of such a large volume has been reported using an electronically controllable device. The controllability of this device is demonstrated with a series of ejections where the desired volume is ejected to within 1 % during an injection at a predetermined jet velocity.

Liquid scintillator composition optimization for use in ultra-high energy cosmic ray detector systems

NASA Astrophysics Data System (ADS)

Beznosko, Dmitriy; Batyrkhanov, Ayan; Iakovlev, Alexander; Yelshibekov, Khalykbek

2017-06-01

The Horizon-T (HT) detector system and the currently under R&D HT-KZ detector system are designed for the detection of Extensive Air Showers (EAS) with energies above ˜1016 eV (˜1017 eV for HT-KZ). The main challenges in both detector systems are the fast time resolutions needed for studying the temporary structure of EAS, and the extremely wide dynamic range needed to study the spatial distribution of charged particles in EAS disks. In order to detect the low-density of charged particles far from the EAS axis, a large-area detector is needed. Liquid scintillator with low cost would be a possible solution for such a detector, including the recently developed safe and low-cost water-based liquid scintillators. Liquid organic scintillators give a fast and high light yield (LY) for charged particle detection. It is similar to plastic scintillator in properties but is cost effective for large volumes. With liquid scintillator, one can create detection volumes that are symmetric and yet retain high LY detection. Different wavelength shifters affect the scintillation light by changing the output spectrum into the best detection region. Results of the latest studies of the components optimization in the liquid scintillator formulae are presented.

Utilization of Low Gravity Environment for Measuring Liquid Viscosity

NASA Technical Reports Server (NTRS)

Antar, Basil N.; Ethridge, Edwin

1998-01-01

The method of drop coalescence is used for determining the viscosity of highly viscous undercooled liquids. Low gravity environment is necessary in order to allow for examining large volumes affording much higher accuracy for the viscosity calculations than possible for smaller volumes available under 1 - g conditions. The drop coalescence method is preferred over the drop oscillation technique since the latter method can only be applied for liquids with vanishingly small viscosities. The technique developed relies on both the highly accurate solution of the Navier-Stokes equations as well as on data from experiments conducted in near zero gravity environment. Results are presented for method validation experiments recently performed on board the NASA/KC-135 aircraft. While the numerical solution was produced using the Boundary Element Method. In these tests the viscosity of a highly viscous liquid, glycerine at room temperature, was determined using the liquid coalescence method. The results from these experiments will be discussed.

Robotic liquid handling and automation in epigenetics.

PubMed

Gaisford, Wendy

2012-10-01

Automated liquid-handling robots and high-throughput screening (HTS) are widely used in the pharmaceutical industry for the screening of large compound libraries, small molecules for activity against disease-relevant target pathways, or proteins. HTS robots capable of low-volume dispensing reduce assay setup times and provide highly accurate and reproducible dispensing, minimizing variation between sample replicates and eliminating the potential for manual error. Low-volume automated nanoliter dispensers ensure accuracy of pipetting within volume ranges that are difficult to achieve manually. In addition, they have the ability to potentially expand the range of screening conditions from often limited amounts of valuable sample, as well as reduce the usage of expensive reagents. The ability to accurately dispense lower volumes provides the potential to achieve a greater amount of information than could be otherwise achieved using manual dispensing technology. With the emergence of the field of epigenetics, an increasing number of drug discovery companies are beginning to screen compound libraries against a range of epigenetic targets. This review discusses the potential for the use of low-volume liquid handling robots, for molecular biological applications such as quantitative PCR and epigenetics.

Fast automated dual-syringe based dispersive liquid-liquid microextraction coupled with gas chromatography-mass spectrometry for the determination of polycyclic aromatic hydrocarbons in environmental water samples.

PubMed

Guo, Liang; Tan, Shufang; Li, Xiao; Lee, Hian Kee

2016-03-18

An automated procedure, combining low density solvent based solvent demulsification dispersive liquid-liquid microextraction (DLLME) with gas chromatography-mass spectrometry analysis, was developed for the determination of polycyclic aromatic hydrocarbons (PAHs) in environmental water samples. Capitalizing on a two-rail commercial autosampler, fast solvent transfer using a large volume syringe dedicated to the DLLME process, and convenient extract collection using a small volume microsyringe for better GC performance were enabled. Extraction parameters including the type and volume of extraction solvent, the type and volume of dispersive solvent and demulsification solvent, extraction and demulsification time, and the speed of solvent injection were investigated and optimized. Under the optimized conditions, the linearity ranged from 0.1 to 50 μg/L, 0.2 to 50 μg/L, and 0.5 to 50 μg/L, depending on the analytes. Limits of detection were determined to be between 0.023 and 0.058 μg/L. The method was applied to determine PAHs in environmental water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Determination of diflubenzuron and chlorbenzuron in fruits by combining acetonitrile-based extraction with dispersive liquid-liquid microextraction followed by high-performance liquid chromatography.

PubMed

Ruan, Chunqiang; Zhao, Xiang; Liu, Chenglan

2015-09-01

In this study, a simple and low-organic-solvent-consuming method combining an acetonitrile-partitioning extraction procedure followed by "quick, easy, cheap, effective, rugged and safe" cleanup with ionic-liquid-based dispersive liquid-liquid microextraction and high-performance liquid chromatography with diode array detection was developed for the determination of diflubenzuron and chlorbenzuron in grapes and pears. Ionic-liquid-based dispersive liquid-liquid microextraction was performed using the ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate as the extractive solvent and acetonitrile extract as the dispersive solvent. The main factors influencing the efficiency of the dispersive liquid-liquid microextraction were evaluated, including the extractive solvent type and volume and the dispersive solvent volume. The validation parameters indicated the suitability of the method for routine analyses of benzoylurea insecticides in a large number of samples. The relative recoveries at three spiked levels ranged between 98.6 and 109.3% with relative standard deviations of less than 5.2%. The limit of detection was 0.005 mg/kg for the two insecticides. The proposed method was successfully used for the rapid determination of diflubenzuron and chlorbenzuron residues in real fruit samples. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Catalyst for hydrotreating carbonaceous liquids

DOEpatents

Berg, Lloyd; McCandless, Frank P.; Ramer, Ronald J.

1982-01-01

A catalyst for denitrogenating and desulfurating carbonaceous liquid such as solvent refined coal includes catalytic metal oxides impregnated within a porous base of mostly alumina with relatively large pore diameters, surface area and pore volume. The base material includes pore volumes of 0.7-0.85 ml/g, surface areas of 200-350 m.sup.2 /g and pore diameters of 85-200 Angstroms. The catalytic metals impregnated into these base materials include the oxides of Group VI metals, molybdenum and tungsten, and the oxides of Group VIII metals, nickel and cobalt, in various combinations. These catalysts and bases in combination have effectively promoted the removal of chemically combined sulfur and nitrogen within a continuous flowing mixture of carbonaceous liquid and hydrogen gas.

Dispersive liquid-liquid microextraction for the determination of nitrophenols in soils by microvial insert large volume injection-gas chromatography-mass spectrometry.

PubMed

Cacho, J I; Campillo, N; Viñas, P; Hernández-Córdoba, M

2016-07-22

A rapid and sensitive procedure for the determination of six NPs in soils by gas chromatography and mass spectrometry (GC-MS) is proposed. Ultrasound assisted extraction (UAE) is used for NP extraction from soil matrices to an organic solvent, while the environmentally friendly technique dispersive liquid-liquid microextraction (DLLME) is used for the preconcentration of the resulting UAE extracts. NPs were derivatized by applying an "in-situ" acetylation procedure, before being injected into the GC-MS system using microvial insert large volume injection (LVI). Several parameters affecting UAE, DLLME, derivatization and injection steps were investigated. The optimized procedure provided recoveries of 86-111% from spiked samples. Precision values of the procedure (expressed as relative standard deviation, RSD) lower than 12%, and limits of quantification ranging from 1.3 to 2.6ngg(-1), depending on the compound, were obtained. Twenty soil samples, obtained from military, industrial and agricultural areas, were analyzed by the proposed method. Two of the analytes were quantified in two of the samples obtained from industrial areas, at concentrations in the 4.8-9.6ngg(-1) range. Copyright © 2016 Elsevier B.V. All rights reserved.

Recurrence interval analysis of trading volumes

NASA Astrophysics Data System (ADS)

Ren, Fei; Zhou, Wei-Xing

2010-06-01

We study the statistical properties of the recurrence intervals τ between successive trading volumes exceeding a certain threshold q . The recurrence interval analysis is carried out for the 20 liquid Chinese stocks covering a period from January 2000 to May 2009, and two Chinese indices from January 2003 to April 2009. Similar to the recurrence interval distribution of the price returns, the tail of the recurrence interval distribution of the trading volumes follows a power-law scaling, and the results are verified by the goodness-of-fit tests using the Kolmogorov-Smirnov (KS) statistic, the weighted KS statistic and the Cramér-von Mises criterion. The measurements of the conditional probability distribution and the detrended fluctuation function show that both short-term and long-term memory effects exist in the recurrence intervals between trading volumes. We further study the relationship between trading volumes and price returns based on the recurrence interval analysis method. It is found that large trading volumes are more likely to occur following large price returns, and the comovement between trading volumes and price returns is more pronounced for large trading volumes.

Recurrence interval analysis of trading volumes.

PubMed

Ren, Fei; Zhou, Wei-Xing

2010-06-01

We study the statistical properties of the recurrence intervals τ between successive trading volumes exceeding a certain threshold q. The recurrence interval analysis is carried out for the 20 liquid Chinese stocks covering a period from January 2000 to May 2009, and two Chinese indices from January 2003 to April 2009. Similar to the recurrence interval distribution of the price returns, the tail of the recurrence interval distribution of the trading volumes follows a power-law scaling, and the results are verified by the goodness-of-fit tests using the Kolmogorov-Smirnov (KS) statistic, the weighted KS statistic and the Cramér-von Mises criterion. The measurements of the conditional probability distribution and the detrended fluctuation function show that both short-term and long-term memory effects exist in the recurrence intervals between trading volumes. We further study the relationship between trading volumes and price returns based on the recurrence interval analysis method. It is found that large trading volumes are more likely to occur following large price returns, and the comovement between trading volumes and price returns is more pronounced for large trading volumes.

Liquid hyperpolarized 129Xe produced by phase exchange in a convection cell

NASA Astrophysics Data System (ADS)

Su, T.; Samuelson, G. L.; Morgan, S. W.; Laicher, G.; Saam, B.

2004-09-01

We present a method for the production of liquid hyperpolarized Xe129 that employs spin-exchange optical pumping in the gas phase and subsequent phase exchange with a column of xenon liquid. A convection loop inside the sealed glass cell allows efficient transfer of magnetization between the gas and liquid phases. By condensing to liquid a large fraction of the sample, this scheme permits the polarization of many more Xe129 atoms in a given sealed-cell volume than would otherwise be possible. We have thus far produced a steady-state polarization of 8% in 0.1mL of liquid with a characteristic rise time of ≈15min.

Molar volume and adsorption isotherm dependence of capillary forces in nanoasperity contacts.

PubMed

Asay, David B; Kim, Seong H

2007-11-20

The magnitude of the capillary force at any given temperature and adsorbate partial pressure depends primarily on four factors: the surface tension of the adsorbate, its liquid molar volume, its isothermal behavior, and the contact geometry. At large contacting radii, the adsorbate surface tension and the contact geometry are dominating. This is the case of surface force apparatus measurements and atomic force microscopy (AFM) experiments with micrometer-size spheres. However, as the size of contacting asperities decreases to the nanoscale as in AFM experiments with sharp tips, the molar volume and isotherm of the adsorbate become very important to capillary formation as well as capillary adhesion. This effect is experimentally and theoretically explored with simple alcohol molecules (ethanol, 1-butanol, and 1-pentanol) which have comparable surface tensions but differing liquid molar volumes. Adsorption isotherms for these alcohols on silicon oxide are also reported.

75 FR 62112 - Notice of Availability of a Broad Spectrum of Patents for Exclusive, Partially Exclusive, or Non...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-07

... Systems and methods for collecting particles from a large volume of gas into a small volume of liquid...,797 Use of current channeling in multiple node laser systems and methods thereof. Conroy 7,650,710...,749 Systems and methods for analyzing acoustic waves. Darwish 7,655,944 Systems and methods for...

On canonical cylinder sections for accurate determination of contact angle in microgravity

NASA Technical Reports Server (NTRS)

Concus, Paul; Finn, Robert; Zabihi, Farhad

1992-01-01

Large shifts of liquid arising from small changes in certain container shapes in zero gravity can be used as a basis for accurately determining contact angle. Canonical geometries for this purpose, recently developed mathematically, are investigated here computationally. It is found that the desired nearly-discontinuous behavior can be obtained and that the shifts of liquid have sufficient volume to be readily observed.

Liquid injectable silicone: a review of its history, immunology, technical considerations, complications, and potential.

PubMed

Narins, Rhoda S; Beer, Kenneth

2006-09-01

For over five decades, liquid injectable silicone has been used for soft-tissue augmentation. Its use has engendered polarized reactions from the public and from physicians. Adherents of this product tout its inert chemical structure, ease of use, and low cost. Opponents of silicone cite the many reports of complications, including granulomas, pneumonitis, and disfiguring nodules that are usually the result of large-volume injection and/or industrial grade or adulterated material. Unfortunately, as recently as 2006, reports in The New England Journal of Medicine and The New York Times failed to distinguish between the use of medical grade silicone injected by physicians trained in the microdroplet technique and the use of large volumes of industrial grade products injected by unlicensed or unskilled practitioners. This review separates these two markedly different procedures. In addition, it provides an overview of the chemical structure of liquid injectable silicone, the immunology of silicone reactions within the body, treatment for cosmetic improvement including human immunodeficiency virus lipoatrophy, technical considerations for its injection, complications seen following injections, and some considerations of the future for silicone soft-tissue augmentation.

Partial molar volume of n-alcohols at infinite dilution in water calculated by means of scaled particle theory.

PubMed

Graziano, Giuseppe

2006-04-07

The partial molar volume of n-alcohols at infinite dilution in water is smaller than the molar volume in the neat liquid phase. It is shown that the formula for the partial molar volume at infinite dilution obtained from the scaled particle theory equation of state for binary hard sphere mixtures is able to reproduce in a satisfactory manner the experimental data over a large temperature range. This finding implies that the packing effects play the fundamental role in determining the partial molar volume at infinite dilution in water also for solutes, such as n-alcohols, forming H bonds with water molecules. Since the packing effects in water are largely related to the small size of its molecules, the latter feature is the ultimate cause of the decrease in partial molar volume associated with the hydrophobic effect.

Large-volume injection of sample diluents not miscible with the mobile phase as an alternative approach in sample preparation for bioanalysis: an application for fenspiride bioequivalence.

PubMed

Medvedovici, Andrei; Udrescu, Stefan; Albu, Florin; Tache, Florentin; David, Victor

2011-09-01

Liquid-liquid extraction of target compounds from biological matrices followed by the injection of a large volume from the organic layer into the chromatographic column operated under reversed-phase (RP) conditions would successfully combine the selectivity and the straightforward character of the procedure in order to enhance sensitivity, compared with the usual approach of involving solvent evaporation and residue re-dissolution. Large-volume injection of samples in diluents that are not miscible with the mobile phase was recently introduced in chromatographic practice. The risk of random errors produced during the manipulation of samples is also substantially reduced. A bioanalytical method designed for the bioequivalence of fenspiride containing pharmaceutical formulations was based on a sample preparation procedure involving extraction of the target analyte and the internal standard (trimetazidine) from alkalinized plasma samples in 1-octanol. A volume of 75 µl from the octanol layer was directly injected on a Zorbax SB C18 Rapid Resolution, 50 mm length × 4.6 mm internal diameter × 1.8 µm particle size column, with the RP separation being carried out under gradient elution conditions. Detection was made through positive ESI and MS/MS. Aspects related to method development and validation are discussed. The bioanalytical method was successfully applied to assess bioequivalence of a modified release pharmaceutical formulation containing 80 mg fenspiride hydrochloride during two different studies carried out as single-dose administration under fasting and fed conditions (four arms), and multiple doses administration, respectively. The quality attributes assigned to the bioanalytical method, as resulting from its application to the bioequivalence studies, are highlighted and fully demonstrate that sample preparation based on large-volume injection of immiscible diluents has an increased potential for application in bioanalysis.

Measuring the structure factor of simple fluids under extreme conditions

NASA Astrophysics Data System (ADS)

Weck, Gunnar

2013-06-01

The structure and dynamics of fluids, although a long standing matter of investigations, is still far from being well established. In particular, with the existence of a first order liquid-liquid phase transition (LLT) discovered in liquid phosphorus at 0.9 GPa and 1300 K it is now recognized that the fluid state could present complex structural changes. At present, very few examples of LLTs have been clearly evidenced, which may mean that a larger range of densities must be probed. First order transitions between a molecular and a polymeric liquid have been recently predicted by first principles calculations in liquid nitrogen at 88 GPa and 2000 K and in liquid CO2 at 45 GPa and 1850 K. The only device capable of reaching these extreme conditions is the diamond anvil cell (DAC), in which, the sample is sandwiched between two diamond anvils of thickness 100 times larger. Consequently, the diffracted signal from the sample is very weak compared to the Compton signal of the anvils, and becomes hardly measurable for pressures above ~20 GPa. A similar problem has been faced by the high pressure community using large volume press so as to drastically reduce the x-ray background from the sample environment. In the angle-dispersive diffraction configuration, it was proposed to use a multichannel collimator (MCC). This solution has been implemented to fit the constraints of the Paris-Edimburg (PE) large volume press and it is now routinely used on beamline ID27 of the European Synchrotron Radiation Facility. In this contribution, we present our adaptation of the MCC device accessible at ID27 for the DAC experiment. Because of the small sample volume a careful alignment procedure between the MCC slits and the DAC had to be implemented. The data analysis procedure initially developed by Eggert et al. has also been completed in order to take into account the complex contribution of the MCC slits. A large reduction of the Compton diffusion from the diamond anvils is obtained enabling quantitative structure factor measurement, even for the weakest x-ray scatterer liquid. Experimental results on fluid hydrogen will be presented to test the limits of this new setup. In collaboration with Gaston Garbarino, ESRF, France; Frederic Datchi, Sandra Ninet, Université Pierre et Marie Curie-Paris VI, France; Dylan Spaulding, Paul Loubeyre, CEA, DAM, DIF, France; and Mohamed Mezouar, ESRF, France.

Electrochemical attosyringe.

PubMed

Laforge, François O; Carpino, James; Rotenberg, Susan A; Mirkin, Michael V

2007-07-17

The ability to manipulate ultrasmall volumes of liquids is essential in such diverse fields as cell biology, microfluidics, capillary chromatography, and nanolithography. In cell biology, it is often necessary to inject material of high molecular weight (e.g., DNA, proteins) into living cells because their membranes are impermeable to such molecules. All techniques currently used for microinjection are plagued by two common problems: the relatively large injector size and volume of injected fluid, and poor control of the amount of injected material. Here we demonstrate the possibility of electrochemical control of the fluid motion that allows one to sample and dispense attoliter-to-picoliter (10(-18) to 10(-12) liter) volumes of either aqueous or nonaqueous solutions. By changing the voltage applied across the liquid/liquid interface, one can produce a sufficient force to draw solution inside a nanopipette and then inject it into an immobilized biological cell. A high success rate was achieved in injections of fluorescent dyes into cultured human breast cells. The injection of femtoliter-range volumes can be monitored by video microscopy, and current/resistance-based approaches can be used to control injections from very small pipettes. Other potential applications of the electrochemical syringe include fluid dispensing in nanolithography and pumping in microfluidic systems.

Electrochemical attosyringe

PubMed Central

Laforge, François O.; Carpino, James; Rotenberg, Susan A.; Mirkin, Michael V.

2007-01-01

The ability to manipulate ultrasmall volumes of liquids is essential in such diverse fields as cell biology, microfluidics, capillary chromatography, and nanolithography. In cell biology, it is often necessary to inject material of high molecular weight (e.g., DNA, proteins) into living cells because their membranes are impermeable to such molecules. All techniques currently used for microinjection are plagued by two common problems: the relatively large injector size and volume of injected fluid, and poor control of the amount of injected material. Here we demonstrate the possibility of electrochemical control of the fluid motion that allows one to sample and dispense attoliter-to-picoliter (10−18 to 10−12 liter) volumes of either aqueous or nonaqueous solutions. By changing the voltage applied across the liquid/liquid interface, one can produce a sufficient force to draw solution inside a nanopipette and then inject it into an immobilized biological cell. A high success rate was achieved in injections of fluorescent dyes into cultured human breast cells. The injection of femtoliter-range volumes can be monitored by video microscopy, and current/resistance-based approaches can be used to control injections from very small pipettes. Other potential applications of the electrochemical syringe include fluid dispensing in nanolithography and pumping in microfluidic systems. PMID:17620612

On demand manufacturing of patient-specific liquid capsules via co-ordinated 3D printing and liquid dispensing.

PubMed

Okwuosa, Tochukwu C; Soares, Cindy; Gollwitzer, Verena; Habashy, Rober; Timmins, Peter; Alhnan, Mohamed A

2018-06-15

A method for the production of liquid capsules with the potential of modifying drug dose and release is presented. For the first time, the co-ordinated use of fused deposition modelling (FDM), 3D printing and liquid dispensing to fabricate individualised dosage form on demand in a fully automated fashion has been demonstrated. Polymethacrylate shells (Eudragit EPO and RL) for immediate and extended release were fabricated using FDM 3D printing and simultaneously filled using a computer-controlled liquid dispenser loaded with model drug solution (theophylline) or suspension (dipyridamole). The impact of printing modes: simultaneous shell printing and filling (single-phase) or sequential 3D printing of shell bottom, filling and shell cap (multi-phase), nozzle size, syringe volume, and shell structure has been reported. The use of shell thickness of 1.6 mm, and concentric architecture allowed successful containment of liquid core whilst maintaining the release properties of the 3D printed liquid capsule. The linear relationship between the theoretical and the actual volumes from the dispenser reflected its potential for accurate dosing (R 2  = 0.9985). Modifying the shell thickness of Eudragit RL capsule allowed a controlled extended drug release without the need for formulation change. Owing to its low cost and versatility, this approach can be adapted to wide spectrum of liquid formulations such as small and large molecule solutions and obviate the need for compatibility with the high temperature of FDM 3D printing process. In a clinical setting, health care staff will be able to instantly manufacture in small volumes liquid capsules with individualised dose contents and release pattern in response to specific patient's needs. Copyright © 2018 Elsevier B.V. All rights reserved.

Correlation of the fragility of metallic liquids with the high temperature structure, volume, and cohesive energy

NASA Astrophysics Data System (ADS)

Gangopadhyay, A. K.; Pueblo, C. E.; Dai, R.; Johnson, M. L.; Ashcraft, R.; Van Hoesen, D.; Sellers, M.; Kelton, K. F.

2017-04-01

The thermal expansion coefficients, structure factors, and viscosities of twenty-five equilibrium and supercooled metallic liquids have been measured using an electrostatic levitation (ESL) facility. The structure factor was measured at the Advanced Photon Source, Argonne, using the ESL. A clear connection between liquid fragility and structural and volumetric changes at high temperatures is established; the observed changes are larger for the more fragile liquids. It is also demonstrated that the fragility of metallic liquids is determined to a large extent by the cohesive energy and is, therefore, predictable. These results are expected to provide useful guidance in the future design of metallic glasses.

HOW DOES ADDING AND REMOVING LIQUID FROM SOCKET BLADDERS AFFECT RESIDUAL LIMB FLUID VOLUME?

PubMed Central

Sanders, JE; Cagle, JC; Harrison, DS; Myers, TR; Allyn, KJ

2015-01-01

Adding and removing liquid from socket bladders is a means for people with limb loss to accommodate residual limb volume change. Nineteen people with trans-tibial amputation using their regular prosthetic socket fitted with fluid bladders on the inside socket surface underwent cycles of bladder liquid addition and removal. In each cycle, subjects sat, stood, and walked for 90s with bladder liquid added and then sat, stood, and walking for 90s again with the bladder liquid removed. The amount of bladder liquid added was increased in each cycle. Bioimpedance analysis was implemented to measure residual limb fluid volume. Results showed that the preferred bladder liquid volume was 16.8 mL (s.d.8.4), corresponding to 1.7% (s.d.0.8%) of the average socket volume between the bioimpedance voltage-sensing electrodes. Limb fluid volume driven out of the residual limb when bladder liquid was added was typically not recovered upon subsequent bladder liquid removal. Fifteen of nineteen subjects experienced a gradual limb fluid volume loss over the test session. Care should be taken when implementing adjustable socket technologies in people with limb amputation. Reducing socket volume may accentuate limb fluid volume loss. PMID:24203546

Electromagnetic liquid pistons for capillarity-based pumping

NASA Astrophysics Data System (ADS)

Malouin, Bernard; Olles, Joseph; Cheng, Lili; Hirsa, Amir; Vogel, Michael

2011-11-01

Two adjoining ferrofluid droplets can behave as an electronically-controlled oscillator or switch by an appropriate balance of magnetic, capillary, and inertial forces. Their motion can be exploited to displace a surrounding liquid, forming electromagnetic liquid pistons. Such ferrofluid pistons can pump a precise volume of liquid via finely tunable amplitudes or resonant frequencies with no solid moving parts. Here we demonstrate the use of these liquid pistons in capillarity-dominated systems for variable focal distance liquid lenses with nearly perfect spherical interfaces. These liquid/liquid lenses feature many promising qualities not previously realized together in a liquid lens, including large apertures, immunity to evaporation, invariance to orientation relative to gravity, and low driving voltages. The dynamics of these liquid pistons is examined, with experimental measurements showing good agreement with a spherical cap model. A centimeter-scale lens was shown to respond in excess of 30 Hz, with resonant frequencies over 1 kHz predicted for scaled down systems.

Research on volume metrology method of large vertical energy storage tank based on internal electro-optical distance-ranging method

NASA Astrophysics Data System (ADS)

Hao, Huadong; Shi, Haolei; Yi, Pengju; Liu, Ying; Li, Cunjun; Li, Shuguang

2018-01-01

A Volume Metrology method based on Internal Electro-optical Distance-ranging method is established for large vertical energy storage tank. After analyzing the vertical tank volume calculation mathematical model, the key processing algorithms, such as gross error elimination, filtering, streamline, and radius calculation are studied for the point cloud data. The corresponding volume values are automatically calculated in the different liquids by calculating the cross-sectional area along the horizontal direction and integrating from vertical direction. To design the comparison system, a vertical tank which the nominal capacity is 20,000 m3 is selected as the research object, and there are shown that the method has good repeatability and reproducibility. Through using the conventional capacity measurement method as reference, the relative deviation of calculated volume is less than 0.1%, meeting the measurement requirements. And the feasibility and effectiveness are demonstrated.

High air volume to low liquid volume aerosol collector

DOEpatents

Masquelier, Donald A.; Milanovich, Fred P.; Willeke, Klaus

2003-01-01

A high air volume to low liquid volume aerosol collector. A high volume flow of aerosol particles is drawn into an annular, centripetal slot in a collector which directs the aerosol flow into a small volume of liquid pool contained is a lower center section of the collector. The annular jet of air impinges into the liquid, imbedding initially airborne particles in the liquid. The liquid in the pool continuously circulates in the lower section of the collector by moving to the center line, then upwardly, and through assistance by a rotating deflector plate passes back into the liquid at the outer area adjacent the impinging air jet which passes upwardly through the liquid pool and through a hollow center of the collector, and is discharged via a side outlet opening. Any liquid droplets escaping with the effluent air are captured by a rotating mist eliminator and moved back toward the liquid pool. The collector includes a sensor assembly for determining, controlling, and maintaining the level of the liquid pool, and includes a lower centrally located valve assembly connected to a liquid reservoir and to an analyzer for analyzing the particles which are impinged into the liquid pool.

40 CFR 799.2155 - Commercial hexane.

Code of Federal Regulations, 2013 CFR

2013-07-01

... least 40 liquid volume percent n-hexane (CAS No. 110-54-3) and at least 5 liquid volume percent... contains at least 40 liquid volume percent but no more than 55 liquid volume percent n-hexane and no less... 40 Protection of Environment 33 2013-07-01 2013-07-01 false Commercial hexane. 799.2155 Section...

40 CFR 799.2155 - Commercial hexane.

Code of Federal Regulations, 2014 CFR

2014-07-01

... least 40 liquid volume percent n-hexane (CAS No. 110-54-3) and at least 5 liquid volume percent... contains at least 40 liquid volume percent but no more than 55 liquid volume percent n-hexane and no less... 40 Protection of Environment 32 2014-07-01 2014-07-01 false Commercial hexane. 799.2155 Section...

Communication: Unusual structure and transport in ionic liquid-hexane mixtures

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

Liang, Min; Khatun, Sufia; Castner, Edward W., E-mail: ecastner@rci.rutgers.edu

2015-03-28

Ionic liquids having a sufficiently amphiphilic cation can dissolve large volume fractions of alkanes, leading to mixtures with intriguing properties on molecular length scales. The trihexyl(tetradecyl)phosphonium cation paired with the bis(trifluoromethylsulfonyl)amide anion provides an ionic liquid that can dissolve large mole fractions of hexane. We present experimental results on mixtures of n-C{sub 6}D{sub 14} with this ionic liquid. High-energy X-ray scattering studies reveal a persistence of the characteristic features of ionic liquid structure even for 80% dilution with n-C{sub 6}D{sub 14}. Nuclear magnetic resonance self-diffusion results reveal decidedly non-hydrodynamic behavior where the self-diffusion of the neutral, non-polar n-C{sub 6}D{sub 14}more » is on average a factor of 21 times faster than for the cation. Exploitation of the unique structural and transport properties of these mixtures may lead to new opportunities for designer solvents for enhanced chemical reactivity and interface science.« less

Spectral mass gauging of unsettled liquid with acoustic waves

NASA Astrophysics Data System (ADS)

Feller, Jeffrey; Kashani, Ali; Khasin, Michael; Muratov, Cyrill; Osipov, Viatcheslav; Sharma, Surendra

2017-12-01

Propellant mass gauging is one of the key technologies required to enable the next step in NASA’s space exploration program. At present, there is no reliable method to accurately measure the amount of unsettled liquid propellant in a large-scale propellant tank in micro- or zero gravity. Recently we proposed a new approach to use sound waves to probe the resonance frequencies of the two-phase liquid-gas mixture and take advantage of the mathematical properties of the high frequency spectral asymptotics to determine the volume fraction of the tank filled with liquid. We report the current progress in exploring the feasibility of this approach in the case of large propellant tanks, both experimental and theoretical. Excitation and detection procedures using solenoids for excitation and both hydrophones and accelerometers for detection have been developed. A 3% uncertainty for mass-gauging was demonstrated for a 200-liter tank partially filled with liquid for various unsettled configurations, such as tilts and artificial ullages.

Communication: Unusual structure and transport in ionic liquid-hexane mixtures

DOE PAGES

Liang, Min; Khatun, Sufia; Castner, Edward W.

2015-03-28

Ionic liquids having a sufficiently amphiphilic cation can dissolve large volume fractions of alkanes, leading to mixtures with intriguing properties on molecular length scales. The trihexyl(tetradecyl)phosphonium cation paired with the bis(trifluoromethylsulfonyl)amide anion provides an ionic liquid that can dissolve large mole fractions of hexane. We present experimental results on mixtures of n-C 6D 14 with this ionic liquid. High- energy X-ray scattering studies reveal a persistence of the characteristic features of ionic liquid structure even for 80% dilution with n-C 6D 14. NMR self-diffusion results reveal decidedly non-hydrodynamic behavior where the self-diffusion of the neutral, non-polar n-C 6D 14 ismore » on average a factor of 21 times faster than for the cation. Exploitation of the unique structural and transport properties of these mixtures may lead to new opportunities for designer solvents for enhanced chemical reactivity and interface science.« less

Numerical Investigation on Sensitivity of Liquid Jet Breakup to Physical Fuel Properties with Experimental Comparison

NASA Astrophysics Data System (ADS)

Kim, Dokyun; Bravo, Luis; Matusik, Katarzyna; Duke, Daniel; Kastengren, Alan; Swantek, Andy; Powell, Christopher; Ham, Frank

2016-11-01

One of the major concerns in modern direct injection engines is the sensitivity of engine performance to fuel characteristics. Recent works have shown that even slight differences in fuel properties can cause significant changes in efficiency and emission of an engine. Since the combustion process is very sensitive to the fuel/air mixture formation resulting from disintegration of liquid jet, the precise assessment of fuel sensitivity on liquid jet atomization process is required first to study the impact of different fuels on the combustion. In the present study, the breaking process of a liquid jet from a diesel injector injecting into a quiescent gas chamber is investigated numerically and experimentally for different liquid fuels (n-dodecane, iso-octane, CAT A2 and C3). The unsplit geometric Volume-of-Fluid method is employed to capture the phase interface in Large-eddy simulations and results are compared against the radiography measurement from Argonne National Lab including jet penetration, liquid mass distribution and volume fraction. The breakup characteristics will be shown for different fuels as well as droplet PDF statistics to demonstrate the influences of the physical properties on the primary atomization of liquid jet. Supported by HPCMP FRONTIER award, US DOD, Office of the Army.

Toward comprehensive studies of liquids at high pressures and high temperatures: Combined structure, elastic wave velocity, and viscosity measurements in the Paris-Edinburgh cell

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

Kono, Yoshio; Park, Changyong; Kenney-Benson, Curtis

2014-08-19

Techniques for measuring liquid structure, elastic wave velocity, and viscosity under high pressure have been integrated using a Paris–Edinburgh cell at Beamline 16-BM-B, HPCAT of the Advanced Photon Source. The Paris–Edinburgh press allows for compressing large volume samples (up to 2 mm in both diameter and length) up to ~7 GPa and 2000 °C. Multi-angle energy dispersive X-ray diffraction provides structure factors of liquid to a large Q of ~19 Å. Ultrasonic techniques have been developed to investigate elastic wave velocity of liquids combined with the X-ray imaging. Falling sphere viscometry, using high-speed X-ray radiography (>1000 frames/s), enables us tomore » investigate a wide range of viscosity, from those of high viscosity silicates or oxides melts to low viscosity (<1 mPa s) liquids and fluids such as liquid metals or salts. The integration of these multiple techniques has promoted comprehensive studies of structure and physical properties of liquids as well as amorphous materials at high pressures and high temperatures, making it possible to investigate correlations between structure and physical properties of liquids in situ.« less

High-pressure Experimental Studies on Geo-liquids Using Synchrotron Radiation at the Advanced Photon Source

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

Wang, Yanbin; Shen, Guoyin

2014-12-23

Here, we review recent progress in studying silicate, carbonate, and metallic liquids of geological and geophysical importance at high pressure and temperature, using the large-volume high-pressure devices at the third-generation synchrotron facility of the Advanced Photon Source, Argonne National Laboratory. These integrated high-pressure facilities now offer a unique combination of experimental techniques that allow researchers to investigate structure, density, elasticity, viscosity, and interfacial tension of geo-liquids under high pressure, in a coordinated and systematic fashion. Moreover, we describe experimental techniques, along with scientific highlights. Future developments are also discussed.

Structure and phase behavior of a confined nanodroplet composed of the flexible chain molecules.

PubMed

Kim, Soon-Chul; Kim, Eun-Young; Seong, Baek-Seok

2011-04-28

A polymer density functional theory has been employed for investigating the structure and phase behaviors of the chain polymer, which is modelled as the tangentially connected sphere chain with an attractive interaction, inside the nanosized pores. The excess free energy of the chain polymer has been approximated as the modified fundamental measure-theory for the hard spheres, the Wertheim's first-order perturbation for the chain connectivity, and the mean-field approximation for the van der Waals contribution. For the value of the chemical potential corresponding to a stable liquid phase in the bulk system and a metastable vapor phase, the flexible chain molecules undergo the liquid-vapor transition as the pore size is reduced; the vapor is the stable phase at small volume, whereas the liquid is the stable phase at large volume. The wide liquid-vapor coexistence curve, which explains the wide range of metastable liquid-vapor states, is observed at low temperature. The increase of temperature and decrease of pore size result in a narrowing of liquid-vapor coexistence curves. The increase of chain length leads to a shift of the liquid-vapor coexistence curve towards lower values of chemical potential. The coexistence curves for the confined phase diagram are contained within the corresponding bulk liquid-vapor coexistence curve. The equilibrium capillary phase transition occurs at a higher chemical potential than in the bulk phase.

The Partial Molar Volume and Compressibility of the FeO Component in Model Basalts (Mixed CaAl2Si2O8-CaMgSi2O6-CaFeSi2O6 Liquids) at 0 GPa: evidence of Fe2+ in 6-fold coordination

NASA Astrophysics Data System (ADS)

Guo, X.; Lange, R. A.; Ai, Y.

2010-12-01

FeO is an important component in magmatic liquids and yet its partial molar volume at one bar is not as well known as that for Fe2O3 because of the difficulty of performing double-bob density measurements under reducing conditions. Moreover, there is growing evidence from spectroscopic studies that Fe2+ occurs in 4, 5, and 6-fold coordination in silicate melts, and it is expected that the partial molar volume and compressibility of the FeO component will vary accordingly. We have conducted both density and relaxed sound speed measurements on four liquids in the An-Di-Hd (CaAl2Si2O8-CaMgSi2O6-CaFeSi2O6) system: (1) Di-Hd (50:50), (2) An-Hd (50:50), (3) An-Di-Hd (33:33:33) and (4) Hd (100). Densities were measured between 1573 and 1838 K at one bar with the double-bob Archimedean method using molybdenum bobs and crucibles in a reducing gas (1%CO-99%Ar) environment. The sound speeds were measured under similar conditions with a frequency-sweep acoustic interferometer, and used to calculate isothermal compressibility. All the density data for the three multi-component (model basalt) liquids were combined with density data on SiO2-Al2O3-CaO-MgO-K2O-Na2O liquids (Lange, 1997) in a fit to a linear volume equation; the results lead to a partial molar volume (±1σ) for FeO =11.7 ± 0.3(±1σ) cm3/mol at 1723 K. This value is similar to that for crystalline FeO at 298 K (halite structure; 12.06 cm3/mol), which suggests an average Fe2+ coordination of ~6 in these model basalt compositions. In contrast, the fitted partial molar volume of FeO in pure hedenbergite liquid is 14.6 ± 0.3 at 1723 K, which is consistent with an average Fe2+ coordination of 4.3 derived from EXAFS spectroscopy (Rossano, 2000). Similarly, all the compressibility data for the three multi-component liquids were combined with compressibility data on SiO2-Al2O3-CaO-MgO liquids (Ai and Lange, 2008) in a fit to an ideal mixing model for melt compressibility; the results lead to a partial molar compressibility (±1σ) for FeO = 2.4 (± 0.3) 10-2 GPa-1 at 1723 K. In contrast, the compressibility of FeO in pure hedenbergite liquid is more than twice as large: 6.3 (± 0.2) 10-2 GPa-1. When these results are combined with density and sound speed data on CaO-FeO-SiO2 liquids at one bar (Guo et al., 2009), a systematic and linear variation between the partial molar volume and compressibility of the FeO component is obtained, which appears to track changes in the average Fe2+ coordination in these liquids. Therefore, the three most important conclusions of this study are: (1) ideal mixing of volume and compressibility does not occur for all FeO-bearing magmatic liquids, owing to changes in Fe2+ coordination, (2) the partial molar volume and compressibility of FeO varies linearly and systematically with Fe2+ coordination, and (3) ideal mixing of volume and compressibility does occur among the three mixed An-Di-Hd liquids, presumably because of a common, average Fe2+ coordination of ~6.

Optical scattering lengths in large liquid-scintillator neutrino detectors.

PubMed

Wurm, M; von Feilitzsch, F; Göger-Neff, M; Hofmann, M; Lachenmaier, T; Lewke, T; Marrodán Undagoitia, T; Meindl, Q; Möllenberg, R; Oberauer, L; Potzel, W; Tippmann, M; Todor, S; Traunsteiner, C; Winter, J

2010-05-01

For liquid-scintillator neutrino detectors of kiloton scale, the transparency of the organic solvent is of central importance. The present paper reports on laboratory measurements of the optical scattering lengths of the organic solvents phenylxylylethane, linear alkylbenzene (LAB), and dodecane, which are under discussion for next-generation experiments such as SNO+ (Sudbury Neutrino Observatory), HanoHano, or LENA (Low Energy Neutrino Astronomy). Results comprise the wavelength range of 415-440 nm. The contributions from Rayleigh and Mie scattering as well as from absorption/re-emission processes are discussed. Based on the present results, LAB seems to be the preferred solvent for a large-volume detector.

Optical scattering lengths in large liquid-scintillator neutrino detectors

NASA Astrophysics Data System (ADS)

Wurm, M.; von Feilitzsch, F.; Göger-Neff, M.; Hofmann, M.; Lachenmaier, T.; Lewke, T.; Undagoitia, T. Marrodán; Meindl, Q.; Möllenberg, R.; Oberauer, L.; Potzel, W.; Tippmann, M.; Todor, S.; Traunsteiner, C.; Winter, J.

2010-05-01

For liquid-scintillator neutrino detectors of kiloton scale, the transparency of the organic solvent is of central importance. The present paper reports on laboratory measurements of the optical scattering lengths of the organic solvents phenylxylylethane, linear alkylbenzene (LAB), and dodecane, which are under discussion for next-generation experiments such as SNO+ (Sudbury Neutrino Observatory), HanoHano, or LENA (Low Energy Neutrino Astronomy). Results comprise the wavelength range of 415-440 nm. The contributions from Rayleigh and Mie scattering as well as from absorption/re-emission processes are discussed. Based on the present results, LAB seems to be the preferred solvent for a large-volume detector.

Shock wave absorber having apertured plate

DOEpatents

Shin, Y.W.; Wiedermann, A.H.; Ockert, C.E.

1983-08-26

The shock or energy absorber disclosed herein utilizes an apertured plate maintained under the normal level of liquid flowing in a piping system and disposed between the normal liquid flow path and a cavity pressurized with a compressible gas. The degree of openness (or porosity) of the plate is between 0.01 and 0.60. The energy level of a shock wave travelling down the piping system thus is dissipated by some of the liquid being jetted through the apertured plate toward the cavity. The cavity is large compared to the quantity of liquid jetted through the apertured plate, so there is little change in its volume. The porosity of the apertured plate influences the percentage of energy absorbed.

Shock wave absorber having apertured plate

DOEpatents

Shin, Yong W.; Wiedermann, Arne H.; Ockert, Carl E.

1985-01-01

The shock or energy absorber disclosed herein utilizes an apertured plate maintained under the normal level of liquid flowing in a piping system and disposed between the normal liquid flow path and a cavity pressurized with a compressible gas. The degree of openness (or porosity) of the plate is between 0.01 and 0.60. The energy level of a shock wave travelling down the piping system thus is dissipated by some of the liquid being jetted through the apertured plate toward the cavity. The cavity is large compared to the quantity of liquid jetted through the apertured plate, so there is little change in its volume. The porosity of the apertured plate influences the percentage of energy absorbed.

Branched Rod-Coil Polyimide-Poly(Alkylene Oxide) Copolymers and Electrolyte Compositions

NASA Technical Reports Server (NTRS)

Meador, Maryann B. (Inventor); Tigelaar, Dean M. (Inventor)

2014-01-01

Crosslinked polyimide-poly(alkylene oxide) copolymers capable of holding large volumes of liquid while maintaining good dimensional stability. Copolymers are derived at ambient temperatures from amine endcapped amic-acid oligomers subsequently imidized in solution at increased temperatures, followed by reaction with trifunctional compounds in the presence of various additives. Films of these copolymers hold over four times their weight at room temperature of liquids such as ionic liquids (RTIL) and/or carbonate solvents. These rod-coil polyimide copolymers are used to prepare polymeric electrolytes by adding to the copolymers various amounts of compounds such as ionic liquids (RTIL), lithium trifluoromethane-sulfonimide (LiTFSi) or other lithium salts, and alumina.

Reliable determination of oxygen and hydrogen isotope ratios in atmospheric water vapour adsorbed on 3A molecular sieve.

PubMed

Han, Liang-Feng; Gröning, Manfred; Aggarwal, Pradeep; Helliker, Brent R

2006-01-01

The isotope ratio of atmospheric water vapour is determined by wide-ranging feedback effects from the isotope ratio of water in biological water pools, soil surface horizons, open water bodies and precipitation. Accurate determination of atmospheric water vapour isotope ratios is important for a broad range of research areas from leaf-scale to global-scale isotope studies. In spite of the importance of stable isotopic measurements of atmospheric water vapour, there is a paucity of published data available, largely because of the requirement for liquid nitrogen or dry ice for quantitative trapping of water vapour. We report results from a non-cryogenic method for quantitatively trapping atmospheric water vapour using 3A molecular sieve, although water is removed from the column using standard cryogenic methods. The molecular sieve column was conditioned with water of a known isotope ratio to 'set' the background signature of the molecular sieve. Two separate prototypes were developed, one for large collection volumes (3 mL) and one for small collection volumes (90 microL). Atmospheric water vapour was adsorbed to the column by pulling air through the column for several days to reach the desired final volume. Water was recovered from the column by baking at 250 degrees C in a dry helium or nitrogen air stream and cryogenically trapped. For the large-volume apparatus, the recovered water differed from water that was simultaneously trapped by liquid nitrogen (the experimental control) by 2.6 per thousand with a standard deviation (SD) of 1.5 per thousand for delta(2)H and by 0.3 per thousand with a SD of 0.2 per thousand for delta(18)O. Water-vapour recovery was not satisfactory for the small volume apparatus. Copyright (c) 2006 John Wiley & Sons, Ltd.

SELECTIVE TRACE ENRICHMENT BY IMMUNOAFFINITY CAPILLARY ELECTROCHROMATOGRAPHY ON-LINE WITH CAPILLARY ZONE ELECTROPHORESIS - LASER-INDUCED FLUORESCENCE

EPA Science Inventory

Limited by the lack of a sensitive, universal detector, many capillary-based liquid-phase separation techniques might benefit from techniques that overcome modest concentration sensitivity by preconcentrating large injection volumes. The work presented employs selective solid-ph...

Electrical Signatures of Ethanol-Liquid Mixtures: Implications for Monitoring Biofuels Migration in the Subsurface

EPA Science Inventory

Ethanol (EtOH), an emerging contaminant with potential direct and indirect environmental effects, poses threats to water supplies when spilled in large volumes. A series of experiments was directed at understanding the electrical geophysical signatures arising from groundwater co...

SPREADING LAGOONED SEWAGE SLUDGE ON FARMLAND: A CASE HISTORY

EPA Science Inventory

This project demonstrated that land application is feasible and practical for a metropolitan treatment plant for disposal of a large volume (265,000 cu m) of stabilized, liquid sewage sludge stored in lagoons. The project involved transportation of sludge by semi-trailer tankers ...

A method of measuring a molten metal liquid pool volume

DOEpatents

Garcia, G.V.; Carlson, N.M., Donaldson, A.D.

1990-12-12

A method of measuring a molten metal liquid pool volume and in particular molten titanium liquid pools, including the steps of (a) generating an ultrasonic wave at the surface of the molten metal liquid pool, (b) shining a light on the surface of a molten metal liquid pool, (c) detecting a change in the frequency of light, (d) detecting an ultrasonic wave echo at the surface of the molten metal liquid pool, and (e) computing the volume of the molten metal liquid. 3 figs.

Method of measuring a liquid pool volume

DOEpatents

Garcia, G.V.; Carlson, N.M.; Donaldson, A.D.

1991-03-19

A method of measuring a molten metal liquid pool volume and in particular molten titanium liquid pools is disclosed, including the steps of (a) generating an ultrasonic wave at the surface of the molten metal liquid pool, (b) shining a light on the surface of a molten metal liquid pool, (c) detecting a change in the frequency of light, (d) detecting an ultrasonic wave echo at the surface of the molten metal liquid pool, and (e) computing the volume of the molten metal liquid. 3 figures.

Method of measuring a liquid pool volume

DOEpatents

Garcia, Gabe V.; Carlson, Nancy M.; Donaldson, Alan D.

1991-01-01

A method of measuring a molten metal liquid pool volume and in particular molten titanium liquid pools, including the steps of (a) generating an ultrasonic wave at the surface of the molten metal liquid pool, (b) shining a light on the surface of a molten metal liquid pool, (c) detecting a change in the frequency of light, (d) detecting an ultrasonic wave echo at the surface of the molten metal liquid pool, and (e) computing the volume of the molten metal liquid.

Computational comparison of high and low viscosity micro-scale droplets splashing on a dry surface

NASA Astrophysics Data System (ADS)

Boelens, Arnout; Latka, Andrzej; de Pablo, Juan

2015-11-01

Depending on viscosity, a droplet splashing on a dry surface can splash immediately upon impact, a so called prompt splash, or after initially spreading on the surface, a late splash. One of the open questions in splashing is whether the mechanism behind both kinds of splashing is the same or not. Simulation results are presented comparing splashing of low viscosity ethanol with high viscosity silicone oil in air. The droplets are several hundred microns large. The simulations are 2D, and are performed using a Volume Of Fluid approach with a Finite Volume technique. The contact line is described using the Generalized Navier Boundary Condition. Both the gas phase and the liquid phase are assumed to be incompressible. The results of the simulations show good agreement with experiments. Observations that are reproduced include the effect of reduced ambient pressure suppressing splashing, and the details of liquid sheet formation and breakup. While the liquid sheet ejected in an early splash breaks up at its far edge, the liquid sheet ejected in a late splash breaks up close to the droplet.

Passive Vaporizing Heat Sink

NASA Technical Reports Server (NTRS)

Knowles, TImothy R.; Ashford, Victor A.; Carpenter, Michael G.; Bier, Thomas M.

2011-01-01

A passive vaporizing heat sink has been developed as a relatively lightweight, compact alternative to related prior heat sinks based, variously, on evaporation of sprayed liquids or on sublimation of solids. This heat sink is designed for short-term dissipation of a large amount of heat and was originally intended for use in regulating the temperature of spacecraft equipment during launch or re-entry. It could also be useful in a terrestrial setting in which there is a requirement for a lightweight, compact means of short-term cooling. This heat sink includes a hermetic package closed with a pressure-relief valve and containing an expendable and rechargeable coolant liquid (e.g., water) and a conductive carbon-fiber wick. The vapor of the liquid escapes when the temperature exceeds the boiling point corresponding to the vapor pressure determined by the setting of the pressure-relief valve. The great advantage of this heat sink over a melting-paraffin or similar phase-change heat sink of equal capacity is that by virtue of the =10x greater latent heat of vaporization, a coolant-liquid volume equal to =1/10 of the paraffin volume can suffice.

Influence of a depletion interaction on dynamical heterogeneity in a dense quasi-two-dimensional colloid liquid.

PubMed

Ho, Hau My; Cui, Bianxiao; Repel, Stephen; Lin, Binhua; Rice, Stuart A

2004-11-01

We report the results of digital video microscopy studies of the large particle displacements in a quasi-two-dimensional binary mixture of large (L) and small (S) colloid particles with diameter ratio sigma(L)/sigma(S)=4.65, as a function of the large and small colloid particle densities. As in the case of the one-component quasi-two-dimensional colloid system, the binary mixtures exhibit structural and dynamical heterogeneity. The distribution of large particle displacements over the time scale examined provides evidence for (at least) two different mechanisms of motion, one associated with particles in locally ordered regions and the other associated with particles in locally disordered regions. When rhoL*=Npisigma(L) (2)/4A< or =0.35, the addition of small colloid particles leads to a monotonic decrease in the large particle diffusion coefficient with increasing small particle volume fraction. When rhoL* > or =0.35 the addition of small colloid particles to a dense system of large colloid particles at first leads to an increase in the large particle diffusion coefficient, which is then followed by the expected decrease of the large particle diffusion coefficient with increasing small colloid particle volume fraction. The mode coupling theory of the ideal glass transition in three-dimensional systems makes a qualitative prediction that agrees with the initial increase in the large particle diffusion coefficient with increasing small particle density. Nevertheless, because the structural and dynamical heterogeneities of the quasi-two-dimensional colloid liquid occur within the field of equilibrium states, and the fluctuations generate locally ordered domains rather than just disordered regions of higher and lower density, it is suggested that mode coupling theory does not account for all classes of relevant fluctuations in a quasi-two-dimensional liquid. (c) 2004 American Institute of Physics.

Versatile Miniature Tunable Liquid Lenses Using Transparent Graphene Electrodes.

PubMed

Shahini, Ali; Xia, Jinjun; Zhou, Zhixian; Zhao, Yang; Cheng, Mark Ming-Cheng

2016-02-16

This paper presents, for the first time, versatile and low-cost miniature liquid lenses with graphene as electrodes. Tunable focal length is achieved by changing the droplet curvature using electrowetting on dielectric (EWOD). Ionic liquid and KCl solution are utilized as lens liquid on the top of a flexible Teflon-coated PDMS/parylene membrane. Transparent and flexible, graphene allows transmission of visible light as well as large deformation of the polymer membrane to achieve requirements for different lens designs and to increase the field of view without damaging of electrodes. The tunable range for the focal length is between 3 and 7 mm for a droplet with a volume of 3 μL. The visualization of bone marrow dendritic cells is demonstrated by the liquid lens system with a high resolution (456 lp/mm).

77 FR 47905 - Self-Regulatory Organizations; NYSE Arca, Inc.; Notice of Filing and Immediate Effectiveness of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-10

...-or-Cancel orders, and (3) maintain a ratio of executed liquidity adding volume-to-total volume of... of CADV, ratio of cancelled orders to total orders and ratio of executed liquidity adding volume-to... ratio of executed liquidity adding volume to total volume of greater than 80%, which is the same ratio...

Thermodynamic properties derived from the free volume model of liquids

NASA Technical Reports Server (NTRS)

Miller, R. I.

1974-01-01

An equation of state and expressions for the isothermal compressibility, thermal expansion coefficient, heat capacity, and entropy of liquids have been derived from the free volume model partition function suggested by Turnbull. The simple definition of the free volume is used, and it is assumed that the specific volume is directly related to the cube of the intermolecular separation by a proportionality factor which is found to be a function of temperature and pressure as well as specific volume. When values of the proportionality factor are calculated from experimental data for real liquids, it is found to be approximately constant over ranges of temperature and pressure which correspond to the dense liquid phase. This result provides a single-parameter method for calculating dense liquid thermodynamic properties and is consistent with the fact that the free volume model is designed to describe liquids near the solidification point.

Liquid volume monitoring based on ultrasonic sensor and Arduino microcontroller

NASA Astrophysics Data System (ADS)

Husni, M.; Siahaan, D. O.; Ciptaningtyas, H. T.; Studiawan, H.; Aliarham, Y. P.

2016-04-01

Incident of oil leakage and theft in oil tank often happens. To prevent it, the liquid volume insides the tank needs to be monitored continuously. Aim of the study is to calculate the liquid volume inside oil tank on any road condition and send the volume data and location data to the user. This research use some ultrasonic sensors (to monitor the fluid height), Bluetooth modules (to sent data from the sensors to the Arduino microcontroller), Arduino Microcontroller (to calculate the liquid volume), and also GPS/GPRS/GSM Shield module (to get location of vehicle and sent the data to the Server). The experimental results show that the accuracy rate of monitoring liquid volume inside tanker while the vehicle is in the flat road is 99.33% and the one while the vehicle is in the road with elevation angle is 84%. Thus, this system can be used to monitor the tanker position and the liquid volume in any road position continuously via web application to prevent illegal theft.

A re-evaluation of thermal expansion measurements of metallic liquids and glasses from x-ray scattering experiments

NASA Astrophysics Data System (ADS)

Gangopadhyay, A. K.; Kelton, K. F.

2018-05-01

Previous studies reported a number of anomalies when estimates of linear thermal expansion coefficients of metallic liquids and glasses from x-ray scattering experiments were compared with direct measurements of volume/length changes with temperature. In most cases, the first peak of the pair correlation function showed a contraction, while the structure factor showed an expansion, but both at rates much different from those expected from the direct volume measurements. In addition, the relationship between atomic volume and the characteristic lengths obtained from the structure factor from scattering experiments was found to have a fractional exponent instead of one equal to three, as expected from the Ehrenfest relation. This has led to the speculation that the atomic packing in liquids and glasses follow a fractal behavior. These issues are revisited in this study using more in-depth analysis of recent higher resolution data and some new ideas suggested in the literature. The main conclusion is that for metallic alloys, at least to a large extent, most of these anomalies arise from complicated interplays of the temperature dependences of the various partial structure factors, which contribute to the total intensities of the scattering peaks.

Determinants of immediate price impacts at the trade level in an emerging order-driven market

NASA Astrophysics Data System (ADS)

Zhou, Wei-Xing

2012-02-01

Common wisdom argues that, in general, large trades cause large price changes, whereas small trades cause small price changes. However, for extremely large price changes, the trade size and news play a minor role, while liquidity (especially price gaps on the limit order book) is a more influential factor. Hence, there might be other factors influencing the immediate price impacts of trades. In this paper, through mechanical analysis of price variations before and after a trade of arbitrary size, we identify that the trade size, the bid-ask spread, the price gaps and the outstanding volumes at the bid and ask sides of the limit order book have an impact on the changes in prices. We propose two regression models to investigate the influence of these microscopic factors on the price impact of buyer-initiated partially filled trades, seller-initiated partially filled trades, buyer-initiated filled trades and seller-initiated filled trades. We find that they have quantitatively similar explanatory powers and these factors can account for up to 44% of the price impacts. Large trade sizes, wide bid-ask spreads, high liquidity at the same side and low liquidity at the opposite side will cause a large price impact. We also find that the liquidity at the opposite side has a more influential impact than the liquidity at the same side. Our results shed new light on the determinants of immediate price impacts.

Viscous hydrodynamic instability theory of the peak and minimum pool boiling heat fluxes

NASA Technical Reports Server (NTRS)

Dhir, V. K.

1972-01-01

Liquid viscosity was included in the Bellman-Pennington theory of the Taylor wave in a liquid vapor interface. Predictions of the most susceptible wavelength, and of the wave frequency, were made as a function of a liquid viscosity parameter and the Bond number. The stability of a gas jet in a viscous liquid was studied and the result is used to predict the peak heat flux on large horizontal heaters. Experimental measurements of the dominant Taylor wave and its growth rate were made during the film boiling of cyclohexanol on cylindrical heaters. The results bear out the predictions quite well. The thickness of the vapor blanket surrounding a cylindrical heater was measured and a correlation suggested. The effect of large fluxes of vapor volume on the dominant wavelength was also noted. Theoretical results of the peak heat flux are compared with the experimental data, and the effect of finite geometry of flat plate heaters on the peak heat flux is also discussed.

Mucous solids and liquid secretion by airways: studies with normal pig, cystic fibrosis human, and non-cystic fibrosis human bronchi

PubMed Central

Martens, Chelsea J.; Inglis, Sarah K.; Valentine, Vincent G.; Garrison, Jennifer; Conner, Gregory E.

2011-01-01

To better understand how airways produce thick airway mucus, nonvolatile solids were measured in liquid secreted by bronchi from normal pig, cystic fibrosis (CF) human, and non-CF human lungs. Bronchi were exposed to various secretagogues and anion secretion inhibitors to induce a range of liquid volume secretion rates. In all three groups, the relationship of solids concentration (percent nonvolatile solids) to liquid volume secretion rate was curvilinear, with higher solids concentration associated with lower rates of liquid volume secretion. In contrast, the secretion rates of solids mass and water mass as functions of liquid volume secretion rates exhibited positive linear correlations. The y-intercepts of the solids mass-liquid volume secretion relationships for all three groups were positive, thus accounting for the higher solids concentrations in airway liquid at low rates of secretion. Predictive models derived from the solids mass and water mass linear equations fit the experimental percent solids data for the three groups. The ratio of solids mass secretion to liquid volume secretion was 5.2 and 2.4 times higher for CF bronchi than for pig and non-CF bronchi, respectively. These results indicate that normal pig, non-CF human, and CF human bronchi produce a high-percent-solids mucus (>8%) at low rates of liquid volume secretion (≤1.0 μl·cm−2·h−1). However, CF bronchi produce mucus with twice the percent solids (∼8%) of pig or non-CF human bronchi at liquid volume secretion rates ≥4.0 μl·cm−2·h−1. PMID:21622844

30 CFR 250.1163 - How must I measure gas flaring or venting volumes and liquid hydrocarbon burning volumes, and...

Code of Federal Regulations, 2011 CFR

2011-07-01

..., including all gas flared, gas vented, and liquid hydrocarbons burned, to Minerals Revenue Management on Form... and maintain records detailing gas flaring, gas venting, and liquid hydrocarbon burning for each... include, at a minimum: (i) Daily volumes of gas flared, gas vented, and liquid hydrocarbons burned; (ii...

The Monte Carlo simulation of the Borexino detector

NASA Astrophysics Data System (ADS)

Agostini, M.; Altenmüller, K.; Appel, S.; Atroshchenko, V.; Bagdasarian, Z.; Basilico, D.; Bellini, G.; Benziger, J.; Bick, D.; Bonfini, G.; Borodikhina, L.; Bravo, D.; Caccianiga, B.; Calaprice, F.; Caminata, A.; Canepa, M.; Caprioli, S.; Carlini, M.; Cavalcante, P.; Chepurnov, A.; Choi, K.; D'Angelo, D.; Davini, S.; Derbin, A.; Ding, X. F.; Di Noto, L.; Drachnev, I.; Fomenko, K.; Formozov, A.; Franco, D.; Froborg, F.; Gabriele, F.; Galbiati, C.; Ghiano, C.; Giammarchi, M.; Goeger-Neff, M.; Goretti, A.; Gromov, M.; Hagner, C.; Houdy, T.; Hungerford, E.; Ianni, Aldo; Ianni, Andrea; Jany, A.; Jeschke, D.; Kobychev, V.; Korablev, D.; Korga, G.; Kryn, D.; Laubenstein, M.; Litvinovich, E.; Lombardi, F.; Lombardi, P.; Ludhova, L.; Lukyanchenko, G.; Machulin, I.; Magnozzi, M.; Manuzio, G.; Marcocci, S.; Martyn, J.; Meroni, E.; Meyer, M.; Miramonti, L.; Misiaszek, M.; Muratova, V.; Neumair, B.; Oberauer, L.; Opitz, B.; Ortica, F.; Pallavicini, M.; Papp, L.; Pocar, A.; Ranucci, G.; Razeto, A.; Re, A.; Romani, A.; Roncin, R.; Rossi, N.; Schönert, S.; Semenov, D.; Shakina, P.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Stokes, L. F. F.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Thurn, J.; Toropova, M.; Unzhakov, E.; Vishneva, A.; Vogelaar, R. B.; von Feilitzsch, F.; Wang, H.; Weinz, S.; Wojcik, M.; Wurm, M.; Yokley, Z.; Zaimidoroga, O.; Zavatarelli, S.; Zuber, K.; Zuzel, G.

2018-01-01

We describe the Monte Carlo (MC) simulation of the Borexino detector and the agreement of its output with data. The Borexino MC "ab initio" simulates the energy loss of particles in all detector components and generates the resulting scintillation photons and their propagation within the liquid scintillator volume. The simulation accounts for absorption, reemission, and scattering of the optical photons and tracks them until they either are absorbed or reach the photocathode of one of the photomultiplier tubes. Photon detection is followed by a comprehensive simulation of the readout electronics response. The MC is tuned using data collected with radioactive calibration sources deployed inside and around the scintillator volume. The simulation reproduces the energy response of the detector, its uniformity within the fiducial scintillator volume relevant to neutrino physics, and the time distribution of detected photons to better than 1% between 100 keV and several MeV. The techniques developed to simulate the Borexino detector and their level of refinement are of possible interest to the neutrino community, especially for current and future large-volume liquid scintillator experiments such as Kamland-Zen, SNO+, and Juno.

Experimental Investigation of Jet-Induced Mixing of a Large Liquid Hydrogen Storage Tank

NASA Technical Reports Server (NTRS)

Lin, C. S.; Hasan, M. M.; Vandresar, N. T.

1994-01-01

Experiments have been conducted to investigate the effect of fluid mixing on the depressurization of a large liquid hydrogen storage tank. The test tank is approximately ellipsoidal, having a volume of 4.89 m(exp 3) and an average wall heat flux of 4.2 W/m(exp 2) due to external heat input. A mixer unit was installed near the bottom of the tank to generate an upward directed axial jet flow normal to the liquid-vapor interface. Mixing tests were initiated after achieving thermally stratified conditions in the tank either by the introduction of hydrogen gas into the tank or by self-pressurization due to ambient heat leak through the tank wall. The subcooled liquid jet directed towards the liquid-vapor interface by the mixer induced vapor condensation and caused a reduction in tank pressure. Tests were conducted at two jet submergence depths for jet Reynolds numbers from 80,000 to 495,000 and Richardson numbers from 0.014 to 0.52. Results show that the rate of tank pressure change is controlled by the competing effects of subcooled jet flow and the free convection boundary layer flow due to external tank wall heating. It is shown that existing correlations for mixing time and vapor condensation rate based on small scale tanks may not be applicable to large scale liquid hydrogen systems.

Explosive change in crater properties during high power nanosecond laser ablation of silicon

NASA Astrophysics Data System (ADS)

Yoo, J. H.; Jeong, S. H.; Greif, R.; Russo, R. E.

2000-08-01

Mass removed from single crystal silicon samples by high irradiance (1×109 to 1×1011W/cm2) single pulse laser ablation was studied by measuring the resulting crater morphology with a white light interferometric microscope. The craters show a strong nonlinear change in both the volume and depth when the laser irradiance is less than or greater than ≈2.2×1010W/cm2. Time-resolved shadowgraph images of the ablated silicon plume were obtained over this irradiance range. The images show that the increase in crater volume and depth at the threshold of 2.2×1010W/cm2 is accompanied by large size droplets leaving the silicon surface, with a time delay ˜300 ns. A numerical model was used to estimate the thickness of the layer heated to approximately the critical temperature. The model includes transformation of liquid metal into liquid dielectric near the critical state (i.e., induced transparency). In this case, the estimated thickness of the superheated layer at a delay time of 200-300 ns shows a close agreement with measured crater depths. Induced transparency is demonstrated to play an important role in the formation of a deep superheated liquid layer, with subsequent explosive boiling responsible for large-particulate ejection.

Determination of solute descriptors by chromatographic methods.

