Design and dynamic modeling of electrorheological fluid-based variable-stiffness fin for robotic fish

NASA Astrophysics Data System (ADS)

Bazaz Behbahani, Sanaz; Tan, Xiaobo

2017-08-01

Fish actively control their stiffness in different swimming conditions. Inspired by such an adaptive behavior, in this paper we study the design, prototyping, and dynamic modeling of compact, tunable-stiffness fins for robotic fish, where electrorheological (ER) fluid serves as the enabling element. A multi-layer composite fin with an ER fluid core is prototyped and utilized to investigate the influence of electrical field on its performance. Hamilton's principle is used to derive the dynamic equations of motion of the flexible fin, and Lighthill's large-amplitude elongated-body theory is adopted to estimate the hydrodynamic force when the fin undergoes base-actuated rotation. The dynamic equations are then discretized using the finite element method, to obtain an approximate numerical solution. Experiments are conducted on the prototyped flexible ER fluid-filled beam for parameter identification and validation of the proposed model, and for examining the effectiveness of electrically controlled stiffness tuning. In particular, it is found that the natural frequency is increased by almost 40% when the applied electric field changes from 0 to 1.5× {10}6 {{V}} {{{m}}}-1.

Fabrication of poly(o-anisidine) coated silica core-shell microspheres and their electrorheological response

NASA Astrophysics Data System (ADS)

Lee, Chul Joo; Choi, Hyoung Jin

2017-11-01

In this work, silica/poly(o-anisidine) (POA) core-shell structured microspheres were synthesized by coating the silica core surface with POA with a help of a chemical grafting agent, N-[(3-trimethoxylsilyl)-propyl] aniline. The synthesized silica microspheres were then applied as a polymer/inorganic composite particle-based electrorheological (ER) fluid. The morphology of the silica/POA microspheres was examined by using both transmission electron microscopy and scanning electron microscopy, while their thermal properties and chemical structure were checked by thermogravimetric analysis and Fourier-transform infrared spectroscopy, respectively. The ER properties of the silica/POA particle-based ER fluid were examined by using a Couette-type rotational rheometer equipped with a high-voltage power supplier and analyzed by the Bingham model and modified Mason number. In order to obtain additional information about the electrical polarization properties, the dielectric spectra were measured by an LCR meter and fitted by using the Cole-Cole equation. Furthermore, suspension stability of the ER fluid was tested using Turbiscan.

Electrorheological Fluids with High Shear Stress Based on Wrinkly Tin Titanyl Oxalate.

PubMed

Wu, Jinghua; Zhang, Lei; Xin, Xing; Zhang, Yang; Wang, Hui; Sun, Aihua; Cheng, Yuchuan; Chen, Xinde; Xu, Gaojie

2018-02-21

Electrorheological (ER) fluids are considered as a type of smart fluids because their rheological characteristics can be altered through an electric field. The discovery of giant ER effect revived the researchers' interest in the ER technological area. However, the poor stability including the insufficient dynamic shear stress, the large leakage current density, and the sedimentation tendency still hinders their practical applications. Herein, we report a facile and scalable coprecipitation method for synthesizing surfactant-free tin titanyl oxalate (TTO) particles with tremella-like wrinkly microstructure (W-TTO). The W-TTO-based ER fluids exhibit enhanced ER activity compared to that of the pristine TTO because of the improved wettability between W-TTO and the silicone oil. In addition, the static yield stress and leakage current of W-TTO ER fluids also show a fine time stability during the 30 day tests. More importantly, the dynamic shear stress of W-TTO ER fluids can remain stable throughout the shear rate range, which is valuable for their use in engineering applications. The results in this work provided a promising strategy to solving the long-standing problem of ER fluid stability. Moreover, this convenient route of synthesis may be considered a green approach for the mass production of giant ER materials.

Shocking chocolate into shape

NASA Astrophysics Data System (ADS)

Ornes, Stephen

2016-11-01

Wouldn't you love chocolate to have less fat but all the taste? Stephen Ornes discovers how the study of electrorheological fluids has led one physicist to a develop a new way to trim the fat from chocolate

Electrorheological (ER) Fluids: A Research Needs Assessment

DTIC Science & Technology

1993-05-01

transmission, and to reduce energy loss and damage due to vibration and oscillation. A large number and variety of ER devices have been invented; they are...suspension must be stabilized to prevent settling. Separation could cause loss of fluid performance, plugging of flow paths, and other problems...performa.ice of ER fluids, especially those containing water, can change with time as a result of component loss through evaporation at elevated use

Acoustical scattering by multilayer spherical elastic scatterer containing electrorheological layer.

PubMed

Cai, Liang-Wu; Dacol, Dacio K; Orris, Gregory J; Calvo, David C; Nicholas, Michael

2011-01-01

A computational procedure for analyzing acoustical scattering by multilayer concentric spherical scatterers having an arbitrary mixture of acoustic and elastic materials is proposed. The procedure is then used to analyze the scattering by a spherical scatterer consisting of a solid shell and a solid core encasing an electrorheological (ER) fluid layer, and the tunability in the scattering characteristics afforded by the ER layer is explored numerically. Tunable scatterers with two different ER fluids are analyzed. One, corn starch in peanut oil, shows that a significant increase in scattering cross-section is possible in moderate frequencies. Another, fine poly-methyl methacrylate (PMMA) beads in dodecane, shows only slight change in scattering cross-sections overall. But, when the shell is thin, a noticeable local resonance peak can appear near ka=1, and this resonance can be turned on or off by the external electric field.

Control of electro-rheological fluid-based torque generation components for use in active rehabilitation devices

NASA Astrophysics Data System (ADS)

Nikitczuk, Jason; Weinberg, Brian; Mavroidis, Constantinos

2006-03-01

In this paper we present the design and control algorithms for novel electro-rheological fluid based torque generation elements that will be used to drive the joint of a new type of portable and controllable Active Knee Rehabilitation Orthotic Device (AKROD) for gait retraining in stroke patients. The AKROD is composed of straps and rigid components for attachment to the leg, with a central hinge mechanism where a gear system is connected. The key features of AKROD include: a compact, lightweight design with highly tunable torque capabilities through a variable damper component, full portability with on board power, control circuitry, and sensors (encoder and torque), and real-time capabilities for closed loop computer control for optimizing gait retraining. The variable damper component is achieved through an electro-rheological fluid (ERF) element that connects to the output of the gear system. Using the electrically controlled rheological properties of ERFs, compact brakes capable of supplying high resistive and controllable torques, are developed. A preliminary prototype for AKROD v.2 has been developed and tested in our laboratory. AKROD's v.2 ERF resistive actuator was tested in laboratory experiments using our custom made ERF Testing Apparatus (ETA). ETA provides a computer controlled environment to test ERF brakes and actuators in various conditions and scenarios including emulating the interaction between human muscles involved with the knee and AKROD's ERF actuators / brakes. In our preliminary results, AKROD's ERF resistive actuator was tested in closed loop torque control experiments. A hybrid (non-linear, adaptive) Proportional-Integral (PI) torque controller was implemented to achieve this goal.

Characteristics of an electro-rheological fluid valve used in an inkjet printhead

NASA Astrophysics Data System (ADS)

Lee, C. Y.; Liao, W. C.

2000-12-01

The demand for non-impact printers has grown considerably with the advent of personal computers. For entry-level mass production, two drop-on-demand techniques have dominated the market - piezoelectric impulse and thermal-bubble types. However, the high cost of the piezoelectric printhead and the thermal problems encountered by the thermal-bubble jet printhead have restrained the use of these techniques in an array-type printhead. In this study, we propose a new design of printhead with an electro-rheological (ER) fluid acting as a control medium. The ER fluid valve controls the ink ejection. As a first step toward developing this new printhead, the characteristics of an ER fluid valve which controls the deflection of the elastic diaphragm are investigated. First, the response of a prototype is tested experimentally to prove the feasibility of using this ER valve for the inkjet printhead. Then, the discretized governing equation of the ER valve is derived. Finally, the prototype of the ER valve is fabricated. The experimental measurement based on the sinusoidal response verifies both the theoretical analysis and the controllability of the response of the ER valve by the applied electric field.

Torque Measurement of 3-DOF Haptic Master Operated by Controllable Electrorheological Fluid

NASA Astrophysics Data System (ADS)

Oh, Jong-Seok; Choi, Seung-Bok; Lee, Yang-Sub

2015-02-01

This work presents a torque measurement method of 3-degree-of-freedom (3-DOF) haptic master featuring controllable electrorheological (ER) fluid. In order to reflect the sense of an organ for a surgeon, the ER haptic master which can generate the repulsive torque of an organ is utilized as a remote controller for a surgery robot. Since accurate representation of organ feeling is essential for the success of the robot-assisted surgery, it is indispensable to develop a proper torque measurement method of 3-DOF ER haptic master. After describing the structural configuration of the haptic master, the torque models of ER spherical joint are mathematically derived based on the Bingham model of ER fluid. A new type of haptic device which has pitching, rolling, and yawing motions is then designed and manufactured using a spherical joint mechanism. Subsequently, the field-dependent parameters of the Bingham model are identified and generating repulsive torque according to applied electric field is measured. In addition, in order to verify the effectiveness of the proposed torque model, a comparative work between simulated and measured torques is undertaken.

Viscous properties of aluminum oxide nanotubes and aluminium oxide nanoparticles - silicone oil suspensions

NASA Astrophysics Data System (ADS)

Thapa, Ram; French, Steven; Delgado, Adrian; Ramos, Carlos; Gutierrez, Jose; Chipara, Mircea; Lozano, Karen

2010-03-01

Electrorheological (ER) fluids consisting of γ-aluminum oxide nanotubes and γ-aluminum oxide nanoparticles dispersed within silicone oil were prepared. The relationship between shear stress and shear rate was measured and theoretically simulated by using an extended Bingham model for both the rheological and electrorheological features of these systems. Shear stress and viscosity showed a sharp increase for the aluminum oxide nanotubes suspensions subjected to applied electric fields whereas aluminum oxide nanoparticles suspensions showed a moderate change. It was found that the transition from liquid to solid state (mediated by the applied electric field) can be described by a power law and that for low applied voltages the relationship is almost linear.

Dissipation of Energy in a Concentric ER Clutch and its Refined Quasi-Static Model

NASA Astrophysics Data System (ADS)

Oravský, Vladimír

A concentric electrorheological clutch (ERC) constituting the central part of a broader system: electro-hydro-aggregate (EHA) with an electrodrive (ED) on one side and a loading machine (brake B) on the other side is considered. The corresponding quasi-static model (at constant load and speed) is investigated and refined by insertion of power absorbed by electrorheological fluid (ERF). This increases the number of nondimensional parameters of the model from 8 to 12. Classification of several kinds of dissipation of energy in ERC is presented. Description and analysis of dissipation of the first kind are given more in detail and illustrated by synoptical diagrams. Also two definitions of efficiency of ERC are introduced and discussed.

Feedback control of an electrorheological long-stroke vibration damper

NASA Astrophysics Data System (ADS)

Sims, Neil D.; Stanway, Roger; Johnson, Andrew R.; Peel, David J.; Bullough, William A.

1999-06-01

It is widely acknowledged that the inherent non-linearity of smart fluid dampers is inhibiting the development of effective control regimes, and mass-production devices. In an earlier publication, an innovative solution to this problem was presented -- using a simple feedback control strategy to linearize the response. The study used a quasi-steady model of a long-stroke Electrorheological damper, and showed how proportional feedback control could linearize the simulated response. However, this initial research did not consider the dynamics of the damper's behavior, and so the development of a more advanced model has been necessary. In this article, the authors present an extension to this earlier study, using a model of the damper's response that is capable of accurately predicting the dynamic response of the damper. To introduce the topic, the electrorheological long-stroke damper test rig is described, and an overview of the earlier study is given. The advanced model is then derived, and its predictions are compared to experimental data from the test rig. This model is then incorporated into the feedback control simulations, and it is shown how the control strategy is still able to linearize the response in simulations.

Stimuli-responsive polyaniline coated silica microspheres and their electrorheology

NASA Astrophysics Data System (ADS)

Park, Dae Eun; Choi, Hyoung Jin; Vu, Cuong Manh

2016-05-01

Silica/polyaniline (PANI) core-shell structured microspheres were synthesized by coating the surface of silica micro-beads with PANI and applied as a candidate inorganic/polymer composite electrorheological (ER) material. The silica micro-beads were initially modified using N-[(3-trimethoxysilyl)-propyl] aniline to activate an aniline functional group on the silica surface for a better PANI coating. The morphology of the PANI coating on the silica surface was examined by scanning electron microscopy and the silica/PANI core-shell structure was confirmed by transmission electron microscopy. The chemical structure of the particles was confirmed by Fourier transform infrared spectroscopy. Rotational rheometry was performed to confirm the difference in the ER properties between pure silica and silica/PANI microsphere-based ER fluids when dispersed in silicone oil.

Instabilities in a Relativistic Viscous Fluid

NASA Astrophysics Data System (ADS)

Corona-Galindo, M. G.; Klapp, J.; Vazquez, A.

1990-11-01

RESUMEN. Las ecuaciones hidrodinamicas de un fluido imperfecto relativista son resueltas, y los modos hidrodinamicos son analizados con el prop6sito de estabiecer correlaciones con las estructuras cosmol6gicas. ABSTRACT The hydrodynamical equations of a relativistic imperfect fluid are solved, and the hydrodynamical modes are analysed with the aim to establish correlations with cosmological structures. Ke, words: COSMOLOGY - HYDRODYNAMICS - RELATIVITY

Electro-elastoviscous response of polyaniline functionalized nano-porous zeolite based colloidal dispersions.

PubMed

Chattopadhyay, Ankur; Rani, Poonam; Srivastava, Rajendra; Dhar, Purbarun

2018-06-01

The present article discusses the typical influence of grafted conducting polymers in the mesoscale pores of dielectric particles on the static and dynamic electrorheology and electro-viscoelastic behavior of corresponding colloids. Nanocrystalline meso-nanoporous zeolite has been prepared by chemical synthesis and subsequently polyaniline (PANI) coating has been implemented. Electrorheological (ER) suspensions have been formed by dispersing the nanoparticles in silicone oil and their viscoelastic behaviors are examined to understand the nature of such complex colloidal systems under electric fields. PANI-Zeolite ER fluids demonstrate higher static electroviscous effects and yield stress potential than untreated Zeolite, typically studied in literature. Transient electro-viscous characterizations show a stable and negligible hysteresis behavior when both the fluids are exposed to constant as well as time varying electric field intensities. Further oscillatory shear experiments of frequency and strain sweeps exhibit predominant elastic behavior in case of Zeolite based ER suspensions as compared to PANI systems. Detailed investigations reveal Zeolite based ER suspensions display enhanced relative yielding as well as electro-viscoelastic stability than the PANI-Zeolite. The steady state viscous behaviors are scaled against the non-dimensional Mason number to model the system behavior for both fluids. Experimental data of flow behaviors of both the ER fluids are compared with semi-classical models and it is found that the CCJ model possesses a closer proximity than traditional Bingham model, thereby revealing the fluids to be generic pseudo-linear fluids. The present article reveals that while the PANI based fluids are typically hailed superior in literature, it is only restricted to steady shear utilities. In case of dynamic and oscillatory systems, the traditional Zeolite based fluids exhibit superior ER caliber. Copyright © 2018 Elsevier Inc. All rights reserved.

Modeling and Design of an Electro-Rheological Fluid Based Haptic System for Tele-Operation of Space Robots

NASA Technical Reports Server (NTRS)

Mavroidis, Constantinos; Pfeiffer, Charles; Paljic, Alex; Celestino, James; Lennon, Jamie; Bar-Cohen, Yoseph

2000-01-01

For many years, the robotic community sought to develop robots that can eventually operate autonomously and eliminate the need for human operators. However, there is an increasing realization that there are some tasks that human can perform significantly better but, due to associated hazards, distance, physical limitations and other causes, only robot can be employed to perform these tasks. Remotely performing these types of tasks requires operating robots as human surrogates. While current "hand master" haptic systems are able to reproduce the feeling of rigid objects, they present great difficulties in emulating the feeling of remote/virtual stiffness. In addition, they tend to be heavy, cumbersome and usually they only allow limited operator workspace. In this paper a novel haptic interface is presented to enable human-operators to "feel" and intuitively mirror the stiffness/forces at remote/virtual sites enabling control of robots as human-surrogates. This haptic interface is intended to provide human operators intuitive feeling of the stiffness and forces at remote or virtual sites in support of space robots performing dexterous manipulation tasks (such as operating a wrench or a drill). Remote applications are referred to the control of actual robots whereas virtual applications are referred to simulated operations. The developed haptic interface will be applicable to IVA operated robotic EVA tasks to enhance human performance, extend crew capability and assure crew safety. The electrically controlled stiffness is obtained using constrained ElectroRheological Fluids (ERF), which changes its viscosity under electrical stimulation. Forces applied at the robot end-effector due to a compliant environment will be reflected to the user using this ERF device where a change in the system viscosity will occur proportionally to the force to be transmitted. In this paper, we will present the results of our modeling, simulation, and initial testing of such an electrorheological fluid (ERF) based haptic device.

Electrorheological suspensions of laponite in oil: rheometry studies.

PubMed

Parmar, K P S; Méheust, Y; Schjelderupsen, Børge; Fossum, J O

2008-03-04

We have studied the effect of an external direct current (DC) electric field ( approximately 1 kV/mm) on the rheological properties of colloidal suspensions consisting of aggregates of laponite particles in a silicone oil. Microscopy observations show that, under application of an electric field greater than a triggering electric field Ec approximately 0.6 kV/mm, laponite aggregates assemble into chain- and/or columnlike structures in the oil. Without an applied electric field, the steady-state shear behavior of such suspensions is Newtonian-like. Under application of an electric field larger than Ec, it changes dramatically as a result of the changes in the microstructure: a significant yield stress is measured, and under continuous shear the fluid is shear-thinning. The rheological properties, in particular the dynamic and static shear stress, were studied as a function of particle volume fraction for various strengths (including null) of the applied electric field. The flow curves at constant shear rate can be scaled with respect to both the particle fraction and electric field strength onto a master curve. This scaling is consistent with simple scaling arguments. The shape of the master curve accounts for the system's complexity; it approaches a standard power-law model at high Mason numbers. Both dynamic and static yield stresses are observed to depend on the particle fraction Phi and electric field E as PhibetaEalpha, with alpha approximately 1.85 and beta approximately 1 and 1.70 for the dynamic and static yield stresses, respectively. The yield stress was also determined as the critical stress at which there occurs a bifurcation in the rheological behavior of suspensions that are submitted to a constant shear stress; a scaling law with alpha approximately 1.84 and beta approximately 1.70 was obtained. The effectiveness of the latter technique confirms that such electrorheological (ER) fluids can be studied in the framework of thixotropic fluids. The method is very reproducible; we suggest that it could be used routinely for studying ER fluids. The measured overall yield stress behavior of the suspensions may be explained in terms of standard conduction models for electrorheological systems. Interesting prospects include using such systems for guided self-assembly of clay nanoparticles.

Conductivity versus Dielectric Mechanisms for Electrorheology

NASA Astrophysics Data System (ADS)

Davis, L. C.

1997-03-01

Electrorheological (ER) fluids are continuously and rapidly controllable by an electric field. Controllability of these materials permits the construction of novel intelligent systems such as semiactively controlled shock absorbers and vibration dampers, tunable composite beams and panels, and even reconfigurable Braille arrays. The eventual success of these applications depends in part on developing improved ER fluids, which requires a fundamental understanding of the physics and chemistry of these materials. ER fluids generally consist of highly polarizable colloidal particles suspended in an insulating oil. Particles are typically 1-10 microns in diameter and can be of a wide variety of materials including zeolites, barium titanate, conducting polymers, and oxide-coated metals. Electric fields of magnitude 1-5 kV/mm induce particle chaining and concomitant shear stresses of order 1 kPa. Recent experiments (J. M. Ginder and S. L. Ceccio, J. Rheol. 39, 211 (1995)) using square-wave electric-field excitation have helped to elucidate the mechanisms of ER activity. Immediately after a step-function increase of electric field, chaining occurs due to particle-particle forces arising from dielectric polarization (dipoles and higher multipoles), i.e., it is controlled by the dielectric mismatch between particles and fluid. On a longer time scale, currents flow in the fluid and in the particles so that the forces are eventually dominated by the conductivity mismatch. Characteristic times for the transition between the two regimes are 10-50 ms. Likewise, in the frequency domain, conductivity mismatch dominates the dc response of ER fluids whereas dielectric effects dominate for high frequencies. A theory of ER fluids is given including a model for non-linear effects at high electric fields.

Investigation of electrorheological properties of biodegradable modified cellulose/corn oil suspensions.

PubMed

Tilki, Tahir; Yavuz, Mustafa; Karabacak, Ciğdem; Cabuk, Mehmet; Ulutürk, Mehmet

2010-03-30

Considerable scientific and industrial interest is currently being focused on a class of materials known as electrorheological (ER) fluids, which display remarkable rheological behaviour, being able to convert rapidly and repeatedly from a liquid to solid when an electric field (E) is applied or removed. In this study, biodegradable cellulose was modified and converted to their carboxyl salts. Modified cellulose is characterised by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA) and conductivity measurements. Suspensions of cellulose (C) and modified cellulose (MC) were prepared in insulated corn oil (CO). The effects of electric field strength, shear rate, shear stress, temperature, etc. of these suspensions onto ER activity were determined. Rheological measurements were carried out via a rotational rheometer with a high-voltage generator to investigate the effects of electric field strength and particle concentration on ER performance. The results show that the ER properties are enhanced by increasing the particle concentration and electric field strength. Also the cellulose-based ER fluids exhibit viscoelastic behaviour under an applied electric field due to the chain formation induced by electric polarization between particles. Copyright 2009 Elsevier Ltd. All rights reserved.

A haptic sensor-actor-system based on ultrasound elastography and electrorheological fluids for virtual reality applications in medicine.

PubMed

Khaled, W; Ermert, H; Bruhns, O; Boese, H; Baumann, M; Monkman, G J; Egersdoerfer, S; Meier, A; Klein, D; Freimuth, H

2003-01-01

Mechanical properties of biological tissue represent important diagnostic information and are of histological relevance (hard lesions, "nodes" in organs: tumors; calcifications in vessels: arteriosclerosis). The problem is, that such information is usually obtained by digital palpation only, which is limited with respect to sensitivity. It requires intuitive assessment and does not allow quantitative documentation. A suitable sensor is required for quantitative detection of mechanical tissue properties. On the other hand, there is also some need for a realistic mechanical display of those tissue properties. Suitable actuator arrays with high spatial resolution and real-time capabilities are required operating in a haptic sensor actuator system with different applications. The sensor system uses real time ultrasonic elastography whereas the tactile actuator is based on electrorheological fluids. Due to their small size the actuator array elements have to be manufactured by micro-mechanical production methods. In order to supply the actuator elements with individual high voltages a sophisticated switching and control concept have been designed. This haptic system has the potential of inducing real time substantial forces, using a compact lightweight mechanism which can be applied to numerous areas including intraoperative navigation, telemedicine, teaching, space and telecommunication.

Simulation study on the trembling shear behavior of eletrorheological fluid.

PubMed

Yang, F; Gong, X L; Xuan, S H; Jiang, W Q; Jiang, C X; Zhang, Z

2011-07-01

The trembling shear behavior of electrorheological (ER) fluids has been investigated by using a computer simulation method, and a shear-slide boundary model is proposed to understand this phenomenon. A thiourea-doped Ba-Ti-O ER fluid which shows a trembling shear behavior was first prepared and then systematically studied by both theoretical and experimental methods. The shear curves of ER fluids in the dynamic state were simulated with shear rates from 0.1 to 1000 s(-1) under different electric fields. The simulation results of the flow curves match the experimental results very well. The trembling shear curves are divided into four regions and each region can be explained by the proposed model.

Cellulose-Based Smart Fluids under Applied Electric Fields

PubMed Central

Choi, Kisuk; Gao, Chun Yan; Nam, Jae Do

2017-01-01

Cellulose particles, their derivatives and composites have special environmentally benign features and are abundant in nature with their various applications. This review paper introduces the essential properties of several types of cellulose and their derivatives obtained from various source materials, and their use in electro-responsive electrorheological (ER) suspensions, which are smart fluid systems that are actively responsive under applied electric fields, while, at zero electric field, ER fluids retain a liquid-like state. Given the actively controllable characteristics of cellulose-based smart ER fluids under an applied electric field regarding their rheological and dielectric properties, they can potentially be applied for various industrial devices including dampers and haptic devices. PMID:28891966

Electrorheological Fluid Based Force Feedback Device

NASA Technical Reports Server (NTRS)

Pfeiffer, Charles; Bar-Cohen, Yoseph; Mavroidis, Constantinos; Dolgin, Benjamin

1999-01-01

Parallel to the efforts to develop fully autonomous robots, it is increasingly being realized that there are applications where it is essential to have a fully controlled robot and "feel" its operating conditions, i.e. telepresence. This trend is a result of the increasing efforts to address tasks where humans can perform significantly better but, due to associated hazards, distance, physical limitations and other causes, only robots can be employed to perform these tasks. Such robots need to be assisted by a human that remotely controls the operation. To address the goal of operating robots as human surrogates, the authors launched a study of mechanisms that provide mechanical feedback. For this purpose, electrorheological fluids (ERF) are being investigated for the potential application as miniature haptic devices. This family of electroactive fluids has the property of changing the viscosity during electrical stimulation. Consequently, ERF can be used to produce force feedback haptic devices for tele-operated control of medical and space robotic systems. Forces applied at the robot end-effector due to a compliant environment are reflected to the user using an ERF device where a change in the system viscosity will occur proportionally to the transmitted force. Analytical model and control algorithms are being developed taking into account the non-linearities of these type of devices. This paper will describe the concept and the developed mechanism of ERF based force feedback. The test process and the physical properties of this device will be described and the results of preliminary tests will be presented.

Synthesis and electrorheological characteristics of polyaniline/organoclay nanoparticles via Pickering emulsion polymerization

NASA Astrophysics Data System (ADS)

Fang, F. F.; Liu, Y. D.; Choi, H. J.

2010-12-01

Conducting polymer/inorganic composite particles have been regarded as a potential candidate material for electrorheological (ER) fluids when dispersed in non-conducting oils due to their synergistic physical properties such as enhanced thermal stability and high dielectric properties. In this study, we fabricated polyaniline (PANI)/clay nanoparticles with unique core-shell structure via Pickering emulsion in the phase of toluene by adopting exfoliated clay as a stabilizer. Successfully synthesized PANI nanospheres which were initialized by oil-soluble benzoyl peroxide possess a polydispersed size distribution of particles ranging from 200 nm to 1 µm. Surface morphology was revealed by SEM images in which some clay sheets were found to wrap the PANI nanoparticles compactly. TEM images explicitly confirm the position of exfoliated clay layers around the nanospheres. In addition, some nano-scaled particles showed an irregular shape because clay plates are difficult to bend while wrapping the very tiny PANI nanoparticles, so the x-ray diffraction (XRD) pattern did not indicate any obvious sharp peak, demonstrating the nearly completely exfoliated clay layers. Besides these, thermal gravimetric analysis (TGA) data also gave additional information on thermal stability and composition. Finally, the ER fluid was prepared by dispersing PANI/clay nanoparticles in silicone oil and the ER performance was investigated via a rotational rheometer under an applied electric field.

Influence of liquid phase on nanoparticle-based giant electrorheological fluid.

PubMed

Gong, Xiuqing; Wu, Jinbo; Huang, Xianxiang; Wen, Weijia; Sheng, Ping

2008-04-23

We show that the chemical structures of silicone oils can have an important role in the giant electrorheological (GER) effect. The interaction between silicone oils and solid nanoparticles is found to significantly influence the ER effect. By increasing the kinematic viscosity of silicone oils, which is a function of siloxane chain length, sol-like, gel-like and clay-like appearances of the constituted ER fluids were observed. Different functional-group-terminated silicone oils were also employed as the dispersing media. Significant differences of yield stress were found. We systematically study the effect of siloxane chain lengths on the permeability of oils traveling through the porous spaces between the particles (using the Washburn method), oils adsorbed on the particles' surface (using FT-IR spectra), as well as their particle size distribution (using dynamic light scattering). Our results indicate the hydrogen bonds are instrumental in linking the silicone oil to GER solid particles, and long chain lengths can enhance the agglomeration of the GER nanoparticles to form large clusters. An optimal oil structure, with hydroxyl-terminated silicone oil and a suitable viscosity, was chosen which can create the highest yield stress of ∼300 kPa under a 5 kV mm(-1) DC electric field.

PREFACE: 13th International Conference on Electrorheological Fluids and Magnetorheological Suspensions (ERMR2012)

NASA Astrophysics Data System (ADS)

Unal, Halil Ibrahim

2013-02-01

Conference photograph The 13th International Conference on Electrorheological Fluids and Magnetorheological Suspensions (ERMR2012) was held in Ankara, Turkey at Gazi University in the Architect Kemaleddin historical hall on 2-6 July 2012. The first International Conference on Electrorheological Fluids and Magnetorheological Suspensions took place nearly 25 years ago and this conference continued the same tradition by providing an arena for researchers around the world to present their new research findings in these fields, and gave them the opportunity to learn about the latest research and technology and to renew their acquaintances. The meeting brought together scientists and engineers in multidisciplinary areas such as chemical engineering, mechanical engineering, materials science and engineering, physics, chemistry and polymer science and technology, to explore the state-of-art technology, identify key areas to be focused on and discuss their problems/issues. All oral presentations were held in a single session to enhance the interactions between the scientists and engineers. The ERMR2012 Conference included plenary lectures given by prominent leaders in their respective fields. About 130 participants from more than 50 organizations attended the conference and 15 plenary speeches, 64 oral presentations and 57 poster presentations took place in the following areas: (i) synthesis, characterization and processing of novel ER/MR materials, (ii) dynamics, chain and structure formation of ER/MR materials, (iii) ER/MR elastomers, ferrogels and their characterizations, (iv) rheological techniques and measurements of ER/MR materials, (v) modeling and simulations of ER/MR materials, (vi) device development and control techniques and (vii) applications of ER/MR materials. The ERMR2012 International Conference began with Turkish classical music performed by the musicians of the Ministry of Culture and Tourism. Rector Professor Dr R Ayhan welcomed the participants and the conference chair Professor H I Unal delivered an opening talk before the plenary lectures. Magnetorheological (MR) materials and their applications featured prominently at the ERMR2012 Conference. C A Evrensel from the University of Nevada, USA, opened the first session with a plenary speech on 'Magnetorheological Fluids for Cancer Therapy'. In the field of magnetorheological elastomers (MRE), S Odenbach from TU Dresden, Germany highlighted new developments in data management which enable single particle analysis and statistical analysis of the structures in an MRE in his plenary lecture. Another plenary lecture in the MRE field was given by F Gordaninejad (University of Nevada, USA) on new developments for integrated systems with thick MREs. D Barber (LORD Corporation, USA) gave details of the latest developments of LORD® MR fluids at extremes in his plenary speech. R Hidalgo Alvarez from the University of Granada, Spain, focused on particle shape effects in MR fluids in his plenary talk. D J Klingenberg (University of Wisconsin, USA) illustrated how the increased extent of layer formation increases the yield stress by increasing the stresses transmitted by both the magnetizable and nonmagnetizable spheres in his plenary lecture. S Smoukov from Cambridge University, UK, demonstrated magnetically responsive bi-stable hierarchical materials with novel functionality, which can be effectively used to design sustainable and energy-responsive systems. J de Vicente from the University of Granada, Spain, highlighted true yield stress in magnetorheology with the aid of simulations and experimental techniques for a wide range of MR fluids, inverse ferrofluids and ionic liquids-based MR fluids in his plenary speech. H Böse (Fraunhofer Institute, Germany) gave his plenary speech on magnetorheological torque transmission devices with permanent magnets. W Li (University of Wollongong, Australia), M Nakano (Tohoku University, Japan) and S Xuan (University of Science and Technology of China) gave plenary talks on novel MR shear thickening fluids, MR rubber composites and MR plastomers, respectively. H J Choi (INHA University, Korea), X Zhao (Northwestern Polytechnical University, China) and R Tao (Temple University, USA) delivered plenary lectures on issues relating to the area of electrorheological (ER) fluids. In their talks, Choi and Zhao covered novel ER materials with core-shell structured microspheres and micro/nano hierarchical structured titania particles, respectively, and Tao focused on the reduction of the viscosity of liquid suspensions for energy applications in transporting crude oil via pipelines. Attendance of the presentations was exceptionally high. Poster presentations were divided into two sessions and held in the afternoons after the close of the sessions, which were filled with stimulating discussions. The award for the best student research in the area of electrorheological fluids, sponsored by the Winslow family, was given to Y D Liu of INHA University, Korea on research entitled 'Copolyaniline coated monodisperse polystyrene microparticles and their electrorheological response'. The award for the best student research on magnetorheological suspensions, sponsored by the LORD Corporation, was given to S Kaneko of Keio University, Japan on research entitled 'Effect of a magnetic field on sloshing pressure in a magnetic fluid'. Besides the purely scientific program during the five days, some special events were also organized. A guided tour of the old city and some important landmarks of the capital city of Ankara were organized before the Gala Dinner. Special samples of Turkish classical music and folk dancing were performed by a group from the Republic of Turkey Ministry of Culture and Tourism to exhibit Turkish culture to the delegates at Gala Night, which was truly appreciated. Following the conclusion of this successful meeting, the next conference is expected to be organized at the University of Granada, Spain by Professor F Gonzalez-Caballero in 2014. It is expected that during the next conference, the interaction between polymer chemists synthesizing the new ER/MR materials, experimentalists from the rheological side characterizing their rheological properties, theoretical physicists describing the electric field and magnetic field dependent phenomena in ER/MR fluids rheology, and mechanical engineers conducting vibration damping tests will give rise to a deeper understanding of the ER/MR phenomena and will result in new findings in this field. The conference was sponsored by Gazi University, Anton-Paar GmbH, Kurimoto Ltd., Anamed Analitik Grup, TA Instruments, LORD Corporation, Turkish Powder Metallurgy Association (TTMD), LiKrom Ltd, Atomika Ltd., Turkish Patent Institute (TPI), Berkecan Ltd., Kurukahveci Mehmed Efendi Mahdumlari and Turkish Science-Research Foundation (TUBAV). The organizing committee truly appreciates the support from these organizations. Special appreciation is also due to my students O Erol and H C Gullu. I would also like to thank members of the Local Organizing Committee and International Advisory Board. Guest Editor H Ibrahim Unal Gazi University Science Faculty Chemistry Department 06500 Ankara/Turkey E-mail: hiunal@gazi.edu.tr

Proceedings of the International Conference on Electrorheological Fluids (4th) Held in Feldkirch (Austria) on 20-23 July 1993

DTIC Science & Technology

1994-01-01

which predicts that cylinder diameter or spacing has any influence on the dielctric spectra once the concer~tration of cylinders is fixed, and thus...differences in column girth and spacing . Furthermore, in applying the Sillars’ model to the present situation no precise meaning is attached to his end...cm). The test cell comprises two duralumin electrodes 9 cm in diameter spaced by 1.4 cm. Thu planar section of the upper half sphere, solid with a

Student designed experiments to learn fluids

NASA Astrophysics Data System (ADS)

Stern, Catalina

2013-11-01

Lasers and high speed cameras are a wonderful tool to visualize the very complex behavior of fluids, and to help students grasp concepts like turbulence, surface tension and vorticity. In this work we present experiments done by physics students in their senior year at the School of Science of the National University of Mexico as a final project in the continuum mechanics course. Every semester, the students make an oral presentation of their work and videos and images are kept in the web page ``Pasión por los Fluidos''. I acknowledge support from the Physics Department of Facultad de Ciencias, Universidad Nacional Autónoma de México.

Synthesis of flower-like BaTiO3/Fe3O4 hierarchically structured particles and their electrorheological and magnetic properties.

PubMed

Wang, Baoxiang; Yin, Yichao; Liu, Chenjie; Yu, Shoushan; Chen, Kezheng

2013-07-21

Flower-like BaTiO3/Fe3O4 hierarchically structured particles composed of nano-scale structures on micro-scale materials were synthesized by a simple solvothermal approach and characterized by the means of X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), magnetic testing and rotary viscometer. The influences on the morphology and structure of solvothermal times, type and amount of surfactant, EG : H2O ratio, etc. were studied. Magnetic testing results show that the samples have strong magnetism and they exhibit superparamagnetic behavior, as evidenced by no coercivity and the remanence at room temperature, due to their very small sizes, observed on the M-H loop. The saturation magnetization (M(s)) value can achieve 18.3 emu g(-1). The electrorheological (ER) effect was investigated using a suspension of the flower-like BaTiO3/Fe3O4 hierarchically structured particles dispersed in silicone oil. We can observe a slight shear-thinning behavior of shear viscosity at a low shear rate region even at zero applied electric field and a Newtonian fluid behavior at high shear rate regions.

Novel electrorheological properties of a metal-organic framework Cu3(BTC)2.

PubMed

Liu, Ying Dan; Kim, Jun; Ahn, Wha-Seung; Choi, Hyoung Jin

2012-06-07

A metal-organic framework, Cu(3)(BTC)(2), was synthesized and applied as an electro-responsive electrorheological material dispersed in insulating oil. Powder of crystalline Cu(3)(BTC)(2) exhibited excellent chain-like structures and controllable rheological properties in an applied electric field.

Ultraviolet light-responsive photorheological fluids: as a new class of smart fluids

NASA Astrophysics Data System (ADS)

Cho, Min-Young; Kim, Ji-Sik; Choi, Hyoung Jin; Choi, Seung-Bok; Kim, Gi-Woo

2017-05-01

We present a comprehensive introduction to the photorheological (PR) fluids whose rheological behavior can be changed by ultraviolet (UV) light with a wavelength of 365 nm. When the PR fluid was exposed to UV light, the viscosity of the fluid decreased, while the viscosity recovered to its initial value when UV light was turned off, indicating that the viscosity of these types of fluids can be reversible and tunable by UV light. Contrary to conventional smart fluids, such as electrorheological and magnetorheological fluids, PR fluid does not suffer from a phase splitting problem because it exists in a single-phase solution. Additionally, the PR fluid does not require any contact component, such as electrodes, and electric wires that are essential components for conventional smart fluids. In this work, the PR fluids were synthesized by doping lecithin/sodium deoxycholate reverse micelles with a photo-chromic spiropyran compound. It is demonstrated that the viscosity changes of PR fluids can be induced by UV light, and their rheological properties are examined in detail. In addition, an example of tailoring rheological properties using photoluminescence was introduced for improved response time. One of the potential applications, such as microfluidic flow control using the PR fluids, is also briefly presented.

Quasi-steady Bingham plastic analysis of an electrorheological flow mode bypass damper with piston bleed

NASA Astrophysics Data System (ADS)

Lindler, Jason; Wereley, Norman M.

2003-06-01

We present an improved experimental validation of our nonlinear quasi-steady electrorheological (ER) and magnetorheological damper analysis, using an idealized Bingham plastic shear flow mechanism, for the flow mode of damper operation with leakage effect. To validate the model, a double-acting ER valve or bypass damper was designed and fabricated. Both the hydraulic cylinder and the bypass duct have cylindrical geometry, and damping forces are developed in the annular bypass via Poiseuille flow. The ER fluid damper contains a controlled amount of leakage around the piston head. The leakage allows ER fluid to flow from one side of the piston head to the opposite side without passing through the ER bypass. For this flow mode damper, the damping coefficient, defined as the ratio of equivalent viscous damping of the Bingham plastic material, Ceq, to the Newtonian viscous damping, C, is a function of the non-dimensional plug thickness only. The damper was tested for varying conditions of applied electric field and frequency using a mechanical damper dynamometer. In this analysis, the leakage damping coefficient with incorporated leakage effects, predict the amount of energy dissipated for a complete cycle of the piston rod. Measured force verses displacement cycles for multiple frequencies and electric fields validate the ability of the non-dimensional groups and the leakage damping coefficient to predict the damping levels for an ER bypass damper with leakage. Based on the experimental validation of the model using these data, the Bingham plastic analysis is shown to be an effective tool for the analysis-based design of double-acting ER bypass dampers.

Smart Fluid System Dually Responsive to Light and Electric Fields: An Electrophotorheological Fluid.

PubMed

Yoon, Chang-Min; Jang, Yoonsun; Noh, Jungchul; Kim, Jungwon; Jang, Jyongsik

2017-10-24

Electrophotorheological (EPR) fluids, whose rheological activity is dually responsive to light and electric fields (E fields), is formulated by mixing photosensitive spiropyran-decorated silica (SP-sSiO 2 ) nanoparticles with zwitterionic lecithin and mineral oil. A reversible photorheological (PR) activity of the EPR fluid is developed via the binding and releasing mechanism of lecithin and merocyanine (MC, a photoisomerized form of SP) under ultraviolet (UV) and visible (VIS) light applications. Moreover, the EPR fluid exhibits an 8-fold higher electrorheological (ER) performance compared to the SP-sSiO 2 nanoparticle-based ER fluid (without lecithin) under an E field, which is attributed to the enhanced dielectric properties facilitated by the binding of the lecithin and SP molecules. Upon dual application of UV light and an E field, the EPR fluid exhibits high EPR performance (ca. 115.3 Pa) that far exceeds its separate PR (ca. 0.8 Pa) and ER (ca. 57.5 Pa) activities, because of the synergistic contributions of the PR and ER effects through rigid and fully connected fibril-like structures. Consequently, this study offers a strategy on formulation of dual-stimuli responsive smart fluid systems.

Shear mode ER transfer function for robotic applications

NASA Astrophysics Data System (ADS)

Tan, K. P.; Stanway, R.; Bullough, W. A.

2005-06-01

Electro-rheological (ER) fluids are becoming popular in modern industrial applications. The advantage of employing ER devices is due to the ease of energizing the ER fluids at fast speeds of response. One innovation in ER applications could be in the positioning control of the robotic arm using an ER clutch. In order to actuate the manipulator, the ER output torque response is required. However, the behaviour of this ER torque response at different input conditions is not clearly understood. Therefore, in this paper, a sample study of the ER output torque is conducted. The ER output torque responses at different input parameters are studied carefully for the establishment of an appropriate ER transfer function in shear mode. This transfer function will serve as an important feature in future ER-actuated robot arm's control process.

ER fluid applications to vibration control devices and an adaptive neural-net controller

NASA Astrophysics Data System (ADS)

Morishita, Shin; Ura, Tamaki

1993-07-01

Four applications of electrorheological (ER) fluid to vibration control actuators and an adaptive neural-net control system suitable for the controller of ER actuators are described: a shock absorber system for automobiles, a squeeze film damper bearing for rotational machines, a dynamic damper for multidegree-of-freedom structures, and a vibration isolator. An adaptive neural-net control system composed of a forward model network for structural identification and a controller network is introduced for the control system of these ER actuators. As an example study of intelligent vibration control systems, an experiment was performed in which the ER dynamic damper was attached to a beam structure and controlled by the present neural-net controller so that the vibration in several modes of the beam was reduced with a single dynamic damper.

Operational durability of a giant ER valve for Braille display

NASA Astrophysics Data System (ADS)

Luning, Xu; Han, Li; Yufei, Li; Shen, Rong; Kunquan, Lu

2017-05-01

The compact configuration of giant ER (electrorheological) valves provides the possibility of realizing a full-page Braille display. The operational durability of ER valves is a key issue in fulfilling a Braille display. A giant ER valve was used to investigate the variations in pressure drops and critical pressure drops of the valves over a long period under some typical operational parameters. The results indicate that neither the pressure drops nor critical pressure drops of giant ER valves show apparent deterioration over a long period. Without ER fluid exchange, a blockage appears in the channel of the valve because the ER structures induced by an external electric field cannot be broken by the Brownian motion of hydraulic oil molecules when the external electric field is removed. Forcing ER fluid flow is an effective and necessary method to keep the channel of the valve unblocked. Thus the operational durability of the valve using giant ER fluids is able to meet the demands of Braille display.

a New ER Fluid Based Haptic Actuator System for Virtual Reality

NASA Astrophysics Data System (ADS)

Böse, H.; Baumann, M.; Monkman, G. J.; Egersdörfer, S.; Tunayar, A.; Freimuth, H.; Ermert, H.; Khaled, W.

The concept and some steps in the development of a new actuator system which enables the haptic perception of mechanically inhomogeneous virtual objects are introduced. The system consists of a two-dimensional planar array of actuator elements containing an electrorheological (ER) fluid. When a user presses his fingers onto the surface of the actuator array, he perceives locally variable resistance forces generated by vertical pistons which slide in the ER fluid through the gaps between electrode pairs. The voltage in each actuator element can be individually controlled by a novel sophisticated switching technology based on optoelectric gallium arsenide elements. The haptic information which is represented at the actuator array can be transferred from a corresponding sensor system based on ultrasonic elastography. The combined sensor-actuator system may serve as a technology platform for various applications in virtual reality, like telemedicine where the information on the consistency of tissue of a real patient is detected by the sensor part and recorded by the actuator part at a remote location.

Synthesis of kenaf cellulose carbamate and its smart electric stimuli-response.

PubMed

Gan, Sinyee; Piao, Shang Hao; Choi, Hyoung Jin; Zakaria, Sarani; Chia, Chin Hua

2016-02-10

Cellulose carbamate (CC) was produced from kenaf core pulp (KCP) via a microwave reactor-assisted method. The formation of CC was confirmed by Fourier transform infrared spectroscopy and nitrogen content analysis. The degree of substitution, zeta potential and size distribution of CC were also determined. The CC was characterized with scanning electron microscopy, X-ray diffraction and thermogravimetry analysis. The CC particles were then dispersed in silicone oil to prepare CC-based anhydrous electric stimuli-responsive electrorheological (ER) fluids. Rhelogical measurement was carried out using rotational rheometer with a high voltage generator in both steady and oscillatory shear modes to examine the effect of electric field strength on the ER characteristics. The results showed that the increase in electric field strength has enhanced the ER properties of CC-based ER fluid due to the chain formation induced by electric polarization among the particles. Copyright © 2015 Elsevier Ltd. All rights reserved.

On necessary conditions for the comparison principle and the sub- and supersolution method for the stationary Kirchhoff equation

NASA Astrophysics Data System (ADS)

Iturriaga, Leonelo; Massa, Eugenio

2018-01-01

In this paper, we propose a counterexample to the validity of the comparison principle and of the sub- and supersolution method for nonlocal problems like the stationary Kirchhoff equation. This counterexample shows that in general smooth bounded domains in any dimension, these properties cannot hold true if the nonlinear nonlocal term M (∥u∥ 2 ) is somewhere increasing with respect to the H01-norm of the solution. Comparing with the existing results, this fills a gap between known conditions on M that guarantee or prevent these properties and leads to a condition that is necessary and sufficient for the validity of the comparison principle. It is worth noting that equations similar to the one considered here have gained interest recently for appearing in models of thermo-convective flows of non-Newtonian fluids or of electrorheological fluids, among others.

Control of repulsive force in a virtual environment using an electrorheological haptic master for a surgical robot application

NASA Astrophysics Data System (ADS)

Oh, Jong-Seok; Choi, Seung-Hyun; Choi, Seung-Bok

2014-01-01

This paper presents control performances of a new type of four-degrees-of-freedom (4-DOF) haptic master that can be used for robot-assisted minimally invasive surgery (RMIS). By adopting a controllable electrorheological (ER) fluid, the function of the proposed master is realized as a haptic feedback as well as remote manipulation. In order to verify the efficacy of the proposed master and method, an experiment is conducted with deformable objects featuring human organs. Since the use of real human organs is difficult for control due to high cost and moral hazard, an excellent alternative method, the virtual reality environment, is used for control in this work. In order to embody a human organ in the virtual space, the experiment adopts a volumetric deformable object represented by a shape-retaining chain linked (S-chain) model which has salient properties such as fast and realistic deformation of elastic objects. In haptic architecture for RMIS, the desired torque/force and desired position originating from the object of the virtual slave and operator of the haptic master are transferred to each other. In order to achieve the desired torque/force trajectories, a sliding mode controller (SMC) which is known to be robust to uncertainties is designed and empirically implemented. Tracking control performances for various torque/force trajectories from the virtual slave are evaluated and presented in the time domain.

Design and integration of an all-in-one biomicrofluidic chip

PubMed Central

Liu, Liyu; Cao, Wenbin; Wu, Jingbo; Wen, Weijia; Chang, Donald Choy; Sheng, Ping

2008-01-01

We demonstrate a highly integrated microfluidic chip with the function of DNA amplification. The integrated chip combines giant electrorheological-fluid actuated micromixer and micropump with a microheater array, all formed using soft lithography. Internal functional components are based on polydimethylsiloxane (PDMS) and silver∕carbon black-PDMS composites. The system has the advantages of small size with a high degree of integration, high polymerase chain reaction efficiency, digital control and simple fabrication at low cost. This integration approach shows promise for a broad range of applications in chemical synthesis and biological sensing∕analysis, as different components can be combined to target desired functionalities, with flexible designs of different microchips easily realizable through soft lithography. PMID:19693370

Electrohydrodynamic fibrillation governed enhanced thermal transport in dielectric colloids under a field stimulus.

PubMed

Dhar, Purbarun; Maganti, Lakshmi Sirisha; Harikrishnan, A R

2018-05-30

Electrorheological (ER) fluids are known to exhibit enhanced viscous effects under an electric field stimulus. The present article reports the hitherto unreported phenomenon of greatly enhanced thermal conductivity in such electro-active colloidal dispersions in the presence of an externally applied electric field. Typical ER fluids are synthesized employing dielectric fluids and nanoparticles and experiments are performed employing an in-house designed setup. Greatly augmented thermal conductivity under a field's influence was observed. Enhanced thermal conduction along the fibril structures under the field effect is theorized as the crux of the mechanism. The formation of fibril structures has also been experimentally verified employing microscopy. Based on classical models for ER fluids, a mathematical formalism has been developed to predict the propensity of chain formation and statistically feasible chain dynamics at given Mason numbers. Further, a thermal resistance network model is employed to computationally predict the enhanced thermal conduction across the fibrillary colloid microstructure. Good agreement between the mathematical model and the experimental observations is achieved. The domineering role of thermal conductivity over relative permittivity has been shown by proposing a modified Hashin-Shtrikman (HS) formalism. The findings have implications towards better physical understanding and design of ER fluids from both 'smart' viscoelastic as well as thermally active materials points of view.

Virtual reality robotic telesurgery simulations using MEMICA haptic system

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Mavroidis, Constantinos; Bouzit, Mourad; Dolgin, Benjamin; Harm, Deborah L.; Kopchok, George E.; White, Rodney

2001-01-01

The authors conceived a haptic mechanism called MEMICA (Remote Mechanical Mirroring using Controlled stiffness and Actuators) that can enable the design of high dexterity, rapid response, and large workspace haptic system. The development of a novel MEMICA gloves and virtual reality models are being explored to allow simulation of telesurgery and other applications. The MEMICA gloves are being designed to provide intuitive mirroring of the conditions at a virtual site where a robot simulates the presence of a human operator. The key components of MEMICA are miniature electrically controlled stiffness (ECS) elements and electrically controlled force and stiffness (ECFS) actuators that are based on the use of Electro-Rheological Fluids (ERF. In this paper the design of the MEMICA system and initial experimental results are presented.