PubMed

Poole, Colin F; Atapattu, Sanka N; Poole, Salwa K; Bell, Andrea K

2009-10-12

The solvation parameter model is now well established as a useful tool for obtaining quantitative structure-property relationships for chemical, biomedical and environmental processes. The model correlates a free-energy related property of a system to six free-energy derived descriptors describing molecular properties. These molecular descriptors are defined as L (gas-liquid partition coefficient on hexadecane at 298K), V (McGowan's characteristic volume), E (excess molar refraction), S (dipolarity/polarizability), A (hydrogen-bond acidity), and B (hydrogen-bond basicity). McGowan's characteristic volume is trivially calculated from structure and the excess molar refraction can be calculated for liquids from their refractive index and easily estimated for solids. The remaining four descriptors are derived by experiment using (largely) two-phase partitioning, chromatography, and solubility measurements. In this article, the use of gas chromatography, reversed-phase liquid chromatography, micellar electrokinetic chromatography, and two-phase partitioning for determining solute descriptors is described. A large database of experimental retention factors and partition coefficients is constructed after first applying selection tools to remove unreliable experimental values and an optimized collection of varied compounds with descriptor values suitable for calibrating chromatographic systems is presented. These optimized descriptors are demonstrated to be robust and more suitable than other groups of descriptors characterizing the separation properties of chromatographic systems.

Oligomerization of Biomass-Derived Light Olefins to Liquid Fuel: Effect of Alkali Treatment of HZSM-5 Catalyst

DOE PAGES

Wang, Xiaoxing; Hu, Xiaoyan; Song, Chunshan; ...

2017-09-27

As a part of a new approach to convert biomass to liquid fuels, we investigated the effects of alkali treatment on the property and performance of HZSM-5 for oligomerization of biomass-derived ethylene under atmospheric pressure. The characterization results showed that alkali treatment led to the increase in the total and mesopore volumes, but decrease in the surface area and micropore volume. Furthermore, when NaOH concentration was low (< 0.5 M), the ZSM-5 structure was largely preserved with the increase in the mesopores and acidity, while higher NaOH concentration can severely destroy the zeolite structure, resulting in a significant reduction inmore » the micropores and acidity. The ethylene oligomerization results showed that not only the ethylene conversion and the liquid yield increased, but also the catalyst stability was improved after proper NaOH treatment. Finally, we discussed the relationship between the structure and performance« less

Oligomerization of Biomass-Derived Light Olefins to Liquid Fuel: Effect of Alkali Treatment of HZSM-5 Catalyst

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

Wang, Xiaoxing; Hu, Xiaoyan; Song, Chunshan

As a part of a new approach to convert biomass to liquid fuels, we investigated the effects of alkali treatment on the property and performance of HZSM-5 for oligomerization of biomass-derived ethylene under atmospheric pressure. The characterization results showed that alkali treatment led to the increase in the total and mesopore volumes, but decrease in the surface area and micropore volume. Furthermore, when NaOH concentration was low (< 0.5 M), the ZSM-5 structure was largely preserved with the increase in the mesopores and acidity, while higher NaOH concentration can severely destroy the zeolite structure, resulting in a significant reduction inmore » the micropores and acidity. The ethylene oligomerization results showed that not only the ethylene conversion and the liquid yield increased, but also the catalyst stability was improved after proper NaOH treatment. Finally, we discussed the relationship between the structure and performance« less

Sludge reduction and water quality improvement in anaerobic lagoons through influent pre-treatment

USDA-ARS?s Scientific Manuscript database

Confined swine production generates large volumes of wastewater typically stored and treated in anaerobic lagoons. These lagoons may require cleanup and closure measures in the future. In practice, liquid and sludge need to be removed by pumping, usually at great expense of energy, and land applied ...

Controlling the pressure within an annular volume of a wellbore

DOEpatents

Hermes, Robert E.; Gonzalez, Manuel E.; Llewellyn, Brian C.; Bloys, James B.

2008-10-28

A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.

Controlling the pressure within an annular volume of a wellbore

DOEpatents

Hermes, Robert E [Los Alamos, NM; Gonzalez, Manuel E [Kingwood, TX; Llewellyn, Brian C [Kingwood, TX; Bloys, James B [Katy, TX; Coates, Don M [Santa Fe, NM

2011-05-31

A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.

Controlling the pressure within an annular volume of a wellbore

DOEpatents

Hermes, Robert E [Los Alamos, NM; Gonzalez, Manuel E [Kingwood, TX; Llewellyn, Brian C [Kingwood, TX; Bloys, James B [Katy, TX

2011-01-18

A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.

Controlling the pressure within an annular volume of a wellbore

DOEpatents

Hermes, Robert E.; Gonzalez, Manuel E.; Llewellyn, Brian C.; Bloys, James B.

2010-06-29

A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.

Controlling the pressure within an annular volume of a wellbore

DOEpatents

Hermes, Robert E [Los Alamos, NM; Gonzalez, Manuel E [Kingwood, NM; Llewellyn, Brian C [Kingwood, TX; Bloys, James B [Katy, TX; Coates, Don M [Santa Fe, NM

2011-06-21

A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.

GraXe, graphene and xenon for neutrinoless double beta decay searches

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

Gómez-Cadenas, J.J.; Martín-Albo, J.; Monrabal, F.

2012-02-01

We propose a new detector concept, GraXe (to be pronounced as grace), to search for neutrinoless double beta decay in {sup 136}XE. GraXe combines a popular detection medium in rare-event searches, liquid xenon, with a new, background-free material, graphene. In our baseline design of GraXe, a sphere made of graphene-coated titanium mesh and filled with liquid xenon (LXe) enriched in the {sup 136}XE isotope is immersed in a large volume of natural LXe instrumented with photodetectors. Liquid xenon is an excellent scintillator, reasonably transparent to its own light. Graphene is transparent over a large frequency range, and impermeable to themore » xenon. Event position could be deduced from the light pattern detected in the photosensors. External backgrounds would be shielded by the buffer of natural LXe, leaving the ultra-radiopure internal volume virtually free of background. Industrial graphene can be manufactured at a competitive cost to produce the sphere. Enriching xenon in the isotope {sup 136}XE is easy and relatively cheap, and there is already near one ton of enriched xenon available in the world (currently being used by the EXO, KamLAND-Zen and NEXT experiments). All the cryogenic know-how is readily available from the numerous experiments using liquid xenon. An experiment using the GraXe concept appears realistic and affordable in a short time scale, and its physics potential is enormous.« less

Fluvial Volumes, Timescales, and Intermittency in Milna Crater, Mars

NASA Technical Reports Server (NTRS)

Buhler, P.; Fassett, C. I.; Head, J. W.; Lamb, M. P.

2017-01-01

Ancient lake deposits and valley networks on Mars provide strong evidence that its surface was once modified by liquid water, but the extent of that modification is still debated. Ancient lacustrine deposits in Milna Crater provide insight into the timescale and fluid volume required to construct fluvially derived sedimentary deposits near the Noachian-Hesperian boundary. Placing the lacustrine deposits their regional context in Paraná Valles provides a quantitative measurement of the intermittency of large, water-mediated sediment transport events in that region.

Nebulization Reflux Concentrator

NASA Technical Reports Server (NTRS)

Cofer, Wesley R., III; Collins, V. G.

1986-01-01

Nebulization reflux concentrator extracts and concentrates trace quantities of water-soluble gases for subsequent chemical analysis. Hydrophobic membrane and nebulizing nozzles form scrubber for removing trace quantities of soluble gases or other contaminants from atmosphere. Although hydrophobic membrane virtually blocks all transport of droplets, it offers little resistance to gas flow; hence, device permits relatively large volumes of gas scrubbed efficiently with very small volumes of liquid. This means analyzable quantities of contaminants concentrate in extracting solutions in much shorter times than with conventional techniques.

1H-NMR and HPLC studies of the changes involved in volume regulation in the muscle fibres of the crab, Hemigrapsus edwardsi.

PubMed

Bedford, J J; Smith, R A; Thomas, M; Leader, J P

1991-01-01

1. The process of cell volume readjustment, during adaptation to salinity changes, in muscle fibres of the euryhaline New Zealand shore crab, Hemigrapsus edwardsi, involve large changes in the amounts of free amino acid. 2. These are taurine, proline, alanine, arginine, glutamic acid, glycine and serine. 3. These changes may be quantified by High Performance Liquid Chromatography, and qualitatively demonstrated by proton nuclear magnetic resonance spectroscopy.

30 CFR 250.1163 - How must I measure gas flaring or venting volumes and liquid hydrocarbon burning volumes, and...

Code of Federal Regulations, 2012 CFR

2012-07-01

..., gas vented, and liquid hydrocarbons burned, to Office of Natural Resources Revenue on Form ONRR-4054... records detailing gas flaring, gas venting, and liquid hydrocarbon burning for each facility for 6 years... minimum: (i) Daily volumes of gas flared, gas vented, and liquid hydrocarbons burned; (ii) Number of hours...

30 CFR 250.1163 - How must I measure gas flaring or venting volumes and liquid hydrocarbon burning volumes, and...

Code of Federal Regulations, 2010 CFR

2010-07-01

..., and Burning Hydrocarbons § 250.1163 How must I measure gas flaring or venting volumes and liquid... vented, and liquid hydrocarbons burned, to Minerals Revenue Management on Form MMS-4054 (Oil and Gas... gas flaring, gas venting, and liquid hydrocarbon burning for each facility for 6 years. (1) You must...

30 CFR 250.1163 - How must I measure gas flaring or venting volumes and liquid hydrocarbon burning volumes, and...

Code of Federal Regulations, 2013 CFR

2013-07-01

..., gas vented, and liquid hydrocarbons burned, to Office of Natural Resources Revenue on Form ONRR-4054... records detailing gas flaring, gas venting, and liquid hydrocarbon burning for each facility for 6 years... minimum: (i) Daily volumes of gas flared, gas vented, and liquid hydrocarbons burned; (ii) Number of hours...

30 CFR 250.1163 - How must I measure gas flaring or venting volumes and liquid hydrocarbon burning volumes, and...

Code of Federal Regulations, 2014 CFR

2014-07-01

..., gas vented, and liquid hydrocarbons burned, to Office of Natural Resources Revenue on Form ONRR-4054... records detailing gas flaring, gas venting, and liquid hydrocarbon burning for each facility for 6 years... minimum: (i) Daily volumes of gas flared, gas vented, and liquid hydrocarbons burned; (ii) Number of hours...

Leidenfrost phenomenon on conical surfaces

NASA Astrophysics Data System (ADS)

Hidalgo-Caballero, S.; Escobar-Ortega, Y.; Pacheco-Vázquez, F.

2016-09-01

The Leidenfrost state is typically studied by placing droplets on flat or slightly curved surfaces. Here this phenomenon is investigated by depositing water in hot conical bowls. We found that this phase exists even for large amounts of liquid in very narrow cones without considerable effect of the confinement on the Leidenfrost transition temperature TL. At a fixed temperature, T >TL , the total evaporation time τ has a nonmonotonic dependence on the angle of confinement θ : for large volumes (˜20 ml) on flat surfaces (θ ˜0∘ ), vapor chimneys appear and accelerate the evaporation rate, their frequency diminishes as θ augments and becomes zero at a certain angle θc, at which τ reaches its maximum value; then, τ decreases again at larger angles because the vapor layer holding up the water becomes thinner due to the increase of hydrostatic pressure and because the geometry facilitates the vapor expulsion along the conical wall. For small volumes (˜1 ml), surface tension mainly determines the drop curvature and the lifetime is practically independent of θ . Different chimney regimes and oscillation patterns were observed and summarized in a phase diagram. Finally, we developed a simple model to decipher the shape adopted by the liquid volume and its evolution as a function of time, and the predictions are in good agreement with the experimental results.

Single and two-phase flows of shear-thinning media in safety valves.

PubMed

Moncalvo, D; Friedel, L

2009-09-15

This study is the first one in the scientific literature to investigate the liquid and two-phase flows of shear-thinning media, here aqueous solutions of polyvinylpyrrolidone, in a fully opened safety valve. In liquid flows the volume flux at the valve seat does not show any appreciable reduction when increasing the percental weight of polymer in the solution. This result may suggest that the viscous losses in the valve do not increase sensibly from the most aqueous to the most viscous solution. The authors explain it considering that in the region between the seat and the disk, where large pressure and velocity gradients occur, large shear rates are expected. On behalf of the rheological measurements, which show that both the pseudoplasticity and the zero-shear viscosity of the solutions increase with the polymer weight, the difference between the viscosities of the most viscous and those of the most aqueous solution is between the seat and the disk far less than that existing at zero-shear condition. Therefore, the effective viscous pressure drop of the safety valve, which occurs mostly in that region, must increase only modestly with the polymer percental weight in the solution. In two-phase flows the total mass flow rate at constant quality and constant relieving pressure increases remarkably with the polymer weight. The analogy with similar results in cocurrent pipe flows suggests that air entrainment causes large velocity gradients in the liquids and strains them to very large shear rates. It suggests also that a redistribution of the gas agglomerates within the liquid must be expected when increasing the polymer weight in the solutions. In fact, the gas agglomerates react to the larger viscous drag of the liquid by compressing their volume in order to exert a higher internal pressure. The reduction of the void fraction of the mixture at constant quality and constant relieving pressure imposes an increment in the total mass flow rate, since otherwise it would lead to a reduction in the momentum of the mixture and therefore to a drop in the relieving pressure.

To what extent does terrestrial life "follow the water"?

PubMed

Jones, Eriita G; Lineweaver, Charles H

2010-04-01

Terrestrial life is known to require liquid water, but not all terrestrial water is inhabited. Thus, liquid water is a necessary, but not sufficient, condition for life. To quantify the terrestrial limits on the habitability of water and help identify the factors that make some terrestrial water uninhabited, we present empirical pressure-temperature (P-T) phase diagrams of water, Earth, and terrestrial life. Eighty-eight percent of the volume of Earth where liquid water exists is not known to host life. This potentially uninhabited terrestrial liquid water includes (i) hot and deep regions of Earth where some combination of high temperature (T > 122 degrees C) and restrictions on pore space, nutrients, and energy is the limiting factor and (ii) cold and near-surface regions of Earth, such as brine inclusions and thin films in ice and permafrost (depths less than approximately 1 km), where low temperatures (T < -40 degrees C), low water activity (a(w) < 0.6), or both are the limiting factors. If the known limits of terrestrial life do not change significantly, these limits represent important constraints on our biosphere and, potentially, on others, since approximately 4 billion years of evolution have not allowed life to adapt to a large fraction of the volume of Earth where liquid water exists.

Modeling the liquid filling in capillary well microplates for analyte preconcentration.

PubMed

Yu, Yang; Wang, Xuewei; Ng, Tuck Wah

2012-06-15

An attractive advantage of the capillary well microplate approach is the ability to conduct evaporative analyte preconcentration. We advance the use of hydrophobic materials for the wells which apart from reducing material loss through wetting also affords self entry into the well when the droplet size reduces below a critical value. Using Surface Evolver simulation without gravity, we find the critical diameters D(c) fitting very well with theoretical results. When simulating the critical diameters D(c)(G) with gravity included, the gravitational effect could only be ignored when the liquid volumes were small (difference of 5.7% with 5 μL of liquid), but not when the liquid volumes were large (differences of more than 22% with 50 μL of liquid). From this, we developed a modifying equation from a series of simulation results made to describe the gravitational effect. This modifying equation fitted the simulation results well in our simulation range (100°≤θ≤135° and 1 μL≤V≤200 μL). In simulating the condition of multiple wells underneath each droplet, we found that having more holes did not alter the critical diameters significantly. Consequently, the modifying relation should also generally express the critical diameter for multiple wells under a droplet. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

Low Energy Neutrino Astronomy in the future large-volume liquid-scintillator detector LENA

NASA Astrophysics Data System (ADS)

Wurm, Michael; Feilitzsch, F. V.; Göger-Neff, M.; Lewke, T.; Marrodan Undagoitia, T.; Oberauer, L.; Potzel, W.; Todor, S.; Winter, J.

2008-11-01

The recent successes in neutrino physics prove that liquid-scintillator detectors allow to combine high energy resolution, efficient means of background reduction, and a large detection volume. In the planned LENA (Low Energy Neutrino Astronomy) experiment, a target mass of 50 kt will enable the investigation of a variety of terrestrial and astrophysical neutrino sources. The high-statistics spectroscopy of geoneutrinos, solar neutrinos and supernova neutrinos will provide new insights in the heat production processes of Earth and Sun, and the workings of a gravitational collapse. The same measurements will as well investigate neutrino properties as oscillation parameters and mass hierarchy. A first spectroscopic measurement of the low flux of diffuse supernova neutrino background is within the sensitivity of the LENA detector. Finally, a life-time limit of several 1034 years can be set to the proton decay into proton and anti-neutrino, testing the predictions of SUSY theory. The present contribution includes a review of the scientific studies that were performed in the last years as well as a report on currently on-going R&D activities.

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.

Levitation of a drop over a film flow

NASA Astrophysics Data System (ADS)

Sreenivas, K. R.; de, P. K.; Arakeri, Jaywant H.

1999-02-01

A vertical jet of water impinging on a horizontal surface produces a radial film flow followed by a circular hydraulic jump. We report a phenomenon where fairly large (1 ml) drops of liquid levitate just upstream of the jump on a thin air layer between the drop and the film flow. We explain the phenomenon using lubrication theory. Bearing action both in the air film and the water film seems to be necessary to support large drops. Horizontal support is given to the drop by the hydraulic jump. A variety of drop shapes is observed depending on the volume of the drop and liquid properties. We show that interaction of the forces due to gravity, surface tension, viscosity and inertia produces these various shapes.

Supporting implementation of evidence-based behavioral interventions: the role of data liquidity in facilitating translational behavioral medicine.

PubMed

Abernethy, Amy P; Wheeler, Jane L; Courtney, Paul K; Keefe, Francis J

2011-03-01

The advancement of translational behavioral medicine will require that we discover new methods of managing large volumes of data from disparate sources such as disease surveillance systems, public health systems, and health information systems containing patient-centered data informed by behavioral and social sciences. The term "liquidity," when applied to data, refers to its availability and free flow throughout human/computer interactions. In seeking to achieve liquidity, the focus is not on creating a single, comprehensive database or set of coordinated datasets, nor is it solely on developing the electronic health record as the "one-stop shopping" source of health-related data. Rather, attention is on ensuring the availability of secure data through the various methods of collecting and storing data currently existent or under development-so that these components of the health information infrastructure together support a liquid data system. The value of accessible, interoperable, high-volume, reliable, secure, and contextually appropriate data is becoming apparent in many areas of the healthcare system, and health information liquidity is currently viewed as an important component of a patient-centered healthcare system. The translation from research interventions to behavioral and psychosocial indicators challenges the designers of healthcare systems to include this new set of data in the correct context. With the intention of advancing translational behavioral medicine at the local level, "on the ground" in the clinical office and research institution, this commentary discusses data liquidity from the patient's and clinician's perspective, requirements for a liquid healthcare data system, and the ways in which data liquidity can support translational behavioral medicine.

Effect of particle size on the glass transition.

PubMed

Larsen, Ryan J; Zukoski, Charles F

2011-05-01

The glass transition temperature of a broad class of molecules is shown to depend on molecular size. This dependency results from the size dependence of the pair potential. A generalized equation of state is used to estimate how the volume fraction at the glass transition depends on the size of the molecule, for rigid molecule glass-formers. The model shows that at a given pressure and temperature there is a size-induced glass transition: For molecules larger than a critical size, the volume fraction required to support the effective pressure due to particle attractions is above that which characterizes the glassy state. This observation establishes the boundary between nanoparticles, which exist in liquid form only as dispersions in low molecular weight solvents and large molecules which form liquids that have viscosities below those characterized by the glassy state.

Large catchment area recharges Titan's Ontario Lacus

NASA Astrophysics Data System (ADS)

Dhingra, Rajani D.; Barnes, Jason W.; Yanites, Brian J.; Kirk, Randolph L.

2018-01-01

We seek to address the question of what processes are at work to fill Ontario Lacus while other, deeper south polar basins remain empty. Our hydrological analysis indicates that Ontario Lacus has a catchment area spanning 5.5% of Titan's surface and a large catchment area to lake surface area ratio. This large catchment area translates into large volumes of liquid making their way to Ontario Lacus after rainfall. The areal extent of the catchment extends to at least southern mid-latitudes (40°S). Mass conservation calculations indicate that runoff alone might completely fill Ontario Lacus within less than half a Titan year (1 Titan year = 29.5 Earth years) assuming no infiltration. Cassini Visual and Infrared Mapping Spectrometer (VIMS) observations of clouds over the southern mid and high-latitudes are consistent with precipitation feeding Ontario's large catchment area. This far-flung rain may be keeping Ontario Lacus filled, making it a liquid hydrocarbon oasis in the relatively dry south polar region.

VOLUME COMPENSATING MEANS FOR PULSATING PUMPS

DOEpatents

Weaver, D.L.W.; MacCormack, R.S. Jr.

1959-12-01

A double diaphragm, two-liquid pulsating pump for remote control use, having as an improvement an apparatus for maintaining constant the volume of the liquid such as kerosene between the two diaphragms is described. Phase difficulties encountered in the operation of such pumps when the volume of the liquid is altered by changes in temperature are avoided.

Lattice model for water-solute mixtures.

PubMed

Furlan, A P; Almarza, N G; Barbosa, M C

2016-10-14

A lattice model for the study of mixtures of associating liquids is proposed. Solvent and solute are modeled by adapting the associating lattice gas (ALG) model. The nature of interaction of solute/solvent is controlled by tuning the energy interactions between the patches of ALG model. We have studied three set of parameters, resulting in, hydrophilic, inert, and hydrophobic interactions. Extensive Monte Carlo simulations were carried out, and the behavior of pure components and the excess properties of the mixtures have been studied. The pure components, water (solvent) and solute, have quite similar phase diagrams, presenting gas, low density liquid, and high density liquid phases. In the case of solute, the regions of coexistence are substantially reduced when compared with both the water and the standard ALG models. A numerical procedure has been developed in order to attain series of results at constant pressure from simulations of the lattice gas model in the grand canonical ensemble. The excess properties of the mixtures, volume and enthalpy as the function of the solute fraction, have been studied for different interaction parameters of the model. Our model is able to reproduce qualitatively well the excess volume and enthalpy for different aqueous solutions. For the hydrophilic case, we show that the model is able to reproduce the excess volume and enthalpy of mixtures of small alcohols and amines. The inert case reproduces the behavior of large alcohols such as propanol, butanol, and pentanol. For the last case (hydrophobic), the excess properties reproduce the behavior of ionic liquids in aqueous solution.

Gas-Enhanced Ultra-High Shear Mixing: A Concept and Applications

NASA Astrophysics Data System (ADS)

Czerwinski, Frank; Birsan, Gabriel

2017-04-01

The processes of mixing, homogenizing, and deagglomeration are of paramount importance in many industries for modifying properties of liquids or liquid-based dispersions at room temperature and treatment of molten or semi-molten alloys at high temperatures, prior to their solidification. To implement treatments, a variety of technologies based on mechanical, electromagnetic, and ultrasonic principles are used commercially or tested at the laboratory scale. In a large number of techniques, especially those tailored toward metallurgical applications, the vital role is played by cavitation, generation of gas bubbles, and their interaction with the melt. This paper describes a novel concept exploring an integration of gas injection into the shear zone with ultra-high shear mixing. As revealed via experiments with a prototype of the cylindrical rotor-stator apparatus and transparent media, gases injected radially through the high-speed rotor generate highly refined bubbles of high concentration directly in the shear zone of the mixer. It is believed that an interaction of large volume of fine gas bubbles with the liquid, superimposed on ultra-high shear, will enhance mixing capabilities and cause superior refining and homogenizing of the liquids or solid-liquid slurries, thus allowing their effective property modification.

Ni, Cu, Au, and platinum-group element contents of sulphides associated with intraplate magmatism: A synthesis

USGS Publications Warehouse

Barnes, S.-J.; Zientek, M.L.; Severson, M.J.

1997-01-01

The tectonic setting of intraplate magmas, typically a plume intersecting a rift, is ideal for the development of Ni - Cu - platinum-group element-bearing sulphides. The plume transports metal-rich magmas close to the mantle - crust boundary. The interaction of the rift and plume permits rapid transport of the magma into the crust, thus ensuring that no sulphides are lost from the magma en route to the crust. The rift may contain sediments which could provide the sulphur necessary to bring about sulphide saturation in the magmas. The plume provides large volumes of mafic magma; thus any sulphides that form can collect metals from a large volume of magma and consequently the sulphides will be metal rich. The large volume of magma provides sufficient heat to release large quantities of S from the crust, thus providing sufficient S to form a large sulphide deposit. The composition of the sulphides varies on a number of scales: (i) there is a variation between geographic areas, in which sulphides from the Noril'sk - Talnakh area are the richest in metals and those from the Muskox intrusion are poorest in metals; (ii) there is a variation between textural types of sulphides, in which disseminated sulphides are generally richer in metals than the associated massive and matrix sulphides; and (iii) the massive and matrix sulphides show a much wider range of compositions than the disseminated sulphides, and on the basis of their Ni/Cu ratio the massive and matrix sulphides can be divided into Cu rich and Fe rich. The Cu-rich sulphides are also enriched in Pt, Pd, and Au; in contrast, the Fe-rich sulphides are enriched in Fe, Os, Ir, Ru, and Rh. Nickel concentrations are similar in both. Differences in the composition between the sulphides from different areas may be attributed to a combination of differences in composition of the silicate magma from which the sulphides segregated and differences in the ratio of silicate to sulphide liquid (R factors). The higher metal content of the disseminated sulphides relative to the massive and matrix sulphides may be due to the fact that the disseminated sulphides equilibrated with a larger volume of magma than massive and matrix sulphides. The difference in composition between the Cu- and Fe-rich sulphides may be the result of the fractional crystallization of monosulphide solid solution from a sulphide liquid, with the Cu-rich sulphides representing the liquid and the Fe-rich sulphides representing the cumulate.

Large-Flow-Area Flow-Selective Liquid/Gas Separator

NASA Technical Reports Server (NTRS)

Vasquez, Arturo; Bradley, Karla F.

2010-01-01

This liquid/gas separator provides the basis for a first stage of a fuel cell product water/oxygen gas phase separator. It can separate liquid and gas in bulk in multiple gravity environments. The system separates fuel cell product water entrained with circulating oxygen gas from the outlet of a fuel cell stack before allowing the gas to return to the fuel cell stack inlet. Additional makeup oxygen gas is added either before or after the separator to account for the gas consumed in the fuel cell power plant. A large volume is provided upstream of porous material in the separator to allow for the collection of water that does not exit the separator with the outgoing oxygen gas. The water then can be removed as it continues to collect, so that the accumulation of water does not impede the separating action of the device. The system is designed with a series of tubes of the porous material configured into a shell-and-tube heat exchanger configuration. The two-phase fluid stream to be separated enters the shell-side portion of the device. Gas flows to the center passages of the tubes through the porous material and is then routed to a common volume at the end of the tubes by simple pressure difference from a pumping device. Gas flows through the porous material of the tubes with greater ease as a function of the ratio of the dynamic viscosity of the water and gas. By careful selection of the dimensions of the tubes (wall thickness, porosity, diameter, length of the tubes, number of the tubes, and tube-to-tube spacing in the shell volume) a suitable design can be made to match the magnitude of water and gas flow, developed pressures from the oxygen reactant pumping device, and required residual water inventory for the shellside volume.

Viscosity Measurement of Highly Viscous Liquids Using Drop Coalescence in Low Gravity

NASA Technical Reports Server (NTRS)

Antar, Basil N.; Ethridge, Edwin; Maxwell, Daniel

1999-01-01

The method of drop coalescence is being investigated for use as a method for determining the viscosity of highly viscous undercooled liquids. Low gravity environment is necessary in this case to minimize the undesirable effects of body forces and liquid motion in levitated drops. Also, the low gravity environment will allow for investigating large liquid volumes which can lead to much higher accuracy for the viscosity calculations than possible under 1 - g conditions. The drop coalescence method is preferred over the drop oscillation technique since the latter method can only be applied for liquids with vanishingly small viscosities. The technique developed relies on both the highly accurate solution of the Navier-Stokes equations as well as on data from experiments conducted in near zero gravity environment. In the analytical aspect of the method two liquid volumes are brought into contact which will coalesce under the action of surface tension alone. The free surface geometry development as well as its velocity during coalescence which are obtained from numerical computations are compared with an analogous experimental model. The viscosity in the numerical computations is then adjusted to bring into agreement of the experimental results with the calculations. The true liquid viscosity is the one which brings the experiment closest to the calculations. Results are presented for method validation experiments performed recently on board the NASA/KC-135 aircraft. The numerical solution for this validation case was produced using the Boundary Element Method. In these tests the viscosity of a highly viscous liquid, in this case glycerine at room temperature, was determined to high degree of accuracy using the liquid coalescence method. These experiments gave very encouraging results which will be discussed together with plans for implementing the method in a shuttle flight experiment.

Liquid hydrogen thermal energy storage unit for future ESA science missions

NASA Astrophysics Data System (ADS)

Sousa, Patricia Tavares Coutinho Borges de

The X-IFU instrument for X-ray observation on ESA's new ATHENA satellite will employ a complex cryogenic chain for detector cooling down to 50mK. The existence of heat peaks during the recycling stages of a 300mK cooler can compromise the stability of the entire chain; this issue can be solved by using large cryogenic liquid reservoirs or by over-dimensioning the system. However, these solutions are either costly or temporary, as cryogenic liquids will eventually run out. An Energy Storage Unit (ESU) using liquid hydrogen has been developed as a solution for absorbing 400 J of thermal energy in 30 min between 15K and 16K by taking advantage of the liquid-to-vapour latent heat of hydrogen in a closed system. The ESU is composed of a low temperature liquid hydrogen reservoir, two intermediate interfaces for gas pre-cooling and a hydrogen storage vessel at room temperature. This vessel can either be a 56-litre expansion volume (for ground testing) or a canister filled with a metal hydride, LaNi4:8Sn0:2, that chemically absorbs hydrogen in its atomic form. The latter largely reduces the volume of the vessel and enables working at near-constant pressure and temperature. Two devices have been developed for this project: a Development Model breadboard device used for preliminary testing and the Engineering Model, the final model of the ESU that is to be delivered to ESA and that was subjected to severe mechanical testing in order to comply with strict requirements. Results obtained with both models show that 400 J can be absorbed with a temperature increase of 2K when a 56-litre expansion volume is used, while results using metal hydrides show that the same heat load can be absorbed between 15K and 16:5K, where the cold cell temperature is above 16K for less than 10 min. Full regeneration of the ESU can be achieved in under 24 h without exceeding the cooling power available at the different temperature stages. Experimental results are discussed and suggestions for further improvement are proposed. None None None None None None None None None None None None None None None None None None None None None None None None None None

Construction and Start-up of a Large-Volume Thermostat for Dielectric-Constant Gas Thermometry

NASA Astrophysics Data System (ADS)

Merlone, A.; Moro, F.; Zandt, T.; Gaiser, C.; Fellmuth, B.

2010-07-01

A liquid-bath thermostat with a volume of about 800 L was designed to provide a suitable thermal environment for a dielectric-constant gas thermometer (DCGT) in the range from the triple point of mercury to the melting point of gallium. In the article, results obtained with the unique, huge thermostat without the DCGT measuring chamber are reported to demonstrate the capability of controlling the temperature of very large systems at a metrological level. First tests showed that the bath together with its temperature controller provide a temperature variation of less than ±0.5mK peak-to-peak. This temperature instability could be maintained over a period of several days. In the central working volume (diameter—500mm, height—650mm), in which the vacuum chamber containing the measuring system of the DCGT will be placed later, the temperature inhomogeneity has been demonstrated to be also well below 1mK.

Polymeric ionic liquid-based portable tip microextraction device for on-site sample preparation of water samples.

PubMed

Chen, Lei; Pei, Junxian; Huang, Xiaojia; Lu, Min

2018-06-05

On-site sample preparation is highly desired because it avoids the transportation of large-volume samples and ensures the accuracy of the analytical results. In this work, a portable prototype of tip microextraction device (TMD) was designed and developed for on-site sample pretreatment. The assembly procedure of TMD is quite simple. Firstly, polymeric ionic liquid (PIL)-based adsorbent was in-situ prepared in a pipette tip. After that, the tip was connected with a syringe which was driven by a bidirectional motor. The flow rates in adsorption and desorption steps were controlled accurately by the motor. To evaluate the practicability of the developed device, the TMD was used to on-site sample preparation of waters and combined with high-performance liquid chromatography with diode array detection to measure trace estrogens in water samples. Under the most favorable conditions, the limits of detection (LODs, S/N = 3) for the target analytes were in the range of 4.9-22 ng/L, with good coefficients of determination. Confirmatory study well evidences that the extraction performance of TMD is comparable to that of the traditional laboratory solid-phase extraction process, but the proposed TMD is more simple and convenient. At the same time, the TMD avoids complicated sampling and transferring steps of large-volume water samples. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of viscosity, taste, and bolus volume on swallowing apnea duration of normal adults.

PubMed

Butler, Susan G; Postma, Gregory N; Fischer, Eileen

2004-12-01

The effects of viscosity, taste, and nectar-thick liquid bolus volume on swallowing apnea duration (SAD) were examined. Twenty-two adults, comprised of 10 males and 12 females, participated. SAD was assessed via nasal airflow during swallow conditions of viscosity (thin liquid, thick liquid, and puree), taste (water, apple juice, lemon concentrate), and nectar-thick liquid bolus volumes (5, 10, 15, and 20 mL) across three trials. A significant main effect of nectar-thick liquid bolus volume was found (P < 0.05). Viscosity and taste were not significant. SAD increased with increases in bolus volume; however, neither changes in bolus viscosity nor changes in taste affected SAD. These findings indicate that since viscosity was not significant, the normative data previously published (by this PI) with 60 healthy adults stratified by age and gender can be utilized for comparison to disordered swallowing without regard to the bolus viscosity being used. D.

Development of a high-resolution liquid xenon detector for gamma-ray astrophysics

NASA Astrophysics Data System (ADS)

Mukherjee, Reshmi

It has been shown here that liquid xenon is one of the most promising detector media for future gamma-ray detectors, owing to an excellent combination of physical properties. The feasibility of the construction of a high resolution liquid xenon detector as a gamma-ray detector for astrophysics has been demonstrated. Up to 3.5 liters of liquid xenon has been successfully purified and using both small and large volume prototypes, the charge and the energy resolution response of such detectors to gamma-rays, internal conversion electrons and alpha particles have been measured. The best energy resolution measured was 4.5 percent FWHM at 1 MeV. Cosmic ray tracks have been imaged using a 2-dimensional liquid xenon multiwire imaging chamber. The spatial resolution along the direction of the drifting electrons was 180 microns rms. Experiments have been performed to study the scintillation light in liquid xenon, as the prompt scintillation signal in the liquid is an electron-ion pair in liquid krypton was measured for the first time with a pulsed ionization chamber to be 18.4 plus or minus 0.3 eV.

Focusing analytes from 50 μL into 500 pL: On-chip focusing from large sample volumes using isotachophoresis.

PubMed

van Kooten, Xander F; Truman-Rosentsvit, Marianna; Kaigala, Govind V; Bercovici, Moran

2017-09-05

The use of on-chip isotachophoresis assays for diagnostic applications is often limited by the small volumes of standard microfluidic channels. Overcoming this limitation is particularly important for detection of 'discrete' biological targets (such as bacteria) at low concentrations, where the volume of processed liquid in a standard microchannel might not contain any targets. We present a novel microfluidic chip that enables ITP focusing of target analytes from initial sample volumes of 50 μL into a concentrated zone with a volume of 500 pL, corresponding to a 100,000-fold increase in mean concentration, and a 300,000-fold increase in peak concentration. We present design considerations for limiting sample dispersion in such large-volume focusing (LVF) chips and discuss the trade-off between assay time and Joule heating, which ultimately governs the scalability of LVF designs. Finally, we demonstrate a 100-fold improvement of ITP focusing performance in the LVF chip as compared to conventional microchannels, and apply this enhancement to achieve highly sensitive detection of both molecular targets (DNA, down to 10 fM) and whole bacteria (down to 100 cfu/mL).

Field-scale moisture estimates using COSMOS sensors: a validation study with temporary networks and leaf-area-indices

USDA-ARS?s Scientific Manuscript database

The Cosmic-ray Soil Moisture Observing System (COSMOS) is a new and innovative method for estimating surface and near surface soil moisture at large (~700 m) scales. This system accounts for liquid water within its measurement volume. Many of the sites used in the early validation of the system had...

Performance of ceramic superconductors in magnetic bearings

NASA Technical Reports Server (NTRS)

Kirtley, James L., Jr.; Downer, James R.

1993-01-01

Magnetic bearings are large-scale applications of magnet technology, quite similar in certain ways to synchronous machinery. They require substantial flux density over relatively large volumes of space. Large flux density is required to have satisfactory force density. Satisfactory dynamic response requires that magnetic circuit permeances not be too large, implying large air gaps. Superconductors, which offer large magnetomotive forces and high flux density in low permeance circuits, appear to be desirable in these situations. Flux densities substantially in excess of those possible with iron can be produced, and no ferromagnetic material is required. Thus the inductance of active coils can be made low, indicating good dynamic response of the bearing system. The principal difficulty in using superconductors is, of course, the deep cryogenic temperatures at which they must operate. Because of the difficulties in working with liquid helium, the possibility of superconductors which can be operated in liquid nitrogen is thought to extend the number and range of applications of superconductivity. Critical temperatures of about 98 degrees Kelvin were demonstrated in a class of materials which are, in fact, ceramics. Quite a bit of public attention was attracted to these new materials. There is a difficulty with the ceramic superconducting materials which were developed to date. Current densities sufficient for use in large-scale applications have not been demonstrated. In order to be useful, superconductors must be capable of carrying substantial currents in the presence of large magnetic fields. The possible use of ceramic superconductors in magnetic bearings is investigated and discussed and requirements that must be achieved by superconductors operating at liquid nitrogen temperatures to make their use comparable with niobium-titanium superconductors operating at liquid helium temperatures are identified.

Stability Limits and Dynamics of Nonaxisymmetric Liquid Bridges

NASA Technical Reports Server (NTRS)

Alexander, J. Iwan D.; Slobozhanin, Lev A.; Resnick, Andrew H.; Ramus, Jean-Francois; Delafontaine, Sylvie

1999-01-01

Liquid bridges have been the focus of numerous theoretical and experimental investigations since the early work by Plateau more than a century ago. More recently, motivated by interest in their physical behavior and their occurrence in a variety of technological situations, there has been a resurgence of interest in the static and dynamic behavior of liquid bridges. Furthermore, opportunities to carry out experiments in the near weightless environment of a low-Earth-orbit spacecraft have also led to a number of low-gravity experiments involving large liquid bridges. In this paper, we present selected results from our work concerning the stability of nonaxisymmetric liquid bridges, the bifurcation of weightless bridges in the neighborhood of the maximum volume stability limit, isorotating axisymmetric bridges contained between equidimensional disks, and bridges contained between unequal disks. For the latter, we discuss both theoretical and experimental results. Finally, we present results concerning the stability of axisymmetric equilibrium configurations for a capillary liquid partly contained in a closed circular cylinder.

Near-Infrared Scintillation of Liquid Argon

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

Tilly, Elizabeth; Escobar, Carlos

2017-01-01

Liquid argon is well known to scintillate in the vacuum ultraviolet (VUV) range which is inherently difficult to detect. There has been recent evidence to suggest that it also emits near infrared (NIR) light. If this is the case, many large-scale time projection chambers and other similar detectors will be able to maximize light collection while minimizing cost. The goal of this project is to confirm and quantify this NIR emission. In order to accomplish this, an α-source was placed in a volume of highly purified liquid argon and observed using an infrared PMT with a filter excluding light withmore » wavelength <715 nm. Performing a simple counting experiment, there were indications of NIR scintillation. Further analysis is in progress.« less

High-Temperature Adiabatic Calorimeter for Constant-Volume Heat Capacity Measurements of Compressed Gases and Liquids

PubMed Central

Magee, Joseph W.; Deal, Renee J.; Blanco, John C.

1998-01-01

A high-temperature adiabatic calorimeter has been developed to measure the constant-volume specific heat capacities (cV) of both gases and liquids, especially fluids of interest to emerging energy technologies. The chief design feature is its nearly identical twin bomb arrangement, which allows accurate measurement of energy differences without large corrections for energy losses due to thermal radiation fluxes. Operating conditions for the calorimeter cover a range of temperatures from 250 K to 700 K and at pressures up to 20 MPa. Performance tests were made with a sample of twice-distilled water. Heat capacities for water were measured from 300 K to 420 K at pressures to 20 MPa. The measured heat capacities differed from those calculated with an independently developed standard reference formulation with a root-mean-square fractional deviation of 0.48 %. PMID:28009375

Study on fluid-structure interaction in liquid oxygen feeding pipe systems using finite volume method

NASA Astrophysics Data System (ADS)

Wei, Xin; Sun, Bing

2011-10-01

The fluid-structure interaction may occur in space launch vehicles, which would lead to bad performance of vehicles, damage equipments on vehicles, or even affect astronauts' health. In this paper, analysis on dynamic behavior of liquid oxygen (LOX) feeding pipe system in a large scale launch vehicle is performed, with the effect of fluid-structure interaction (FSI) taken into consideration. The pipe system is simplified as a planar FSI model with Poisson coupling and junction coupling. Numerical tests on pipes between the tank and the pump are solved by the finite volume method. Results show that restrictions weaken the interaction between axial and lateral vibrations. The reasonable results regarding frequencies and modes indicate that the FSI affects substantially the dynamic analysis, and thus highlight the usefulness of the proposed model. This study would provide a reference to the pipe test, as well as facilitate further studies on oscillation suppression.

Surface purity control during XMASS detector refurbishment

NASA Astrophysics Data System (ADS)

Kobayashi, Kazuyoshi

2015-08-01

The XMASS project aims at detecting dark matter, pp and 7Be solar neutrinos, and neutrino less double beta decay using large volume of pure liquid xenon. The first physics target of the XMASS project is to detect dark matter with 835 kg liquid xenon. After the commissioning runs, XMASS detector was refurbished to minimize the background contribution mainly from PMT sealing material and we restarted data taking in November 2013. We report how we control surface purity, especially how we prevent radon daughter accumulation on the detector copper surface, during XMASS detector refurbishment. The result and future plan of XMASS are also reported.

Measurement of Critical Contact Angle in a Microgravity Space Experiment

NASA Technical Reports Server (NTRS)

Concus, P.; Finn, R.; Weislogel, M.

1998-01-01

Mathematical theory predicts that small changes in container shape or in contact angle can give rise to large shifts of liquid in a microgravity environment. This phenomenon was investigated in the Interface Configuration Experiment on board the USML-2 Space Shuttle flight. The experiment's "double proboscis" containers were designed to strike a balance between conflicting requirements of sizable volume of liquid shift (for ease of observation) and abruptness of the shift (for accurate determination of critical contact angle). The experimental results support the classical concept of macroscopic contact angle and demonstrate the role of hysteresis in impeding orientation toward equilibrium.

Measurement of Critical Contact Angle in a Microgravity Space Experiment

NASA Technical Reports Server (NTRS)

Concus, P.; Finn, R.; Weislogel, M.

1998-01-01

Mathematical theory predicts that small changes in container shape or in contact angle can give rise to large shifts of liquid in a microgravity environment. This phenomenon was investigated in the Interface Configuration Experiment on board the USMT,2 Space Shuttle flight. The experiment's "double proboscis" containers were designed to strike a balance between conflicting requirements of sizable volume of liquid shift (for ease of observation) and abruptness of the shift (for accurate determination of critical contact angle). The experimental results support the classical concept of macroscopic contact angle and demonstrate the role of hysteresis in impeding orientation toward equilibrium.

Phase-Change Heat-Storage Module

NASA Technical Reports Server (NTRS)

Mulligan, James C.

1989-01-01

Heat-storage module accommodates momentary heating or cooling overload in pumped-liquid heat-transfer system. Large heat-storage capacity of module provided by heat of fusion of material that freezes at or near temperature desired to maintain object to be heated or cooled. Module involves relatively small penalties in weight, cost, and size and more than compensates by enabling design of rest of system to handle only average load. Latent heat of fusion of phase-change material provides large heat-storage capacity in small volume.

Direct Observation of Ion Distributions near Electrodes in Ionic Polymer Actuators Containing Ionic Liquids

PubMed Central

Liu, Yang; Lu, Caiyan; Twigg, Stephen; Ghaffari, Mehdi; Lin, Junhong; Winograd, Nicholas; Zhang, Q. M.

2013-01-01

The recent boom of energy storage and conversion devices, exploiting ionic liquids (ILs) to enhance the performance, requires an in-depth understanding of this new class of electrolytes in device operation conditions. One central question critical to device performance is how the mobile ions accumulate near charged electrodes. Here, we present the excess ion depth profiles of ILs in ionomer membrane actuators (Aquivion/1-butyl-2,3-dimethylimidazolium chloride (BMMI-Cl), 27 μm thick), characterized directly by Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) at liquid nitrogen temperature. Experimental results reveal that for the IL studied, cations and anions are accumulated at both electrodes. The large difference in the total volume occupied by the excess ions between the two electrodes cause the observed large bending actuation of the actuator. Hence we demonstrate that ToF-SIMS experiment provides great insights on the physics nature of ionic devices. PMID:23512124

40 CFR 799.2155 - Commercial hexane.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) “Commercial hexane,” for purposes of this section, is a product obtained from crude oil, natural gas liquids... least 40 liquid volume percent n-hexane (CAS No. 110-54-3) and at least 5 liquid volume percent... section, is a product which conforms to the specifications of ASTM D1836 and contains at least 40 liquid...

Theories of hydrophobic effects and the description of free volume in complex liquids

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

Pratt, L.R.; Garde, S.; Hummer, G.

1998-12-31

Recent progress on molecular theories of hydration of nonpolar solutes in liquid aqueous solution has lead to new ways to thinking about the old issue of free volume in liquids. This article surveys the principal new results with particular attention to the context of general issues of packing in liquids.

Elevated airway liquid volumes at birth: a potential cause of transient tachypnea of the newborn.

PubMed

McGillick, Erin V; Lee, Katie; Yamaoka, Shigeo; Te Pas, Arjan B; Crossley, Kelly J; Wallace, Megan J; Kitchen, Marcus J; Lewis, Robert A; Kerr, Lauren T; DeKoninck, Philip; Dekker, Janneke; Thio, Marta; McDougall, Annie R A; Hooper, Stuart B

2017-11-01

Excessive liquid in airways and/or distal lung tissue may underpin the respiratory morbidity associated with transient tachypnea of the newborn (TTN). However, its effects on lung aeration and respiratory function following birth are unknown. We investigated the effect of elevated airway liquid volumes on newborn respiratory function. Near-term rabbit kittens (30 days gestation; term ~32 days) were delivered, had their lung liquid-drained, and either had no liquid replaced (control; n = 7) or 30 ml/kg of liquid re-added to the airways [liquid added (LA); n = 7]. Kittens were mechanically ventilated in a plethysmograph. Measures of chest and lung parameters, uniformity of lung aeration, and airway size were analyzed using phase contrast X-ray imaging. The maximum peak inflation pressure required to recruit a tidal volume of 8 ml/kg was significantly greater in LA compared with control kittens (35.0 ± 0.7 vs. 26.8 ± 0.4 cmH 2 O, P < 0.001). LA kittens required greater time to achieve lung aeration (106 ± 14 vs. 60 ± 6 inflations, P = 0.03) and had expanded chest walls, as evidenced by an increased total chest area (32 ± 9%, P < 0.0001), lung height (17 ± 6%, P = 0.02), and curvature of the diaphragm (19 ± 8%, P = 0.04). LA kittens had lower functional residual capacity during stepwise changes in positive end-expiratory pressures (5, 3, 0, and 5 cmH 2 0). Elevated lung liquid volumes had marked adverse effects on lung structure and function in the immediate neonatal period and reduced the ability of the lung to aerate efficiently. We speculate that elevated airway liquid volumes may underlie the initial morbidity in near-term babies with TTN after birth. NEW & NOTEWORTHY Transient tachypnea of the newborn reduces respiratory function in newborns and is thought to result due to elevated airway liquid volumes following birth. However, the effect of elevated airway liquid volumes on neonatal respiratory function is unknown. Using phase contrast X-ray imaging, we show that elevated airway liquid volumes have adverse effects on lung structure and function in the immediate newborn period, which may underlie the pathology of TTN in near-term babies after birth. Copyright © 2017 the American Physiological Society.

On-demand generation and mixing of liquid-in-gas slugs with digitally-programmable composition and size

PubMed Central

Chen, Yi-Chun; Liu, Kan; Shen, Clifton Kwang-Fu; van Dam, R. Michael

2017-01-01

Microscopic droplets or slugs of mixed reagents provide a convenient platform for performing large numbers of isolated biochemical or chemical reactions for many screening and optimization applications. Myriad microfluidic approaches have emerged for creating droplets or slugs with controllable size and composition, generally using an immiscible carrier fluid to assist with the formation or merging processes. We report a novel device for generation of liquid slugs in air when the use of a carrier liquid is not compatible with the application. The slug generator contains two adjacent chambers, each of which has a volume that can be digitally adjusted by closing selected microvalves. Reagents are filled into the two chambers, merged together into a contiguous liquid slug, ejected at the desired time from the device using gas pressure, and mixed by flowing in a downstream channel. Programmable size and composition of slugs is achieved by dynamically adjusting the volume of each chamber prior to filling. Slug formation in this fashion is independent of fluid properties and can easily be scaled to mix larger numbers of reagents. This device has already been used to screen monomer ratios in supramolecular nanoparticle assembly and radiolabeling conditions of engineered antibodies, and here we provide a detailed description of the underlying device. PMID:29167603

Effect of pressure on viscosity of liquid Fe-alloys up to 16 GPa

NASA Astrophysics Data System (ADS)

Terasaki, H.; Ohtani, E.; Suzuki, A.; Nishida, K.; Sakamaki, T.; Shindo, S.; Funakoshi, K.

2005-12-01

Viscosity of liquid Fe-alloy is closely related to a convection behavior of the Earth's liquid outer core and also time scale of planetary core formation. In previous studies, viscosity of liquid Fe-S has been measured up to 7 GPa using X-ray radiography falling sphere method [Terasaki et al. 2001]. However, some technical problems, such as chemical reaction between the metal marker sphere and the Fe-alloy sample and insufficient image recording time for less viscous material, have been suggested. In this study, we have measured the viscosity of Fe-S and Fe-C liquids without those problems by using novel techniques combined with in situ X-ray radiography falling sphere method and extended the pressure range to 16 GPa. Falling sphere viscometry was carried out under high pressure and temperature using high speed CCD camera with 1500 ton Kawai-type multi-anvil device at BL04B1, SPring-8 in Japan. Starting compositions of Fe-alloy were Fe78S22 and Fe86C14 which correspond to near eutectic compositions at the experimental pressures. Viscosity marker sphere, which was made of Re or Pt, was coated by alumina in order to prevent the reaction between the sphere and the Fe-alloy sample. Falling sphere images were obtained with recording rate of 50 - 125 frame/second. Viscosity of liquid Fe-S was measured up to 16.1 GPa and 1763 K. Measured viscosity coefficients were in the range of 8.8 - 9.2 mPa-s which indicates that the activation volume of viscous flow is approximately a half of the previous estimations (1.5 cm3/mol). Viscosity of liquid Fe-C was measured up to 5 GPa and 1843 K. Viscosity coefficients are 4.7 - 4.9 mPa-s. Activation volume of Fe-C liquid is estimated to be 0.8 cm3/mol. This pressure dependence is consistent with the result of Lucas (1964) measured at ambient pressure. Consequently, viscosity of Fe-alloy liquids are likely to stay small in the Earth's interior and there is no large difference in viscosity coefficient and activation volume between Fe-S and Fe-C eutectic liquids in the range of measurements.

Tank gauging apparatus and method

NASA Technical Reports Server (NTRS)

Morris, Brian G. (Inventor)

1990-01-01

An apparatus for gauging the amount of liquid in a container of liquid and gas under low or zero gravity net conditions includes an accumulator and appropriate connector apparatus for communicating gas between the accumulator and the container. In one form of the invention, gas is removed from the container and compressed into the accumulator. The pressure and temperature of the fluid in the container is measured before and after removal of the gas; the pressure and temperature of the gas in the accumulator is measured before and after compression of the gas into the accumulator from the container. These pressure and temperature measurements are used to determine the volume of gas in the container, whereby the volume of the liquid in the container can be determined from the difference between the known volume of the container and the volume of gas in the container. Gas from the accumulator may be communicated into the container in a similar process as a verification of the gauging of the liquid volume, or as an independent process for determining the volume of liquid in the container.

Tank gauging apparatus and method

NASA Technical Reports Server (NTRS)

Morris, Brian G. (Inventor)

1991-01-01

Apparatus for gauging the amount of liquid in a container of liquid and gas under flow or zero gravity net conditions includes an accumulator and appropriate connector apparatus for communicating gas between the accumulator and the container. In one form of the invention, gas is removed from the container and compressed into the accumulator. The pressure and temperature of the fluid in the container is measured before and after removal of the gas; the pressure and temperature of gas in the accumulator is measured before and after compression of the gas into the accumulator from the container. These pressure and temperature measurements are used in determining the volume of gas in the container, whereby the volume of liquid in the container can be determined from the difference between the known volume of the container and the volume of gas in the container. Gas from the accumulator may be communicated into the container in a similar process as a verification of the gauging of the liquid volume, or as an independent process for determining the volume of liquid in the container.

Microscopic structural change in a liquid Fe-C alloy of ~5 GPa

DOE PAGES

Shibazaki, Yuki; Kono, Yoshio; Fei, Yingwei

2015-07-04

The structure of a liquid Fe-3.5 wt% C alloy is examined for up to 7.2 GPa via multiangle energy-dispersive X-ray diffraction using a Paris-Edinburgh type large-volume press. X-ray diffraction data show clear changes in the pressure-dependent peak positions of structure factor and reduced pair distribution function at 5GPa. These results suggest that the liquid Fe-3.5wt%C alloys change structurally at approximately 5GPa. This finding serves as a microscopic explanation for the alloy’s previously observed density change at the same pressure. The pressure dependencies of the nearest and second neighbor distances of the liquid Fe-3.5 wt% C alloy are similar to thosemore » of liquid Fe which exhibits a structural change near the bcc-fcc-liquid triple point (5.2GPa and 1991 K). Here, similarities between Fe-3.5wt% C and Fe suggest that a density change also occurs in liquid Fe and that this structural change extends to other Fe-light element alloys.« less

Puddle Jumping

NASA Astrophysics Data System (ADS)

Wollman, Andrew; Snyder, Trevor; Weislogel, Mark

2014-11-01

Rebounding droplets from superhydrophobic surfaces have attracted significant public and scientific attention because they are both enjoyable as well as industrially relevant. Demonstrations of bouncing droplets with volumes between 0.003 and 0.03 ml are common in the literature and limited primarily by gravity. In this presentation we demonstrate large droplet ``rebounds'' made possible by low-gravity testing in a drop tower. The up to 300 ml drops are best described as puddles that launch in a nearly identical manner to rebounding drops 4 orders of magnitude smaller in volume. A variety of jumping liquid and gas puddles are shown including puddles of highly specified and unusual initial geometry. The large length sales of the capillary fluidic surfaces ~ O (10 cm) enable 3D printing of all superhydrophobic surface topologies demonstrated. In addition, we demonstrate such puddle jumping as a passive drop-on-demand technique for large low-gravity drop dynamics investigations; such as collisions, rebounds, heat and mass transfer, and containerless possessing.

Liquid Crystalline Polymers

DTIC Science & Technology

1990-02-28

include energy costs, time required for cooling, large volume changes, and degradation. For many high -temperature LCPs, the latter may be the most...LCPs)- high local (microscopic) orientational order, which is retained in the solid state-has significant implications in a range of DOD applications...that yield and maintain specific mer sequences. * Continue efforts to measure mer sequence distribution, e.g., by multinuclei NMR. 0 Develop high

The DTIC Review: Volume 2, Number 4, Surviving Chemical and Biological Warfare

DTIC Science & Technology

1996-12-01

CHROMATOGRAPHIC ANALYSIS, NUCLEAR MAGNETIC RESONANCE, INFRARED SPECTROSCOPY , ARMY RESEARCH, DEGRADATION, VERIFICATION, MASS SPECTROSCOPY , LIQUID... mycotoxins . Such materials are not attractive as weapons of mass destruction however, as large amounts are required to produce lethal effects. In...VERIFICATION, ATOMIC ABSORPTION SPECTROSCOPY , ATOMIC ABSORPTION. AL The DTIC Review Defense Technical Information Center AD-A285 242 AD-A283 754 EDGEWOOO

Analysis of Androgenic Steroids in Environmental Waters by Large-volume Injection Liquid Chromatography Tandem Mass Spectrometry

PubMed Central

Backe, Will J.; Ort, Christoph; Brewer, Alex J.; Field, Jennifer A.

2014-01-01

A new method was developed for the analysis of natural and synthetic androgenic steroids and their selected metabolites in aquatic environmental matrices using direct large-volume injection (LVI) high performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS). Method accuracy ranged from 88 to 108% for analytes with well-matched internal standards. Precision, quantified by relative standard deviation (RSD), was less than 12%. Detection limits for the method ranged from 1.2 to 360 ng/L. The method was demonstrated on a series of 1-hr composite wastewater influent samples collected over a day with the purpose of assessing temporal profiles of androgen loads in wastewater. Testosterone, androstenedione, boldenone, and nandrolone were detected in the sample series at concentrations up to 290 ng/L and loads up to 535 mg. Boldenone, a synthetic androgen, had a temporal profile that was strongly correlated to testosterone, a natural human androgen, suggesting its source may be endogenous. An analysis of the sample particulate fraction revealed detectable amounts of sorbed testosterone and androstenedione. Androstenedione sorbed to the particulate fraction accounted for an estimated five to seven percent of the total androstenedione mass. PMID:21391574

Analysis of androgenic steroids in environmental waters by large-volume injection liquid chromatography tandem mass spectrometry.

PubMed

Backe, Will J; Ort, Christoph; Brewer, Alex J; Field, Jennifer A

2011-04-01

A new method was developed for the analysis of natural and synthetic androgenic steroids and their selected metabolites in aquatic environmental matrixes using direct large-volume injection (LVI) high-performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS). Method accuracy ranged from 87.6 to 108% for analytes with well-matched internal standards. Precision, quantified by relative standard deviation (RSD), was less than 12%. Detection limits for the method ranged from 1.2 to 360 ng/L. The method was demonstrated on a series of 1 h composite wastewater influent samples collected over a day with the purpose of assessing temporal profiles of androgen loads in wastewater. Testosterone, androstenedione, boldenone, and nandrolone were detected in the sample series at concentrations up to 290 ng/L and loads up to 535 mg/h. Boldenone, a synthetic androgen, had a temporal profile that was strongly correlated to testosterone, a natural human androgen, suggesting its source may be endogenous. An analysis of the sample particulate fraction revealed detectable amounts of sorbed testosterone and androstenedione. Androstenedione sorbed to the particulate fraction accounted for an estimated 5 to 7% of the total androstenedione mass.

Analysis of iodinated haloacetic acids in drinking water by reversed-phase liquid chromatography/electrospray ionization/tandem mass spectrometry with large volume direct aqueous injection.

PubMed

Li, Yongtao; Whitaker, Joshua S; McCarty, Christina L

2012-07-06

A large volume direct aqueous injection method was developed for the analysis of iodinated haloacetic acids in drinking water by using reversed-phase liquid chromatography/electrospray ionization/tandem mass spectrometry in the negative ion mode. Both the external and internal standard calibration methods were studied for the analysis of monoiodoacetic acid, chloroiodoacetic acid, bromoiodoacetic acid, and diiodoacetic acid in drinking water. The use of a divert valve technique for the mobile phase solvent delay, along with isotopically labeled analogs used as internal standards, effectively reduced and compensated for the ionization suppression typically caused by coexisting common inorganic anions. Under the optimized method conditions, the mean absolute and relative recoveries resulting from the replicate fortified deionized water and chlorinated drinking water analyses were 83-107% with a relative standard deviation of 0.7-11.7% and 84-111% with a relative standard deviation of 0.8-12.1%, respectively. The method detection limits resulting from the external and internal standard calibrations, based on seven fortified deionized water replicates, were 0.7-2.3 ng/L and 0.5-1.9 ng/L, respectively. Copyright © 2012 Elsevier B.V. All rights reserved.

High-sensitivity direct analysis of aflatoxins in peanuts and cereal matrices by ultra-performance liquid chromatography with fluorescence detection involving a large volume flow cell.

PubMed

Oulkar, Dasharath; Goon, Arnab; Dhanshetty, Manisha; Khan, Zareen; Satav, Sagar; Banerjee, Kaushik

2018-04-03

This paper reports a sensitive and cost effective method of analysis for aflatoxins B1, B2, G1 and G2. The sample preparation method was primarily optimised in peanuts, followed by its validation in a range of peanut-processed products and cereal (rice, corn, millets) matrices. Peanut slurry [12.5 g peanut + 12.5 mL water] was extracted with methanol: water (8:2, 100 mL), cleaned through an immunoaffinity column and thereafter measured directly by ultra-performance liquid chromatography-fluorescence (UPLC-FLD) detection, within a chromatographic runtime of 5 minutes. The use of a large volume flow cell in the FLD nullified the requirement of any post-column derivatisation and provided the lowest ever reported limits of quantification of 0.025 for B1 and G1 and 0.01 μg/kg for B2 and G2. The single laboratory validation of the method provided acceptable selectivity, linearity, recovery and precision for reliable quantifications in all the test matrices as well as demonstrated compliance with the EC 401/2006 guidelines for analytical quality control of aflatoxins in foodstuffs.

Group extraction of organic compounds present in liquid samples

NASA Technical Reports Server (NTRS)

Jahnsen, Vilhelm J. (Inventor)

1976-01-01

An extraction device is disclosed comprising a tube containing a substantially inert, chemically non-reactive packing material with a large surface area to volume ratio. A sample which consists of organic compounds dissolved in a liquid, is introduced into the tube. As the sample passes through the packing material it spreads over the material's large surface area to form a thin liquid film which is held on the packing material in a stationary state. A particular group or family of compounds is extractable from the sample by passing a particular solvent system consisting of a solvent and selected reagents through the packing material. The reagents cause optimum conditions to exist for the compounds of the particular family to pass through the phase boundary between the sample liquid and the solvent of the solvent system. Thus, the compounds of the particular family are separated from the sample liquid and become dissolved in the solvent of the solvent system. The particular family of compounds dissolved in the solvent, representing an extract, exits the tube together with the solvent through the tube's nozzle, while the rest of the sample remains on the packing material in a stationary state. Subsequently, a different solvent system may be passed through the packing material to extract another family of compounds from the remaining sample on the packing material.

Liquid fractionation. Part I: Basic principles and experimental simulations

NASA Astrophysics Data System (ADS)

McBirney, Alexander R.; Baker, Brian H.; Nilson, Robert H.

1985-03-01

A possible explanation for the closely associated magmas of contrasting compositions erupted from many mature volcanic centers can be found in the large differences of density produced by relatively small compositional variations in liquids that evolve by crystallization or melting at the walls of shallow magma chambers. A mechanism of liquid fractionation in which differentiated liquids segragate gravitationally to form compositionally graded columns of magma may surmount the long-standing problem of explaining large volumes of highly evolved liquids that reach advanced degrees of differentiation in times that are too short to be consistent with conventional models of crystal fractionation based on crystal settling. In those types of magmas that decrease in density as they differentiate, a fractionated liquid next to a wall may form a buoyant compositional boundary layer that flows up the wall and accumulates as a separate zone in the upper levels of the reservoir. Magmas that increase in density as they differentiate will have the opposite behavior; they descend along the wall and pond on the floor. Both types of systems can be modeled using simple aqueous solutions and techniques similar to those developed by Chen and Turner (1980). The insights gained through experiments of this kind suggest a number of processes that may be responsible for common types of volcanic behavior and patterns of differentiation in shallow plutons.

Magma Reservoirs from the Perspective of Supervolcanoes and Granitic Plutons: "Big Red Blobs" and "Balloons and Soda Straws" are Real

NASA Astrophysics Data System (ADS)

Christiansen, E. H.

2016-12-01

Simple models describing silicic magma reservoirs and their connections with volcanic rocks have been denigrated as "big red blobs" and "balloons-and-soda straws." Although these models are certainly generalized to convey complex relations, there are multiple reasons to accept the existence of large magma chambers and direct connections between volcanoes and plutonic rocks. These include:-Geophysical evidence (seismic, magnetotelluric, and geodetic) for the existence of large bodies of magma in the crust today. Magma is a mixture of liquids, solids, and fluids. It does not have to be melt rich, nor does it need to be mobile and eruptible; it just has to have melt present. -Eruptions of large volumes (>1,000 km3) of dacitic to rhyolitic magma and large collapse calderas (30-50 km across). -The thermal lifetimes of large bodies are extended by high recharge rates. Individual bodies of magma may exist for tens to hundreds of thousands of years.-Geochronological evidence that pluton lifetimes are similar to those of volcanic fields.-Evidence for incremental emplacement of a pluton is not evidence against the former existence of a large magma reservoir, but the natural consequence of ongoing replenishment and crystallization after eruptions cease. Thus, what might have been a large liquid-dominated system at the time of eruption of a large ignimbrite, is subsequently intruded by new batches of magma as it crystallizes and closes down. This destroys the evidence for a large red blob and creates a composite pluton. -Direct and indirect evidence connect plutons to large eruptions. This is shown by field relations, geochronology, as well as chemical, mineralogical, and isotopic similarities of volcanic and plutonic rocks. -Volcanic and plutonic differentiation patterns are very similar, but differ in some ways because cumulates are preserved in the plutonic record and because intrusions continue to differentiate (liquids separate from solids) until the last bit of liquid is consumed. Highly evolved liquids are present in the volcanic record, but are less common than in intrusions. Most plutonic rocks appear to be mixtures of cumulate minerals and interstitial melt unable to separate from the coarsening mush.

Radiofrequency ablation during continuous saline infusion can extend ablation margins

PubMed Central

Ishikawa, Toru; Kubota, Tomoyuki; Horigome, Ryoko; Kimura, Naruhiro; Honda, Hiroki; Iwanaga, Akito; Seki, Keiichi; Honma, Terasu; Yoshida, Toshiaki

2013-01-01

AIM: To determine whether fluid injection during radiofrequency ablation (RFA) can increase the coagulation area. METHODS: Bovine liver (1-2 kg) was placed on an aluminum tray with a return electrode affixed to the base, and the liver was punctured by an expandable electrode. During RFA, 5% glucose; 50% glucose; or saline fluid was infused continuously at a rate of 1.0 mL/min through the infusion line connected to the infusion port. The area and volume of the thermocoagulated region of bovine liver were determined after RFA. The Joule heat generated was determined from the temporal change in output during the RFA experiment. RESULTS: No liquid infusion was 17.3 ± 1.6 mL, similar to the volume of a 3-cm diameter sphere (14.1 mL). Mean thermocoagulated volume was significantly larger with continuous infusion of saline (29.3 ± 3.3 mL) than with 5% glucose (21.4 ± 2.2 mL), 50% glucose (16.5 ± 0.9 mL) or no liquid infusion (17.3 ± 1.6 mL). The ablated volume for RFA with saline was approximately 1.7-times greater than for RFA with no liquid infusion, representing a significant difference between these two conditions. Total Joule heat generated during RFA was highest with saline, and lowest with 50% glucose. CONCLUSION: RFA with continuous saline infusion achieves a large ablation zone, and may help inhibit local recurrence by obtaining sufficient ablation margins. RFA during continuous saline infusion can extend ablation margins, and may be prevent local recurrence. PMID:23483097

Effects of solution volume on hydrogen production by pulsed spark discharge in ethanol solution

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

Xin, Y. B.; Sun, B., E-mail: sunb88@dlmu.edu.cn; Zhu, X. M.

2016-07-15

Hydrogen production from ethanol solution (ethanol/water) by pulsed spark discharge was optimized by varying the volume of ethanol solution (liquid volume). Hydrogen yield was initially increased and then decreased with the increase in solution volume, which achieved 1.5 l/min with a solution volume of 500 ml. The characteristics of pulsed spark discharge were studied in this work; the results showed that the intensity of peak current, the rate of current rise, and energy efficiency of hydrogen production can be changed by varying the volume of ethanol solution. Meanwhile, the mechanism analysis of hydrogen production was accomplished by monitoring the process of hydrogenmore » production and the state of free radicals. The analysis showed that decreasing the retention time of gas production and properly increasing the volume of ethanol solution can enhance the hydrogen yield. Through this research, a high-yield and large-scale method of hydrogen production can be achieved, which is more suitable for industrial application.« less

Measurement of gastric meal and secretion volumes using magnetic resonance imaging

PubMed Central

Hoad, C.L.; Parker, H.; Hudders, N.; Costigan, C.; Cox, E.F.; Perkins, A.C.; Blackshaw, P.E.; Marciani, L.; Spiller, R.C.; Fox, M.R.; Gowland, P.A.

2015-01-01

MRI can assess multiple gastric functions without ionizing radiation. However, time consuming image acquisition and analysis of gastric volume data, plus confounding of gastric emptying measurements by gastric secretions mixed with the test meal have limited its use to research centres. This study presents an MRI acquisition protocol and analysis algorithm suitable for the clinical measurement of gastric volume and secretion volume. Reproducibility of gastric volume measurements was assessed using data from 10 healthy volunteers following a liquid test meal with rapid MRI acquisition within one breath-hold and semi-automated analysis. Dilution of the ingested meal with gastric secretion was estimated using a respiratory-triggered T1 mapping protocol. Accuracy of the secretion volume measurements was assessed using data from 24 healthy volunteers following a mixed (liquid/solid) test meal with MRI meal volumes compared to data acquired using gamma scintigraphy (GS) on the same subjects studied on a separate study day. The mean (SD) coefficient of variance between 3 observers for both total gastric contents (including meal, secretions and air) and just the gastric contents (meal and secretion only) was 3 (2) % at large gastric volumes (> 200 ml). Mean (SD) secretion volumes post meal ingestion were 64 (51) ml and 110 (40) ml at 15 and 75 minutes respectively. Comparison with GS meal volumes, showed that MRI meal only volume (after correction for secretion volume) were similar to GS, with a linear regression gradient (std err) of 1.06 (0.10) and intercept −11 (24) ml. In conclusion, (i) rapid acquisition removed the requirement to image during prolonged breath-hold (ii) semi-automatic analysis greatly reduced time required to derive measurements and (iii) correction for secretion volumes provides accurate assessment of gastric meal volumes and emptying. Together these features provide the scientific basis of a protocol which would be suitable in clinical practice. PMID:25592405

A new approach to determine the density of liquids and solids without measuring mass and volume: introducing the solidensimeter

NASA Astrophysics Data System (ADS)

Kiriktaş, Halit; Şahin, Mehmet; Eslek, Sinan; Kiriktaş, İrem

2018-05-01

This study aims to design a mechanism with which the density of any solid or liquid can be determined without measuring its mass and volume in order to help students comprehend the concept of density more easily. The solidensimeter comprises of two scaled and nested glass containers (graduated cylinder or beaker) and sufficient water. In this method, the density measurement was made using the Archimedes’ principle stating that an object fully submerged in a liquid displaces the same amount of liquid as its volume, while an object partially submerged or floating displaces the same amount of liquid as its mass. Using this method, the density of any solids or liquids can be determined using a simple mathematical ratio. At the end of the process a mechanism that helps students to comprehend the density topic more easily was designed. The system is easy-to-design, uses low-cost equipment and enables one to determine the density of any solid or liquid without measuring its mass and volume.

Some new features of Direct Analysis in Real Time mass spectrometry utilizing the desorption at an angle option.

PubMed

Chernetsova, Elena S; Revelsky, Alexander I; Morlock, Gertrud E

2011-08-30

The present study is a first step towards the unexplored capabilities of Direct Analysis in Real Time (DART) mass spectrometry (MS) arising from the possibility of the desorption at an angle: scanning analysis of surfaces, including the coupling of thin-layer chromatography (TLC) with DART-MS, and a more sensitive analysis due to the preliminary concentration of analytes dissolved in large volumes of liquids on glass surfaces. In order to select the most favorable conditions for DART-MS analysis, proper positioning of samples is important. Therefore, a simple and cheap technique for the visualization of the impact region of the DART gas stream onto a substrate was developed. A filter paper or TLC plate, previously loaded with the analyte, was immersed in a derivatization solution. On this substrate, owing to the impact of the hot DART gas, reaction of the analyte to a colored product occurred. An improved capability of detection of DART-MS for the analysis of liquids was demonstrated by applying large volumes of model solutions of coumaphos into small glass vessels and drying these solutions prior to DART-MS analysis under ambient conditions. This allowed the introduction of, by up to more than two orders of magnitude, increased quantities of analyte compared with the conventional DART-MS analysis of liquids. Through this improved detectability, the capabilities of DART-MS in trace analysis could be strengthened. Copyright © 2011 John Wiley & Sons, Ltd.

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

Wu, H.L.; Spronsen, G. van; Klaus, E.H.

A simulation model of the dynamics of a by-pass pig and related two-phase flow behavior along with field trials of the pig in a dry-gas pipeline have revealed significant gains in use of a by-pass pig in modifying gas and liquid production rates. The method can widen the possibility of applying two-phase flow pipeline transportation to cases in which separator or slug-catcher capacity is limited by practicality or cost. Pigging two-phase pipelines normally generates large liquid slug volumes in front of the pig. These require large separators or slug catchers. Using a high by-pass pig to disperse the liquid andmore » reduce the maximum liquid production rate before pig arrival has been investigated by Shell Exploration and Production companies. A simulation model of the dynamics of the pig and related two-phase flow behavior in the pipeline was used to predict the performance of by-pass pigs. Field trials in a dry-gas pipeline were carried out to provide friction data and to validate the model. The predicted mobility of the high by-pass pig in the pipeline and risers was verified and the beneficial effects due to the by-pass concept exceeded the prediction of the simplified model.« less

Preconcentration of aqueous dyes through phase-transfer liquid-phase microextraction with a room-temperature ionic liquid.

PubMed

Chen, Hsiu-Liang; Chang, Shuo-Kai; Lee, Chia-Ying; Chuang, Li-Lin; Wei, Guor-Tzo

2012-09-12

In this study, we employed the room-temperature ionic liquid [bmim][PF(6)] as both ion-pair agent and an extractant in the phase-transfer liquid-phase microextraction (PTLPME) of aqueous dyes. In the PTLPME method, a dye solution was added to the extraction solution, comprising a small amount of [bmim][PF(6)] in a relatively large amount of CH(2)Cl(2), which serves as the disperser solvent to an extraction solution. Following extraction, CH(2)Cl(2) was evaporated from the extractant, resulting in the extracted dyes being concentrated in a small volume of the ionic liquid phase to increase the enrichment factor. The enrichment factors of for the dye Methylene Blue, Neutral Red, and Methyl Red were approximately 500, 550 and 400, respectively; their detection limits were 0.014, 0.43, and 0.02 μg L(-1), respectively, with relative standard deviations of 4.72%, 4.20%, and 6.10%, respectively. Copyright © 2012 Elsevier B.V. All rights reserved.

Pleural liquid and its exchanges.

PubMed

Agostoni, Emilio; Zocchi, Luciano

2007-12-15

After an account on morphological features of visceral and parietal pleura, mechanical coupling between lung and chest wall is outlined. Volume of pleural liquid is considered along with its thickness in various regions, and its composition. Pleural liquid pressure (P(liq)) and pressure exerted by lung recoil in various species and postures are then compared, and the vertical gradient of P(liq) considered. Implications of lower P(liq) in the lung zone than in the costo-phrenic sinus at iso-height are pointed out. Mesothelial permeability to H(2)O, Cl(-), Na(+), mannitol, sucrose, inulin, albumin, and various size dextrans is provided, along with paracellular "pore" radius of mesothelium. Pleural liquid is produced by filtration from parietal pleura capillaries according to Starling forces. It is removed by absorption in visceral pleura capillaries according to Starling forces (at least in some species), lymphatic drainage through stomata of parietal mesothelium (essential to remove cells, particles, and large macromolecules), solute-coupled liquid absorption, and transcytosis through mesothelium.

78 FR 35996 - Self-Regulatory Organizations; EDGX Exchange, Inc.; Notice of Filing and Immediate Effectiveness...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-14

... liquidity; (5) add the Midpoint Match Volume Tier (``MPM Volume Tier'') to Footnote 3 of the Exchange's fee... add liquidity to the Exchange absent Members qualifying for additional volume tiered pricing. \\5... average daily volume (``ADV'') to EDGX, then the Member would get the current rate of $0.0001 per share...

Measuring refractive index and volume of liquid under high pressure with optical coherence tomography and light microscopy.

PubMed

Wang, Donglin; Yang, Kun; Zhou, Yin

2016-03-20

Measuring the refractive index and volume of liquid under high pressure simultaneously is a big challenge. This paper proposed an alternative solution by combing optical coherence tomography with microscopy. An experiment for a feasibility study was carried out on polydimethylsiloxane liquid in a diamond anvil cell. The refractive index of the sample increased dramatically with pressure loaded, and the curve of pressure volume was also obtained.

A laboratory method for precisely determining the micro-volume-magnitudes of liquid efflux

NASA Technical Reports Server (NTRS)

Cloutier, R. L.

1969-01-01

Micro-volumetric quantities of ejected liquid are made to produce equal volumetric displacements of a more dense material. Weight measurements are obtained on the displaced heavier liquid and used to calculate volumes based upon the known density of the heavy medium.

40 CFR 98.393 - Calculating GHG emissions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... from each individual petroleum product and natural gas liquid using Equation MM-1 of this section... of each petroleum product or natural gas liquid “i” (metric tons). Producti = Annual volume of... only includes products ex refinery gate. For natural gas liquids, volumes shall reflect the individual...

The Partial Molar Volume and Thermal Expansivity of Fe2O3 in Alkali Silicate Liquids: Evidence for the Average Coordination of Fe3+

NASA Astrophysics Data System (ADS)

Liu, Q.; Lange, R.

2003-12-01

Ferric iron is an important component in magmatic liquids, especially in those formed at subduction zones. Although it has long been known that Fe3+ occurs in four-, five- and six-fold coordination in crystalline compounds, only recently have all three Fe3+ coordination sites been confirmed in silicate glasses utilizing XANES spectroscopy at the Fe K-edge (Farges et al., 2003). Because the density of a magmatic liquid is largely determined by the geometrical packing of its network-forming cations (e.g., Si4+, Al3+, Ti4+, and Fe3+), the capacity of Fe3+ to undergo composition-induced coordination change affects the partial molar volume of the Fe2O3 component, which must be known to calculate how the ferric-ferrous ratio in magmatic liquids changes with pressure. Previous work has shown that the partial molar volume of Fe2O3 (VFe2O3) varies between calcic vs. sodic silicate melts (Mo et al., 1982; Dingwell and Brearley, 1988; Dingwell et al., 1988). The purpose of this study is to extend the data set in order to search for systematic variations in VFe2O3 with melt composition. High temperature (867-1534° C) density measurements were performed on eleven liquids in the Na2O-Fe2O3-FeO-SiO2 (NFS) system and five liquids in the K2O-Fe2O3-FeO-SiO2 (KFS) system using Pt double-bob Archimedean method. The ferric-ferrous ratio in the sodic and potassic liquids at each temperature of density measurement were calculated from the experimentally calibrated models of Lange and Carmichael (1989) and Tangeman et al. (2001) respectively. Compositions range (in mol%) from 4-18 Fe2O3, 0-3 FeO, 12-39 Na2O, 25-37 K2O, and 43-78 SiO2. Our density data are consistent with those of Dingwell et al. (1988) on similar sodic liquids. Our results indicate that for all five KFS liquids and for eight of eleven NFS liquids, the partial molar volume of the Fe2O3 component is a constant (41.57 ñ 0.14 cm3/mol) and exhibits zero thermal expansivity (similar to that for the SiO2 component). This value was obtained in a fit to a linear volume equation in which the other oxide components have the following fitted partial molar volumes (cm3/mol) at 1100° C: SiO2 = 26.85+/-0.04, Na2O = 26.57+/-0.07, K2O = 42.34+/-0.10, and FeO = 12.84+/-0.28, and the following fitted fitted partial molar thermal expansivities (10-3 cm3/mol-K): Na2O = 7.73+/-0.12, K2O = 11.99+/-0.24, and FeO = 2.88+/-1.22. For the three sodic liquids not included in this regression, the most iron-rich (18.2 mol% Fe2O3) has a value for VFe2O3 of 44.1 cm3/mole, whereas the most iron-poor (4.4 mol% Fe2O3) has a value for VFe2O3 of 37.0 cm3/mole. This trend may reflect a greater proportion of four-fold ferric iron in iron-rich liquids, which mirrors the trend of increasing ferric-ferrous ratios in sodic liquids as a function of total iron content (Lange and Carmichael, 1989). The most polymerized liquid in our data set was a sodic liquid that has a value for VFe2O3 of 45.0 cm3/mole. It thus appears that most (13 of 16) of our experimental liquids, which span a wide compositional range, lead to a VFe2O3 (41.6 cm3/mol) which is constant with composition and temperature. However, there are three important outliers that may have implications for the appropriate value to apply to magmatic liquids.

Paradoxes of thermodynamics of swelling equilibria of polymers in liquids and vapors.

PubMed

Davankov, Vadim A; Pastukhov, Alexander V

2011-12-29

An automatic registration of the changing size of a single spherical microbead of a cross-linked polymer was applied for studying the swelling process of the bead by the sorption of vapors and/or liquids. Many representatives of all three basic types of polymeric networks, gel-type, hypercrosslinked, and macroporous, were examined. Only the first two display large volume changes and prove suitable for following the kinetics and extent of swelling by the above dilatometric technique. The results unambiguously prove that swelling of all polymeric networks in liquids is always higher than in corresponding saturated vapors (Schroeder's paradox). The general nature of this phenomenon implies that the absolute activity of any sorbate in its liquid form is always larger than in the form of its saturated vapor. Surprisingly, gels with any solvent contents, which fall into the broad range between the vapor-equilibrated and liquid-equilibrated extreme contents, retain their volumes constant in the saturated vapor atmosphere. This paradox of a wide range of gels swollen to a different extent and, nevertheless, standing in equilibrium with saturated vapor is explained by the specificity of the network polymers, namely, that the energy of the solvent-polymer interactions is easily compensated by the energy of remaining between-chain interactions at any solvent content in the above range. Therefore, the strain-free swollen gels do not generate enhanced vapor pressure, but neither display the ability to take up more sorbate from its vapor. © 2011 American Chemical Society

Using Dalton's Law of Partial Pressures to Determine the Vapor Pressure of a Volatile Liquid

ERIC Educational Resources Information Center

Hilgeman, Fred R.; Bertrand, Gary; Wilson, Brent

2007-01-01

This experiment, designed for a general chemistry laboratory, illustrates the use of Dalton's law of partial pressures to determine the vapor pressure of a volatile liquid. A predetermined volume of air is injected into a calibrated tube filled with a liquid whose vapor pressure is to be measured. The volume of the liquid displaced is greater than…

The Specific Volumes and Viscosities of the Ni-Zr Liquid Alloys and their Correlation with the Glass Formability of the Alloys

NASA Technical Reports Server (NTRS)

Ohsaka, K.; Chung, S. K.; Rhim, W. K.

1997-01-01

The specific volumes and viscosities of the Ni-Zr liquid alloys as a function of temperature are determined by employing a digitizing technique and numeric analysis methods applied to the optical images of the electrostatically levitated liquid alloys.

40 CFR 799.2155 - Commercial hexane.

Code of Federal Regulations, 2010 CFR

2010-07-01

...,” for purposes of this section, is a product obtained from crude oil, natural gas liquids, or petroleum... (ASTM D 1836), consists primarily of six-carbon alkanes or cycloalkanes, and contains at least 40 liquid volume percent n-hexane (CAS No. 110-54-3) and at least 5 liquid volume percent methylcyclopentane (MCP...

40 CFR 98.393 - Calculating GHG emissions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... emissions from each individual petroleum product and natural gas liquid using Equation MM-1 of this section... of each petroleum product or natural gas liquid “i” (metric tons). Producti = Annual volume of... reported under § 98.396(a)(1). For natural gas liquids, volumes shall reflect the individual components of...

40 CFR 98.393 - Calculating GHG emissions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... emissions from each individual petroleum product and natural gas liquid using Equation MM-1 of this section... of each petroleum product or natural gas liquid “i” (metric tons). Producti = Annual volume of... reported under § 98.396(a)(2). For natural gas liquids, volumes shall reflect the individual components of...

40 CFR 98.393 - Calculating GHG emissions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... emissions from each individual petroleum product and natural gas liquid using Equation MM-1 of this section... of each petroleum product or natural gas liquid “i” (metric tons). Producti = Annual volume of... reported under § 98.396(a)(1). For natural gas liquids, volumes shall reflect the individual components of...

40 CFR 98.393 - Calculating GHG emissions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... emissions from each individual petroleum product and natural gas liquid using Equation MM-1 of this section... of each petroleum product or natural gas liquid “i” (metric tons). Producti = Annual volume of... reported under § 98.396(a)(1). For natural gas liquids, volumes shall reflect the individual components of...

A reversible transition in liquid Bi under pressure.

PubMed

Emuna, M; Matityahu, S; Yahel, E; Makov, G; Greenberg, Y

2018-01-21

The electrical resistance of solid and liquid Bi has been measured at high pressures and temperatures using a novel experimental design for high sensitivity measurements utilizing a "Paris-Edinburgh" toroid large volume press. An anomalous sharp decrease in resistivity with increasing temperature at constant pressures was observed in the region beyond melting which implies a possible novel transition in the melt. The proposed transition was observed across a range of pressures both in heating and cooling cycles of the sample demonstrating its reversibility. From the measurements it was possible to determine a "phase-line" of this transition on the Bi pressure-temperature phase diagram terminating at the melting curve.

Titan's inventory of organic surface materials

USGS Publications Warehouse

Lorenz, R.D.; Mitchell, K.L.; Kirk, R.L.; Hayes, A.G.; Aharonson, O.; Zebker, H.A.; Paillou, P.; Radebaugh, J.; Lunine, J.I.; Janssen, M.A.; Wall, S.D.; Lopes, R.M.; Stiles, B.; Ostro, S.; Mitri, Giuseppe; Stofan, E.R.

2008-01-01

Cassini RADAR observations now permit an initial assessment of the inventory of two classes, presumed to be organic, of Titan surface materials: polar lake liquids and equatorial dune sands. Several hundred lakes or seas have been observed, of which dozens are each estimated to contain more hydrocarbon liquid than the entire known oil and gas reserves on Earth. Dark dunes cover some 20% of Titan's surface, and comprise a volume of material several hundred times larger than Earth's coal reserves. Overall, however, the identified surface inventories (>3 ?? 104 km3 of liquid, and >2 ?? 105 km3 of dune sands) are small compared with estimated photochemical production on Titan over the age of the solar system. The sand volume is too large to be accounted for simply by erosion in observed river channels or ejecta from observed impact craters. The lakes are adequate in extent to buffer atmospheric methane against photolysis in the short term, but do not contain enough methane to sustain the atmosphere over geologic time. Unless frequent resupply from the interior buffers this greenhouse gas at exactly the right rate, dramatic climate change on Titan is likely in its past, present and future. Copyright 2008 by the American Geophysical Union.

Hydrodynamics of the Fluid Filtrate on Drilling-In

NASA Astrophysics Data System (ADS)

Abbasov, É. M.; Agaeva, N. A.

2014-01-01

The volume of the liquid penetrating into the formation after drilling-in has been determined on the basis of theoretical investigations. The dynamics of change in the bottom-hole pressure has been determined in this process. It has been shown that because of the water hammer, the bottom-hole pressure can be doubled in the presence of large fractures and pores closer to the well-bottom zone.

Theoretical analysis of mixing in liquid clouds – Part 3: Inhomogeneous mixing

DOE PAGES

Pinsky, Mark; Khain, Alexander; Korolev, Alexei

2016-07-28

An idealized diffusion–evaporation model of time-dependent mixing between a cloud volume and a droplet-free volume is analyzed. The initial droplet size distribution (DSD) in the cloud volume is assumed to be monodisperse. It is shown that evolution of the microphysical variables and the final equilibrium state are unambiguously determined by two non-dimensional parameters. The first one is the potential evaporation parameter R, proportional to the ratio of the saturation deficit to the liquid water content in the cloud volume, that determines whether the equilibrium state is reached at 100 % relative humidity, or is characterized by a complete evaporation ofmore » cloud droplets. The second parameter Da is the Damkölher number equal to the ratio of the characteristic mixing time to the phase relaxation time. Parameters R and Da determine the type of mixing. The results are analyzed within a wide range of values of R and Da. It is shown that there is no pure homogeneous mixing, since the first mixing stage is always inhomogeneous. The mixing type can change during the mixing process. Any mixing type leads to formation of a tail of small droplets in DSD and, therefore, to DSD broadening that depends on Da. At large Da, the final DSD dispersion can be as large as 0.2. The total duration of mixing varies from several to 100 phase relaxation time periods, depending on R and Da. The definitions of homogeneous and inhomogeneous types of mixing are reconsidered and clarified, enabling a more precise delimitation between them. The paper also compares the results obtained with those based on the classic mixing concepts.« less

Theoretical analysis of mixing in liquid clouds – Part 3: Inhomogeneous mixing

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

Pinsky, Mark; Khain, Alexander; Korolev, Alexei

An idealized diffusion–evaporation model of time-dependent mixing between a cloud volume and a droplet-free volume is analyzed. The initial droplet size distribution (DSD) in the cloud volume is assumed to be monodisperse. It is shown that evolution of the microphysical variables and the final equilibrium state are unambiguously determined by two non-dimensional parameters. The first one is the potential evaporation parameter R, proportional to the ratio of the saturation deficit to the liquid water content in the cloud volume, that determines whether the equilibrium state is reached at 100 % relative humidity, or is characterized by a complete evaporation ofmore » cloud droplets. The second parameter Da is the Damkölher number equal to the ratio of the characteristic mixing time to the phase relaxation time. Parameters R and Da determine the type of mixing. The results are analyzed within a wide range of values of R and Da. It is shown that there is no pure homogeneous mixing, since the first mixing stage is always inhomogeneous. The mixing type can change during the mixing process. Any mixing type leads to formation of a tail of small droplets in DSD and, therefore, to DSD broadening that depends on Da. At large Da, the final DSD dispersion can be as large as 0.2. The total duration of mixing varies from several to 100 phase relaxation time periods, depending on R and Da. The definitions of homogeneous and inhomogeneous types of mixing are reconsidered and clarified, enabling a more precise delimitation between them. The paper also compares the results obtained with those based on the classic mixing concepts.« less

Electrowetting-based optics

NASA Astrophysics Data System (ADS)

Kuiper, S.; Hendriks, B. H. W.; Hayes, R. A.; Feenstra, B. J.; Baken, J. M. E.

2005-09-01

Electrowetting is electrostatic manipulation of liquids. It can be used to displace and deform volumes of polar liquids. A very promising application area is optics. The surface of a volume of liquid can be used as a tunable lens and displacement of the liquid can change the refraction, diffraction or transmission of light when passing through the liquid. In this paper we describe a selection of various tunable optical components that make use of electrowetting, ranging from refractive and diffractive lenses to diaphragms and displays.

Magnetic particles as liquid carriers in the microfluidic lab-in-tube approach to detect phase change.

PubMed

Blumenschein, Nicholas A; Han, Daewoo; Caggioni, Marco; Steckl, Andrew J

2014-06-11

Magnetic beads (MBs) with ∼1.9 μm average diameter were used to transport specific microliter-scale volumes of liquids between adjacent reservoirs within a closed tube under the influence of a magnetic field. The tube's inner surface is coated with a hydrophobic layer, enabling the formation of a surface tension valve by inserting an air gap between reservoirs. This transfer process was implemented by keeping the MBs stationary with a fixed external magnet while the liquid reservoirs were translated by a computer-controlled syringe pump system. The magnet induces the aggregation of MBs in a loosely packed cluster (void volume ∼90-95%) against the tube's inner wall. The liquid trapped in the MB cluster is transported across the air gap between reservoirs. Fluorescence intensity from a dye placed in one reservoir is used to measure the volume of liquid transferred between reservoirs. The carry-over liquid volume is controlled by the mass of the MBs within the device. The typical volume of liquid carried by the MB cluster is ∼2 to 3 μL/mg of beads, allowing the use of small samples. This technique can be used to study the effect of small compositional variation on the properties of fluid mixtures. The feasibility of this "lab-in-tube" approach for binary phase diagram determination in a water-surfactant (C12E5) system was demonstrated.

Effect of Yifukang oral liquid on gastric emptying and intestinal peristalsis in mice

NASA Astrophysics Data System (ADS)

Sun, Jianhua; Li, Jun; Li, Xianyu; Hao, Shaojun; Guo, Junyi; Ma, Zhenzhen; Zhang, Zhengchen

2018-04-01

To observe the effect of Yifukang oral liquid on gastric emptying and intestinal peristalsis in mice. Methods: 60 mice were randomly divided into 5 groups. The suspension of Baohe Pill and the same volume of normal saline group were given once a day for 7 days. After the last administration for 30 minutes, 0.25 ml of 0.04% phenolic red solution was administered by stomach. After 20 minutes, the animals were killed, the stomach was removed, the gastric contents were cleaned, and the lotion 5ml was centrifuged. The absorbance of the supernatant was measured by TU-1901 ultraviolet spectrophotometer at the wavelength of 560nm. The residual rate of gastric phenolic red was calculated. Rate was used to evaluate gastric emptying velocity.60 mice were randomly divided into five groups: group 5, large, medium, small Yifukang oral liquid dosage group, pill suspension and the same volume normal saline. After 20 min after the last dose of carbon powder suspension, the mice were sacrificed, the abdominal cavity was cut open, the intestine of the ileocecum was cut off, the intestinal mesentery was separated, the total length of the small intestine (cm) was measured, and the distance (cm) in the small intestine was measured, and the end-of-carbon propulsion rate was calculated. Compared with the blank group, small dose of Yi Fu Kang group and Baohe Pill group could significantly promote the ability of gastric emptying in mice. Compared with the blank group, small dose group and rehabilitation benefits Baohewan group can significantly promote the gastric emptying ability of mice (P<0.01), high dose group had no obvious benefit rehabilitation ability to promote gastric emptying in mice. Yi Fu Kang oral liquid group could significantly increase the percentage of small intestine carbon powder(P<0.01), Large, medium-dose Yifukang oral liquid and Baofuwan group could significantly increase the percentage of small intestinal carbon in mice (P<0.05). Yi Fukang oral liquid has the effect of promoting gastric emptying and small intestinal peristalsis.

A Review and Evaluation of the Phase Equilibria, Liquid-Phase Heats of Mixing and Excess Volumes, and Gas-Phase PVT Measurements for Nitrogen+Methane

NASA Astrophysics Data System (ADS)

Kidnay, A. J.; Miller, R. C.; Sloan, E. D.; Hiza, M. J.

1985-07-01

The available experimental data for vapor-liquid equilibria, heat of mixing, change in volume on mixing for liquid mixtures, and gas-phase PVT measurements for nitrogen+methane have been reviewed and where possible evaluated for consistency. The derived properties chosen for analysis and correlation were liquid mixture excess Gibbs free energies, and Henry's constants.

Optical Mass Gauging System for Measuring Liquid Levels in a Reduced Gravity Environment

NASA Technical Reports Server (NTRS)

Sullenberger, Ryan M.; Munoz, Wesley M.; Lyon, Matt P.; Vogel, Kenny; Yalin, Azer P.; Korman, Valentin; Polzin, Kurt A.

2010-01-01

A compact and rugged fiber-coupled liquid volume sensor designed for flight on a sounding rocket platform is presented. The sensor consists of a Mach-Zehnder interferometer capable of measuring the amount of liquid contained in a tank under any gravitational conditions, including a microgravity environment, by detecting small changes in the index of refraction of the gas contained within a sensing region. By monitoring changes in the interference fringe pattern as the system undergoes a small compression provided by a piston, the ullage volume of a tank can be directly measured allowing for a determination of the liquid volume. To demonstrate the technique, data are acquired using two tanks containing different volumes of liquid, which are representative of the levels of liquid in a tank at different time periods during a mission. The two tanks are independently exposed to the measurement apparatus, allowing for a determination of the liquid level in each. In a controlled, laboratory test of the unit, the system demonstrated a capability of measuring a liquid level in an individual tank of 10.53 mL with a 2% error. The overall random uncertainty for the flight system is higher than that one test, at +/- 1.5 mL.

Synthesis and analysis of foam drainage agent for gas well in Jilin Oilfield

NASA Astrophysics Data System (ADS)

Qiao, Sanyuan; Liu, Qingwang; Fan, Zhenzhong; Wang, Jigang; Xu, Jianjun

2017-05-01

The gas well in Jilin oil field has the characteristics of large temperature variation range and high condensate oil content. So the foam drainage agent of the gas well in Jilin oil field needs to have the performance of oil resistance and less effected by temperature. In this paper, a main foaming agent named lauramidopropyl betaine (LAB) and two kinds of auxiliary foaming agent named sodium alcohol ether sulphate (AES) and lauramidopropylamine oxide (LAO). Through the evaluation of the static foaming capacity and dynamic liquid carrying capacity, the AES is more suitable for LAB. The foaming agent with 70% LAB and 30% AES has 138mm foam height with ROSS-Miles equipment; stirring foam volume can reach 480mL, the half-life of foam is 520s. When the ventilation volume is 8L/min the liquid carrying capacity of 10% of the condensate oil content reached 82g. When the foaming agent concentration is 2%, the liquid carrying capacity of 10% of the condensate oil content reached 75g. When the aeration rate reaches 8-10L/min, the liquid carrying capacity of foam drainage agent can reach the best. The foam drainage agent can retain the performance after 120°C aging for 12h, these performances above can satisfy the requirements for gas well foam drainage in Jilin Oil Field.

Lessons: Science. Slime!

ERIC Educational Resources Information Center

VanCleave, Janice

2000-01-01

Describes a science activity in which students make a non-Newtonian fluid (slime), which has both solid and liquid properties. After reviewing the shape and volume of solids and volume of liquids, students make the slime using glue, liquid starch, and food coloring. They can experiment by rolling and dropping slime balls and by pulling the slime…

Preservation of Liquid Biological Samples

NASA Technical Reports Server (NTRS)

Putcha, Lakshmi (Inventor); Nimmagudda, Ramalingeshwara R. (Inventor)

2000-01-01

The present invention provides a method of preserving a liquid biological sample, comprising the step of: contacting said liquid biological sample with a preservative comprising, sodium benzoate in an amount of at least about 0.15% of the sample (weight/volume) and citric acid in an amount of at least about 0.025% of the sample (weight/volume).

Ionic liquids gels: Soft materials for environmental remediation.

PubMed

Marullo, Salvatore; Rizzo, Carla; Dintcheva, Nadka T; Giannici, Francesco; D'Anna, Francesca

2018-05-01

Nanostructured sorbents and, in particular, supramolecular gels are emerging as efficient materials for the removal of toxic contaminants from water, like industrial dyes. It is also known that ionic liquids can dissolve significant amounts of dyes. Consequently, supramolecular ionic liquids gels could be highly efficient sorbents for dyes removal. This would also contribute to overcome the drawbacks associated with dye removal by liquid-liquid extraction with neat ionic liquids which would require large volumes of extractant and a more difficult separation of the phases. Herein we employed novel supramolecular ionic liquid gels based on diimidazolium salts bearing naturally occurring or biomass derived anions, to adsorb cationic and anionic dyes from wastewaters. We also carried out a detailed investigation of thermal, structural, morphological and rheological features of our gels to identify which of them are key in designing better sorbents for environmental remediation. The most effective gels showed fast and thorough removal of cationic dyes like Rhodamine B. These gels could also be reused up to 20 times without any loss in removal efficiency. Overall, our ionic gels outperform most of gel-based sorbents systems so far reported in literature. Copyright © 2018 Elsevier Inc. All rights reserved.

Development of a multi-matrix LC-MS/MS method for urea quantitation and its application in human respiratory disease studies.

PubMed

Wang, Jianshuang; Gao, Yang; Dorshorst, Drew W; Cai, Fang; Bremer, Meire; Milanowski, Dennis; Staton, Tracy L; Cape, Stephanie S; Dean, Brian; Ding, Xiao

2017-01-30

In human respiratory disease studies, liquid samples such as nasal secretion (NS), lung epithelial lining fluid (ELF), or upper airway mucosal lining fluid (MLF) are frequently collected, but their volumes often remain unknown. The lack of volume information makes it hard to estimate the actual concentration of recovered active pharmaceutical ingredient or biomarkers. Urea has been proposed to serve as a sample volume marker because it can freely diffuse through most body compartments and is less affected by disease states. Here, we report an easy and reliable LC-MS/MS method for cross-matrix measurement of urea in serum, plasma, universal transfer medium (UTM), synthetic absorptive matrix elution buffer 1 (SAMe1) and synthetic absorptive matrix elution buffer 2 (SAMe2) which are commonly sampled in human respiratory disease studies. The method uses two stable-isotope-labeled urea isotopologues, [ 15 N 2 ]-urea and [ 13 C, 15 N 2 ]-urea, as the surrogate analyte and the internal standard, respectively. This approach provides the best measurement consistency across different matrices. The analyte extraction was individually optimized in each matrix. Specifically in UTM, SAMe1 and SAMe2, the unique salting-out assisted liquid-liquid extraction (SALLE) not only dramatically reduces the matrix interferences but also improves the assay recovery. The use of an HILIC column largely increases the analyte retention. The typical run time is 3.6min which allows for high throughput analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

Kirkwood-Buff integrals of finite systems: shape effects

NASA Astrophysics Data System (ADS)

Dawass, Noura; Krüger, Peter; Simon, Jean-Marc; Vlugt, Thijs J. H.

2018-06-01

The Kirkwood-Buff (KB) theory provides an important connection between microscopic density fluctuations in liquids and macroscopic properties. Recently, Krüger et al. derived equations for KB integrals for finite subvolumes embedded in a reservoir. Using molecular simulation of finite systems, KB integrals can be computed either from density fluctuations inside such subvolumes, or from integrals of radial distribution functions (RDFs). Here, based on the second approach, we establish a framework to compute KB integrals for subvolumes with arbitrary convex shapes. This requires a geometric function w(x) which depends on the shape of the subvolume, and the relative position inside the subvolume. We present a numerical method to compute w(x) based on Umbrella Sampling Monte Carlo (MC). We compute KB integrals of a liquid with a model RDF for subvolumes with different shapes. KB integrals approach the thermodynamic limit in the same way: for sufficiently large volumes, KB integrals are a linear function of area over volume, which is independent of the shape of the subvolume.

Preparation of highly infective Leishmania promastigotes by cultivation on SNB-9 biphasic medium.

PubMed

Grekov, Igor; Svobodová, Milena; Nohýnková, Eva; Lipoldová, Marie

2011-12-01

Protozoan hemoflagellates Leishmania are causative agents of leishmaniases and an important biological model for study of host-pathogen interaction. A wide range of methods of Leishmania cultivation on both biphasic and liquid media is available. Biphasic media are considered to be superior for initial isolation of the parasites and obtaining high promastigote infectivity; however, liquid media are more suitable for large-scale experiments. The aim of the present study was the adaptation and optimization of the cultivation of Leishmania promastigotes on a biphasic SNB-9 (saline-neopeptone-blood 9) medium that was originally developed for Trypanosoma cultivation and combines the advantages of biphasic and liquid media. SNB-9 medium is characterized with a large volume of the liquid phase, which facilitates the manipulation with the culture and provides parasite yields comparable to parasite yields on such liquid medium as Schneider's Insect Medium. We demonstrate that SNB-9 very considerably surpasses Schneider's Insect Medium in in vitro infectivity of the parasites. Additionally, we show that the ratio of apoptotic parasites, which are important for the infectivity of the inoculum, in Leishmania culture in SNB-9 is higher than in Leishmania culture in Schneider's Insect Medium. Thus, we demonstrate that the cultivation of Leishmania on SNB-9 reliably yields highly infective promastigotes suitable for experimental infection. Copyright © 2011 Elsevier B.V. All rights reserved.

Methods to control phase inversions and enhance mass transfer in liquid-liquid dispersions

DOEpatents

Tsouris, Constantinos; Dong, Junhang

2002-01-01

The present invention is directed to the effects of applied electric fields on liquid-liquid dispersions. In general, the present invention is directed to the control of phase inversions in liquid-liquid dispersions. Because of polarization and deformation effects, coalescence of aqueous drops is facilitated by the application of electric fields. As a result, with an increase in the applied voltage, the ambivalence region is narrowed and shifted toward higher volume fractions of the dispersed phase. This permits the invention to be used to ensure that the aqueous phase remains continuous, even at a high volume fraction of the organic phase. Additionally, the volume fraction of the organic phase may be increased without causing phase inversion, and may be used to correct a phase inversion which has already occurred. Finally, the invention may be used to enhance mass transfer rates from one phase to another through the use of phase inversions.

The analysis of the wavefront aberration caused by the gravity of the tunable-focus liquid-filled membrane lens

NASA Astrophysics Data System (ADS)

Zhang, Wei; Liu, Pengfei; Wei, Xiaona; Zhuang, Songlin; Yang, Bo

2010-11-01

Liquid lens is a novel optical device which can implement active zooming. With liquid lens, zoom camera can be designed with more miniature size and simpler structure than before. It is thought that the micro zoom system with liquid lens has a very wide potential applications in many fields, in which the volume and weight of the system are critically limited, such as endoscope, mobile, PDA and so on. There are mainly three types of tunable-focus liquid lens: liquid crystal lens, electrowetting effect based liquid lens and liquid-filled membrane lens. Comparing with the other two kinds of liquid lens, the liquid-filled membrane lens has the advantages of simple structure, flexible aperture and high zooming efficiency. But its membrane surface will have an initial shape deformation caused by the gravity when the aperture of the lens is at large size, which will lead to the wave front aberration and the imaging quality impairing. In this paper, the initial deformation of the lens caused by the gravity was simulated based on the theory of Elastic Mechanics, which was calculated by the Finite Element Analysis method. The relationship between the diameter of the lens and the wave front aberration caused by the gravity was studied. And the Optical path difference produced by different liquid density was also analyzed.

Method and apparatus for electrokinetic transport

NASA Technical Reports Server (NTRS)

James, Patrick Ismail (Inventor); Stejic, George (Inventor)

2012-01-01

Controlled electrokinetic transport of constituents of liquid media can be achieved by connecting at least two volumes containing liquid media with at least one dielectric medium with opposing dielectric surfaces in direct contact with said liquid media, and establishing at least one conduit across said dielectric medium, with a conduit inner surface surrounding a conduit volume and at least a first opening and a second opening opposite to the first opening. The conduit is arranged to connect two volumes containing liquid media and includes a set of at least three electrodes positioned in proximity of the inner conduit surface. A power supply is arranged to deliver energy to the electrodes such that time-varying potentials inside the conduit volume are established, where the superposition of said potentials represents at least one controllable traveling potential well that can travel between the opposing conduit openings.

Low energy stage study. Volume 1: Executive summary. [propulsion system configurations for orbital launching of space shuttle payloads

NASA Technical Reports Server (NTRS)

1978-01-01

Cost effective approaches for placing automated payloads into circular and elliptical orbits using energy requirements significantly lower than that provided by the smallest, currently planned shuttle upper stage, SSUS-D, were investigated. Launch costs were derived using both NASA existing/planned launch approaches as well as new propulsion concepts meeting low-energy regime requirements. Candidate new propulsion approaches considered were solid (tandem, cluster, and controlled), solid/liquid combinations and all-liquid stages. Results show that the most economical way to deliver the 129 low energy payloads is basically with a new modular, short liquid bipropellant stage system for the large majority of the payloads. For the remainder of the payloads, use the shuttle with integral OMS and the Scout form for a few specialized payloads until the Shuttle becomes operational.

Pulsed high voltage electric discharge disinfection of microbially contaminated liquids.

PubMed

Anpilov, A M; Barkhudarov, E M; Christofi, N; Kop'ev, V A; Kossyi, I A; Taktakishvili, M I; Zadiraka, Y

2002-01-01

To examine the use of a novel multielectrode slipping surface discharge (SSD) treatment system, capable of pulsed plasma discharge directly in water, in killing micro-organisms. Potable water containing Escherichia coli and somatic coliphages was treated with pulsed electric discharges generated by the SSD. The SSD system was highly efficient in the microbial disinfection of water with a low energy utilization (eta approximately 10-4 kW h l-1). The SSD treatment was effective in the destruction of E. coli and its coliphages through the generation of u.v. radiation, ozone and free radicals. The non-thermal treatment method can be used for the eradication of micro-organisms in a range of contaminated liquids, including milk, negating the use of pasteurization. The method utilizes multipoint electric discharges capable of treating large volumes of liquid under static and flowing regimes.

Three-Dimensional Simulation of Liquid Drop Dynamics Within Unsaturated Vertical Hele-Shaw Cells

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

Hai Huang; Paul Meakin

A three-dimensional, multiphase fluid flow model with volume of fluid-interface tracking was developed and applied to study the multiphase dynamics of moving liquid drops of different sizes within vertical Hele-Shaw cells. The simulated moving velocities are significantly different from those obtained from a first-order analytical approximation, based on simple force-balance concepts. The simulation results also indicate that the moving drops can exhibit a variety of shapes and that the transition among these different shapes is largely determined by the moving velocities. More important, there is a transition from a linear moving regime at small capillary numbers, in which the capillarymore » number scales linearly with the Bond number, to a nonlinear moving regime at large capillary numbers, in which the moving drop releases a train of droplets from its trailing edge. The train of droplets forms a variety of patterns at different moving velocities.« less

Laser-induced incandescence measurements of soot in turbulent pool fires.

PubMed

Frederickson, Kraig; Kearney, Sean P; Grasser, Thomas W

2011-02-01

We present what we believe to be the first application of the laser-induced incandescence (LII) technique to large-scale fire testing. The construction of an LII instrument for fire measurements is presented in detail. Soot volume fraction imaging from 2 m diameter pool fires burning blended toluene/methanol liquid fuels is demonstrated along with a detailed report of measurement uncertainty in the challenging pool fire environment. Our LII instrument relies upon remotely located laser, optical, and detection systems and the insertion of water-cooled, fiber-bundle-coupled collection optics into the fire plume. Calibration of the instrument was performed using an ethylene/air laminar diffusion flame produced by a Santoro-type burner, which allowed for the extraction of absolute soot volume fractions from the LII images. Single-laser-shot two-dimensional images of the soot layer structure are presented with very high volumetric spatial resolution of the order of 10(-5) cm3. Probability density functions of the soot volume fraction fluctuations are constructed from the large LII image ensembles. The results illustrate a highly intermittent soot fluctuation field with potentially large macroscale soot structures and clipped soot probability densities.

Use of nitrogen to remove solvent from through oven transfer adsorption desorption interface during analysis of polycyclic aromatic hydrocarbons by large volume injection in gas chromatography.

PubMed

Áragón, Alvaro; Toledano, Rosa M; Cortés, José M; Vázquez, Ana M; Villén, Jesús

2014-04-25

The through oven transfer adsorption desorption (TOTAD) interface allows large volume injection (LVI) in gas chromatography and the on-line coupling of liquid chromatography and gas chromatography (LC-GC), enabling the LC step to be carried out in normal as well as in reversed phase. However, large amounts of helium, which is both expensive and scarce, are necessary for solvent elimination. We describe how slight modification of the interface and the operating mode allows nitrogen to be used during the solvent elimination steps. In order to evaluate the performance of the new system, volumes ranging from 20 to 100μL of methanolic solutions of four polycyclic aromatic hydrocarbons (PAHs) were sampled. No significant differences were found in the repeatability and sensitivity of the analyses of standard PAH solutions when using nitrogen or helium. The performance using the proposed modification was similar and equally satisfactory when using nitrogen or helium for solvent elimination in the TOTAD interface. In conclusion, the use of nitrogen will make analyses less expensive. Copyright © 2014 Elsevier B.V. All rights reserved.

Silicone rod extraction followed by liquid desorption-large volume injection-programmable temperature vaporiser-gas chromatography-mass spectrometry for trace analysis of priority organic pollutants in environmental water samples.

PubMed

Delgado, Alejandra; Posada-Ureta, Oscar; Olivares, Maitane; Vallejo, Asier; Etxebarria, Nestor

2013-12-15

In this study a priority organic pollutants usually found in environmental water samples were considered to accomplish two extraction and analysis approaches. Among those compounds organochlorine compounds, pesticides, phthalates, phenols and residues of pharmaceutical and personal care products were included. The extraction and analysis steps were based on silicone rod extraction (SR) followed by liquid desorption in combination with large volume injection-programmable temperature vaporiser (LVI-PTV) and gas chromatography-mass spectrometry (GC-MS). Variables affecting the analytical response as a function of the programmable temperature vaporiser (PTV) parameters were firstly optimised following an experimental design approach. The SR extraction and desorption conditions were assessed afterwards, including matrix modification, time extraction, and stripping solvent composition. Subsequently, the possibility of performing membrane enclosed sorptive coating extraction (MESCO) as a modified extraction approach was also evaluated. The optimised method showed low method detection limits (3-35 ng L(-1)), acceptable accuracy (78-114%) and precision values (<13%) for most of the studied analytes regardless of the aqueous matrix. Finally, the developed approach was successfully applied to the determination of target analytes in aqueous environmental matrices including estuarine and wastewater samples. © 2013 Elsevier B.V. All rights reserved.

Zwitterionic, cationic, and anionic fluorinated chemicals in aqueous film forming foam formulations and groundwater from U.S. military bases by nonaqueous large-volume injection HPLC-MS/MS.

PubMed

Backe, Will J; Day, Thomas C; Field, Jennifer A

2013-05-21

A new analytical method was developed to quantify 26 newly-identified and 21 legacy (e.g. perfluoroalkyl carboxylates, perfluoroalkyl sulfonates, and fluorotelomer sulfonates) per and polyfluorinated alkyl substances (PFAS) in groundwater and aqueous film forming foam (AFFF) formulations. Prior to analysis, AFFF formulations were diluted into methanol and PFAS in groundwater were micro liquid-liquid extracted. Methanolic dilutions of AFFF formulations and groundwater extracts were analyzed by large-volume injection (900 μL) high-performance liquid chromatography tandem mass spectrometry. Orthogonal chromatography was performed using cation exchange (silica) and anion exchange (propylamine) guard columns connected in series to a reverse-phase (C18) analytical column. Method detection limits for PFAS in groundwater ranged from 0.71 ng/L to 67 ng/L, and whole-method accuracy ranged from 96% to 106% for analytes for which matched authentic analytical standards were available. For analytes without authentic analytical standards, whole-method accuracy ranged from 78 % to 144 %, and whole-method precision was less than 15 % relative standard deviation for all analytes. A demonstration of the method on groundwater samples from five military bases revealed eight of the 26 newly-identified PFAS present at concentrations up to 6900 ng/L. The newly-identified PFAS represent a minor fraction of the fluorinated chemicals in groundwater relative to legacy PFAS. The profiles of PFAS in groundwater differ from those found in fluorotelomer- and electrofluorination-based AFFF formulations, which potentially indicates environmental transformation of PFAS.

Measurement of gastric meal and secretion volumes using magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Hoad, C. L.; Parker, H.; Hudders, N.; Costigan, C.; Cox, E. F.; Perkins, A. C.; Blackshaw, P. E.; Marciani, L.; Spiller, R. C.; Fox, M. R.; Gowland, P. A.

2015-02-01

MRI can assess multiple gastric functions without ionizing radiation. However, time consuming image acquisition and analysis of gastric volume data, plus confounding of gastric emptying measurements by gastric secretions mixed with the test meal have limited its use to research centres. This study presents an MRI acquisition protocol and analysis algorithm suitable for the clinical measurement of gastric volume and secretion volume. Reproducibility of gastric volume measurements was assessed using data from 10 healthy volunteers following a liquid test meal with rapid MRI acquisition within one breath-hold and semi-automated analysis. Dilution of the ingested meal with gastric secretion was estimated using a respiratory-triggered T1 mapping protocol. Accuracy of the secretion volume measurements was assessed using data from 24 healthy volunteers following a mixed (liquid/solid) test meal with MRI meal volumes compared to data acquired using gamma scintigraphy (GS) on the same subjects studied on a separate study day. The mean ± SD coefficient of variance between 3 observers for both total gastric contents (including meal, secretions and air) and just the gastric contents (meal and secretion only) was 3  ±  2% at large gastric volumes (>200 ml). Mean ± SD secretion volumes post meal ingestion were 64  ±  51 ml and 110  ±  40 ml at 15 and 75 min, respectively. Comparison with GS meal volumes, showed that MRI meal only volume (after correction for secretion volume) were similar to GS, with a linear regression gradient ± std err of 1.06  ±  0.10 and intercept -11  ±  24 ml. In conclusion, (i) rapid volume acquisition and respiratory triggered T1 mapping removed the requirement to image during prolonged breath-holds (ii) semi-automatic analysis greatly reduced the time required to derive measurements and (iii) correction for secretion volumes provided accurate assessment of gastric meal volumes and emptying. Together these features provide the scientific basis of a protocol which would be suitable in clinical practice.

A prototype of volume-controlled tidal liquid ventilator using independent piston pumps.

PubMed

Robert, Raymond; Micheau, Philippe; Cyr, Stéphane; Lesur, Olivier; Praud, Jean-Paul; Walti, Hervé

2006-01-01

Liquid ventilation using perfluorochemicals (PFC) offers clear theoretical advantages over gas ventilation, such as decreased lung damage, recruitment of collapsed lung regions, and lavage of inflammatory debris. We present a total liquid ventilator designed to ventilate patients with completely filled lungs with a tidal volume of PFC liquid. The two independent piston pumps are volume controlled and pressure limited. Measurable pumping errors are corrected by a programmed supervisor module, which modifies the inserted or withdrawn volume. Pump independence also allows easy functional residual capacity modifications during ventilation. The bubble gas exchanger is divided into two sections such that the PFC exiting the lungs is not in contact with the PFC entering the lungs. The heating system is incorporated into the metallic base of the gas exchanger, and a heat-sink-type condenser is placed on top of the exchanger to retrieve PFC vapors. The prototype was tested on 5 healthy term newborn lambs (<5 days old). The results demonstrate the efficiency and safety of the prototype in maintaining adequate gas exchange, normal acido-basis equilibrium, and cardiovascular stability during a short, 2-hour total liquid ventilator. Airway pressure, lung volume, and ventilation scheme were maintained in the targeted range.

Unveiling the relationships among the viscosity equations of glass liquids and colloidal suspensions for obtaining universal equations with the generic free volume concept.

PubMed

Hao, Tian

2015-09-14

The underlying relationships among viscosity equations of glass liquids and colloidal suspensions are explored with the aid of free volume concept. Viscosity equations of glass liquids available in literature are focused and found to have a same physical basis but different mathematical expressions for the free volume. The glass transitions induced by temperatures in glass liquids and the percolation transition induced by particle volume fractions in colloidal suspensions essentially are a second order phase transition: both those two transitions could induce the free volume changes, which in turn determines how the viscosities are going to change with temperatures and/or particle volume fractions. Unified correlations of the free volume to both temperatures and particle volume fractions are thus proposed. The resulted viscosity equations are reducible to many popular viscosity equations currently widely used in literature; those equations should be able to cover many different types of materials over a wide temperature range. For demonstration purpose, one of the simplified versions of those newly developed equations is compared with popular viscosity equations and the experimental data: it can well fit the experimental data over a wide temperature range. The current work reveals common physical grounds among various viscosity equations, deepening our understanding on viscosity and unifying the free volume theory across many different systems.

Acoustically-Enhanced Direct Contact Vapor Bubble Condensation

NASA Astrophysics Data System (ADS)

Boziuk, Thomas; Smith, Marc; Glezer, Ari

2017-11-01

Rate-limited, direct contact vapor condensation of vapor bubbles that are formed by direct steam injection through a nozzle in a quiescent subcooled liquid bath is accelerated using ultrasonic (MHz-range) actuation. A submerged, low power actuator produces an acoustic beam whose radiation pressure deforms the liquid-vapor interface, leading to the formation of a liquid spear that penetrates the vapor bubble to form a vapor torus with a significantly larger surface area and condensation rate. Ultrasonic focusing along the spear leads to the ejection of small, subcooled droplets through the vapor volume that impact the vapor-liquid interface and further enhance the condensation. High-speed Schlieren imaging of the formation and collapse of the vapor bubbles in the absence and presence of actuation shows that the impulse associated with the collapse of the toroidal volume leads to the formation of a turbulent vortex ring in the liquid phase. Liquid motions near the condensing vapor volume are investigated in the absence and presence of acoustic actuation using high-magnification PIV and show the evolution of a liquid jet through the center of the condensing toroidal volume and the formation and advection of vortex ring structures whose impulse appear to increase with temperature difference between the liquid and vapor phases. High-speed image processing is used to assess the effect of the actuation on the temporal and spatial variations in the characteristic scales and condensation rates of the vapor bubbles.

Liquid crystal film development for plasma mirrors and waveplates

NASA Astrophysics Data System (ADS)

Cochran, G. E.; Poole, P. L.; Willis, C.; Hanna, R. J.; Pytel, K.; Sullivan, K. S.; Andereck, C. D.; Schumacher, D. W.

2015-11-01

Many laser-plasma phenomena currently under study depend critically on the quality of the pulse contrast. Costly sacrificial plasma mirrors are now commonly used to improve the temporal laser contrast before target interaction, especially for ion acceleration where high contrast is necessary to achieve interesting new mechanisms. Liquid crystal films were originally developed as variable thickness thin-film targets, and were demonstrated for this purpose in. Varying film formation parameters such as volume, temperature, and draw speed allows thickness control between 10 nm and several 10s of microns, in-situ and under vacuum. Development since that initial work has allowed large area films to be formed, several cm2 in extent, with the same thickness range. The molecular flatness of a freely suspended film renders these films excellent low-cost plasma mirrors, given appropriate formation control. Additionally, the birefringence of the liquid crystal used here permits these films to be used as large area zero-order waveplates at the appropriate thickness. Details on the current state of liquid crystal film application development, including a >1 Hz small area film formation device, will be presented. This work was performed with support from the DARPA PULSE program through a grant from AMRDEC and by the NNSA under contract DE-NA0001976.

High-Field Liquid-State Dynamic Nuclear Polarization in Microliter Samples.

PubMed

Yoon, Dongyoung; Dimitriadis, Alexandros I; Soundararajan, Murari; Caspers, Christian; Genoud, Jeremy; Alberti, Stefano; de Rijk, Emile; Ansermet, Jean-Philippe

2018-05-01

Nuclear hyperpolarization in the liquid state by dynamic nuclear polarization (DNP) has been of great interest because of its potential use in NMR spectroscopy of small samples of biological and chemical compounds in aqueous media. Liquid state DNP generally requires microwave resonators in order to generate an alternating magnetic field strong enough to saturate electron spins in the solution. As a consequence, the sample size is limited to dimensions of the order of the wavelength, and this restricts the sample volume to less than 100 nL for DNP at 9 T (∼260 GHz). We show here a new approach that overcomes this sample size limitation. Large saturation of electron spins was obtained with a high-power (∼150 W) gyrotron without microwave resonators. Since high power microwaves can cause serious dielectric heating in polar solutions, we designed a planar probe which effectively alleviates dielectric heating. A thin liquid sample of 100 μm of thickness is placed on a block of high thermal conductivity aluminum nitride, with a gold coating that serves both as a ground plane and as a heat sink. A meander or a coil were used for NMR. We performed 1 H DNP at 9.2 T (∼260 GHz) and at room temperature with 10 μL of water, a volume that is more than 100× larger than reported so far. The 1 H NMR signal is enhanced by a factor of about -10 with 70 W of microwave power. We also demonstrated the liquid state of 31 P DNP in fluorobenzene containing triphenylphosphine and obtained an enhancement of ∼200.

Research on Volume Measurement System of Weights with Hydrostatic Technique

NASA Astrophysics Data System (ADS)

Wang, Jian; Ren, Xiaoping; Yao, Hong; Cai, Changqing; Zhang, Yue; Zhong, Ruilin; Ding, Jing'an

According to Annex B.7.4 of OIML R111-1, equipment for measuring volume of weights mass ranging from 1 kg to 20 kg including three methods of hydrostatic comparison is described. The equipment consists of a robot arm for transferring weights, a liquid bath, a mass comparator with 26.1 kg of maximum capacity and 1 mg of readability, glass housing, two weight exchangers including in air and in liquid, two weight holders including in air and in liquid, and a controller. The equipment will enable to perform automatically volume measurements.

Evolution of short range order in Ar: Liquid to glass and solid transitions-A computational study

NASA Astrophysics Data System (ADS)

Shor, Stanislav; Yahel, Eyal; Makov, Guy

2018-04-01

The evolution of the short range order (SRO) as a function of temperature in a Lennard-Jones model liquid with Ar parameters was determined and juxtaposed with thermodynamic and kinetic properties obtained as the liquid was cooled (heated) and transformed between crystalline solid or glassy states and an undercooled liquid. The Lennard-Jones system was studied by non-equilibrium molecular dynamics simulations of large supercells (approximately 20000 atoms) rapidly cooled or heated at selected quenching rates and at constant pressure. The liquid to solid transition was identified by discontinuities in the atomic volume and molar enthalpy; the glass transition temperature range was identified from the temperature dependence of the self-diffusion. The SRO was studied within the quasi-crystalline model (QCM) framework and compared with the Steinhardt bond order parameters. Within the QCM it was found that the SRO evolves from a bcc-like order in the liquid through a bct-like short range order (c/a=1.2) in the supercooled liquid which persists into the glass and finally to a fcc-like ordering in the crystalline solid. The variation of the SRO that results from the QCM compares well with that obtained with Steinhardt's bond order parameters. The hypothesis of icosahedral order in liquids and glasses is not supported by our results.

Acoustic levitator for contactless motion and merging of large droplets in air

NASA Astrophysics Data System (ADS)

Bjelobrk, Nada; Nabavi, Majid; Poulikakos, Dimos

2012-09-01

Large droplet transport in a line-focussed acoustic manipulator in terms of maximum droplet size is achieved by employing a driving voltage control mechanism. The maximum volume of the transported droplets in the order of few microliters is thereby increased by three orders of magnitude compared to the constant voltage case, widening the application field of this method significantly. A drop-on-demand droplet generator is used to supply the liquid droplets into the system. The ejected sequence of picoliter-size droplets is guided along trajectories by the acoustic field and accumulates at the selected pressure node, merging into a single large droplet. Droplet movement is achieved by varying the reflector height. This also changes the intensity of the radiation pressure during droplet movement, which in turn could atomise the droplet. The acoustic force is adjusted by regulating the driving voltage of the actuator to keep the liquid droplet suspended in air and to prevent atomisation. In the herein presented levitation concept, liquids with a wide range of surface tension (water and tetradecane were tested) can be transported over distances of several mm. The aspect ratio of the droplet in the acoustic field is shown to be a good indicator for radiation pressure intensity and is kept between 1.1 and 1.4 during droplet transport. Despite certain limitations with volatile liquids, the presented acoustic levitator concept has the potential to expand the range of analytical characterisation and manipulation methods in applications ranging from chemistry and biology.

On the Extraction of Aromatic Compounds from Hydrocarbons by Imidazolium Ionic Liquids

PubMed Central

Cassol, Cláudia C.; Umpierre, Alexandre P.; Ebeling, Günter; Ferrera, Bauer; Chiaro, Sandra S. X.; Dupont, Jairton

2007-01-01

The liquid-liquid equilibrium for the ternary system formed by n-octane and aromatic (alkylbenzenes) and heteroaromatic compounds (nitrogen and sulfur containing heterocyles) and 1-alkyl-3-methylimidazolium ionic liquids (ILs) associated with various anions has been investigated. The selectivity on the extraction of a specific aromatic compound is influenced by anion volume, hydrogen bond strength between the anion and the imidazolium cation and the length of the 1-methyl-3-alkylimidazolium alkyl side chain. The interaction of alkylbenzenes and sulfur heterocyles with the IL is preferentially through CH-π hydrogen bonds and the quantity of these aromatics in the IL phase decreases with the increase of the steric hindrance imposed by the substituents on the aromatic nucleus. In the case of nitrogen heterocycles the interaction occurs preferentially through N(heteroaromatic)-H(imidazolium) hydrogen bonds and the extraction process is largely controlled by the nitrogen heterocycle pKa. Competitive extraction experiments suggest that benzene, pyridine and dibenzothiophene do not compete for the same hydrogen bond sites of the IL.

Oxidation-Mediated Fingering in Liquid Metals

NASA Astrophysics Data System (ADS)

Eaker, Collin B.; Hight, David C.; O'Regan, John D.; Dickey, Michael D.; Daniels, Karen E.

2017-10-01

We identify and characterize a new class of fingering instabilities in liquid metals; these instabilities are unexpected due to the large interfacial tension of metals. Electrochemical oxidation lowers the effective interfacial tension of a gallium-based liquid metal alloy to values approaching zero, thereby inducing drastic shape changes, including the formation of fractals. The measured fractal dimension (D =1.3 ±0.05 ) places the instability in a different universality class than other fingering instabilities. By characterizing changes in morphology and dynamics as a function of droplet volume and applied electric potential, we identify the three main forces involved in this process: interfacial tension, gravity, and oxidative stress. Importantly, we find that electrochemical oxidation can generate compressive interfacial forces that oppose the tensile forces at a liquid interface. The surface oxide layer ultimately provides a physical and electrochemical barrier that halts the instabilities at larger positive potentials. Controlling the competition between interfacial tension and oxidative (compressive) stresses at the interface is important for the development of reconfigurable electronic, electromagnetic, and optical devices that take advantage of the metallic properties of liquid metals.

Numerical modelling of ultrasonic waves in a bubbly Newtonian liquid using a high-order acoustic cavitation model.

PubMed

Lebon, G S Bruno; Tzanakis, I; Djambazov, G; Pericleous, K; Eskin, D G

2017-07-01

To address difficulties in treating large volumes of liquid metal with ultrasound, a fundamental study of acoustic cavitation in liquid aluminium, expressed in an experimentally validated numerical model, is presented in this paper. To improve the understanding of the cavitation process, a non-linear acoustic model is validated against reference water pressure measurements from acoustic waves produced by an immersed horn. A high-order method is used to discretize the wave equation in both space and time. These discretized equations are coupled to the Rayleigh-Plesset equation using two different time scales to couple the bubble and flow scales, resulting in a stable, fast, and reasonably accurate method for the prediction of acoustic pressures in cavitating liquids. This method is then applied to the context of treatment of liquid aluminium, where it predicts that the most intense cavitation activity is localised below the vibrating horn and estimates the acoustic decay below the sonotrode with reasonable qualitative agreement with experimental data. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Sub-μL measurements of the thermal conductivity and heat capacity of liquids.

PubMed

López-Bueno, C; Bugallo, D; Leborán, V; Rivadulla, F

2018-03-07

We present the analysis of the thermal conductivity, κ, and heat capacity, C p , of a wide variety of liquids, covering organic molecular solvents, ionic liquids and water-polymer mixtures. These data were obtained from ≈0.6 μL samples, using an experimental development based on the 3ω method, capable of the simultaneous measurement of κ and C p . In spite of the different type and strength of interactions, expected in a priori so different systems, the ratio of κ to the sound velocity is approximately constant for all of them. This is the consequence of a similar atomic density for all these liquids, notwithstanding their different molecular structures. This was corroborated experimentally by the observation of a C p /V ≈ 1.89 × 10 6 J K -1 m -3 (≈3R/2 per atom), for all liquids studied in this work. Finally, the very small volume of the sample required in this experimental method is an important advantage for the characterization of systems like nanofluids, in which having a large amount of the dispersed phase is sometimes extremely challenging.

Radwaste desk reference - Volume 3, Part 2: Liquid waste management. Final report

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

Deltete, D.; Fisher, S.; Kelly, J.J.