Method and apparatus for suppressing regenerative instability and related chatter in machine tools

DOEpatents

Segalman, Daniel J.; Redmond, James M.

2001-01-01

Methods of and apparatuses for mitigating chatter vibrations in machine tools or components thereof. Chatter therein is suppressed by periodically or continuously varying the stiffness of the cutting tool (or some component of the cutting tool), and hence the resonant frequency of the cutting tool (or some component thereof). The varying of resonant frequency of the cutting tool can be accomplished by modulating the stiffness of the cutting tool, the cutting tool holder, or any other component of the support for the cutting tool. By periodically altering the impedance of the cutting tool assembly, chatter is mitigated. In one embodiment, a cyclic electric (or magnetic) field is applied to the spindle quill which contains an electro-rheological (or magneto-rheological) fluid. The variable yield stress in the fluid affects the coupling of the spindle to the machine tool structure, changing the natural frequency of oscillation. Altering the modal characteristics in this fashion disrupts the modulation of current tool vibrations with previous tool vibrations recorded on the workpiece surface.

Method and apparatus for suppressing regenerative instability and related chatter in machine tools

DOEpatents

Segalman, Daniel J.; Redmond, James M.

1999-01-01

Methods of and apparatuses for mitigating chatter vibrations in machine tools or components thereof. Chatter therein is suppressed by periodically or continuously varying the stiffness of the cutting tool (or some component of the cutting tool), and hence the resonant frequency of the cutting tool (or some component thereof). The varying of resonant frequency of the cutting tool can be accomplished by modulating the stiffness of the cutting tool, the cutting tool holder, or any other component of the support for the cutting tool. By periodically altering the impedance of the cutting tool assembly, chatter is mitigated. In one embodiment, a cyclic electric (or magnetic) field is applied to the spindle quill which contains an electro-rheological (or magneto-rheological) fluid. The variable yield stress in the fluid affects the coupling of the spindle to the machine tool structure, changing the natural frequency of oscillation. Altering the modal characteristics in this fashion disrupts the modulation of current tool vibrations with previous tool vibrations recorded on the workpiece surface.

Controllable Sonar Lenses and Prisms Based on ERFs

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Sherrit, Stewart; Chang, Zensheu; Bao, Xiaoqi; Paustian, Iris; Lopes, Joseph; Folds, Donald

2004-01-01

Sonar-beam-steering devices of the proposed type would contain no moving parts and would be considerably smaller and less power-hungry, relative to conventional multiple-beam sonar arrays. The proposed devices are under consideration for installation on future small autonomous underwater vehicles because the sizes and power demands of conventional multiple-beam arrays are excessive, and motors used in single-beam mechanically scanned systems are also not reliable. The proposed devices would include a variety of electrically controllable acoustic prisms, lenses, and prism/lens combinations both simple and compound. These devices would contain electrorheological fluids (ERFs) between electrodes. An ERF typically consists of dielectric particles floating in a dielectric fluid. When an electric field is applied to the fluid, the particles become grouped into fibrils aligned in rows, with a consequent increase in the viscosity of the fluid and a corresponding increase in the speed of sound in the fluid. The change in the speed of sound increases with an increase in the applied electric field. By thus varying the speed of sound, one varies the acoustic index of refraction, analogously to varying the index of refraction of an optical lens or prism. In the proposed acoustic devices, this effect would be exploited to control the angles of refraction of acoustic beams, thereby steering the beams and, in the case of lenses, controlling focal lengths.

The electrorheological behavior of suspensions based on molten-salt synthesized lithium titanate nanoparticles and their core-shell titanate/urea analogues.

PubMed

Plachy, T; Mrlik, M; Kozakova, Z; Suly, P; Sedlacik, M; Pavlinek, V; Kuritka, I

2015-02-18

This paper concerns the preparation of novel electrorheological (ER) materials using microwave-assisted synthesis as well as utilizing a suitable shell-providing system with enhanced ER performance. Lithium titanate nanoparticles were successfully synthesized, and their composition was confirmed via X-ray diffraction. Rheological properties were investigated in the absence as well as in the presence of an external electric field. Dielectric properties clarified the response of the particles to the application of an electric field. The urea-coated lithium titanate nanoparticle-based suspension exhibits higher ER performance in comparison to suspensions based on bare particles.

Monitoring artificially stimulated fluid movement in the Cretaceous Dakota aquifer, western Kansas

NASA Astrophysics Data System (ADS)

Macfarlane, Allen; Förster, Andrea; Merriam, Daniel; Schrötter, Jörg; Healey, John

2002-10-01

Aquifer properties can be evaluated by monitoring artificially stimulated fluid movements between wells, if the fluid is heated. Changes in the temperature profile recorded in observation wells indicate the flow path of the heated fluid, which in effect acts as a tracer. A fluid-flow experiment in the Cretaceous Dakota Formation at the Hodgeman County site, west-central Kansas, demonstrated the advantage of using the distributed optical-fiber temperature sensing method for monitoring transient temperature conditions in this hydrological application. The fluid flow in the aquifer was increased by producing water from a pumping well and injecting heated water in an injection well 13 m (43 ft) distant from the pumping well. The time-temperature series data obtained and compared with results from previous pumping tests point to interwell heterogeneity of the aquifer and to a zone in the sandstone aquifer of high hydraulic conductivity. However, the experiment would have allowed further clarification of aquifer heterogeneity and thermal properties if at least one observation well had been present between the injection and production wells. Résumé. Les caractéristiques d'un aquifère peuvent être évaluées en effectuant un suivi des mouvements du fluide stimulés artificiellement entre des puits, si le fluide est chauffé. Les variations de profils de température enregistrés dans les puits d'observation donnent des informations sur les directions d'écoulement du fluide chauffé, qui en fait se comporte comme un traceur. Réalisée dans la formation crétacée de Dakota, sur le site du Comté de Hodgeman (centre-ouest du Kansas), une expérience a démontré l'intérêt d'utiliser la méthode de détection distribuée de température par fibres optiques pour suivre les variations de température dans cette application hydrologique. L'écoulement du fluide dans l'aquifère a été favorisé en extrayant de l'eau par pompage et en injectant de l'eau chaude dans un puits d'injection distant de 13 m du puits de pompage. La chronique de température obtenue et comparée aux résultats d'essais de pompage précédents fait apparaître l'hétérogénéité de l'aquifère entre les puits et l'existence d'une zone de forte conductivité hydraulique dans l'aquifère de grès. Toutefois, l'expérience aurait fourni des éclaircissements supplémentaires sur l'hétérogénéité de l'aquifère et sur ses propriétés thermiques si au moins un puits d'observation avait été placé entre le puits d'injection et le puits de pompage. Resumen. Se puede evaluar las propiedades de un acuífero mediante la observación del movimiento de un fluido, calentado artificialmente, entre pozos. Los cambios registrados en el perfil de temperatura de los pozos de observación indican la trayectoria del fluido calentado, el cual actúa como un trazador. Un experimento de este tipo que se realizó en la formación cretácica de Dakota, en el condado de Hodgeman (porción occidental del centro de Kansas, Estados Unidos de América), demostró la ventaja de utilizar el método del sensor de temperatura con fibra óptica distribuída para medir condiciones transitorias de temperatura en esta aplicación hidrológica. El flujo del fluido en el acuífero aumentó con el bombeo de un pozo y la inyección de agua caliente en otro sondeo, que distaba 13 m (43 pies) del primero. Las series de temperatura obtenidas y comparadas con resultados de ensayos de bombeo previos resaltan la heterogeneidad del acuífero entre ambos pozos, así como la existencia de una zona de elevada conductividad hidráulica en el acuífero de la arenisca. Sin embargo, el experimento habría proporcionado más información sobre la heterogeneidad de la formación y sus propiedades termales si se hubiera dispuesto al menos de un punto de observación entre los pozos de inyección y bombeo.

Physics of field-responsive fluids

NASA Astrophysics Data System (ADS)

Wan, Tsz Kai Jones

Electrorheological (ER) fluid is a new class of material, which possesses a variety of potential applications, such as shock absorbers and clutches. It is formed by microparticles that are dispersed in a host fluid. The particles will form chains rapidly when we apply an electric field to the ER fluid. However, due to the inadequacy of knowledge, the proposed applications have not been commercialized yet. The prediction of the strength of the ER effect is the main concern in the theoretical investigation of ER fluids. The ER effect is originated from the induced interaction between the polarized particles in an ER fluid. Existing theories assume that the particles are at rest. In a realistic situation, the fluid flow exerts force and torque on the particles, setting the particles in both translational and rotational motions under these actions. Recent experiments showed that the induced forces between the rotating particles are markedly different from the values predicted by existing theories. To overcome the discrepancy between theory and experiment, we formulate a model to take the particle motion into account, and derive the dependence of forces on the angular velocity of the rotating particles. We develop first-principles methods to investigate the dynamic ER effects in which the suspended particles can have translational or rotational motions. A model based on the relaxation of polarization charge on the particle surfaces is proposed and solved for various experimental conditions. The method can be extended to study the ER effects of coated particles, crystalline particles, and to the magnetorheological effects of paramagnetic particles. Moreover, the nonlinear ER effects under a strong applied field will be studied by the same approach. The results may help in the preparation of materials for the design of ER fluids.

Active and passive interaction mechanism of smart materials for health monitoring of engineering structures: a review

NASA Astrophysics Data System (ADS)

Annamdas, Venu Gopal Madhav; Annamdas, Kiran Kumar

2009-03-01

Smart materials when interact with engineering structures, should have the capability to sense, measure, process, and detect any change in the selected variables (stress, damage) at critical locations. These smart materials can be classified into active and passive depending on the type of the structure, variables to be monitored, and interaction mechanism due to surface bonding or embedment. Some of the prominent smart materials are piezoelectric materials, micro fiber composite, polymers, shape memory alloys, electrostrictive and magnetostrictive materials, electrorheological and magnetorheological fluids and fiber optics. In addition, host structures do have the properties to support or repel the usage of smart materials inside or on it. This paper presents some of the most widely used smart materials and their interaction mechanism for structural health monitoring of engineering structures.

Characterization and experimental validation of a squeeze film damper with MR fluid in a rotor-bearing system

NASA Astrophysics Data System (ADS)

Dominguez-Nuñez, L. A.; Silva-Navarro, G.

2014-04-01

The general study and applications of Magneto-Rhelogical (MR) dampers have been spread in the lasts years but only some studies have been focusing on the vibration control problems on rotor-bearings systems. Squeeze-Film Dampers (SFD) are now commonly used to passively control the vibration response on rotor-bearing systems because they can provide flexibility, damping and extend the so-called stability thresholds in rotating machinery. More recently, SFD are combined with MR or Electro-Rheological (ER) fluids to introduce a semiactive control mechanism to modify the rotordynamic coefficients and deal with the robust performance of the overall system response for higher operating speeds. There are, however, some theoretical and technological problems that complicate their extensive use, like the relationship between the centering spring flexibility and the rheological behavior of the smart fluid to produce the SFD forces. In this work it is considered a SFD with MR fluid and a set of circular section beams in a squirrel cage arrangement in combination with latex seals as centering springs. The mathematical model analysis includes the controllable viscoelastic properties associated to the MR fluid. The characterization of the SFD is made by the determination of some coefficients associated with a modified Choi-Lee-Park polynomial model. During the analysis is considered a rotor-bearing system modeled using finite element methods. The SFD with MR fluid is connected to an experimental platform to validate and experimentally evaluate the overall system. Finally, to improve the open-loop system performance, a methodology for the use of different control schemes is proposed.

Active structuring of colloidal armour on liquid drops

NASA Astrophysics Data System (ADS)

Dommersnes, Paul; Rozynek, Zbigniew; Mikkelsen, Alexander; Castberg, Rene; Kjerstad, Knut; Hersvik, Kjetil; Otto Fossum, Jon

2013-06-01

Adsorption and assembly of colloidal particles at the surface of liquid droplets are at the base of particle-stabilized emulsions and templating. Here we report that electrohydrodynamic and electro-rheological effects in leaky-dielectric liquid drops can be used to structure and dynamically control colloidal particle assemblies at drop surfaces, including electric-field-assisted convective assembly of jammed colloidal ‘ribbons’, electro-rheological colloidal chains confined to a two-dimensional surface and spinning colloidal domains on that surface. In addition, we demonstrate the size control of ‘pupil’-like openings in colloidal shells. We anticipate that electric field manipulation of colloids in leaky dielectrics can lead to new routes of colloidosome assembly and design for ‘smart armoured’ droplets.

Active structuring of colloidal armour on liquid drops.

PubMed

Dommersnes, Paul; Rozynek, Zbigniew; Mikkelsen, Alexander; Castberg, Rene; Kjerstad, Knut; Hersvik, Kjetil; Otto Fossum, Jon

2013-01-01

Adsorption and assembly of colloidal particles at the surface of liquid droplets are at the base of particle-stabilized emulsions and templating. Here we report that electrohydrodynamic and electro-rheological effects in leaky-dielectric liquid drops can be used to structure and dynamically control colloidal particle assemblies at drop surfaces, including electric-field-assisted convective assembly of jammed colloidal 'ribbons', electro-rheological colloidal chains confined to a two-dimensional surface and spinning colloidal domains on that surface. In addition, we demonstrate the size control of 'pupil'-like openings in colloidal shells. We anticipate that electric field manipulation of colloids in leaky dielectrics can lead to new routes of colloidosome assembly and design for 'smart armoured' droplets.

Active structuring of colloidal armour on liquid drops

PubMed Central

Dommersnes, Paul; Rozynek, Zbigniew; Mikkelsen, Alexander; Castberg, Rene; Kjerstad, Knut; Hersvik, Kjetil; Otto Fossum, Jon

2013-01-01

Adsorption and assembly of colloidal particles at the surface of liquid droplets are at the base of particle-stabilized emulsions and templating. Here we report that electrohydrodynamic and electro-rheological effects in leaky-dielectric liquid drops can be used to structure and dynamically control colloidal particle assemblies at drop surfaces, including electric-field-assisted convective assembly of jammed colloidal ‘ribbons’, electro-rheological colloidal chains confined to a two-dimensional surface and spinning colloidal domains on that surface. In addition, we demonstrate the size control of ‘pupil’-like openings in colloidal shells. We anticipate that electric field manipulation of colloids in leaky dielectrics can lead to new routes of colloidosome assembly and design for ‘smart armoured’ droplets. PMID:23811716

Influence of a surface film on the particles on the electrorheological response

NASA Astrophysics Data System (ADS)

Wu, C. W.; Conrad, H.

1997-01-01

A conduction model is developed for the dc electrorheological (ER) response of highly conducting particles (e.g., metal particles) suspended in a weakly conducting oil. The numerical analyses show that a surface film with some conductivity is desired, but not a completely insulating film as previously proposed. Increasing the film conductivity leads to an increase in the ER yield stress. However, too high a conductivity will give an unacceptable level of current density. The film should also have an intermediate thickness. A small thickness increases the possibility of electrical breakdown in the film; too large a thickness decreases the ER effect. Good agreement exists between the yield stress and the current density predicted by our model and those measured.

Control of an ER haptic master in a virtual slave environment for minimally invasive surgery applications

NASA Astrophysics Data System (ADS)

Han, Young-Min; Choi, Seung-Bok

2008-12-01

This paper presents the control performance of an electrorheological (ER) fluid-based haptic master device connected to a virtual slave environment that can be used for minimally invasive surgery (MIS). An already developed haptic joint featuring controllable ER fluid and a spherical joint mechanism is adopted for the master system. Medical forceps and an angular position measuring device are devised and integrated with the joint to establish the MIS master system. In order to embody a human organ in virtual space, a volumetric deformable object is used. The virtual object is then mathematically formulated by a shape-retaining chain-linked (S-chain) model. After evaluating the reflection force, computation time and compatibility with real-time control, the haptic architecture for MIS is established by incorporating the virtual slave with the master device so that the reflection force for the object of the virtual slave and the desired position for the master operator are transferred to each other. In order to achieve the desired force trajectories, a sliding mode controller is formulated and then experimentally realized. Tracking control performances for various force trajectories are evaluated and presented in the time domain.

A constitutive theory of reacting electrolyte mixtures

NASA Astrophysics Data System (ADS)

Costa Reis, Martina; Wang, Yongqi; Bono Maurizio Sacchi Bassi, Adalberto

2013-11-01

A constitutive theory of reacting electrolyte mixtures is formulated. The intermolecular interactions among the constituents of the mixture are accounted for through additional freedom degrees to each constituent of the mixture. Balance equations for polar reacting continuum mixtures are accordingly formulated and a proper set of constitutive equations is derived with basis in the Müller-Liu formulation of the second law of thermodynamics. Moreover, the non-equilibrium and equilibrium responses of the reacting mixture are investigated in detail by emphasizing the inner and reactive structures of the medium. From the balance laws and constitutive relations, the effects of molecular structure of constituents upon the fluid flow are studied. It is also demonstrated that the local thermodynamic equilibrium state can be reached without imposing that the set of independent constitutive variables is time independent, neither spatially homogeneous nor null. The resulting constitutive relations presented throughout this work are of relevance to many practical applications, such as swelling of clays, developing of bio and polymeric membranes, and use of electrorheological fluids in industrial processes. The first author acknowledges financial support from National Counsel of Technological and Scientific Development (CNPq) and German Academic Exchange Service (DAAD).

New multifunction materials with both electrorheological performance and luminescence property

NASA Astrophysics Data System (ADS)

Chen, Ming-Xing; Shang, Yan-Li; Jia, Yun-Ling; Dong, Xiang-Yu; Ren, Jing; Li, Jun-Ran

2017-02-01

Novel multifunctional materials, the composites AlOOH-NaYFTb5 and AlOOH-NaYFTb10, containing AlO(OH) and β-NaYF4:5%Tb3+, have been synthesized via a facile hydrothermal route and a simple grinding method. The boehmite [AlO(OH)], yttrium nitrate [Y(NO3)3·6H2O], terbium nitrate, [Tb(NO3)3·6H2O], sodium citrate (Na3C6H5O7·2H2O) and sodium fluoride (NaF) were used as starting materials. The composition, electrorheological (ER) performance, and luminescence property of the functional materials were studied. Our results show that the composites not only have good electrorheological (ER) performance, but also have good optics property. The relative shear stress τ r ( τ r = τ E/ τ 0, τ E and τ 0 are the shear stresses at the electric field strength E = 4 and 0 kV/mm, respectively) values of the suspension (25 wt.%) of AlOOHNaYFTb5 material in silicone oil are all larger than 50 in a shear rate ranging from 0.06 to 26 s-1, the τr value reaches 1333 at a shear rate of 0.06 s-1. The material with such high ER activity and favorable luminescence performance is advantageous in its application as a multifunctional material.

Fully Soft 3D-Printed Electroactive Fluidic Valve for Soft Hydraulic Robots.

PubMed

Zatopa, Alex; Walker, Steph; Menguc, Yigit

2018-06-01

Soft robots are designed to utilize their compliance and contortionistic abilities to both interact safely with their environment and move through it in ways a rigid robot cannot. To more completely achieve this, the robot should be made of as many soft components as possible. Here we present a completely soft hydraulic control valve consisting of a 3D-printed photopolymer body with electrorheological (ER) fluid as a working fluid and gallium-indium-tin liquid metal alloy as electrodes. This soft 3D-printed ER valve weighs less than 10 g and allows for onboard actuation control, furthering the goal of an entirely soft controllable robot. The soft ER valve pressure-holding capabilities were tested under unstrained conditions, cyclic valve activation, and the strained conditions of bending, twisting, stretching, and indentation. It was found that the max holding pressure of the valve when 5 kV was applied across the electrodes was 264 kPa, and that the holding pressure deviated less than 15% from the unstrained max holding pressure under all strain conditions except for indentation, which had a 60% max pressure increase. In addition, a soft octopus-like robot was designed, 3D printed, and assembled, and a soft ER valve was used to stop the fluid flow, build pressure in the robot, and actuate six tentacle-like soft bending actuators.

Electrical and Electrorheological Properties of Alumina/Natural Rubber (STR XL) Composites

PubMed Central

Tangboriboon, Nuchnapa; Uttanawanit, Nuttapot; Longtong, Mean; Wongpinthong, Piraya; Sirivat, Anuvat; Kunanuruksapong, Ruksapong

2010-01-01

The electrorheological properties (ER) of natural rubber (XL)/alumina (Al2O3) composites were investigated in oscillatory shear mode under DC electrical field strengths between 0 to 2 kV/mm. SEM micrographs indicate a mean particle size of 9.873 ± 0.034 µm and particles that are moderately dispersed in the matrix. The XRD patterns indicate Al2O3 is of the β-phase polytype which possesses high ionic conductivity. The storage modulus (G′) of the composites, or the rigidity, increases by nearly two orders of magnitude, with variations in particle volume fraction and electrical field strength. The increase in the storage modulus is caused the ionic polarization of the alumina particles and the induced dipole moments set up in the natural rubber matrix.

Results of investigation at the Miravalles geothermal field, Costa Rica. Resultados de las investigaciones en el campo geotermico de Miravalles, Costa Rica; Parte 2, Muestreo de fluidos pozo abajo

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

Grigsby, C.O.; Goff, F.; Trujillo, P.E. Jr.

Samples of the geothermal fluids in the Miravalles, Costa Rica, geothermal system were collected from production wellbores using downhole fluid samplers, from flowing wellheads using miniseparators, and from hot springs that discharge in the area. The reservoir fluid at Miravalles is a neutral-chloride-type water, but fumaroles and acid-sulfate springs are present within the main thermal area, and there are bicarbonate-rich hot springs that are clearly related to the neutral-chloride reservoir fluids. Dissolved gases are primarily a mixture of CO{sub 2} with air, but samples collected in the fumarolic areas also contain H{sub 2}S. Water-stable isotope analyses suggest local meteoric recharge,more » and the reservoir fluid shows oxygen isotopic shifts of about 2.5% due to high-temperature oxygen exchange between water and rock. Chemical geothermometer temperatures are consistent with the measured downhole temperature of 220{degrees} to 255{degrees}C. This pattern of neutral-chloride reservoir fluids with acid-sulfate springs near the source region and bicarbonate-rich chloride hot springs at the periphery of the system suggests a lateral outflow type of hydrothermal system. In addition to the geochemical evidence, temperature profiles from several of the wells show temperature reversals that are characteristic of lateral outflow plumes. We find no evidence for the underlying, higher temperature (300{degrees}C) system, which has been suggested by other investigators. 24 refs., 14 figs., 6 tabs.« less

Electrorheological effect and electro-optical properties of side-on liquid crystalline polysiloxane in a nematic solvent.

PubMed

Kaneko, Kosuke; Oto, Kodai; Kawai, Toshiaki; Choi, Hyunseok; Kikuchi, Hirotsugu; Nakamura, Naotake

2013-08-26

The electrorheological (ER) effect and the electro-optical properties of a ''side-on'' liquid crystalline polysiloxane (PS) are investigated. A large ER effect is observed and the response to the shear stress of neat PS in the nematic phase is shown to be affected by the shear rate. PS is also mixed with a low-molar nematic liquid crystal (5CB) in order to improve the response behavior to the applied electric field. The rheological properties of such mixtures are highly dependent on the concentration of 5CB. The composites respond faster to the applied electric field and have improved electro-optical properties. This study offers a new perspective on the development of liquid crystal materials for the ER effect. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An Unconventional Inchworm Actuator Based on PZT/ERFs Control Technology

PubMed Central

Liu, Guojun; Zhang, Yanyan; Liu, Jianfang; Li, Jianqiao; Tang, Chunxiu; Wang, Tengfei; Yang, Xuhao

2016-01-01

An unconventional inchworm actuator for precision positioning based on piezoelectric (PZT) actuation and electrorheological fluids (ERFs) control technology is presented. The actuator consists of actuation unit (PZT stack pump), fluid control unit (ERFs valve), and execution unit (hydraulic actuator). In view of smaller deformation of PZT stack, a new structure is designed for actuation unit, which integrates the advantages of two modes (namely, diaphragm type and piston type) of the volume changing of pump chamber. In order to improve the static shear yield strength of ERFs, a composite ERFs valve is designed, which adopts the series-parallel plate compound structure. The prototype of the inchworm actuator has been designed and manufactured in the lab. Systematic test results indicate that the displacement resolution of the unconventional inchworm actuator reaches 0.038 μm, and the maximum driving force and velocity are 42 N, 14.8 mm/s, respectively. The optimal working frequency for the maximum driving velocity is 120 Hz. The complete research and development processes further confirm the feasibility of developing a new type of inchworm actuator with high performance based on PZT actuation and ERFs control technology, which provides a reference for the future development of a new type of actuator. PMID:27022234

An Unconventional Inchworm Actuator Based on PZT/ERFs Control Technology.

PubMed

Liu, Guojun; Zhang, Yanyan; Liu, Jianfang; Li, Jianqiao; Tang, Chunxiu; Wang, Tengfei; Yang, Xuhao

2016-01-01

An unconventional inchworm actuator for precision positioning based on piezoelectric (PZT) actuation and electrorheological fluids (ERFs) control technology is presented. The actuator consists of actuation unit (PZT stack pump), fluid control unit (ERFs valve), and execution unit (hydraulic actuator). In view of smaller deformation of PZT stack, a new structure is designed for actuation unit, which integrates the advantages of two modes (namely, diaphragm type and piston type) of the volume changing of pump chamber. In order to improve the static shear yield strength of ERFs, a composite ERFs valve is designed, which adopts the series-parallel plate compound structure. The prototype of the inchworm actuator has been designed and manufactured in the lab. Systematic test results indicate that the displacement resolution of the unconventional inchworm actuator reaches 0.038 μm, and the maximum driving force and velocity are 42 N, 14.8 mm/s, respectively. The optimal working frequency for the maximum driving velocity is 120 Hz. The complete research and development processes further confirm the feasibility of developing a new type of inchworm actuator with high performance based on PZT actuation and ERFs control technology, which provides a reference for the future development of a new type of actuator.