1994-05-01

EPRI began, in late in 1987, to produce a Radwaste Desk Reference that would allow each of the member utilities access to the available information and expertise on radwaste management. EPRI considers this important because radwaste management involves a wide variety of scientific and engineering disciplines. These include chemical and mechanical engineering, chemistry, and health physics. Radwaste management also plays a role in implementing a wide variety of regulatory requirements. These include plant-specific technical specifications, NRC standards for protection against radiation, DOT transportation regulations and major environmental legislation such as the Resource Conservation and Recovery Act. EPRI chose a questionmore » and answer format because it could be easily accessed by radwaste professionals with a variety of interests. The questions were generated at two meetings of utility radwaste professionals and EPRI contractors. Volume 1, which is already in publication, addresses dry active waste generation, processing and measurement. Volume 2 addresses low level waste storage, transportation and disposal. This volume, Volume 3, is being issued in two parts. Part 1 concentrates on the processing of liquid radioactive waste, whereas Part 2, included here, addresses liquid waste management. It includes extensive information and operating practices related to liquid waste generation and control, liquid waste processing systems at existing U.S. nuclear plants, processes for managing wet wastes (handling, dewatering, solidifying, processing, and packaging), and liquid waste measurement and analysis.« less

Fluid intake patterns: an epidemiological study among children and adolescents in Brazil

PubMed Central

2012-01-01

Background Energy from liquids is one of the most important factors that could impact on the high prevalence of children and adolescents obesity around the world. There are few data on the liquid consumption in Brazil. The aim of this study is to evaluate the volume and quality of liquids consumed by Brazilian children and adolescents and to determine the proportion of their daily energy intake composed of liquids. Methods A multicenter study was conducted in five Brazilian cities; the study included 831 participants between 3 and 17 years of age. A four-day dietary record specific to fluids was completed for each individual, and the volume of and Kcal from liquid intake were evaluated. The average number of Kcal in each beverage was determined based on label information, and the daily energy intake data from liquids were compared with the recommendations of the National Health Surveillance Agency (Agência Nacional de Vigilância Sanitária– ANVISA), the Brazilian food regulation authority, according to each subject’s age. Results As the children aged, the volume of carbonated beverages that they consumed increased significantly, and their milk intake decreased significantly. For children between the ages of 3 and 10, milk and dairy products contributed the greatest daily number of Kcal from liquids. Sugar sweetened beverages which included carbonated beverages, nectars and artificial beverages, accounted for 37% and 45% of the total Kcal from liquid intake in the 3- to 6-year-old and 7- to 10- year-old groups, respectively. Among adolescents (participants 11- to 17- years old), most of the energy intake from liquids came from carbonated beverages, which accounted for an average of 207 kcal/day in this group (42% of their total energy intake from liquids). Health professionals should be attentive to the excessive consumption of sugar sweetened beverages in children and adolescents. The movement toward healthier dietary patterns at the individual and population levels may help to improve programs for preventing overweight and obesity in children and adolescents. Conclusion From childhood to adolescence the daily volume of liquid ingested increased reaching a total of 2.0 liters on average. Of this volume, the daily volume of milk ingested decreased while the carbonated drinks, sweetened, nectars and artificial beverages increased significantly. The proportion of water remained constant in about 1/3 of the total volume. From 3 to 17 years of age the energy intake from carbonated beverages increased by about 20%. The carbonated drinks on average corresponded to a tenth of the daily requirements of energy of adolescents. PMID:23167254

Influence of volume ratio of liquid to solid and low pouring temperature on interface structure of cast Babbitt-steel bimetal composite

NASA Astrophysics Data System (ADS)

Fathy, Naglaa; Ramadan, Mohamed

2018-05-01

The influence of volume ratio of liquid to Solid and low pouring temperature on interface structure of cast Babbitt-steel bimetal composite was evaluated for static casting technique. At low pouring temperature of 380 °C, Babbitt microstructures are improved to be finer and more globular. On the other side pouring the Babbitt at low pouring temperature of 380 °C increases the chance of present higher unbonded area percent. Increasing the volume ratio of liquid to solid decreases the Sn-Pb interface thicknesses and increases the bonded interface area. In order to optimize the production of Babbitt-steel bimetal composite at low pouring temperature, the volume ratio of liquid Babbitt to solid steel shell should be higher value that could be more than 5 depending on the extrapolation of current data presented.

A molecular dynamics study of lithium-containing aprotic heterocyclic ionic liquid electrolytes

NASA Astrophysics Data System (ADS)

Lourenço, Tuanan C.; Zhang, Yong; Costa, Luciano T.; Maginn, Edward J.

2018-05-01

Classical molecular dynamics simulations were performed on twelve different ionic liquids containing aprotic heterocyclic anions doped with Li+. These ionic liquids have been shown to be promising electrolytes for lithium ion batteries. Self-diffusivities, lithium transference numbers, densities, and free volumes were computed as a function of lithium concentration. The dynamics and free volume decreased with increasing lithium concentration, and the trends were rationalized by examining the changes to the liquid structure. Of those examined in the present work, it was found that (methyloxymethyl)triethylphosphonium triazolide ionic liquids have the overall best performance.

Chemical bonding between antimony and ionic liquid-derived nitrogen-doped carbon for sodium-ion battery anode

NASA Astrophysics Data System (ADS)

Xu, Xin; Si, Ling; Zhou, Xiaosi; Tu, Fengzhang; Zhu, Xiaoshu; Bao, Jianchun

2017-05-01

Antimony has received a great deal of attention as a promising anode material for sodium-ion batteries (SIBs) due to its high theoretical capacity of 660 mAh g-1. However, this application is significantly hampered by inherent large volume change and sluggish kinetics. To address these issues, an antimony-cyano-based ionic liquid-derived nitrogen-doped carbon (Sbsbnd CNC) hybrid is proposed and synthesized by ball-milling and subsequent pyrolysis treatment. As an anode material for SIBs, the as-synthesized Sbsbnd CNC hybrid delivers reversible capacities of 475 mAh g-1 at a current density of 100 mA g-1 and 203 mAh g-1 at 5000 mA g-1, and a 92.4% capacity retention based on the first-cycle capacity after 150 cycles at 100 mA g-1. Using ex situ X-ray photoelectron spectroscopy and elemental mapping techniques, we attribute the good structural integrity to the formation of Sbsbnd Nsbnd C bonds between Sb and the cyano-based ionic liquid-derived N-doped carbon matrix. Moreover, the presence of N-doped carbon network in the hybrid material serves as a robust protective cover and an electrical highway, buffering the substantial volume expansion of Sb nanoparticles and ensuring the fast electron transport for stable cycling operation.

Nanoliter-Scale Protein Crystallization and Screening with a Microfluidic Droplet Robot

PubMed Central

Zhu, Ying; Zhu, Li-Na; Guo, Rui; Cui, Heng-Jun; Ye, Sheng; Fang, Qun

2014-01-01

Large-scale screening of hundreds or even thousands of crystallization conditions while with low sample consumption is in urgent need, in current structural biology research. Here we describe a fully-automated droplet robot for nanoliter-scale crystallization screening that combines the advantages of both automated robotics technique for protein crystallization screening and the droplet-based microfluidic technique. A semi-contact dispensing method was developed to achieve flexible, programmable and reliable liquid-handling operations for nanoliter-scale protein crystallization experiments. We applied the droplet robot in large-scale screening of crystallization conditions of five soluble proteins and one membrane protein with 35–96 different crystallization conditions, study of volume effects on protein crystallization, and determination of phase diagrams of two proteins. The volume for each droplet reactor is only ca. 4–8 nL. The protein consumption significantly reduces 50–500 fold compared with current crystallization stations. PMID:24854085

Nanoliter-scale protein crystallization and screening with a microfluidic droplet robot.

PubMed

Zhu, Ying; Zhu, Li-Na; Guo, Rui; Cui, Heng-Jun; Ye, Sheng; Fang, Qun

2014-05-23

Large-scale screening of hundreds or even thousands of crystallization conditions while with low sample consumption is in urgent need, in current structural biology research. Here we describe a fully-automated droplet robot for nanoliter-scale crystallization screening that combines the advantages of both automated robotics technique for protein crystallization screening and the droplet-based microfluidic technique. A semi-contact dispensing method was developed to achieve flexible, programmable and reliable liquid-handling operations for nanoliter-scale protein crystallization experiments. We applied the droplet robot in large-scale screening of crystallization conditions of five soluble proteins and one membrane protein with 35-96 different crystallization conditions, study of volume effects on protein crystallization, and determination of phase diagrams of two proteins. The volume for each droplet reactor is only ca. 4-8 nL. The protein consumption significantly reduces 50-500 fold compared with current crystallization stations.

Alveolar edema dispersion and alveolar protein permeability during high volume ventilation: effect of positive end-expiratory pressure.

PubMed

de Prost, Nicolas; Roux, Damien; Dreyfuss, Didier; Ricard, Jean-Damien; Le Guludec, Dominique; Saumon, Georges

2007-04-01

To evaluate whether PEEP affects intrapulmonary alveolar edema liquid movement and alveolar permeability to proteins during high volume ventilation. Experimental study in an animal research laboratory. 46 male Wistar rats. A (99m)Tc-labeled albumin solution was instilled in a distal airway to produce a zone of alveolar flooding. Conventional ventilation (CV) was applied for 30 min followed by various ventilation strategies for 3 h: CV, spontaneous breathing, and high volume ventilation with different PEEP levels (0, 6, and 8 cmH(2)O) and different tidal volumes. Dispersion of the instilled liquid and systemic leakage of (99m)Tc-albumin from the lungs were studied by scintigraphy. The instillation protocol produced a zone of alveolar flooding that stayed localized during CV or spontaneous breathing. High volume ventilation dispersed alveolar liquid in the lungs. This dispersion was prevented by PEEP even when tidal volume was the same and thus end-inspiratory pressure higher. High volume ventilation resulted in the leakage of instilled (99m)Tc-albumin from the lungs. This increase in alveolar albumin permeability was reduced by PEEP. Albumin permeability was more affected by the amplitude of tidal excursions than by overall lung distension. PEEP prevents the dispersion of alveolar edema liquid in the lungs and lessens the increase in alveolar albumin permeability due to high volume ventilation.

Flowmeter for determining average rate of flow of liquid in a conduit

DOEpatents

Kennerly, J.M.; Lindner, G.M.; Rowe, J.C.

1981-04-30

This invention is a compact, precise, and relatively simple device for use in determining the average rate of flow of a liquid through a conduit. The liquid may be turbulent and contain bubbles of gas. In a preferred embodiment, the flowmeter includes an electrical circuit and a flow vessel which is connected as a segment of the conduit conveying the liquid. The vessel is provided with a valved outlet and is partitioned by a vertical baffle into coaxial chambers whose upper regions are vented to permit the escape of gas. The inner chamber receives turbulent downflowing liquid from the conduit and is sized to operate at a lower pressure than the conduit, thus promoting evolution of gas from the liquid. Lower zones of the two chambers are interconnected so that the downflowing liquid establishes liquid levels in both chambers. The liquid level in the outer chamber is comparatively calm, being to a large extent isolated from the turbulence in the inner chamber once the liquid in the outer chamber has risen above the liquid-introduction zone for that chamber. Lower and upper probes are provided in the outer chamber for sensing the liquid level therein at points above its liquid-introduction zone. An electrical circuit is connected to the probes to display the time required for the liquid level in the outer chamber to successively contact the lower and upper probes. The average rate of flow through the conduit can be determined from the above-mentioned time and the vessel volume filled by the liquid during that time.

Flowmeter for determining average rate of flow of liquid in a conduit

DOEpatents

Kennerly, John M.; Lindner, Gordon M.; Rowe, John C.

1982-01-01

This invention is a compact, precise, and relatively simple device for use in determining the average rate of flow of a liquid through a conduit. The liquid may be turbulent and contain bubbles of gas. In a preferred embodiment, the flowmeter includes an electrical circuit and a flow vessel which is connected as a segment of the conduit conveying the liquid. The vessel is provided with a valved outlet and is partitioned by a vertical baffle into coaxial chambers whose upper regions are vented to permit the escape of gas. The inner chamber receives turbulent downflowing liquid from the conduit and is sized to operate at a lower pressure than the conduit, thus promoting evolution of gas from the liquid. Lower zones of the two chambers are interconnected so that the downflowing liquid establishes liquid levels in both chambers. The liquid level in the outer chamber is comparatively calm, being to a large extent isolated from the turbulence in the inner chamber once the liquid in the outer chamber has risen above the liquid-introduction zone for that chamber. Lower and upper probes are provided in the outer chamber for sensing the liquid level therein at points above its liquid-introduction zone. An electrical circuit is connected to the probes to display the time required for the liquid level in the outer chamber to successively contact the lower and upper probes. The average rate of flow through the conduit can be determined from the above-mentioned time and the vessel volume filled by the liquid during that time.

Toward New Horizons. Volume 7. Aircraft Fuels and Propellants

DTIC Science & Technology

1946-05-01

energy in the exhaust gas. At the high -power rich condition, a relatively large amount of chemical heat is discarded in the form of unburned carbon...mental studies on the preparation, properties, and methods of use of low-weight high - energy -producing materials, such as metallic hydrides, atomic and...LIMITED POWER The foregoing discussion has been predicated upon the need for a plentiful liquid fuel of high energy content and more particularly upon

Surface tension confined liquid cryogen cooler

NASA Technical Reports Server (NTRS)

Castles, Stephen H. (Inventor); Schein, Michael E. (Inventor)

1989-01-01

A cryogenic cooler is provided for use in craft such as launch, orbital, and space vehicles subject to substantial vibration, changes in orientation, and weightlessness. The cooler contains a small pore, large free volume, low density material to restrain a cryogen through surface tension effects during launch and zero-g operations and maintains instrumentation within the temperature range of 10 to 140 K. The cooler operation is completely passive, with no inherent vibration or power requirements.

High-performance single nanowire tunnel diodes.

PubMed

Wallentin, Jesper; Persson, Johan M; Wagner, Jakob B; Samuelson, Lars; Deppert, Knut; Borgström, Magnus T

2010-03-10

We demonstrate single nanowire tunnel diodes with room temperature peak current densities of up to 329 A/cm(2). Despite the large surface to volume ratio of the type-II InP-GaAs axial heterostructure nanowires, we measure peak to valley current ratios (PVCR) of up to 8.2 at room temperature and 27.6 at liquid helium temperature. These sub-100-nm-diameter structures are promising components for solar cells as well as electronic applications.

77 FR 28411 - Self-Regulatory Organizations; NYSE Arca, Inc.; Notice of Filing and Immediate Effectiveness of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-14

... liquidity from the Book to pay a reduced fee of $0.0029 per share if they directly execute providing volume... liquidity from the Book to pay a reduced fee of $0.0029 per share if they directly execute providing volume... B Step Up Tier allows ETP Holders and Market Makers that take liquidity from the Book to pay a...

38th JANNAF Combustion Subcommittee Meeting. Volume 1

NASA Technical Reports Server (NTRS)

Fry, Ronald S. (Editor); Eggleston, Debra S. (Editor); Gannaway, Mary T. (Editor)

2002-01-01

This volume, the first of two volumes, is a collection of 55 unclassified/unlimited-distribution papers which were presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 38th Combustion Subcommittee (CS), 26 th Airbreathing Propulsion Subcommittee (APS), 20th Propulsion Systems Hazards Subcommittee (PSHS), and 21 Modeling and Simulation Subcommittee. The meeting was held 8-12 April 2002 at the Bayside Inn at The Sandestin Golf & Beach Resort and Eglin Air Force Base, Destin, Florida. Topics cover five major technology areas including: 1) Combustion - Propellant Combustion, Ingredient Kinetics, Metal Combustion, Decomposition Processes and Material Characterization, Rocket Motor Combustion, and Liquid & Hybrid Combustion; 2) Liquid Rocket Engines - Low Cost Hydrocarbon Liquid Rocket Engines, Liquid Propulsion Turbines, Liquid Propulsion Pumps, and Staged Combustion Injector Technology; 3) Modeling & Simulation - Development of Multi- Disciplinary RBCC Modeling, Gun Modeling, and Computational Modeling for Liquid Propellant Combustion; 4) Guns Gun Propelling Charge Design, and ETC Gun Propulsion; and 5) Airbreathing - Scramjet an Ramjet- S&T Program Overviews.

Photoswitchable gas permeation membranes based on azobenzene-doped liquid crystals II. Permeation-switching characterization under variable volume and variable pressure conditions

NASA Astrophysics Data System (ADS)

Glowacki, E.; Hunt, K.; Abud, D.; Marshall, K. L.

2010-08-01

Stimuli-responsive gas permeation membranes hold substantial potential for industrial processes as well as in analytical and screening applications. Such "smart" membrane systems, although prevalent in liquid mass-transfer manipulations, have yet to be realized for gas applications. We report our progress in developing gas permeation membranes in which liquid crystalline (LC) phases afford the active region of permeation. To achieve rapid and reversible switching between LC and isotropic permeation states, we harnessed the photomechanical action of mesogenic azobenzene dyes that can produce isothermal nematic-isotropic transitions. Both polymeric and low-molecular-weight LC materials were tested. Three different dye-doped LC mixtures with mesogenic azo dyes were infused into commercially available track-etched porous membranes with regular cylindrical pores (0.4 to 10.0 μm). Photoinduced isothermal phase changes in the imbibed material produced large and fully reversible changes in the permeability of the membrane to nitrogen with 5 s of irradiation at 2 mW/cm2. Using two measurement tools constructed in-house, the permeability of the photoswitched membranes was determined by both variable-pressure and variable-volume methods. Both the LC and photogenerated isotropic states demonstrate a linear permeability/pressure (ideal sorption) relationship, with up to a 16-fold difference in their permeability coefficients. Liquid crystal compositions can be chosen such that the LC phase is more permeable than the isotropic-or vice versa. This approach is the first system offering reversible tunable gas permeation membranes.

Phage-based biomolecular filter for the capture of bacterial pathogens in liquid streams

NASA Astrophysics Data System (ADS)

Du, Songtao; Chen, I.-Hsuan; Horikawa, Shin; Lu, Xu; Liu, Yuzhe; Wikle, Howard C.; Suh, Sang Jin; Chin, Bryan A.

2017-05-01

This paper investigates a phage-based biomolecular filter that enables the evaluation of large volumes of liquids for the presence of small quantities of bacterial pathogens. The filter is a planar arrangement of phage-coated, strip-shaped magnetoelastic (ME) biosensors (4 mm × 0.8 mm × 0.03 mm), magnetically coupled to a filter frame structure, through which a liquid of interest flows. This "phage filter" is designed to capture specific bacterial pathogens and allow non-specific debris to pass, eliminating the common clogging issue in conventional bead filters. ANSYS Maxwell was used to simulate the magnetic field pattern required to hold ME biosensors densely and to optimize the frame design. Based on the simulation results, a phage filter structure was constructed, and a proof-in-concept experiment was conducted where a Salmonella solution of known concentration were passed through the filter, and the number of captured Salmonella was quantified by plate counting.

Double-diffusive boundary layers along vertical free surfaces

NASA Astrophysics Data System (ADS)

Napolitano, L. G.; Viviani, A.; Savino, R.

1992-05-01

This paper deals with double-diffusive (or thermosolutal) combined free convection, i.e., free convection due to buoyant forces (natural convection) and surface tension gradients (Marangoni convection), which are generated by volume differences and surface gradients of temperature and solute concentration. Attention is focused on boundary layers that form along a vertical liquid-gas interface, when the appropriately defined nondimensional characteristic transport numbers are large enough, in problems of thermosolutal natural and Marangoni convection, such as buoyancy and surface tension driven flows in differentially heated open cavities and liquid bridges. Classes of similar solutions are derived for each class of convection on the basis of a rigorous order of magnitude analysis. Velocity, temperature and concentration profiles are reported in the similarity plane; flow and transport properties at the liquid-gas interface (interfacial velocity, heat and mass transfer bulk coefficients) are obtained for a wide range of Prandtl and Schmidt numbers and different values of the similarity parameter.

Does price efficiency increase with trading volume? Evidence of nonlinearity and power laws in ETFs

NASA Astrophysics Data System (ADS)

Caginalp, Gunduz; DeSantis, Mark

2017-02-01

Whether efficiency increases with increasing volume is an important issue that may illuminate trader strategies and distinguish between market theories. This relationship is tested using 124,236 daily observations comprising 68 large and liquid U.S. equity exchange traded funds (ETFs). ETFs have the advantage that efficiency can be measured in terms of the deviation between the trading price and the underlying net asset value that is reported each day. Our findings support the hypothesis that the relationship between volume and efficiency is nonlinear. Indeed, efficiency increases as volume increases from low to moderately high levels, but then decreases as volume increases further. The first part tends to support the idea that higher volume simply facilitates transactions and maintains efficiency, while the latter part, i.e., even higher volumes, supports the ansatz that increased volume is associated with increased speculation that ignores valuation and decreases efficiency. The results are consistent with the hypothesis that valuation is only part of the motivation for traders. Our methodology accounts for fund heterogeneity and contemporaneous correlations. Similar results are obtained when daily price volatility is introduced as an additional independent variable.

A zero power harmonic transponder sensor for ubiquitous wireless μL liquid-volume monitoring

NASA Astrophysics Data System (ADS)

Huang, Haiyu; Chen, Pai-Yen; Hung, Cheng-Hsien; Gharpurey, Ranjit; Akinwande, Deji

2016-01-01

Autonomous liquid-volume monitoring is crucial in ubiquitous healthcare. However, conventional approach is based on either human visual observation or expensive detectors, which are costly for future pervasive monitoring. Here we introduce a novel approach based on passive harmonic transponder antenna sensor and frequency hopping spread spectrum (FHSS) pattern analysis, to provide a very low cost wireless μL-resolution liquid-volume monitoring without battery or digital circuits. In our conceptual demonstration, the harmonic transponder comprises of a passive nonlinear frequency multiplier connected to a metamaterial-inspired 3-D antenna designed to be highly sensitive to the liquid-volume within a confined region. The transponder first receives some FHSS signal from an interrogator, then converts such signal to its harmonic band and re-radiates through the antenna sensor. The harmonic signal is picked up by a sniffer receiver and decoded through pattern analysis of the high dimensional FHSS signal strength data. A robust, zero power, absolute accuracy wireless liquid-volume monitoring is realized in the presence of strong direct coupling, background scatters, distance variance as well as near-field human-body interference. The concepts of passive harmonic transponder sensor, metamaterial-inspired antenna sensor, and FHSS pattern analysis based sensor decoding may help establishing cost-effective, energy-efficient and intelligent wireless pervasive healthcare monitoring platforms.

A zero power harmonic transponder sensor for ubiquitous wireless μL liquid-volume monitoring.

PubMed

Huang, Haiyu; Chen, Pai-Yen; Hung, Cheng-Hsien; Gharpurey, Ranjit; Akinwande, Deji

2016-01-06

Autonomous liquid-volume monitoring is crucial in ubiquitous healthcare. However, conventional approach is based on either human visual observation or expensive detectors, which are costly for future pervasive monitoring. Here we introduce a novel approach based on passive harmonic transponder antenna sensor and frequency hopping spread spectrum (FHSS) pattern analysis, to provide a very low cost wireless μL-resolution liquid-volume monitoring without battery or digital circuits. In our conceptual demonstration, the harmonic transponder comprises of a passive nonlinear frequency multiplier connected to a metamaterial-inspired 3-D antenna designed to be highly sensitive to the liquid-volume within a confined region. The transponder first receives some FHSS signal from an interrogator, then converts such signal to its harmonic band and re-radiates through the antenna sensor. The harmonic signal is picked up by a sniffer receiver and decoded through pattern analysis of the high dimensional FHSS signal strength data. A robust, zero power, absolute accuracy wireless liquid-volume monitoring is realized in the presence of strong direct coupling, background scatters, distance variance as well as near-field human-body interference. The concepts of passive harmonic transponder sensor, metamaterial-inspired antenna sensor, and FHSS pattern analysis based sensor decoding may help establishing cost-effective, energy-efficient and intelligent wireless pervasive healthcare monitoring platforms.

A zero power harmonic transponder sensor for ubiquitous wireless μL liquid-volume monitoring

PubMed Central

Huang, Haiyu; Chen, Pai-Yen; Hung, Cheng-Hsien; Gharpurey, Ranjit; Akinwande, Deji

2016-01-01

Autonomous liquid-volume monitoring is crucial in ubiquitous healthcare. However, conventional approach is based on either human visual observation or expensive detectors, which are costly for future pervasive monitoring. Here we introduce a novel approach based on passive harmonic transponder antenna sensor and frequency hopping spread spectrum (FHSS) pattern analysis, to provide a very low cost wireless μL-resolution liquid-volume monitoring without battery or digital circuits. In our conceptual demonstration, the harmonic transponder comprises of a passive nonlinear frequency multiplier connected to a metamaterial-inspired 3-D antenna designed to be highly sensitive to the liquid-volume within a confined region. The transponder first receives some FHSS signal from an interrogator, then converts such signal to its harmonic band and re-radiates through the antenna sensor. The harmonic signal is picked up by a sniffer receiver and decoded through pattern analysis of the high dimensional FHSS signal strength data. A robust, zero power, absolute accuracy wireless liquid-volume monitoring is realized in the presence of strong direct coupling, background scatters, distance variance as well as near-field human-body interference. The concepts of passive harmonic transponder sensor, metamaterial-inspired antenna sensor, and FHSS pattern analysis based sensor decoding may help establishing cost-effective, energy-efficient and intelligent wireless pervasive healthcare monitoring platforms. PMID:26732251

A perfluorochemical loss/restoration (L/R) system for tidal liquid ventilation.

PubMed

Libros, R; Philips, C M; Wolfson, M R; Shaffer, T H

2000-01-01

Tidal liquid ventilation is the transport of dissolved respiratory gases via volume exchange of perfluorochemical (PFC) liquid to and from the PFC-filled lung. All gas-liquid surface tension is eliminated, increasing compliance and providing lung protection due to lower inflation pressures. Tidal liquid ventilation is achieved by cycling fluid from a reservoir to and from the lung by a ventilator. Current approaches are microprocessor-based with feedback control. During inspiration, warmed oxygenated PFC liquid is pumped from a fluid reservoir/gas exchanger into the lung. PFC fluid is conserved by condensing (60-80% efficiency) vapor in the expired gas. A feedback-control system was developed to automatically replace PFC lost due to condenser inefficiency. This loss/restoration (L/R) system consists of a PFC-vapor thermal detector (+/- 2.5%), pneumatics, amplifiers, a gas flow detector (+/- 1%), a PFC pump (+/- 5%), and a controller. Gravimetric studies of perflubron loss from a flask due to evaporation were compared with experimental L/R results and found to be within +/- 1.4%. In addition, when L/R studies were conducted with a previously reported liquid ventilation system over a four-hour period, the L/R system maintained system perflubron volume to within +/- 1% of prime volume and 11.5% of replacement volume, and the difference between experimental PFC loss and that of the L/R system was 1.8 mL/hr. These studies suggest that the PFC L/R system may have significant economic (appropriate dosing for PFC loss) as well as physiologic (maintenance of PFC inventory in the lungs and liquid ventilator) impact on liquid ventilation procedures.

New PDLC materials obtained from dispersion of LC under microgravity

NASA Astrophysics Data System (ADS)

Matos, M. R.; Leitao, J. C.; Andre, R. M.; Zambujal, R.; Carmelo Rosa, Carla; Simeao Carvalho, P.; Podgorski, Thomas

Aknowledgements: This project has been supported by ESA-Education, the University of Porto, IFIMUP and INESC-Porto. Bibliography: [1] F Bloisi and L Vicari. Optical Applications of Liquid Crystals, chapter 4: Polymer-dispersed liquid crystals. Institute of Physics Publishing, 2003. [2] J. William Doane. Liquid Crystals Applications and Uses, volume 1, chapter 14: Polymer Dispersed Liquid Crystal Displays, pages 361-391. World Scientific, 1990. [3] K. Parbhakar, J. M. Jin, H. M. Nguyen, and L. H. Dao. Effect of microgravity on the distribution of liquid-crystal droplets dispersed in a polymer matrix. CHEMISTRY OF MA-TERIALS, 8(??):1210-1216, Jun 1996. [4] Paul S. Drzaic. Liquid Crystal Dispersions, volume 1. World Scientific, 1995.

Development, Fabrication, and Testing of a Liquid/Liquid Microchannel Heat Exchanger for Constellation Spacecrafts

NASA Technical Reports Server (NTRS)

Hawkins-Reynolds, Ebony; Le, Hung; Stephan, Ryan

2010-01-01

Microchannel technology can be incorporated into heat exchanger designs to decrease the mass and volume of space hardware. The National Aeronautics and Space Administration at the Johnson Space Center (NASA JSC) partnered with Pacific Northwest National Laboratories (PNNL) to develop a liquid/liquid microchannel heat exchanger that has significant mass and volume savings without sacrificing thermal and pressure drop performance. PNNL designed the microchannel heat exchanger to the same performance design requirements of a conventional plate and fin liquid/liquid heat exchanger; 3 kW duty with inlet temperatures of 26 C and 4 C. Both heat exchangers were tested using the same test parameters on a test apparatus and performance data compared.

[A simple model for describing pressure-volume curves in free balloon dilatation with reference the dynamics of inflation hydraulic aspects].

PubMed

Bloss, P; Werner, C

2000-06-01

We propose a simple model to describe pressure-time and pressure-volume curves for the free balloon (balloon in air) of balloon catheters, taking into account the dynamics of the inflation device. On the basis of our investigations of the flow rate-dependence of characteristic parameters of the pressure-time curves, the appropriateness of this simple model is demonstrated using a representative example. Basic considerations lead to the following assumptions: (1) the flow within the shaft of the catheter is laminar, and (ii) the volume decrease of the liquid used for inflation due to pressurization can be neglected if the liquid is carefully degassed prior to inflation, and if the total volume of the liquid in the system is less than 2 ml. Taking into account the dynamics of the inflation device used for pumping the liquid into the proximal end of the shaft during inflation, the inflation process can be subdivided into the following three phases: initial phase, filling phase and dilatation phase. For these three phases, the transformation of the time into the volume coordinates is given. On the basis of our model, the following parameters of the balloon catheter can be determined from a measured pressure-time curve: (1) the resistance to flow of the liquid through the shaft of the catheter and the resulting pressure drop across the shaft, (2) the residual volume and residual pressure of the balloon, and (3) the volume compliance of the balloon catheter with and without the inflation device.

Influence of liquid-volume and airflow rates on spray application quality and homogeneity in super-intensive olive tree canopies.

PubMed

Miranda-Fuentes, Antonio; Rodríguez-Lizana, Antonio; Gil, Emilio; Agüera-Vega, J; Gil-Ribes, Jesús A

2015-12-15

Olive is a key crop in Europe, especially in countries around the Mediterranean Basin. Optimising the parameters of a spray is essential for sustainable pesticide use, especially in high-input systems, such as the super-intensive hedgerow system. Parameters may be optimised by adjusting the applied volume and airflow rate of sprays, in addition to the liquid to air proportion and the relationship between air velocity and airflow rate. Two spray experiments using a commercial airblast sprayer were conducted in a super-intensive orchard to study how varying the liquid volume rate (testing volumes of 182, 619, and 1603 l ha(-1)) and volumetric airflow rate (with flow rates of 11.93, 8.90, and 6.15 m(3) s(-1)) influences the coverage parameters and the amount and distribution of deposits in different zones of the canopy.. Our results showed that an increase in the application volume raised the mean deposit and percentage coverage, but decreased the application efficiency, spray penetration, and deposit homogeneity. Furthermore, we found that the volumetric airflow rate had a lower influence on the studied parameters than the liquid volume; however, an increase in the airflow rate improved the application efficiency and homogeneity to a certain threshold, after which the spray quality decreased. This decrease was observed in the high-flow treatment. Our results demonstrate that intermediate liquid volume rates and volumetric airflow rates are required for the optimal spraying of pesticides on super-intensive olive crops, and would reduce current pollution levels. Copyright © 2015 Elsevier B.V. All rights reserved.

Physics of beer tapping.

PubMed

Rodríguez-Rodríguez, Javier; Casado-Chacón, Almudena; Fuster, Daniel

2014-11-21

The popular bar prank known in colloquial English as beer tapping consists in hitting the top of a beer bottle with a solid object, usually another bottle, to trigger the foaming over of the former within a few seconds. Despite the trick being known for a long time, to the best of our knowledge, the phenomenon still lacks scientific explanation. Although it seems natural to think that shock-induced cavitation enhances the diffusion of CO2 from the supersaturated bulk liquid into the bubbles by breaking them up, the subtle mechanism by which this happens remains unknown. Here, we show that the overall foaming-over process can be divided into three stages where different physical phenomena take place in different time scales: namely, the bubble-collapse (or cavitation) stage, the diffusion-driven stage, and the buoyancy-driven stage. In the bubble-collapse stage, the impact generates a train of expansion-compression waves in the liquid that leads to the fragmentation of preexisting gas cavities. Upon bubble fragmentation, the sudden increase of the interface-area-to-volume ratio enhances mass transfer significantly, which makes the bubble volume grow by a large factor until CO2 is locally depleted. At that point buoyancy takes over, making the bubble clouds rise and eventually form buoyant vortex rings whose volume grows fast due to the feedback between the buoyancy-induced rising speed and the advection-enhanced CO2 transport from the bulk liquid to the bubble. The physics behind this explosive process sheds insight into the dynamics of geological phenomena such as limnic eruptions.

Physics of Beer Tapping

NASA Astrophysics Data System (ADS)

Rodríguez-Rodríguez, Javier; Casado-Chacón, Almudena; Fuster, Daniel

2014-11-01

The popular bar prank known in colloquial English as beer tapping consists in hitting the top of a beer bottle with a solid object, usually another bottle, to trigger the foaming over of the former within a few seconds. Despite the trick being known for a long time, to the best of our knowledge, the phenomenon still lacks scientific explanation. Although it seems natural to think that shock-induced cavitation enhances the diffusion of CO2 from the supersaturated bulk liquid into the bubbles by breaking them up, the subtle mechanism by which this happens remains unknown. Here, we show that the overall foaming-over process can be divided into three stages where different physical phenomena take place in different time scales: namely, the bubble-collapse (or cavitation) stage, the diffusion-driven stage, and the buoyancy-driven stage. In the bubble-collapse stage, the impact generates a train of expansion-compression waves in the liquid that leads to the fragmentation of preexisting gas cavities. Upon bubble fragmentation, the sudden increase of the interface-area-to-volume ratio enhances mass transfer significantly, which makes the bubble volume grow by a large factor until CO2 is locally depleted. At that point buoyancy takes over, making the bubble clouds rise and eventually form buoyant vortex rings whose volume grows fast due to the feedback between the buoyancy-induced rising speed and the advection-enhanced CO2 transport from the bulk liquid to the bubble. The physics behind this explosive process sheds insight into the dynamics of geological phenomena such as limnic eruptions.

Precipitation of thin-film organic single crystals by a novel crystal growth method using electrospray and ionic liquid film

NASA Astrophysics Data System (ADS)

Ueda, Hiroyuki; Takeuchi, Keita; Kikuchi, Akihiko

2018-04-01

We report an organic single crystal growth technique, which uses a nonvolatile liquid thin film as a crystal growth field and supplies fine droplets containing solute from the surface of the liquid thin film uniformly and continuously by electrospray deposition. Here, we investigated the relationships between the solute concentration of the supplied solution and the morphology and size of precipitated crystals for four types of fluorescent organic low molecule material [tris(8-hydroxyquinoline)aluminum (Alq3), 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD), N,N‧-bis(3-methylphenyl)-N,N‧-diphenylbenzidine (TPD), and N,N-bis(naphthalene-1-yl)-N,N-diphenyl-benzidine (NPB)] using an ionic liquid as the nonvolatile liquid. As the concentration of the supplied solution decreased, the morphology of precipitated crystals changed from dendritic or leaf shape to platelike one. At the solution concentration of 0.1 mg/ml, relatively large platelike single crystals with a diagonal length of over 100 µm were obtained for all types of material. In the experiment using ionic liquid and dioctyl sebacate as nonvolatile liquids, it was confirmed that there is a clear positive correlation between the maximum volume of the precipitated single crystal and the solubility of solute under the same solution supply conditions.

The liquid⟷amorphous transition and the high pressure phase diagram of carbon

NASA Astrophysics Data System (ADS)

Robinson, David R.; Wilson, Mark

2013-04-01

The phase diagram of carbon is mapped to high pressure using a computationally-tractable potential model. The use of a relatively simple (Tersoff-II) potential model allows a large range of phase space to be explored. The coexistence (melting) curve for the diamond crystal/liquid dyad is mapped directly by modelling the solid/liquid interfaces. The melting curve is found to be re-entrant and belongs to a conformal class of diamond/liquid coexistence curves. On supercooling the liquid a phase transition to a tetrahedral amorphous form (ta-C) is observed. The liquid ⟷ amorphous coexistence curve is mapped onto the pT plane and is found to also be re-entrant. The entropy changes for both melting and the amorphous ⟶ liquid transitions are obtained from the respective coexistence curves and the associated changes in molar volume. The structural change on amorphization is analysed at different points on the coexistence curve including for transitions that are both isochoric and isocoordinate (no change in nearest-neighbour coordination number). The conformal nature of the melting curve is highlighted with respect to the known behaviour of Si. The relationship of the observed liquid/amorphous coexistence curve to the Si low- and high-density amorphous (LDA/HDA) transition is discussed.

Design of a Very Large Pulse Tube Cryocooler for HTS Cable Application

NASA Astrophysics Data System (ADS)

Tanchon, J.; Ercolani, E.; Trollier, T.; Ravex, A.; Poncet, J. M.

2006-04-01

The needs for large cooling powers are more and more increasing together with the increase of superconductor capabilities. Within the framework of an High Voltage HTS cable project (LIPA project funded by the DOE with American Superconductor AMSC, Nexans, LIPA and Air Liquide as consortium partners), the Technologies & Innovation Department of Air Liquide with the partnership of the CEA/SBT are currently developing a prototype of a Very Large Pulse Tube Cooler (VLPTC). This prototype is traditionally based on an In-Line pulse tube configuration, making use of an inertance and a buffer volume as phase shifter. The expected performances are 280W heat lift at 65K with a 300K rejection temperature. The cold head prototype has been manufactured and preliminary tests have been carried out with a 8 kW flexure bearing Stirling Technology Corporation STC linear compressor. One of the objectives of this prototype is to compete the Gifford-MacMahon coolers in term of cooling capacity while offering the advantage of the high frequency Pulse Tube in term of high lifetime, reliability and reduced exported vibrations.

Catalyst for coal liquefaction process

DOEpatents

Huibers, Derk T. A.; Kang, Chia-Chen C.

1984-01-01

An improved catalyst for a coal liquefaction process; e.g., the H-Coal Process, for converting coal into liquid fuels, and where the conversion is carried out in an ebullated-catalyst-bed reactor wherein the coal contacts catalyst particles and is converted, in addition to liquid fuels, to gas and residual oil which includes preasphaltenes and asphaltenes. The improvement comprises a catalyst selected from the group consisting of the oxides of nickel molybdenum, cobalt molybdenum, cobalt tungsten, and nickel tungsten on a carrier of alumina, silica, or a combination of alumina and silica. The catalyst has a total pore volume of about 0.500 to about 0.900 cc/g and the pore volume comprises micropores, intermediate pores and macropores, the surface of the intermediate pores being sufficiently large to convert the preasphaltenes to asphaltenes and lighter molecules. The conversion of the asphaltenes takes place on the surface of micropores. The macropores are for metal deposition and to prevent catalyst agglomeration. The micropores have diameters between about 50 and about 200 angstroms (.ANG.) and comprise from about 50 to about 80% of the pore volume, whereas the intermediate pores have diameters between about 200 and 2000 angstroms (.ANG.) and comprise from about 10 to about 25% of the pore volume, and the macropores have diameters between about 2000 and about 10,000 angstroms (.ANG.) and comprise from about 10 to about 25% of the pore volume. The catalysts are further improved where they contain promoters. Such promoters include the oxides of vanadium, tungsten, copper, iron and barium, tin chloride, tin fluoride and rare earth metals.

The Relative Roles of Passive Surface Forces and Active Ion Transport in the Modulation of Airway Surface Liquid Volume and Composition

PubMed Central

Tarran, Robert; Grubb, Barbara R.; Gatzy, John T.; Davis, C. William; Boucher, Richard C.

2001-01-01

Two hypotheses have been proposed recently that offer different views on the role of airway surface liquid (ASL) in lung defense. The “compositional” hypothesis predicts that ASL [NaCl] is kept low (<50 mM) by passive forces to permit antimicrobial factors to act as a chemical defense. The “volume” hypothesis predicts that ASL volume (height) is regulated isotonically by active ion transport to maintain efficient mechanical mucus clearance as the primary form of lung defense. To compare these hypotheses, we searched for roles for: (1) passive forces (surface tension, ciliary tip capillarity, Donnan, and nonionic osmolytes) in the regulation of ASL composition; and (2) active ion transport in ASL volume regulation. In primary human tracheobronchial cultures, we found no evidence that a low [NaCl] ASL could be produced by passive forces, or that nonionic osmolytes contributed substantially to ASL osmolality. Instead, we found that active ion transport regulated ASL volume (height), and that feedback existed between the ASL and airway epithelia to govern the rate of ion transport and volume absorption. The mucus layer acted as a “reservoir” to buffer periciliary liquid layer height (7 μm) at a level optimal for mucus transport by donating or accepting liquid to or from the periciliary liquid layer, respectively. These data favor the active ion transport/volume model hypothesis to describe ASL physiology. PMID:11479349

Impact Detection for Characterization of Complex Multiphase Flows

NASA Astrophysics Data System (ADS)

Chan, Wai Hong Ronald; Urzay, Javier; Mani, Ali; Moin, Parviz

2016-11-01

Multiphase flows often involve a wide range of impact events, such as liquid droplets impinging on a liquid pool or gas bubbles coalescing in a liquid medium. These events contribute to a myriad of large-scale phenomena, including breaking waves on ocean surfaces. As impacts between surfaces necessarily occur at isolated points, numerical simulations of impact events will require the resolution of molecular scales near the impact points for accurate modeling. This can be prohibitively expensive unless subgrid impact and breakup models are formulated to capture the effects of the interactions. The first step in a large-eddy simulation (LES) based computational methodology for complex multiphase flows like air-sea interactions requires effective detection of these impact events. The starting point of this work is a collision detection algorithm for structured grids on a coupled level set / volume of fluid (CLSVOF) solver adapted from an earlier algorithm for cloth animations that triangulates the interface with the marching cubes method. We explore the extension of collision detection to a geometric VOF solver and to unstructured grids. Supported by ONR/A*STAR. Agency of Science, Technology and Research, Singapore; Office of Naval Research, USA.

The effect of perfluorocarbon vapour on the measurement of respiratory tidal volume during partial liquid ventilation.

PubMed

Davies, M W; Dunster, K R

2000-08-01

During partial liquid ventilation perfluorocarbon vapour is present in the exhaled gases. The volumes of these gases are measured by pneumotachometers. Error in measuring tidal volumes will give erroneous measurement of lung compliance during partial liquid ventilation. We aim to compare measured tidal volumes with and without perfluorocarbon vapour using tidal volumes suitable for use in neonates. Tidal volumes were produced with a 100 ml calibration syringe from 20 to 100 ml and with a calibrated Harvard rodent ventilator from 2.5 to 20 ml. Control tidal volumes were drawn from a humidifier chamber containing water vapour and the PFC tidal volumes were drawn from a humidifier chamber containing water and perfluorocarbon (FC-77) vapour. Tidal volumes were measured by a fixed orifice, target, differential pressure flowmeter (VenTrak) or a hot-wire anenometer (Bear Cub) placed between the calibration syringe or ventilator and the humidifier chamber. All tidal volumes measured with perfluorocarbon vapour were increased compared with control (ANOVA p < 0.001 and post t-test p < 0.0001). Measured tidal volume increased from 7 to 16% with the fixed orifice type flow-meter, and from 35 to 41% with the hot-wire type. In conclusion, perfluorocarbon vapour flowing through pneumotachometers gives falsely high tidal volume measurements. Calculation of lung compliance must take into account the effect of perfluorocarbon vapour on the measurement of tidal volume.

Direct large volume injection ultra-high performance liquid chromatography-tandem mass spectrometry determination of artificial sweeteners sucralose and acesulfame in well water.

PubMed

Wu, Minghuo; Qian, Yichao; Boyd, Jessica M; Hrudey, Steve E; Le, X Chris; Li, Xing-Fang

2014-09-12

Acesulfame (ACE) and sucralose (SUC) have become recognized as ideal domestic wastewater contamination indicators. Liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) analysis is commonly used; however, the sensitivity of SUC is more than two orders of magnitude lower than that of ACE, limiting the routine monitoring of SUC. To address this issue, we examined the ESI behavior of both ACE and SUC under various conditions. ACE is ionic in aqueous solution and efficiently produces simple [M-H](-) ions, but SUC produces multiple adduct ions, limiting its sensitivity. The formic acid (FA) adducts of SUC [M+HCOO](-) are sensitively and reproducibly generated under the LC-MS conditions. When [M+HCOO](-) is used as the precursor ion for SUC detection, the sensitivity increases approximately 20-fold compared to when [M-H](-) is the precursor ion. To further improve the limit of detection (LOD), we integrated the large volume injection approach (500μL injection) with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), which reduced the method detection limit (MDL) to 0.2ng/L for ACE and 5ng/L for SUC. To demonstrate the applicability of this method, we analyzed 100 well water samples collected in Alberta. ACE was detected in 24 wells at concentrations of 1-1534ng/L and SUC in 8 wells at concentrations of 65-541ng/L. These results suggest that wastewater is the most likely source of ACE and SUC impacts in these wells, suggesting the need for monitoring the quality of domestic well water. Copyright © 2014 Elsevier B.V. All rights reserved.

Measurement of the airway surface liquid volume with simple light refraction microscopy.

PubMed

Harvey, Peter R; Tarran, Robert; Garoff, Stephen; Myerburg, Mike M

2011-09-01

In the cystic fibrosis (CF) lung, the airway surface liquid (ASL) volume is depleted, impairing mucus clearance from the lung and leading to chronic airway infection and obstruction. Several therapeutics have been developed that aim to restore normal airway surface hydration to the CF airway, yet preclinical evaluation of these agents is hindered by the paucity of methods available to directly measure the ASL. Therefore, we sought to develop a straightforward approach to measure the ASL volume that would serve as the basis for a standardized method to assess mucosal hydration using readily available resources. Primary human bronchial epithelial (HBE) cells cultured at an air-liquid interface develop a liquid meniscus at the edge of the culture. We hypothesized that the size of the fluid meniscus is determined by the ASL volume, and could be measured as an index of the epithelial surface hydration status. A simple method was developed to measure the volume of fluid present in meniscus by imaging the refraction of light at the ASL interface with the culture wall using low-magnification microscopy. Using this method, we found that primary CF HBE cells had a reduced ASL volume compared with non-CF HBE cells, and that known modulators of ASL volume caused the predicted responses. Thus, we have demonstrated that this method can detect physiologically relevant changes in the ASL volume, and propose that this novel approach may be used to rapidly assess the effects of airway hydration therapies in high-throughput screening assays.

Determination of endocrine disrupting chemicals and antiretroviral compounds in surface water: A disposable sorptive sampler with comprehensive gas chromatography - Time-of-flight mass spectrometry and large volume injection with ultra-high performance liquid chromatography-tandem mass spectrometry.

PubMed

Wooding, Madelien; Rohwer, Egmont R; Naudé, Yvette

2017-05-05

Many rural dwellers and inhabitants of informal settlements in South Africa are without access to treated water and collect untreated water from rivers and dams for personal use. Endocrine disrupting chemicals (EDCs) have been detected in surface water and wildlife of South Africa. EDCs are often present in complex environmental matrices at ultra-trace levels complicating detection thereof. We report a simplified multi-residue approach for the detection and quantification of EDCs, emerging EDCs, and antiretroviral drugs in surface water. A low cost (less than one US dollar), disposable, sorptive extraction sampler was prepared in-house. The disposable samplers consisted of polydimethylsiloxane (PDMS) tubing fashioned into a loop which was then placed in water samples to concentrate EDCs and emerging pollutants. The PDMS samplers were thermally desorbed directly in the inlet of a GC, thereby eliminating the need for expensive consumable cryogenics. Comprehensive gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOFMS) was used for compound separation and identification. Linear retention indices of EDCs and emerging pollutants were determined on a proprietary Crossbond ® phase Rtx ® -CLPesticides II GC capillary column. In addition, large volume injection of surface water into an ultra-performance liquid chromatograph tandem mass spectrometer (UPLC-MS/MS) was used as complementary methodology for the detection of less volatile compounds. Large volume injection reduced tedious and costly sample preparation steps. Limits of detection for the GC method ranged from 1 to 98pg/l and for the LC method from 2 to 135ng/l. Known and emerging EDCs such as pharmaceuticals, personal care products and pesticides, as well as the antiretroviral compounds, efavirenz and nevirapine, were detected in surface water from South Africa at concentration levels ranging from 0.16ng/l to 227ng/l. Copyright © 2017 Elsevier B.V. All rights reserved.

A highly addressable static droplet array enabling digital control of a single droplet at pico-volume resolution.

PubMed

Jeong, Heon-Ho; Lee, Byungjin; Jin, Si Hyung; Jeong, Seong-Geun; Lee, Chang-Soo

2016-04-26

Droplet-based microfluidics enabling exquisite liquid-handling has been developed for diagnosis, drug discovery and quantitative biology. Compartmentalization of samples into a large number of tiny droplets is a great approach to perform multiplex assays and to improve reliability and accuracy using a limited volume of samples. Despite significant advances in microfluidic technology, individual droplet handling in pico-volume resolution is still a challenge in obtaining more efficient and varying multiplex assays. We present a highly addressable static droplet array (SDA) enabling individual digital manipulation of a single droplet using a microvalve system. In a conventional single-layer microvalve system, the number of microvalves required is dictated by the number of operation objects; thus, individual trap-and-release on a large-scale 2D array format is highly challenging. By integrating double-layer microvalves, we achieve a "balloon" valve that preserves the pressure-on state under released pressure; this valve can allow the selective releasing and trapping of 7200 multiplexed pico-droplets using only 1 μL of sample without volume loss. This selectivity and addressability completely arranged only single-cell encapsulated droplets from a mixture of droplet compositions via repetitive selective trapping and releasing. Thus, it will be useful for efficient handling of miniscule volumes of rare or clinical samples in multiplex or combinatory assays, and the selective collection of samples.

Earth, soil and environmental science research facility at sector 13 of the Advanced Photon Source. II. Scientific program and experimental instrumentation (abstract)

NASA Astrophysics Data System (ADS)

Sutton, S.; Eng., P. J.; Jaski, Y. R.; Lazaraz, N.; Pluth, J.; Murray, P.; Rarback, H.; Rivers, M.

1996-09-01

The GSECARS (APS sector 13) scientific program will provide fundamental new information on the deep structure and composition of the Earth and other planets, the formation of economic mineral deposits, the cycles and fate of toxic metals in the environment, and the mechanisms of nutrient uptake and disease in plants. In the four experimental stations (2 per beamline), scientists will have access to three main x-ray techniques: diffraction (microcrystal, powder, diamond anvil cell, and large volume press), fluorescence microprobe, and spectroscopy (conventional, microbeam, liquid and solid surfaces). The high pressure facilities will be capable of x-ray crystallography at P≳360 GPa and T˜6000 K with the diamond anvil cell and P˜25 GPa and T˜2500 °C with the large volume press. Diffractometers will allow study of 1 micrometer crystals and micro-powders. The microprobe (1 micrometer focused beam) will be capable of chemical analyses in the sub-ppm range using wavelength and energy dispersive detectors. Spectroscopy instrumentation will be available for XANES and EXAFS with microbeams as well as high sensitivity conventional XAS and studies of liquid and solid interfaces. Visiting scientists will be able to setup, calibrate, and test experiments in off-line laboratories with equipment such as micromanipulators, optical microscopes, clean bench, glove boxes, high powered optical and Raman spectrometers.

Novel Laser Ablation Technology for Surface Decontamination

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

Cheng, Chung H.

2004-06-01

Laser ablation for surface cleaning has been pursued for the removal of paint on airplanes. It has also been pursued for the cleaning of semiconductor surfaces. However, all these approaches have been pursued by laser ablation in air. For highly contaminated surface, laser ablation in air can easily cause secondary contamination. Thus it is not suitable to apply to achieve surface decontamination for DOE facilities since many of these facilities have radioactive contaminants on the surface. Any secondary contamination will be a grave concern. The objective of this project is to develop a novel technology for laser ablation in liquidmore » for surface decontamination. It aims to achieve more efficient surface decontamination without secondary contamination and to evaluate the economic feasibility for large scale surface decontamination with laser ablation in liquid. When laser ablation is pursued in the solution, all the desorbed contaminants will be confined in liquid. The contaminants can be precipitated and subsequently contained in a small volume for disposal. It can reduce the risk of the decontamination workers. It can also reduce the volume of contaminants dramatically.« less

Upgrade plans for the ATLAS Forward Calorimeter at the HL-LHC

NASA Astrophysics Data System (ADS)

Rutherfoord, John; ATLAS Liquid Argon Calorimeter Group

2012-12-01

Although data-taking at CERN's Large Hadron Collider (LHC) is expected to continue for a number of years, plans are already being developed for operation of the LHC and associated detectors at an increased instantaneous luminosity about 5 times the original design value of 1034 cm-2 s-1. The increased particle flux at this high luminosity (HL) will have an impact on many sub-systems of the ATLAS detector. In particular, in the liquid argon forward calorimeter (FCal), which was designed for operation at LHC luminosities, the associated increase in the ionization load at HL-LHC luminosities creates a number of problems which can degrade its performance. These include space-charge effects in the liquid argon gaps, excessive drop in potential across the gaps due to large HV supply currents through the protection resistors, and an increase in temperature which may cause the liquid argon to boil. One solution, which would require opening both End-Cap cryostats, is the construction and installation of new FCals with narrower liquid argon gaps, lowering the values of the protection resistors, and the addition of cooling loops. A second proposed solution, which does not require opening the cryostat cold volume, is the addition of a small, warm calorimeter in front of each existing FCal, resulting in a reduction of the particle flux to levels at which the existing FCal can operate normally.

Sensitive assay for measurement of volatile borneol, isoborneol, and the metabolite camphor in rat pharmacokinetic study of Borneolum (Bingpian) and Borneolum syntheticum (synthetic Bingpian)

PubMed Central

Cheng, Chen; Liu, Xin-wei; Du, Fei-fei; Li, Mei-juan; Xu, Fang; Wang, Feng-qing; Liu, Yang; Li, Chuan; Sun, Yan

2013-01-01

Aim: Both Borneolum (Chinese name Bingpian; dextrorotatory borneol) and Borneolum syntheticum (synthetic Bingpian; a mixture of optically inactive borneol and isoborneol) have been used for medicinal purposes in Chinese traditional medicine. The aim of this study was to develop a sensitive assay for measuring volatile ingredients borneol, isoborneol, and their metabolite camphor in pharmacokinetic study of Bingpian. Methods: Rat plasma samples were prepared using liquid-liquid microextraction: 70 μL of plasma sample (containing 125 nmol/L naphthalene as the internal standard) was extracted with 35 μL of n-hexane. The resulting n-hexane extract (20 μL) was introduced into a gas chromatography/mass spectrometry system using programmable temperature vaporizing-based large-volume injection. The assay was validated to demonstrate its reliability for the intended use. Using this assay, pharmacokinetic studies of Bingpian, synthetic Bingpian, and Fufang-Danshen tablets (containing synthetic Bingpian) were conducted in rats. Results: The extraction efficiency for the analytes and the internal standard from plasma was almost constant with decrease in n-hexane-to-plasma volume ratio, thus enabling a small volume of extracting solvent to be used for sample preparation, and enhancing the assay sensitivity. The lower quantification limit for measuring borneol, isoborneol, and camphor in plasma was 0.98 nmol/L, which was 33–330 times more sensitive than those reported earlier for Bingpian and synthetic Bingpian. The applicability of the miniaturized liquid-liquid extraction technique could be extended to measure other volatile and nonvolatile medicinal compounds in biomatrices, which can be predicted according to the analytes' octanol/water distribution coefficient (logD) and acid dissociation constant (pKa). Conclusion: This assay is sensitive, accurate and free of matrix effects, and can be applied to pharmacokinetic studies of Bingpian, synthetic Bingpian, and Bingpian-containing herbal products. PMID:23974515

Determination of Alternaria mycotoxins in wine and juice using ionic liquid modified countercurrent chromatography as a pretreatment method followed by high-performance liquid chromatography.

PubMed

Fan, Chen; Cao, Xueli; Liu, Man; Wang, Wei

2016-03-04

Alternariol (AOH), alternariol monomethyl ether (AME), and tenuazonic acid (TeA) are some of the main Alternaria mycotoxins that can be found as contaminants in food materials. The objective of this study was to develop a pretreatment method with countercurrent chromatography (CCC) for enrichment and cleanup of trace Alternaria mycotoxins in food samples prior to high-performance liquid chromatography (HPLC) analysis. An Analytical CCC instrument with a column volume 22.5mL was used, and a two-phase solvent system composed of ethyl acetate and water modified with 6% [HOOMIM][Cl] in mass to volume ratio was selected. Under the optimized CCC operation conditions, trace amounts of AOH, AME, and TeA in large volume of liquid sample were efficiently extracted and enriched in the stationary phase, and then eluted out just by reversing the stationary phase as mobile phase in the opposite flowing direction tail-to-head. The enrichment and elution strategies are unique and can be fulfilled online with high enrichment factors (87-114) and high recoveries (81.14-110.94%). The method has been successively applied to the determination of Alternaria mycotoxins in real apple juice and wine samples with the limits of detection (LOD) in the range of 0.03-0.14μgL(-1). Totally 12 wine samples and 15 apple juice samples from the local market were analyzed. The detection rate of AOH and AME in both kinds of the samples were more than 50%, while TeA was found in relatively high level of 1.75-49.61μgL(-1) in some of the apple juice samples. The proposed method is simple, rapid, and sensitive and could also be used for the analysis and monitoring of Alternaria mycotoxin in other food samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Experimental and simulation studies on grain growth in TiC and WC-based cermets during liquid phase sintering

NASA Astrophysics Data System (ADS)

Shin, Soon-Gi

2000-06-01

The grain growth behaviors of TiC and WC particles in TiC-Ni, TiC-Mo2C-Ni, WC-Co and WC-VC-Co alloys during liquid phase sintering were investigated for different Ni or Co contents and compared with the results of Monte Carlo simulations. In the experimental study, TiC-Ni and WC-Co alloys had a maximum grain size at a certain liquid volume fraction, while the grain size in TiC-Mo2C-Ni and WC-VC-Co alloys increased monotonically with an increasing liquid volume fraction. These results mean that the grain growth of these alloys cannot be explained by the conventional mechanisms for Ostwald ripening, namely diffusion or reaction controlled processes. Monte Carlo simulations with different energy relationships between solidliquid interfaces predicted the effect of the liquid volume fraction on grain size similar to the experimental results. The contiguous boundaries between solid (carbide) particles appear to influence the grain growth behavior in TiC- and WC-based alloys during liquid phase sintering.

Confinement of surface waves at the air-water interface to control aerosol size and dispersity

NASA Astrophysics Data System (ADS)

Nazarzadeh, Elijah; Wilson, Rab; King, Xi; Reboud, Julien; Tassieri, Manlio; Cooper, Jonathan M.

2017-11-01

The precise control over the size and dispersity of droplets, produced within aerosols, is of great interest across many manufacturing, food, cosmetic, and medical industries. Amongst these applications, the delivery of new classes of high value drugs to the lungs has recently attracted significant attention from pharmaceutical companies. This is commonly achieved through the mechanical excitation of surface waves at the air liquid interface of a parent liquid volume. Previous studies have established a correlation between the wavelength on the surface of liquid and the final aerosol size. In this work, we show that the droplet size distribution of aerosols can be controlled by constraining the liquid inside micron-sized cavities and coupling surface acoustic waves into different volumes of liquid inside micro-grids. In particular, we show that by reducing the characteristic physical confinement size (i.e., either the initial liquid volume or the cavities' diameters), higher harmonics of capillary waves are revealed with a consequent reduction of both aerosol mean size and dispersity. In doing so, we provide a new method for the generation and fine control of aerosols' sizes distribution.

Preferred numbers and the distributions of trade sizes and trading volumes in the Chinese stock market

NASA Astrophysics Data System (ADS)

Mu, G.-H.; Chen, W.; Kertész, J.; Zhou, W.-X.

2009-03-01

The distributions of trade sizes and trading volumes are investigated based on the limit order book data of 22 liquid Chinese stocks listed on the Shenzhen Stock Exchange in the whole year 2003. We observe that the size distribution of trades for individualstocks exhibits jumps, which is caused by the number preference of traders when placing orders. We analyze the applicability of the “q-Gamma” function for fitting the distribution by the Cramér-von Mises criterion. The empirical PDFs of tradingvolumes at different timescales Δt ranging from 1 min to 240 min can be well modeled. The applicability of the q-Gamma functions for multiple trades is restricted to the transaction numbers Δn≤ 8. We find that all the PDFs have power-law tails for large volumes. Using careful estimation of the average tail exponents α of the distributions of trade sizes and trading volumes, we get α> 2, well outside the Lévy regime.

Medical and Scientific Evaluations aboard the KC-135. Microgravity-Compatible Flow Cytometer

NASA Technical Reports Server (NTRS)

Crucian, Brian; Nelman-Gonzalez, Mayra; Sams, Clarence

2005-01-01

A spaceflight-compatible flow cytometer would be useful for the diagnosis of astronaut illness during long duration spaceflight and for conducting in-flight research to evaluate the effects of microgravity on human physiology. Until recently, the primary limitations preventing the development of a spaceflight compatible flow cytometer have been largely mechanical. Standard commercially available flow cytometers are large, complex instruments that use high-energy lasers and require significant training to operate. Standard flow cytometers function by suspending the particles to be analyzed inside a sheath fluid for analysis. This requires the presence of several liters of sheath fluid for operation, and generates a corresponding amount of liquid hazardous waste. The particles are then passed through a flow cell which uses the fluid mechanical property of hydrodynamic focusing to place the cells in single-file (laminar flow) as they pass through a laser beam for scanning and evaluation. Many spaceflight experiments have demonstrated that fluid physics is dramatically altered in microgravity (MSF [Manned Space Flight] Fluid Physics Data Sheet-August 1997) and previous studies have shown that sheath-fluid based hydrodynamic focusing may also be altered during microgravity (Crucian et al, 2000). For these reasons it is likely that any spaceflight compatible design for a flow cytometer would abandon the sheath fluid requirement. The elimination of sheath fluid would remove both the problems of weight associated with large volumes of liquids as well as the large volume of liquid waste generated. It would also create the need for a method to create laminar particle flow distinct from the standard sheath-fluid based method. The spaceflight prototype instrument is based on a recently developed commercial flow cytometer possessing a novel flow cell design that creates single-particle laser scanning and evaluation without the need for sheath-fluid based hydrodynamic focusing. This instrument also possesses a number of design advances that make it conditionally microgravity compatible: it is highly miniaturized and lightweight, uses a low energy diode laser, has a small number of moving parts, does not use sheath fluid and does not generate significant liquid waste. Although possessing certain limitations, the commercial cytometer functions operationally like a standard bench top laboratory flow cytometer, aspirating liquid particle samples and generating histogram or dot-plot data in standard FCS file format. In its current configuration however, the cytometer is limited to three parameter/two-color capability (two color PMTs + forward scatter), does not allow compensation between colors, does not allow linear analysis and is operated by rather inflexible software with limited capabilities. This is due to the fact that the cytometer has been designed and marketed as an instrument specific to a few particular assays, not as a multipurpose cytometer.

Preventing Raman Lasing in High-Q WGM Resonators

NASA Technical Reports Server (NTRS)

Savchenkov, Anatoliy; Matsko, Andrey; Strekalov, Dmitry; Maleki, Lute

2007-01-01

A generic design has been conceived to suppress the Raman effect in whispering- gallery-mode (WGM) optical resonators that have high values of the resonance quality factor (Q). Although it is possible to exploit the Raman effect (even striving to maximize the Raman gain to obtain Raman lasing), the present innovation is intended to satisfy a need that arises in applications in which the Raman effect inhibits the realization of the full potential of WGM resonators as frequency-selection components. Heretofore, in such applications, it has been necessary to operate high-Q WGM resonators at unattractively low power levels to prevent Raman lasing. (The Raman-lasing thresholds of WGM optical resonators are very low and are approximately proportional to Q(sup -2)). Heretofore, two ways of preventing Raman lasting at high power levels have been known, but both entail significant disadvantages: A resonator can be designed so that the optical field is spread over a relatively large mode volume to bring the power density below the threshold. For any given combination of Q and power level, there is certain mode volume wherein Raman lasing does not start. Unfortunately, a resonator that has a large mode volume also has a high spectral density, which is undesirable in a typical photonic application. A resonator can be cooled to the temperature of liquid helium, where the Raman spectrum is narrower and, therefore, the Raman gain is lower. However, liquid-helium cooling is inconvenient. The present design overcomes these disadvantages, making it possible to operate a low-spectral-density (even a single-mode) WGM resonator at a relatively high power level at room temperature, without risk of Raman lasing.

Rapid and sensitive screening and selective quantification of antibiotics in human urine by two-dimensional ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.

PubMed

Wang, He-Xing; Wang, Bin; Zhou, Ying; Jiang, Qing-Wu

2014-12-01

A rapid and sensitive method for the screening and selective quantification of antibiotics in urine by two-dimensional ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was developed. This method allowed the injection of 200 μL urine extract. The 200-μL injection volume used in this method increased the absolute sensitivity for target antibiotics in solvent by an average 13.3 times, with a range from 8.4 to 28.5 times, compared with the 10-μL conventional injection volume. A 96-well solid phase extraction procedure was established to eliminate the contamination on the chromatographic column resulting from the large-volume injection and increase the throughput of sample preparation. Fourteen target antibiotics from six common categories (β-lactams, quinolones, tetracyclines, macrolides, sulfonamides, and chloramphenicols) were selected as model compounds, and a database containing an additional 74 antibiotics was compiled for posttarget screening. The limit of detection of the target antibiotics, defined as a signal-to-noise ratio of 3, ranged from 0.04 to 1.99 ng/mL. The mean interday recoveries ranged between 79.6 and 121.3 %, with a relative standard deviation from 2.9 to 18.3 % at three spiking levels of 20 ng/mL, 50 ng/mL, and 100 ng/mL. This method was successfully applied in 60 real urine samples from schoolchildren aged 8-11 years, and four target antibiotics (azithromycin, sulfadiazine, trimethoprim, and oxytetracycline) and two posttarget antibiotics (sulfadimidine and cefaclor) were found in the urine samples. This method can be used as a large-scale biomonitoring tool for exposure of the human population to antibiotics.

The Effect of Thermal Cycling on Crystal-Liquid Separation During Lunar Magma Ocean Differentiation

NASA Technical Reports Server (NTRS)

Mills, Ryan D.

2013-01-01

Differentiation of magma oceans likely involves a mixture of fractional and equilibrium crystallization [1]. The existence of: 1) large volumes of anorthosite in the lunar highlands and 2) the incompatible- rich (KREEP) reservoir suggests that fractional crystallization may have dominated during differentiation of the Moon. For this to have occurred, crystal fractionation must have been remarkably efficient. Several authors [e.g. 2, 3] have hypothesized that equilibrium crystallization would have dominated early in differentiation of magma oceans because of crystal entrainment during turbulent convection. However, recent numerical modeling [4] suggests that crystal settling could have occurred throughout the entire solidification history of the lunar magma ocean if crystals were large and crystal fraction was low. These results indicate that the crystal size distribution could have played an important role in differentiation of the lunar magma ocean. Here, I suggest that thermal cycling from tidal heating during lunar magma ocean crystallization caused crystals to coarsen, leading to efficient crystal-liquid separation.

Large-eddy simulation of turbulent cavitating flow in a micro channel

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

Egerer, Christian P., E-mail: christian.egerer@aer.mw.tum.de; Hickel, Stefan; Schmidt, Steffen J.

2014-08-15

Large-eddy simulations (LES) of cavitating flow of a Diesel-fuel-like fluid in a generic throttle geometry are presented. Two-phase regions are modeled by a parameter-free thermodynamic equilibrium mixture model, and compressibility of the liquid and the liquid-vapor mixture is taken into account. The Adaptive Local Deconvolution Method (ALDM), adapted for cavitating flows, is employed for discretizing the convective terms of the Navier-Stokes equations for the homogeneous mixture. ALDM is a finite-volume-based implicit LES approach that merges physically motivated turbulence modeling and numerical discretization. Validation of the numerical method is performed for a cavitating turbulent mixing layer. Comparisons with experimental data ofmore » the throttle flow at two different operating conditions are presented. The LES with the employed cavitation modeling predicts relevant flow and cavitation features accurately within the uncertainty range of the experiment. The turbulence structure of the flow is further analyzed with an emphasis on the interaction between cavitation and coherent motion, and on the statistically averaged-flow evolution.« less

Linking the structures, free volumes, and properties of ionic liquid mixtures† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc01407d

PubMed Central

Brooks, Nicholas J.; Castiglione, Franca; Doherty, Cara M.; Dolan, Andrew; Hill, Anita J.; Hunt, Patricia A.; Matthews, Richard P.; Mauri, Michele; Mele, Andrea; Simonutti, Roberto; Villar-Garcia, Ignacio J.; Weber, Cameron C.

2017-01-01

The formation of ionic liquid (IL) mixtures has been proposed as an approach to rationally fine-tune the physicochemical properties of ILs for a variety of applications. However, the effects of forming such mixtures on the resultant properties of the liquids are only beginning to be understood. Towards a more complete understanding of both the thermodynamics of mixing ILs and the effect of mixing these liquids on their structures and physicochemical properties, the spatial arrangement and free volume of IL mixtures containing the common [C4C1im]+ cation and different anions have been systematically explored using small angle X-ray scattering (SAXS), positron annihilation lifetime spectroscopy (PALS) and 129Xe NMR techniques. Anion size has the greatest effect on the spatial arrangement of the ILs and their mixtures in terms of the size of the non-polar domains and inter-ion distances. It was found that differences in coulombic attraction between oppositely charged ions arising from the distribution of charge density amongst the atoms of the anion also significantly influences these inter-ion distances. PALS and 129Xe NMR results pertaining to the free volume of these mixtures were found to strongly correlate with each other despite the vastly different timescales of these techniques. Furthermore, the excess free volumes calculated from each of these measurements were in excellent agreement with the excess volumes of mixing measured for the IL mixtures investigated. The correspondence of these techniques indicates that the static and dynamic free volume of these liquid mixtures are strongly linked. Consequently, fluxional processes such as hydrogen bonding do not significantly contribute to the free volumes of these liquids compared to the spatial arrangement of ions arising from their size, shape and coulombic attraction. Given the relationship between free volume and transport properties such as viscosity and conductivity, these results provide a link between the structures of IL mixtures, the thermodynamics of mixing and their physicochemical properties. PMID:29619199

Detecting Aspiration and Penetration Using FEES With and Without Food Dye.

PubMed

Marvin, Stevie; Gustafson, Sara; Thibeault, Susan

2016-08-01

The objective of this investigation was to determine if there were differences in identifying airway invasion (penetration or aspiration) during fiberoptic endoscopic evaluations of swallowing (FEES) for green-dyed versus non-dyed liquids. Forty adult inpatients in an acute care hospital underwent FEES, with both green-dyed liquids and naturally white liquids. Three speech-language pathologists rated aspiration and penetration for trials of nectar-thick milk and thin milk, both with and without green food dye. A subset of participants having excess pharyngeal/laryngeal secretions, as measured by the Secretions Severity Scale, were also analyzed for a difference in the detection of airway invasion and pharyngeal residue. No significant differences were found between dyes in airway invasion across all bolus types within participants. Significant differences were found in penetration ratings for large volumes of thin liquids (90 ml), between participants. When examining only discrepant airway invasion judgments for green-white swallow pairs, statistically significantly deeper airway invasion was measured for green-dyed boluses versus white for three of the five bolus types. Repeat rater reliability was better for dyed versus undyed liquids. Findings suggest that the use of green dye may allow for improved judgment of airway invasion.

Microwave-assisted synthesis of gold, silver, platinum and palladium nanostructures and their use in electrocatalytic applications.

PubMed

Safavi, Afsaneh; Tohidi, Maryam

2014-09-01

Microwave-assisted ionic liquid method was used for synthesis of various noble metals, such as gold, silver, platinum and palladium nanomaterials. This route does not employ any template agent, surface capping agents or reducing agents. The process is fast, simple and of high yield. Different metal precursors in various ionic liquids media (1-butyl-3-methylimidazolium tetrafluoroborate, octyl pyridinium hexaflurophosphate and 1-octyl-3-methylimidazolium hexaflurophosphate) were applied to produce metal nanomaterials. Silver, platinium and palladium nanoparticles exhibit spherical morphology while nanosheets with high aspect ratio were obtained for gold. These metal nanostructures were incorporated into a carbon ionic liquid electrode to investigate their electrocatalytic properties. It was found that synthesis in different ionic liquids result in different activity. Excellent electrocatalytic effects toward adenine, hydrazine, formaldehyde and ethanol were observed for the modified electrodes with different nanoparticles synthesized in 1-butyl-3-methylimidazolium tetrafluoroborate. The high conductivity, large surface-to-volume ratio and active sites of nanosized metal particles are responsible for their electrocatalytic activity. In contrast, the carbon ionic liquid electrode modified with synthesized metal nanoparticles in octyl pyridinium hexaflurophosphate and 1-octyl-3-methylimidazolium hexaflurophosphate showed negligible activity for detection of these probes.

Pressure Dependence of Komatiite Liquid Viscosity and Implications for Magma Ocean Rheology

NASA Astrophysics Data System (ADS)

O'Dwyer Brown, L.; Lesher, C. E.; Terasaki, H. G.; Yamada, A.; Sakamaki, T.; Shibazaki, Y.; Ohtani, E.

2009-12-01

The viscosities of komatiite liquids at high pressures and temperatures were investigated using the in-situ falling sphere technique at BL04B1, SPring-8. Komatiites are naturally occurring magmas, rich in network modifying cations. Despite the refractory and fluid nature of komatiite, we successfully measured the viscosity of molten komatiites from Gorgona Island, Colombia (MgO = 17.8 wt.%; NBO/T = 1.5) between 11 and 13 GPa at 2000 C, and from Belingwe, Zimbabwe (MgO = 28.14 wt.%; NBO/T = 2.1) from 12 to 14 GPa at 2000 C. Under isothermal conditions, the viscosity of Gorgona Island komatiite melt increased with pressure, consistent with our previous measurements at lower pressures for this composition. We interpreted this positive pressure dependence as the result of reductions in interatomic space diminishing the free volume of the liquid when compressed. The viscosity of molten komatiite from Belingwe also increased up to 12 GPa, however between 12 and 14 GPa the viscosity is nearly constant. In previous studies of depolymerized silicate liquids, the pressure dependence of viscosity has been shown to reverse from positive to negative between 8 and 10 GPa with corresponding changes in activation volume [1] [2]. In contrast, the activation volume for Belingwe liquid decreases to near zero, but does not become negative above 11 GPa. Similarly, the activation volume for Gorgona Island komatiite remains positive throughout the pressure range investigated. Molecular dynamics simulations of simple MgO-SiO2 liquids with NBO/T > 2 also show a positive pressure dependence, reflecting the dominant control of free-volume reduction on the viscosity of depolymerized melts. However, the more rapid reduction in activation volume with pressure in komatiite liquids may be related to the presence of Al, Ti and other cations that interact and undergo coordination changes unavailable in simple silicate liquids. Along Hadean and post-Hadean mantle adiabats the net effect of temperature and pressure on ultramafic liquids suggests that changes in viscosity are likely modest and viscosity will decrease with depth. Stiffening and isolation of the lower regions of a magma ocean due to increasing melt viscosity seem unlikely. [1] PEPI (2003) 139, 45 [2] EPSL (2005) 240, 589

Mechanical tuning of the evaporation rate of liquid on crossed fibers.

PubMed

Boulogne, François; Sauret, Alban; Soh, Beatrice; Dressaire, Emilie; Stone, Howard A

2015-03-17

We investigate experimentally the drying of a small volume of perfectly wetting liquid on two crossed fibers. We characterize the drying dynamics for the three liquid morphologies that are encountered in this geometry: drop, column, and a mixed morphology, in which a drop and a column coexist. For each morphology, we rationalize our findings with theoretical models that capture the drying kinetics. We find that the evaporation rate significantly depends upon the liquid morphology and that the drying of the liquid column is faster than the evaporation of the drop and the mixed morphology for a given liquid volume. Finally, we illustrate that shearing a network of fibers reduces the angle between them, changes the morphology toward the column state, and therefore, enhances the drying rate of a volatile liquid deposited on it.

30 CFR 36.26 - Composition of exhaust gas.

Code of Federal Regulations, 2010 CFR

2010-07-01

... immediately at full load and speed. The preliminary liquid-fuel-injection rate shall be such that the exhaust... adverse conditions disclosed by preliminary tests. (b) Final engine adjustment. The liquid fuel supply to... percent, by volume, of carbon monoxide or 0.20 percent, by volume, of oxides of nitrogen (calculated as...

Hydrocarbon Gas Liquids (HGL): Recent Market Trends and Issues

EIA Publications

2014-01-01

Over the past five years, rapid growth in U.S. onshore natural gas and oil production has led to increased volumes of natural gas plant liquids (NGPL) and liquefied refinery gases (LRG). The increasing economic importance of these volumes, as a result of their significant growth in production, has revealed the need for better data accuracy and transparency to improve the quality of historical data and projections for supply, demand, and prices of these liquids, co-products, and competing products. To reduce confusion in terminology and improve its presentation of data, EIA has worked with industry and federal and state governments to clarify gas liquid terminology and has developed the term Hydrocarbon Gas Liquids, or HGL.

Dielectric Properties of Low-Level Liquid Waste

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

L. E. Lagos; M. A. Ebadian

1998-10-20

The purpose of this study was to develop a data collection containing values for the dielectric properties of various low-level liquid waste (LLLW) simulants measured as a function of frequency, temperature, and composition. The investigation was motivated by current interest in the use of microwave processing for the treatment of radioactive waste. A large volume of transuranic liquid and sludge produced by the U.S. Department of Defense (DOD) during the production of nuclear fiel bars is stored at several U.S. Department of Energy (DOE) sites around the United States. Waste storage and disposal space is scarce, expensive, and must bemore » minimized. Thus, several DOE sites are pursuing the use of microwave heating as a means of achieving volume reduction and solidification of low-level liquid wastes. It is important to know which microwave frequencies should be employed tc achieve the most efficient processing at a range of different temperatures. The dielectric properties of the LLLW simulants can be utilized to determine the optimum frequencies for use with a particular LLLW or with other LLLWS of similar composition. Furthermore, nonlinear thermal processes, such as thermal runaway, which occur in the material being treated cannot be modeled without a knowledge of the temperature dependence of the dielectric properties. Often, this data does not exist; however, when it does, only very limited data near room temperature are available. The data collection generated in this study can be used to predict the behavior of a variety of microwave thermal treatment technologies, which have the potential of substantially reducing the volume of the LLLWS that are currently stored at many DOE sites. This information should help the users of the microwave reduction and solidification technology to optimize microwave processes used in the treatment of LLLW. The microwave reduction and solidification technology has clear advantages over other methods of reducing LLLWS. These include the incineration of combustibles, the evaporation of combustibles, the evaporation of liquids, and the compaction of noncombustibles. The handling of radioactive liquid waste is generally carried out within closed systems consisting of highly corrosion-resistant, welded, leak-tight pipes, tanks, and other apparatus. High power microwave processing is a promising technology for reducing risks to the environment and human health, thereby supporting the DOE's decontamination and decommissioning (D&D) objectives.« less

Cavitation studies in microgravity

NASA Astrophysics Data System (ADS)

Kobel, Philippe; Obreschkow, Danail; Farhat, Mohamed; Dorsaz, Nicolas; de Bosset, Aurele

The hydrodynamic cavitation phenomenon is a major source of erosion for many industrial systems such as cryogenic pumps for rocket propulsion, fast ship propellers, hydraulic pipelines and turbines. Erosive processes are associated with liquid jets and shockwaves emission fol-lowing the cavity collapse. Yet, fundamental understanding of these processes requires further cavitation studies inside various geometries of liquid volumes, as the bubble dynamics strongly depends the surrounding pressure field. To this end, microgravity represents a unique platform to produce spherical fluid geometries and remove the hydrostatic pressure gradient induced by gravity. The goal of our first experiment (flown on ESA's parabolic flight campaigns 2005 and 2006) was to study single bubble dynamics inside large spherical water drops (having a radius between 8 and 13 mm) produced in microgravity. The water drops were created by a micro-pump that smoothly expelled the liquid through a custom-designed injector tube. Then, the cavitation bubble was generated through a fast electrical discharge between two electrodes immersed in the liquid from above. High-speed imaging allowed to analyze the implications of isolated finite volumes and spherical free surfaces on bubble evolution, liquid jets formation and shock wave dynamics. Of particular interest are the following results: (A) Bubble lifetimes are shorter than in extended liquid volumes, which could be explain by deriving novel corrective terms to the Rayleigh-Plesset equation. (B) Transient crowds of micro-bubbles (smaller than 1mm) appeared at the instants of shockwaves emission. A comparison between high-speed visualizations and 3D N-particle simulations of a shock front inside a liquid sphere reveals that focus zones within the drop lead to a significantly increased density of induced cavitation. Considering shock wave crossing and focusing may hence prove crucially useful to understand the important process of cavitation erosion. The aim of our future microgravity experiment is to assess the direct effects of gravity on cavitation bubble collapse through a comparison of single cavitation bubbles collapsing in mi-crogravity, normal gravity, and hypergravity. In particular, we shall investigate the shape of the bubble in its final collapse stage and the amount of energy dissipated in the dominant collapse channels, such as liquid jet, shock wave, and rebound bubble. The highly spherical bubbles will be produced via a point-like plasma generated by a high power laser beam. One major hypothesis that we will test is an increase in shock wave energy with decreasing gravity as a consequence of the higher final sphericity and suppression of liquid jets. To support this, we introduce an analytical model for the gravity-perturbed asymmetric collapse of spherical bubbles, and demonstrate that all initially spherical bubbles develop a gravity-related vertical jet along their collapse.

One-step displacement dispersive liquid-liquid microextraction coupled with graphite furnace atomic absorption spectrometry for the selective determination of methylmercury in environmental samples.

PubMed

Liang, Pei; Kang, Caiyan; Mo, Yajun

2016-01-01

A novel method for the selective determination of methylmercury (MeHg) was developed by one-step displacement dispersive liquid-liquid microextraction (D-DLLME) coupled with graphite furnace atomic absorption spectrometry. In the proposed method, Cu(II) reacted with diethyldithiocarbamate (DDTC) to form Cu-DDTC complex, which was used as the chelating agent instead of DDTC for the dispersive liquid-liquid microextraction (DLLME) of MeHg. Because the stability of MeHg-DDTC is higher than that of Cu-DDTC, MeHg can displace Cu from the Cu-DDTC complex and be preconcentrated in a single DLLME procedure. MeHg could be extracted into the extraction solvent phase at pH 6 while Hg(II) remained in the sample solution. Potential interference from co-existing metal ions with lower DDTC complex stability was largely eliminated without the need of any masking reagent. Under the optimal conditions, the limit of detection of this method was 13.6ngL(-1) (as Hg), and an enhancement factor of 81 was achieved with a sample volume of 5.0mL. The proposed method was successfully applied for the determination of trace MeHg in some environmental samples with satisfactory results. Copyright © 2015 Elsevier B.V. All rights reserved.

Optimizing lung aeration at birth using a sustained inflation and positive pressure ventilation in preterm rabbits

PubMed Central

te Pas, Arjan B.; Kitchen, Marcus J.; Lee, Katie; Wallace, Megan J.; Fouras, Andreas; Lewis, Robert A.; Yagi, Naoto; Uesugi, Kentaro; Hooper, Stuart B.

2016-01-01

Background: A sustained inflation (SI) facilitates lung aeration, but the most effective pressure and duration are unknown. We investigated the effect of gestational age (GA) and airway liquid volume on the required inflation pressure and SI duration. Methods: Rabbit kittens were delivered at 27, 29, and 30 d gestation, intubated and airway liquid was aspirated. Either no liquid (control) or 30 ml/kg of liquid was returned to the airways. Lung gas volumes were measured by plethysmography and phase-contrast X-ray-imaging. Starting at 22 cmH2O, airway pressure was increased until airflow commenced and pressure was then held constant. The SI was truncated when 20 ml/kg air had entered the lung and ventilation continued with intermittent positive pressure ventilation (iPPV). Results: Higher SI pressures and longer durations were required in 27-d kittens compared to 30-d kittens. During iPPV, 27-d kittens needed higher pressures and had lower functional residual capacity (FRC) compared to 30-d kittens. Adding lung liquid increased SI duration, reduced FRC, and increased resistance and pressures during iPPV in 29- and 30-d kittens. Conclusion: Immature kittens required higher starting pressures and longer SI durations to achieve a set inflation volume. Larger airway liquid volumes adversely affected lung function during iPPV in older but not young kittens. PMID:26991259

Hybrid energy storage systems utilizing redox active organic compounds

DOEpatents

Wang, Wei; Xu, Wu; Li, Liyu; Yang, Zhenguo

2015-09-08

Redox flow batteries (RFB) have attracted considerable interest due to their ability to store large amounts of power and energy. Non-aqueous energy storage systems that utilize at least some aspects of RFB systems are attractive because they can offer an expansion of the operating potential window, which can improve on the system energy and power densities. One example of such systems has a separator separating first and second electrodes. The first electrode includes a first current collector and volume containing a first active material. The second electrode includes a second current collector and volume containing a second active material. During operation, the first source provides a flow of first active material to the first volume. The first active material includes a redox active organic compound dissolved in a non-aqueous, liquid electrolyte and the second active material includes a redox active metal.

Endoscope system with plasma flushing and coaxial round jet nozzle for off-pump cardiac surgery.

PubMed

Horiuchi, Tetsuya; Masamune, Ken; Iwase, Yuki; Ymashita, Hiromasa; Tsukihara, Hiroyuki; Motomura, Noboru; Ohta, Yuji; Dohi, Takeyoshi

2011-07-01

To develop a new endoscope for performing simple surgical tasks inside the blood-filled cardiac atrium/chamber, that is, "off-pump" cardiac surgeries. We developed the endoscope system with plasma flushing and coaxial round jet nozzle. The "plasma flushing" system was invented to observe the interior of the blood-filled heart by displacing blood cells in front of the endoscope tip. However, some areas could not be observed with simple flushing of the liquid because the flushed liquid mixed with blood. Further, a large amount of liquid had to be flushed, which posed a risk of cardiac damage caused by excess volume. Therefore, to safely capture high-resolution images of the interior of the heart, an endoscope with a coaxial round jet nozzle through which plasma is flushed has been developed. And to reduce the volume of flushed liquid, the synchronization system of heartbeat and the endoscope system with plasma flushing has been developed. We conducted an in vivo experiment to determine whether we could observe intracardiac tissues in swine without the use of a heart-lung machine. As a result, we successfully observed intracardiac tissues without using a heart-lung machine. By using a coaxial nozzle, we could even observe the tricuspid valve. Moreover, we were able to save up to 30% of the flushed liquid by replacing the original system with a synchronization system. And we evaluated the performance of the endoscope with the coaxial round jet nozzle by conducting fluid analysis and an in vitro experiment. We successfully observed intracardiac tissues without using a heart-lung machine. By using a coaxial nozzle, we could even observe the tricuspid valve. And by replacing an original system to a synchronization system, we were able to save up to 30% of the flushed liquid. As a follow-up study, we plan to create a surgical flexible device for valve disease that can grasp, staple, and repair cardiac valves by endoscopic visualization.

Effect of atomic size on undercoolability of binary solid solution alloy liquids with Zr, Ti, and Hf using electrostatic levitation

NASA Astrophysics Data System (ADS)

Jeon, S.; Kang, D.-H.; Lee, Y. H.; Lee, S.; Lee, G. W.

2016-11-01

We investigate the relationship between the excess volume and undercoolability of Zr-Ti and Zr-Hf alloy liquids by using electrostatic levitation. Unlike in the case of Zr-Hf alloy liquids in which sizes of the constituent atoms are matched, a remarkable increase of undercoolability and negative excess volumes are observed in Zr-Ti alloy liquids as a function of their compositional ratios. In this work, size mismatch entropies for the liquids were obtained by calculating their hard sphere diameters, number densities, and packing fractions. We also show that the size mismatch entropy, which arises from the differences in atomic sizes of the constituent elements, plays an important role in determining the stabilities of metallic liquids.

Near-critical fluid boiling: overheating and wetting films.

PubMed

Hegseth, J; Oprisan, A; Garrabos, Y; Lecoutre-Chabot, C; Nikolayev, V S; Beysens, D

2008-08-01

The heating of coexisting gas and liquid phases of pure fluid through its critical point makes the fluid extremely compressible, expandable, slows the diffusive transport, and decreases the contact angle to zero (perfect wetting by the liquid phase). We have performed experiments on near-critical fluids in a variable volume cell in the weightlessness of an orbiting space vehicle, to suppress buoyancy-driven flows and gravitational constraints on the liquid-gas interface. The high compressibility, high thermal expansion, and low thermal diffusivity lead to a pronounced adiabatic heating called the piston effect. We have directly visualized the near-critical fluid's boundary layer response to a volume quench when the external temperature is held constant. We have found that when the system's temperature T is increased at a constant rate past the critical temperature T(c), the interior of the fluid gains a higher temperature than the hot wall (overheating). This extends previous results in temperature quenching experiments in a similarly prepared system when the gas is clearly isolated from the wall. Large elliptical wetting film distortions are also seen during these ramps. By ray tracing through the elliptically shaped wetting film, we find very thick wetting film on the walls. This wetting film is at least one order of magnitude thicker than films that form in the Earth's gravity. The thick wetting film isolates the gas bubble from the wall allowing gas overheating to occur due to the difference in the piston effect response between gas and liquid. Remarkably, this overheating continues and actually increases when the fluid is ramped into the single-phase supercritical phase.

Driving self-assembly and emergent dynamics in colloidal suspensions by time-dependent magnetic fields

DOE PAGES

Martin, James E.; Snezhko, Alexey

2013-11-05

In this review we discuss recent research on driving self assembly of magnetic particle suspensions subjected to alternating magnetic fields. The variety of structures and effects that can be induced in such systems is remarkably broad due to the large number of variables involved. The alternating field can be uniaxial, biaxial or triaxial, the particles can be spherical or anisometric, and the suspension can be dispersed throughout a volume or confined to a soft interface. In the simplest case the field drives the static or quasi-static assembly of unusual particle structures, such as sheets, networks and open-cell foams. More complex,more » emergent collective behaviors evolve in systems that can follow the time-dependent field vector. In these cases energy is continuously injected into the system and striking °ow patterns and structures can arise. In fluid volumes these include the formation of advection and vortex lattices. At air-liquid and liquid-liquid interfaces striking dynamic particle assemblies emerge due to the particle-mediated coupling of the applied field to surface excitations. These out-of-equilibrium interface assemblies exhibit a number of remarkable phenomena, including self-propulsion and surface mixing. In addition to discussing various methods of driven self assembly in magnetic suspensions, some of the remarkable properties of these novel materials are described.« less

LLE review. Volume 61, Quarterly report, October--December 1994

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

NONE

1994-12-31

This volume of the LLE review, covering the period of October--December 1994, contains articles on a diagnostic method employing krypton spectroscopy for measurement of temperature and shell-fuel mixing in high-temperature implosions; the first direct assessment of the ion-acoustic decay instability in a large-scale length, hot plasma; measurements of polarization mode dispersion and group-velocity walkaway in birefringent media using a frequency domain interferometer; an evaluation of the magnetic flux dynamics occurring in an optically triggered, thin-film superconducting switch; the effect of slurry fluid chemistry on particle size distribution during aqueous polishing of optical glass; and the influence of thermal and mechanicalmore » processing history in the preparation of well-ordered liquid crystal elastomer systems.« less

Apparatus for Sampling Surface Contamination

NASA Technical Reports Server (NTRS)

Wells, Mark

2008-01-01

An apparatus denoted a swab device has been developed as a convenient means of acquiring samples of contaminants from surfaces and suspending the samples in liquids. (Thereafter, the liquids can be dispensed, in controlled volumes, into scientific instruments for analysis of the contaminants.) The swab device is designed so as not to introduce additional contamination and to facilitate, simplify, and systematize the dispensing of controlled volumes of liquid into analytical instruments. The swab device is a single apparatus into which are combined all the equipment and materials needed for sampling surface contamination. The swab device contains disposable components stacked together on a nondisposable dispensing head. One of the disposable components is a supply cartridge holding a sufficient volume of liquid for one complete set of samples. (The liquid could be clean water or another suitable solvent, depending on the application.) This supply of liquid is sealed by Luer valves. At the beginning of a sampling process, the user tears open a sealed bag containing the supply cartridge. A tip on the nondisposable dispensing head is engaged with a Luer valve on one end of the supply cartridge and rotated, locking the supply cartridge on the dispensing head and opening the valve. The swab tip includes a fabric swab that is wiped across the surface of interest to acquire a sample. A sealed bag containing a disposable dispensing tip is then opened, and the swab tip is pushed into the dispensing tip until seated. The dispensing head contains a piston that passes through a spring-loaded lip seal. The air volume displaced by this piston forces the liquid out of the supply cartridge, over the swab, and into the dispensing tip. The piston is manually cycled to enforce oscillation of the air volume and thereby to cause water to flow to wash contaminants from the swab and cause the resulting liquid suspension of contaminants to flow into the dispensing tip. After several cycles to ensure adequate mixing, liquid containing the suspended contaminant sample is dispensed. The disposable components are then removed from the dispensing head, which may then be reused with a fresh set of disposable components.

Solvation behaviour of L-leucine in aqueous ionic liquid at different temperatures: Volumetric approach

NASA Astrophysics Data System (ADS)

Sharma, Samriti; Sandarve, Sharma, Amit K.; Sharma, Meena

2018-05-01

For the investigation of interactions of L-leucine in aqueous solutions of an ionic liquid (1-butyl-3-methylimidazolium tetra fluoroborate [Bmim][BF4]) at atmospheric pressure over a temperature range of (293.15K to 313.16K), we use the volumetric approach. By using the density data we have calculated the apparent molar volume, VΦ, limiting apparent molar volume, V0Φ, the slope, Sv, partial molar volume of transfer, V0Φ,tr. The values of these acoustical parameters have been used for the interpretation of different interactions like hydrophilic-hydrophilic, hydrophilic-hydrophobic, ion hydrophilic, solute-solvent and solute-solute interactions in the amino acid and ionic liquid solutions.

Extraterrestrial processing and manufacturing of large space systems, volume 2, chapters 7-14 and appendices

NASA Technical Reports Server (NTRS)

Miller, R. H.; Smith, D. B. S.

1979-01-01

Production and support equipment specifications are described for the space manufacturing facility (SMF). Defined production equipment includes electromagnetic pumps for liquid metal, metal alloying furnaces, die casters, electron beam welders and cutters, glass forming for structural elements, and rolling. A cost analysis is presented which includes the development, the aquisition of all SMF elements, initial operating cost, maintenance and logistics cost, cost of terrestrial materials, and transportation cost for each major element. Computer program listings and outputs are appended.

Estimating Residual Solids Volume In Underground Storage Tanks

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

Clark, Jason L.; Worthy, S. Jason; Martin, Bruce A.

2014-01-08

The Savannah River Site liquid waste system consists of multiple facilities to safely receive and store legacy radioactive waste, treat, and permanently dispose waste. The large underground storage tanks and associated equipment, known as the 'tank farms', include a complex interconnected transfer system which includes underground transfer pipelines and ancillary equipment to direct the flow of waste. The waste in the tanks is present in three forms: supernatant, sludge, and salt. The supernatant is a multi-component aqueous mixture, while sludge is a gel-like substance which consists of insoluble solids and entrapped supernatant. The waste from these tanks is retrieved andmore » treated as sludge or salt. The high level (radioactive) fraction of the waste is vitrified into a glass waste form, while the low-level waste is immobilized in a cementitious grout waste form called saltstone. Once the waste is retrieved and processed, the tanks are closed via removing the bulk of the waste, chemical cleaning, heel removal, stabilizing remaining residuals with tailored grout formulations and severing/sealing external penetrations. The comprehensive liquid waste disposition system, currently managed by Savannah River Remediation, consists of 1) safe storage and retrieval of the waste as it is prepared for permanent disposition; (2) definition of the waste processing techniques utilized to separate the high-level waste fraction/low-level waste fraction; (3) disposition of LLW in saltstone; (4) disposition of the HLW in glass; and (5) closure state of the facilities, including tanks. This paper focuses on determining the effectiveness of waste removal campaigns through monitoring the volume of residual solids in the waste tanks. Volume estimates of the residual solids are performed by creating a map of the residual solids on the waste tank bottom using video and still digital images. The map is then used to calculate the volume of solids remaining in the waste tank. The ability to accurately determine a volume is a function of the quantity and quality of the waste tank images. Currently, mapping is performed remotely with closed circuit video cameras and still photograph cameras due to the hazardous environment. There are two methods that can be used to create a solids volume map. These methods are: liquid transfer mapping / post transfer mapping and final residual solids mapping. The task is performed during a transfer because the liquid level (which is a known value determined by a level measurement device) is used as a landmark to indicate solids accumulation heights. The post transfer method is primarily utilized after the majority of waste has been removed. This method relies on video and still digital images of the waste tank after the liquid transfer is complete to obtain the relative height of solids across a waste tank in relation to known and usable landmarks within the waste tank (cooling coils, column base plates, etc.). In order to accurately monitor solids over time across various cleaning campaigns, and provide a technical basis to support final waste tank closure, a consistent methodology for volume determination has been developed and implemented at SRS.« less

The use of chilled condensers for the recovery of perfluorocarbon liquid in an experimental model of perfluorocarbon vapour loss during neonatal partial liquid ventilation

PubMed Central

Dunster, Kimble R; Davies, Mark W; Fraser, John F

2007-01-01

Background Perfluorocarbon (PFC) vapour in the expired gases during partial liquid ventilation should be prevented from entering the atmosphere and recovered for potential reuse. This study aimed to determine how much PFC liquid could be recovered using a conventional humidified neonatal ventilator with chilled condensers in place of the usual expiratory ventilator circuit and whether PFC liquid could be recovered when using the chilled condensers at the ventilator exhaust outlet. Methods Using a model lung, perfluorocarbon vapour loss during humidified partial liquid ventilation of a 3.5 kg infant was approximated. For each test 30 mL of FC-77 was infused into the model lung. Condensers were placed in the expiratory limb of the ventilator circuit and the amounts of PFC (FC-77) and water recovered were measured five times. This was repeated with the condensers placed at the ventilator exhaust outlet. Results When the condensers were used as the expiratory limb, the mean (± SD) volume of FC77 recovered was 16.4 mL (± 0.18 mL). When the condensers were connected to the ventilator exhaust outlet the mean (± SD) volume of FC-77 recovered was 7.6 mL (± 1.14 mL). The volume of FC-77 recovered was significantly higher when the condenser was used as an expiratory limb. Conclusion Using two series connected condensers in the ventilator expiratory line 55% of PFC liquid (FC-77) can be recovered during partial liquid ventilation without altering the function of the of the ventilator circuit. This volume of PFC recovered was just over twice that recovered with the condensers connected to the ventilator exhaust outlet. PMID:17537270

The dependency of expiratory airway collapse on pump system and flow rate in liquid ventilated rabbits.

PubMed

Meinhardt, J P; Ashton, B A; Annich, G M; Quintel, M; Hirschl, R B

2003-05-30

To evaluate the influence of pump system and flow pattern on expiratory airway collapse (EAC) in total perfluorocarbon ventilation. - Prospective, controlled, randomized animal trial for determination of (1) post-mortem changes by repeated expiration procedures (EP) with a constant flow piston pump (PP) before and after sacrifice (n = 8 rabbits), (2) differences between pump systems by subjecting animals to both PP and roller pump (RP) circuits for expiration (n = 16 rabbits). EP were performed using a servo-controlled shut-off at airway pressures < 25 cm H subset 2O randomly with either pump at different flows. - Expired volumes before and after sacrifice were not significantly different. PP and RP revealed identical mean flows, while significantly more liquid was drained using PP (p<0.05). Increasing differences towards higher flow rates indicated profound flow pulsatility in RP. - (1) post-mortem changes in expired volumes are not significant, (2) EAC is related to flow rate and pump system; (3) relationship between expiratory flow rate and drainable liquid volume is linear inverse; (4) PP provides higher drainage than RP. - Expiratory airway collapse is related to flow rate and pump system, post mortem changes in expirable volumes are not significant. Relationship between expiratory flow rate and drainable liquid volume is linear inverse, piston pump expiration provides higher drainage volumes than roller pump expiration.

Development and Design of Zero-g Liquid Quantity Gauge for Solar Thermal Vehicle

NASA Technical Reports Server (NTRS)

Dodge, Franklin T.; Green, Steven T.; Petullo, Steven P.; VanDresar, Neil T.

2002-01-01

The development and design of a cryogenic liquid quantity gauge for zero-gravity (zero-g) applications are described. The gauge, named the compression mass gauge (CMG), operates on the principle of slightly changing the volume of the tank by an oscillating bellows. The resulting pressure change is measured and used to predict the volume of vapor in the tank, from which the volume of liquid is computed. For each gauging instance, pressures are measured for several different bellows frequencies to enable minor real-gas effects to be quantified and thereby to obtain a gauging accuracy of 11 percent of tank volume. The CMG has been selected by NASA's Future-X program for a flight demonstration on the United States Air Force-Boeing Solar Orbit Transfer Vehicle Space Experiment (SOTVSE). This report reviews the design trade studies needed for the CMG to satisfy the SOTVSE limitations on its power, volume, and mass and also describes the mechanical design of the CMG.

High-resolution three-dimensional magnetic resonance imaging of mouse lung in situ.

PubMed

Scadeng, Miriam; Rossiter, Harry B; Dubowitz, David J; Breen, Ellen C

2007-01-01

This study establishes a method for high-resolution isotropic magnetic resonance (MR) imaging of mouse lungs using tracheal liquid-instillation to remove MR susceptibility artifacts. C57BL/6J mice were instilled sequentially with perfluorocarbon and phosphate-buffered saline to an airway pressure of 10, 20, or 30 cm H2O. Imaging was performed in a 7T MR scanner using a 2.5-cm Quadrature volume coil and a 3-dimensional (3D) FLASH imaging sequence. Liquid-instillation removed magnetic susceptibility artifacts and allowed lung structure to be viewed at an isotropic resolution of 78-90 microm. Instilled liquid and modeled lung volumes were well correlated (R = 0.92; P < 0.05) and differed by a constant tissue volume (220 +/- 92 microL). 3D image renderings allowed differences in structural dimensions (volumes and areas) to be accurately measured at each inflation pressure. These data demonstrate the efficacy of pulmonary liquid instillation for in situ high-resolution MR imaging of mouse lungs for accurate measurement of pulmonary airway, parenchymal, and vascular structures.

In-plane pitch control of cholesteric liquid crystals by formation of artificial domains via patterned photopolymerization.

PubMed

Yoshida, Hiroyuki; Miura, Yusuke; Tokuoka, Kazuki; Suzuki, Satoshi; Fujii, Akihiko; Ozaki, Masanori

2008-11-10

A controlled helix pitch modulation in the in-plane direction of a planarly aligned cholesteric liquid crystal cell is demonstrated by using photopolymerizable cholesteric liquid crystals. By fabricating artificial domains with a closed volume via two-photon excitation laser-lithography, the degree of pitch modulation could be controlled by adjusting the surface area to volume ratio of the domain. A pitch modulation of over 60 nm was realized by designing the shape of the artificial domain.

IMPROVEMENTS IN LIQUID-LIQUID EXTRACTION APPARATUS

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

None

1961-06-28

A description is given of a liquid-liquid extraction apparatus and of the method of effecting a net transportation in opposed directions of a heavy liquid and a light liquid. The apparatus consists of a plurality of series- connected ves sels, inlet and outlet means for the phases at the ends, and a pulsing means. The upper part of one vessel is joined to the lower part of the next vessel by one connection line or a plurality of parallel-connected lines. The lower part of the second vessel is below the upper part of the first vessel. The volume of eachmore » connection line is less than or the same as the volume displaced by one stroke of the pulsing means. The method is characterized in that a mixture of both liquids is caused to flow to and fro between adjacent vessels through the connection lines which joins the vessels. (N.W.R.)« less

Burst mode pumping: A new mechanism of drinking in mosquitoes

DOE PAGES

Kikuchi, Kenji; Stremler, Mark A.; Chatterjee, Souvick; ...

2018-03-20

Mosquitoes transport liquid foods into the body using two muscular pumps in the head. In normal drinking, these pumps reciprocate in a stereotyped pattern of oscillation, with a high frequency but small stroke volume. Do mosquitoes modulate their neuromotor programs for pumping to produce different drinking modes? More broadly, what are the mechanical consequences of a two-pump system in insects? To address these questions, we used synchrotron x-ray imaging and fluid mechanical modeling to investigate drinking performance in mosquitoes. X-ray imaging of the pumps during drinking revealed two modes of pumping: continuous reciprocation with multiple small strokes, and a newlymore » discovered ‘burst mode’ involving a single, large-volume stroke. Results from modeling demonstrate that burst mode pumping creates a very large pressure drop and high volume flow rate, but requires a massive increase in power, suggesting that continuous pumping is more economical for drinking. Modeling also demonstrates that, from one mode of pumping to the other, the mechanical role of the individual pumps changes. Furthermore, these results suggest that the advantage of a two-pump system in insects lies in its flexibility, enabling the animal to pump efficiently or powerfully as demanded by environmental considerations.« less

Burst mode pumping: A new mechanism of drinking in mosquitoes

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

Kikuchi, Kenji; Stremler, Mark A.; Chatterjee, Souvick

Mosquitoes transport liquid foods into the body using two muscular pumps in the head. In normal drinking, these pumps reciprocate in a stereotyped pattern of oscillation, with a high frequency but small stroke volume. Do mosquitoes modulate their neuromotor programs for pumping to produce different drinking modes? More broadly, what are the mechanical consequences of a two-pump system in insects? To address these questions, we used synchrotron x-ray imaging and fluid mechanical modeling to investigate drinking performance in mosquitoes. X-ray imaging of the pumps during drinking revealed two modes of pumping: continuous reciprocation with multiple small strokes, and a newlymore » discovered ‘burst mode’ involving a single, large-volume stroke. Results from modeling demonstrate that burst mode pumping creates a very large pressure drop and high volume flow rate, but requires a massive increase in power, suggesting that continuous pumping is more economical for drinking. Modeling also demonstrates that, from one mode of pumping to the other, the mechanical role of the individual pumps changes. Furthermore, these results suggest that the advantage of a two-pump system in insects lies in its flexibility, enabling the animal to pump efficiently or powerfully as demanded by environmental considerations.« less

ρ-VOF: An interface sharpening method for gas-liquid flow simulation

NASA Astrophysics Data System (ADS)

Wang, Jiantao; Liu, Gang; Jiang, Xiong; Mou, Bin

2018-05-01

The study on simulation of compressible gas-liquid flow remains open. Popular methods are either confined to incompressible flow regime, or inevitably induce smear of the free interface. A new finite volume method for compressible two-phase flow simulation is contributed for this subject. First, the “heterogeneous equilibrium” assumption is introduced to the control volume, by hiring free interface reconstruction technology, the distribution of each component in the control volume is achieved. Next, AUSM+-up (advection upstream splitting method) scheme is employed to calculate the convective fluxes and pressure fluxes, with the contact discontinuity characteristic considered, followed by the update of the whole flow field. The new method features on density-based pattern and interface reconstruction technology from VOF (volume of fluid), thus we name it “ρ-VOF method”. Inherited from AUSM families and VOF, ρ-VOF behaves as an all-speed method, capable of simulating shock in gas-liquid flow, and preserving the sharpness of the free interface. Gas-liquid shock tube is simulated to evaluate the method, from which good agreement is obtained between the predicted results and those of the cited literature, meanwhile, sharper free interface is identified. Finally, the capability and validity of ρ-VOF method can be concluded in compressible gas-liquid flow simulation.

Volume requirements for aerated mud drilling

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

Guo, B.; Rajtar, J.M.

1995-09-01

Aerated mud drilling has been recognized as having many advantages over conventional mud drilling, such ass higher penetration rate, less formation damage, minimized lost circulation, and lower drilling cost. In some areas, the use of aerated mud as a circulating medium for drilling oil and gas wells is becoming an attractive practice. Maintaining an optimum combination of liquid and air flow rates is important in aerated drilling operations. However, most drilling operators are unclear on what constitutes the ``optimum combination of the liquid and air flow rates.`` Guo et al. presented a mathematical approach to determining the flowing bottomhole pressuremore » (BHP) for aerated mud drilling. This paper addresses the use of Guo et al.`s mathematical model to determine liquid and air volume requirements considering wellbore stability, pipe sticking, and formation damage as well as the cuttings-carry capacity of the aerated mud. For a formation-damage-prevention point of view, the liquid fraction in the fluid stream should e as low as possible. However, a sufficient mud flow rate is always required to make the hole stable and to maintain the cuttings-carrying capacity of the aerated mud without injecting much air volume. This paper provides a simple approach to determining the liquid and air volume requirements for aerated mud drilling.« less

Controlled generation of large volumes of atmospheric clouds in a ground-based environmental chamber

NASA Technical Reports Server (NTRS)

Hettel, H. J.; Depena, R. G.; Pena, J. A.

1975-01-01

Atmospheric clouds were generated in a 23,000 cubic meter environmental chamber as the first step in a two part study on the effects of contaminants on cloud formation. The generation procedure was modeled on the terrestrial generation mechanism so that naturally occurring microphysics mechanisms were operative in the cloud generation process. Temperature, altitude, liquid water content, and convective updraft velocity could be selected independently over the range of terrestrially realizable clouds. To provide cloud stability, a cotton muslin cylinder 29.3 meters in diameter and 24.2 meters high was erected within the chamber and continuously wetted with water at precisely the same temperature as the cloud. The improved instrumentation which permitted fast, precise, and continual measurements of cloud temperature and liquid water content is described.

Contamination-Free Sonoreactor for the Food Industry

NASA Astrophysics Data System (ADS)

Dion, Jean-Luc

A new sonoreactor technology is presented here, which should open vast development possibilities in various fields of chemical, pharmaceutical, and food industries. It should give a decisive impulse to sonochemistry in these various areas. These exclusive systems use high-power converging acoustic waves in a tube to produce a relatively large volume confined acoustic cavitation zone in flowing liquid reagents. It is well known that numerous chemical reactions are strongly accelerated when they take place inside such a zone. The new cylindrical sonoreactors do not contaminate the processed liquids with erosion products as other devices do. The processing conditions can be widely varied with pressure, power, temperature, and flow rate. The processing capacity of the largest models may be up to several tons per hour, using an electric power input of about 50 kW.

Ultrathin zoom telescopic objective.

PubMed

Li, Lei; Wang, Di; Liu, Chao; Wang, Qiong-Hua

2016-08-08

We report an ultrathin zoom telescopic objective that can achieve continuous zoom change and has reduced compact volume. The objective consists of an annular folded lens and three electrowetting liquid lenses. The annular folded lens undertakes the main part of the focal power of the lens system. Due to a multiple-fold design, the optical path is folded in a lens with the thickness of ~1.98mm. The electrowetting liquid lenses constitute a zoom part. Based on the proposed objective, an ultrathin zoom telescopic camera is demonstrated. We analyze the properties of the proposed objective. The aperture of the proposed objective is ~15mm. The total length of the system is ~18mm with a tunable focal length ~48mm to ~65mm. Compared with the conventional zoom telescopic objective, the total length has been largely reduced.

Quantum-limited Terahertz detection without liquid cryogens

NASA Technical Reports Server (NTRS)

2005-01-01

Under this contract, we have successfully designed, fabricated and tested a revolutionary new type of detector for Terahertz (THz) radiation, the tunable antenna-coupled intersubband Terahertz (TACIT) detector. The lowest-noise THz detectors used in the astrophysics community require cooling to temperatures below 4K. This deep cryogenic requirement forces satellites launched for THz- observing missions to include either large volumes of liquid Helium, complex cryocoolers, or both. Cryogenic requirements thus add significantly to the cost, complexity and mass of satellites and limit the duration of their missions. It hence desirable to develop new detector technologies with less stringent cryogenic requirements. Such detectors will not only be important in space-based astrophysics, but also respond to a growing demand for THz technology for earth-based scientific and commercial applications.

Quantitative tomographic measurements of opaque multiphase flows

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

GEORGE,DARIN L.; TORCZYNSKI,JOHN R.; SHOLLENBERGER,KIM ANN

2000-03-01

An electrical-impedance tomography (EIT) system has been developed for quantitative measurements of radial phase distribution profiles in two-phase and three-phase vertical column flows. The EIT system is described along with the computer algorithm used for reconstructing phase volume fraction profiles. EIT measurements were validated by comparison with a gamma-densitometry tomography (GDT) system. The EIT system was used to accurately measure average solid volume fractions up to 0.05 in solid-liquid flows, and radial gas volume fraction profiles in gas-liquid flows with gas volume fractions up to 0.15. In both flows, average phase volume fractions and radial volume fraction profiles from GDTmore » and EIT were in good agreement. A minor modification to the formula used to relate conductivity data to phase volume fractions was found to improve agreement between the methods. GDT and EIT were then applied together to simultaneously measure the solid, liquid, and gas radial distributions within several vertical three-phase flows. For average solid volume fractions up to 0.30, the gas distribution for each gas flow rate was approximately independent of the amount of solids in the column. Measurements made with this EIT system demonstrate that EIT may be used successfully for noninvasive, quantitative measurements of dispersed multiphase flows.« less

Rapid Crystallization of the Bishop Magma

NASA Astrophysics Data System (ADS)

Gualda, G. A.; Anderson, A. T.; Sutton, S. R.

2007-12-01

Substantial effort has been made to understand the longevity of rhyolitic magmas, and particular attention has been paid to the systems in the Long Valley area (California). Recent geochronological data suggest discrete magma bodies that existed for hundreds of thousands of years. Zircon crystallization ages for the Bishop Tuff span 100-200 ka, and were interpreted to reflect slow crystallization of a liquid-rich magma. Here we use the diffusional relaxation of Ti zoning in quartz to investigate the longevity of the Bishop magma. We have used such an approach to show the short timescales of crystallization of Ti-rich rims on quartz from early- erupted Bishop Tuff. We have now recognized Ti-rich cores in quartz that can be used to derive the timescales of their crystallization. We studied four samples of the early-erupted Bishop. Hand-picked crystals were mounted on glass slides and polished. Cathodoluminescence (CL) images were obtained using the electron microprobe at the University of Chicago. Ti zoning was documented using the GeoSoilEnviroCARS x-ray microprobe at the Advanced Photon Source (Argonne National Lab). Quartz crystals in all 4 samples include up to 3 Ti-bearing zones: a central core (50-100 μm in diameter, ca. 50 ppm Ti), a volumetrically predominant interior (~40 ppm Ti), and in some crystals a 50-100 μm thick rim (50 ppm Ti). Maximum estimates of core residence times were calculated using a 1D diffusion model, as the time needed to smooth an infinitely steep profile to fit the observed profile. Surprisingly, even for the largest crystals studied - ca. 2 mm in diameter - core residence times are less than 1 ka. Calculated growth rates imply that even cm-sized crystals crystallized in less than 10 ka. Crystal size distribution data show that crystals larger than 3 mm are exceedingly rare, such that the important inference is that the bulk of the crystallization of the early-erupted Bishop magma occurred in only a few thousand years. This timescale is 2 orders of magnitude smaller than the shortest durations derived from geochronology. In the current paradigm, this implies that the Bishop magma existed virtually free of crystals for 100-200 ka. Occasional recharge of the system could cause resorption of crystals. The challenge, however, is to explain how a large- volume, liquid- and volatile-rich system, was prevented from erupting for over 100 ka. The trouble is such that it puts into question the whole concept of a long-lived, liquid-rich magma body. Evidence has accumulated to show that the Bishop magma was stratified and did not convect during crystallization, the stratification was established prior to phenocryst crystallization, and crystal migration did not significantly perturb the stratification. All these are simpler to explain if liquid-rich magma only existed for a short period of time, and we estimate the time as being on the order of 1 ka. The geospeedometric timescale inferred can be reconciled with the geochronological evidence if we interpret zircon crystallization ages as reflecting episodic growth in response to waxing and waning of a mushy body, rather than continuous crystallization from liquid-rich magma in a long-lived, large-volume magma body. We speculate that only after 100-200 ka did favorable conditions emerge and allowed for the generation of a large volume of liquid-rich magma. Once such a body of magma was established, it progressed rather quickly towards eruption.

Rapid analysis of aflatoxins B1, B2, and ochratoxin A in rice samples using dispersive liquid-liquid microextraction combined with HPLC.

PubMed

Lai, Xian-Wen; Sun, Dai-Li; Ruan, Chun-Qiang; Zhang, He; Liu, Cheng-Lan

2014-01-01

A novel, simple, and rapid method is presented for the analysis of aflatoxin B1, aflatoxin B2, and ochratoxin A in rice samples by dispersive liquid-liquid microextraction combined with LC and fluorescence detection. After extraction of the rice samples with a mixture of acetonitrile/water/acetic acid, mycotoxins were rapidly partitioned into a small volume of organic solvent (chloroform) by dispersive liquid-liquid microextraction. The three mycotoxins were simultaneously determined by LC with fluorescence detection after precolumn derivatization for aflatoxin B1 and B2. Parameters affecting both extraction and dispersive liquid-liquid microextraction procedures, including the extraction solvent, the type and volume of extractant, the volume of dispersive solvent, the addition of salt, the pH and the extraction time, were optimized. The optimized protocol provided an enrichment factor of approximately 1.25 and with detection of limits (0.06-0.5 μg/kg) below the maximum levels imposed by current regulations for aflatoxins and ochratoxin A. The mean recovery of three mycotoxins ranged from 82.9-112%, with a RSD less than 7.9% in all cases. The method was successfully applied to measure mycotoxins in commercial rice samples collected from local supermarkets in China. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Constraints on both the quadratic and quartic symmetry energy coefficients by 2β --decay energies

NASA Astrophysics Data System (ADS)

Wan, Niu; Xu, Chang; Ren, Zhongzhou; Liu, Jie

2018-05-01

In this Rapid Communication, the 2 β- -decay energies Q (2 β-) given in the atomic mass evaluation are used to extract not only the quadratic volume symmetry energy coefficient csymv, but also the quartic one csym,4 v. Based on the modified Bethe-Weizsäcker nuclear mass formula of the liquid-drop model, the decay energy Q (2 β-) is found to be closely related to both the quadratic and quartic symmetry energy coefficients csymv and csym,4 v. There are totally 449 data of decay energies Q (2 β-) used in the present analysis where the candidate nuclei are carefully chosen by fulfilling the following criteria: (1) large neutron-proton number difference N -Z , (2) large isospin asymmetry I , and (3) limited shell effect. The values of csymv and csym,4 v are extracted to be 29.345 and 3.634 MeV, respectively. Moreover, the quadratic surface-volume symmetry energy coefficient ratio is determined to be κ =csyms/csymv=1.356 .

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

Furuta, H.; Imura, A.; Furuta, Y.

Recently, technique of Gadolinium loaded liquid scintillator (Gd-LS) for reactor neutrino oscillation experiments has attracted attention as a monitor of reactor operation and 'nuclear Gain (GA)' for IAEA safeguards. For the practical use, R and D of the 1 ton class compact detector, which is measurable above ground, is necessary. Especially, it is important to reduce much amount of fast neutron background induced by cosmic muons with data analysis for the measurement above ground. We developed a prototype of the Gd-LS detector with 200 L of the target volume, which has Pulse Shape Discrimination (PSD) ability for the fast neutronmore » reduction with data analysis. Usually, it is well known that it is difficult to keep high fast neutron reduction power of PSD with the large volume size such as the neutrino reactor monitor. We evaluated the PSD ability of our prototype with real fast neutrons induced by the muons in our laboratory above ground, and we could confirm to keep the high fast neutron reduction power with even our large detector size. (authors)« less

Automated gas chromatography

DOEpatents

Mowry, C.D.; Blair, D.S.; Rodacy, P.J.; Reber, S.D.

1999-07-13

An apparatus and process for the continuous, near real-time monitoring of low-level concentrations of organic compounds in a liquid, and, more particularly, a water stream. A small liquid volume of flow from a liquid process stream containing organic compounds is diverted by an automated process to a heated vaporization capillary where the liquid volume is vaporized to a gas that flows to an automated gas chromatograph separation column to chromatographically separate the organic compounds. Organic compounds are detected and the information transmitted to a control system for use in process control. Concentrations of organic compounds less than one part per million are detected in less than one minute. 7 figs.

Controllable picoliter pipetting using hydrophobic microfluidic valves

NASA Astrophysics Data System (ADS)

Zhang, M.; Huang, J.; Qian, X.; Mi, S.; Wang, X.

2017-06-01

A picoliter pipetting technique using the microfluidic method is presented. Utilizing the hydrophobic self-assembled monolayer films patterned in microchannels as pressure-controlled valves, a small volume of liquid can be separated by a designed channel trap and then ejected from the channel end at a higher pressure. The liquid trap section is composed of a T-shaped channel junction and a hydrophobic patch. The liquid volume can be precisely controlled by varying the distance of the hydrophobic patch from the T-junction. By this means, liquid less than 100 pl can be separated and pipetted. The developed device is potentially useful for sample dispensing in biological, medical, and chemical applications.

Automated gas chromatography

DOEpatents

Mowry, Curtis D.; Blair, Dianna S.; Rodacy, Philip J.; Reber, Stephen D.

1999-01-01

An apparatus and process for the continuous, near real-time monitoring of low-level concentrations of organic compounds in a liquid, and, more particularly, a water stream. A small liquid volume of flow from a liquid process stream containing organic compounds is diverted by an automated process to a heated vaporization capillary where the liquid volume is vaporized to a gas that flows to an automated gas chromatograph separation column to chromatographically separate the organic compounds. Organic compounds are detected and the information transmitted to a control system for use in process control. Concentrations of organic compounds less than one part per million are detected in less than one minute.

40 CFR 761.1 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-07-01

... concentrations shall be determined on a weight-per-weight basis (e.g., milligrams per kilogram), or for liquids, on a weight-per-volume basis (e.g., milligrams per liter) if the density of the liquid is also... µg/100 cm2. (4) PCBs can be found in liquid, non-liquid and multi-phasic (combinations of liquid and...

On the existence of vapor-liquid phase transition in dusty plasmas

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

Kundu, M.; Sen, A.; Ganesh, R.

2014-10-15

The phenomenon of phase transition in a dusty-plasma system (DPS) has attracted some attention in the past. Earlier Farouki and Hamaguchi [J. Chem. Phys. 101, 9876 (1994)] have demonstrated the existence of a liquid to solid transition in DPS where the dust particles interact through a Yukawa potential. However, the question of the existence of a vapor-liquid (VL) transition in such a system remains unanswered and relatively unexplored so far. We have investigated this problem by performing extensive molecular dynamics simulations which show that the VL transition does not have a critical curve in the pressure versus volume diagram formore » a large range of the Yukawa screening parameter κ and the Coulomb coupling parameter Γ. Thus, the VL phase transition is found to be super-critical, meaning that this transition is continuous in the dusty plasma model given by Farouki and Hamaguchi. We provide an approximate analytic explanation of this finding by means of a simple model calculation.« less

Microgravity fluid management requirements of advanced solar dynamic power systems

NASA Technical Reports Server (NTRS)

Migra, Robert P.

1987-01-01

The advanced solar dynamic system (ASDS) program is aimed at developing the technology for highly efficient, lightweight space power systems. The approach is to evaluate Stirling, Brayton and liquid metal Rankine power conversion systems (PCS) over the temperature range of 1025 to 1400K, identify the critical technologies and develop these technologies. Microgravity fluid management technology is required in several areas of this program, namely, thermal energy storage (TES), heat pipe applications and liquid metal, two phase flow Rankine systems. Utilization of the heat of fusion of phase change materials offers potential for smaller, lighter TES systems. The candidate TES materials exhibit large volume change with the phase change. The heat pipe is an energy dense heat transfer device. A high temperature application may transfer heat from the solar receiver to the PCS working fluid and/or TES. A low temperature application may transfer waste heat from the PCS to the radiator. The liquid metal Rankine PCS requires management of the boiling/condensing process typical of two phase flow systems.

Liquid volume measurement method for the picoliter to nanoliter volume range based on quartz crystal microbalance technology

NASA Astrophysics Data System (ADS)

Liang, Dong; Zhang, Jin; Thanikhatla Govindaiah, Muniyogeshbabu; Tanguy, Laurent; Ernst, Andreas; Zengerle, Roland; Koltay, Peter

2014-09-01

In this article, a quantitative liquid volume measurement method for the sub-nanoliter range using a quartz crystal microbalance (QCM) is described and experimentally analyzed. The primary measurement device to determine the volume of small liquid droplets is a QCM sensor coated with a surface-attached hydrogel to improve the mechanical coupling of the liquid to the sensor surface. An experimental evaluation of measured volumes in the range of 3 nl to 15 nl in normal room conditions has been performed with three identical sensors prepared with a PDMAA-1%MaBP hydrogel coating with a thickness of 1.5 µm ± 0.12 µm. A linearity of R2 more than 0.87, an average coefficient of variation (CV) within one experimental run of 5.7%, a mean absolute relative bias of 5.5%, and a sensor-to-sensor variation of 6.3% have been experimentally determined. The feasibility of this method has also been experimentally proven for the picoliter volume range down to 200 pl, with an average CV of 5.3% and a mean absolute relative bias of 6.5%. Furthermore, a stability evaluation consisting of 10 experimental series with approximately 150 measurements over the course of one week has been performed. This evaluation showed that the experimental setup, although exhibiting highly consistent performance within one measurement run, is not yet reproducible enough for long-term and repeated use because of undefined swelling and crack formation in the hydrogel layer. The low reproducibility implies a relatively high expanded uncertainty, with k = 2 according to the JCGM ‘Evaluation of Measurement Data—Guide to the Expression of Uncertainty in Measurement’ (GUM) for the total measurement method of approximately 3.82 nl when measuring a 10 nl liquid droplet. Nevertheless, the QCM method as described here contributes to significant progress beyond the state-of-the-art that might allow new opportunities for precise measurement of sub-nanoliter liquid volumes.

Foaming volume and foam stability

NASA Technical Reports Server (NTRS)

Ross, Sydney

1947-01-01

A method of measuring foaming volume is described and investigated to establish the critical factors in its operation. Data on foaming volumes and foam stabilities are given for a series of hydrocarbons and for a range of concentrations of aqueous ethylene-glycol solutions. It is shown that the amount of foam formed depends on the machinery of its production as well as on properties of the liquid, whereas the stability of the foam produced, within specified mechanical limitations, is primarily a function of the liquid.

Liquid scintillation sample analysis in microcentrifuge tubes.

PubMed

Elliott, J C

1993-01-01

Local regulations prohibiting drain disposal of "biodegradable" liquid scintillation cocktails prompted investigation of volume reduction for these materials. Microcentrifuge tubes were used with aqueous and filter media samples of 3H, 14C, 32P, and 125I. Backgrounds, counting efficiencies, figures of merit, and spectral distributions obtained for microcentrifuge tubes compared favorably to conventional vials. Differences in 32P spectra for solid support samples appeared related to filter material and sample volume. Decreases in sample costs and waste volume and disposal costs were approximately 50-75%.

Wetting and elasto-plasticity based sculpture of liquid marbles.

PubMed

Liu, Jianlin; Zuo, Pingcheng

2016-02-01

As an emerging material with exotic properties, liquid marble holds great potential for such areas as microfluidics, stimuli-responsive sensors, micro-chemical reactors, micro-bioreactors, energy harvesting devices, and mechanical structures. In this study, we mainly concentrate on the mechanical behaviors, such as elasto-plasticity of liquid marble with the decrease of liquid volume. The contact radius with the substrate and Young's contact angle of liquid marble are both measured with the change of water volume, and those of a water droplet are compared. The mechanism for the different responses for liquid marble and water droplet is clarified according to the mechanics analysis. Moreover, it is found that liquid marble can behave like an elasto-plastic material when the particle surface density is big enough. Based upon this fact, liquid marble can be sculpted to all kinds of special shapes as expected. These investigations may cast new light on how to engineer multifunctional materials and devices, which are beneficial to microprinting and micromachining.

The effect of changing the contact surface area between pleural liquid and pleura on the turnover of pleural liquid.

PubMed

Nakamura, T; Hara, H; Ijima, F; Arai, T; Kira, S

1984-03-01

To study the dynamics of pleural liquid, 250 ml of saline labeled with markers were injected into the pleural cavity of anesthetized dogs. For 3 h, liquid volume and concentration of these markers were measured. In a control group of dogs, the turnover rate of pleural liquid was 19.6 +/- 5.6 ml/min and lymphatic flow was 0.58 +/- 0.07 ml/min. In a group of pneumonectomized dogs, the turnover rate and lymphatic flow fell to about one fourth of those in the control group. When the left pulmonary artery was occluded, the turnover rate was halved, but lymphatic flow was not significantly different from that in the control group. These results suggest that the turnover rate of pleural liquid is dependent on the area of contact between pleural liquid and pleura and on the blood flow of the pleura. In addition, it appears that changes in pleural liquid volume are dependent on lymphatic flow.

Field lens multiplexing in holographic 3D displays by using Bragg diffraction based volume gratings

NASA Astrophysics Data System (ADS)

Fütterer, G.

2016-11-01

Applications, which can profit from holographic 3D displays, are the visualization of 3D data, computer-integrated manufacturing, 3D teleconferencing and mobile infotainment. However, one problem of holographic 3D displays, which are e.g. based on space bandwidth limited reconstruction of wave segments, is to realize a small form factor. Another problem is to provide a reasonable large volume for the user placement, which means to provide an acceptable freedom of movement. Both problems should be solved without decreasing the image quality of virtual and real object points, which are generated within the 3D display volume. A diffractive optical design using thick hologram gratings, which can be referred to as Bragg diffraction based volume gratings, can provide a small form factor and high definition natural viewing experience of 3D objects. A large collimated wave can be provided by an anamorphic backlight unit. The complex valued spatial light modulator add local curvatures to the wave field he is illuminated with. The modulated wave field is focused onto to the user plane by using a volume grating based field lens. Active type liquid crystal gratings provide 1D fine tracking of approximately +/- 8° deg. Diffractive multiplex has to be implemented for each color and for a set of focus functions providing coarse tracking. Boundary conditions of the diffractive multiplexing are explained. This is done in regards to the display layout and by using the coupled wave theory (CWT). Aspects of diffractive cross talk and its suppression will be discussed including longitudinal apodized volume gratings.

Glass Transition Temperature and Density Scaling in Cumene at Very High Pressure.

PubMed

Ransom, T C; Oliver, W F

2017-07-14

We present a new method that allows direct measurements of the glass transition temperature T_{g} at pressures up to 4.55 GPa in the glass-forming liquid cumene (isopropylbenzene). This new method uses a diamond anvil cell and can measure T_{g} at pressures of 10 GPa or greater. Measuring T_{g} at the glass→liquid transition involves monitoring the disappearance of pressure gradients initially present in the glass, but also takes advantage of the large increase in the volume expansion coefficient α_{p} at T_{g} as the supercooled or superpressed liquid is entered. Accurate T_{g}(P) values in cumene allow us to show that density scaling holds along this isochronous line up to pressures much higher than any previous study, corresponding to a density increase of 29%. Our results for cumene over this huge compression range yield ρ^{γ}/T=C, where C is a constant and where γ=4.77±0.02 for this nonassociated glass-forming system. Finally, high-pressure cumene viscosity data from the literature taken at much lower pressures and at several different temperatures, corresponding to a large dynamic range of nearly 13 orders of magnitude, are shown to superimpose on a plot of η vs ρ^{γ}/T for the same value of γ.

Market trends in the projection display industry

NASA Astrophysics Data System (ADS)

Dash, Sweta

2001-03-01

The projection display industry represents a multibillion- dollar market that includes four distinct technologies. High-volume consumer products and high-value business products drive the market, with different technologies being used in different application markets. The consumer market is dominated by rear CRT technology, especially in the projection TV segment. Rear LCD (liquid crystal display), MEMS/DLP (or Digital Light Processing TM) and LCOS (Liquid-crystal-on-silicon) TVs are slowly emerging as future competitors to rear CRT projectors. Front CRT projectors are also facing challenges from LCD and DLP technology for the home theater market while the business market is completely dominated by front LCD and DLP technology. Three-chip DLP projectors have replaced liquid crystal light valves in large venue applications where projectors have higher light output requirements. In recent years front LCD and LCOS projectors have been increasingly competing with 3-chip DLP projectors especially at the low end of the large venue application market. Within the next five years the projection market will experience very fast growth. Sales and presentation applications, which are the fastest growing applications in the business market, will continue to be the major driving force for the growth for front projectors, and the shift in the consumer market to digital and HDTV products will drive the rear projection market.

Transfer of thermal microwaves in the atmosphere, volume 1

NASA Technical Reports Server (NTRS)

Paris, J. F.

1971-01-01

The Mie theory is used to determine the absorption and scattering properties of liquid hydrometeors at 27 microwave frequencies from 500 MHz to 60 GHz. Based on the Marshall-Palmer distribution of drop sizes, regression equations are developed for the volume absorption coefficient of rain as a function of its temperature and content of liquid water.

Strong ion exchange in centrifugal partition extraction (SIX-CPE): effect of partition cell design and dimensions on purification process efficiency.