The electrorheological performance of polyaniline-based hybrid particles suspensions in silicone oil: influence of the dispersing medium viscosity

NASA Astrophysics Data System (ADS)

Roman, C.; García-Morales, M.; Goswami, S.; Marques, A. C.; Cidade, M. T.

2018-07-01

The potential of electrorheological (ER) suspensions based on polarizable particles in simple liquids relies on the particles arrangements which turn their quasi Newtonian behavior into gel-like. However, minor attention has been paid to the effect provoked by the liquid viscosity on the ease of orientation and assembly of the particles. With this aim, a study on the ER behavior, at 25 °C, of 1 wt% suspensions of polyaniline (PANI)-based hybrid particles (—graphene or —tungstene oxide) in silicone oil with varying viscosities (20, 50 and 100 cSt) was carried out. The electric field effect was higher for the PANI-graphene particles suspension in the less viscous silicone oil. However, two drawbacks were observed: (a) higher leakage current flows; and (b) reduced reversibility upon the electric field was turned off. The use of silicone oil with higher viscosity solved these issues.

Multi-coated spheres: recommended electrorheological particles

NASA Astrophysics Data System (ADS)

Wu, C. W.; Conrad, H.

1998-11-01

This paper considers the design of electrorheological (ER) particles. Multi-coated particles suspended in insulating (very weakly conducting) oil are recommended for obtaining high-performance ER suspensions. Only the outer two coatings determine the ER strength. The outermost coating should be a material with high dielectric constant, high electrical breakdown strength and a reasonable level of conductivity. The coating immediately below should be a highly conducting material. The inner coatings, including the core (which can be void), can be of any material having such a density that the composite particle has substantially the same density as the host liquid. Our analysis gives that multi-coated particles can have an ER shear strength as high as 29 kPa when the volume fraction of particles is 0.4 and the applied field is 5 kV 0022-3727/31/22/021/img5. Results in the literature provide support for the concept and analysis.

On-Command Force and Torque Impeding Devices (OC-FTID) Using ERF

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart

2014-01-01

Various machines have been developed to address the need for countermeasures of bone and muscle deterioration when humans operate over extended time in space. Even though these machines are in use, each of them has many limitations that need to be addressed in an effort to prepare for human missions to distant bodies in the solar system. An exercise exoskeleton was conceived that performs on-demand resistivity by inducing force and torque impedance via ElectroRheological Fluid (ERF). The resistive elements consist of pistons that are moving inside ERF-filled cylinders or a donut-shaped cavity, and the fluid flows through the piston when the piston is moved. Tests of the operation of ERF against load showed the feasibility of this approach. ERF properties of high yield stress, low current density, and fast response (less than one millisecond) offer essential characteristics for the construction of the exoskeleton. ERFs can apply very high electrically controlled resistive forces or torque while their size (weight and geometric parameters) can be very small. Their long life and ability to function in a wide temperature range (from -40 to 200 C) allows for their use in extreme environments. ERFs are also nonabrasive, non-toxic, and nonpolluting (meet health and safety regulations). The technology is applicable as a compact exercise machine for astronauts' countermeasure of microgravity, an exercise machine for sport, or as a device for rehabilitation of patients with limb issues.

Nanotechnology research for aerospace applications

NASA Astrophysics Data System (ADS)

Agee, Forrest J.; Lozano, Karen; Gutierrez, Jose M.; Chipara, Mircea; Thapa, Ram; Chow, Alice

2009-04-01

Nanotechnology is impacting the future of the military and aerospace. The increasing demands for high performance and property-specific applications are forcing the scientific world to take novel approaches in developing programs and accelerating output. CONTACT or Consortium for Nanomaterials for Aerospace Commerce and Technology is a cooperative nanotechnology research program in Texas building on an infrastructure that promotes collaboration between universities and transitioning to industry. The participants of the program include the US Air Force Research Laboratory (AFRL), five campuses of the University of Texas (Brownsville, Pan American, Arlington, Austin, and Dallas), the University of Houston, and Rice University. Through the various partnerships between the intellectual centers and the interactions with AFRL and CONTACT's industrial associates, the program represents a model that addresses the needs of the changing and competitive technological world. Into the second year, CONTACT has expanded to twelve projects that cover four areas of research: Adaptive Coatings and Surface Engineering, Nano Energetics, Electromagnetic Sensors, and Power Generation and Storage. This paper provides an overview of the CONTACT program and its projects including the research and development of new electrorheological fluids with nanoladen suspensions and composites and the potential applications.

Dynamic Electrorheological Effects of Rotating Particles:

NASA Astrophysics Data System (ADS)

Yu, K. W.; Gu, G. Q.; Huang, J. P.; Xiao, J. J.

Particle rotation leads to a steady-state which is different from the equilibrium state in the absence of rotational motion. The change of the polarization of the particle due to the rotational motion is called the dynamic electrorheological effect (DER). There are three cases to be considered: rotating particles in a dc field, particle rotation due to a rotating field and spontaneous rotation of particle in dc field (Quincke rotation). In the DER of rotating particles, the particle rotational motion generally reduces the interparticle force between the particles. The effect becomes pronounced when the frequency is on the order of the relaxation rate of the surface charges. In the electrorotation of particles, the mutual interaction between approaching particles will change the electrorotation spectrum significantly. The electrorotation spectrum depends strongly on the medium conductivity as well as the conductivity contrast between the particle and the medium. In the collective behaviors of Quincke rotors, the mutual interactions between the individual rotors lead to the assembly of chain-like structures which make an angle with the applied field. This has an implication of a new class of material.

Electrorheology leads to healthier and tastier chocolate.

PubMed

Tao, Rongjia; Tang, Hong; Tawhid-Al-Islam, Kazi; Du, Enpeng; Kim, Jeongyoo

2016-07-05

Chocolate is one of the most popular food types and flavors in the world. Unfortunately, at present, chocolate products contain too much fat, leading to obesity. Although this issue was called into attention decades ago, no actual solution was found. To bypass this critical outstanding problem, two manufacturers introduced some low-calorie fats to substitute for cocoa butter. Somehow, their products are not allowed in most countries. Here we show that this issue is deeply related to the basic science of soft matter, especially to the viscosity of liquid suspension and maximally random jammed (MRJ) density. When the concentration of cocoa solid is high, close to the MRJ density, removing a small amount of fat will jam the chocolate flow. Applying unconventional electrorheology to liquid chocolate with applied field in the flow direction, we aggregate the cocoa particles into prolate spheroids in micrometers. This microstructure change breaks the rotational symmetry, reduces liquid chocolate's viscosity along the flow direction, and increases its MRJ density significantly. Hence the fat level in chocolate can be effectively reduced. We are expecting a new class of healthier and tastier chocolate soon.

Electrorheology leads to healthier and tastier chocolate

PubMed Central

Tao, Rongjia; Tang, Hong; Tawhid-Al-Islam, Kazi; Du, Enpeng; Kim, Jeongyoo

2016-01-01

Chocolate is one of the most popular food types and flavors in the world. Unfortunately, at present, chocolate products contain too much fat, leading to obesity. Although this issue was called into attention decades ago, no actual solution was found. To bypass this critical outstanding problem, two manufacturers introduced some low-calorie fats to substitute for cocoa butter. Somehow, their products are not allowed in most countries. Here we show that this issue is deeply related to the basic science of soft matter, especially to the viscosity of liquid suspension and maximally random jammed (MRJ) density. When the concentration of cocoa solid is high, close to the MRJ density, removing a small amount of fat will jam the chocolate flow. Applying unconventional electrorheology to liquid chocolate with applied field in the flow direction, we aggregate the cocoa particles into prolate spheroids in micrometers. This microstructure change breaks the rotational symmetry, reduces liquid chocolate’s viscosity along the flow direction, and increases its MRJ density significantly. Hence the fat level in chocolate can be effectively reduced. We are expecting a new class of healthier and tastier chocolate soon. PMID:27325758

Air elimination capability in rapid infusion systems.

PubMed

Zoremba, N; Gruenewald, C; Zoremba, M; Rossaint, R; Schaelte, G

2011-11-01

Pressure infusion devices are used in clinical practice to apply large volumes of fluid over a short period of time. Although air infusion is a major complication, they have limited capability to detect and remove air during pressure infusion. In this investigation, we tested the air elimination capabilities of the Fluido(®) (The Surgical Company), Level 1(®) (Level 1 Technologies Inc.) and Ranger(®) (Augustine Medical GmbH) pressure infusion devices. Measurements were undertaken with a crystalloid solution during an infusion flow of 100, 200, 400 and 800 ml.min(-1). Four different volumes of air (25, 50, 100 and 200 ml) were injected as boluses in one experimental setting, or infused continuously over the time needed to perfuse 2 l saline in the other setting. The perfusion fluid was collected in an airtight infusion bag and the amount of air obtained in the bag was measured. The delivered air volume was negligible and would not cause any significant air embolism in all experiments. In our experimental setting, we found, during high flow, an increased amount of uneliminated air in all used devices compared with lower perfusion flows. All tested devices had a good air elimination capability. The use of ultrasonic air detection coupled with an automatic shutoff is a significant safety improvement and can reliably prevent accidental air embolism at rapid flows. © 2011 The Authors. Anaesthesia © 2011 The Association of Anaesthetists of Great Britain and Ireland.

Electric-field induced phase transitions of dielectric colloids: Impact of multiparticle effects

NASA Astrophysics Data System (ADS)

Wood, Jeffery A.; Docoslis, Aristides

2012-05-01

The thermodynamic framework for predicting the electric-field induced fluid like-solid like phase transition of dielectric colloids developed by Khusid and Acrivos [Phys. Rev. E. 54, 5428 (1996)] is extended to examine the impact of multiscattering/multiparticle effects on the resulting phase diagrams. This was accomplished using effective permittivity models suitable both over the entire composition region for hard spheres (0≤c

The negative and positive electrorheological behavior and vibration damping characteristics of colemanite and polyindene/colemanite conducting composite

NASA Astrophysics Data System (ADS)

Cetin, B.; Unal, H. I.; Erol, O.

2012-12-01

In this study, the electrorheological (ER) properties of colemanite and polyindene (94.8% PIn)/colemanite (5.2%) conducting composite were investigated by dispersion in silicone oil (SO). The zeta (ζ)-potentials and antisedimentation ratios of the materials were determined. Some parameters which affect the ER properties of all the dispersions such as the volume fraction, electric field strength (E), shear rate, frequency and temperature were investigated. The rather unusual behavior known as the negative ER effect was observed for colemanite/SO above E = 1.5 kV mm-1 and for PIn/colemanite/SO under all values of the electric field strength even at high volume fraction. This negative ER response was converted to a positive one by the addition of non-ionic surfactant. Furthermore, glycerol was used as a polar promoter and observed to enhance the ER activity of the colemanite/SO system. Creep-recovery tests were applied to all the dispersions studied to investigate their behavior under sustained shear stress. Finally, 28% and 30% vibration damping capacities were achieved using an automobile shock absorber for the glycerol/colemanite/SO and non-ionic surfactant/PIn/colemanite/SO systems under the E = 0.17 kV mm-1 condition, respectively.

Self-assembly preparation of SiO2@Ni-Al layered double hydroxide composites and their enhanced electrorheological characteristics

PubMed Central

Ji, Xuqiang; Zhang, Wenling; Shan, Lei; Tian, Yu; Liu, Jingquan

2015-01-01

The core-shell structured SiO2@Ni-Al layered double hydroxide (LDH) composites were prepared via self-assembly of Ni-Al LDH on the surface of SiO2 spheres. Only coating a layer of ultrathin Ni-Al LDH sheet, the resulting SiO2@Ni-Al LDH composites exhibit significantly enhanced electrorheological (ER) characteristics compared to conventional bare SiO2 spheres. The monodispersed SiO2 spheres with average diameters of 260 nm were synthesized by the hydrolysis of tetraethyl orthosilicate (TEOS), while the shell part, Ni-Al LDH sheet was prepared by the hydrothermal procedure. The morphology of the samples was investigated via scanning transmission electron microscopy (STEM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The structure of the samples was characterized by X-ray diffraction (XRD). The species and distribution of elements in samples were confirmed by X-ray photoelectron spectroscopy (XPS), Energy dispersive analysis of X-ray (EDX) and elemental mapping in STEM. Subsequently, the ER characteristics of the composites dispersed in insulating oil were characterized by a rotational rheometer. The electric field-stimulated rheological performances (yield stress, viscosity, modulus, etc.) were observed under an external electric field, which is different from the Newtonian state in the free electric field. PMID:26670467

Self-assembly preparation of SiO2@Ni-Al layered double hydroxide composites and their enhanced electrorheological characteristics

NASA Astrophysics Data System (ADS)

Ji, Xuqiang; Zhang, Wenling; Shan, Lei; Tian, Yu; Liu, Jingquan

2015-12-01

The core-shell structured SiO2@Ni-Al layered double hydroxide (LDH) composites were prepared via self-assembly of Ni-Al LDH on the surface of SiO2 spheres. Only coating a layer of ultrathin Ni-Al LDH sheet, the resulting SiO2@Ni-Al LDH composites exhibit significantly enhanced electrorheological (ER) characteristics compared to conventional bare SiO2 spheres. The monodispersed SiO2 spheres with average diameters of 260 nm were synthesized by the hydrolysis of tetraethyl orthosilicate (TEOS), while the shell part, Ni-Al LDH sheet was prepared by the hydrothermal procedure. The morphology of the samples was investigated via scanning transmission electron microscopy (STEM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The structure of the samples was characterized by X-ray diffraction (XRD). The species and distribution of elements in samples were confirmed by X-ray photoelectron spectroscopy (XPS), Energy dispersive analysis of X-ray (EDX) and elemental mapping in STEM. Subsequently, the ER characteristics of the composites dispersed in insulating oil were characterized by a rotational rheometer. The electric field-stimulated rheological performances (yield stress, viscosity, modulus, etc.) were observed under an external electric field, which is different from the Newtonian state in the free electric field.

Palpation imaging using a haptic system for virtual reality applications in medicine.

PubMed

Khaled, W; Reichling, S; Bruhns, O T; Boese, H; Baumann, M; Monkman, G; Egersdoerfer, S; Klein, D; Tunayar, A; Freimuth, H; Lorenz, A; Pessavento, A; Ermert, H

2004-01-01

In the field of medical diagnosis, there is a strong need to determine mechanical properties of biological tissue, which are of histological and pathological relevance. Malignant tumors are significantly stiffer than surrounding healthy tissue. One of the established diagnosis procedures is the palpation of body organs and tissue. Palpation is used to measure swelling, detect bone fracture, find and measure pulse, or to locate changes in the pathological state of tissue and organs. Current medical practice routinely uses sophisticated diagnostic tests through magnetic resonance imaging (MRI), computed tomography (CT) and ultrasound (US) imaging. However, they cannot provide direct measure of tissue elasticity. Last year we presented the concept of the first haptic sensor actuator system to visualize and reconstruct mechanical properties of tissue using ultrasonic elastography and a haptic display with electrorheological fluids. We developed a real time strain imaging system for tumor diagnosis. It allows biopsies simultaneously to conventional ultrasound B-Mode and strain imaging investigations. We deduce the relative mechanical properties by using finite element simulations and numerical solution models solving the inverse problem. Various modifications on the haptic sensor actuator system have been investigated. This haptic system has the potential of inducing real time substantial forces, using a compact lightweight mechanism which can be applied to numerous areas including intraoperative navigation, telemedicine, teaching and telecommunication.

Steering of SH wave propagation in electrorheological elastomer with a structured meta-slab by tunable phase discontinuities

NASA Astrophysics Data System (ADS)

Xu, Yanlong; Li, Yi; Cao, Liyun; Yang, Zhichun; Zhou, Xiaoling

2017-09-01

The generalized Snell's law (GSL) with phase discontinuity proposed based on the concept of a metasurface, which can be used to control arbitrarily the reflection and refraction of waves, attracts a growing attention in these years. The concept of abnormally deflecting the incident wave has been applied to the elastic field very recently. However, most of the studies on metasurfaces are based on passive materials, which restricts the frequency or the deflected angles always working in a single state. Here, we steer elastic SH wave propagation in an electrorheological (ER) elastomer with a structured meta-slab composed of geometrically periodic wave guides by exposing the slab to the programmed electric fields. The dependence of phase velocities of SH waves on the applied electric fields can make the phase shift under the form of a special function along the slab, which will control the refraction angles of the transmitted SH waves by the GSL. Accordingly we design the meta-slab theoretically and conduct corresponding numerical simulations. The results demonstrate that the structured meta-slab under the programmed external electric fields can deflect SH wave flexibly with tunable refraction angles and working frequencies, and can focus SH wave with tunable focal lengths. The present study will broaden the scope of applying adaptive materials to design metasurfaces with tunability.

Stimuli-Responsive Polymer-Clay Nanocomposites under Electric Fields

PubMed Central

Piao, Shang Hao; Kwon, Seung Hyuk; Choi, Hyoung Jin

2016-01-01

This short Feature Article reviews electric stimuli-responsive polymer/clay nanocomposites with respect to their fabrication, physical characteristics and electrorheological (ER) behaviors under applied electric fields when dispersed in oil. Their structural characteristics, morphological features and thermal degradation behavior were examined by X-ray diffraction pattern, scanning electron microscopy and transmission electron microscopy, and thermogravimetric analysis, respectively. Particular focus is given to the electro-responsive ER characteristics of the polymer/clay nanocomposites in terms of the yield stress and viscoelastic properties along with their applications. PMID:28787852

Future automotive materials: Evolution or revolution

NASA Technical Reports Server (NTRS)

Beardmore, P.

1990-01-01

An exciting era is evolving in the application of new materials technologies to automotive applications. The desire on the part of the automobile industry to completely satisfy the customers while concurrently meeting increasing demands and regulations for stringent emission control and fuel efficiency is opening a plethora of opportunities for new materials. In many cases, materials solutions are the only mechanisms for resolving some of the upcoming issues. The materials scientist and engineer will therefore have a primary role to play and will assume a position of significance hithertofore unseen in the automobile industry. The nature of the industry dictates that changes are primarily evolutionary with respect to chronology but nevertheless some of the future material changes will be revolutionary in nature. This presentation will treat three primary systems of the vehicle separately, based on the different materials approaches which will be adopted. These areas are: (1) skin panels, (2) structures, and (3) powertrains. The competition between a variety of new materials in these 3 systems will be discussed in detail with the various tradeoffs being outlined. Amongst the more prominent of the new breed of materials will be new steel technologies, structural plastics (FRP), aluminum alloys (conventional and rapidly solidified), titanium alloys, metal matrix composites and smart materials (electrorheological fluids, etc.). The pace of development and application is accelerating rapidly and the impetus is likely to increase.

Three different methods for the derivation of control laws for multi-degree-of-freedom systems containing electrorheological dampers

NASA Astrophysics Data System (ADS)

Moosheimer, Johannes; Waller, Heinz

1999-06-01

The minimization of unwanted vibrations is an important technical challenge. Purely passive systems often do not achieve the postulated results. Purely active systems are costly because of the required additional power and the necessary maintenance. Currently it seems that semi-active methods of vibration reduction are as competitive as any other methods. Semi-active damping control can be realized with electro- or magnetorheological fluids. These change their characteristic in the presence of an electric or magnetic field or by bypasses combined with magnetic valves. The methods known in linear control theory cannot be used for the controller design because no explicit external forces can be generated whenever they are needed. Forces can only be generated when relative velocities between the endpoints of the damper exist. It is important to investigate control methods which will reduce vibration with controlled damping. In this paper three different methods for establishing control laws are presented. The first is based on the consideration of power flow in the system. It is discussed in detail. The second method uses Bellmans dynamic optimization. The last transforms a multi degree of freedom system by modal analysis into uncoupled single degree of freedom systems. The control methods developed by these three methods all lead to the same vibration reduction strategy. The control laws are verified with simulation results.

Implementacion de modulos constructivistas que atiendan "misconceptions" y lagunas conceptuales en temas de la fisica en estudiantes universitarios

NASA Astrophysics Data System (ADS)

Santacruz Sarmiento, Neida M.

Este estudio se enfoco en los "misconception" y lagunas conceptuales en temas fundamentales de Fisica como son Equilibrio Termodinamico y Estatica de fluidos. En primer lugar se trabajo con la identificacion de "misconceptions" y lagunas conceptuales y se analizo en detalle la forma en que los estudiantes construyen sus propias teorias de fenomenos relacionados con los temas. Debido a la complejidad en la que los estudiantes asimilan los conceptos fisicos, se utilizo el metodo de investigacion mixto de tipo secuencial explicativo en dos etapas, una cuantitativa y otra cualitativa. La primera etapa comprendio cuatro fases: (1) Aplicacion de una prueba diagnostica para identificar el conocimiento previo y lagunas conceptuales. (2) Identificacion de "misconceptions" y lagunas del concepto a partir del conocimiento previo. (3) Implementacion de la intervencion por medio de modulos en el topico de Equilibrio Termodinamico y Estatica de Fluidos. (4) Y la realizacion de la pos prueba para analizar el impacto y la efectividad de la intervencion constructivista. En la segunda etapa se utilizo el metodo de investigacion cualitativo, por medio de una entrevista semiestructurada que partio de la elaboracion de un mapa conceptual y se finalizo con un analisis de datos conjuntamente. El desarrollo de este estudio permitio encontrar "misconceptions" y lagunas conceptuales a partir del conocimiento previo de los estudiantes participantes en los temas trabajados, que fueron atendidos en el desarrollo de las distintas actividades inquisitivas que se presentaron en el modulo constructivista. Se encontro marcadas diferencias entre la pre y pos prueba en los temas, esto se debio al requerimiento de habilidades abstractas para el tema de Estatica de Fluidos y al desarrollo intuitivo para el tema de Equilibrio Termodinamico, teniendo mejores respuestas en el segundo. Los participantes demostraron una marcada evolucion y/o cambio en sus estructuras de pensamiento, las pruebas estadisticas de t-pareada fueron significativas para ambos modulos a pesar que en la pos prueba no todos llegaron a la respuesta correcta. El analisis cualitativo de las respuestas de los participantes confirmo la dificultad de remover "misconception" y lagunas conceptuales.

Nursing knowledge and practices regarding subcutaneous fluid administration.

PubMed

Gomes, Nathália Silva; Silva, Andrea Mara Bernardes da; Zago, Luana Barbosa; Silva, Érica Carneiro de Lima E; Barichello, Elizabeth

2017-01-01

To describe the evidence in the literature regarding the knowledge and practices of the nursing team about subcutaneous administration of drugs and fluids in adults. Integrative review of the literature using the descriptors "nursing", "hypodermoclysis", "drug administration routes", "adult health," and "knowledge," in English, Spanish, and Portuguese, with no publication deadline. Of the 569 articles found, eight made up the sample. A predominance of international journals (75%) with more than five years of publication (62.5%). The analysis of the methodological characteristics showed a predominance of literature reviews (25%), quantitative studies (62.5%), cross-sectional studies (50%), and non-experimental studies (50%). Although it is an old technique with proven efficacy, hypodermoclysis is still little used, a puzzling fact due to its advantages and indications for any age. descrever as evidências, na literatura, sobre os conhecimentos e as práticas da equipe de enfermagem na administração de medicamentos e de fluidos por via subcutânea no adulto. revisão integrativa da literatura utilizando os descritores enfermagem, hipodermóclise, vias de administração de medicamentos, saúde do adulto e conhecimento; nos idiomas inglês, espanhol e português, sem data limite de publicação. Dos 569 artigos encontrados, oito compuseram a amostra. predomínio de revistas internacionais (75%) e com mais de cinco anos de publicação (62,5%). Ao analisarem-se as características metodológicas, predominaram: revisões de literatura (25%), estudos quantitativos (62,5%), estudos transversais (50%) e não-experimentais (50%). apesar de se tratar de uma técnica antiga com eficácia comprovada, a hipodermóclise ainda é pouco utilizada, fato incoerente pelas suas vantagens e suas indicações para qualquer idade.

The Rheological Behavior and Thixotropy of Electrorheological Suspensions in Differing Temperature/Velocity Conditions (Rheologicheskoe Povedenie i Tikostropiya Elektroreologicheskikh Suspenzii v Razlichnykh Temperaturno-Skorostnykh Rezhimakh)

DTIC Science & Technology

1990-10-29

unsuitable for ERS, the low water content (eg for aerosil and diatomite 1-3 wt%) being insufficient to activate them. The ERE starts to appear only beyond a...certain threshold water content adsorbed on the particles in suspension. With further increase in the quantity of adsorbed water the effective...silica-gel particles varies with varying water content In the silica suspensions examined the evidence of ERE was linked to the presence of adsorbed

Electrorheology for energy production and conservation

NASA Astrophysics Data System (ADS)

Huang, Ke

Recently, based on the physics of viscosity, we developed a new technology, which utilizes electric or magnetic fields to change the rheology of complex fluids to reduce the viscosity, while keeping the temperature unchanged. The method is universal and applicable to all complex fluids with suspended particles of nano-meter, submicrometer, or micrometer size. Completely different from the traditional viscosity reduction method, raising the temperature, this technology is energy-efficient, as it only requires small amount of energy to aggregate the suspended particles. In this thesis, we will first discuss this new technology in detail, both in theory and practice. Then, we will report applications of our technology to energy science research. Presently, 80% of all energy sources are liquid fuels. The viscosity of liquid fuels plays an important role in energy production and energy conservation. With an electric field, we can reduce the viscosity of asphalt-based crude oil. This is important and useful for heavy crude oil and off-shore crude oil production and transportation. Especially, since there is no practical way to raise the temperature of crude oil inside the deepwater pipelines, our technology may play a key role in future off-shore crude oil production. Electrorehology can also be used to reduce the viscosity of refinery fuels, such as diesel fuel and gasoline. When we apply this technology to fuel injection, the fuel droplets in the fuel atomization become smaller, leading to faster combustion in the engine chambers. As the fuel efficiency of internal combustion engines depends on the combustion speed and timing, the fast combustion produces much higher fuel efficiency. Therefore, adding our technology on existing engines improves the engine efficiency significantly. A theoretical model for the engine combustion, which explains how fast combustion improves the engine efficiency, is also presented in the thesis. As energy is the key to our national security, we believe that our technology is important and will have a strong impact on energy production and conversation in the future.