PubMed

Hamzaoui, Mahmoud; Hubert, Jane; Reynaud, Romain; Marchal, Luc; Foucault, Alain; Renault, Jean-Hugues

2012-07-20

The aim of this article was to evaluate the influence of the column design of a hydrostatic support-free liquid-liquid chromatography device on the process efficiency when the strong ion-exchange (SIX) development mode is used. The purification of p-hydroxybenzylglucosinolate (sinalbin) from a crude aqueous extract of white mustard seeds (Sinapis alba L.) was achieved on two types of devices: a centrifugal partition chromatograph (CPC) and a centrifugal partition extractor (CPE). They differ in the number, volume and geometry of their partition cells. The SIX-CPE process was evaluated in terms of productivity and sinalbin purification capability as compared to previously optimized SIX-CPC protocols that were carried out on columns of 200 mL and 5700 mL inner volume, respectively. The objective was to determine whether the decrease in partition cell number, the increase in their volume and the use of a "twin cell" design would induce a significant increase in productivity by applying higher mobile phase flow rate while maintaining a constant separation quality. 4.6g of sinalbin (92% recovery) were isolated from 25 g of a crude white mustard seed extract, in only 32 min and with a purity of 94.7%, thus corresponding to a productivity of 28 g per hour and per liter of column volume (g/h/LV(c)). Therefore, the SIX-CPE process demonstrates promising industrial technology transfer perspectives for the large-scale isolation of ionized natural products. Copyright © 2012 Elsevier B.V. All rights reserved.

Investigation of Possible Maillard Reaction Between Acyclovir and Dextrose upon Dilution Prior to Parenteral Administration.

PubMed

Siahi Shadbad, Mohammad Reza; Ghaderi, Faranak; Hatami, Leila; Monajjemzadeh, Farnaz

2016-12-01

In this study the stability of parenteral acyclovir (ACV) when diluted in dextrose (DEX) as large volume intravenous fluid preparation (LVIF) was evaluated and the possible Maillard reaction adducts were monitored in the recommended infusion time. Different physicochemical methods were used to evaluate the Maillard reaction of dextrose with ACV to track the reaction in real infusion condition. Other large volume intravenous fluids were checked regarding the diluted drug stability profile. Differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and mass data proved the reaction of glucose with dextrose. A Maillard-specific high performance liquid chromatography (HPLC) method was used to track the reaction in real infusion condition in vitro. The nucleophilic reaction occurred in diluted parenteral preparations of acyclovir in 5% dextrose solutions. The best diluent solution was also selected as sodium chloride and introduced based on drug stability and also its adsorption onto different infusion sets (PVC or non PVC) to provide an acceptable administration protocol in clinical practices. Although, the Maillard reaction was proved and successfully tracked in diluted solutions, and the level of drug loss when diluted in dextrose was reported to be between 0.27 up to 1.03% of the initial content. There was no drug adsorption to common infusion sets. The best diluent for parenteral acyclovir is sodium chloride large volume intravenous fluid.

Glass Transition Temperature of Saccharide Aqueous Solutions Estimated with the Free Volume/Percolation Model.

PubMed

Constantin, Julian Gelman; Schneider, Matthias; Corti, Horacio R

2016-06-09

The glass transition temperature of trehalose, sucrose, glucose, and fructose aqueous solutions has been predicted as a function of the water content by using the free volume/percolation model (FVPM). This model only requires the molar volume of water in the liquid and supercooled regimes, the molar volumes of the hypothetical pure liquid sugars at temperatures below their pure glass transition temperatures, and the molar volumes of the mixtures at the glass transition temperature. The model is simplified by assuming that the excess thermal expansion coefficient is negligible for saccharide-water mixtures, and this ideal FVPM becomes identical to the Gordon-Taylor model. It was found that the behavior of the water molar volume in trehalose-water mixtures at low temperatures can be obtained by assuming that the FVPM holds for this mixture. The temperature dependence of the water molar volume in the supercooled region of interest seems to be compatible with the recent hypothesis on the existence of two structure of liquid water, being the high density liquid water the state of water in the sugar solutions. The idealized FVPM describes the measured glass transition temperature of sucrose, glucose, and fructose aqueous solutions, with much better accuracy than both the Gordon-Taylor model based on an empirical kGT constant dependent on the saccharide glass transition temperature and the Couchman-Karasz model using experimental heat capacity changes of the components at the glass transition temperature. Thus, FVPM seems to be an excellent tool to predict the glass transition temperature of other aqueous saccharides and polyols solutions by resorting to volumetric information easily available.

Effect of particle- and specimen-level transport on product state in compacted-powder combustion synthesis and thermal debinding of polymers from molded powders

NASA Astrophysics Data System (ADS)

Oliveira, Amir Antonio Martins

The existence of large gradients within particles and fast temporal variations in the temperature and species concentration prevents the use of asymptotic approximations for the closure of the volume-averaged, specimen-level formulations. In this case a solution of the particle-level transport problem is needed to complement the specimen-level volume-averaged equations. Here, the use of combined specimen-level and particle-level models for transport in reactive porous media is demonstrated with two examples. For the gasless compacted-powder combustion synthesis, a three-scale model is developed. The specimen-level model is based on the volume-averaged equations for species and temperature. Local thermal equilibrium is assumed and the macroscopic mass diffusion and convection fluxes are neglected. The particle-level model accounts for the interparticle diffusion (i.e., the liquid migration from liquid-rich to liquid-lean regions) and the intraparticle diffusion (i.e., the species mass diffusion within the product layer formed at the surface of the high melting temperature component). It is found that the interparticle diffusion controls the extent of conversion to the final product, the maximum temperature, and to a smaller degree the propagation velocity. The intraparticle diffusion controls the propagation velocity and to a smaller degree the maximum temperature. The initial stages of thermal degradation of EVA from molded specimens is modeled using volume-averaged equations for the species and empirical models for the kinetics of the thermal degradation, the vapor-liquid equilibrium, and the diffusion coefficient of acetic acid in the molten polymer. It is assumed that a bubble forms when the partial pressure of acetic acid exceeds the external ambient pressure. It is found that the removal of acetic acid is characterized by two regimes, a pre-charge dominated regime and a generation dominated regime. For the development of an optimum debinding schedule, the heating rate is modulated to avoid bubbling, while the concentration and temperature follow the bubble-point line for the mixture. The results show a strong dependence on the presence of a pre-charge. It is shown that isolation of the pre-charge effect by using temporary lower heating rates results in an optimum schedule for which the process time is reduced by over 70% when compared to a constant heating rate schedule.

Manufactured caverns in carbonate rock

DOEpatents

Bruce, David A.; Falta, Ronald W.; Castle, James W.; Murdoch, Lawrence C.

2007-01-02

Disclosed is a process for manufacturing underground caverns suitable in one embodiment for storage of large volumes of gaseous or liquid materials. The method is an acid dissolution process that can be utilized to form caverns in carbonate rock formations. The caverns can be used to store large quantities of materials near transportation facilities or destination markets. The caverns can be used for storage of materials including fossil fuels, such as natural gas, refined products formed from fossil fuels, or waste materials, such as hazardous waste materials. The caverns can also be utilized for applications involving human access such as recreation or research. The method can also be utilized to form calcium chloride as a by-product of the cavern formation process.

An aggregation-volume-bias Monte Carlo investigation on the condensation of a Lennard-Jones vapor below the triple point and crystal nucleation in cluster systems: an in-depth evaluation of the classical nucleation theory.

PubMed

Chen, Bin; Kim, Hyunmi; Keasler, Samuel J; Nellas, Ricky B

2008-04-03

The aggregation-volume-bias Monte Carlo based simulation technique, which has led to our recent success in vapor-liquid nucleation research, was extended to the study of crystal nucleation processes. In contrast to conventional bulk-phase techniques, this method deals with crystal nucleation events in cluster systems. This approach was applied to the crystal nucleation of Lennard-Jonesium under a wide range of undercooling conditions from 35% to 13% below the triple point. It was found that crystal nucleation in these model clusters proceeds initially via a vapor-liquid like aggregation followed by the formation of crystals inside the aggregates. The separation of these two stages of nucleation is distinct except at deeper undercooling conditions where the crystal nucleation barrier was found to diminish. The simulation results obtained for these two nucleation steps are separately compared to the classical nucleation theory (CNT). For the vapor-liquid nucleation step, the CNT was shown to provide a reasonable description of the critical cluster size but overestimate the barrier heights, consistent with previous simulation studies. On the contrary, for the crystal nucleation step, nearly perfect agreement with the barrier heights was found between the simulations and the CNT. For the critical cluster size, the comparison is more difficult as the simulation data were found to be sensitive to the definition of the solid cluster, but a stringent criterion and lower undercooling conditions generally lead to results closer with the CNT. Additional simulations at undercooling conditions of 40% or above indicate a nearly barrierless transition from the liquid to crystalline-like structure for sufficiently large clusters, which leads to further departure of the barrier height predicted by the CNT from the simulation data for the aggregation step. This is consistent with the latest experimental results on argon that show an unusually large underestimation of the nucleation rate by the CNT toward deep undercooling conditions.

Measuring liquid density using Archimedes' principle

NASA Astrophysics Data System (ADS)

Hughes, Stephen W.

2006-09-01

A simple technique is described for measuring absolute and relative liquid density based on Archimedes' principle. The technique involves placing a container of the liquid under test on an electronic balance and suspending a probe (e.g. a glass marble) attached to a length of line beneath the surface of the liquid. If the volume of the probe is known, the density of liquid is given by the difference between the balance reading before and after immersion of the probe divided by the volume of the probe. A test showed that the density of water at room temperature could be measured to an accuracy and precision of 0.01 ± 0.1%. The probe technique was also used to measure the relative density of milk, Coca-Cola, fruit juice, olive oil and vinegar.

Finite element solution of low bond number sloshing

NASA Technical Reports Server (NTRS)

Wohlen, R. L.; Park, A. C.; Warner, D. M.

1975-01-01

The dynamics of liquid propellant in a low Bond number environment which are critical to the design of spacecraft systems with respect to orbital propellant transfer and attitude control system were investigated. Digital computer programs were developed for the determination of liquid free surface equilibrium shape, lateral slosh natural vibration mode shapes, and frequencies for a liquid in a container of arbitrary axisymmetric shape with surface tension forces the same order of magnitude as acceleration forces. A finite volume element representation of the liquid was used for the vibration analysis. The liquid free surface equilibrium shapes were computed for several tanks at various contact angles and ullage volumes. A configuration was selected for vibration analysis and lateral slosh mode shapes and natural frequencies were obtained. Results are documented.

Liquid oxygen/liquid hydrogen boost/vane pump for the advanced orbit transfer vehicles auxiliary propulsion system

NASA Technical Reports Server (NTRS)

Gluzek, F.; Mokadam, R. G.; To, I. H.; Stanitz, J. D.; Wollschlager, J.

1979-01-01

A rotating, positive displacement vane pump with an integral boost stage was designed to pump saturated liquid oxygen and liquid hydrogen for auxiliary propulsion system of orbit transfer vehicle. This unit is designed to ingest 10% vapor by volume, contamination free liquid oxygen and liquid hydrogen. The final pump configuration and the predicted performance are included.

Partial Molar Volumes of Aqua Ions from First Principles.

PubMed

Wiktor, Julia; Bruneval, Fabien; Pasquarello, Alfredo

2017-08-08

Partial molar volumes of ions in water solution are calculated through pressures obtained from ab initio molecular dynamics simulations. The correct definition of pressure in charged systems subject to periodic boundary conditions requires access to the variation of the electrostatic potential upon a change of volume. We develop a scheme for calculating such a variation in liquid systems by setting up an interface between regions of different density. This also allows us to determine the absolute deformation potentials for the band edges of liquid water. With the properly defined pressures, we obtain partial molar volumes of a series of aqua ions in very good agreement with experimental values.

Qualitative Observations Concerning Packing Densities for Liquids, Solutions, and Random Assemblies of Spheres

ERIC Educational Resources Information Center

Duer, W. C.; And Others

1977-01-01

Discusses comparisons of packing densities derived from known molar volume data of liquids and solutions. Suggests further studies for using assemblies of spheres as models for simple liquids and solutions. (MLH)

Quasi-steady vortical structures in vertically vibrating soap films

NASA Astrophysics Data System (ADS)

Vega, José M.; Higuera, F. J.; Weidman, P. D.

1998-10-01

An analysis of the quasi-steady streaming of the liquid in a vertically vibrated horizontal soap film is reported. The air around the soap film is seen to play a variety of roles: it transmits normal and tangential oscillatory stresses to the film, damps out Marangoni waves, and forces non-oscillatory deflection of the film and tangential motion of the liquid. Non-oscillatory volume forcing originating inside the liquid is also analysed. This forcing dominates the quasi-steady streaming when the excitation frequency is close to the eigenfrequency of a Marangoni mode of the soap film, while both volume forcing in the liquid and surface forcing of the gas on the liquid are important when no Marangoni mode resonates. Different manners by which the combined forcings can induce quasi-steady streaming motion are discussed and some numerical simulations of the quasi-steady liquid flow are presented.

Wetting morphologies on randomly oriented fibers.

PubMed

Sauret, Alban; Boulogne, François; Soh, Beatrice; Dressaire, Emilie; Stone, Howard A

2015-06-01

We characterize the different morphologies adopted by a drop of liquid placed on two randomly oriented fibers, which is a first step toward understanding the wetting of fibrous networks. The present work reviews previous modeling for parallel and touching crossed fibers and extends it to an arbitrary orientation of the fibers characterized by the tilting angle and the minimum spacing distance. Depending on the volume of liquid, the spacing distance between fibers and the angle between the fibers, we highlight that the liquid can adopt three different equilibrium morphologies: 1) a column morphology in which the liquid spreads between the fibers, 2) a mixed morphology where a drop grows at one end of the column or 3) a single drop located at the node. We capture the different morphologies observed using an analytical model that predicts the equilibrium configuration of the liquid based on the geometry of the fibers and the volume of liquid.

Theoretical and Experimental Investigations of the Process of Vibration Treatment of Liquid Metals Containing Nanoparticles

NASA Astrophysics Data System (ADS)

Vorozhtsov, S.; Kudryashova, O.; Promakhov, V.; Dammer, V.; Vorozhtsov, A.

2016-12-01

It is known that the use of external effects, such as acoustic fields (from ultrasonic to low-frequency range), help in breaking down agglomerates, improving particle wettability, providing uniform particle distribution in the melt volume, and reducing the grain size. The fragmentation of growing crystals, de-agglomeration of particles and their mixing in liquid metal under the influence of vibration (with frequencies of 10-100 Hz) are considered in this paper. The major advantage of such a technique in comparison with high-frequency methods (sonic, ultrasonic) is the capability of processing large melt volumes proportional to the wavelength. The mechanisms of the breaking down of particle agglomerates and the mixing of particles under conditions of cavitation and turbulence during the vibration treatment of the melt are considered. Expressions linking the threshold intensity and frequency with the amplitude necessary to activate mechanisms of turbulence and cavitation were obtained. The results of vibration treatment experiments for an aluminum alloy containing diamond nanoparticles are given. This treatment makes it possible to significantly reduce the grain size and to improve the casting homogeneity and thus improve the mechanical properties of the alloy.

Lab-on-a-Chip Based Protein Crystallization

NASA Technical Reports Server (NTRS)

vanderWoerd, Mark J.; Brasseur, Michael M.; Spearing, Scott F.; Whitaker, Ann F. (Technical Monitor)

2001-01-01

We are developing a novel technique with which we will grow protein crystals in very small volumes, utilizing chip-based, microfluidic ("LabChip") technology. This development, which is a collaborative effort between NASA's Marshall Space Flight Center and Caliper Technologies Corporation, promises a breakthrough in the field of protein crystal growth. Our initial results obtained from two model proteins, Lysozyme and Thaumatin, show that it is feasible to dispense and adequately mix protein and precipitant solutions on a nano-liter scale. The mixtures have shown crystal growth in volumes in the range of 10 nanoliters to 5 microliters. In addition, large diffraction quality crystals were obtained by this method. X-ray data from these crystals were shown to be of excellent quality. Our future efforts will include the further development of protein crystal growth with LabChip(trademark) technology for more complex systems. We will initially address the batch growth method, followed by the vapor diffusion method and the liquid-liquid diffusion method. The culmination of these chip developments is to lead to an on orbit protein crystallization facility on the International Space Station. Structural biologists will be invited to utilize the on orbit Iterative Biological Crystallization facility to grow high quality macromolecular crystals in microgravity.

Bubble formation in water with addition of a hydrophobic solute.

PubMed

Okamoto, Ryuichi; Onuki, Akira

2015-07-01

We show that phase separation can occur in a one-component liquid outside its coexistence curve (CX) with addition of a small amount of a solute. The solute concentration at the transition decreases with increasing the difference of the solvation chemical potential between liquid and gas. As a typical bubble-forming solute, we consider O2 in ambient liquid water, which exhibits mild hydrophobicity and its critical temperature is lower than that of water. Such a solute can be expelled from the liquid to form gaseous domains while the surrounding liquid pressure is higher than the saturated vapor pressure p cx. This solute-induced bubble formation is a first-order transition in bulk and on a partially dried wall, while a gas film grows continuously on a completely dried wall. We set up a bubble free energy ΔG for bulk and surface bubbles with a small volume fraction ϕ. It becomes a function of the bubble radius R under the Laplace pressure balance. Then, for sufficiently large solute densities above a threshold, ΔG exhibits a local maximum at a critical radius and a minimum at an equilibrium radius. We also examine solute-induced nucleation taking place outside CX, where bubbles larger than the critical radius grow until attainment of equilibrium.

Application of the "Full Cavitation Model" to the fundamental study of cavitation in liquid metal processing

NASA Astrophysics Data System (ADS)

Lebon, G. S. B.; Pericleous, K.; Tzanakis, I.; Eskin, D.

2015-01-01

Ultrasonic cavitation treatment of melt significantly improves the downstream properties and quality of conventional and advanced metallic materials. However, the transfer of this technology has been hindered by difficulties in treating large volumes of liquid metal. To improve the understanding of cavitation processing efficiency, the Full Cavitation Model, which is derived from a reduced form of the Rayleigh-Plesset equation, is modified and applied to the two-phase problem of bubble propagation in liquid melt. Numerical simulations of the sound propagation are performed in the microsecond time scale to predict the maximum and minimum acoustic pressure amplitude fields in the domain. This field is applied to the source term of the bubble transport equation to predict the generation and destruction of cavitation bubbles in a time scale relevant to the fluid flow. The use of baffles to limit flow speed in a launder conduit is studied numerically, to determine the optimum configuration that maximizes the residence time of the liquid in high cavitation activity regions. With this configuration, it is then possible to convert the batch processing of liquid metal into a continuous process. The numerical simulations will be validated against water and aluminium alloy experiments, carried out at Brunel University.

A disposable sampling device to collect volume-measured DBS directly from a fingerprick onto DBS paper.

PubMed

Lenk, Gabriel; Sandkvist, Sören; Pohanka, Anton; Stemme, Göran; Beck, Olof; Roxhed, Niclas

2015-01-01

DBS samples collected from a fingerprick typically vary in volume and homogeneity and hence make an accurate quantitative analysis of DBS samples difficult. We report a prototype which first defines a precise liquid volume and subsequently stores it to a conventional DBS matrix. Liquid volumes of 2.2 µl ± 7.1% (n = 21) for deionized water and 6.1 µl ± 8.8% (n = 15) for whole blood have been successfully metered and stored in DBS paper. The new method of collecting a defined volume of blood by DBS sampling has the potential to reduce assay bias for the quantitative evaluation of DBS samples while maintaining the simplicity of conventional DBS sampling.

A novel percussion type droplet-on-demand generator

NASA Astrophysics Data System (ADS)

Hussain, Taaha; Patel, Priyesh; Balachandran, Ramanarayanan; Ladommatos, Nicos

2015-01-01

Numerous engineering applications require generation of droplets on demand which are of high uniformity and constant size. The common method to produce droplets is to drive liquid at high pressure through a small orifice/nozzle. The liquid stream disintegrates into small droplets. However this method normally requires large volumes of liquid and is not suitable for applications where single droplets of constant size is required. Such applications require droplet-on-demand generators which commonly employ piezoelectric or pneumatic actuation. It is well known that piezoelectric generators are hard to employ at high pressure and, high temperature applications, and the pneumatic generators often produce satellite (secondary) droplets. This paper describes the development of a novel percussion type droplet-on-demand generator, which overcomes some of the above difficulties and is capable of producing single droplets on demand. The generator consists of a cylindrical liquid filled chamber with a small orifice at the bottom. The top of the chamber is covered with a thin flexible metal disc. A small metal pin is employed to hammer/impact the top metal surface to generate a pressure pulse inside the liquid chamber. The movement and the momentum of the metal pin are controlled using a solenoid device. The pressure pulse generated overcomes the surface tension of the liquid meniscus at the exit of the orifice and ejects a single droplet. The work presented in this paper will demonstrate the capabilities of the droplet generator.

Plexcitonics: Coupled and Plasmon-Exciton Systems with Tailorable Properties

DTIC Science & Technology

2013-11-14

demonstrated efficient steam generation from aqueous nanoparticles solutions without heating the bulk volume of the liquid. Application in ethanol ...solutions without heating the bulk volume of the liquid. Applications in ethanol distillation and sanitation have been demonstrated. Key Accomplishments...nanoparticle surface. This state-selective population of adsorbate resonances could be exploited to prepare reactants in specific states on nanoparticle

Deaf Children's Judgments on Conservation Problems of Liquid, Matter, Weight and Volume: A Pilot Study.

ERIC Educational Resources Information Center

Rittenhouse, Robert K.

Twenty-four profoundly deaf children (7 to 13 years old) from a residential school were presented with conservation problems of liquid, matter, weight, and volume. Analyses of variance showed that age was significant beyond the .01 level and type of task (conservation) at the .25 level. No significant sex effect was found. Differences among means…

Granular encapsulation of light hydrophobic liquids (LHL) in LHL-salt water systems: Particle induced densification with quartz sand.

PubMed

Boglaienko, Daria; Tansel, Berrin; Sukop, Michael C

2016-02-01

Addition of granular materials to floating crude oil slicks can be effective in capturing and densifying the floating hydrophobic phase, which settles by gravity. Interaction of light hydrophobic liquids (LHL) with quartz sand was investigated in LHL-salt water systems. The LHLs studied were decane, tetradecane, hexadecane, benzene, toluene, ethylbenzene, m-xylene, and 2-cholorotoluene. Experiments were conducted with fine quartz sand (passing sieve No. 40 with openings 0.425 mm). Each LHL was dyed with few crystals of Sudan IV dye for ease of visual observation. A volume of 0.5 mL of each LHL was added to 100 mL salt water (34 g/L). Addition of one gram of quartz sand to the floating hydrophobic liquid layer resulted in formation of sand-encapsulated globules, which settled due to increased density. All LHLs (except for a few globules of decane) formed globules covered with fine sand particles that were heavy enough to settle by gravity. The encapsulated globules were stable and retained their shape upon settling. Polarity of hydrophobic liquids as the main factor of aggregation with minerals was found to be insufficient to explain LHL aggregation with sand. Contact angle measurements were made by submerging a large quartz crystal with the LHL drop on its surface into salt water. A positive correlation was observed between the wetting angle of LHL and the LHL volume captured (r = 0.75). The dependence of the globule density on globule radius was analyzed in relation to the coverage (%) of globule surface (LHL-salt water interface) by fine quartz particles. Copyright © 2015 Elsevier Ltd. All rights reserved.

Self-powered Imbibing Microfluidic Pump by Liquid Encapsulation: SIMPLE.

PubMed

Kokalj, Tadej; Park, Younggeun; Vencelj, Matjaž; Jenko, Monika; Lee, Luke P

2014-11-21

Reliable, autonomous, internally self-powered microfluidic pumps are in critical demand for rapid point-of-care (POC) devices, integrated molecular-diagnostic platforms, and drug delivery systems. Here we report on a Self-powered Imbibing Microfluidic Pump by Liquid Encapsulation (SIMPLE), which is disposable, autonomous, easy to use and fabricate, robust, and cost efficient, as a solution for self-powered microfluidic POC devices. The imbibition pump introduces the working liquid which is sucked into a porous material (paper) upon activation. The suction of the working liquid creates a reduced pressure in the analytical channel and induces the sequential sample flow into the microfluidic circuits. It requires no external power or control and can be simply activated by a fingertip press. The flow rate can be programmed by defining the shape of utilized porous material: by using three different paper shapes with circular section angles 20°, 40° and 60°, three different volume flow rates of 0.07 μL s(-1), 0.12 μL s(-1) and 0.17 μL s(-1) are demonstrated at 200 μm × 600 μm channel cross-section. We established the SIMPLE pumping of 17 μL of sample; however, the sample volume can be increased to several hundreds of μL. To demonstrate the design, fabrication, and characterization of SIMPLE, we used a simple, robust and cheap foil-laminating fabrication technique. The SIMPLE can be integrated into hydrophilic or hydrophobic materials-based microfluidic POC devices. Since it is also applicable to large-scale manufacturing processes, we anticipate that a new chapter of a cost effective, disposable, autonomous POC diagnostic chip is addressed with this technical innovation.

Performance of exchange-correlation functionals in density functional theory calculations for liquid metal: A benchmark test for sodium.

PubMed

Han, Jeong-Hwan; Oda, Takuji

2018-04-14

The performance of exchange-correlation functionals in density-functional theory (DFT) calculations for liquid metal has not been sufficiently examined. In the present study, benchmark tests of Perdew-Burke-Ernzerhof (PBE), Armiento-Mattsson 2005 (AM05), PBE re-parameterized for solids, and local density approximation (LDA) functionals are conducted for liquid sodium. The pair correlation function, equilibrium atomic volume, bulk modulus, and relative enthalpy are evaluated at 600 K and 1000 K. Compared with the available experimental data, the errors range from -11.2% to 0.0% for the atomic volume, from -5.2% to 22.0% for the bulk modulus, and from -3.5% to 2.5% for the relative enthalpy depending on the DFT functional. The generalized gradient approximation functionals are superior to the LDA functional, and the PBE and AM05 functionals exhibit the best performance. In addition, we assess whether the error tendency in liquid simulations is comparable to that in solid simulations, which would suggest that the atomic volume and relative enthalpy performances are comparable between solid and liquid states but that the bulk modulus performance is not. These benchmark test results indicate that the results of liquid simulations are significantly dependent on the exchange-correlation functional and that the DFT functional performance in solid simulations can be used to roughly estimate the performance in liquid simulations.

Performance of exchange-correlation functionals in density functional theory calculations for liquid metal: A benchmark test for sodium

NASA Astrophysics Data System (ADS)

Han, Jeong-Hwan; Oda, Takuji

2018-04-01

The performance of exchange-correlation functionals in density-functional theory (DFT) calculations for liquid metal has not been sufficiently examined. In the present study, benchmark tests of Perdew-Burke-Ernzerhof (PBE), Armiento-Mattsson 2005 (AM05), PBE re-parameterized for solids, and local density approximation (LDA) functionals are conducted for liquid sodium. The pair correlation function, equilibrium atomic volume, bulk modulus, and relative enthalpy are evaluated at 600 K and 1000 K. Compared with the available experimental data, the errors range from -11.2% to 0.0% for the atomic volume, from -5.2% to 22.0% for the bulk modulus, and from -3.5% to 2.5% for the relative enthalpy depending on the DFT functional. The generalized gradient approximation functionals are superior to the LDA functional, and the PBE and AM05 functionals exhibit the best performance. In addition, we assess whether the error tendency in liquid simulations is comparable to that in solid simulations, which would suggest that the atomic volume and relative enthalpy performances are comparable between solid and liquid states but that the bulk modulus performance is not. These benchmark test results indicate that the results of liquid simulations are significantly dependent on the exchange-correlation functional and that the DFT functional performance in solid simulations can be used to roughly estimate the performance in liquid simulations.

Hairy root culture in a liquid-dispersed bioreactor: characterization of spatial heterogeneity.

PubMed

Williams, G R; Doran, P M

2000-01-01

A liquid-dispersed reactor equipped with a vertical mesh cylinder for inoculum support was developed for culture of Atropa belladonna hairy roots. The working volume of the culture vessel was 4.4 L with an aspect ratio of 1.7. Medium was dispersed as a spray onto the top of the root bed, and the roots grew radially outward from the central mesh cylinder to the vessel wall. Significant benefits in terms of liquid drainage and reduced interstitial liquid holdup were obtained using a vertical rather than horizontal support structure for the biomass and by operating the reactor with cocurrent air and liquid flow. With root growth, a pattern of spatial heterogeneity developed in the vessel. Higher local biomass densities, lower volumes of interstitial liquid, lower sugar concentrations, and higher root atropine contents were found in the upper sections of the root bed compared with the lower sections, suggesting a greater level of metabolic activity toward the top of the reactor. Although gas-liquid oxygen transfer to the spray droplets was very rapid, there was evidence of significant oxygen limitations in the reactor. Substantial volumes of non-free-draining interstitial liquid accumulated in the root bed. Roots near the bottom of the vessel trapped up to 3-4 times their own weight in liquid, thus eliminating the advantages of improved contact with the gas phase offered by liquid-dispersed culture systems. Local nutrient and product concentrations in the non-free-draining liquid were significantly different from those in the bulk medium, indicating poor liquid mixing within the root bed. Oxygen enrichment of the gas phase improved neither growth nor atropine production, highlighting the greater importance of liquid-solid compared with gas-liquid oxygen transfer resistance. The absence of mechanical or pneumatic agitation and the tendency of the root bed to accumulate liquid and impede drainage were identified as the major limitations to reactor performance. Improved reactor operating strategies and selection or development of root lines offering minimal resistance to liquid flow and low liquid retention characteristics are possible solutions to these problems.

Reduce volume of head-up display by image stitching

NASA Astrophysics Data System (ADS)

Chiu, Yi-Feng; Su, Guo-Dung J.

2016-09-01

Head-up Display (HUD) is a safety feature for automobile drivers. Although there have been some HUD systems in commercial product already, their images are too small to show assistance information. Another problem, the volume of HUD is too large. We proposed a HUD including micro-projectors, rear-projection screen, microlens array (MLA) and the light source is 28 mm x 14 mm realized a 200 mm x 100 mm image in 3 meters from drivers. We want to use the MLA to reduce the volume by virtual image stitching. We design the HUD's package dimensions is 12 cm x 12 cm x 9 cm. It is able to show speed, map-navigation and night vision information. We used Liquid Crystal Display (LCD) as our image source due to its brighter image output required and the minimum volume occupancy. The MLA is a multi aperture system. The proposed MLA consists of many optical channels each transmitting a segment of the whole field of view. The design of the system provides the stitching of the partial images, so that we can see the whole virtual image.

30 CFR 256.40 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... interest. (g) Liquefied petroleum products means natural gas liquid products including the following... liquids and nonhydrocarbon gases. (3) Of liquefied petroleum products means the volume of natural gas liquids produced from reservoir gas and liquefied at surface separators, field facilities, or gas...

A quantitative evaluation of pleural effusion on computed tomography scans using B-spline and local clustering level set.

PubMed

Song, Lei; Gao, Jungang; Wang, Sheng; Hu, Huasi; Guo, Youmin

2017-01-01

Estimation of the pleural effusion's volume is an important clinical issue. The existing methods cannot assess it accurately when there is large volume of liquid in the pleural cavity and/or the patient has some other disease (e.g. pneumonia). In order to help solve this issue, the objective of this study is to develop and test a novel algorithm using B-spline and local clustering level set method jointly, namely BLL. The BLL algorithm was applied to a dataset involving 27 pleural effusions detected on chest CT examination of 18 adult patients with the presence of free pleural effusion. Study results showed that average volumes of pleural effusion computed using the BLL algorithm and assessed manually by the physicians were 586 ml±339 ml and 604±352 ml, respectively. For the same patient, the volume of the pleural effusion, segmented semi-automatically, was 101.8% ±4.6% of that was segmented manually. Dice similarity was found to be 0.917±0.031. The study demonstrated feasibility of applying the new BLL algorithm to accurately measure the volume of pleural effusion.

Pressure-Volume-Temperature (PVT) Gauging of an Isothermal Cryogenic Propellant Tank Pressurized with Gaseous Helium

NASA Technical Reports Server (NTRS)

VanDresar, Neil T.; Zimmerli, Gregory A.

2014-01-01

Results are presented for pressure-volume-temperature (PVT) gauging of a liquid oxygen/liquid nitrogen tank pressurized with gaseous helium that was supplied by a high-pressure cryogenic tank simulating a cold helium supply bottle on a spacecraft. The fluid inside the test tank was kept isothermal by frequent operation of a liquid circulation pump and spray system, and the propellant tank was suspended from load cells to obtain a high-accuracy reference standard for the gauging measurements. Liquid quantity gauging errors of less than 2 percent of the tank volume were obtained when quasi-steady-state conditions existed in the propellant and helium supply tanks. Accurate gauging required careful attention to, and corrections for, second-order effects of helium solubility in the liquid propellant plus differences in the propellant/helium composition and temperature in the various plumbing lines attached to the tanks. On the basis of results from a helium solubility test, a model was developed to predict the amount of helium dissolved in the liquid as a function of cumulative pump operation time. Use of this model allowed correction of the basic PVT gauging calculations and attainment of the reported gauging accuracy. This helium solubility model is system specific, but it may be adaptable to other hardware systems.

Heat capacity measurements of sub-nanoliter volumes of liquids using bimaterial microchannel cantilevers

NASA Astrophysics Data System (ADS)

Khan, M. F.; Miriyala, N.; Lee, J.; Hassanpourfard, M.; Kumar, A.; Thundat, T.

2016-05-01

Lab-on-a-Chip compatible techniques for thermal characterization of miniaturized volumes of liquid analytes are necessary in applications such as protein blotting, DNA melting, and drug development, where samples are either rare or volume-limited. We developed a closed-chamber calorimeter based on a bimaterial microchannel cantilever (BMC) for sub-nanoliter level thermal analysis. When the liquid-filled BMC is irradiated with infrared (IR) light at a specific wavelength, the IR absorption by the liquid analyte results in localized heat generation and the subsequent deflection of the BMC, due to a thermal expansion mismatch between the constituent materials. The time constant of the deflection, which is dependent upon the heat capacity of the liquid analyte, can be directly measured by recording the time-dependent bending of the BMC. We have used the BMC to quantitatively measure the heat capacity of five volatile organic compounds. With a deflection noise level of ˜10 nm and a signal-to-noise ratio of 68:1, the BMC offers a sensitivity of 30.5 ms/(J g-1 K-1) and a resolution of 23 mJ/(g K) for ˜150 pl liquid for heat capacity measurements. This technique can be used for small-scale thermal characterization of different chemical and biological samples.

On Thermocapillary Mechanism of Spatial Separation of Metal Melts

NASA Astrophysics Data System (ADS)

Demin, V. A.; Mizev, A. I.; Petukhov, M. I.

2018-02-01

Theoretical research has been devoted to the study of binary metal melts behavior in a thin capillary. Earlier it has been found experimentally that unusually significant and quick redistribution of melts components takes place along capillary after the cooling. Numerical simulation of concentration-induced convection has been carried out to explain these experimental data. Two-component melt of both liquid metals filling vertical thin capillary with non-uniform temperature distribution on the boundaries is considered. It is assumed that the condition of absolute non-wetting is valid on the sidewalls. Because of this effect there is a free surface on vertical boundaries, where thermocapillary force is appeared due to the external longitudinal temperature gradient. It makes to move liquid elements at a big distance, compared with axial size of capillary. Effects of adsorption-desorption on the surface, thermal and concentration-capillary forces, convective motion in a volume and diffusion generate the large-scale circulation. This process includes the admixture carrying-out on the surface in the more hot higher part of the channel, its following transfer down along the boundary due to the thermocapillary force and its return in the volume over the desorption in the lower part of capillary. Intensity of motion and processes of adsorption-desorption on the free boundary have the decisive influence upon the formation of concentration fields and speed of components redistribution. Thus, one of the possible mechanisms of longitudinal division on components of liquid binary mixtures in thin channels has been demonstrated.

The extraction of bitumen from western oil sands: Volume 2. Final report

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

Oblad, A.G.; Dahlstrom, D.A.; Deo, M.D.

1997-11-26

The program is composed of 20 projects, of which 17 are laboratory bench or laboratory pilot scale processes or computer process simulations that are performed in existing facilities on the University of Utah campus in north-east Salt Lake City. These tasks are: (1) coupled fluidized-bed bitumen recovery and coked sand combustion; (2) water-based recovery of bitumen; (3) oil sand pyrolysis in a continuous rotary kiln reactor; (4) oil sand pyrolysis in a large diameter fluidized bed reactor; (5) oil sand pyrolysis in a small diameter fluidized bed reactor; (6) combustion of spent sand in a transport reactor; (7) recovery andmore » upgrading of oil sand bitumen using solvent extraction methods; (8) fixed-bed hydrotreating of Uinta Basin bitumens and bitumen-derived hydrocarbon liquids; (9) ebullieted bed hydrotreating of bitumen and bitumen derived liquids; (10) bitumen upgrading by hydropyrolysis; (11) evaluation of Utah`s major oil sand deposits for the production of asphalt, high-energy jet fuels and other specialty products; (12) characterization of the bitumens and reservoir rocks from the Uinta Basin oil sand deposits; (13) bitumen upgrading pilot plant recommendations; (14) liquid-solid separation and fine tailings thickening; (15) in-situ production of heavy oil from Uinta Basin oil sand deposits; (16) oil sand research and development group analytical facility; and (17) process economics. This volume contains reports on nine of these projects, references, and a bibliography. 351 refs., 192 figs., 65 tabs.« less

Analysis of Xylem Sap from Functional (Nonembolized) and Nonfunctional (Embolized) Vessels of Populus nigra: Chemistry of Refilling1[C][W][OA

PubMed Central

Secchi, Francesca; Zwieniecki, Maciej A.

2012-01-01

It is assumed that the refilling of drought-induced embolism requires the creation of an osmotic gradient between xylem parenchyma cells and vessel lumens to generate the water efflux needed to fill the void. To assess the mechanism of embolism repair, it is crucial to determine if plants can up-regulate the efflux of osmotically active substances into embolized vessels and identify the major components of the released osmoticum. Here, we introduce a new approach of sap collection designed to separate water from nonembolized (functional) and embolized (nonfunctional) vessels. This new approach made possible the chemical analysis of liquid collected from both types of vessels in plants subjected to different levels of water stress. The technique also allowed us to determine the water volumes in nonfunctional vessels as a function of stress level. Overall, with the increase of water stress in plants, the osmotic potential of liquid collected from nonfunctional vessels increased while its volume decreased. These results revealed the presence of both sugars and ions in nonfunctional vessels at elevated levels in comparison with liquid collected from functional vessels, in which only traces of sugars were found. The increased sugar concentration was accompanied by decreased xylem sap pH. These results provide new insight into the biology of refilling, underlining the role of sugar and sugar transporters, and imply that a large degree of hydraulic compartmentalization must exist in the xylem during the refilling process. PMID:22837359

A new approach to stability and oscillations of constrained drops and capillary bridges

NASA Astrophysics Data System (ADS)

Fabre, David; Chireux, Veronique; Risso, Frederic; Tordjeman, Philippe

2014-11-01

Static equilibria of liquid inclusions under the effect of gravity and capillarity is a large class of situations which encompasses drops hanging from a ceiling or from a capillary, sessile drops, liquid bridges, etc... In such equilibria the surface shape is governed by the Yong-Laplace equation, which is usually solved in a local way using a ``shooting'' method. We introduce a new method which solves the Laplace-Young in a global way, using an iterative deformation of the shape towards the equilibrium shape. The method is easy to implement and versatile, and allows to prescribe constraints such as the volume of liquid, the angle of attachment, etc... We subsequently consider the issue of stability and oscillations of such configurations. Using finite elements and considering small-amplitude displacements of the surface with respect to the static configuration previously computed, we introduce a global stability approach which allows to predict the stability limits, the oscillation frequencies and the eigenmode shapes for quite general geometries. The approach will be illustrated and compared with experiments in two situations, namely a drop attached to a capilary and a liquid bridge resulting from the coalescence of two facing millimetric drops.

Liquid Rocket Booster Study. Volume 2, Book 1

NASA Technical Reports Server (NTRS)

1989-01-01

The recommended Liquid Rocket Booster (LRB) concept is shown which uses a common main engine with the Advanced Launch System (ALS) which burns LO2 and LH2. The central rationale is based on the belief that the U.S. can only afford one big new rocket engine development in the 1990's. A LO2/LH2 engine in the half million pound thrust class could satisfy STS LRB, ALS, and Shuttle C (instead of SSMEs). Development costs and higher production rates can be shared by NASA and USAF. If the ALS program does not occur, the LO2/RP-1 propellants would produce slight lower costs for and STS LRB. When the planned Booster Engine portion of the Civil Space Transportation Initiatives has provided data on large pressure fed LO2/RP-1 engines, then the choice should be reevaluated.

Experimental Study on Scale-Up of Solid-Liquid Stirred Tank with an Intermig Impeller

NASA Astrophysics Data System (ADS)

Zhao, Hongliang; Zhao, Xing; Zhang, Lifeng; Yin, Pan

2017-02-01

The scale-up of a solid-liquid stirred tank with an Intermig impeller was characterized via experiments. Solid concentration, impeller just-off-bottom speed and power consumption were measured in stirred tanks of different scales. The scale-up criteria for achieving the same effect of solid suspension in small-scale and large-scale vessels were evaluated. The solids distribution improves if the operating conditions are held constant as the tank is scaled-up. The results of impeller just-off-bottom speed gave X = 0.868 in the scale-up relationship ND X = constant. Based on this criterion, the stirring power per unit volume obviously decreased at N = N js, and the power number ( N P) was approximately equal to 0.3 when the solids are uniformly distributed in the vessels.

Resonance-inclined optical nuclear spin polarization of liquids in diamond structures

NASA Astrophysics Data System (ADS)

Chen, Q.; Schwarz, I.; Jelezko, F.; Retzker, A.; Plenio, M. B.

2016-02-01

Dynamic nuclear polarization (DNP) of molecules in a solution at room temperature has the potential to revolutionize nuclear magnetic resonance spectroscopy and imaging. The prevalent methods for achieving DNP in solutions are typically most effective in the regime of small interaction correlation times between the electron and nuclear spins, limiting the size of accessible molecules. To solve this limitation, we design a mechanism for DNP in the liquid phase that is applicable for large interaction correlation times. Importantly, while this mechanism makes use of a resonance condition similar to solid-state DNP, the polarization transfer is robust to a relatively large detuning from the resonance due to molecular motion. We combine this scheme with optically polarized nitrogen-vacancy (NV) center spins in nanodiamonds to design a setup that employs optical pumping and is therefore not limited by room temperature electron thermal polarization. We illustrate numerically the effectiveness of the model in a flow cell containing nanodiamonds immobilized in a hydrogel, polarizing flowing water molecules 4700-fold above thermal polarization in a magnetic field of 0.35 T, in volumes detectable by current NMR scanners.

Controllable synthesis of nitrogen-doped hollow mesoporous carbon spheres using ionic liquids as template for supercapacitors

NASA Astrophysics Data System (ADS)

Chen, Aibing; Li, Yunqian; Liu, Lei; Yu, Yifeng; Xia, Kechan; Wang, Yuying; Li, Shuhui

2017-01-01

We have demonstrated a facile and controllable synthesis of monodispersed nitrogen-doped hollow mesoporous carbon spheres (N-HMCSs) using resorcinol/formaldehyde resin as a carbon precursor, tetraethyl orthosilicate as a structure-assistant agent, ionic liquids (ILs) as soft template, partial carbon sources, and nitrogen sources. The sizes and the architectures including hollow and yolk-shell of resultant carbon spheres can be efficiently controlled through the adjustment of the content of ILs. Alkyl chain length of the ILs also has an important effect on the formation of N-HMCSs. With proper alkyl chain length and content of ILs, the resultant N-HMCSs show monodispersed hollow spheres with high surface areas (up to 1158 m2 g-1), large pore volumes (up to 1.70 cm3 g-1), and uniform mesopore size (5.0 nm). Combining the hollow mesoporous structure, high porosity, large surface area, and nitrogen functionality, the as-synthesized N-HMCSs have good supercapacitor performance with good capacitance (up to 159 F g-1) and favorable capacitance retention (88% capacitive retention after 5000 cycles).

The role of compressional viscoelasticity in the lubrication of rolling contacts.

NASA Technical Reports Server (NTRS)

Harrison, G.; Trachman, E. G.

1972-01-01

A simple model for the time-dependent volume response of a liquid to an applied pressure step is used to calculate the variation with rolling speed of the traction coefficient in a rolling contact system. Good agreement with experimental results is obtained at rolling speeds above 50 in/sec. At lower rolling speeds a very rapid change in the effective viscosity of the lubricant is predicted. This behavior, in conjunction with shear rate effects, is shown to lead to large errors when experimental data are extrapolated to zero rolling speed.

Numerical Investigation of Liquid Carryover in T-Junction with Different Diameter Ratios

NASA Astrophysics Data System (ADS)

Pao, William; Sam, Ban; Saieed, Ahmed; Tran, Cong Minh

2018-03-01

In offshore Malaysia, T-junction is installed at the production header as a compact separator to tap produced gas from reservoir as fuel gas for power generation. However, excessive liquid carryover in T-junction presents a serious operational issue because it trips the whole production platform. The primary objective of present study is to numerically investigate the liquid carryover due to formation of slug, subsequently its liquid carryover at different diameter ratio. The analyses were carried out on a model with 0.0254 m (1 inch) diameter horizontal main arm and a vertically upward side arm using Volume of Fluid Method. Three different sides to main arm diameter ratio of 1.0, 0.5 and 0.3 were investigated with different gas and liquid superficial velocities. The results showed that, while the general trend is true that smaller diameter ratio T-junction has lesser liquid take off capacity, it has a very high frequency of low liquid carryover threshold. In other words, under slug flow, smaller diameter ratio T-junction is constantly transporting liquid even though at a lesser volume in comparison to regular T-junction.

Rapid analysis of ultraviolet filters using dispersive liquid-liquid microextraction coupled to headspace gas chromatography and mass spectrometry.

PubMed

Pierson, Stephen A; Trujillo-Rodríguez, María J; Anderson, Jared L

2018-05-29

An ionic-liquid-based in situ dispersive liquid-liquid microextraction method coupled to headspace gas chromatography and mass spectrometry was developed for the rapid analysis of ultraviolet filters. The chemical structures of five ionic liquids were specifically designed to incorporate various functional groups for the favorable extraction of the target analytes. Extraction parameters including ionic liquid mass, molar ratio of ionic liquid to metathesis reagent, vortex time, ionic strength, pH, and total sample volume were studied and optimized. The effect of the headspace temperature and volume during the headspace sampling step was also evaluated to increase the sensitivity of the method. The optimized procedure is fast as it only required ∼7-10 min per extraction and allowed for multiple extractions to be performed simultaneously. In addition, the method exhibited high precision, good linearity, and low limits of detection for six ultraviolet filters in aqueous samples. The developed method was applied to both pool and lake water samples attaining acceptable relative recovery values. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Probing Hydrogen Diffusion under High Pressure

NASA Astrophysics Data System (ADS)

Bove, L. E.; Klotz, S.; Strassle, T.; Saitta, M.

2012-12-01

The study of the microscopic mechanism governing hydrogen and hydrogen-based liquids (as water, ammonia and methane) diffusion is crucial for a variety of scientific issues spanning most of natural sciences. As an example, characterizing hydrogen diffusion in a confined medium, like in porous systems or zeolites, is fundamental in problems relating to environment, hydrogen storage and industrial applications [1]. The presence of water diffusion in the minerals of the Earth's mantle have strong incidence on the processes governing volcanic eruptions and intermediate-depth seismicity. As last example, knowing in details the microscopic dynamics of hydrogen-based simple liquids under extreme conditions is essential in order to interpret observations and develop models of planet interiors [2]. On the other hand, water and other simple hydrogen-based liquids have always been key systems in the development of modern condensed-matter physics, because of their simple electronic structure and the peculiar properties deriving from the hydrogen-bond network. Their high compressibility and chemical reactivity have made these systems very challenging to study experimentally under static high P-T conditions. In the last few years, a large effort has been undertaken by several groups around the world [2] to extend the static and dynamic techniques to high temperatures and pressures, a program in which our group has been actively involved [3-6]. However, while the structure of water and other hydrogenated liquids of geological interest, is now known up to almost 20 GPa, the study of their transport properties greatly lags behind. We have recently developed a new large-volume gasket-anvil ensemble for the Paris-Edinburgh press based on a novel toroidal design [7], which allows to perform quasi elastic neutron scattering measurements on hydrogen based liquids up to one order of magnitude higher pressures (5 GPa) respect to what was achievable with standard methods [8]. The large volume HP press can be now warmed up to 600K and the peculiar geometry of the gasket assure an excellent signal to background ratio. This new device has been recently settled up on neutron scattering facilities (PSI, ILL), successfully showing that very high quality data can be obtained on liquid water, and more generally on hydrogenated liquids dynamics under high pressure. Some new exciting results on the diffusion mechanism in hot dense water will be presented [9]. Possible future implementation of the device to reach the 20GPa and 1000K conditions will be also discussed. References [1] C. Cavazzoni et al., Science 283, 44 (1999) ; T. Guillot, Science 286 (1999), 72 . 77. [2] Some of the most active groups in this field are the Geophysical Laboratory (USA), Lawrence Livermore National Laboratory (USA), CEA/DAM (France) and the Bayerisches Geoinstitut (Allemagne). [3] Klotz S et al, Phys. Rev. Lett. 96 149602, 2006. [4] Nelmes R J Nature Phys. 2 414, 2006. [5] S. Klotz, L. Bove et al., Nature Mat. 8, 405 (2009). [6] L.E. Bove et al., Phys. Rev. Lett., 106 (2011) . [7] L. E. Bove et al., Phys. Appl. Lett., in preparation (2012). [8] A. Cunsolo et al., Journal of Chem. Phys. 124, 084503 (2006). [9] L.E. Bove et al., Phys. Rev. Lett., submitted (2012) .

30 CFR 256.40 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... products means natural gas liquid products including the following: ethane, propane, butane, pentane... resulting from the removal of natural gas liquids and nonhydrocarbon gases. (3) Of liquefied petroleum products means the volume of natural gas liquids produced from reservoir gas and liquefied at surface...

30 CFR 556.40 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... products means natural gas liquid products including the following: ethane, propane, butane, pentane... resulting from the removal of natural gas liquids and nonhydrocarbon gases. (3) Of liquefied petroleum products mean the volume of natural gas liquids produced from reservoir gas and liquefied at surface...

30 CFR 556.40 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... products means natural gas liquid products including the following: ethane, propane, butane, pentane... resulting from the removal of natural gas liquids and nonhydrocarbon gases. (3) Of liquefied petroleum products mean the volume of natural gas liquids produced from reservoir gas and liquefied at surface...

30 CFR 556.40 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... products means natural gas liquid products including the following: ethane, propane, butane, pentane... resulting from the removal of natural gas liquids and nonhydrocarbon gases. (3) Of liquefied petroleum products mean the volume of natural gas liquids produced from reservoir gas and liquefied at surface...

Capillary forces exerted by liquid drops caught between crossed cylinders. A 3-D meniscus problem with free contact line

NASA Technical Reports Server (NTRS)

Patzek, T. W.; Scriven, L. E.

1982-01-01

The Young-Laplace equation is solved for three-dimensional menisci between crossed cylinders, with either the contact line fixed or the contact angle prescribed, by means of the Galerkin/finite element method. Shapes are computed, and with them the practically important quantities: drop volume, wetted area, capillary pressure force, surface tension force, and the total force exerted by the drop on each cylinder. The results show that total capillary force between cylinders increases with decreasing contact angle, i.e. with better wetting. Capillary force is also increases with decreasing drop volume, approaching an asymptotic limit. However, the wetted area on each cylinder decreases with decreasing drop volume, which raises the question of the optimum drop volume to strive for, when permanent bonding is sought from solidified liquid. For then the strength of the bond is likely to depend upon the area of contact, which is the wetted area when the bonding agent was introduced in liquid form.

A combined volume-of-fluid method and low-Mach-number approach for DNS of evaporating droplets in turbulence

NASA Astrophysics Data System (ADS)

Dodd, Michael; Ferrante, Antonino

2017-11-01

Our objective is to perform DNS of finite-size droplets that are evaporating in isotropic turbulence. This requires fully resolving the process of momentum, heat, and mass transfer between the droplets and surrounding gas. We developed a combined volume-of-fluid (VOF) method and low-Mach-number approach to simulate this flow. The two main novelties of the method are: (i) the VOF algorithm captures the motion of the liquid gas interface in the presence of mass transfer due to evaporation and condensation without requiring a projection step for the liquid velocity, and (ii) the low-Mach-number approach allows for local volume changes caused by phase change while the total volume of the liquid-gas system is constant. The method is verified against an analytical solution for a Stefan flow problem, and the D2 law is verified for a single droplet in quiescent gas. We also demonstrate the schemes robustness when performing DNS of an evaporating droplet in forced isotropic turbulence.

High-pressure liquid chromatography with direct injection of gas sample.

PubMed

Astanin, Anton I; Baram, Grigory I

2017-06-09

The conventional method of using liquid chromatography to determine the composition of a gaseous mixture entails dissolving vapors in a suitable solvent, then obtaining a chromatograph of the resulting solution. We studied the direct introduction of a gaseous sample into a C18 reversed-phase column, followed by separation of the components by HPLC with UV detection. Since the chromatography was performed at high pressure, vapors readily dissolved in the eluent and the substances separated in the column as effectively as in liquid samples. Samples were injected into the column in two ways: a) through the valve without a flow stop; b) after stopping the flow and relieving all pressure. We showed that an injectable gas volume could reach 70% of column dead volume. When an injected gaseous sample volume was less than 10% of the column dead volume, the resulting peaks were symmetrical and the column efficiency was high. Copyright © 2017 Elsevier B.V. All rights reserved.

A New Approach to Determine the Density of Liquids and Solids without Measuring Mass and Volume: Introducing the "Solidensimeter"

ERIC Educational Resources Information Center

Kiriktas, Halit; Sahin, Mehmet; Eslek, Sinan; Kiriktas, Irem

2018-01-01

This study aims to design a mechanism with which the density of any solid or liquid can be determined without measuring its mass and volume in order to help students comprehend the concept of density more easily. The "solidensimeter" comprises of two scaled and nested glass containers (graduated cylinder or beaker) and sufficient water.…

Decontamination of Nuclear Liquid Wastes Status of CEA and AREVA R and D: Application to Fukushima Waste Waters - 12312

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

Fournel, B.; Barre, Y.; Lepeytre, C.

2012-07-01

Liquid wastes decontamination processes are mainly based on two techniques: Bulk processes and the so called Cartridges processes. The first technique has been developed for the French nuclear fuel reprocessing industry since the 60's in Marcoule and La Hague. It is a proven and mature technology which has been successfully and quickly implemented by AREVA at Fukushima site for the processing of contaminated waters. The second technique, involving cartridges processes, offers new opportunities for the use of innovative adsorbents. The AREVA process developed for Fukushima and some results obtained on site will be presented as well as laboratory scale resultsmore » obtained in CEA laboratories. Examples of new adsorbents development for liquid wastes decontamination are also given. A chemical process unit based on co-precipitation technique has been successfully and quickly implemented by AREVA at Fukushima site for the processing of contaminated waters. The asset of this technique is its ability to process large volumes in a continuous mode. Several chemical products can be used to address specific radioelements such as: Cs, Sr, Ru. Its drawback is the production of sludge (about 1% in volume of initial liquid volume). CEA developed strategies to model the co-precipitation phenomena in order to firstly minimize the quantity of added chemical reactants and secondly, minimize the size of co-precipitation units. We are on the way to design compact units that could be mobilized very quickly and efficiently in case of an accidental situation. Addressing the problem of sludge conditioning, cementation appears to be a very attractive solution. Fukushima accident has focused attention on optimizations that should be taken into account in future studies: - To better take account for non-typical aqueous matrixes like seawater; - To enlarge the spectrum of radioelements that can be efficiently processed and especially short lives radioelements that are usually less present in standard effluents resulting from nuclear activities; - To develop reversible solid adsorbents for cartridge-type applications in order to minimize wastes. (authors)« less

Measurement Corner: Volume, Temperature and Pressure

ERIC Educational Resources Information Center

Teates, Thomas G.

1977-01-01

Boyle's Law and basic relationships between volume and pressure of a gas at constant temperature are presented. Suggests two laboratory activities for demonstrating the effect of temperature on the volume of a gas or liquid. (CS)

Survey of stranded gas and delivered costs to Europe of selected gas resources

USGS Publications Warehouse

Attanasi, E.D.; Freeman, P.A.

2011-01-01

Two important trends affecting the expected growth of global gas markets are (1) the shift by many industrialized countries from coal-fired electricity generation to the use of natural gas to generate electricity and (2) the industrialization of the heavily populated Asian countries of India and China. This paper surveys discovered gas in stranded conventional gas accumulations and presents estimates of the cost of developing and producing stranded gas in selected countries. Stranded gas is natural gas in discovered or identified fields that is not currently commercially producible for either physical or economic reasons. Published reserves of gas at the global level do not distinguish between volumes of gas in producing fields and volumes in nonproducing fields. Data on stranded gas reported here-that is the volumes, geographical distribution, and size distributions of stranded gas fields at the country and regional level-are based on the examination of individual-field data and represent a significant improvement in information available to industry and government decision makers. Globally, stranded gas is pervasive, but large volumes in large accumulations are concentrated in only a few areas. The cost component of the paper focuses on stranded conventional gas accumulations in Africa and South America that have the potential to augment supplies to Europe. The methods described for the computation of extraction and transport costs are innovative in that they use information on the sizes and geographical distribution of the identified stranded gas fields. The costs are based on industry data specific to the country and geologic basin where the stranded gas is located. Gas supplies to Europe can be increased significantly at competitive costs by the development of stranded gas. Net extraction costs of producing the identified gas depend critically on the natural-gas-liquids (NGLs) content, the prevailing prices of liquids, the size of the gas accumulation, and the deposit's location. The diversity of the distribution of stranded gas is one obstacle to the exercise of market power by the Gas Exporting Countries Forum (GECF). Copyright ?? 2011 Society of Petroleum Engineers.

Turbulence-assisted shear exfoliation of graphene using household detergent and a kitchen blender

NASA Astrophysics Data System (ADS)

Varrla, Eswaraiah; Paton, Keith R.; Backes, Claudia; Harvey, Andrew; Smith, Ronan J.; McCauley, Joe; Coleman, Jonathan N.

2014-09-01

To facilitate progression from the lab to commercial applications, it will be necessary to develop simple, scalable methods to produce high quality graphene. Here we demonstrate the production of large quantities of defect-free graphene using a kitchen blender and household detergent. We have characterised the scaling of both graphene concentration and production rate with the mixing parameters: mixing time, initial graphite concentration, rotor speed and liquid volume. We find the production rate to be invariant with mixing time and to increase strongly with mixing volume, results which are important for scale-up. Even in this simple system, concentrations of up to 1 mg ml-1 and graphene masses of >500 mg can be achieved after a few hours mixing. The maximum production rate was ~0.15 g h-1, much higher than for standard sonication-based exfoliation methods. We demonstrate that graphene production occurs because the mean turbulent shear rate in the blender exceeds the critical shear rate for exfoliation.To facilitate progression from the lab to commercial applications, it will be necessary to develop simple, scalable methods to produce high quality graphene. Here we demonstrate the production of large quantities of defect-free graphene using a kitchen blender and household detergent. We have characterised the scaling of both graphene concentration and production rate with the mixing parameters: mixing time, initial graphite concentration, rotor speed and liquid volume. We find the production rate to be invariant with mixing time and to increase strongly with mixing volume, results which are important for scale-up. Even in this simple system, concentrations of up to 1 mg ml-1 and graphene masses of >500 mg can be achieved after a few hours mixing. The maximum production rate was ~0.15 g h-1, much higher than for standard sonication-based exfoliation methods. We demonstrate that graphene production occurs because the mean turbulent shear rate in the blender exceeds the critical shear rate for exfoliation. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr03560g

Change of hydrogen bonding structure in ionic liquid mixtures by anion type

NASA Astrophysics Data System (ADS)

Cha, Seoncheol; Kim, Doseok

2018-05-01

Ionic liquid mixtures have gained attention as a way of tuning material properties continuously with composition changes. For some mixture systems, physicochemical properties such as excess molar volume have been found to be significantly different from the value expected by linear interpolation, but the origin of this deviation is not well understood yet. The microstructure of the mixture, which can range from an ideal mixture of two initial consisting ionic liquids to a different structure from those of pure materials, has been suggested as the origin of the observed deviation. The structures of several different ionic liquid mixtures are studied by IR spectroscopy to confirm this suggestion, as a particular IR absorption band (νC(2)-D) for the moiety participating in the hydrogen bonding changes sensitively with the change of the anion in the ionic liquid. The absorbance of νC(2)-D changes proportionally with the composition, and a relatively small excess molar volume is observed for the mixtures containing an electronegative halide anion. By contrast, the absorbance changes nonlinearly, and the excess molar volumes are larger for the mixtures of which one of the anions has multiple interaction sites.

Drops spreading on flexible fibers

NASA Astrophysics Data System (ADS)

Somszor, Katarzyna; Boulogne, François; Sauret, Alban; Dressaire, Emilie; Stone, Howard

2015-11-01

Fibrous media are encountered in many engineered systems such as textile, paper and insulating materials. In most of these materials, fibers are randomly oriented and form a complex network in which drops of wetting liquid tend to accumulate at the nodes of the network. Here we investigate the role of the fiber flexibility on the spreading of a small volume of liquid on a pair of crossed flexible fibers. A drop of silicone oil is dispensed at the point of contact of the fibers and we characterize the liquid morphologies as we vary the volume of liquid, the angle between the fibers, and the length and bending modulus of the fibers. Drop morphologies previously reported for rigid fibers, i.e. a drop, a column and a mixed morphology, are also observed on flexible fibers with modified domains of existence. Moreover, at small inclination angles of the fibers, a new behavior is observed: the fibers bend and collapse. Depending on the volume, the liquid can adopt a column or a mixed morphology on the collapsed fibers. We rationalize our observations with a model based on energetic considerations. Our study suggests that the fiber flexibility adds a rich variety of behaviors that can be crucial for industrial applications.

Phospholipid component volumes: determination and application to bilayer structure calculations.

PubMed

Armen, R S; Uitto, O D; Feller, S E

1998-08-01

We present a new method for the determination of bilayer structure based on a combination of computational studies and laboratory experiments. From molecular dynamics simulations, the volumes of submolecular fragments of saturated and unsaturated phosphatidylcholines in the liquid crystalline state have been extracted with a precision not available experimentally. Constancy of component volumes, both among different lipids and as a function of membrane position for a given lipid, have been examined. The component volumes were then incorporated into the liquid crystallographic method described by Wiener and White (1992. Biophys. J. 61:434-447, and references therein) for determining the structure of a fluid-phase dioleoylphosphatidylcholine bilayer from x-ray and neutron diffraction experiments.

Phospholipid component volumes: determination and application to bilayer structure calculations.

PubMed Central

Armen, R S; Uitto, O D; Feller, S E

1998-01-01

We present a new method for the determination of bilayer structure based on a combination of computational studies and laboratory experiments. From molecular dynamics simulations, the volumes of submolecular fragments of saturated and unsaturated phosphatidylcholines in the liquid crystalline state have been extracted with a precision not available experimentally. Constancy of component volumes, both among different lipids and as a function of membrane position for a given lipid, have been examined. The component volumes were then incorporated into the liquid crystallographic method described by Wiener and White (1992. Biophys. J. 61:434-447, and references therein) for determining the structure of a fluid-phase dioleoylphosphatidylcholine bilayer from x-ray and neutron diffraction experiments. PMID:9675175

Measurement of activity coefficients of mixtures by head-space gas chromatography: general procedure.

PubMed

Luis, Patricia; Wouters, Christine; Van der Bruggen, Bart; Sandler, Stanley I

2013-08-09

Head-space gas chromatography (HS-GC) is an applicable method to perform vapor-liquid equilibrium measurements and determine activity coefficients. However, the reproducibility of the data may be conditioned by the experimental procedure concerning to the automated pressure-balanced system. The study developed in this work shows that a minimum volume of liquid in the vial is necessary to ensure the reliability of the activity coefficients since it may become a parameter that influences the magnitude of the peak areas: the helium introduced during the pressurization step may produce significant variations of the results when too small volume of liquid is selected. The minimum volume required should thus be evaluated prior to obtain experimentally the concentration in the vapor phase and the activity coefficients. In this work, the mixture acetonitrile-toluene is taken as example, requiring a sample volume of more than 5mL (about more than 25% of the vial volume). The vapor-liquid equilibrium and activity coefficients of mixtures at different concentrations (0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 molar fraction) and four temperatures (35, 45, 55 and 70°C) have been determined. Relative standard deviations (RSD) lower than 5% have been obtained, indicating the good reproducibility of the method when a sample volume larger than 5mL is used. Finally, a general procedure to measure activity coefficients by means of pressure-balanced head-space gas chromatography is proposed. Copyright © 2013 Elsevier B.V. All rights reserved.

Design of Accumulators and Liquid/Gas Charging of Single Phase Mechanically Pumped Fluid Loop Heat Rejection Systems

NASA Technical Reports Server (NTRS)

Bhandari, Pradeep; Dudik, Brenda; Birur, Gajanana; Karlmann, Paul; Bame, David; Mastropietro, A. J.

2012-01-01

For single phase mechanically pumped fluid loops used for thermal control of spacecraft, a gas charged accumulator is typically used to modulate pressures within the loop. This is needed to accommodate changes in the working fluid volume due to changes in the operating temperatures as the spacecraft encounters varying thermal environments during its mission. Overall, the three key requirements on the accumulator to maintain an appropriate pressure range throughout the mission are: accommodation of the volume change of the fluid due to temperature changes, avoidance of pump cavitation and prevention of boiling in the liquid. The sizing and design of such an accumulator requires very careful and accurate accounting of temperature distribution within each element of the working fluid for the entire range of conditions expected, accurate knowledge of volume of each fluid element, assessment of corresponding pressures needed to avoid boiling in the liquid, as well as the pressures needed to avoid cavitation in the pump. The appropriate liquid and accumulator strokes required to accommodate the liquid volume change, as well as the appropriate gas volumes, require proper sizing to ensure that the correct pressure range is maintained during the mission. Additionally, a very careful assessment of the process for charging both the gas side and the liquid side of the accumulator is required to properly position the bellows and pressurize the system to a level commensurate with requirements. To achieve the accurate sizing of the accumulator and the charging of the system, sophisticated EXCEL based spreadsheets were developed to rapidly come up with an accumulator design and the corresponding charging parameters. These spreadsheets have proven to be computationally fast and accurate tools for this purpose. This paper will describe the entire process of designing and charging the system, using a case study of the Mars Science Laboratory (MSL) fluid loops, which is en route to Mars for an August 2012 landing.

Piezo- and solenoid valve-based liquid dispensing for miniaturized assays.

PubMed

Niles, Walter D; Coassin, Peter J

2005-04-01

Miniaturization of biological assays requires dispensing liquids in the submicroliter range of volumes. Accuracy and reproducibility of dispensing this range depend on both the dispenser and the receptacle in which the assay is constructed. Miniaturization technologies developed by Aurora Discovery, Inc. (San Diego, CA) include high-density multiwell plates for assay samples and reagent storage, as well as piezo-based and solenoid valve-based liquid dispensers. Some basic principles of small-volume dispensing by jetting are described to provide context for dispenser design and function. Performance of the latest instruments incorporating these dispensing devices is presented.

Magnetic Resonance Imaging Quantification of Fasted State Colonic Liquid Pockets in Healthy Humans.

PubMed

Murray, Kathryn; Hoad, Caroline L; Mudie, Deanna M; Wright, Jeff; Heissam, Khaled; Abrehart, Nichola; Pritchard, Susan E; Al Atwah, Salem; Gowland, Penny A; Garnett, Martin C; Amidon, Gregory E; Spiller, Robin C; Amidon, Gordon L; Marciani, Luca

2017-08-07

The rate and extent of drug dissolution and absorption from solid oral dosage forms is highly dependent on the volume of liquid in the gastrointestinal tract (GIT). However, little is known about the time course of GIT liquid volumes after drinking a glass of water (8 oz), particularly in the colon, which is a targeted site for both locally and systemically acting drug products. Previous magnetic resonance imaging (MRI) studies offered novel insights on GIT liquid distribution in fasted humans in the stomach and small intestine, and showed that freely mobile liquid in the intestine collects in fairly distinct regions or "pockets". Based on this previous pilot data, we hypothesized that (1) it is possible to quantify the time course of the volume and number of liquid pockets in the undisturbed colon of fasted healthy humans following ingestion of 240 mL, using noninvasive MRI methods; (2) the amount of freely mobile water in the fasted human colon is of the order of only a few milliliters. Twelve healthy volunteers fasted overnight and underwent fasted abdominal MRI scans before drinking 240 mL (∼8 fluid ounces) of water. After ingesting the water they were scanned at frequent intervals for 2 h. The images were processed to quantify freely mobile water in the total and regional colon: ascending, transverse, and descending. The fasted colon contained (mean ± SEM) 11 ± 5 pockets of resting liquid with a total volume of 2 ± 1 mL (average). The colonic fluid peaked at 7 ± 4 mL 30 min after the water drink. This peak fluid was distributed in 17 ± 7 separate liquid pockets in the colon. The regional analysis showed that pockets of free fluid were found primarily in the ascending colon. The interindividual variability was very high; the subjects showed a range of number of colonic fluid pockets from 0 to 89 and total colonic freely mobile fluid volume from 0 to 49 mL. This is the first study measuring the time course of the number, regional location, and volume of pockets of freely mobile liquid in the undisturbed colon of fasted humans after ingestion of a glass of water. Novel insights into the colonic fluid environment will be particularly relevant to improve our understanding and design of the in vivo performance of controlled release formulations targeted to the colon. The in vivo quantitative information presented here can be input into physiologically based mechanistic models of dissolution and absorption, and can be used in the design and set up of novel in vitro performance tools predictive of the in vivo environment.

Changes in the temperature-dependent specific volume of supported polystyrene films with film thickness.

PubMed

Huang, Xinru; Roth, Connie B

2016-06-21

Recent studies have measured or predicted thickness-dependent shifts in density or specific volume of polymer films as a possible means of understanding changes in the glass transition temperature Tg(h) with decreasing film thickness with some experimental works claiming unrealistically large (25%-30%) increases in film density with decreasing thickness. Here we use ellipsometry to measure the temperature-dependent index of refraction of polystyrene (PS) films supported on silicon and investigate the validity of the commonly used Lorentz-Lorenz equation for inferring changes in density or specific volume from very thin films. We find that the density (specific volume) of these supported PS films does not vary by more than ±0.4% of the bulk value for film thicknesses above 30 nm, and that the small variations we do observe are uncorrelated with any free volume explanation for the Tg(h) decrease exhibited by these films. We conclude that the derivation of the Lorentz-Lorenz equation becomes invalid for very thin films as the film thickness approaches ∼20 nm, and that reports of large density changes greater than ±1% of bulk for films thinner than this likely suffer from breakdown in the validity of this equation or in the difficulties associated with accurately measuring the index of refraction of such thin films. For larger film thicknesses, we do observed small variations in the effective specific volume of the films of 0.4 ± 0.2%, outside of our experimental error. These shifts occur simultaneously in both the liquid and glassy regimes uniformly together starting at film thicknesses less than ∼120 nm but appear to be uncorrelated with Tg(h) decreases; possible causes for these variations are discussed.

Regulation of human airway surface liquid.

PubMed

Widdicombe, J H; Widdicombe, J G

1995-01-01

Human airways are lined with a film of liquid from 5-100 microns in depth, consisting of a periciliary sol around and a mucous gel above the cilia. Microscopical studies have shown the sol to be invariably the same depth as the length of the cilia, and we discuss possible reasons for this. The composition and sources of the airway surface liquid are also described. In addition the forces regulating its volume are analyzed. Several airway diseases are characterised by dramatic changes in the volume and composition of airway liquid. We review recent research suggesting that the accumulation of airway mucous secretions in cystic fibrosis is caused by alterations in active transport of ions and water across both the surface and gland epithelia.

Arctic Outflow West of Greenland: Mass and Freshwater Fluxes at Davis Strait

NASA Astrophysics Data System (ADS)

Lee, Craig; Curry, Beth; Petrie, Brian; Azetsu-Scott, Kumiko; Gobat, Jason

2014-05-01

Eberhard Fahrbach worked to understand the communication between the Arctic and subpolar oceans and its role in modulating Arctic change. This included long-standing leadership in the Arctic-Subarctic Ocean Flux program and the long-term quantification of fluxes east of Greenland, through Fram Strait, the primary pathway for Atlantic water passing into the Arctic and one of two gateways for freshwater flowing out. Freshwater also exits the Arctic west of Greenland, though the Canadian Arctic Archipelago and, to the south, Davis Strait. The strait provides a convenient choke point for monitoring temporal and spatial variability of Arctic outflow while also characterizing a critical upstream boundary condition for Labrador Sea convection. Fluxes through the Strait represent the net integrated Canadian Archipelago throughflow, over 50% of the Arctic's liquid freshwater discharge, modified by terrestrial inputs and oceanic processes during its southward transit through Baffin Bay. By the time they reach Davis Strait, Arctic waters already embody most of the transformations they undergo prior to exerting their influence on the deepwater formation sites in the Labrador Sea. An ongoing program has characterized Davis Strait volume, freshwater and heat flux since September 2004. Measurements include continuous velocity, temperature and salinity time series collected by a moored array, autumn ship-based hydrographic sections and high-resolution sections occupied by autonomous gliders. Moored instrumentation includes novel new instruments that provide temperature and salinity measurements in the critical region neat the ice-ocean interface and measurements over the shallow Baffin and West Greenland shelves, while gliders have captured the first high-resolution wintertime sections across the Strait. These data show large interannual variability in volume and freshwater transport, with no clear trends observed between 2004-2010. Average volume, liquid freshwater and sea ice transports are -1.6 +- 0.2 Sv, -93 +- 6 mSv and -10 +- 1 mSv, respectively (negative indicates southward transport). However, changes in circulation have occurred, as freshwater outflow from Baffin Bay has decreased and warm, salty North Atlantic inflow has increased since 1987-90. Local atmospheric variability within Baffin Bay and the Labrador Sea influence the observed variability in Davis Strait volume transport either directly or indirectly. Large-scale atmospheric teleconnections, such as the AO and NAO, correlate poorly with Davis Strait volume transport and are likely only an indicator of transport variability when the indices are strong.

Modified free volume theory of self-diffusion and molecular theory of shear viscosity of liquid carbon dioxide.

PubMed

Nasrabad, Afshin Eskandari; Laghaei, Rozita; Eu, Byung Chan

2005-04-28

In previous work on the density fluctuation theory of transport coefficients of liquids, it was necessary to use empirical self-diffusion coefficients to calculate the transport coefficients (e.g., shear viscosity of carbon dioxide). In this work, the necessity of empirical input of the self-diffusion coefficients in the calculation of shear viscosity is removed, and the theory is thus made a self-contained molecular theory of transport coefficients of liquids, albeit it contains an empirical parameter in the subcritical regime. The required self-diffusion coefficients of liquid carbon dioxide are calculated by using the modified free volume theory for which the generic van der Waals equation of state and Monte Carlo simulations are combined to accurately compute the mean free volume by means of statistical mechanics. They have been computed as a function of density along four different isotherms and isobars. A Lennard-Jones site-site interaction potential was used to model the molecular carbon dioxide interaction. The density and temperature dependence of the theoretical self-diffusion coefficients are shown to be in excellent agreement with experimental data when the minimum critical free volume is identified with the molecular volume. The self-diffusion coefficients thus computed are then used to compute the density and temperature dependence of the shear viscosity of liquid carbon dioxide by employing the density fluctuation theory formula for shear viscosity as reported in an earlier paper (J. Chem. Phys. 2000, 112, 7118). The theoretical shear viscosity is shown to be robust and yields excellent density and temperature dependence for carbon dioxide. The pair correlation function appearing in the theory has been computed by Monte Carlo simulations.

An approach to enhance self-compensation capability in paper-based devices for chemical sensing.

PubMed

Lo, Shih-Jie; Chen, Kuan-Hung; Yao, Da-Jeng

2015-12-01

This paper describes a simple design for increasing the tolerance of reagent dislocation on a paper-based platform using a combination of wax-treated paper and a vortex mixer. To date, massive budgetary funds are required in the biotechnological industry to develop new applications; a large part of that cost is attributable to the screening of specific chemical compounds. Here, we propose using a liquid-handling robot to automatically deposit selected reagents on a paper-based platform. We also present a preliminary concept approach for developing a reagent placing device with simple and inexpensive features. A defect of inaccuracy was observed between droplet location and test well location after viewing the performance of the liquid-handling robot on our paper-based platform. Because of dislocation error resulting from robotic reagent placement, we decided to apply an external, rotational force following droplet placement in order to compensate for the distance of reagent dislocation. Note, the largest distance of reagent dislocation was determined by examining the results of altering applied reagent volume, but not concentration, in volumes from 5 µL to 30 µL in a series of experiments. As a result of these experiments, we observed that dislocation was positively affected by an increase in applied volume. A colorimetric assay for nitrite detection was also performed to confirm the feasibility of this method. This work, we believe, can minimize the cost of chemical compound screening for the biotechnological industry. Copyright © 2015 Elsevier B.V. All rights reserved.

Pseudolinear gradient ultrahigh-pressure liquid chromatography using an injection valve assembly.

PubMed

Xiang, Yanqiao; Liu, Yansheng; Stearns, Stanley D; Plistil, Alex; Brisbin, Martin P; Lee, Milton L

2006-02-01

The use of ultrahigh pressures in liquid chromatography (UHPLC) imposes stringent requirements on hardware such as pumps, valves, injectors, connecting tubing, and columns. One of the most difficult components of the UHPLC system to develop has been the sample injector. Static-split injection, which can be performed at pressures up to 6900 bar (100,000 psi), consumes a large sample volume and is very irreproducible. A pressure-balanced injection valve provided better reproducibility, shorter injection time, reduced sample consumption, and greater ease of use; however, it could only withstand pressures up to approximately 1000 bar (15,000 psi). In this study, a new injection valve assembly that can operate at pressures as high as 2070 bar (30,000 psi) was evaluated for UHPLC. This assembly contains six miniature electronically controlled needle valves to provide accurate and precise volumes for introduction into the capillary LC column. It was found that sample volumes as small as several tenths of a nanoliter can be injected, which are comparable to the results obtained from the static-split injector. The reproducibilities of retention time, efficiency, and peak area were investigated, and the results showed that the relative standard deviations of these parameters were small enough for quantitative analyses. Separation experiments using the UHPLC system with this new injection valve assembly showed that this new injector is suitable for both isocratic and gradient operation modes. A newly designed capillary connector was used at a pressure as high as 2070 bar (30,000 psi).

Electrohydrodynamically driven large-area liquid ion sources

DOEpatents

Pregenzer, Arian L.

1988-01-01

A large-area liquid ion source comprises means for generating, over a large area of the surface of a liquid, an electric field of a strength sufficient to induce emission of ions from a large area of said liquid. Large areas in this context are those distinct from emitting areas in unidimensional emitters.

Salting-out homogenous extraction followed by ionic liquid/ionic liquid liquid-liquid micro-extraction for determination of sulfonamides in blood by high performance liquid chromatography.

PubMed

Liu, Zhongling; Yu, Wei; Zhang, Hanqi; Gu, Fanbin; Jin, Xiangqun

2016-12-01

Salting-out homogenous extraction followed by ionic liquid/ionic liquid dispersive liquid-liquid micro-extraction system was developed and applied to the extraction of sulfonamides in blood. High-performance liquid chromatography was applied to the determination of the analytes. The blood sample was centrifuged to obtain the serum. After the proteins in the serum were removed in the presence of acetonitrile, ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate, dipotassium hydrogen phosphate, ionic liquid 1-Hexyl-3-methylimidazolium hexafluorophosphate were added into the resulting solution. After the resulting mixture was ultrasonically shaken and centrifuged, the precipitate was separated. The acetonitrile was added in the precipitate and the analytes were extracted into the acetonitrile phase. The parameters affecting the extraction efficiency, such as volume of ionic liquid, amount of dipotassium hydrogen phosphate, volume of dispersant, extraction time and temperature were investigated. The limits of detection of sulfamethizole (STZ), sulfachlorpyridazine (SCP), sulfamethoxazole (SMX) and Sulfisoxazole (SSZ) were 4.78, 3.99, 5.21 and 3.77μgL -1 , respectively. When the present method was applied to the analysis of real blood samples, the recoveries of analytes ranged from 90.0% to 113.0% and relative standard deviations were lower than 7.2%. Copyright © 2016 Elsevier B.V. All rights reserved.

Ultrafast, sensitive and large-volume on-chip real-time PCR for the molecular diagnosis of bacterial and viral infections.

PubMed

Houssin, Timothée; Cramer, Jérémy; Grojsman, Rébecca; Bellahsene, Lyes; Colas, Guillaume; Moulet, Hélène; Minnella, Walter; Pannetier, Christophe; Leberre, Maël; Plecis, Adrien; Chen, Yong

2016-04-21

To control future infectious disease outbreaks, like the 2014 Ebola epidemic, it is necessary to develop ultrafast molecular assays enabling rapid and sensitive diagnoses. To that end, several ultrafast real-time PCR systems have been previously developed, but they present issues that hinder their wide adoption, notably regarding their sensitivity and detection volume. An ultrafast, sensitive and large-volume real-time PCR system based on microfluidic thermalization is presented herein. The method is based on the circulation of pre-heated liquids in a microfluidic chip that thermalize the PCR chamber by diffusion and ultrafast flow switches. The system can achieve up to 30 real-time PCR cycles in around 2 minutes, which makes it the fastest PCR thermalization system for regular sample volume to the best of our knowledge. After biochemical optimization, anthrax and Ebola simulating agents could be respectively detected by a real-time PCR in 7 minutes and a reverse transcription real-time PCR in 7.5 minutes. These detections are respectively 6.4 and 7.2 times faster than with an off-the-shelf apparatus, while conserving real-time PCR sample volume, efficiency, selectivity and sensitivity. The high-speed thermalization also enabled us to perform sharp melting curve analyses in only 20 s and to discriminate amplicons of different lengths by rapid real-time PCR. This real-time PCR microfluidic thermalization system is cost-effective, versatile and can be then further developed for point-of-care, multiplexed, ultrafast and highly sensitive molecular diagnoses of bacterial and viral diseases.

Refractive index of liquid mixtures: theory and experiment.

PubMed

Reis, João Carlos R; Lampreia, Isabel M S; Santos, Angela F S; Moita, Maria Luísa C J; Douhéret, Gérard

2010-12-03

An innovative approach is presented to interpret the refractive index of binary liquid mixtures. The concept of refractive index "before mixing" is introduced and shown to be given by the volume-fraction mixing rule of the pure-component refractive indices (Arago-Biot formula). The refractive index of thermodynamically ideal liquid mixtures is demonstrated to be given by the volume-fraction mixing rule of the pure-component squared refractive indices (Newton formula). This theoretical formulation entails a positive change of refractive index upon ideal mixing, which is interpreted in terms of dissimilar London dispersion forces centred in the dissimilar molecules making up the mixture. For real liquid mixtures, the refractive index of mixing and the excess refractive index are introduced in a thermodynamic manner. Examples of mixtures are cited for which excess refractive indices and excess molar volumes show all of the four possible sign combinations, a fact that jeopardises the finding of a general equation linking these two excess properties. Refractive indices of 69 mixtures of water with the amphiphile (R,S)-1-propoxypropan-2-ol are reported at five temperatures in the range 283-303 K. The ideal and real refractive properties of this binary system are discussed. Pear-shaped plots of excess refractive indices against excess molar volumes show that extreme positive values of excess refractive index occur at a substantially lower mole fraction of the amphiphile than extreme negative values of excess molar volume. Analysis of these plots provides insights into the mixing schemes that occur in different composition segments. A nearly linear variation is found when Balankina's ratios between excess and ideal values of refractive indices are plotted against ratios between excess and ideal values of molar volumes. It is concluded that, when coupled with volumetric properties, the new thermodynamic functions defined for the analysis of refractive indices of liquid mixtures give important complementary information on the mixing process over the whole composition range.

Pollenkitt wetting mechanism enables species-specific tunable pollen adhesion.

PubMed

Lin, Haisheng; Gomez, Ismael; Meredith, J Carson

2013-03-05

Plant pollens are microscopic particles exhibiting a remarkable breadth of complex solid surface features. In addition, many pollen grains are coated with a viscous liquid, "pollenkitt", thought to play important roles in pollen dispersion and adhesion. However, there exist no quantitative studies of the effects of solid surface features or pollenkitt on adhesion of pollen grains, and it remains unclear what role these features play in pollen adhesion and transport. We report AFM adhesion measurements of five pollen species with a series of test surfaces in which each pollen has a unique solid surface morphology and pollenkitt volume. The results indicate that the combination of surface morphology (size and shape of echinate or reticulate features) with the pollenkitt volume provides pollens with a remarkably tunable adhesion to surfaces. With pollenkitt removed, pollen grains had relatively low adhesion strengths that were independent of surface chemistry and scalable with the tip radius of the pollen's ornamentation features, according to the Hamaker model. With the pollenkitt intact, adhesion was up to 3-6 times higher than the dry grains and exhibited strong substrate dependence. The adhesion enhancing effect of pollenkitt was driven by the formation of pollenkitt capillary bridges and was surprisingly species-dependent, with echinate insect-pollinated species (dandelion and sunflower) showing significantly stronger adhesion and higher substrate dependence than wind-pollinated species (ragweed, poplar, and olive). The combination of high pollenkitt volume and large convex, spiny surface features in echinate entomophilous varieties appears to enhance the spreading area of the liquid pollenkitt relative to varieties of pollen with less pollenkitt volume and less pronounced surface features. Measurements of pollenkitt surface energy indicate that the adhesive strength of capillary bridges is primarily dependent on nonpolar van der Waals interactions, with some contribution from the Lewis basic component of surface energy.

Two-phase mixed media dielectric with macro dielectric beads for enhancing resistivity and breakdown strength

DOEpatents

Falabella, Steven; Meyer, Glenn A; Tang, Vincent; Guethlein, Gary

2014-06-10

A two-phase mixed media insulator having a dielectric fluid filling the interstices between macro-sized dielectric beads packed into a confined volume, so that the packed dielectric beads inhibit electro-hydrodynamically driven current flows of the dielectric liquid and thereby increase the resistivity and breakdown strength of the two-phase insulator over the dielectric liquid alone. In addition, an electrical apparatus incorporates the two-phase mixed media insulator to insulate between electrical components of different electrical potentials. And a method of electrically insulating between electrical components of different electrical potentials fills a confined volume between the electrical components with the two-phase dielectric composite, so that the macro dielectric beads are packed in the confined volume and interstices formed between the macro dielectric beads are filled with the dielectric liquid.

Cavities in molecular liquids and the theory of hydrophobic solubilities

NASA Technical Reports Server (NTRS)

Pohorille, A.; Pratt, L. R.; MacElroy, R. (Principal Investigator)

1990-01-01

Thermal configurational data on neat liquids are used to obtain the work of formation of hard spherical cavities of atomic size in six molecular solvents: n-hexane, n-dodecane, n-undecyl alcohol, chloroform, carbon tetrachloride, and water. These results are used to test a recent suggestion that the differences between nonaqueous solvents and liquid water in solvation of inert gases are not principally due to the hydrogen-bonded structure of liquid water but rather to the comparatively small size of the water molecule. The frequencies of occurrence of cavities in liquid water can be meaningfully distinguished from those in the organic solvents. Liquid water has a larger fractional free volume, but that free volume is distributed in smaller packets. With respect to cavity work, water is compared to a solvent of the same molecular density and composed of hard spheres of the same size as the water molecule. That comparison indicates that the hard-sphere liquid finds more ways to configure its free volume in order to accommodate an atomic solute of substantial size and thus, would be more favorable solvent for inert gases. The scaled particle model of inert gas solubility in liquid water predicts cavity works 20% below the numerical data for TIP4P water at 300 K and 1.0 g/cm3 for cavity radii near 2.0 angstroms. It is argued that the sign of this difference is just the sign that ought to be expected and that the magnitude of this difference measures structural differences between water and the directly comparable hard-sphere liquid. In conjunction with previous data, these results indicate that atomic sized cavities should be considered submacroscopic.

Gauging Systems Monitor Cryogenic Liquids

NASA Technical Reports Server (NTRS)

2009-01-01

Rocket fuel needs to stay cool - super cool, in fact. The ability to store gas propellants like liquid hydrogen and oxygen at cryogenic temperatures (below -243 F) is crucial for space missions in order to reduce their volumes and allow their storage in smaller (and therefore, less costly) tanks. The Agency has used these cryogenic fluids for vehicle propellants, reactants, and life support systems since 1962 with the Centaur upper stage rocket, which was powered with liquid oxygen and liquid hydrogen. During proposed long-duration missions, super-cooled fluids will also be used in space power systems, spaceports, and lunar habitation systems. In the next generation of launch vehicles, gaseous propellants will be cooled to and stored for extended periods at even colder temperatures than currently employed via a process called densification. Densification sub-cools liquids to temperatures even closer to absolute zero (-459 F), increasing the fluid s density and shrinking its volume beyond common cryogenics. Sub-cooling cryogenic liquid hydrogen, for instance, from 20 K (-423 F) to 15 K (-432.4 F) reduces its mass by 10 percent. These densified liquid gases can provide more cost savings from reduced payload volume. In order to benefit from this cost savings, the Agency is working with private industry to prevent evaporation, leakage, and other inadvertent loss of liquids and gases in payloads - requiring new cryogenic systems to prevent 98 percent (or more) of boil-off loss. Boil-off occurs when cryogenic or densified liquids evaporate, and is a concern during launch pad holds. Accurate sensing of propellants aboard space vehicles is also critical for proper engine shutdown and re-ignition after launch, and zero boil-off fuel systems are also in development for the Altair lunar lander.

Estimation of liquid volume fraction using ultrasound transit time spectroscopy

NASA Astrophysics Data System (ADS)

Al-Qahtani, Saeed M.; Langton, Christian M.

2016-12-01

It has recently been proposed that the propagation of an ultrasound wave through complex structures, consisting of two-materials of differing ultrasound velocity, may be considered as an array of parallel ‘sonic rays’, the transit time of each determined by their relative proportion; being a minimum (t min) in entire higher velocity material, and a maximum (t max) in entire lower velocity material. An ultrasound transit time spectrum (UTTS) describes the proportion of sonic rays at an individual transit time. It has previously been demonstrated that the solid volume fraction of a solid:liquid composite, specifically acrylic step-wedges immersed in water, may be reliably estimated from the UTTS. The aim of this research was to investigate the hypothesis that the volume fraction of a two-component liquid mixture, of unequal ultrasound velocity, may also be estimated by UTTS. A through-transmission technique incorporating two 1 MHz ultrasound transducers within a horizontally-aligned cylindrical tube-housing was utilised, the proportion of silicone oil to water being varied from 0% to 100%. The liquid volume fraction was estimated from the UTTS at each composition, the coefficient of determination (R 2%) being 98.9  ±  0.7%. The analysis incorporated a novel signal amplitude normalisation technique to compensate for absorption within the silicone oil. It is therefore envisaged that the parallel sonic ray concept and the derived UTTS may be further applied to the quantification of liquid mixture composition assessment.

Ionic liquid-based dispersive liquid-liquid microextraction with back-extraction coupled with capillary electrophoresis to determine phenolic compounds.

PubMed

Zhou, Caihong; Tong, Shanshan; Chang, Yunxia; Jia, Qiong; Zhou, Weihong

2012-04-01

Ionic liquid (IL) based dispersive liquid-liquid microextraction (DLLME) with back-extraction coupled with capillary electrophoresis ultraviolet detection was developed to determine four phenolic compounds (bisphenol-A, β-naphthol, α-naphthol, 2, 4-dichlorophenol) in aqueous cosmetics. The developed method was used to preconcentrate and clean up the four phenolic compounds including two steps. The analytes were transferred into room temperature ionic liquid (1-octyl-3-methylimidazolium hexafluorophosphate, [C(8) MIM][PF(6) ]) rich-phase in the first step. In the second step, the analytes were back-extracted into the alkaline aqueous phase. The effects of extraction parameters, such as type and volume of extraction solvent, type and volume of disperser, extraction and centrifugal time, sample pH, salt addition, and concentration and volume of NaOH in back-extraction were investigated. Under the optimal experimental conditions, the preconcentration factors were 60.1 for bisphenol-A, 52.7 for β-naphthol, 49.2 for α-naphthol, and 18.0 for 2, 4-dichlorophenol. The limits of detection for bisphenol-A, β-naphthol, α-naphthol and 2, 4-dichlorophenol were 5, 5, 8, and 100 ng mL(-1), respectively. Four kinds of aqueous cosmetics including toner, soften lotion, make-up remover, and perfume were analyzed and yielded recoveries ranging from 81.6% to 119.4%. The main advantages of the proposed method are quick, easy, cheap, and effective. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Coarsening in Solid-Liquid Mixtures Studied on the Space Shuttle

NASA Technical Reports Server (NTRS)

Caruso, John J.

1999-01-01

Ostwald ripening, or coarsening, is a process in which large particles in a two-phase mixture grow at the expense of small particles. It is a ubiquitous natural phenomena occurring in the late stages of virtually all phase separation processes. In addition, a large number of commercially important alloys undergo coarsening because they are composed of particles embedded in a matrix. Many of them, such as high-temperature superalloys used for turbine blade materials and low-temperature aluminum alloys, coarsen in the solid state. In addition, many alloys, such as the tungsten-heavy metal systems, coarsen in the solid-liquid state during liquid phase sintering. Numerous theories have been proposed that predict the rate at which the coarsening process occurs and the shape of the particle size distribution. Unfortunately, these theories have never been tested using a system that satisfies all the assumptions of the theory. In an effort to test these theories, NASA studied the coarsening process in a solid-liquid mixture composed of solid tin particles in a liquid lead-tin matrix. On Earth, the solid tin particles float to the surface of the sample, like ice in water. In contrast, in a microgravity environment this does not occur. The microstructures in the ground- and space-processed samples (see the photos) show clearly the effects of gravity on the coarsening process. The STS-83-processed sample (right image) shows nearly spherical uniformly dispersed solid tin particles. In contrast, the identically processed, ground-based sample (left image) shows significant density-driven, nonspherical particles, and because of the higher effective solid volume fraction, a larger particle size after the same coarsening time. The "Coarsening in Solid-Liquid Mixtures" (CSLM) experiment was conducted in the Middeck Glovebox facility (MGBX) flown aboard the shuttle in the Microgravity Science Laboratory (MSL-1/1R) on STS-83/94. The primary objective of CSLM is to measure the temporal evolution of the solid particles during coarsening.

Venusian pancake domes: Insights from terrestrial voluminous silicic lavas and thermal modeling

NASA Technical Reports Server (NTRS)

Manley, Curtis R.

1993-01-01

The so-called 'pancake' domes, and several other volcanoes on Venus, appear to represent large extrusions of silicic lava. Similar voluminous rhyolite lava flows, often associated with mantle plumes, are known on Earth. Venus' high ambient temperature, and insulation by the dome's brecciated carapace, both act to prolong cooling of a dome's interior, allowing for episodic lava input over an extended period of time. Field relations and aspect ratios of terrestrial voluminous rhyolite lavas imply continuous, non-episodic growth, reflecting tapping of a large volume of dry, anatectic silicic magma. Petrogenetically, the venusian domes may be analogous to chains of small domes on Earth, which represent 'leakage' of evolved material from magma bodies fractionating from much more mafic liquids.

A regional analysis of cloudy mean spherical albedo over the marine stratocumulus region and the tropical Atlantic Ocean. M.S. Thesis

NASA Technical Reports Server (NTRS)

Ginger, Kathryn M.

1993-01-01

Since clouds are the largest variable in Earth's radiation budget, it is critical to determine both the spatial and temporal characteristics of their radiative properties. The relationships between cloud properties and cloud fraction are studied in order to supplement grid scale parameterizations. The satellite data used is from three hourly ISCCP (International Satellite Cloud Climatology Project) and monthly ERBE (Earth Radiation Budget Experiment) data on a 2.5 deg x 2.5 deg latitude-longitude grid. Mean cloud spherical albedo, the mean optical depth distribution, and cloud fraction are examined and compared off the coast of California and the mid-tropical Atlantic for July 1987 and 1988. Individual grid boxes and spatial averages over several grid boxes are correlated to Coakley's theory of reflection for uniform and broken layered cloud and to Kedem, et al.'s findings that rainfall volume and fractional area of rain in convective systems is linear. Kedem's hypothesis can be expressed in terms of cloud properties. That is, the total volume of liquid in a box is a linear function of cloud fraction. Results for the marine stratocumulus regime indicate that albedo is often invariant for cloud fractions of 20% to 80%. Coakley's satellite model of small and large clouds with cores (1 km) and edges (100 m) is consistent with this observation. The cores maintain high liquid water concentrations and large droplets while the edges contain low liquid water concentrations and small droplets. Large clouds are just a collection of cores. The mean optical depth (TAU) distributions support the above observation with TAU values of 3.55 to 9.38 favored across all cloud fractions. From these results, a method based upon Kedem, et al's theory is proposed to separate the cloud fraction and liquid water path (LWP) calculations in a general circulation model (GCM). In terms of spatial averaging, a linear relationship between albedo and cloud fraction is observed. For tropical locations outside the Intertropical Convergence Zone (ITCZ), results of cloud fraction and albedo spatial averaging followed that of the stratus boxes containing few overcast scenes. Both the ideas of Coakley and Kedem, et al. apply. Within the ITCZ, the grid boxes tended to have the same statistical properties as stratus boxes containing many overcast scenes. Because different dynamical forcing mechanisms are present, it is difficult to devise a method for determining subgrid scale variations. Neither of the theories proposed by Kedem, et al. or Coakley works well for the boxes with numerous overcast scenes.

A Regional Analysis of Cloudy Mean Spherical Albedo over the Marine Stratocumulus Region and the Tropical Atlantic Ocean

NASA Technical Reports Server (NTRS)

Ginger, Kathryn M.

1993-01-01

Since clouds are the largest variable in Earth's radiation budget, it is critical to determine both the spatial and temporal characteristics of their radiative properties. This study examines the relationships between cloud properties and cloud fraction in order to supplement grid scale parameterizations. The satellite data used in this study is from three hourly ISCCP (International Satellite Cloud Climatology Project) and monthly ERBE (Earth Radiation Budget Experiment) data on a 2.50 x 2.50 latitude-longitude grid. Mean cloud spherical albedo, the mean optical depth distribution and cloud fraction are examined and compared off the coast of California and the mid-tropical Atlantic for July 1987 and 1988. Individual grid boxes and spatial averages over several grid boxes are correlated to Coakleys (1991) theory of reflection for uniform and broken layered cloud and to Kedem, et al.(1990) findings that rainfall volume and fractional area of rain in convective systems is linear. Kedem's hypothesis can be expressed in terms of cloud properties. That is, the total volume of liquid in a box is a linear function of cloud fraction. Results for the marine stratocumulus regime indicate that albedo is often invariant for cloud fractions of 20% to 80%. Coakley's satellite model of small and large clouds with cores (1 km) and edges (100 in) is consistent with this observation. The cores maintain high liquid water concentrations and large droplets while the edges contain low liquid water concentrations and small droplets. Large clouds are just a collection of cores. The mean optical depth (TAU) distributions support the above observation with TAU values of 3.55 to 9.38 favored across all cloud fractions. From these results, a method based upon Kedem, et al. theory is proposed to separate the cloud fraction and liquid water path (LWP) calculations in a general circulation model (GCM). In terms of spatial averaging, a linear relationship between albedo and cloud fraction is observed. For tropical locations outside the Intertropical Convergence Zone (ITCZ), results of cloud fraction and albedo spatial averaging followed that of the stratus boxes containing few overcast scenes. Both the ideas of Coakley and Kedem, et al. apply. Within the ITCZ, the grid boxes tended to have the same statistical properties as stratus boxes containing many overcast scenes. Because different dynamical forcing mechanisms are present, it is difficult to devise a method for determining subgrid scale variations. Neither of the theories proposed by Kedem, et al. or Coakley works well for the boxes with numerous overcast scenes.

SU-E-I-79: Source Geometry Dependence of Gamma Well-Counter Measurements

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

Park, M; Belanger, A; Kijewski, M

Purpose: To determine the effect of liquid sample volume and geometry on counting efficiency in a gamma well-counter, and to assess the relative contributions of sample geometry and self-attenuation. Gamma wellcounters are standard equipment in clinical and preclinical studies, for measuring patient blood radioactivity and quantifying animal tissue uptake for tracer development and other purposes. Accurate measurements are crucial. Methods: Count rates were measured for aqueous solutions of 99m- Tc at four liquid volume values in a 1-cm-diam tube and at six volume values in a 2.2-cm-diam vial. Total activity was constant for all volumes, and data were corrected formore » decay. Count rates from a point source in air, supported by a filter paper, were measured at seven heights between 1.3 and 5.7 cm from the bottom of a tube. Results: Sample volume effects were larger for the tube than for the vial. For the tube, count efficiency relative to a 1-cc volume ranged from 1.05 at 0.05 cc to 0.84 at 3 cc. For the vial, relative count efficiency ranged from 1.02 at 0.05 cc to 0.87 at 15 cc. For the point source, count efficiency relative to 1.3 cm from the tube bottom ranged from 0.98 at 1.8 cm to 0.34 at 5.7 cm. The relative efficiency of a 3-cc liquid sample in a tube compared to a 1-cc sample is 0.84; the average relative efficiency for the solid sample in air between heights in the tube corresponding to the surfaces of those volumes (1.3 and 4.8 cm) is 0.81, implying that the major contribution to efficiency loss is geometry, rather than attenuation. Conclusion: Volume-dependent correction factors should be used for accurate quantitation radioactive of liquid samples. Solid samples should be positioned at the bottom of the tube for maximum count efficiency.« less

Beer tapping: dynamics of bubbles after impact

NASA Astrophysics Data System (ADS)

Mantič-Lugo, V.; Cayron, A.; Brun, P.-T.; Gallaire, F.

2015-12-01

Beer tapping is a well known prank where a bottle of beer is impacted from the top by a solid object, usually another bottle, leading to a sudden foam overflow. A description of the shock-driven bubble dynamics leading to foaming is presented based on an experimental and numerical study evoking the following physical picture. First, the solid impact produces a sudden downwards acceleration of the bottle creating a strong depression in the liquid bulk. The existing bubbles undergo a strong expansion and a sudden contraction ending in their collapse and fragmentation into a large amount of small bubbles. Second, the bubble clouds present a large surface area to volume ratio, enhancing the CO2 diffusion from the supersaturated liquid, hence growing rapidly and depleting the CO2. The clouds of bubbles migrate upwards in the form of plumes pulling the surrounding liquid with them and eventually resulting in the foam overflow. The sudden pressure drop that triggers the bubble dynamics with a collapse and oscillations is modelled by the Rayleigh-Plesset equation. The bubble dynamics from impact to collapse occurs over a time (tb ≃ 800 μs) much larger than the acoustic time scale of the liquid bulk (tac = 2H/c ≃ 80 μs), for the experimental container of height H = 6 cm and a speed of sound around c ≃ 1500 m/s. This scale separation, together with the comparison of numerical and experimental results, suggests that the pressure drop is controlled by two parameters: the acceleration of the container and the distance from the bubble to the free surface.

Impact of ultrasound on solid-liquid extraction of phenolic compounds from maritime pine sawdust waste. Kinetics, optimization and large scale experiments.

PubMed

Meullemiestre, A; Petitcolas, E; Maache-Rezzoug, Z; Chemat, F; Rezzoug, S A

2016-01-01

Maritime pine sawdust, a by-product from industry of wood transformation, has been investigated as a potential source of polyphenols which were extracted by ultrasound-assisted maceration (UAM). UAM was optimized for enhancing extraction efficiency of polyphenols and reducing time-consuming. In a first time, a preliminary study was carried out to optimize the solid/liquid ratio (6g of dry material per mL) and the particle size (0.26 cm(2)) by conventional maceration (CVM). Under these conditions, the optimum conditions for polyphenols extraction by UAM, obtained by response surface methodology, were 0.67 W/cm(2) for the ultrasonic intensity (UI), 40°C for the processing temperature (T) and 43 min for the sonication time (t). UAM was compared with CVM, the results showed that the quantity of polyphenols was improved by 40% (342.4 and 233.5mg of catechin equivalent per 100g of dry basis, respectively for UAM and CVM). A multistage cross-current extraction procedure allowed evaluating the real impact of UAM on the solid-liquid extraction enhancement. The potential industrialization of this procedure was implemented through a transition from a lab sonicated reactor (3 L) to a large scale one with 30 L volume. Copyright © 2015 Elsevier B.V. All rights reserved.

Solar neutrino detection in a large volume double-phase liquid argon experiment

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

Franco, D.; Agnes, P.; Giganti, C.

2016-08-01

Precision measurements of solar neutrinos emitted by specific nuclear reaction chains in the Sun are of great interest for developing an improved understanding of star formation and evolution. Given the expected neutrino fluxes and known detection reactions, such measurements require detectors capable of collecting neutrino-electron scattering data in exposures on the order of 1 ktonne-yr, with good energy resolution and extremely low background. Two-phase liquid argon time projection chambers (LAr TPCs) are under development for direct Dark Matter WIMP searches, which possess very large sensitive mass, high scintillation light yield, good energy resolution, and good spatial resolution in all threemore » cartesian directions. While enabling Dark Matter searches with sensitivity extending to the ''neutrino floor'' (given by the rate of nuclear recoil events from solar neutrino coherent scattering), such detectors could also enable precision measurements of solar neutrino fluxes using the neutrino-electron elastic scattering events. Modeling results are presented for the cosmogenic and radiogenic backgrounds affecting solar neutrino detection in a 300 tonne (100 tonne fiducial) LAr TPC operating at LNGS depth (3,800 meters of water equivalent). The results show that such a detector could measure the CNO neutrino rate with ∼15% precision, and significantly improve the precision of the {sup 7}Be and pep neutrino rates compared to the currently available results from the Borexino organic liquid scintillator detector.« less

Effect of interfacial turbulence and accommodation coefficient on CFD predictions of pressurization and pressure control in cryogenic storage tank

NASA Astrophysics Data System (ADS)

Kassemi, Mohammad; Kartuzova, Olga

2016-03-01

Pressurization and pressure control in cryogenic storage tanks are to a large extent affected by heat and mass transport across the liquid-vapor interface. These mechanisms are, in turn, controlled by the kinetics of the phase change process and the dynamics of the turbulent recirculating flows in the liquid and vapor phases. In this paper, the effects of accommodation coefficient and interfacial turbulence on tank pressurization and pressure control simulations are examined. Comparison between numerical predictions and ground-based measurements in two large liquid hydrogen tank experiments, performed in the K-site facility at NASA Glenn Research Center (GRC) and the Multi-purpose Hydrogen Test Bed (MHTB) facility at NASA Marshall Space Flight Center (MSFC), are used to show the impact of accommodation coefficient and interfacial and vapor phase turbulence on evolution of pressure and temperatures in the cryogenic storage tanks. In particular, the self-pressurization comparisons indicate that: (1) numerical predictions are essentially independent of the magnitude of the accommodation coefficient; and (2) surprisingly, laminar models sometimes provide results that are in better agreement with experimental self-pressurization rates, even in parametric ranges where the bulk flow is deemed fully turbulent. In this light, shortcomings of the present CFD models, especially, numerical treatments of interfacial mass transfer and turbulence, as coupled to the Volume-of-Fluid (VOF) interface capturing scheme, are underscored and discussed.

Optimization and determination of Cd (II) in different environmental water samples with dispersive liquid-liquid microextraction preconcentration combined with inductively coupled plasma optical emission spectrometry.

PubMed

Salahinejad, Maryam; Aflaki, Fereydoon

2011-06-01

Dispersive liquid-liquid microextraction followed by inductively coupled plasma-optical emission spectrometry has been investigated for determination of Cd(II) ions in water samples. Ammonium pyrrolidine dithiocarbamate was used as chelating agent. Several factors influencing the microextraction efficiency of Cd (II) ions such as extracting and dispersing solvent type and their volumes, pH, sample volume, and salting effect were optimized. The optimization was performed both via one variable at a time, and central composite design methods and the optimum conditions were selected. Both optimization methods showed nearly the same results: sample size 5 mL; dispersive solvent ethanol; dispersive solvent volume 2 mL; extracting solvent chloroform; extracting solvent volume 200 [Formula: see text]L; pH and salt amount do not affect significantly the microextraction efficiency. The limits of detection and quantification were 0.8 and 2.5 ng L( - 1), respectively. The relative standard deviation for five replicate measurements of 0.50 mg L( - 1) of Cd (II) was 4.4%. The recoveries for the spiked real samples from tap, mineral, river, dam, and sea waters samples ranged from 92.2% to 104.5%.

Mathematical and computational studies of the stability of axisymmetric annular capillary free surfaces

NASA Technical Reports Server (NTRS)

Albright, N.; Concus, P.; Karasalo, I.

1977-01-01

Of principal interest is the stability of a perfectly wetting liquid in an inverted, vertical, right circular-cylindrical container having a concave spheroidal bottom. The mathematical conditions that the contained liquid be in stable static equilibrium are derived, including those for the limiting case of zero contact angle. Based on these results, a computational investigation is carried out for a particular container that is used for the storage of liquid fuels in NASA Centaur space vehicles, for which the axial ratio of the container bottom is 0.724. It is found that for perfectly wetting liquids the qualitative nature of the onset of instability changes at a critical liquid volume, which for the Centaur fuel tank corresponds to a mean fill level of approximately 0.503 times the tank's radius. Small-amplitude periodic sloshing modes for this tank were calculated; oscillation frequencies or growth rates are given for several Bond numbers and liquid volumes, for normal modes having up to six angular nodes.

SINDA/FLUINT Stratified Tank Modeling for Cryrogenic Propellant Tanks

NASA Technical Reports Server (NTRS)

Sakowski, Barbara

2014-01-01

A general purpose SINDA/FLUINT (S/F) stratified tank model was created to simulate self-pressurization and axial jet TVS; Stratified layers in the vapor and liquid are modeled using S/F lumps.; The stratified tank model was constructed to permit incorporating the following additional features:, Multiple or singular lumps in the liquid and vapor regions of the tank, Real gases (also mixtures) and compressible liquids, Venting, pressurizing, and draining, Condensation and evaporation/boiling, Wall heat transfer, Elliptical, cylindrical, and spherical tank geometries; Extensive user logic is used to allow detailed tailoring - Don't have to rebuilt everything from scratch!!; Most code input for a specific case is done through the Registers Data Block:, Lump volumes are determined through user input:; Geometric tank dimensions (height, width, etc); Liquid level could be input as either a volume percentage of fill level or actual liquid level height

Metallurgical technologies, energy conversion, and magnetohydrodynamic flows

NASA Astrophysics Data System (ADS)

Branover, Herman; Unger, Yeshajahu

The present volume discusses metallurgical applications of MHD, R&D on MHD devices employing liquid working medium for process applications, electromagnetic (EM) modulation of molten metal flow, EM pump performance of superconducting MHD devices, induction EM alkali-metal pumps, a physical model for EM-driven flow in channel-induction furnaces, grain refinement in Al alloys via EM vibrational method, dendrite growth of solidifying metal in dc magnetic field, MHD for mass and heat transfer in single-crystal melt growth, inverse EM shaping, and liquid-metal MHD development in Israel. Also discussed are the embrittlement of steel by lead, an open cycle MHD disk generator, the acceleration of gas-liquid piston flows for molten-metal MHD generators, MHD flow around a cylinder, new MHD drag coefficients, liquid-metal MHD two-phase flow, and two-phase liquid gas mixers for MHD energy conversion. (No individual items are abstracted in this volume)

Capillary Pressure of a Liquid Between Uniform Spheres Arranged in a Square-Packed Layer

NASA Technical Reports Server (NTRS)

Alexader, J. Iwan D.; Slobozhanin, Lev A.; Collicott, Steven H.

2004-01-01

The capillary pressure in the pores defined by equidimensional close-packed spheres is analyzed numerically. In the absence of gravity the menisci shapes are constructed using Surface Evolver code. This permits calculation the free surface mean curvature and hence the capillary pressure. The dependences of capillary pressure on the liquid volume constructed here for a set of contact angles allow one to determine the evolution of basic capillary characteristics under quasi-static infiltration and drainage. The maximum pressure difference between liquid and gas required for a meniscus passing through a pore is calculated and compared with that for hexagonal packing and with approximate solution given by Mason and Morrow [l]. The lower and upper critical liquid volumes that determine the stability limits for the equilibrium capillary liquid in contact with square packed array of spheres are tabulated for a set of contact angles.

Development and Design of a Zero-G Liquid Quantity Gauge for a Solar Thermal Vehicle

NASA Technical Reports Server (NTRS)

Dodge, Franklin T.; Green, Steven T.; Petullo, Steven P.; VanDresar, Neil T.; Taylor, William J. (Technical Monitor)

2002-01-01

The development and design of a cryogenic liquid quantity gauge for zero-g applications is described. The gauge, named the Compression Mass Gauge (CMG), operates on the principle of slightly changing the volume of the tank by an oscillating bellows. The resulting pressure change is measured and used to predict the volume of vapor in the tank, from which the volume of liquid is computed. For each gauging instance, pressures are measured for several different bellows frequencies to enable minor real-gas effects to be quantified and thereby to obtain a gauging accuracy of +/- 1% of tank volume. Southwest Research Institute (Tm) and NASA-GRC (Glenn Research Center) have developed several previous breadboard and engineering development gauges and tested them in cryogenic hydrogen and nitrogen to establish the gauge capabilities, to resolve several design issues, and to formulate data processing algorithms. The CMG has been selected by NASA's Future X program for a flight demonstration on the USAF (United States Air Force) / Boeing Solar Thermal Vehicle Space Experiment (SOTVSE). This paper reviews the design trade studies needed to satisfy the SOTVSE limitations on CMG power, volume, and mass, and describes the mechanical design of the CMG.

Molecular Volumes and the Stokes-Einstein Equation

ERIC Educational Resources Information Center

Edward, John T.

1970-01-01

Examines the limitations of the Stokes-Einstein equation as it applies to small solute molecules. Discusses molecular volume determinations by atomic increments, molecular models, molar volumes of solids and liquids, and molal volumes. Presents an empirical correction factor for the equation which applies to molecular radii as small as 2 angstrom…

Synthesis and chromatographic characterization of dextran-coated zirconia high-performance liquid chromatographic stationary phases.

PubMed

Dunlap, C J; Carr, P W

1996-10-11

Porous zirconia particles made by the oil emulsion (OE) method and the polymerization-induced colloid aggregation (PICA) method have been coated with a small, carboxymethylated (approximately 5%) dextran polymer and crosslinked in place. The parameters of the coating process (dextran concentration, adsorption time and crosslinker concentration) have all been examined and an optimum value for each determined. The coated and uncoated materials were characterized by nitrogen sorptometry and size-exclusion chromatography (SEC) using solutes (polystyrenes and dextrans) of well-defined molecular masses. Nitrogen sorptometry results show that the PICA material has a much lower pore volume and smaller pore diameter than do the OE materials. Despite this, the elution volumes of the SEC probes change very little upon polymer coating the PICA material while the OE material shows a very large change upon coating.

Liquid nitrogen ingestion leading to massive pneumoperitoneum without identifiable gastrointestinal perforation.

PubMed

Walsh, Mike J; Tharratt, Steven R; Offerman, Steven R

2010-06-01

Liquid nitrogen (LN) ingestion is unusual, but may be encountered by poison centers, emergency physicians, and general surgeons. Unique properties of LN produce a characteristic pattern of injury. A 19-year-old male college student presented to the Emergency Department complaining of abdominal pain and "bloating" after drinking LN. His presentation vital signs were remarkable only for mild tachypnea and tachycardia. On physical examination, he had mild respiratory difficulty due to abdominal distention. His abdomen was tense and distended. Abdominal X-ray studies revealed a massive pneumoperitoneum. At laparotomy, he was found to have a large amount of peritoneal gas. No perforation was identified. After surgery, the patient made an uneventful recovery and was discharged 5 days later. At 2-week clinic follow-up, he was doing well without complications. Nitrogen is a colorless, odorless gas at room temperature. Due to its low boiling point (-195 degrees C), LN rapidly evaporates when in contact with body surface temperatures. Therefore, ingested LN causes damage by two mechanisms: rapid freezing injury upon mucosal contact and rapid volume expansion as nitrogen gas is formed. Patients who ingest LN may develop gastrointestinal perforation and massive pneumoperitoneum. Because rapid gas formation may allow large volumes to escape from tiny perforations, the exact site of perforation may never be identified. In cases of LN ingestion, mucosal injury and rapid gas formation can cause massive pneumoperitoneum. Although laparotomy is recommended for all patients with signs of perforation, the site of injury may never be identified. Copyright 2010 Elsevier Inc. All rights reserved.

Modeling of macrosegregation caused by volumetric deformation in a coherent mushy zone

NASA Astrophysics Data System (ADS)

Nicolli, Lilia C.; Mo, Asbjørn; M'hamdi, Mohammed

2005-02-01

A two-phase volume-averaged continuum model is presented that quantifies macrosegregation formation during solidification of metallic alloys caused by deformation of the dendritic network and associated melt flow in the coherent part of the mushy zone. Also, the macrosegregation formation associated with the solidification shrinkage (inverse segregation) is taken into account. Based on experimental evidence established elsewhere, volumetric viscoplastic deformation (densification/dilatation) of the coherent dendritic network is included in the model. While the thermomechanical model previously outlined (M. M’Hamdi, A. Mo, and C.L. Martin: Metall. Mater. Trans. A, 2002, vol. 33A, pp. 2081-93) has been used to calculate the temperature and velocity fields associated with the thermally induced deformations and shrinkage driven melt flow, the solute conservation equation including both the liquid and a solid volume-averaged velocity is solved in the present study. In modeling examples, the macrosegregation formation caused by mechanically imposed as well as by thermally induced deformations has been calculated. The modeling results for an Al-4 wt pct Cu alloy indicate that even quite small volumetric strains (≈2 pct), which can be associated with thermally induced deformations, can lead to a macroscopic composition variation in the final casting comparable to that resulting from the solidification shrinkage induced melt flow. These results can be explained by the relatively large volumetric viscoplastic deformation in the coherent mush resulting from the applied constitutive model, as well as the relatively large difference in composition for the studied Al-Cu alloy in the solid and liquid phases at high solid fractions at which the deformation takes place.

Simultaneous determination of the quantity and isotopic signature of dissolved organic matter from soil water using high-performance liquid chromatography/isotope ratio mass spectrometry.

PubMed

Scheibe, Andrea; Krantz, Lars; Gleixner, Gerd

2012-01-30

We assessed the accuracy and utility of a modified high-performance liquid chromatography/isotope ratio mass spectrometry (HPLC/IRMS) system for measuring the amount and stable carbon isotope signature of dissolved organic matter (DOM) <1 µm. Using a range of standard compounds as well as soil solutions sampled in the field, we compared the results of the HPLC/IRMS analysis with those from other methods for determining carbon and (13)C content. The conversion efficiency of the in-line wet oxidation of the HPLC/IRMS averaged 99.3% for a range of standard compounds. The agreement between HPLC/IRMS and other methods in the amount and isotopic signature of both standard compounds and soil water samples was excellent. For DOM concentrations below 10 mg C L(-1) (250 ng C total) pre-concentration or large volume injections are recommended in order to prevent background interferences. We were able to detect large differences in the (13)C signatures of soil solution DOM sampled in 10 cm depth of plots with either C3 or C4 vegetation and in two different parent materials. These measurements also demonstrated changes in the (13)C signature that demonstrate rapid loss of plant-derived C with depth. Overall the modified HLPC/IRMS system has the advantages of rapid sample preparation, small required sample volume and high sample throughput, while showing comparable performance with other methods for measuring the amount and isotopic signature of DOM. Copyright © 2011 John Wiley & Sons, Ltd.

Heat capacity measurements of sub-nanoliter volumes of liquids using bimaterial microchannel cantilevers

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

Khan, M. F.; Miriyala, N.; Hassanpourfard, M.

Lab-on-a-Chip compatible techniques for thermal characterization of miniaturized volumes of liquid analytes are necessary in applications such as protein blotting, DNA melting, and drug development, where samples are either rare or volume-limited. We developed a closed-chamber calorimeter based on a bimaterial microchannel cantilever (BMC) for sub-nanoliter level thermal analysis. When the liquid-filled BMC is irradiated with infrared (IR) light at a specific wavelength, the IR absorption by the liquid analyte results in localized heat generation and the subsequent deflection of the BMC, due to a thermal expansion mismatch between the constituent materials. The time constant of the deflection, which ismore » dependent upon the heat capacity of the liquid analyte, can be directly measured by recording the time-dependent bending of the BMC. We have used the BMC to quantitatively measure the heat capacity of five volatile organic compounds. With a deflection noise level of ∼10 nm and a signal-to-noise ratio of 68:1, the BMC offers a sensitivity of 30.5 ms/(J g{sup −1 }K{sup −1}) and a resolution of 23 mJ/(g K) for ∼150 pl liquid for heat capacity measurements. This technique can be used for small-scale thermal characterization of different chemical and biological samples.« less

Simulation of elution profiles in liquid chromatography - II: Investigation of injection volume overload under gradient elution conditions applied to second dimension separations in two-dimensional liquid chromatography.

PubMed

Stoll, Dwight R; Sajulga, Ray W; Voigt, Bryan N; Larson, Eli J; Jeong, Lena N; Rutan, Sarah C

2017-11-10

An important research direction in the continued development of two-dimensional liquid chromatography (2D-LC) is to improve the detection sensitivity of the method. This is especially important in applications where injection of large volumes of effluent from the first dimension ( 1 D) column into the second dimension ( 2 D) column leads to severe 2 D peak broadening and peak shape distortion. For example, this is common when coupling two reversed-phase columns and the organic solvent content of the 1 D mobile phase overwhelms the 2 D column with each injection of 1 D effluent, leading to low resolution in the second dimension. In a previous study we validated a simulation approach based on the Craig distribution model and adapted from the work of Czok and Guiochon [1] that enabled accurate simulation of simple isocratic and gradient separations with very small injection volumes, and isocratic separations with mismatched injection and mobile phase solvents [2]. In the present study we have extended this simulation approach to simulate separations relevant to 2D-LC. Specifically, we have focused on simulating 2 D separations where gradient elution conditions are used, there is mismatch between the sample solvent and the starting point in the gradient elution program, injection volumes approach or even exceed the dead volume of the 2 D column, and the extent of sample loop filling is varied. To validate this simulation we have compared results from simulations and experiments for 101 different conditions, including variation in injection volume (0.4-80μL), loop filling level (25-100%), and degree of mismatch between sample organic solvent and the starting point in the gradient elution program (-20 to +20% ACN). We find that that the simulation is accurate enough (median errors in retention time and peak width of -1.0 and -4.9%, without corrections for extra-column dispersion) to be useful in guiding optimization of 2D-LC separations. However, this requires that real injection profiles obtained from 2D-LC interface valves are used to simulate the introduction of samples into the 2 D column. These profiles are highly asymmetric - simulation using simple rectangular pulses leads to peak widths that are far too narrow under many conditions. We believe the simulation approach developed here will be useful for addressing practical questions in the development of 2D-LC methods. Copyright © 2017 Elsevier B.V. All rights reserved.

Ultrasound-assisted ionic liquid dispersive liquid-liquid microextraction combined with graphite furnace atomic absorption spectrometric for selenium speciation in foods and beverages.

PubMed

Tuzen, Mustafa; Pekiner, Ozlem Zeynep

2015-12-01

A rapid and environmentally friendly ultrasound assisted ionic liquid dispersive liquid liquid microextraction (USA-IL-DLLME) was developed for the speciation of inorganic selenium in beverages and total selenium in food samples by using graphite furnace atomic absorption spectrometry. Some analytical parameters including pH, amount of complexing agent, extraction time, volume of ionic liquid, sample volume, etc. were optimized. Matrix effects were also investigated. Enhancement factor (EF) and limit of detection (LOD) for Se(IV) were found to be 150 and 12 ng L(-1), respectively. The relative standard deviation (RSD) was found 4.2%. The accuracy of the method was confirmed with analysis of LGC 6010 Hard drinking water and NIST SRM 1573a Tomato leaves standard reference materials. Optimized method was applied to ice tea, soda and mineral water for the speciation of Se(IV) and Se(VI) and some food samples including beer, cow's milk, red wine, mixed fruit juice, date, apple, orange, grapefruit, egg and honey for the determination of total selenium. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sol-gel polydimethylsiloxane/poly(vinylalcohol)-coated stir bar sorptive extraction of organophosphorus pesticides in honey and their determination by large volume injection GC.

PubMed

Yu, Chunhe; Hu, Bin

2009-01-01

A PDMS/poly(vinylalcohol) (PDMS/PVA) film prepared through a sol-gel process was coated on stir bars for sorptive extraction, followed by liquid desorption and large volume injection-GC-flame photometric detector (LVI-GC-FPD) for the determination of five organophosphorus pesticides (OPPs) (phorate, fenitrothion, malathion, parathion, and quinalphos) in honey. The preparation reproducibility of PDMS/PVA-coated stir bar ranged from 4.3 to 13.4% (n = 4) in one batch, and from 6.0 to 12.6% (n = 4) in batch to batch. And one prepared stir bar can be used for more than 50 times without apparent coating loss. The significant parameters affecting stir bar sorptive extraction (SBSE) were investigated and optimized. The LODs for five OPPs ranged from 0.013 (parathion) to 0.081 microg/L (phorate) with the RSDs ranging from 5.3 to 14.2% (c = 1 microg/L, n = 6). The proposed method was successfully applied to the analysis of five OPPs in honey.

Numerical investigation of performance of vane-type propellant management device by VOF methods

NASA Astrophysics Data System (ADS)

Liu, J. T.; Zhou, C.; Wu, Y. L.; Zhuang, B. T.; Li, Y.

2015-01-01

The orbital propellant management performance of the vane-type tank is so important for the propellant system and it determines the lifetime of the satellite. The propellant in the tank can be extruded by helium gas. To study the two phase distribution in the vane-type surface tension tank and the capability of the vane-type propellant management device (PMD), a large volume vane-type surface tension tank is analysed using 3-D unsteady numerical simulations. VOF methods are used to analyse the location of the interface of the two phase. Performances of the propellant acquisition vanes and propellant refillable reservoir in the tank are investigated. The flow conductivity of the propellant acquisition vanes and the liquid storage capacity of propellant refillable reservoir can be affected by the value of the gravity and the volume of the propellant in the tank. To avoid the large resistance causing by surface tension in an outflow of a small hole, the design of the vanes in a propellant refillable reservoir should have suitable space.

Trickle-bed root culture bioreactor design and scale-up: growth, fluid-dynamics, and oxygen mass transfer.

PubMed

Ramakrishnan, Divakar; Curtis, Wayne R

2004-10-20

Trickle-bed root culture reactors are shown to achieve tissue concentrations as high as 36 g DW/L (752 g FW/L) at a scale of 14 L. Root growth rate in a 1.6-L reactor configuration with improved operational conditions is shown to be indistinguishable from the laboratory-scale benchmark, the shaker flask (mu=0.33 day(-1)). These results demonstrate that trickle-bed reactor systems can sustain tissue concentrations, growth rates and volumetric biomass productivities substantially higher than other reported bioreactor configurations. Mass transfer and fluid dynamics are characterized in trickle-bed root reactors to identify appropriate operating conditions and scale-up criteria. Root tissue respiration goes through a minimum with increasing liquid flow, which is qualitatively consistent with traditional trickle-bed performance. However, liquid hold-up is much higher than traditional trickle-beds and alternative correlations based on liquid hold-up per unit tissue mass are required to account for large changes in biomass volume fraction. Bioreactor characterization is sufficient to carry out preliminary design calculations that indicate scale-up feasibility to at least 10,000 liters.

A proposed method to minimize waste from institutional radiation safety surveillance programs through the application of expected value statistics.

PubMed

Emery, R J

1997-03-01

Institutional radiation safety programs routinely use wipe test sampling and liquid scintillation counting analysis to indicate the presence of removable radioactive contamination. Significant volumes of liquid waste can be generated by such surveillance activities, and the subsequent disposal of these materials can sometimes be difficult and costly. In settings where large numbers of negative results are regularly obtained, the limited grouping of samples for analysis based on expected value statistical techniques is possible. To demonstrate the plausibility of the approach, single wipe samples exposed to varying amounts of contamination were analyzed concurrently with nine non-contaminated samples. Although the sample grouping inevitably leads to increased quenching with liquid scintillation counting systems, the effect did not impact the ability to detect removable contamination in amounts well below recommended action levels. Opportunities to further improve this cost effective semi-quantitative screening procedure are described, including improvements in sample collection procedures, enhancing sample-counting media contact through mixing and extending elution periods, increasing sample counting times, and adjusting institutional action levels.

Synthesis and Compatibility of Ionic Liquid Containing Rod-Coil Polyimide Gel Electrolytes with Lithium Metal Electrodes

NASA Technical Reports Server (NTRS)

Tigelaar, Dean M.; Palker, Allyson E.; Meador, Mary Ann B.; Bennett, William R.

2008-01-01

A highly cross-linked polyimide-polyethylene oxide copolymer has been synthesized that is capable of holding large volumes of liquid component, simultaneously maintaining good dimensional stability. An amine end capped oligomer was made that was imidized in solution, followed by reaction with a triisocyanate in the presence of desired additives at ambient temperature. Polymer films are able to hold over 4 times their weight in room temperature ionic liquid RTIL or carbonate solvent. Electrolytes were studied that contained varying amounts of RTIL, lithium trifluoromethanesulfonimide LiTFSi, and alumina nanoparticles. Electrochemical stability of these electrolytes with lithium metal electrodes was studied by galvanic cycling and impedance spectroscopy. Improved cycling stability and decreased interfacial resistance were observed when increasing amounts of RTIL and LiTFSi were added. The addition of small amounts of alumina further decreased interfacial resistance by nearly an order of magnitude. During the course of the study, cycling stability increased from less than 3 to greater than 1000 h at 60 C and 0.25 mA/cm2 current density.

An Ultra-Sensitive Method for the Analysis of Perfluorinated ...

EPA Pesticide Factsheets

In epidemiological research, it has become increasingly important to assess subjects' exposure to different classes of chemicals in multiple environmental media. It is a common practice to aliquot limited volumes of samples into smaller quantities for specific trace level chemical analysis. A novel method was developed for the determination of 14 perfluorinated alkyl acids (PFAAs) in small volumes (10 mL) of drinking water using off-line solid phase extraction (SPE) pre-treatment followed by on-line pre-concentration on WAX column before analysis on column-switching high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). In general, large volumes (100 - 1000 mL) have been used for the analysis of PFAAs in drinking water. The current method requires approximately 10 mL of drinking water concentrated by using an SPE cartridge and eluted with methanol. A large volume injection of the extract was introduced on to a column-switching HPLC-MS/MS using a mix-mode SPE column for the trace level analysis of PFAAs in water. The recoveries for most of the analytes in the fortified laboratory blanks ranged from 73±14% to 128±5%. The lowest concentration minimum reporting levels (LCMRL) for the 14 PFAAs ranged from 0.59 to 3.4 ng/L. The optimized method was applied to a pilot-scale analysis of a subset of drinking water samples from an epidemiological study. These samples were collected directly from the taps in the households of Ohio and Nor

Automated dynamic hollow fiber liquid-liquid-liquid microextraction combined with capillary electrophoresis for speciation of mercury in biological and environmental samples.

PubMed

Li, Pingjing; He, Man; Chen, Beibei; Hu, Bin

2015-10-09

A simple home-made automatic dynamic hollow fiber based liquid-liquid-liquid microextraction (AD-HF-LLLME) device was designed and constructed for the simultaneous extraction of organomercury and inorganic mercury species with the assistant of a programmable flow injection analyzer. With 18-crown-6 as the complexing reagent, mercury species including methyl-, ethyl-, phenyl- and inorganic mercury were extracted into the organic phase (chlorobenzene), and then back-extracted into the acceptor phase of 0.1% (m/v) 3-mercapto-1-propanesulfonic acid (MPS) aqueous solution. Compared with automatic static (AS)-HF-LLLME system, the extraction equilibrium of target mercury species was obtained in shorter time with higher extraction efficiency in AD-HF-LLLME system. Based on it, a new method of AD-HF-LLLME coupled with large volume sample stacking (LVSS)-capillary electrophoresis (CE)/UV detection was developed for the simultaneous analysis of methyl-, phenyl- and inorganic mercury species in biological samples and environmental water. Under the optimized conditions, AD-HF-LLLME provided high enrichment factors (EFs) of 149-253-fold within relatively short extraction equilibrium time (25min) and good precision with RSD between 3.8 and 8.1%. By combining AD-HF-LLLME with LVSS-CE/UV, EFs were magnified up to 2195-fold and the limits of detection (at S/N=3) for target mercury species were improved to be sub ppb level. Copyright © 2015 Elsevier B.V. All rights reserved.