A teoria da percolação aplicada às galáxias aneladas peculiares

NASA Astrophysics Data System (ADS)

Poppe, P. C. R.; Martin, V. A. F.; de Medeiros, N. G. F.; Faúndez-Abans, M.; Oliveira-Abans, M.

2003-08-01

Formulado no final da década de 50, o modelo de percolação concentra-se em descrever o meio poroso, que será visto neste trabalho como uma rede de canais aleatórios, por onde escoa um fluido determinístico. Se o número de canais for suficientemente grande, então eles estarão ligados e o meio se tornará permeável à passagem do fluido. Neste caso, dizemos que houve a percolação do fluido. Reformulando o modelo acima, podemos escrever um código particularmente adaptado para simulações em Galáxias, onde iremos supor que os canais formam um reticulado, e que cada sítio da rede representa um poro que será interpretado como uma região ativa de formação estelar. Para cada elo teremos um pequeno canal ligando dois sítios vizinhos, que poderá, após um tempo "t", induzir ou não a formação de uma região ativa no poro vizinho. Para simular a passagem desta região ativa através dos poros, diremos que um elo está aberto com probabilidade p e fechado com probabilidade 1-p. Dessa forma, passamos a imaginar configurações de elos abertos e fechados, onde cada configuração ocorre com uma certa probabilidade, dada por p|A|(1-p)|F|, onde |A| é o número de elos abertos e |F| o número de elos fechados da configuração. A expressão anterior só tem importância física se |A| e |F| forem ambos finitos, pois, caso contrário, a probabilidade de ocorrência de uma dada configuração será sempre nula. Neste trabalho, foram considerados dados cinemáticos publicados na literatura bem como aqueles obtidos pelos autores a partir de observações fotométricas realizadas no Observatório de Las Campanãs, em 1994, para a Galáxia Anelada Peculiar HRG 03401. Mostraremos que para certos valores de p, situados entre 0,5 e 0,6, os clusters assim formados irão simular, de maneira coerente, o referido objeto.

Letters to the Editor

NASA Astrophysics Data System (ADS)

1998-03-01

All the Letters to the Editor in this issue are in the same PostScript or PDF file. Contents Comment on `Magnetic and electric field strengths of high voltage power lines and household appliances' José Luis Giordano Dept. de Ciencia y Tecnología de Materiales y Fluidos, CPSI, Universidad de Zaragoza, Spain Twins paradox S R Carson Norton College, Malton, North Yorkshire, UK On alternative ways of finding the ratio of specific heats of gases Tomas Ficker Physics Department, Technical University of Brno, Czech Republic

Electro fluido dynamic techniques to design instructive biomaterials for tissue engineering and drug delivery

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

Guarino, Vincenzo, E-mail: vguarino@unina.it; Altobelli, Rosaria; Cirillo, Valentina

A large variety of processes and tools is continuously investigated to discover new solutions to design instructive materials with controlled chemical, physical and biological properties for tissue engineering and drug delivery. Among them, electro fluido dynamic techniques (EFDTs) are emerging as an interesting strategy, based on highly flexible and low-cost processes, to revisit old biomaterial’s manufacturing approach by utilizing electrostatic forces as the driving force for the fabrication of 3D architectures with controlled physical and chemical functionalities to guide in vitro and in vivo cell activities. By a rational selection of polymer solution properties and process conditions, EFDTs allow tomore » produce fibres and/or particles at micro and/or nanometric size scale which may be variously assembled by tailored experimental setups, thus giving the chance to generate a plethora of different 3D devices able to incorporate biopolymers (i.e., proteins, polysaccharides) or active molecules (e.g., drugs) for different applications. Here, we focus on the optimization of basic EFDTs - namely electrospinning, electrospraying and electrodynamic atomization - to develop active platforms (i.e., monocomponent, protein and drug loaded scaffolds and µ-scaffolds) made of synthetic (PCL, PLGA) or natural (chitosan, alginate) polymers. In particular, we investigate how to set materials and process parameters to impart specific morphological, biochemical or physical cues to trigger all the fundamental cell–biomaterial and cell– cell cross-talking elicited during regenerative processes, in order to reproduce the complex microenvironment of native or pathological tissues.« less

Electro fluido dynamic techniques to design instructive biomaterials for tissue engineering and drug delivery

NASA Astrophysics Data System (ADS)

Guarino, Vincenzo; Altobelli, Rosaria; Cirillo, Valentina; Ambrosio, Luigi

2015-12-01

A large variety of processes and tools is continuously investigated to discover new solutions to design instructive materials with controlled chemical, physical and biological properties for tissue engineering and drug delivery. Among them, electro fluido dynamic techniques (EFDTs) are emerging as an interesting strategy, based on highly flexible and low-cost processes, to revisit old biomaterial's manufacturing approach by utilizing electrostatic forces as the driving force for the fabrication of 3D architectures with controlled physical and chemical functionalities to guide in vitro and in vivo cell activities. By a rational selection of polymer solution properties and process conditions, EFDTs allow to produce fibres and/or particles at micro and/or nanometric size scale which may be variously assembled by tailored experimental setups, thus giving the chance to generate a plethora of different 3D devices able to incorporate biopolymers (i.e., proteins, polysaccharides) or active molecules (e.g., drugs) for different applications. Here, we focus on the optimization of basic EFDTs - namely electrospinning, electrospraying and electrodynamic atomization - to develop active platforms (i.e., monocomponent, protein and drug loaded scaffolds and µ-scaffolds) made of synthetic (PCL, PLGA) or natural (chitosan, alginate) polymers. In particular, we investigate how to set materials and process parameters to impart specific morphological, biochemical or physical cues to trigger all the fundamental cell-biomaterial and cell- cell cross-talking elicited during regenerative processes, in order to reproduce the complex microenvironment of native or pathological tissues.

Virtual Reality Robotic Operation Simulations Using MEMICA Haptic System

NASA Technical Reports Server (NTRS)

Bar-Cohen, Y.; Mavroidis, C.; Bouzit, M.; Dolgin, B.; Harm, D. L.; Kopchok, G. E.; White, R.

2000-01-01

There is an increasing realization that some tasks can be performed significantly better by humans than robots but, due to associated hazards, distance, etc., only a robot can be employed. Telemedicine is one area where remotely controlled robots can have a major impact by providing urgent care at remote sites. In recent years, remotely controlled robotics has been greatly advanced. The robotic astronaut, "Robonaut," at NASA Johnson Space Center is one such example. Unfortunately, due to the unavailability of force and tactile feedback capability the operator must determine the required action using only visual feedback from the remote site, which limits the tasks that Robonaut can perform. There is a great need for dexterous, fast, accurate teleoperated robots with the operator?s ability to "feel" the environment at the robot's field. Recently, we conceived a haptic mechanism called MEMICA (Remote MEchanical MIrroring using Controlled stiffness and Actuators) that can enable the design of high dexterity, rapid response, and large workspace system. Our team is developing novel MEMICA gloves and virtual reality models to allow the simulation of telesurgery and other applications. The MEMICA gloves are designed to have a high dexterity, rapid response, and large workspace and intuitively mirror the conditions at a virtual site where a robot is simulating the presence of the human operator. The key components of MEMICA are miniature electrically controlled stiffness (ECS) elements and Electrically Controlled Force and Stiffness (ECFS) actuators that are based on the sue of Electro-Rheological Fluids (ERF). In this paper the design of the MEMICA system and initial experimental results are presented.

A state-of-the-art assessment of active structures

NASA Technical Reports Server (NTRS)

1992-01-01

A state-of-the-art assessment of active structures with emphasis towards the applications in aeronautics and space is presented. It is felt that since this technology area is growing at such a rapid pace in many different disciplines, it is not feasible to cover all of the current research but only the relevant work as relates to aeronautics and space. Research in smart actuation materials, smart sensors, and control of smart/intelligent structures is covered. In smart actuation materials, piezoelectric, magnetostrictive, shape memory, electrorheological, and electrostrictive materials are covered. For sensory materials, fiber optics, dielectric loss, and piezoelectric sensors are examined. Applications of embedded sensors and smart sensors are discussed.

Marine hydrogeology: recent accomplishments and future opportunities

NASA Astrophysics Data System (ADS)

Fisher, A. T.

2005-03-01

Marine hydrogeology is a broad-ranging scientific discipline involving the exploration of fluid-rock interactions below the seafloor. Studies have been conducted at seafloor spreading centers, mid-plate locations, and in plate- and continental-margin environments. Although many seafloor locations are remote, there are aspects of marine systems that make them uniquely suited for hydrologic analysis. Newly developed tools and techniques, and the establishment of several multidisciplinary programs for oceanographic exploration, have helped to push marine hydrogeology forward over the last several decades. Most marine hydrogeologic work has focused on measurement or estimation of hydrogeologic properties within the shallow subsurface, but additional work has emphasized measurements of local and global fluxes, fluid source and sink terms, and quantitative links between hydrogeologic, chemical, tectonic, biological, and geophysical processes. In addition to summarizing selected results from a small number of case studies, this paper includes a description of several new experiments and programs that will provide outstanding opportunities to address fundamental hydrogeologic questions within the seafloor during the next 20-30 years. L'hydrogéologie marine est une large discipline scientifique impliquant l' exploration des interactions entre les fluides et les roches sous les fonds marins. Des études ont été menées dans les différents environnements sous-marins (zone abyssale, plaque océanique, marges continentales). Bien que de nombreux fonds marins soient connus, il existe des aspects des systèmes marins qui les rendent inadaptés à l'analyse hydrologique. De nouveaux outils et techniques, et la mise en oeuvre de nombreux programmes multidisciplinaires d'exploration océanographique, ont aidé à pousser en avant l'hydrogéologie marine ces dix dernières années. La plus part des études hydrogéologiques se sont concentrées jusqu'à présent sur la mesure ou l'estimation des propriétés à la sub-surface des fonds marins, et des travaux complémentaires ont mis en valeur les mesures de flux, local ou global, de termes « sources » et « pertes », et des liens quantitatifs entre l'hydrogéologie, la chimie, la tectonique, la biologie, et les processus géophysiques. Cet article vise à résumer des résultats sélectionnés parmi un petit nombre d'études, et à décrire plusieurs nouvelles expériences et programmes, qui sont autant d'opportunités pour répondre aux questions fondamentales relatives aux fonds marins, posées ces dernières 20-30 années. La hidrogeología marina es una disciplina científica de amplios alcances que involucra la exploración de interacciones fluido-roca por debajo del fondo del mar. Se han llevado a cabo estudios en centros de expansión del fondo del mar, lugares en medio de una placa, y en ambientes de placa y margen continental. Aunque muchos sitios en el fondo del mar son remotos, existen aspectos de estos sistemas marinos que los hacen particularmente adaptables para análisis hidrológico. Nuevas técnicas y herramientas desarrolladas, y el establecimiento de varios programas multidisciplinarios para exploración oceanográfica, han ayudado a impulsar la hidrogeología marina hacia delante durante las ultimas décadas. La mayor parte del trabajo hidrogeológico marino se ha enfocado en la medición o estimación de propiedades hidrogeológicas dentro del subsuelo superficial, pero trabajo adicionalha enfatizado mediciones de flujos globales y locales, términos de fuente y sumidero de fluidos, y vínculos cuantitativos entre procesos hidrogeológicos, químicos, tectónicos, biológicos y geofísicos. Además de resumir resultados seleccionados de un número pequeño de estudios de caso, este artículo incluye una descripción de varios programas y experimentos nuevos que aportarán oportunidades excepcionales para dirigir preguntas hidrogeológicas fundamentales dentro del fondo oceánico durante los siguientes 20-30 años.

The Response of Starch/gelatin/glycerin Aqueous Electrorheological Elastomer to Applied Electric Field

NASA Astrophysics Data System (ADS)

Gao, Lingxiang; Zhao, Xiaopeng

The aqueous ER elastomers, containing crude organic starch particles which dispersed in gelatin/glycerin/water matrix, were prepared with or without the applied DC electric field. The responses of the composite systems to the electric field were tested by the compression modulus and resistance of the elastomers. The result shows that they are enhanced and controlled evidently under an applied DC electric field. The strongest responses appear at 25% weight fraction of starch. In addition, the increment modulus of the elastomer increases with the strength of the applied field within 0.5~1.5 kV/mm, while after the field is stronger than 1.5 kV/mm it doesn't increase with field, appearing "saturation".

Profile of Brazilian workers victims of occupational accidents with biological fluids.

PubMed

Miranda, Fernanda Moura D'Almeida; Cruz, Elaine Drehmer de Almeida; Félix, Jorge Cestari Vinícius; Kalinke, Luciana Puchalski; Mantovani, Maria de Fátima; Sarquis, Leila Maria Mansano

2017-01-01

To characterize the Brazilian workers victims of occupational accidents with biological fluids. Epidemiological and descriptive research, in which 284,877 notifications of the Notifiable Diseases Information System were analyzed between 2007 and 2014. We used Stata 13 for data analysis. The highest incidence density occurred in females with 0.8 cases per 1,000 workers/year (n = 222,042, 77.9%); in the age group of 20 to 24 years old, with 0.6 cases per 1,000 workers/year (n = 64,221, 23.3%); with some high school and some college, with 0.6 cases per 1,000 workers/year (n = 141,275, 49.6%). We found that these accidents occurred among 23 occupational subgroups. For the most part, the workers had an employment relationship and had issued the Occupational Accident Notification. It is necessary to rethink the measures of orientation to workers regarding the risks and relative prophylaxis for these accidents, with the aim of reducing them. Caracterizar os trabalhadores brasileiros vítimas de acidente de trabalho com fluidos biológicos. Pesquisa epidemiológica, descritiva, na qual foram analisadas 284.877 notificações do Sistema Nacional de Notificação de Agravos, entre 2007 e 2014. Utilizou-se Stata 13 para a análise dos dados. A maior densidade de incidência ocorreu no sexo feminino com 0,8 caso a cada 1.000 trabalhadores/ano (n = 222.042; 77,9%); na faixa etária de 20 a 24 anos com 0,6 caso a cada 1.000 trabalhadores/ano (n = 64.221; 23,3%); com Ensino Médio e Superior incompleto com 0,6 caso a cada 1.000 trabalhadores/ano (n = 141.275; 49,6%). Verificou-se que esses acidentes ocorreram entre 23 subgrupos ocupacionais. Em sua maioria, os trabalhadores possuíam vínculo empregatício e tiveram emitida a Comunicação de Acidente de Trabalho. Faz-se necessário repensar as medidas de orientação aos trabalhadores quanto aos riscos e profilaxia relativa para estes acidentes, visando reduzi-los ou diminui-los.

UNDERSTANDING THE INTERNATIONAL CONSENSUS FOR ACUTE PANCREATITIS: CLASSIFICATION OF ATLANTA 2012.

PubMed

Souza, Gleim Dias de; Souza, Luciana Rodrigues Queiroz; Cuenca, Ronaldo Máfia; Jerônimo, Bárbara Stephane de Medeiros; Souza, Guilherme Medeiros de; Vilela, Vinícius Martins

2016-01-01

Contrast computed tomography and magnetic resonance imaging are widely used due to its image quality and ability to study pancreatic and peripancreatic morphology. The understanding of the various subtypes of the disease and identification of possible complications requires a familiarity with the terminology, which allows effective communication between the different members of the multidisciplinary team. Demonstrate the terminology and parameters to identify the different classifications and findings of the disease based on the international consensus for acute pancreatitis ( Atlanta Classification 2012). Search and analysis of articles in the "CAPES Portal de Periódicos with headings "acute pancreatitis" and "Atlanta Review". Were selected 23 articles containing radiological descriptions, management or statistical data related to pathology. Additional statistical data were obtained from Datasus and Population Census 2010. The radiological diagnostic criterion adopted was the Radiology American College system. The "acute pancreatitis - 2012 Rating: Review Atlanta classification and definitions for international consensus" tries to eliminate inconsistency and divergence from the determination of uniformity to the radiological findings, especially the terminology related to fluid collections. More broadly as "pancreatic abscess" and "phlegmon" went into disuse and the evolution of the collection of patient fluids can be described as "acute peripancreatic collections", "acute necrotic collections", "pseudocyst" and "necrosis pancreatic walled or isolated". Computed tomography and magnetic resonance represent the best techniques with sequential images available for diagnosis. Standardization of the terminology is critical and should improve the management of patients with multiple professionals care, risk stratification and adequate treatment. A tomografia computadorizada contrastada e a ressonância magnética são exames amplamente utilizados no estudo da morfologia pancreática e peripancreática. O entendimento dos diversos subtipos da doença e identificação de suas possíveis complicações requer familiaridade com a terminologia padrão, a qual permite comunicação efetiva entre os diversos membros da equipe multidisciplinar. Demonstrar terminologia e os parâmetros para identificação das diferentes classificações da doença a partir do consenso internacional para as pancreatites agudas (Classificação de Atlanta 2012. Busca e análise de artigos no "Portal de Periódicos da CAPES" com descritores "pancreatite aguda" e "Revisão de Atlanta". : Foram selecionados 23 artigos que continham descrições radiológicas, manejo ou dados estatísticos relacionados à doença. Dados estatísticos adicionais foram obtidos no sistema Datasus e Censo Demográfico 2010. O critério de diagnóstico radiológico adotado foi o do Colégio Americano de Radiologia. A "Classificação da pancreatite aguda - 2012: revisão da classificação de Atlanta e definições por consenso internacional" tenta eliminar a inconsistência e divergências a partir da determinação de uniformidade para os achados radiológicos, em especial à terminologia relacionada às coleções de fluidos. Termos mais abrangentes como "abscesso pancreático" e "flegmão" entraram em desuso e a evolução da coleção de fluidos pode ser descrita como: "coleções peripancreáticas agudas", "coleções necróticas agudas", "pseudocisto" e "necrose pancreática murada ou isolada". A tomografia computadorizada e a ressonância magnética representam as melhores técnicas com cortes sequenciais disponíveis para diagnóstico. A adequação da terminologia é ponto crítico e deve permitir o manejo do paciente por múltiplos profissionais, estratificação de risco e adequação de tratamento.

Electrostatic separation of superconducting particles from non-superconducting particles and improvement in fuel atomization by electrorheology

NASA Astrophysics Data System (ADS)

Chhabria, Deepika

This thesis has two major topics: (1) Electrostatic Separation of Superconducting Particles from a Mixture of Non-Superconducting Particles. (2) Improvement in fuel atomization by Electrorheology. (1) Based on the basic science research, the interactions between electric field and superconductors, we have developed a new technology, which can separate superconducting granular particles from their mixture with non-superconducting particles. The electric-field induced formation of superconducting balls is important aspect of the interaction between superconducting particles and electric field. When the applied electric field exceeds a critical value, the induced positive surface energy on the superconducting particles forces them to aggregate into balls or cling to the electrodes. In fabrication of superconducting materials, especially HTSC materials, it is common to come across materials with multiple phases: some grains are in superconducting state while the others are not. Our technology is proven to be very useful in separating superconducting grains from the rest non-superconducting materials. To separate superconducting particles from normal conducting particles, we apply a suitable strong electric field. The superconducting particles cling to the electrodes, while normal conducting particles bounce between the electrodes. The superconducting particles could then be collected from the electrodes. To separate superconducting particles from insulating ones, we apply a moderate electric field to force insulating particles to the electrodes to form short chains while the superconducting particles are collected from the middle of capacitor. The importance of this technology is evidenced by the unsuccessful efforts to utilize the Meissner effect to separate superconducting particles from nonsuperconducting ones. Because the Meissner effect is proportional to the particle volume, it has been found that the Meissner effect is not useful when the superconducting particles are smaller than 45mum. One always come across multiphase superconducting materials where most superconducting grains are much smaller than 45mum. On the other hand, since our technology is based on the surface effect, it gets stronger when the particles become smaller. Our technology is thus perfect for small superconducting particles and for fabrication of HTSC materials. The area of superconductivity is expected to be very important for 21 st Century energy industry. The key for this development is the HTSC materials. We, therefore, expect that our technology will have strong impact in the area. (2) Improving engine efficiency and reducing pollutant emissions are extremely important. Here we report our fuel injection technology based on new physics principle that proper application of electrorheology can reduce the viscosity of petroleum fuels. A small device is thus introduced just before the fuel injection for the engine, producing a strong electric field to reduce the fuel viscosity, resulting in much smaller fuel droplets in atomization. As combustion starts at the interface between fuel and air and most harmful emissions are coming from incomplete burning, reducing the size of fuel droplets would increase the total surface area to start burning, leading to a cleaner and more efficient engine. This concept has been widely accepted as the discussions about future engine for efficient and clean combustion are focused on ultra-dilute mixtures at extremely high pressure to produce much finer mist of fuel for combustion. The technology is expected to have broad applications, applicable to current internal combustion engines and future engines as well.

Energy variational analysis of ions in water and channels: Field theory for primitive models of complex ionic fluids

PubMed Central

Eisenberg, Bob; Hyon, YunKyong; Liu, Chun

2010-01-01

Ionic solutions are mixtures of interacting anions and cations. They hardly resemble dilute gases of uncharged noninteracting point particles described in elementary textbooks. Biological and electrochemical solutions have many components that interact strongly as they flow in concentrated environments near electrodes, ion channels, or active sites of enzymes. Interactions in concentrated environments help determine the characteristic properties of electrodes, enzymes, and ion channels. Flows are driven by a combination of electrical and chemical potentials that depend on the charges, concentrations, and sizes of all ions, not just the same type of ion. We use a variational method EnVarA (energy variational analysis) that combines Hamilton’s least action and Rayleigh’s dissipation principles to create a variational field theory that includes flow, friction, and complex structure with physical boundary conditions. EnVarA optimizes both the action integral functional of classical mechanics and the dissipation functional. These functionals can include entropy and dissipation as well as potential energy. The stationary point of the action is determined with respect to the trajectory of particles. The stationary point of the dissipation is determined with respect to rate functions (such as velocity). Both variations are written in one Eulerian (laboratory) framework. In variational analysis, an “extra layer” of mathematics is used to derive partial differential equations. Energies and dissipations of different components are combined in EnVarA and Euler–Lagrange equations are then derived. These partial differential equations are the unique consequence of the contributions of individual components. The form and parameters of the partial differential equations are determined by algebra without additional physical content or assumptions. The partial differential equations of mixtures automatically combine physical properties of individual (unmixed) components. If a new component is added to the energy or dissipation, the Euler–Lagrange equations change form and interaction terms appear without additional adjustable parameters. EnVarA has previously been used to compute properties of liquid crystals, polymer fluids, and electrorheological fluids containing solid balls and charged oil droplets that fission and fuse. Here we apply EnVarA to the primitive model of electrolytes in which ions are spheres in a frictional dielectric. The resulting Euler–Lagrange equations include electrostatics and diffusion and friction. They are a time dependent generalization of the Poisson–Nernst–Planck equations of semiconductors, electrochemistry, and molecular biophysics. They include the finite diameter of ions. The EnVarA treatment is applied to ions next to a charged wall, where layering is observed. Applied to an ion channel, EnVarA calculates a quick transient pile-up of electric charge, transient and steady flow through the channel, stationary “binding” in the channel, and the eventual accumulation of salts in “unstirred layers” near channels. EnVarA treats electrolytes in a unified way as complex rather than simple fluids. Ad hoc descriptions of interactions and flow have been used in many areas of science to deal with the nonideal properties of electrolytes. It seems likely that the variational treatment can simplify, unify, and perhaps derive and improve those descriptions. PMID:20849161

Integrating geophysical and hydrochemical borehole-log measurements to characterize the Chalk aquifer, Berkshire, United Kingdom

NASA Astrophysics Data System (ADS)

Schürch, Marc; Buckley, David

2002-09-01

Geophysical and hydrochemical borehole-logging techniques were integrated to characterize hydraulic and hydrogeochemical properties of the Chalk aquifer at boreholes in Berkshire, UK. The down-hole measurements were made to locate fissures in the chalk, their spatial extent between boreholes, and to determine the groundwater chemical quality of the water-bearing layers. The geophysical borehole logging methods used were caliper, focused resistivity, induction resistivity, gamma ray, fluid temperature, fluid electrical conductivity, impeller and heat-pulse flowmeter, together with borehole wall optical-imaging. A multiparameter data transmitter was used to measure groundwater temperature, electrical conductivity, dissolved oxygen, pH, and redox potential of the borehole fluid down-hole. High permeability developed at the Chalk Rock by groundwater circulation provides the major flow horizon at the Banterwick Barn study site and represents a conduit system that serves as an effective local hydraulic connection between the boreholes. The Chalk Rock includes several lithified solution-ridden layers, hardgrounds, which imply a gap in sedimentation possibly representing an unconformity. Lower groundwater temperature, high dissolved-oxygen content, and flowmeter evidence of preferential groundwater flow in the Chalk Rock indicated rapid groundwater circulation along this horizon. By repeating the logging at different times of the year under changing hydraulic conditions, other water-inflow horizons within the Chalk aquifer were recognized. Résumé. Des techniques géophysiques et hydrochimiques de diagraphies en forage ont été mises en oeuvre pour caractériser les propriétés hydrauliques et hydrogéochimiques de l'aquifère de la craie dans des forages du Berkshire (Grande-Bretagne). Les mesures en descente ont été faites pour localiser les fissures dans la craie et leur développement spatial entre forages, et pour déterminer la qualité de l'eau souterraine des niveaux aquifères. Les méthodes géophysiques utilisées pour les diagraphies en forage étaient le calibrage, la résistivité concentrée, la résistivité par induction, le rayonnement gamma, la température du fluide, la conductivité électrique du fluide, un courantomètre à impulsions et à flux de chaleur, avec une sonde vidéo pour l'examen des parois du forage. Une sonde multiparamètre a été utilisée pour mesurer la température, la conductivité électrique, l'oxygène dissous, le pH et le potentiel redox dans le fluide du forage à la descente. Une forte perméabilité développée dans la craie par les écoulements souterrains forme le principal niveau d'écoulement du site d'étude de Banterwick Barn ; elle est constituée d'un système de conduits qui crée une connexion hydraulique locale efficace entre les forages. Cet horizon est formé de plusieurs niveaux de haut-fonds lithifiés, qui impliquent l'existence d'une lacune de sédimentation susceptible pouvant correspondre à une discordance. Une plus faible température de l'eau souterraine, une plus forte concentration en oxygène dissous, les indications du courantomètre sur un écoulement préférentiel dans la craie indiquent une circulation rapide de l'eau souterraine le long de cet horizon. En répétant les diagraphies à des moments différents de l'année sous des conditions hydrauliques variées, d'autres horizons d'écoulements d'eau dans l'aquifère de la craie ont été reconnus. Resumen. Se ha integrado técnicas geofísicas e hidroquímicas de registro de sondeos para caracterizar las propiedades hidráulicas e hidrogeoquímicas del acuífero de la Creta en perforaciones de Berkshire (Reino Unido). Las medidas en los sondeos tenían como objetivo localizar fisuras en las cretas, así como determinar su extensión espacial entre sondeos y calidad química de las aguas subterráneas. Entre los métodos de testificación geofísica utilizados, se halla el calibre, la resistividad focalizada e inducida, los rayos gamma, la temperatura y la conductividad eléctrica del fluido, impulsores y medidores de flujo en sondeos por pulsos de calor, junto con el televisor óptico en las paredes de los sondeos. Se ha empleado un transmisor multiparamétrico para medir la temperatura, la conductividad eléctrica, el oxígeno disuelto, el pH y el potencial redox de las aguas subterráneas en el sondeo. El horizonte más productivo está asociado a las superficies litificadas ('hardgrounds') de la Creta que han desarrollado una permeabilidad elevada debido a la circulación de las aguas subterráneas identificado en el emplazamiento de Banterwick Barn, representa un sistema de conductos que actúa como conexión hidráulica local efectiva entre los sondeos. La Creta incluye una serie de 'hardgrounds' compactada por migración de fluidos, produciendo un hiato sedimentario que posiblemente representa una inconformidad. La menor temperatura de las aguas subterráneas, junto con un alto contenido de oxígeno disuelto y la evidencia aportada por el medidor de flujo en sondeos respecto a un flujo preferente en la Creta, indican que la circulación de las aguas es rápida en dicho horizonte. Repitiendo la testificación en épocas distintas del año y bajo condiciones hidráulicas diferentes, se ha podido identificar otros niveles productivos en el acuífero de la Creta.