Determination of the thermal stability of fluids by tensimetry - Instrumentation and procedure

NASA Technical Reports Server (NTRS)

Helmick, Larry S.; Jones, William R., Jr.

1990-01-01

A computerized tensimeter and experimental procedure for determination of the thermal decomposition temperature (T sub d) of perfluoro alkylethers were developed and tested. Both the apparatus and the procedure are described in detail. Results of testing with bis(2-ethylhexyl) phthalate and trimethylolpropane triheptanoate demonstrate that the reciprocal of the decomposition temperature is a linear function of the logarithm of the gas volume/heated liquid volume ratio. The T sub d obtained for each compound at a gas volume/heated liquid volume ration of one was similar to the value previously reported using an isoteniscope technique. Results of testing with a polymer of hexafluoropropylene oxide demonstrate that this instrument and procedure can be used to determine the T sub d of perfluoro alkylethers.

Determination of the thermal stability of perfluoroalkylethers by tensimetry: Instrumentation and Procedure

NASA Technical Reports Server (NTRS)

Helmick, Larry S.; Jones, William R., Jr.

1989-01-01

A computerized tensimeter and experimental procedure for determination of the thermal decomposition temperature (T sub d) of perfluoro alkylethers were developed and tested. Both the apparatus and the procedure are described in detail. Results of testing with bis(2-ethylhexyl) phthalate and trimethylolpropane triheptanoate demonstrate that the reciprocal of the decomposition temperature is a linear function of the logarithm of the gas volume/heated liquid volume ratio. The T sub d obtained for each compound at a gas volume/heated liquid volume ration of one was similar to the value previously reported using an isoteniscope technique. Results of testing with a polymer of hexafluoropropylene oxide demonstrate that this instrument and procedure can be used to determine the T sub d of perfluoroalkylethers.

Comparing volume of fluid and level set methods for evaporating liquid-gas flows

NASA Astrophysics Data System (ADS)

Palmore, John; Desjardins, Olivier

2016-11-01

This presentation demonstrates three numerical strategies for simulating liquid-gas flows undergoing evaporation. The practical aim of this work is to choose a framework capable of simulating the combustion of liquid fuels in an internal combustion engine. Each framework is analyzed with respect to its accuracy and computational cost. All simulations are performed using a conservative, finite volume code for simulating reacting, multiphase flows under the low-Mach assumption. The strategies used in this study correspond to different methods for tracking the liquid-gas interface and handling the transport of the discontinuous momentum and vapor mass fractions fields. The first two strategies are based on conservative, geometric volume of fluid schemes using directionally split and un-split advection, respectively. The third strategy is the accurate conservative level set method. For all strategies, special attention is given to ensuring the consistency between the fluxes of mass, momentum, and vapor fractions. The study performs three-dimensional simulations of an isolated droplet of a single component fuel evaporating into air. Evaporation rates and vapor mass fractions are compared to analytical results.

Uncertainty contribution on the density of liquids due to unknown sinker temperature in hydrostatic weighing apparatus

NASA Astrophysics Data System (ADS)

Schiebl, M.; Zelenka, Z.; Buchner, C.; Pohl, R.; Steindl, D.

2018-02-01

In this study, the influence of the unknown sinker temperature on the measured density of liquids is evaluated. Generally, due to the intrinsic temperature instability of the heat bath temperature controller, the system will never reach thermal equilibrium but instead will oscillate around a mean temperature. The sinker temperature follows this temperature oscillation with a certain time lag. Since the sinker temperature is not measured directly in a hydrostatic weighing apparatus, the temperature of the sinker, and thus in turn the volume of the sinker, is not known exactly. As a consequence, this leads to uncertainty in the value of the density of the liquid. From an analysis of the volume relaxation of the sinker immersed into a heat bath with time-dependent temperature characteristics, the heat transfer coefficient can be estimated, and thus a characteristic time constant for achieving quasi thermal equilibrium for a hydrostatic weighing apparatus is proposed. Additionally, from a theoretical analysis of the transient behavior of the sinker volume, the systematic deviation of the theoretical to the actual measured liquid density is calculated.

Integrated acoustic phase separator and multiphase fluid composition monitoring apparatus and method

DOEpatents

Sinha, Dipen N.

2016-01-12

An apparatus and method for down hole gas separation from the multiphase fluid flowing in a wellbore or a pipe, for determining the quantities of the individual components of the liquid and the flow rate of the liquid, and for remixing the component parts of the fluid after which the gas volume may be measured, without affecting the flow stream, are described. Acoustic radiation force is employed to separate gas from the liquid, thereby permitting measurements to be separately made for these two components; the liquid (oil/water) composition is determined from ultrasonic resonances; and the gas volume is determined from capacitance measurements. Since the fluid flows around and through the component parts of the apparatus, there is little pressure difference, and no protection is required from high pressure differentials.

Integrated acoustic phase separator and multiphase fluid composition monitoring apparatus and method

DOEpatents

Sinha, Dipen N

2014-02-04

An apparatus and method for down hole gas separation from the multiphase fluid flowing in a wellbore or a pipe, for determining the quantities of the individual components of the liquid and the flow rate of the liquid, and for remixing the component parts of the fluid after which the gas volume may be measured, without affecting the flow stream, are described. Acoustic radiation force is employed to separate gas from the liquid, thereby permitting measurements to be separately made for these two components; the liquid (oil/water) composition is determined from ultrasonic resonances; and the gas volume is determined from capacitance measurements. Since the fluid flows around and through the component parts of the apparatus, there is little pressure difference, and no protection is required from high pressure differentials.

Volcanic Perspective on Plutonism based on Patterns in Evolution in Long-Lived Continental Volcanic Systems

NASA Astrophysics Data System (ADS)

Grunder, A. L.; Harris, R. N.; Walker, B. A.; Giles, D.; Klemetti, E. W.

2008-12-01

Volcanic rocks represent a biased view of magmatism, but provide critical quenched samples and temporal constraints of magmatic evolution obscured in the plutonic record. We here draw on the records from the Aucanquilcha Volcanic Cluster (AVC; 10 to 0 Ma) in northern Chile and from the mid-Tertiary volcanic field in east-central Nevada (ECNVF; ~40-32 Ma) to consider how evolutionary patterns of intermediate composition volcanic systems bear on the magmatic reworking of the continental crust by plutons and batholiths. Despite disparate tectonic setting (subduction vs extension) and volumes (70 km crust for the ~300 km 3 AVC versus and ~40 km crust for the ~3000 km 3 ECNVF) both volcanic systems share a history of early compositionally diverse volcanism, followed by a stage of more centralized and voluminous dacitic volcanism, which in turn is followed by waning of volcanism. The compositional change and the rapid increase in magma output rate after about half the lifetime of the system is a characteristic pattern of long- lived continental volcanic systems based on a compilation of volume-composition data. The middle, voluminous stage corresponds to the hottest upper crustal conditions, deduced from Al-in-amphibole geothermobarometry and Ti-in-zircon thermometry of the AVC. The middle stage rocks also have textures indicating hybridization of mixed magmas. Simple thermal models of heat input via intraplating readily allow for generation of partially molten crust above the sill, but they do not emulate the rapid increase of magma after some incubation time. We propose that there is a feedback in which a critical thickness of partially molten crust, consisting in part of magmatic precursors, can be readily convectively stirred and mixed with magma of the underplating sill, rapidly creating a large, hybrid and relatively hot body of magma. Stirring facilitates separation of a liquid-enriched extract. The volume of liquid extracted may be small relative to residual crystal-liquid mush, so that compositional differences between plutons and eruptives are cryptic.

Predictive thermodynamics for ionic solids and liquids.

PubMed

Glasser, Leslie; Jenkins, H Donald Brooke

2016-08-21

The application of thermodynamics is simple, even if the theory may appear intimidating. We describe tools, developed over recent years, which make it easy to estimate often elusive thermodynamic parameter values, generally (but not exclusively) for ionic materials, both solid and liquid, as well as for their solid hydrates and solvates. The tools are termed volume-based thermodynamics (VBT) and thermodynamic difference rules (TDR), supplemented by the simple salt approximation (SSA) and single-ion values for volume, Vm, heat capacity, , entropy, , formation enthalpy, ΔfH°, and Gibbs formation energy, ΔfG°. These tools can be applied to provide values of thermodynamic and thermomechanical properties such as standard enthalpy of formation, ΔfH°, standard entropy, , heat capacity, Cp, Gibbs function of formation, ΔfG°, lattice potential energy, UPOT, isothermal expansion coefficient, α, and isothermal compressibility, β, and used to suggest the thermodynamic feasibility of reactions among condensed ionic phases. Because many of these methods yield results largely independent of crystal structure, they have been successfully extended to the important and developing class of ionic liquids as well as to new and hypothesised materials. Finally, these predictive methods are illustrated by application to K2SnCl6, for which known experimental results are available for comparison. A selection of applications of VBT and TDR is presented which have enabled input, usually in the form of thermodynamics, to be brought to bear on a range of topical problems. Perhaps the most significant advantage of VBT and TDR methods is their inherent simplicity in that they do not require a high level of computational expertise nor expensive high-performance computation tools - a spreadsheet will usually suffice - yet the techniques are extremely powerful and accessible to non-experts. The connection between formula unit volume, Vm, and standard thermodynamic parameters represents a major advance exploited by these techniques.

The Density and Compressibility of BaCO3-SrCO3-CaCO3-K2CO3-Na2CO3-Li2CO3 Liquids: New Measurements and a Systematic Trend with Cation Field Strength

NASA Astrophysics Data System (ADS)

Hurt, S. M.; Lange, R. A.; Ai, Y.

2015-12-01

The volumetric properties of multi-component carbonate liquids are required to extend thermodynamic models that describe partial melting of the deep mantle (e.g. pMELTS; Ghiorso et al., 2003) to carbonate-bearing lithologies. Carbonate in the mantle is an important reservoir of carbon, which is released to the atmosphere as CO2 through volcanism, and thus contributes to the carbon cycle. Although MgCO3 is the most important carbonate component in the mantle, it is not possible to directly measure the 1-bar density and compressibility of MgCO3 liquid because, like other alkaline-earth carbonates, it decomposes at a temperature lower than its melting temperature. Despite this challenge, Liu and Lange (2003) and O'Leary et al. (2015) showed that the one bar molar volume, thermal expansion and compressibility of the CaCO3 liquid component could be obtained by measuring the density and sound speeds of stable liquids in the CaCO3-Li2CO3-Na2CO3-K2CO3 quaternary system at one bar. In this study, this same strategy is employed on SrCO3- and BaCO3-bearing alkali carbonate liquids. The density and sound speed of seven liquids in the SrCO3-Li2CO3-Na2CO3-K2CO3 quaternary and three liquids in the BaCO3-Li2CO3-Na2CO3-K2CO3 quaternary were measured from 739-1367K, with SrCO3 and BaCO3 concentrations ranging from 10-50 mol%. The density measurements were made using the double-bob Archimedean method and sound speeds were obtained with a frequency-sweep acoustic interferometer. The molar volume and sound speed measurements were used to calculate the isothermal compressibility of each liquid, and the results show the volumetric properties mix ideally with composition. The partial molar volume and compressibility of the SrCO3 and BaCO3 components are compared to those obtained for the CaCO3 component as a function of cation field strength. The results reveal a systematic trend that allows the partial molar volume and compressibility of the MgCO3 liquid component to be estimated.

Preconcentration and determination of ceftazidime in real samples using dispersive liquid-liquid microextraction and high-performance liquid chromatography with the aid of experimental design.

PubMed

Razmi, Rasoul; Shahpari, Behrouz; Pourbasheer, Eslam; Boustanifar, Mohammad Hasan; Azari, Zhila; Ebadi, Amin

2016-11-01

A rapid and simple method for the extraction and preconcentration of ceftazidime in aqueous samples has been developed using dispersive liquid-liquid microextraction followed by high-performance liquid chromatography analysis. The extraction parameters, such as the volume of extraction solvent and disperser solvent, salt effect, sample volume, centrifuge rate, centrifuge time, extraction time, and temperature in the dispersive liquid-liquid microextraction process, were studied and optimized with the experimental design methods. Firstly, for the preliminary screening of the parameters the taguchi design was used and then, the fractional factorial design was used for significant factors optimization. At the optimum conditions, the calibration curves for ceftazidime indicated good linearity over the range of 0.001-10 μg/mL with correlation coefficients higher than the 0.98, and the limits of detection were 0.13 and 0.17 ng/mL, for water and urine samples, respectively. The proposed method successfully employed to determine ceftazidime in water and urine samples and good agreement between the experimental data and predictive values has been achieved. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Chen, Dafen; Jiang, Jiuchun; Kim, Gi-Heon

Choosing a proper cooling method for a lithium-ion (Li-ion) battery pack for electric drive vehicles (EDVs) and making an optimal cooling control strategy to keep the temperature at a optimal range of 15 degrees C to 35 degrees C is essential to increasing safety, extending the pack service life, and reducing costs. When choosing a cooling method and developing strategies, trade-offs need to be made among many facets such as costs, complexity, weight, cooling effects, temperature uniformity, and parasitic power. This paper considers four cell-cooling methods: air cooling, direct liquid cooling, indirect liquid cooling, and fin cooling. To evaluate theirmore » effectiveness, these methods are assessed using a typical large capacity Li-ion pouch cell designed for EDVs from the perspective of coolant parasitic power consumption, maximum temperature rise, temperature difference in a cell, and additional weight used for the cooling system. We use a state-of-the-art Li-ion battery electro-chemical thermal model. The results show that under our assumption an air-cooling system needs 2 to 3 more energy than other methods to keep the same average temperature; an indirect liquid cooling system has the lowest maximum temperature rise; and a fin cooling system adds about 40% extra weight of cell, which weighs most, when the four kinds cooling methods have the same volume. Indirect liquid cooling is a more practical form than direct liquid cooling though it has slightly lower cooling performance.« less

Gas-Liquid Supersonic Cleaning and Cleaning Verification Spray System

NASA Technical Reports Server (NTRS)

Parrish, Lewis M.

2009-01-01

NASA Kennedy Space Center (KSC) recently entered into a nonexclusive license agreement with Applied Cryogenic Solutions (ACS), Inc. (Galveston, TX) to commercialize its Gas-Liquid Supersonic Cleaning and Cleaning Verification Spray System technology. This technology, developed by KSC, is a critical component of processes being developed and commercialized by ACS to replace current mechanical and chemical cleaning and descaling methods used by numerous industries. Pilot trials on heat exchanger tubing components have shown that the ACS technology provides for: Superior cleaning in a much shorter period of time. Lower energy and labor requirements for cleaning and de-scaling uper.ninih. Significant reductions in waste volumes by not using water, acidic or basic solutions, organic solvents, or nonvolatile solid abrasives as components in the cleaning process. Improved energy efficiency in post-cleaning heat exchanger operations. The ACS process consists of a spray head containing supersonic converging/diverging nozzles, a source of liquid gas; a novel, proprietary pumping system that permits pumping liquid nitrogen, liquid air, or supercritical carbon dioxide to pressures in the range of 20,000 to 60,000 psi; and various hoses, fittings, valves, and gauges. The size and number of nozzles can be varied so the system can be built in configurations ranging from small hand-held spray heads to large multinozzle cleaners. The system also can be used to verify if a part has been adequately cleaned.

Scalable Synthesis of Cholesteric Glassy Liquid Crystals

DOE PAGES

Wallace, Jason U.; Shestopalov, Alexander; Kosc, Tanya; ...

2018-03-15

Capable of non-absorbing circular polarization of unpolarized incident light, cholesteric glassy liquid crystals consisting of hybrid chiral-nematic pendants to volume-excluding cores are potentially useful for the fabrication of various robust optical devices. As illustrated in this study, the well-oriented glassy film of enantiomeric Bz3ChN, with a glass transition at 73 °C and a cholesteric-to-isotropic transition at 295 °C, exhibits a selective reflection band centered at approximately 410 nm, an exceptional set of properties well suited for optical device exploration. To enable sustainable, large-scale synthesis of this material class for widespread applications, a productive strategy has been established, requiring a meremore » three-step scheme with an overall yield, atom economy, and reaction mass efficiency at 34%, 33% and 12%, respectively. Lastly, while amenable to improvements, the resultant green chemistry metrics are encouraging as the first attempt.« less

Ocean thermal plant

NASA Technical Reports Server (NTRS)

Owens, L. J. (Inventor)

1978-01-01

A floating energy converter is described which uses large volumes of sea water to produce electrical power. In this plant, a fluid working medium is pumped to an evaporator where is is heated by a flow of warm surface sea water. The fluid in liquid form boils to a pressurized gas vapor which is routed to drive a turbine that, in turn, drives a generator for producing electricity. The gas vapor then enters a condenser immersed in cold sea water pumped from lower depths, condenses to its original liquid form, and then pumped to the evaporator to repeat the cycle. Modular components can be readily interchanged on the ocean thermal unit and inlet pipes for the sea water are provided with means for maintaining the pipes in alignment with the oncoming current. The modular construction allows for the testing of various components to provide a more rapid optimization of a standardized plant.

The onset of electrospray: the universal scaling laws of the first ejection

PubMed Central

Gañán-Calvo, A. M.; López-Herrera, J. M.; Rebollo-Muñoz, N.; Montanero, J. M.

2016-01-01

The disintegration of liquid drops with low electrical conductivity and subject to an electric field is investigated both theoretically and experimentally. This disintegration takes place through the development of a conical cusp that eventually ejects an ultrathin liquid ligament. A first tiny drop is emitted from the end of this ligament. Due to its exceptionally small size and large electric charge per unit volume, that drop has been the object of relevant recent studies. In this paper, universal scaling laws for the diameter and electric charge of the first issued droplet are proposed and validated both numerically and experimentally. Our analysis shows how charge relaxation is the mechanism that differentiates the onset of electrospray, including the first droplet ejection, from the classical steady cone-jet mode. In this way, our study identifies when and where charge relaxation and electrokinetic phenomena come into play in electrospray, a subject of live controversy in the field. PMID:27581554

Scalable Synthesis of Cholesteric Glassy Liquid Crystals

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

Wallace, Jason U.; Shestopalov, Alexander; Kosc, Tanya

2018-03-08

Capable of non-absorbing circular polarization of unpolarized incident light, cholesteric glassy liquid crystals consisting of hybrid chiral-nematic pendants to volume-excluding cores are potentially useful for the fabrication of various robust optical devices. As illustrated in this study, the well-oriented glassy film of enantiomeric Bz3ChN, with a glass transition at 73 oC and a cholesteric-to-isotropic transition at 295 oC, exhibits a selective reflection band centered at approximately 410 nm, an exceptional set of properties well suited for optical device exploration. To enable sustainable, large-scale synthesis of this material class for widespread applications, a productive strategy has been established, requiring a meremore » three-step scheme with an overall yield, atom economy, and reaction mass efficiency at 34, 33 and 12 %, respectively. While amenable to improvements, the resultant green chemistry metrics are encouraging as the first attempt.« less

Oral Cooling and Carbonation Increase the Perception of Drinking and Thirst Quenching in Thirsty Adults

PubMed Central

Peyrot des Gachons, Catherine; Avrillier, Julie; Gleason, Michael; Algarra, Laure; Zhang, Siyu; Mura, Emi; Nagai, Hajime

2016-01-01

Fluid ingestion is necessary for life, and thirst sensations are a prime motivator to drink. There is evidence of the influence of oropharyngeal stimulation on thirst and water intake in both animals and humans, but how those oral sensory cues impact thirst and ultimately the amount of liquid ingested is not well understood. We investigated which sensory trait(s) of a beverage influence the thirst quenching efficacy of ingested liquids and the perceived amount ingested. We deprived healthy individuals of liquid and food overnight (> 12 hours) to make them thirsty. After asking them to drink a fixed volume (400 mL) of an experimental beverage presenting one or two specific sensory traits, we determined the volume ingested of additional plain, ‘still’, room temperature water to assess their residual thirst and, by extension, the thirst-quenching properties of the experimental beverage. In a second study, participants were asked to drink the experimental beverages from an opaque container through a straw and estimate the volume ingested. We found that among several oro-sensory traits, the perceptions of coldness, induced either by cold water (thermally) or by l-menthol (chemically), and the feeling of oral carbonation, strongly enhance the thirst quenching properties of a beverage in water-deprived humans (additional water intake after the 400 ml experimental beverage was reduced by up to 50%). When blinded to the volume of liquid consumed, individual’s estimation of ingested volume is increased (~22%) by perceived oral cold and carbonation, raising the idea that cold and perhaps CO2 induced-irritation sensations are included in how we normally encode water in the mouth and how we estimate the quantity of volume swallowed. These findings have implications for addressing inadequate hydration state in populations such as the elderly. PMID:27685093

Liquid air cycle engines

NASA Technical Reports Server (NTRS)

Rosevear, Jerry

1992-01-01

Given here is a definition of Liquid Air Cycle Engines (LACE) and existing relevant technologies. Heat exchanger design and fabrication techniques, the handling of liquid hydrogen to achieve the greatest heat sink capabilities, and air decontamination to prevent heat exchanger fouling are discussed. It was concluded that technology needs to be extended in the areas of design and fabrication of heat exchangers to improve reliability along with weight and volume reductions. Catalysts need to be improved so that conversion can be achieved with lower quantities and lower volumes. Packaging studies need to be investigated both analytically and experimentally. Recycling with slush hydrogen needs further evaluation with experimental testing.

Shock absorber servicing tool

NASA Technical Reports Server (NTRS)

Koepler, Jack L. (Inventor); Hill, Robert L. (Inventor)

1981-01-01

A tool to assist in the servicing of a shock absorber wherein the shock absorber is constructed of a pair of aligned gas and liquid filled chambers. Each of the chambers is separated by a movable separator member. Maximum efficiency of the shock absorber is achieved in the locating of a precise volume of gas within the gas chamber and a precise volume of liquid within the liquid chamber. The servicing tool of this invention employs a rod which is to connect with the separator and by observation of the position of the rod with respect to the gauge body, the location of the separator is ascertained even though it is not directly observable.

Simplification and validation of a large volume polyurethane foam sampler for the analysis of persistent hydrophobic compounds in drinking water.

PubMed

Choi, J W; Lee, J H; Moon, B S; Kannan, K

2008-08-01

The use of a large volume polyurethane foam (PUF) sampler was validated for rapid extraction of persistent organic pollutants (POPs), such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), in raw water and treated water from drinking water plants. To validate the recovery of target compounds in the sampling process, a (37)Cl-labeled standard was spiked into the 1st PUF plug prior to filtration. An accelerated solvent extraction method, as a pressurized liquid extractor (PLE), was optimized to extract the PUF plug. For sample preparation, tandem column chromatography (TCC) clean-up was used for rapid analysis. The recoveries of labeled compounds in the analytical method were 80-110% (n = 9). The optimized PUF-PLE-TCC method was applied in the analysis of raw water and treated potable water from seven drinking water plants in South Korea. The sample volume used was between 18 and 102 L for raw water at a flow rate of 0.4-2 L min(-1), 95 and 107 L for treated water at a flow rate of 1.5-2.2 L min(-1). Limit of quantitation (LOQ) was a function of sample volume and it decreased with increasing sample volume. The LOQ of PCDD/Fs in raw waters analyzed by this method was 3-11 times lower than that described using large-size disk-type solid phase extraction (SPE) method. The LOQ of PCDD/F congeners in raw water and treated water were 0.022-3.9 ng L(-1) and 0.018-0.74 ng L(-1), respectively. Octachlorinated dibenzo-p-dioxin (OCDD) was found in some raw water samples, while their concentrations were well below the tentative criterion set by the Japanese Environmental Ministry for drinking water. OCDD was below the LOQ in the treated drinking water.

Liquid rocket booster integration study. Volume 4: Reviews and presentation material

NASA Technical Reports Server (NTRS)

1988-01-01

Liquid rocket booster integration study is presented. Volume 4 contains materials presented at the MSFC/JSC/KSC Integrated Reviews and Working Group Sessions, and the Progress Reviews presented to the KSC Study Manager. The following subject areas are covered: initial impact assessment; conflicts with the on-going STS mission; access to the LRB at the PAD; the activation schedule; transition requirements; cost methodology; cost modelling approach; and initial life cycle cost.

Expanding the calculation of activation volumes: Self-diffusion in liquid water

NASA Astrophysics Data System (ADS)

Piskulich, Zeke A.; Mesele, Oluwaseun O.; Thompson, Ward H.

2018-04-01

A general method for calculating the dependence of dynamical time scales on macroscopic thermodynamic variables from a single set of simulations is presented. The approach is applied to the pressure dependence of the self-diffusion coefficient of liquid water as a particularly useful illustration. It is shown how the activation volume associated with diffusion can be obtained directly from simulations at a single pressure, avoiding approximations that are typically invoked.

Melting properties of Pt and its transport coefficients in liquid states under high pressures

NASA Astrophysics Data System (ADS)

Wang, Pan-Pan; Shao, Ju-Xiang; Cao, Qi-Long

2016-11-01

Molecular dynamics (MD) simulations of the melting and transport properties in liquid states of platinum for the pressure range (50-200 GPa) are reported. The melting curve of platinum is consistent with previous ab initio MD simulation results and the first-principles melting curve. Calculated results for the pressure dependence of fusion entropy and fusion volume show that the fusion entropy and the fusion volume decrease with increasing pressure, and the ratio of the fusion volume to fusion entropy roughly reproduces the melting slope, which has a moderate decrease along the melting line. The Arrhenius law well describes the temperature dependence of self-diffusion coefficients and viscosity under high pressure, and the diffusion activation energy decreases with increasing pressure, while the viscosity activation energy increases with increasing pressure. In addition, the entropy-scaling law, proposed by Rosenfeld under ambient pressure, still holds well for liquid Pt under high pressure conditions.

Relation between heat of vaporization, ion transport, molar volume, and cation-anion binding energy for ionic liquids.

PubMed

Borodin, Oleg

2009-09-10

A number of correlations between heat of vaporization (H(vap)), cation-anion binding energy (E(+/-)), molar volume (V(m)), self-diffusion coefficient (D), and ionic conductivity for 29 ionic liquids have been investigated using molecular dynamics (MD) simulations that employed accurate and validated many-body polarizable force fields. A significant correlation between D and H(vap) has been found, while the best correlation was found for -log(DV(m)) vs H(vap) + 0.28E(+/-). A combination of enthalpy of vaporization and a fraction of the cation-anion binding energy was suggested as a measure of the effective cohesive energy for ionic liquids. A deviation of some ILs from the reported master curve is explained based upon ion packing and proposed diffusion pathways. No general correlations were found between the ion diffusion coefficient and molecular volume or the diffusion coefficient and cation/anion binding energy.

Catalytic two-stage coal liquefaction process having improved nitrogen removal

DOEpatents

Comolli, Alfred G.

1991-01-01

A process for catalytic multi-stage hydrogenation and liquefaction of coal to produce high yields of low-boiling hydrocarbon liquids containing low concentrations of nitogen compounds. First stage catalytic reaction conditions are 700.degree.-800.degree. F. temperature, 1500-3500 psig hydrogen partial pressure, with the space velocity maintained in a critical range of 10-40 lb coal/hr ft.sup.3 catalyst settled volume. The first stage catalyst has 0.3-1.2 cc/gm total pore volume with at least 25% of the pore volume in pores having diameters of 200-2000 Angstroms. Second stage reaction conditions are 760.degree.-870.degree. F. temperature with space velocity exceeding that in the first stage reactor, so as to achieve increased hydrogenation yield of low-boiling hydrocarbon liquid products having at least 75% removal of nitrogen compounds from the coal-derived liquid products.

[Optimization of Polysaccharide Extraction from Spirodela polyrrhiza by Plackett-Burman Design Combined with Box-Behnken Response Surface Methodology].

PubMed

Jiang, Zheng; Wang, Hong; Wu, Qi-nan

2015-06-01

To optimize the processing of polysaccharide extraction from Spirodela polyrrhiza. Five factors related to extraction rate of polysaccharide were optimized by the Plackett-Burman design. Based on this study, three factors, including alcohol volume fraction, extraction temperature and ratio of material to liquid, were regarded as investigation factors by Box-Behnken response surface methodology. The effect order of three factors on the extraction rate of polysaccharide from Spirodela polyrrhiza were as follows: extraction temperature, alcohol volume fraction,ratio of material to liquid. According to Box-Behnken response, the best extraction conditions were: alcohol volume fraction of 81%, ratio of material to liquid of 1:42, extraction temperature of 100 degrees C, extraction time of 60 min for four times. Plackett-Burman design and Box-Behnken response surface methodology used to optimize the extraction process for the polysaccharide in this study is effective and stable.

Axial jet mixing of ethanol in cylindrical containers during weightlessness

NASA Technical Reports Server (NTRS)

Aydelott, J. C.

1979-01-01

An experimental program was conducted to examine the liquid flow patterns that result from the axial jet mixing of ethanol in 10-centimeter-diameter cylindrical tanks in weightlessness. A convex hemispherically ended tank and two Centaur liquid-hydrogen-tank models were used for the study. Four distinct liquid flow patterns were observed to be a function of the tank geometry, the liquid-jet velocity, the volume of liquid in the tank, and the location of the tube from which the liquid jet exited.

40 CFR 60.111a - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Storage Vessels for Petroleum Liquids for..., reservoir, or container used for the storage of petroleum liquids, but does not include: (1) Pressure... tanks if the total volume of petroleum liquids added to and taken from a tank annually does not exceed...

40 CFR 63.1061 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... shall have the meaning given them in the Act and in this section. Capacity means the volume of liquid... or emptying means the partial or complete removal of stored liquid from a storage vessel. Storage vessels that contain liquid only as wall or bottom clingage, or in pools due to bottom irregularities, are...

40 CFR 60.111a - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Storage Vessels for Petroleum Liquids for..., reservoir, or container used for the storage of petroleum liquids, but does not include: (1) Pressure... tanks if the total volume of petroleum liquids added to and taken from a tank annually does not exceed...

40 CFR 63.1061 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... shall have the meaning given them in the Act and in this section. Capacity means the volume of liquid... or emptying means the partial or complete removal of stored liquid from a storage vessel. Storage vessels that contain liquid only as wall or bottom clingage, or in pools due to bottom irregularities, are...

40 CFR 63.1061 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... shall have the meaning given them in the Act and in this section. Capacity means the volume of liquid... or emptying means the partial or complete removal of stored liquid from a storage vessel. Storage vessels that contain liquid only as wall or bottom clingage, or in pools due to bottom irregularities, are...

40 CFR 60.111a - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Storage Vessels for Petroleum Liquids for..., reservoir, or container used for the storage of petroleum liquids, but does not include: (1) Pressure... tanks if the total volume of petroleum liquids added to and taken from a tank annually does not exceed...

40 CFR 63.1061 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... shall have the meaning given them in the Act and in this section. Capacity means the volume of liquid... or emptying means the partial or complete removal of stored liquid from a storage vessel. Storage vessels that contain liquid only as wall or bottom clingage, or in pools due to bottom irregularities, are...

40 CFR 60.111a - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Storage Vessels for Petroleum Liquids for..., reservoir, or container used for the storage of petroleum liquids, but does not include: (1) Pressure... tanks if the total volume of petroleum liquids added to and taken from a tank annually does not exceed...

40 CFR 63.1061 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... shall have the meaning given them in the Act and in this section. Capacity means the volume of liquid... or emptying means the partial or complete removal of stored liquid from a storage vessel. Storage vessels that contain liquid only as wall or bottom clingage, or in pools due to bottom irregularities, are...

40 CFR 60.111a - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Storage Vessels for Petroleum Liquids for..., reservoir, or container used for the storage of petroleum liquids, but does not include: (1) Pressure... tanks if the total volume of petroleum liquids added to and taken from a tank annually does not exceed...

Specific Volumes of the Zr(41.2)Ti(13.8)Cu(12.5)Ni(10.0)Be(22.5) Alloy in the Liquid, Glass, and Crystalline States

NASA Technical Reports Server (NTRS)

Ohsaka, K.; Chung, S. K.; Rhim, W. K.; Johnson, W. L.; Peker, A.; Scruggs, D.

1997-01-01

The specific volumes of the Zr(41.2)Ti(3.8)Cu(2.5)Ni(10.0)Be(22.5) alloy as a function of temperature, T, are determined by employing an image digitizing technique and numerical calculation methods applied to the electrostatically levitated spherical alloy. The linear fitting of the volumes of the alloy in the liquid, V(sub l), glass, V(sub g) and crystalline V(sub c), states in the temperature ranges shown in parentheses are V(sub l)(T) = 0.1583 + 8.877 x 10(exp -6) T(cu cm/g) (700-1300 K);V(sub g)(T) = 0.1603 + 5.528 x 10(exp -6) T (400-550 K);V(sub c)(T) = 0.1583 + 6.21 x 10(exp -6)T(400-850 K). The average volume thermal expansion coefficients within the temperature ranges are determined to be 5.32, 3.39. and 3.83 x 10(exp -5) (1/K) for the liquid, glass, and crystalline states, respectively.

JANNAF 28th Propellant Development and Characterization Subcommittee and 17th Safety and Environmental Protection Subcommittee Joint Meeting. Volume 1

NASA Technical Reports Server (NTRS)

Cocchiaro, James E. (Editor); Mulder, Edwin J. (Editor); Gomez-Knight, Sylvia J. (Editor)

1999-01-01

This volume contains 37 unclassified/unlimited-distribution technical papers that were presented at the JANNAF 28th Propellant Development & Characterization Subcommittee (PDCS) and 17th Safety & Environmental Protection Subcommittee (S&EPS) Joint Meeting, held 26-30 April 1999 at the Town & Country Hotel and the Naval Submarine Base, San Diego, California. Volume II contains 29 unclassified/limited-distribution papers that were presented at the 28th PDCS and 17th S&EPS Joint Meeting. Volume III contains a classified paper that was presented at the 28th PDCS Meeting on 27 April 1999. Topics covered in PDCS sessions include: solid propellant rheology; solid propellant surveillance and aging; propellant process engineering; new solid propellant ingredients and formulation development; reduced toxicity liquid propellants; characterization of hypergolic propellants; and solid propellant chemical analysis methods. Topics covered in S&EPS sessions include: space launch range safety; liquid propellant hazards; vapor detection methods for toxic propellant vapors and other hazardous gases; toxicity of propellants, ingredients, and propellant combustion products; personal protective equipment for toxic liquid propellants; and demilitarization/treatment of energetic material wastes.

Drop-on-demand sample introduction system coupled with the flowing atmospheric-pressure afterglow for direct molecular analysis of complex liquid micro-volume samples

PubMed Central

Schaper, J. Niklas; Pfeuffer, Kevin P.; Shelley, Jacob T.; Bings, Nicolas H.

2012-01-01

One of the fastest developing fields in analytical spectrochemistry in recent years is ambient desorption/ionization mass spectrometry (ADI-MS). This burgeoning interest has been due to the demonstrated advantages of the method: simple mass spectra, little or no sample preparation, and applicability to samples in the solid, liquid, or gaseous state. One such ADI-MS source, the flowing atmospheric-pressure afterglow (FAPA), is capable of direct analysis of solids just by aiming the source at the solid surface and sampling the produced ions into a mass spectrometer. However, direct introduction of significant volumes of liquid samples into this source has not been possible, as solvent loads can quench the afterglow and, thus, the formation of reagent ions. As a result, the analysis of liquid samples is preferably carried out by analyzing dried residues or by desorbing small amounts of liquid samples directly from the liquid surface. In the former case, reproducibility of sample introduction is crucial if quantitative results are desired. In the present study, introduction of liquid samples as very small droplets helps overcome the issues of sample positioning and reduced levels of solvent intake. A recently developed “drop-on-demand” (DOD) aerosol generator is capable of reproducibly producing very small volumes of liquid (~17 pL). In this paper, the coupling of FAPA-MS and DOD is reported and applications are suggested. Analytes representing different classes of substances were tested and limits of detections were determined. Matrix tolerance was investigated for drugs of abuse and their metabolites by analyzing raw urine samples and quantification without the use of internal standards. Limits of detection below 2 µg/mL, without sample pretreatment, were obtained. PMID:23025277

Three-dimensional (3D) evaluation of liquid distribution in shake flask using an optical fluorescence technique.

PubMed

Azizan, Amizon; Büchs, Jochen

2017-01-01

Biotechnological development in shake flask necessitates vital engineering parameters e.g. volumetric power input, mixing time, gas liquid mass transfer coefficient, hydromechanical stress and effective shear rate. Determination and optimization of these parameters through experiments are labor-intensive and time-consuming. Computational Fluid Dynamics (CFD) provides the ability to predict and validate these parameters in bioprocess engineering. This work provides ample experimental data which are easily accessible for future validations to represent the hydrodynamics of the fluid flow in the shake flask. A non-invasive measuring technique using an optical fluorescence method was developed for shake flasks containing a fluorescent solution with a waterlike viscosity at varying filling volume (V L  = 15 to 40 mL) and shaking frequency ( n  = 150 to 450 rpm) at a constant shaking diameter (d o  = 25 mm). The method detected the leading edge (LB) and tail of the rotating bulk liquid (TB) relative to the direction of the centrifugal acceleration at varying circumferential heights from the base of the shake flask. The determined LB and TB points were translated into three-dimensional (3D) circumferential liquid distribution plots. The maximum liquid height (H max ) of the bulk liquid increased with increasing filling volume and shaking frequency of the shaking flask, as expected. The toroidal shapes of LB and TB are clearly asymmetrical and the measured TB differed by the elongation of the liquid particularly towards the torus part of the shake flask. The 3D liquid distribution data collected at varying filling volume and shaking frequency, comprising of LB and TB values relative to the direction of the centrifugal acceleration are essential for validating future numerical solutions using CFD to predict vital engineering parameters in shake flask.

Control of ice chromatographic retention mechanism by changing temperature and dopant concentration.

PubMed

Tasaki, Yuiko; Okada, Tetsuo

2011-12-15

A liquid phase coexists with solid water ice in a typical binary system, such as NaCl-water, in the temperature range between the freezing point and the eutectic point (t(eu)) of the system. In ice chromatography with salt-doped ice as the stationary phase, both solid and liquid phase can contribute to solute retention in different fashions; that is, the solid ice surface acts as an adsorbent, while a solute can be partitioned into the liquid phase. Thus, both adsorption and partition mechanisms can be utilized for ice chromatographic separation. An important feature in this approach is that the liquid phase volume can be varied by changing the temperature and the concentration of a salt incorporated into the ice stationary phase. Thus, we can control the relative contribution from the partition mechanism in the entire retention because the liquid phase volume can be estimated from the freezing depression curve. Separation selectivity can thereby be modified. The applicability of this concept has been confirmed for the solutes of different adsorption and partition abilities. The predicted retention based on thermodynamics basically agrees well with the corresponding experimental retention. However, one important inconsistency has been found. The calculation predicts a step-like discontinuity of the solute retention at t(eu) because the phase diagram suggests that the liquid phase abruptly appears at t(eu) when the temperature increases. In contrast, the corresponding experimental plots are continuous over the wider range including the subeutectic temperatures. This discrepancy is explained by the existence of the liquid phase below t(eu). A difference between predicted and measured retention factors allows the estimation of the volume of the subeutectic liquid phase.

Materials Characterisation and Analysis for Flow Simulation of Liquid Resin Infusion

NASA Astrophysics Data System (ADS)

Sirtautas, J.; Pickett, A. K.; George, A.

2015-06-01

Liquid Resin Infusion (LRI) processes including VARI and VARTM have received increasing attention in recent years, particularly for infusion of large parts, or for low volume production. This method avoids the need for costly matched metal tooling as used in Resin Transfer Moulding (RTM) and can provide fast infusion if used in combination with flow media. Full material characterisation for LRI analysis requires models for three dimensional fabric permeability as a function of fibre volume content, fabric through-thickness compliance as a function of resin pressure, flow media permeability and resin viscosity. The characterisation of fabric relaxation during infusion is usually determined from cyclic compaction tests on saturated fabrics. This work presents an alternative method to determine the compressibility by using LRI flow simulation and fitting a model to experimental thickness measurements during LRI. The flow media is usually assumed to have isotropic permeability, but this work shows greater simulation accuracy from combining the flow media with separation plies as a combined orthotropic material. The permeability of this combined media can also be determined by fitting the model with simulation to LRI flow measurements. The constitutive models and the finite element solution were validated by simulation of the infusion of a complex aerospace demonstrator part.

Drop size distributions and related properties of fog for five locations measured from aircraft

NASA Technical Reports Server (NTRS)

Zak, J. Allen

1994-01-01

Fog drop size distributions were collected from aircraft as part of the Synthetic Vision Technology Demonstration Program. Three west coast marine advection fogs, one frontal fog, and a radiation fog were sampled from the top of the cloud to the bottom as the aircraft descended on a 3-degree glideslope. Drop size versus altitude versus concentration are shown in three dimensional plots for each 10-meter altitude interval from 1-minute samples. Also shown are median volume radius and liquid water content. Advection fogs contained the largest drops with median volume radius of 5-8 micrometers, although the drop sizes in the radiation fog were also large just above the runway surface. Liquid water content increased with height, and the total number of drops generally increased with time. Multimodal variations in number density and particle size were noted in most samples where there was a peak concentration of small drops (2-5 micrometers) at low altitudes, midaltitude peak of drops 5-11 micrometers, and high-altitude peak of the larger drops (11-15 micrometers and above). These observations are compared with others and corroborate previous results in fog gross properties, although there is considerable variation with time and altitude even in the same type of fog.

Differential solvation of intrinsically disordered linkers drives the formation of spatially organized droplets in ternary systems of linear multivalent proteins

NASA Astrophysics Data System (ADS)

Harmon, Tyler S.; Holehouse, Alex S.; Pappu, Rohit V.

2018-04-01

Intracellular biomolecular condensates are membraneless organelles that encompass large numbers of multivalent protein and nucleic acid molecules. The bodies assemble via a combination of liquid–liquid phase separation and gelation. A majority of condensates included multiple components and show multilayered organization as opposed to being well-mixed unitary liquids. Here, we put forward a simple thermodynamic framework to describe the emergence of spatially organized droplets in multicomponent systems comprising of linear multivalent polymers also known as associative polymers. These polymers, which mimic proteins and/or RNA have the architecture of domains or motifs known as stickers that are interspersed by flexible spacers known as linkers. Using a minimalist numerical model for a four-component system, we have identified features of linear multivalent molecules that are necessary and sufficient for generating spatially organized droplets. We show that differences in sequence-specific effective solvation volumes of disordered linkers between interaction domains enable the formation of spatially organized droplets. Molecules with linkers that are preferentially solvated are driven to the interface with the bulk solvent, whereas molecules that have linkers with negligible effective solvation volumes form cores in the core–shell architectures that emerge in the minimalist four-component systems. Our modeling has relevance for understanding the physical determinants of spatially organized membraneless organelles.

Nonlinear saturation of the Rayleigh instability due to oscillatory flow in a liquid-lined tube

NASA Astrophysics Data System (ADS)

Halpern, David; Grotberg, James B.

2003-10-01

In this paper, the stability of core annular flows consisting of two immiscible fluids in a cylindrical tube with circular cross-section is examined. Such flows are important in a wide range of industrial and biomedical applications. For example, in secondary oil recovery, water is pumped into the well to displace the remaining oil. It is also of relevance in the lung, where a thin liquid film coats the inner surface of the small airways of the lungs. In both cases, the flow is influenced by a surface-tension instability, which may induce the breakup of the core fluid into short plugs, reducing the efficiency of the oil recovery, or blocking the passage of air in the lung thus inducing airway closure. We consider the stability of a thin film coating the inner surface of a rigid cylindrical tube with the less viscous fluid in the core. For thick enough films, the Rayleigh instability forms a liquid bulge that can grow to eventually create a plug blocking the tube. The analysis explores the effect of an oscillatory core flow on the interfacial dynamics and particularly the nonlinear stabilization of the bulge. The oscillatory core flow exerts tangential and normal stresses on the interface between the two fluids that are simplified by uncoupling the core and film analyses in the thin-film high-frequency limit of the governing equations. Lubrication theory is used to derive a nonlinear evolution equation for the position of the air liquid interface which includes the effects of the core flow. It is shown that the core flow can prevent plug formation of the more viscous film layer by nonlinear saturation of the capillary instability. The stabilization mechanism is similar to that of a reversing butter knife, where the core shear wipes the growing liquid bulge back on to the tube wall during the main tidal volume stroke, but allows it to grow back as the stoke and shear turn around. To be successful, the leading film thickness ahead of the bulge must be smaller than the trailing film thickness behind it, a requirement necessitating a large enough core capillary number which promotes a large core shear stress on the interface. The core capillary number is defined to be the ratio of core viscous forces to surface tension forces. When this process is tuned correctly, the two phases balance and there is no net growth of the liquid bulge over one cycle. We find that there is a critical frequency above which plug formation does not occur, and that this critical frequency increases as the tidal volume amplitude of the core flow decreases.

Ionic liquid-based microwave-assisted dispersive liquid-liquid microextraction and derivatization of sulfonamides in river water, honey, milk, and animal plasma.

PubMed

Xu, Xu; Su, Rui; Zhao, Xin; Liu, Zhuang; Zhang, Yupu; Li, Dan; Li, Xueyuan; Zhang, Hanqi; Wang, Ziming

2011-11-30

The ionic liquid-based microwave-assisted dispersive liquid-liquid microextraction (IL-based MADLLME) and derivatization was applied for the pretreatment of six sulfonamides (SAs) prior to the determination by high-performance liquid chromatography (HPLC). By adding methanol (disperser), fluorescamine solution (derivatization reagent) and ionic liquid (extraction solvent) into sample, extraction, derivatization, and preconcentration were continuously performed. Several experimental parameters, such as the type and volume of extraction solvent, the type and volume of disperser, amount of derivatization reagent, microwave power, microwave irradiation time, pH of sample solution, and ionic strength were investigated and optimized. When the microwave power was 240 W, the analytes could be derivatized and extracted simultaneously within 90 s. The proposed method was applied to the analysis of river water, honey, milk, and pig plasma samples, and the recoveries of analytes obtained were in the range of 95.0-110.8, 95.4-106.3, 95.0-108.3, and 95.7-107.7, respectively. The relative standard deviations varied between 1.5% and 7.3% (n=5). The results showed that the proposed method was a rapid, convenient and feasible method for the determination of SAs in liquid samples. Copyright © 2011 Elsevier B.V. All rights reserved.

Penetration and blown-air effect in sand

NASA Astrophysics Data System (ADS)

Clement, R.; Courrech du Pont, S.; Douady, S.

2012-04-01

Sand is known to show a variety of uncommon physical features that do not fit the behavior of liquid or solid state. A good example of the inherent difficulties encountered when trying to describe collective grains behavior is the penetration of an intruding object into a granular medium. Such problems involve large coordination numbers, and the medium response dramatically depends on the volume fraction. On the fringe of these studies, we consider here the penetration of a cylindrical shell (typically an upside down glass) into dry sand, and report what we called the "blown-air effect". The air initially trapped escapes when the shell is pushed into sand, flowing through the granular medium. This flow dilates the sand and considerably eases the penetration of the shell. This is very different from what happens in liquids: when pushing a top-closed shell into a liquid, the trapped air increases the buoyancy and opposes the penetration. We show that the air flow does not change the general dynamics of penetration, suggesting that fluidization only involves an effective smaller volume fraction. Despite its simplicity (only a glass and some sand are needed to observe the effect), this experiment nicely illustrates the sometimes counter-intuitive behavior of granular media. Penetration in sand is also a critical issue in industry, and this work may help improving burying methods. Ref: Penetration and blown air effect in granular media R. Clément, S. Courrech du Pont, M. Ould-Hamouda, D. Duveau, and S. Douady Phys. Rev. Lett. 2011 Science News: http://news.sciencemag.org/sciencenow/2011/02/convince-your-friends-youre-a-ge.html

Effect of extra-column volume on practical chromatographic parameters of sub-2-μm particle-packed columns in ultra-high pressure liquid chromatography.

PubMed

Wu, Naijun; Bradley, Ashley C; Welch, Christopher J; Zhang, Li

2012-08-01

Effects of extra-column volume on apparent separation parameters were studied in ultra-high pressure liquid chromatography with columns and inlet connection tubings of various internal diameters (id) using 50-mm long columns packed with 1.8-μm particles under isocratic conditions. The results showed that apparent retention factors were on average 5, 11, 18, and 41% lower than those corrected with extra-column volumes for 4.6-, 3.0-, 2.1-, and 1.0-mm id columns, respectively, when the extra-column volume (11.3 μL) was kept constant. Also, apparent pressures were 31, 16, 12, and 10% higher than those corrected with pressures from extra-column volumes for 4.6-, 3.0-, 2.1-, and 1.0-mm id columns at the respective optimum flow rate for a typical ultra-high pressure liquid chromatography system. The loss in apparent efficiency increased dramatically from 4.6- to 3.0- to 2.1- to 1.0-mm id columns, less significantly as retention factors increased. The column efficiency was significantly improved as the inlet tubing id was decreased for a given column. The results suggest that maximum ratio of extra-column volume to column void volume should be approximately 1:10 for column porosity more than 0.6 and a retention factor more than 5, where 80% or higher of theoretically predicted efficiency could be achieved. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Serrating Nozzle Surfaces for Complete Transfer of Droplets

NASA Technical Reports Server (NTRS)

Kim, Chang-Jin " CJ" ; Yi, Uichong

2010-01-01

A method of ensuring the complete transfer of liquid droplets from nozzles in microfluidic devices to nearby surfaces involves relatively simple geometric modification of the nozzle surfaces. The method is especially applicable to nozzles in print heads and similar devices required to dispense liquid droplets having precise volumes. Examples of such devices include heads for soft printing of ink on paper and heads for depositing droplets of deoxyribonucleic acid (DNA) or protein solutions on glass plates to form microarrays of spots for analysis. The main purpose served by the present method is to ensure that droplets transferred from a nozzle have consistent volume, as needed to ensure accuracy in microarray analysis or consistent appearance of printed text and images. In soft printing, droplets having consistent volume are generated inside a print head, but in the absence of the present method, the consistency is lost in printing because after each printing action (in which a drop is ejected from a nozzle), a small residual volume of liquid remains attached to the nozzle. By providing for complete transfer of droplets (and thus eliminating residual liquid attached to the nozzle) the method ensures consistency of volume of transferred droplets. An additional benefit of elimination of residue is prevention of cross-contamination among different liquids printed through the same nozzle a major consideration in DNA microarray analysis. The method also accelerates the printing process by minimizing the need to clean a printing head to prevent cross-contamination. Soft printing involves a hydrophobic nozzle surface and a hydrophilic print surface. When the two surfaces are brought into proximity such that a droplet in the nozzle makes contact with the print surface, a substantial portion of the droplet becomes transferred to the print surface. Then as the nozzle and the print surface are pulled apart, the droplet is pulled apart and most of the droplet remains on the print surface. The basic principle of the present method is to reduce the liquid-solid surface energy of the nozzle to a level sufficiently below the intrinsic solid-liquid surface energy of the nozzle material so that the droplet is not pulled apart and, instead, the entire droplet volume becomes transferred to the print surface. In this method, the liquid-solid surface energy is reduced by introducing artificial surface roughness in the form of micromachined serrations on the inner nozzle surface (see figure). The method was tested in experiments on soft printing of DNA solutions and of deionized water through 0.5-mm-diameter nozzles, of which some were not serrated, some were partially serrated, and some were fully serrated. In the nozzles without serrations, transfer was incomplete; that is, residual liquids remained in the nozzles after printing. However, in every nozzle in which at least half the inner surface was serrated, complete transfer of droplets to the print surface was achieved.

Liquid rocket booster integration study. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1988-01-01

The impacts of introducing liquid rocket booster engines (LRB) into the Space Transportation System (STS)/Kennedy Space Center (KSC) launch environment are identified and evaluated. Proposed ground systems configurations are presented along with a launch site requirements summary. Prelaunch processing scenarios are described and the required facility modifications and new facility requirements are analyzed. Flight vehicle design recommendations to enhance launch processing are discussed. Processing approaches to integrate LRB with existing STS launch operations are evaluated. The key features and significance of launch site transition to a new STS configuration in parallel with ongoing launch activities are enumerated. This volume is the executive summary of the five volume series.

Liquid rocket booster integration study. Volume 5, part 1: Appendices

NASA Technical Reports Server (NTRS)

1988-01-01

The impacts of introducing liquid rocket booster engines (LRB) into the Space Transportation System (STS)/Kennedy Space Center (KSC) launch environment are identified and evaluated. Proposed ground systems configurations are presented along with a launch site requirements summary. Prelaunch processing scenarios are described and the required facility modifications and new facility requirements are analyzed. Flight vehicle design recommendations to enhance launch processing are discussed. Processing approaches to integrate LRB with existing STS launch operations are evaluated. The key features and significance of launch site transition to a new STS configuration in parallel with ongoing launch activities are enumerated. This volume is the appendices of the five volume series.

Liquid Rocket Booster Integration Study. Volume 2: Study synopsis

NASA Technical Reports Server (NTRS)

1988-01-01

The impacts of introducing liquid rocket booster engines (LRB) into the Space Transportation System (STS)/Kennedy Space Center (KSC) launch environment are identified and evaluated. Proposed ground systems configurations are presented along with a launch site requirements summary. Prelaunch processing scenarios are described and the required facility modifications and new facility requirements are analyzed. Flight vehicle design recommendations to enhance launch processing are discussed. Processing approaches to integrate LRB with existing STS launch operations are evaluated. The key features and significance of launch site transition to a new STS configuration in parallel with ongoing launch activities are enumerated. This volume is the study summary of the five volume series.

JANNAF 36th Combustion Subcommittee Meeting. Volume 2

NASA Technical Reports Server (NTRS)

Fry, Ronald S. (Editor); Gannaway, Mary T. (Editor)

1999-01-01

Volume 11, the second of three volumes is a compilation of 33 unclassified/unlimited-distribution technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 36th Combustion Subcommittee held jointly with the 24 Airbreathing Propulsion Subcommittee and 18th Propulsion Systems Hazards Subcommittee. The meeting was held on 18-21 October 1999 at NASA Kennedy Space Center and The DoubleTree Oceanfront Hotel, Cocoa Beach, Florida. Topics covered include gun solid propellant ignition and combustion, Electrothermal Chemical (ETC) propulsion phenomena, liquid propellant gun combustion and barrel erosion, gas phase propellant combustion, kinetic and decomposition phenomena and liquid and hybrid propellant combustion behavior.

Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program, FY-98 Status Report

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

Herbst, A.K.; Rogers, A.Z.; McCray, J.A.

The Low-Activity Waste Process Technology Program at the Idaho Nuclear Technology and Engineering Center (INTEC) anticipates that large volumes of low-level/low-activity wastes will need to be grouted prior to near-surface disposal. During fiscal year 1998, three grout formulations were studied for low-activity wastes derived from INTEC liquid sodium-bearing waste. Compressive strength and leach results are presented for phosphate bonding cement, acidic grout, and alkaline grout formulations. In an additional study, grout formulations are recommended for stabilization of the INTEC underground storage tank residual heels.

Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE): Conceptual Design Report. Volume 1: The LBNF and DUNE Projects

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

Acciarri, R.

2016-01-22

This document presents the Conceptual Design Report (CDR) put forward by an international neutrino community to pursue the Deep Underground Neutrino Experiment at the Long-Baseline Neutrino Facility (LBNF/DUNE), a groundbreaking science experiment for long-baseline neutrino oscillation studies and for neutrino astrophysics and nucleon decay searches. The DUNE far detector will be a very large modular liquid argon time-projection chamber (LArTPC) located deep underground, coupled to the LBNF multi-megawatt wide-band neutrino beam. DUNE will also have a high-resolution and high-precision near detector.

Microspherical photonics: Sorting resonant photonic atoms by using light

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

Maslov, Alexey V., E-mail: avmaslov@yandex.ru; Astratov, Vasily N., E-mail: astratov@uncc.edu

2014-09-22

A method of sorting microspheres by resonant light forces in vacuum, air, or liquid is proposed. Based on a two-dimensional model, it is shown that the sorting can be realized by allowing spherical particles to traverse a focused beam. Under resonance with the whispering gallery modes, the particles acquire significant velocity along the beam direction. This opens a unique way of large-volume sorting of nearly identical photonic atoms with 1/Q accuracy, where Q is the resonance quality factor. This is an enabling technology for developing super-low-loss coupled-cavity structures and devices.

Laser Processed Heat Exchangers

NASA Technical Reports Server (NTRS)

Hansen, Scott

2017-01-01

The Laser Processed Heat Exchanger project will investigate the use of laser processed surfaces to reduce mass and volume in liquid/liquid heat exchangers as well as the replacement of the harmful and problematic coatings of the Condensing Heat Exchangers (CHX). For this project, two scale unit test articles will be designed, manufactured, and tested. These two units are a high efficiency liquid/liquid HX and a high reliability CHX.

Surface Tension Confines Cryogenic Liquid

NASA Technical Reports Server (NTRS)

Castles, Stephen H.; Schein, Michael E.

1989-01-01

New type of Dewar provides passive, constant-temperature cryogenic cooling for scientific instruments under normal-to low-gravity conditions. Known as Surface-Tension-Contained Liquid Cryogen Cooler (STCLCC), keeps liquid cryogen in known location inside the Dewar by trapping liquid inside spongelike material. Unique sponge material fills most of volume of inner tank. Sponge is all-silica, open-cell material similar to that used for Space Shuttle thermal-protection tiles.

The influence of trading volume on market efficiency: The DCCA approach

NASA Astrophysics Data System (ADS)

Sukpitak, Jessada; Hengpunya, Varagorn

2016-09-01

For a single market, the cross-correlation between market efficiency and trading volume, which is an indicator of market liquidity, is attentively analysed. The study begins with creating time series of market efficiency by applying time-varying Hurst exponent with one year sliding window to daily closing prices. The time series of trading volume corresponding to the same time period used for the market efficiency is derived from one year moving average of daily trading volume. Subsequently, the detrended cross-correlation coefficient is employed to quantify the degree of cross-correlation between the two time series. It was found that values of cross-correlation coefficient of all considered stock markets are close to 0 and are clearly out of range in which correlation being considered significant in almost every time scale. Obtained results show that the market liquidity in term of trading volume hardly has effect on the market efficiency.

Zeolite crystal growth in space

NASA Technical Reports Server (NTRS)

Sacco, Albert, Jr.; Thompson, Robert W.; Dixon, Anthony G.

1991-01-01

The growth of large, uniform zeolite crystals in high yield in space can have a major impact on the chemical process industry. Large zeolite crystals will be used to improve basic understanding of adsorption and catalytic mechanisms, and to make zeolite membranes. To grow large zeolites in microgravity, it is necessary to control the nucleation event and fluid motion, and to enhance nutrient transfer. Data is presented that suggests nucleation can be controlled using chemical compounds (e.g., Triethanolamine, for zeolite A), while not adversely effecting growth rate. A three-zone furnace has been designed to perform multiple syntheses concurrently. The operating range of the furnace is 295 K to 473 K. Teflon-lined autoclaves (10 ml liquid volume) have been designed to minimize contamination, reduce wall nucleation, and control mixing of pre-gel solutions on orbit. Zeolite synthesis experiments will be performed on USML-1 in 1992.

Studies of the limit order book around large price changes

NASA Astrophysics Data System (ADS)

Tóth, B.; Kertész, J.; Farmer, J. D.

2009-10-01

We study the dynamics of the limit order book of liquid stocks after experiencing large intra-day price changes. In the data we find large variations in several microscopical measures, e.g., the volatility the bid-ask spread, the bid-ask imbalance, the number of queuing limit orders, the activity (number and volume) of limit orders placed and canceled, etc. The relaxation of the quantities is generally very slow that can be described by a power law of exponent ≈ 0.4. We introduce a numerical model in order to understand the empirical results better. We find that with a zero intelligence deposition model of the order flow the empirical results can be reproduced qualitatively. This suggests that the slow relaxations might not be results of agents' strategic behaviour. Studying the difference between the exponents found empirically and numerically helps us to better identify the role of strategic behaviour in the phenomena. in here

Drizzle formation in stratocumulus clouds: Effects of turbulent mixing

DOE PAGES

Magaritz-Ronen, L.; Pinsky, M.; Khain, A.

2016-02-17

The mechanism of drizzle formation in shallow stratocumulus clouds and the effect of turbulent mixing on this process are investigated. A Lagrangian–Eularian model of the cloud-topped boundary layer is used to simulate the cloud measured during flight RF07 of the DYCOMS-II field experiment. The model contains ~ 2000 air parcels that are advected in a turbulence-like velocity field. In the model all microphysical processes are described for each Lagrangian air volume, and turbulent mixing between the parcels is also taken into account. It was found that the first large drops form in air volumes that are closest to adiabatic andmore » characterized by high humidity, extended residence near cloud top, and maximum values of liquid water content, allowing the formation of drops as a result of efficient collisions. The first large drops form near cloud top and initiate drizzle formation in the cloud. Drizzle is developed only when turbulent mixing of parcels is included in the model. Without mixing, the cloud structure is extremely inhomogeneous and the few large drops that do form in the cloud evaporate during their sedimentation. Lastly, it was found that turbulent mixing can delay the process of drizzle initiation but is essential for the further development of drizzle in the cloud.« less

Drizzle formation in stratocumulus clouds: Effects of turbulent mixing

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

Magaritz-Ronen, L.; Pinsky, M.; Khain, A.

The mechanism of drizzle formation in shallow stratocumulus clouds and the effect of turbulent mixing on this process are investigated. A Lagrangian–Eularian model of the cloud-topped boundary layer is used to simulate the cloud measured during flight RF07 of the DYCOMS-II field experiment. The model contains ~ 2000 air parcels that are advected in a turbulence-like velocity field. In the model all microphysical processes are described for each Lagrangian air volume, and turbulent mixing between the parcels is also taken into account. It was found that the first large drops form in air volumes that are closest to adiabatic andmore » characterized by high humidity, extended residence near cloud top, and maximum values of liquid water content, allowing the formation of drops as a result of efficient collisions. The first large drops form near cloud top and initiate drizzle formation in the cloud. Drizzle is developed only when turbulent mixing of parcels is included in the model. Without mixing, the cloud structure is extremely inhomogeneous and the few large drops that do form in the cloud evaporate during their sedimentation. Lastly, it was found that turbulent mixing can delay the process of drizzle initiation but is essential for the further development of drizzle in the cloud.« less

System and method for liquid silicon containment

DOEpatents

Cliber, James A; Clark, Roger F; Stoddard, Nathan G; Von Dollen, Paul

2013-05-28

This invention relates to a system and a method for liquid silicon containment, such as during the casting of high purity silicon used in solar cells or solar modules. The containment apparatus includes a shielding member adapted to prevent breaching molten silicon from contacting structural elements or cooling elements of a casting device, and a volume adapted to hold a quantity of breaching molten silicon with the volume formed by a bottom and one or more sides.

System and method for liquid silicon containment

DOEpatents

Cliber, James A; Clark, Roger F; Stoddard, Nathan G; Von Dollen, Paul

2014-06-03

This invention relates to a system and a method for liquid silicon containment, such as during the casting of high purity silicon used in solar cells or solar modules. The containment apparatus includes a shielding ember adapted to prevent breaching molten silicon from contacting structural elements or cooling elements of a casting device, and a volume adapted to hold a quantity of breaching molten silicon with the volume formed by a bottom and one or more sides.

Nanoparticle enhanced ionic liquid heat transfer fluids

DOEpatents

Fox, Elise B.; Visser, Ann E.; Bridges, Nicholas J.; Gray, Joshua R.; Garcia-Diaz, Brenda L.

2014-08-12

A heat transfer fluid created from nanoparticles that are dispersed into an ionic liquid is provided. Small volumes of nanoparticles are created from e.g., metals or metal oxides and/or alloys of such materials are dispersed into ionic liquids to create a heat transfer fluid. The nanoparticles can be dispersed directly into the ionic liquid during nanoparticle formation or the nanoparticles can be formed and then, in a subsequent step, dispersed into the ionic liquid using e.g., agitation.

Draft Tube Baffle (DTB) crystallizers: A study of stationary and dynamically behaving Crystal Size Distributions (CSD)

NASA Astrophysics Data System (ADS)

Deleer, B. G. M.

1981-11-01

Based on population balance, CSD behavior as a function of geometrical and operating variables was studied, using a crystallizer. A potash alum-water system, involving a separation technique which uses surface active agents and an apolar, organic liquid to separate potash alum crystals from mother liquid under the influence of gravity was used to check experimental findings against literature data. Results show action of annular settling spaces is strongly influenced by fluid velocities perpendicular to those directed upwards. The well-mixed volume decreases with increasing crystallizer size until a minimum effective volume is reached. As supersaturation is constant throughout the crystallizer volume under stationary operating conditions, the annular settling space behaves like a growth chamber for crystals in its volume. Swirl in the lower part of the annular volume introduces significant back mixing. Crystals within this space either grow and return to the well-mixed part, or withdraw from the annular volume permanently.

Determination of void volume in normal phase liquid chromatography.

PubMed

Jiang, Ping; Wu, Di; Lucy, Charles A

2014-01-10

Void volume is an important fundamental parameter in chromatography. Little prior discussion has focused on the determination of void volume in normal phase liquid chromatography (NPLC). Various methods to estimate the total void volume are compared: pycnometry; minor disturbance method based on injection of weak solvent; tracer pulse method; hold-up volume based on unretained compounds; and accessible volume based on Martin's rule and its descendants. These are applied to NPLC on silica, RingSep and DNAP columns. Pycnometry provides a theoretically maximum value for the total void volume and should be performed at least once for each new column. However, pycnometry does not reflect the volume of adsorbed strong solvent on the stationary phase, and so only yields an accurate void volume for weaker mobile phase conditions. 1,3,5-Tri-t-butyl benzene (TTBB) results in hold-up volumes that are convenient measures of the void volume for all eluent conditions on charge-transfer columns (RingSep and DNAP), but is weakly retained under weak eluent conditions on silica. Injection of the weak mobile phase component (hexane) may be used to determine void volume, but care must be exercised to select the appropriate disturbance feature. Accessible volumes, that are determined using a homologous series, are always biased low, and are not recommended as a measure of the void volume. Copyright © 2013 Elsevier B.V. All rights reserved.