Recent progress in the growth and applications of graphene as a smart material: A review

NASA Astrophysics Data System (ADS)

Aissa, Brahim; Memon, Nasir; Ali, Adnan; Khraisheh, Marwan

2015-09-01

Innovative breakthroughs in fundamental research and industrial applications of graphene material have made its mass and low-cost production a necessary step toward its real world applications. This one-atom thick crystal of carbon, gathers a set of unique physico-chemical properties, ranging from its extreme mechanical behavior to its exceptional electrical and thermal conductivities, which are making graphene as a serious alternative to replace many conventional materials for various applications. In this review paper, we highlight the most important experimental results on the synthesis of graphene material, its emerging properties with reference to its smart applications. We discuss the possibility to successfully integrating graphene directly into device, enabling thereby the realization of a wide range of applications, including actuation, photovoltaic, thermoelectricity, shape memory, self-healing, electrorheology and space missions. The future outlook of graphene is also considered and discussed.

Reverse Electrorheological Effect:. a Suspension of Colloidal Motors

NASA Astrophysics Data System (ADS)

Lemaire, E.; Lobry, L.

We present an experimental evidence of a "colloidal motor" behavior of a suspension. Previous attempts to observe such a phenomenon with ferrofluids under alternating magnetic fields have failed. Here, negative viscosity is obtained by making use of Quincke rotation: the spontaneous rotation of insulating particles suspended in a weakly conducting liquid when the system is submitted to a DC electric field. In such a case, particles rotate around any axis perpendicular to the applied field, nevertheless, when a velocity gradient (simple shear rate) is applied along the E field direction, the particles rotation axes will be favored in the vorticity direction (the direction perpendicular to the suspension velocity and the velocity gradient). The collective movement of particles drives the surrounding liquid and then leads to a reduction of the apparent viscosity of the suspension. The decrease in viscosity is sufficiently important for the liquid to flow while no submitted to any mechanical stress.

Innovative model to simulate exhalation phase in human respiratory system.

PubMed

Sbrana, Tommaso; Landi, Alberto; Catapano, Giosuè Angelo

2011-11-01

In this paper, we present a mathematical model, which mimics the bronchial resistances of human's lung in an expiratory act. The model is implemented in Matlab. The inputs that are used in this model derive from spirometry test. This model is able to study a physiologic condition, a pathologic one and the patient's follow up after drug treatment. We split our study into two parts. The first one focuses the analysis on the gas fluido dynamic inside of the respiratory pathways. The second part takes care of the pressure equilibrium in the exchange zone. We use the outputs that derive from the second subsystem to solve the Bernoulli's equation of the first part. The model was validated with data provided from "Clinical Physiology Institute" of CNR and G. Monasterio Foundation of Pisa. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Development of Polythiophene/Acrylonitrile-Butadiene Rubbers for Artificial Muscle

NASA Astrophysics Data System (ADS)

Thipdech, Pacharavalee; Sirivat, Anuvat

2007-03-01

Electroactive polymers (EAPs) can respond to the applied electrical field by an extension or a retraction. In this work, we are interested in using an elastomeric blend for electroactive applications, acrylonitirle-butadiene rubber (NBR) containing a conductive polymer (Poly(3-thiopheneacetic acid, PTAA); the latter can be synthesized via oxidative polymerization. FT-IR, Thermogravimetric analysis (TGA), ^1H-NMR, UV-visible spectroscopy, and SEM are used to characterize the conductive polymer. Electrorheological properties are measured and investigated in terms of acrylonitrile content, blending ratio, doping level, and temperature. Experiments are carried out under oscillatory shear mode and with applied electric field strength varying from 0 to 2 kV/mm. Dielectric properties, conductivities are measured and correlated with the storage modulus responses. The storage modulus sensitivity, δG'G'0of the pure rubbers increases with increasing electric field strength. They attain the maximum values of about 30% and become constant at electric strength at and above 1000 V/mm.

Electrokinetic Particle Aggregation and Flow Instabilities in Non-Dilute Colloidal Suspensions

NASA Astrophysics Data System (ADS)

Navaneetham, Guru; Posner, Jonathan

2007-11-01

An experimental investigation of electrokinetic particle aggregation and flow instabilities of non-dilute colloidal suspensions in microfabricated channels is presented. The addition of charged colloidal particles can alter the solution's conductivity, permittivity as well as the average particle electrophoretic mobility. In this work, a colloid volume fraction gradient is achieved at the intersection of a Y-shaped PDMS microchannel. The solution conductivity and the particle mobility as a function of the particle (500 nm polystyrene) volume fraction are presented. The critical conditions required for particle aggregation and flow instability are given along with a scaling analysis which shows that the flow becomes unstable at a critical electric Rayleigh number for a wide range of applied electric fields and colloid volume fractions. Electrokinetic particle aggregation and instabilities of non-dilute colloidal suspensions may be important for applications such as the electrophoretic deposition of particles to form micropatterned colloidal assemblies, electrorheological devices, and on-chip, electrokinetic manipulation of colloids.

Electrically modulated capillary filling imbibition of nematic liquid crystals

NASA Astrophysics Data System (ADS)

Dhar, Jayabrata; Chakraborty, Suman

2018-04-01

The flow of nematic liquid crystals (NLCs) in the presence of an electric field is typically characterized by the variation in its rheological properties due to transition in its molecular arrangements. Here, we bring out a nontrivial interplay of a consequent alteration in the resistive viscous effects and driving electrocapillary interactions, toward maneuvering the capillary filling dynamics over miniaturized scales. Considering a dynamic interplay of the relevant bulk and interfacial forces acting in tandem, our results converge nicely to previously reported experimental data. Finally, we attempt a scaling analysis to bring forth further insight to the reported observations. Our analysis paves the way for the development of microfluidic strategies with previously unexplored paradigms of interaction between electrical and fluidic phenomenon, providing with an augmented controllability on capillary filling as compared to tthose reported to be achievable by the existing strategies. This, in turn, holds utilitarian scopes in improved designs of functional capillarities in electro-optical systems, electrorheological utilities, electrokinetic flow control, as well as in interfacing and imaging systems for biomedical microdevices.

Smart portable rehabilitation devices.

PubMed

Mavroidis, Constantinos; Nikitczuk, Jason; Weinberg, Brian; Danaher, Gil; Jensen, Katherine; Pelletier, Philip; Prugnarola, Jennifer; Stuart, Ryan; Arango, Roberto; Leahey, Matt; Pavone, Robert; Provo, Andrew; Yasevac, Dan

2005-07-12

The majority of current portable orthotic devices and rehabilitative braces provide stability, apply precise pressure, or help maintain alignment of the joints with out the capability for real time monitoring of the patient's motions and forces and without the ability for real time adjustments of the applied forces and motions. Improved technology has allowed for advancements where these devices can be designed to apply a form of tension to resist motion of the joint. These devices induce quicker recovery and are more effective at restoring proper biomechanics and improving muscle function. However, their shortcoming is in their inability to be adjusted in real-time, which is the most ideal form of a device for rehabilitation. This introduces a second class of devices beyond passive orthotics. It is comprised of "active" or powered devices, and although more complicated in design, they are definitely the most versatile. An active or powered orthotic, usually employs some type of actuator(s). In this paper we present several new advancements in the area of smart rehabilitation devices that have been developed by the Northeastern University Robotics and Mechatronics Laboratory. They are all compact, wearable and portable devices and boast re-programmable, real time computer controlled functions as the central theme behind their operation. The sensory information and computer control of the three described devices make for highly efficient and versatile systems that represent a whole new breed in wearable rehabilitation devices. Their applications range from active-assistive rehabilitation to resistance exercise and even have applications in gait training. The three devices described are: a transportable continuous passive motion elbow device, a wearable electro-rheological fluid based knee resistance device, and a wearable electrical stimulation and biofeedback knee device. Laboratory tests of the devices demonstrated that they were able to meet their design objectives. The prototypes of portable rehabilitation devices presented here did demonstrate that these concepts are capable of the performance their commercially available but non-portable counterparts exhibit. Smart, portable devices with the ability for real time monitoring and adjustment open a new era in rehabilitation where the recovery process could be dramatically improved.

Smart portable rehabilitation devices

PubMed Central

Mavroidis, Constantinos; Nikitczuk, Jason; Weinberg, Brian; Danaher, Gil; Jensen, Katherine; Pelletier, Philip; Prugnarola, Jennifer; Stuart, Ryan; Arango, Roberto; Leahey, Matt; Pavone, Robert; Provo, Andrew; Yasevac, Dan

2005-01-01

Background The majority of current portable orthotic devices and rehabilitative braces provide stability, apply precise pressure, or help maintain alignment of the joints with out the capability for real time monitoring of the patient's motions and forces and without the ability for real time adjustments of the applied forces and motions. Improved technology has allowed for advancements where these devices can be designed to apply a form of tension to resist motion of the joint. These devices induce quicker recovery and are more effective at restoring proper biomechanics and improving muscle function. However, their shortcoming is in their inability to be adjusted in real-time, which is the most ideal form of a device for rehabilitation. This introduces a second class of devices beyond passive orthotics. It is comprised of "active" or powered devices, and although more complicated in design, they are definitely the most versatile. An active or powered orthotic, usually employs some type of actuator(s). Methods In this paper we present several new advancements in the area of smart rehabilitation devices that have been developed by the Northeastern University Robotics and Mechatronics Laboratory. They are all compact, wearable and portable devices and boast re-programmable, real time computer controlled functions as the central theme behind their operation. The sensory information and computer control of the three described devices make for highly efficient and versatile systems that represent a whole new breed in wearable rehabilitation devices. Their applications range from active-assistive rehabilitation to resistance exercise and even have applications in gait training. The three devices described are: a transportable continuous passive motion elbow device, a wearable electro-rheological fluid based knee resistance device, and a wearable electrical stimulation and biofeedback knee device. Results Laboratory tests of the devices demonstrated that they were able to meet their design objectives. The prototypes of portable rehabilitation devices presented here did demonstrate that these concepts are capable of the performance their commercially available but non-portable counterparts exhibit. Conclusion Smart, portable devices with the ability for real time monitoring and adjustment open a new era in rehabilitation where the recovery process could be dramatically improved. PMID:16011801

The Pliocene Yafo Formation in Israel: Hydrogeologically inert or active?

NASA Astrophysics Data System (ADS)

Avisar, D.; Rosenthal, E.; Shulman, H.; Zilberbrand, M.; Flexer, A.; Kronfeld, J.; Ben Avraham, Z.; Fleischer, L.

For several decades the ``Saqiye beds'' (later renamed Yafo Formation) underlying the Coastal Plain aquifer (Kurkar Group) aquifer of Israel, were regarded as an extremely thick, tectonically undisturbed, and absolutely impervious aquiclude. Following intensive groundwater exploitation from the overlying Kurkar Group aquifer, brackish and saline waters were locally encountered in the lower parts of this aquifer and always at the contact with the underlying Yafo Formation aquiclude. The present study revealed that this aquiclude is not a uniform and impervious rock unit, but rather an alternation of pervious and impervious strata within the Yafo Formation containing highly pressured fluids of different - mostly high - salinities. The permeable beds are at an angular unconformity and in direct contact with the overlying Kurkar Group aquifer. The Yafo Formation and the underlying and overlying rock units are dislocated by numerous fault systems, which facilitate accessibility of brines into the Kurkar Group aquifer. The mobilization of the saline fluids and their injection into the Kurkar Group aquifer could be due either to diffusion of saline fluids occurring in the permeable horizons of the Petah Tiqva Member through the clays of the Yafo Formation or to their upconing following intensive pumping in the Coastal Plain aquifer. It could have also been caused by up-dip movement of saline water as the result of overpressure generated by major accumulation of gas in the permeable horizons. Another possible mechanism could be hydraulic contact with pressurized brines up-flowing along fault zones from deep-seated Jurassic or Cretaceous reservoirs. The squeezing of saline interstitial water from the clays of the Yafo Formation into the overlying Kurkar Group aquifer, is of secondary importance for groundwater salinization (its input is comparable with salt input from rain). Depuis longtemps, les «couches de Saqiye», nommées maintenant formation de Yafo, constituant le mur de l'aquifère côtier (série de Kurkar) d'Israël, ont été considérées comme un ensemble extrêmement épais, sans déformation tectonique et totalement imperméable. À la suite de l'exploitation intensive de l'eau souterraine de l'aquifère sus-jacent de la série de Kurkar, des eaux salées et des saumures sont rencontrées occasionnellement dans les parties les plus profondes de cet aquifère et toujours au contact de l'imperméable sous-jacent de la formation de Yafo. Cette étude a révélé que cet imperméable n'est pas une unité géologique uniforme et imperméable, mais qu'il s'agit plutôt d'une alternance de couches perméables et imperméables dans la formation de Yafo contenant des fluides sous des pressions fortes avec des salinités différentes (?) et en général élevées (?). Les niveaux perméables sont en discordance angulaire et en contact direct avec l'aquifère sus-jacent de la série de Kurkar. La formation de Yafo et les unités géologiques situées dessous et dessus sont disloquées par de nombreuses systèmes de failles, qui facilitent le passage des saumures dans l'aquifère de la série de Kurkar. La mobilisation des fluides salins et leur injection dans l'aquifère de Kurkar pourraient être dues soit à la diffusion des fluides salins dans les horizons perméables du Petah Tiqva au travers des argiles de la formation de Yafo, soit leur remontée par upconing sous l'effet de pompages intensifs dans l'aquifère de la plaine côtière. Il peut aussi être causé par la remontée des eaux salines selon le pendage sous l'effet d'une surpression provoquée par une accumulation considérable de gaz dans les horizons imperméables. Un autre mécanisme possible pourrait être un contact hydraulique avec des saumures sous pression, remontant le long des zones de faille depuis des réservoirs profonds jurassiques ou crétacés. L'expulsion d'eau saline interstitielle des argiles de la formation de Yafo dans l'aquifère de Kurkar est d'importance secondaire pour la salinisation de l'eau souterraine cet apport est comparable à celui de sels par les pluies. Durante décadas, las ``Saqiyebeds'' (rebautizadas como Formación Yafo) que se sitúan bajo el acuífero Costero (Grupo Kurkar) de Israel fueron consideradas como un acuicludo extremadamente potente, tectónicamente inalterado y totalmente impermeable. Como resultado de la explotación intensiva del Grupo Kurkar, se produjo la mezcla de aguas salobres y salinas en la zona inferior de dicho acuífero y siempre en el contacto con el acuicludo subyaciente de la Formación Yafo. Este estudio reveló que el acuicludo no es una unidad rocosa uniforme e impermeable, sino que consiste en una alternancia de estratos permeables e impermeables dentro de la Formación Yafo, que contiene fluidos a alta presión de salinidades diferentes pero generalmente elevadas. Las capas permeables se hallan en inconformidad angular y en contacto directo con el acuífero superior del Grupo Kurkar. La Formación Yafo y las unidades rocosas infra- y suprayacentes están dislocadas por numerosos sistemas de fallas, lo que facilita el acceso de las salmueras al acuífero del Grupo Kurkar. Los fluidos de los horizontes permeables del Miembro Petah Tiqva a través de las arcillas de la Formación Yafo o hacia el ascenso de los domos salinos en respuesta a la extracción intensiva en el acuífero del Llano Costero. Podría también haber sido causado por el movimiento a favor del buzamiento de las aguas salinas como resultado de la sobrepresión generada por una acumulación mayor de gas en los horizontes permeables. Otro posible mecanismo podría basarse en el contacto hidráulico con salmueras presurizadas, que fluyen hacia arriba a favor de zonas de falla desde los reservorios profundos del Jurásico o del Cretácico. La extracción de agua salina intersticial desde las arcillas de la Formación Yafo hacia el acuífero superior del Grupo Kurkar es de importancia secundaria para la salinización de las aguas subterráneas, ya que su aportación es comparable a la procedente del agua de lluvia.

Semi-active control of tracked vehicle suspension incorporating magnetorheological dampers

NASA Astrophysics Data System (ADS)

Ata, W. G.; Salem, A. M.

2017-05-01

In past years, the application of magnetorheological (MR) and electrorheological dampers in vehicle suspension has been widely studied, mainly for the purpose of vibration control. This paper presents theoretical study to identify an appropriate semi-active control method for MR-tracked vehicle suspension. Three representative control algorithms are simulated including the skyhook, hybrid and fuzzy-hybrid controllers. A seven degrees-of-freedom tracked vehicle suspension model incorporating MR dampers has been adopted for comparison between the performance of the three controllers. The model differential equations are derived based on Newton's second law of motion and the proposed control methods are developed. The performance of each control method under bump and sinusoidal road profiles for different vehicle speeds is simulated and compared with the performance of the conventional suspension system in time and frequency domains. The results show that the performance of tracked vehicle suspension with MR dampers is substantially improved. Moreover, the fuzzy-hybrid controller offers an excellent integrated performance in reducing the body accelerations as well as wheel bounce responses compared with the classical skyhook and hybrid controllers.

Simulaciones hidrodinámicas de flujos complejos

NASA Astrophysics Data System (ADS)

María Ibáñez Cabanell, José

Son muchos los escenarios astrofísicos en que los procesos hidrodinámicos juegan un papel clave. En la complejidad que encierra la descripción de dichos procesos destaca el de la correcta simulación de flujos complejos donde la presencia de ondas de choque fuertes que, eventualmente, interaccionan entre ellas o también la presencia de inestabilidades (Kelvin-Helmholtz, Rayleigh-Taylor, etc.) suponen un verdadero desafío numérico. Los códigos hidrodinámicos basados en la solución de un problema de valores iniciales discontinuo (problema de Riemann) son, en la actualidad, los más robustos en el campo de la dinámica de fluidos computacional. En esta charla se dará un resumen de los fundamentos de dichas técnicas numéricas (esquemas de alta resolución de captura de choques) y se ilustrará su potencialidad mostrando una amplia gama de resultados en diferentes aplicaciones astrofísicas.

Design of electro-active polymer gels as actuator materials

NASA Astrophysics Data System (ADS)

Popovic, Suzana

Smart materials, alternatively called active or adaptive, differ from passive materials in their sensing and activation capability. These materials can sense changes in environment such as: electric field, magnetic field, UV light, pH, temperature. They are capable of responding in numerous ways. Some change their stiffness properties (electro-rheological fluids), other deform (piezos, shape memory alloys, electrostrictive materials) or change optic properties (electrochromic polymers). Polymer gels are one of such materials which can change the shape, volume and even optical properties upon different applied stimuli. Due to their low stiffness property they are capable of having up to 100% of strain in a short time, order of seconds. Their motion resembles the one of biosystems, and they are often seen as possible artificial muscle materials. Despite their delicate nature, appropriate design can make them being used as actuator materials which can form controllable surfaces and mechanical switches. In this study several different groups of polymer gel material were investigated: (a) acrylamide based gels are sensitive to pH and electric field and respond in volume change, (b) polyacrylonitrile (PAN) gel is sensitive to pH and electric field and responds in axial strain and bending, (c) polyvinylalcohol (PVA) gel is sensitive to electric field and responds in axial strain and bending and (d) perfluorinated sulfonic acid membrane, Nafion RTM, is sensitive to electric field and responds in bending. Electro-mechanical and chemo-mechanical behavior of these materials is a function of a variety of phenomena: polymer structure, affinity of polymer to the solvent, charge distribution within material, type of solvent, elasticity of polymer matrix, etc. Modeling of this behavior is a task aimed to identify what is driving mechanism for activation and express it in a quantitative way in terms of deformation of material. In this work behavior of the most promising material as an actuator material, Nafion 117, was simulated. It was suggested that dominant phenomenon causing the material deformation is non-uniform water distribution within a material, that causes it to expand on one side and shrink on the other, macroscopically inducing bending of membrane. Uneven distribution of water is believed to be under the influence of two processes, electroosmosis and self-diffusion of free water.

Summary of semi-initiative and initiative control automobile engine vibration

NASA Astrophysics Data System (ADS)

Qu, Wei; Qu, Zhou

2009-07-01

Engine vibration accounts for around 55% of automobile vibration, separating the engine vibration from transmitting to automobile to the utmost extent is significant for improving NVH performance. Semi-initiative and initiative control of engine vibration is one of the hot spots of technical research in domestic and foreign automobile industry, especially luxury automobiles which adopt this technology to improve amenity and competitiveness. This article refers to a large amount of domestic and foreign related materials, fully introduces the research status of semi-initiative and initiative control suspension of engine vibration suspension and many kinds of structural style, and provides control policy and method of semi-initiative and initiative control suspension system. Compare and analyze the structural style of semi-initiative and initiative control and merits and demerits of current structures of semi-initiative and initiative control of mechanic electrorheological, magnetorheological, electromagnetic actuator, piezoelectric ceramics, electrostriction material, pneumatic actuator etc. Models of power assembly mounting system was classified.Calculation example indicated that reasonable selection of engine mounting system parameters is useful to reduce engine vibration transmission and to increase ride comfort. Finally we brought forward semi-initiative and initiative suspension which might be applied for automobiles, and which has a promising future.

Synchrotron X-ray Scattering from Self-organized Soft Nanostructures in Clays

NASA Astrophysics Data System (ADS)

Fossum, J. O.

2009-04-01

In the general context of self-organization of nanoparticles (in our case clay particles), and transitions in such structures, we study interconnected universal complex physical phenomena such as: (i) spontaneous gravitationally induced phase separation and nematic self-organization in systems of anisotropic clay nanoparticles in aqueous suspension, including studies of isotropic to nematic transitions [1,2] (ii) transitions from biaxial to uniaxial nematics by application of external magnetic field to self-organized systems of the same anisotropic (diamagnetic) clay nanoparticle systems [3,4] (iii) guided self-organization into chainlike structures of the same anisotropic clay nanoparticles in oil suspension when subjected to external electrical fields (electrorheological structures of polarized nanoparticles), and the stability of, and transitions of, such structures, when subjected to external mechanical stress [5,6] The experimental techniques used by us include synchrotron X-ray scattering, neutron scattering, rheometry. microscopy and magnetic resonance. We have demonstrated that clays may be used as good model systems for studies of universal physical phenomena and transitions in self-organized nanostructured soft and complex matter. Self-organization and related transitions in clay systems in particular, may have practical relevance for nano-patterning, properties of nanocomposites, and macroscopically anisotropic gels, among many other applications [7]. The synchrotron experiments have been performed at LNLS-Brazil, PLS- Korea, BNL-USA and ESRF-France. Acknowledgments: Collaborators, postdocs and students at NTNU-Norway, UiO-Norway, IFE-Norway, BNL-USA, LNLS-Brazil, UFPE-Brazil, UnB-Brazil, Univ. Amsterdam-Netherlands, Univ.Paris 7-France and other places. This research has been supported by the Research Council of Norway (RCN), through the NANOMAT, SUP and FRINAT Programs. References 1. J.O. Fossum, E. Gudding, D.d.M. Fonseca, Y. Meheust, E. DiMasi, T. Gog, C. Venkataraman, Observations of orientational ordering in aqueous suspensions of a nano-layered silicate, ENERGY The International Journal 30, 873 (2005). 2. D. M. Fonseca, Y. Méheust, J. O. Fossum, K. D. Knudsen, K. J. Måløy and K. P. S. Parmar, Phase behavior of platelet-shaped nanosilicate colloids in saline solutions: A small-angle X-ray scattering study J. Appl. Cryst. 40 292 (2007) 3. E. N. de Azevedo, M. Engelsberg, J. O. Fossum, R. E. de Souza, Anisotropic water diffusion in nematic self-assemblies of clay nano-platelets suspended in water, Langmuir 23, 5100 (2007) 4. Nils Ivar Ringdal, Master thesis, Department of Physics, NTNU (2008) 5. J.O. Fossum, Y. Meheust, K.P.S. Parmar, K.D. Knudsen, K.J. Maloy, D.d.M. Fonseca, Intercalation-enhanced electric polarization and chain formation of nano-layered particles, Europhys. Lett., 74, 438 (2006), and in the Scientific Highlights 2006 of the European Synchrotron Radiation Facility - ESRF (2007) 6. K.P.S. Parmar, Y. Meheust, B. Schelderupsen and J.O. Fossum, Electrorheological suspensions of laponite in oil: rheometry studies, Langmuir 24,1814 (2008) 7. F. Bergaya, B. K. G. Theng, and G. Lagaly, editors. Handbook of Clay Science. Elsevier (2006)

Complex (dusty) plasmas-kinetic studies of strong coupling phenomena

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

Morfill, Gregor E.; Ivlev, Alexei V.; Thomas, Hubertus M.

2012-05-15

'Dusty plasmas' can be found almost everywhere-in the interstellar medium, in star and planet formation, in the solar system in the Earth's atmosphere, and in the laboratory. In astrophysical plasmas, the dust component accounts for only about 1% of the mass, nevertheless this component has a profound influence on the thermodynamics, the chemistry, and the dynamics. Important physical processes are charging, sputtering, cooling, light absorption, and radiation pressure, connecting electromagnetic forces to gravity. Surface chemistry is another important aspect. In the laboratory, there is great interest in industrial processes (e.g., etching, vapor deposition) and-at the fundamental level-in the physics ofmore » strong coupling phenomena. Here, the dust (or microparticles) are the dominant component of the multi-species plasma. The particles can be observed in real time and space, individually resolved at all relevant length and time scales. This provides an unprecedented means for studying self-organisation processes in many-particle systems, including the onset of cooperative phenomena. Due to the comparatively large mass of the microparticles (10{sup -12}to10{sup -9}g), precision experiments are performed on the ISS. The following topics will be discussed: Phase transitions, phase separation, electrorheology, flow phenomena including the onset of turbulence at the kinetic level.« less

A new neuro-fuzzy training algorithm for identifying dynamic characteristics of smart dampers

NASA Astrophysics Data System (ADS)

Dzung Nguyen, Sy; Choi, Seung-Bok

2012-08-01

This paper proposes a new algorithm, named establishing neuro-fuzzy system (ENFS), to identify dynamic characteristics of smart dampers such as magnetorheological (MR) and electrorheological (ER) dampers. In the ENFS, data clustering is performed based on the proposed algorithm named partitioning data space (PDS). Firstly, the PDS builds data clusters in joint input-output data space with appropriate constraints. The role of these constraints is to create reasonable data distribution in clusters. The ENFS then uses these clusters to perform the following tasks. Firstly, the fuzzy sets expressing characteristics of data clusters are established. The structure of the fuzzy sets is adjusted to be suitable for features of the data set. Secondly, an appropriate structure of neuro-fuzzy (NF) expressed by an optimal number of labeled data clusters and the fuzzy-set groups is determined. After the ENFS is introduced, its effectiveness is evaluated by a prediction-error-comparative work between the proposed method and some other methods in identifying numerical data sets such as ‘daily data of stock A’, or in identifying a function. The ENFS is then applied to identify damping force characteristics of the smart dampers. In order to evaluate the effectiveness of the ENFS in identifying the damping forces of the smart dampers, the prediction errors are presented by comparing with experimental results.

Mechanics of pressure-adaptive honeycomb and its application to wing morphing

NASA Astrophysics Data System (ADS)

Vos, Roelof; Barrett, Ron

2011-09-01

Current, highly active classes of adaptive materials have been considered for use in many different aerospace applications. From adaptive flight control surfaces to wing surfaces, shape-memory alloy (SMA), piezoelectric and electrorheological fluids are making their way into wings, stabilizers and rotor blades. Despite the benefits which can be seen in many classes of aircraft, some profound challenges are ever present, including low power and energy density, high power consumption, high development and installation costs and outright programmatic blockages due to a lack of a materials certification database on FAR 23/25 and 27/29 certified aircraft. Three years ago, a class of adaptive structure was developed to skirt these daunting challenges. This pressure-adaptive honeycomb (PAH) is capable of extremely high performance and is FAA/EASA certifiable because it employs well characterized materials arranged in ways that lend a high level of adaptivity to the structure. This study is centered on laying out the mechanics, analytical models and experimental test data describing this new form of adaptive material. A directionally biased PAH system using an external (spring) force acting on the PAH bending structure was examined. The paper discusses the mechanics of pressure adaptive honeycomb and describes a simple reduced order model that can be used to simplify the geometric model in a finite element environment. The model assumes that a variable stiffness honeycomb results in an overall deformation of the honeycomb. Strains in excess of 50% can be generated through this mechanism without encountering local material (yield) limits. It was also shown that the energy density of pressure-adaptive honeycomb is akin to that of shape-memory alloy, while exhibiting strains that are an order of magnitude greater with an energy efficiency close to 100%. Excellent correlation between theory and experiment is demonstrated in a number of tests. A proof-of-concept wing section test was conducted on a 12% thick wing section representative of a modern commercial aircraft winglet or flight control surface with a 35% PAH trailing edge. It was shown that camber variations in excess of 5% can be generated by a pressure differential of 40 kPa. Results of subsequent wind tunnel test show an increase in lift coefficient of 0.3 at 23 m s - 1 through an angle of attack from - 6° to + 20°. This paper was originally presented at the 2010 ASME SMASIS conference, as paper 'SMASIS 2010-3634'. Despite the substantial changes that have been made to the paper, there are still various figures and text stemming from the original.

The future of stochastic and upscaling methods in hydrogeology

NASA Astrophysics Data System (ADS)

Nœtinger, Benoît; Artus, Vincent; Zargar, Ghassem

2005-03-01

Geological formations are complex features resulting from geological, mechanical, and physico-chemical processes occurring over a very wide range of length scales and time scales. Transport phenomena ranging from the molecular scale to several hundreds of kilometers may influence the overall behavior of fluid flow in these formations. Heterogeneities that cover a large range of spatial scales play an essential role to channel fluid-flows, especially when they are coupled with non-linearities inherent to transport processes in porous media. These issues have considerable practical importance in groundwater management, and in the oil industry, particularly in solving new problems posed by projects concerned with the trapping of CO2 in the subsurface. In order to manage this complexity, one must be able to prioritize the respective influences of various relevant geological and physico-chemical phenomena occurring at several ranges of length and time scales as well as understand and use the increasingly rich and complex geostatistical models to provide realistic simulations of subsurface conditions. Multiscale simulation of fluid transport in these formations should help engineers to focus on the crucial phenomena that control the flow. This provides a natural framework to integrate data, to solve inverse problems involving large amounts of data, resulting in a reduction of the uncertainties of the subsurface description that must be evaluated. This allows in turn the making of more relevant practical decisions. In this paper, some perspectives on the development of upscaling approaches are presented, highlighting some recent multiscale concepts, discarding the fractured media case. Upscaling can be used as a useful framework to simultaneously manage scale-dependant problems, stochastic approaches and inverse problems. Actual and potential applications of upscaling to the elaboration of subsurface models constrained to observed data, and the management of uncertainties and sensitivity studies in a global multiscale framework is emphasized. In particular, upscaling can help in finding the parameters that control the overall behavior of the flow. Finally, upscaling approaches of non-linear transport equations appear as a new frontier in this area of research. Les formations géologiques sont des entités complexes résultant de processus géologiques, mécaniques et physico-chimiques, à de larges palettes d'échelles de temps et d'espace. Les phénomènes de transport, qui sont définis de l'échelle moléculaire à l'échelle pluri-kilométrique, peut influencer le comportement global des écoulements dans les formations. Les hétérogénéités qui recouvrent plusieurs échelles spatiales jouent un rôle essentiel pour les écoulements canaliser, et plus spécialement lorsque les écoulements sont couplés avec des non-linéarités inhérentes aux processus de transport dans les milieux poreux. Les problémes ont une importance pratique considérable sur la gestion de l'eau souterraine, et dans l'industrie du pétrole, et plus particulièrement pour la résolution de nouveaux problèmes po sés par les projets concernés par le piégeage du CO2 en subsurface. De manière à gérer cette complexité, il faut être capable de donner la priorité aux influences respectives des phénomènes géologiques et physico-chimiques utiles, intervenant à différentes échelles de temps et d'espace, et comprendre et utiliser les modèles géostatistiques, riches et complexes, permettant de se munir de simulations réalistes des conditions de sub-surface. Les simulations de l'écoulement à plusieurs échelles, dans ces formations, peuvent aider les ingénieurs à se focaliser sur les phénomènes cruciaux qui contrôlent l'écoulement. Ceci apporte un cadre de travail pour intégrer les données, résoudre les problèmes inverses impliquant une grande quantité de données, résultant en une réduction de l'incertitude de la description de la subsurface devant être évaluée. Ceci permet de prendre des décisions plus pertinentes et pratiques. Dans cet article, certaines perspectives sur le développement d'approches «upscaling» (changement d' échelle) sont présentées, mettant en lumière des concepts mutli-échelles récents, en mettant de côté le problème du milieu fracturé. L'upscalling peut être utilisé comme un cadre utile pour gérer simultanément les problèmes d'échelle de travail, les approches stochastiques et les problèmes inverses. Les applications effectives et potentielles de l'upscalling sont mis en lumière, dans l'élaboration de modèles de subsurface contraints aux données observées, et la gestion des incertitudes et des études de sensibilité dans un cadre multi-échelle global. L'upscaling peut, en particulier, aider à trouver les paramètres qui contrôlent le comportement global de l'écoulement. Finalement, les approches par upscaling des équations non-linéaires de transport apparaissent comme une nouvelle frontière dans cette aire de recherche. Las formaciones geológicas son entidades complejas que resultan de procesos geológicos, mecánicos, y físico-químicos que ocurren en un rango muy amplio de escalas espaciales y escalas temporales. Los procesos de transporte que varían de la escala molecular a varios cientos de kilómetros pueden influenciar el comportamiento global del flujo de fluido en estas formaciones. Las heterogeneidades que cubren un rango amplio de escalas espaciales juegan un papel esencial para canalizar flujos de fluidos, especialmente cuando están acoplados con no linealidades inherentes a procesos de transporte en medios porosos. Estos asuntos tienen importancia práctica considerable en la gestión de aguas subterráneas, y en la industria petrolera, particularmente en la solución de problemas nuevos ocasionados por proyectos relacionados con el entrampamiento de CO2 en el subsuelo. Para gestionar esta complejidad uno tiene que priorizar las influencias respectivas de varios fenómenos relevantes geológicos y físico-químicos que ocurren en varios rangos de escalas espaciales y escalas temporales así como entender y utilizar modelos geoestadísticos complejos y cada vez más acaudalados para aportar simulaciones realisticas de los condiciones del subsuelo. La simulación en escalas múltiples del transporte de fluidos en estas formaciones debería de ayudar a los ingenieros a enfocarse en fenómenos cruciales que controlan el flujo. Esto aporta un marco natural para integrar datos, resolver problemas inversos que involucran gran cantidad de datos, resultando en una reducción de las incertidumbres de la descripción del subsuelo que tiene que evaluarse. Esto permite a la vez tomar más decisiones practicas relevantes. En este artículo se presentan algunas perspectivas sobre el desarrollo de los enfoques de escala alta, resaltando algunos conceptos de escalas múltiples recientes, descartando el caso de medio fracturado. La escala alta puede utilizarse como un marco útil para manejar simultáneamente problemas dependientes de escala, enfoques estocásticos y problemas inversos. Se enfatiza las aplicaciones reales y potenciales de escala alta para la elaboración de modelos subsuperficiales confrontados con datos observados, y el manejo de incertidumbres y estudios de sensitividad en un marco global de escalas múltiples. En particular, la escala a lta puede ayudar a encontrar los parámetros que controlan el comportamiento global del flujo. Finalmente, los enfoques de escala alta de ecuaciones de transporte no lineal aparecen como una nueva frontera en esta área de la investigación.

Seismic Response Control Of Structures Using Semi-Active and Passive Variable Stiffness Devices

NASA Astrophysics Data System (ADS)

Salem, Mohamed M. A.

Controllable devices such as Magneto-Rheological Fluid Dampers, Electro-Rheological Dampers, and controllable friction devices have been studied extensively with limited implementation in real structures. Such devices have shown great potential in reducing seismic demands, either as smart base isolation systems, or as smart devices for multistory structures. Although variable stiffness devices can be used for seismic control of structures, the vast majority of research effort has been given to the control of damping. The primary focus of this dissertation is to evaluate the seismic control of structures using semi-active and passive variable stiffness characteristics. Smart base isolation systems employing variable stiffness devices have been studied, and two semi-active control strategies are proposed. The control algorithms were designed to reduce the superstructure and base accelerations of seismically isolated structures subject to near-fault and far-field ground motions. Computational simulations of the proposed control algorithms on the benchmark structure have shown that excessive base displacements associated with the near-fault ground motions may be better mitigated with the use of variable stiffness devices. However, the device properties must be controllable to produce a wide range of stiffness changes for an effective control of the base displacements. The potential of controllable stiffness devices in limiting the base displacement due to near-fault excitation without compromising the performance of conventionally isolated structures, is illustrated. The application of passive variable stiffness devices for seismic response mitigation of multistory structures is also investigated. A stiffening bracing system (SBS) is proposed to replace the conventional bracing systems of braced frames. An optimization process for the SBS parameters has been developed. The main objective of the design process is to maintain a uniform inter-story drift angle over the building's height, which in turn would evenly distribute the seismic demand over the building. This behavior is particularly essential so that any possible damage is not concentrated in a single story. Furthermore, the proposed design ensures that additional damping devices distributed over the building's height work efficiently with their maximum design capacity, leading to a cost efficient design. An integrated and comprehensive design procedure that can be readily adopted by the current seismic design codes is proposed. An equivalent lateral force distribution is developed that shows a good agreement with the response history analyses in terms of seismic performance and demand prediction. This lateral force pattern explicitly accounts for the higher mode effect, the dynamic characteristics of the structure, the supplemental damping, and the site specific seismic hazard. Therefore, the proposed design procedure is considered as a standalone method for the design of SBS equipped buildings.

Regulación del flujo sanguíneo uterino. II. Funciones de estrógeno y receptores estrogénicos α/β en acciones genómicas y no-genómicas del endotelio uterino *

PubMed Central

Mayra, Pastore R.; Rosalina, Villalón L.; López, Gladys; Iruretagoyena, Jesús; Magness, Ronald

2015-01-01

Resumen El embarazo está marcado por cambios y adaptaciones cardiovasculares que son importantes para el crecimiento y mantenimiento de la placenta y el feto. Durante este periodo, las adaptaciones vasculares uterinas manifiestan cambios clasificados como de corto o largo plazo los cuales están relacionados con adaptaciones vasodilatadoras, angiogénicas o de remodelación. El estrógeno y los receptores estrogénicos clásicos (REs), RE-α y RE-β, han demostrado ser parcialmente responsables por facilitar el incremento dramático en el fluido sanguíneo uterino necesario durante el embarazo. En ésta revisión bibliográfica se discuten la base estructural para la diversidad y selectividad funcional de los REs por el estrógeno, el papel de los REs sobre los efectos genómicos y no-genómicos en células endoteliales de arterias uterinas (CEAU). Estos temas integran el conocimiento científico sobre la regulación molecular de CEAU para mantener el incremento fisiológico en la perfusión útero-placentaria observada durante un embarazo normal. PMID:26113751

Tectono-Magmatic Cycles and Geodynamic Settings of Ore-Bearing System Formation in the Southern Cis-Argun Region

NASA Astrophysics Data System (ADS)

Petrov, V. A.; Andreeva, O. V.; Poluektov, V. V.; Kovalenko, D. V.

2017-11-01

The ore-bearing geological structural units of the southern Cis-Argun region are considered in the context of varying geodynamic regimes related to the Proterozoic, Caledonian, and Hercynian tectono-magmatic cycles, as well as during the Late Mesozoic within-plate tectono-magmatic activity, which give rise to the formation of subalkaline igneous rocks of the Shakhtama Complex with Au, Cu-Mo, Pb-Zn-Ag metallogenic specialization; volcano-plutonic complexes of calderas with Mo-U, Pb-Zn, and fluorite ores; and rare-metal granite of the Kukulbei Complex with a Sn-W-Li-Ta spectrum of mineralization. The comparative geochemical characteristics inherent to Mesozoic ore-bearing felsic igneous rocks are considered, as well as geodynamic settings of ore-bearing fluido-magmatic systems, taking into consideration new data on geochemistry of bimodal trachybasalt-trachydacite series and rhyolite of the Turga Series, which fill the Strel'tsovka Caldera, whose trend of evolution is defined as a reference for geological history of the studied territory. The geodynamic conditions, phase composition, and geochemistry of rocks along with metallogenic specialization of Mesozoic volcano-plutonic complexes of southern Cis-Argun region are close to those of the Great Khingan Belt in northeastern China and eastern Mongolia.

A new fuzzy sliding mode controller for vibration control systems using integrated-structure smart dampers

NASA Astrophysics Data System (ADS)

Dzung Nguyen, Sy; Kim, Wanho; Park, Jhinha; Choi, Seung-Bok

2017-04-01

Vibration control systems using smart dampers (SmDs) such as magnetorheological and electrorheological dampers (MRD and ERD), which are classified as the integrated structure-SmD control systems (ISSmDCSs), have been actively researched and widely used. This work proposes a new controller for a class of ISSmDCSs in which high accuracy of SmD models as well as increment of control ability to deal with uncertainty and time delay are to be expected. In order to achieve this goal, two formualtion steps are required; a non-parametric SmD model based on an adaptive neuro-fuzzy inference system (ANFIS) and a novel fuzzy sliding mode controller (FSMC) which can weaken the model error of the ISSmDCSs and hence provide enhanced vibration control performances. As for the formulation of the proposed controller, first, an ANFIS controller is desgned to identify SmDs using the improved control algorithm named improved establishing neuro-fuzzy system (establishing neuro-fuzzy system). Second, a new control law for the FSMC is designed via Lyapunov stability analysis. An application to a semi-active MRD vehicle suspension system is then undertaken to illustrate and evaluate the effectiveness of the proposed control method. It is demonstrated through an experimental realization that the FSMC proposed in this work shows superior vibration control performance of the vehicle suspension compared to other surveyed controller which have similar structures to the FSMC, such as fuzzy logic and sliding mode control.

Comparative study of abdominal cavity temporary closure techniques for damage control.

PubMed

Ribeiro, Marcelo A F; Barros, Emily Alves; Carvalho, Sabrina Marques DE; Nascimento, Vinicius Pereira; Cruvinel, José; Fonseca, Alexandre Zanchenko

2016-01-01

The damage control surgery, with emphasis on laparostomy, usually results in shrinkage of the aponeurosis and loss of the ability to close the abdominal wall, leading to the formation of ventral incisional hernias. Currently, various techniques offer greater chances of closing the abdominal cavity with less tension. Thus, this study aims to evaluate three temporary closure techniques of the abdominal cavity: the Vacuum-Assisted Closure Therapy - VAC, the Bogotá Bag and the Vacuum-pack. We conducted a systematic review of the literature, selecting 28 articles published in the last 20 years. The techniques of the bag Bogotá and Vacuum-pack had the advantage of easy access to the material in most centers and low cost, contrary to VAC, which, besides presenting high cost, is not available in most hospitals. On the other hand, the VAC technique was more effective in reducing stress at the edges of lesions, removing stagnant fluids and waste, in addition to acting at the cellular level by increasing proliferation and cell division rates, and showed the highest rates of primary closure of the abdominal cavity. RESUMO A cirurgia de controle de danos, com ênfase em peritoneostomia, geralmente resulta em retração da aponeurose e perda da capacidade de fechar a parede abdominal, levando à formação de hérnias ventrais incisionais. Atualmente, várias técnicas oferecem maiores chances de fechamento da cavidade abdominal, com menor tensão. Deste modo, este estudo tem por objetivo avaliar três técnicas de fechamento temporário da cavidade abdominal: fechamento a vácuo (Vacuum-Assisted Closure Therapy - VAC), Bolsa de Bogotá e Vacuum-pack. Realizou-se uma revisão sistemática da literatura com seleção de 28 artigos publicados nos últimos 20 anos. As técnicas de Bolsa de Bogotá e Vacuum-pack tiveram como vantagem o acesso fácil ao material, na maioria dos centros, e baixo custo, ao contrário do que se observa na terapia a vácuo, VAC, que além de apresentar alto custo, não está disponível em grande parte dos hospitais. A técnica VAC, por outro lado, foi mais eficaz na redução da tensão nas bordas das lesões, ao remover fluidos estagnados e detritos, além de exercer ação a nível celular, aumentando as taxas de proliferação e divisão celular, e apresentou as maiores taxas de fechamento primário da cavidade abdominal.

Guided self-assembly of nanostructured titanium oxide

NASA Astrophysics Data System (ADS)

Wang, Baoxiang; Rozynek, Zbigniew; Fossum, Jon Otto; Knudsen, Kenneth D.; Yu, Yingda

2012-02-01

A series of nanostructured titanium oxide particles were synthesized by a simple wet chemical method and characterized by means of small-angle x-ray scattering (SAXS)/wide-angle x-ray scattering (WAXS), atomic force microscope (AFM), scanning electron microscope (SEM), transmission electron microscope (TEM), thermal analysis, and rheometry. Tetrabutyl titanate (TBT) and ethylene glycol (EG) can be combined to form either TiOx nanowires or smooth nanorods, and the molar ratio of TBT:EG determines which of these is obtained. Therefore, TiOx nanorods with a highly rough surface can be obtained by hydrolysis of TBT with the addition of cetyl-trimethyl-ammonium bromide (CTAB) as surfactant in an EG solution. Furthermore, TiOx nanorods with two sharp ends can be obtained by hydrolysis of TBT with the addition of salt (LiCl) in an EG solution. The AFM results show that the TiOx nanorods with rough surfaces are formed by the self-assembly of TiOx nanospheres. The electrorheological (ER) effect was investigated using a suspension of titanium oxide nanowires or nanorods dispersed in silicone oil. Oil suspensions of titanium oxide nanowires or nanorods exhibit a dramatic reorganization when submitted to a strong DC electric field and the particles aggregate to form chain-like structures along the direction of applied electric field. Two-dimensional SAXS images from chains of anisotropically shaped particles exhibit a marked asymmetry in the SAXS patterns, reflecting the preferential self-assembly of the particles in the field. The suspension of rough TiOx nanorods shows stronger ER properties than that of the other nanostructured TiOx particles. We find that the particle surface roughness plays an important role in modification of the dielectric properties and in the enhancement of the ER effect.

Guided self-assembly of nanostructured titanium oxide.

PubMed

Wang, Baoxiang; Rozynek, Zbigniew; Fossum, Jon Otto; Knudsen, Kenneth D; Yu, Yingda

2012-02-24

A series of nanostructured titanium oxide particles were synthesized by a simple wet chemical method and characterized by means of small-angle x-ray scattering (SAXS)/wide-angle x-ray scattering (WAXS), atomic force microscope (AFM), scanning electron microscope (SEM), transmission electron microscope (TEM), thermal analysis, and rheometry. Tetrabutyl titanate (TBT) and ethylene glycol (EG) can be combined to form either TiO(x) nanowires or smooth nanorods, and the molar ratio of TBT:EG determines which of these is obtained. Therefore, TiO(x) nanorods with a highly rough surface can be obtained by hydrolysis of TBT with the addition of cetyl-trimethyl-ammonium bromide (CTAB) as surfactant in an EG solution. Furthermore, TiO(x) nanorods with two sharp ends can be obtained by hydrolysis of TBT with the addition of salt (LiCl) in an EG solution. The AFM results show that the TiO(x) nanorods with rough surfaces are formed by the self-assembly of TiO(x) nanospheres. The electrorheological (ER) effect was investigated using a suspension of titanium oxide nanowires or nanorods dispersed in silicone oil. Oil suspensions of titanium oxide nanowires or nanorods exhibit a dramatic reorganization when submitted to a strong DC electric field and the particles aggregate to form chain-like structures along the direction of applied electric field. Two-dimensional SAXS images from chains of anisotropically shaped particles exhibit a marked asymmetry in the SAXS patterns, reflecting the preferential self-assembly of the particles in the field. The suspension of rough TiO(x) nanorods shows stronger ER properties than that of the other nanostructured TiO(x) particles. We find that the particle surface roughness plays an important role in modification of the dielectric properties and in the enhancement of the ER effect.

Generating Inviscid and Viscous Fluid Flow Simulations over a Surface Using a Quasi-simultaneous Technique

NASA Technical Reports Server (NTRS)

Sturdza, Peter (Inventor); Martins-Rivas, Herve (Inventor); Suzuki, Yoshifumi (Inventor)

2014-01-01

A fluid-flow simulation over a computer-generated surface is generated using a quasi-simultaneous technique. The simulation includes a fluid-flow mesh of inviscid and boundary-layer fluid cells. An initial fluid property for an inviscid fluid cell is determined using an inviscid fluid simulation that does not simulate fluid viscous effects. An initial boundary-layer fluid property a boundary-layer fluid cell is determined using the initial fluid property and a viscous fluid simulation that simulates fluid viscous effects. An updated boundary-layer fluid property is determined for the boundary-layer fluid cell using the initial fluid property, initial boundary-layer fluid property, and an interaction law. The interaction law approximates the inviscid fluid simulation using a matrix of aerodynamic influence coefficients computed using a two-dimensional surface panel technique and a fluid-property vector. An updated fluid property is determined for the inviscid fluid cell using the updated boundary-layer fluid property.

Generating Inviscid and Viscous Fluid-Flow Simulations over an Aircraft Surface Using a Fluid-Flow Mesh

NASA Technical Reports Server (NTRS)

Rodriguez, David L. (Inventor); Sturdza, Peter (Inventor)

2013-01-01

Fluid-flow simulation over a computer-generated aircraft surface is generated using inviscid and viscous simulations. A fluid-flow mesh of fluid cells is obtained. At least one inviscid fluid property for the fluid cells is determined using an inviscid fluid simulation that does not simulate fluid viscous effects. A set of intersecting fluid cells that intersects the aircraft surface are identified. One surface mesh polygon of the surface mesh is identified for each intersecting fluid cell. A boundary-layer prediction point for each identified surface mesh polygon is determined. At least one boundary-layer fluid property for each boundary-layer prediction point is determined using the at least one inviscid fluid property of the corresponding intersecting fluid cell and a boundary-layer simulation that simulates fluid viscous effects. At least one updated fluid property for at least one fluid cell is determined using the at least one boundary-layer fluid property and the inviscid fluid simulation.

An investigation of factors associated with fluid adherence among hemodialysis patients: a self-efficacy theory based approach.

PubMed

Brady, B A; Tucker, C M; Alfino, P A; Tarrant, D G; Finlayson, G C

1997-01-01

This research tested the hypothesis that fluid adherence (i.e. mean weekend interdialysis fluid weight gain) among adult chronic hemodialysis patients would have significant associations with fluid adherence efficacy expectation, fluid adherence outcome expectation, and fluid adherence motivation. The association of these variables with patients' medical characteristics was also examined. Results provide partial support for the hypothesis. Fluid adherence efficacy expectation was found to be a significant predictor of mean weekend interdialysis fluid weight gain (fluid adherence). Patients with higher fluid adherence efficacy expectations had lower mean weekend interdialysis fluid weight gains. However, fluid adherence outcome expectation and fluid adherence motivation were not found to be significant predictors of fluid adherence. Results also revealed that certain of the investigated medical characteristics were significantly associated with mean weekend interdialysis fluid weight gain and fluid adherence efficacy expectation. Implications for studying and modifying fluid adherence among hemodialysis patients are discussed.

Fluid imbalance

MedlinePlus

... up in the body. This is called fluid overload (volume overload). This can lead to edema (excess fluid in ... Water imbalance; Fluid imbalance - dehydration; Fluid buildup; Fluid overload; Volume overload; Loss of fluids; Edema - fluid imbalance; ...

Vínculos sobre um modelo de quartessência de Chaplygin usando observações do satélite chandra da fração de massa de gás em aglomerados de galáxias

NASA Astrophysics Data System (ADS)

de Souza, R. S.

2003-08-01

Observações de Supernovas do tipo Ia mostram que a expansão do Universo está acelerando. Segundo as equações de Einstein uma componente com pressão negativa (energia escura) é necessária para explicar a aceleração cósmica. Além da energia escura é usualmente admitido que no Universo há também uma matéria exótica com pressão zero, que é chamada de matéria escura. Essa componente possui um papel fundamental na formação de estruturas no Universo. Recentemente tem se explorado a possibilidade de que matéria e energia escura poderiam ser unificadas através de uma única componente, que tem sido denominada de quartessência. Um exemplo de fluido com essas características é o Gás de Chaplygin Generalizado, que possui uma equação de estado da forma p = -A/ra. Inicialmente consideramos o caso especial a = 1 (gás de Chaplygin) e vinculamos parâmetros do modelo utilizando observações em raios-X do satélite Chandra da fração de massa de gás em aglomerados de galáxias. Uma comparação dos vínculos obtidos com esse teste com outros testes, tais como supernovas e idade do Universo, mostra que esse teste é bastante restritivo. Exibiremos ainda resultados para o caso em que a curvatura é nula e o parâmetro a está compreendido no intervalo -1 < a 1.

Introduccion a la hidraulica de aguas subterraneas : un texto programado para auto-ensenanza

USGS Publications Warehouse

Bennett, Gordon D.

1987-01-01

Este ' texto programado esta diseflado para ayudarle a comprender la teoria de la hidniulica de aguas subterraneas por medio de la auto-enseflanza. La instrucci6n programada es un enfoque a una materia, un metodo de aprender;que no elimina el esfuerzo mental del proceso de aprendizaje. Algunas secciones de este programa necesitan solamente ser leidas; otras tendrian que ser elaboradas con lapiz y papel. Algunas preguntas pueden ser contestadas directamente; otras requieren calculos. A medida que se avanza en el texto, tendra que consultar frecuentemente textos o referencias sobre matematicas, mecanica de fluidos e hidrologia. En cada una de las ocho partes del texto, inicie el programa de instrucci6n leyendo la Secci6n 1. Elija una respuesta a la pregunta al final de la secci6n y dirijase a la nueva secci6n indicada al lado de la respuesta escogida. Si su respuesta fue correcta, pase a la secci6n que contiene materia nueva y otra pregunta, y proceda tal como en la Secci6n 1. Si su respuesta no fue correcta, dirijase a la secci6n que contiene explicaciones adicionales sobre el tema anterior y que le indica volver a la pregunta inicial e intentar de nuevo. En este caso, valdra Ia pena repasar el material de la secci6n anterior. Continue de esta man era en el programa hasta que llegue a Ia secci6n que indica el final de la parte. Observe que aunque las secciones estan en orden numerico en cada una de las ocho partes, por lo general, usted no procedeni en secuencia numerica (Secci6n 1 ala Secci6n 2, etc.) de principia a fin.

Multiple source/multiple target fluid transfer apparatus

DOEpatents

Turner, Terry D.

1997-01-01

A fluid transfer apparatus includes: a) a plurality of orifices for connection with fluid sources; b) a plurality of orifices for connection with fluid targets; c) a set of fluid source conduits and fluid target conduits associated with the orifices; d) a pump fluidically interposed between the source and target conduits to transfer fluid therebetween; e) a purge gas conduit in fluid communication with the fluid source conduits, fluid target conduits and pump to receive and pass a purge gas under pressure; f) a solvent conduit in fluid communication with the fluid source conduits, fluid target conduits and pump to receive and pass solvent, the solvent conduit including a solvent valve; g) pump control means for controlling operation of the pump; h) purge gas valve control means for controlling operation of the purge gas valve to selectively impart flow of purge gas to the fluid source conduits, fluid target conduits and pump; i) solvent valve control means for controlling operation of the solvent valve to selectively impart flow of solvent to the fluid source conduits, fluid target conduits and pump; and j) source and target valve control means for controlling operation of the fluid source conduit valves and the fluid target conduit valves to selectively impart passage of fluid between a selected one of the fluid source conduits and a selected one of the fluid target conduits through the pump and to enable passage of solvent or purge gas through selected fluid source conduits and selected fluid target conduits.

Multiple source/multiple target fluid transfer apparatus

DOEpatents

Turner, T.D.

1997-08-26

A fluid transfer apparatus includes: (a) a plurality of orifices for connection with fluid sources; (b) a plurality of orifices for connection with fluid targets; (c) a set of fluid source conduits and fluid target conduits associated with the orifices; (d) a pump fluidically interposed between the source and target conduits to transfer fluid there between; (e) a purge gas conduit in fluid communication with the fluid source conduits, fluid target conduits and pump to receive and pass a purge gas under pressure; (f) a solvent conduit in fluid communication with the fluid source conduits, fluid target conduits and pump to receive and pass solvent, the solvent conduit including a solvent valve; (g) pump control means for controlling operation of the pump; (h) purge gas valve control means for controlling operation of the purge gas valve to selectively impart flow of purge gas to the fluid source conduits, fluid target conduits and pump; (i) solvent valve control means for controlling operation of the solvent valve to selectively impart flow of solvent to the fluid source conduits, fluid target conduits and pump; and (j) source and target valve control means for controlling operation of the fluid source conduit valves and the fluid target conduit valves to selectively impart passage of fluid between a selected one of the fluid source conduits and a selected one of the fluid target conduits through the pump and to enable passage of solvent or purge gas through selected fluid source conduits and selected fluid target conduits. 6 figs.

Sys-BodyFluid: a systematical database for human body fluid proteome research

PubMed Central

Li, Su-Jun; Peng, Mao; Li, Hong; Liu, Bo-Shu; Wang, Chuan; Wu, Jia-Rui; Li, Yi-Xue; Zeng, Rong

2009-01-01

Recently, body fluids have widely become an important target for proteomic research and proteomic study has produced more and more body fluid related protein data. A database is needed to collect and analyze these proteome data. Thus, we developed this web-based body fluid proteome database Sys-BodyFluid. It contains eleven kinds of body fluid proteomes, including plasma/serum, urine, cerebrospinal fluid, saliva, bronchoalveolar lavage fluid, synovial fluid, nipple aspirate fluid, tear fluid, seminal fluid, human milk and amniotic fluid. Over 10 000 proteins are presented in the Sys-BodyFluid. Sys-BodyFluid provides the detailed protein annotations, including protein description, Gene Ontology, domain information, protein sequence and involved pathways. These proteome data can be retrieved by using protein name, protein accession number and sequence similarity. In addition, users can query between these different body fluids to get the different proteins identification information. Sys-BodyFluid database can facilitate the body fluid proteomics and disease proteomics research as a reference database. It is available at http://www.biosino.org/bodyfluid/. PMID:18978022

Sys-BodyFluid: a systematical database for human body fluid proteome research.

PubMed

Li, Su-Jun; Peng, Mao; Li, Hong; Liu, Bo-Shu; Wang, Chuan; Wu, Jia-Rui; Li, Yi-Xue; Zeng, Rong

2009-01-01

Recently, body fluids have widely become an important target for proteomic research and proteomic study has produced more and more body fluid related protein data. A database is needed to collect and analyze these proteome data. Thus, we developed this web-based body fluid proteome database Sys-BodyFluid. It contains eleven kinds of body fluid proteomes, including plasma/serum, urine, cerebrospinal fluid, saliva, bronchoalveolar lavage fluid, synovial fluid, nipple aspirate fluid, tear fluid, seminal fluid, human milk and amniotic fluid. Over 10,000 proteins are presented in the Sys-BodyFluid. Sys-BodyFluid provides the detailed protein annotations, including protein description, Gene Ontology, domain information, protein sequence and involved pathways. These proteome data can be retrieved by using protein name, protein accession number and sequence similarity. In addition, users can query between these different body fluids to get the different proteins identification information. Sys-BodyFluid database can facilitate the body fluid proteomics and disease proteomics research as a reference database. It is available at http://www.biosino.org/bodyfluid/.

Fluid channeling system

NASA Technical Reports Server (NTRS)

Davis, Donald Y. (Inventor); Hitch, Bradley D. (Inventor)

1994-01-01

A fluid channeling system includes a fluid ejector, a heat exchanger, and a fluid pump disposed in series flow communication The ejector includes a primary inlet for receiving a primary fluid, and a secondary inlet for receiving a secondary fluid which is mixed with the primary fluid and discharged therefrom as ejector discharge. Heat is removed from the ejector discharge in the heat exchanger, and the heat exchanger discharge is compressed in the fluid pump and channeled to the ejector secondary inlet as the secondary fluid In an exemplary embodiment, the temperature of the primary fluid is greater than the maximum operating temperature of a fluid motor powering the fluid pump using a portion of the ejector discharge, with the secondary fluid being mixed with the primary fluid so that the ejector discharge temperature is equal to about the maximum operating temperature of the fluid motor.

Systems and methods for separating particles and/or substances from a sample fluid

DOEpatents

Mariella, Jr., Raymond P.; Dougherty, George M.; Dzenitis, John M.; Miles, Robin R.; Clague, David S.

2016-11-01

Systems and methods for separating particles and/or toxins from a sample fluid. A method according to one embodiment comprises simultaneously passing a sample fluid and a buffer fluid through a chamber such that a fluidic interface is formed between the sample fluid and the buffer fluid as the fluids pass through the chamber, the sample fluid having particles of interest therein; applying a force to the fluids for urging the particles of interest to pass through the interface into the buffer fluid; and substantially separating the buffer fluid from the sample fluid.

System and method for filling a plurality of isolated vehicle fluid circuits through a common fluid fill port

DOEpatents

Sullivan, Scott C; Fansler, Douglas

2014-10-14

A vehicle having multiple isolated fluid circuits configured to be filled through a common fill port includes a first fluid circuit disposed within the vehicle, the first fluid circuit having a first fill port, a second fluid circuit disposed within the vehicle, and a conduit defining a fluid passageway between the first fluid circuit and second fluid circuit, the conduit including a valve. The valve is configured such that the first and second fluid circuits are fluidly coupled via the passageway when the valve is open, and are fluidly isolated when the valve is closed.

Acoustic concentration of particles in fluid flow

DOEpatents

Ward, Michael D.; Kaduchak, Gregory

2010-11-23

An apparatus for acoustic concentration of particles in a fluid flow includes a substantially acoustically transparent membrane and a vibration generator that define a fluid flow path therebetween. The fluid flow path is in fluid communication with a fluid source and a fluid outlet and the vibration generator is disposed adjacent the fluid flow path and is capable of producing an acoustic field in the fluid flow path. The acoustic field produces at least one pressure minima in the fluid flow path at a predetermined location within the fluid flow path and forces predetermined particles in the fluid flow path to the at least one pressure minima.

The effect of initial resident fluid saturation on the interaction between resident and infiltrating fluids in porous media

NASA Astrophysics Data System (ADS)

Hsu, S. Y.; Chen, H.; Huang, Q. Z.; Lee, T. Y.; Chiu, Y.; Chang, L. C.; Lamorski, K.; Sławiński, C.; Tsao, C. W.

2017-12-01

The interplay between resident ("old") fluid already in the vadose zone and infiltrating ("new") fluid was examined with micromodel experiments. The geometric patterns of the micromodels are based on a pore doublet and a 2D pore geometry of a sand-packing soil scanned by Micro X-Ray CT. We studied the old and new fluid interaction during imbibition process subject to different evaporation times (different the initial old fluid saturations). The results found that, in the pore-doublet micromodel experiment, the old fluid was mixed and displaced by the new fluid, and an increase in the initial old fluid saturation led to a decrease in the amount of old fluid displaced by the new fluid. On the other hand, the most of the old fluid in the micromodel of 2D sand-packing pore geometry was displaced by and mixed with the new fluid. However, a small amount of the initial old fluid that occupied pore throats remained untouched by the new fluid due to the air blockage. The amount of untouched old fluid increased as the initial old fluid saturation decreased. Our finding reveals the effect of pore geometry and inital old fluid distribution on the interaction between resident and infiltrating fluids.

Effect of pre-donation fluid intake on fluid shift from interstitial to intravascular compartment in blood donors.

PubMed

Deepika, Chenna; Murugesan, Mohandoss; Shastry, Shamee

2018-02-01

Fluid shifts from interstitial to intravascular space during blood donation helps in compensating the lost blood volume. We aimed to determine the volume of fluid shift following donation in donors with and without pre-donation fluid intake. We studied the fluid shift in 325 blood donors prospectively. Donors were divided in groups- with no fluid intake (GI) and either water (GII) or oral rehydrating fluids (GIII) before donation. Fluid shift following donation was calculated based on the difference between the pre and post donation blood volume. The influence of oral fluid intake, age, gender and body mass index (BMI) on volume of fluid shift was analyzed. The fluid shift was significant between donors without fluids (GI: 127 ± 81 ml) and donors with fluid intake (GII & III: 96 ± 45 ml) (p < 0.05). The difference was not significant between donors with water intake (GII: 106 ± 52 ml) and oral rehydrating fluid intake (GIII: 87 ± 41 ml). The shifted fluid volume increased with increasing BMI and decreased with increasing age in females. The fluid shift increased in females than in males. The age, gender, BMI and VVR did not significantly contribute to the volume of fluid shift following donation. As per our observation, the oral fluids before donation might not contribute to increase in fluid shift in blood donors after donation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Maintenance fluid therapy and fluid creep impose more significant fluid, sodium, and chloride burdens than resuscitation fluids in critically ill patients: a retrospective study in a tertiary mixed ICU population.

PubMed

Van Regenmortel, Niels; Verbrugghe, Walter; Roelant, Ella; Van den Wyngaert, Tim; Jorens, Philippe G

2018-04-01

Research on intravenous fluid therapy and its side effects, volume, sodium, and chloride overload, has focused almost exclusively on the resuscitation setting. We aimed to quantify all fluid sources in the ICU and assess fluid creep, the hidden and unintentional volume administered as a vehicle for medication or electrolytes. We precisely recorded the volume, sodium, and chloride burdens imposed by every fluid source administered to 14,654 patients during the cumulative 103,098 days they resided in our 45-bed tertiary ICU and simulated the impact of important strategic fluid choices on patients' chloride burdens. In septic patients, we assessed the impact of the different fluid sources on cumulative fluid balance, an established marker of morbidity. Maintenance and replacement fluids accounted for 24.7% of the mean daily total fluid volume, thereby far exceeding resuscitation fluids (6.5%) and were the most important sources of sodium and chloride. Fluid creep represented a striking 32.6% of the mean daily total fluid volume [median 645 mL (IQR 308-1039 mL)]. Chloride levels can be more effectively reduced by adopting a hypotonic maintenance strategy [a daily difference in chloride burden of 30.8 mmol (95% CI 30.5-31.1)] than a balanced resuscitation strategy [daily difference 3.0 mmol (95% CI 2.9-3.1)]. In septic patients, non-resuscitation fluids had a larger absolute impact on cumulative fluid balance than did resuscitation fluids. Inadvertent daily volume, sodium, and chloride loading should be avoided when prescribing maintenance fluids in view of the vast amounts of fluid creep. This is especially important when adopting an isotonic maintenance strategy.

CT findings of a unicameral calcaneal bone cyst containing a fluid-fluid level.

PubMed

Gallagher, Thomas A; Lim-Dunham, Jennifer E; Vade, Aruna

2007-03-01

Calcaneal unicameral bone cysts often contain fluid, but rarely contain fluid-fluid levels. We present a case focusing on the CT findings of a large calcaneal bone cyst with a fluid-fluid level and a review of the literature.

Segmented heat exchanger

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

Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron

2010-12-14

A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least amore » portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.« less

Pre-mixing apparatus for a turbine engine

DOEpatents

Lacy, Benjamin Paul [Greer, SC; Varatharajan, Balachandar [Cincinnati, OH; Ziminsky, Willy Steve [Simpsonville, SC; Kraemer, Gilbert Otto [Greer, SC; Yilmaz, Ertan [Albany, NY; Melton, Patrick Benedict [Horse Shoe, NC; Zuo, Baifang [Simpsonville, SC; Stevenson, Christian Xavier [Inman, SC; Felling, David Kenton [Greenville, SC; Uhm, Jong Ho [Simpsonville, SC

2012-04-03

A pre-mixing apparatus for a turbine engine includes a main body having an inlet portion, an outlet portion and an exterior wall that collectively establish at least one fluid delivery plenum, and a plurality of fluid delivery tubes extending through at least a portion of the at least one fluid delivery plenum. Each of the plurality of fluid delivery tubes includes at least one fluid delivery opening fluidly connected to the at least one fluid delivery plenum. With this arrangement, a first fluid is selectively delivered to the at least one fluid delivery plenum, passed through the at least one fluid delivery opening and mixed with a second fluid flowing through the plurality of fluid delivery tubes prior to being combusted in a combustion chamber of a turbine engine.

Insertable fluid flow passage bridgepiece and method

DOEpatents

Jones, Daniel O.

2000-01-01

A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.

Acoustic concentration of particles in fluid flow

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

Ward, Michael W.; Kaduchak, Gregory

Disclosed herein is a acoustic concentration of particles in a fluid flow that includes a substantially acoustically transparent membrane and a vibration generator that define a fluid flow path therebetween. The fluid flow path is in fluid communication with a fluid source and a fluid outlet and the vibration generator is disposed adjacent the fluid flow path and is capable of producing an acoustic field in the fluid flow path. The acoustic field produces at least one pressure minima in the fluid flow path at a predetermined location within the fluid flow path and forces predetermined particles in the fluidmore » flow path to the at least one pressure minima.« less

Heating production fluids in a wellbore

DOEpatents

Orrego, Yamila; Jankowski, Todd A.

2016-07-12

A method for heating a production fluid in a wellbore. The method can include heating, using a packer fluid, a working fluid flowing through a first medium disposed in a first section of the wellbore, where the first medium transfers heat from the packer fluid to the working fluid. The method can also include circulating the working fluid into a second section of the wellbore through a second medium, where the second medium transfers heat from the working fluid to the production fluid. The method can further include returning the working fluid to the first section of the wellbore through the first medium.

Method and apparatus for providing a precise amount of gas at a precise humidity

DOEpatents

Hallman, Jr., Russell L.; Truett, James C.

2001-02-06

A fluid transfer system includes a permeable fluid carrier, a constant temperature source of a first fluid, and a constant pressure source of a second fluid. The fluid carrier has a length, an inlet end, and an outlet end. The constant pressure source connects to the inlet end and communicates the second fluid into the fluid carrier, and the constant temperature source surrounds a least of portion of the length. A mixture of the first fluid and the second fluid exits via the outlet end A method of making a mixture of two fluids is also disclosed.

Gastric fluid versus amniotic fluid analysis for the identification of intra-amniotic infection due to Ureaplasma species

PubMed Central

Kim, Sun Min; Romero, Roberto; Lee, JoonHo; Chaemsaithong, Piya; Docheva, Nikolina; Yoon, Bo Hyun

2017-01-01

Objective Early neonatal sepsis is often due to intra-amniotic infection. The stomach of the neonate contains fluid swallowed before and during delivery. The presence of bacteria as well as neutrophils detected by culture or Gram stain in the gastric fluid during the first day of life is suggestive of exposure to bacteria or inflammation. We undertook this study to determine the relationship between gastric fluid analysis and amniotic fluid obtained by transabdominal amniocentesis in the detection of Ureaplasma species, the most frequent microorganisms responsible for intra-amniotic infection. Materials and Methods The study population consisted of 100 singleton pregnant women who delivered preterm neonates (<35weeks) within 7 days of amniocentesis. Gastric fluid of newborns was obtained by nasogastric intubation on the day of birth. Amniotic fluid and gastric fluid were cultured for genital Mycoplasmas and polymerase chain reaction (PCR) for Ureaplasma species was performed. Intra-amniotic inflammation was defined as an elevated amniotic fluid matrix metalloproteinase-8 concentration (> 23ng/mL). Results 1) Ureaplasma species were detected by culture or PCR in 18% (18/100) of amniotic fluid samples and in 5% (5/100) of gastric fluid samples; 2) among the amniotic fluid cases positive for Ureaplasma species, these microorganisms were identified in 27.8% (5/18) of gastric fluid samples; 3) none of the cases negative for Ureaplasma species in the amniotic fluid were found to be positive for these microorganisms in the gastric fluid; 4) patients with amniotic fluid positive for Ureaplasma species but with gastric fluid negative for these microorganisms had a significantly higher rate of intra-amniotic inflammation, acute histologic chorioamnionitis, and neonatal death than those with both amniotic fluid and gastric fluid negative for Ureaplasma species; and 5) no significant differences were observed in the rate of intra-amniotic inflammation, acute histologic chorioamnionitis, and neonatal death between patients with amniotic fluid positive for Ureaplasma species but with gastric fluid negative for these microorganisms and those with both amniotic fluid and gastric fluid positive for Ureaplasma species. Conclusions Gastric fluid analysis has 100% specificity in the identification of intra-amniotic infection with Ureaplasma species. However the detection of Ureaplasma species by culture or PCR in the gastric fluid of neonates at birth did not identify these microorganisms in two-thirds of cases with microbial invasion of the amniotic cavity. Thus, amniotic fluid analysis is superior to that of gastric fluid in the identification of intra-amniotic infection. PMID:26631980

Gastric fluid versus amniotic fluid analysis for the identification of intra-amniotic infection due to Ureaplasma species.

PubMed

Kim, Sun Min; Romero, Roberto; Lee, JoonHo; Chaemsaithong, Piya; Docheva, Nikolina; Yoon, Bo Hyun

2016-01-01

Early neonatal sepsis is often due to intra-amniotic infection. The stomach of the neonate contains fluid swallowed before and during delivery. The presence of bacteria as well as neutrophils detected by culture or Gram stain of the gastric fluid during the first day of life is suggestive of exposure to bacteria or inflammation. We undertook this study to determine the relationship between gastric fluid analysis and amniotic fluid obtained by transabdominal amniocentesis in the detection of Ureaplasma species, the most frequent microorganisms responsible for intra-amniotic infection. The study population consisted of 100 singleton pregnant women who delivered preterm neonates (<35 weeks) within 7 days of amniocentesis. Gastric fluid of newborns was obtained by nasogastric intubation on the day of birth. Amniotic fluid and gastric fluid were cultured for genital Mycoplasmas, and polymerase chain reaction (PCR) for Ureaplasma species was performed. Intra-amniotic inflammation was defined as an elevated amniotic fluid matrix metalloproteinase-8 concentration (>23 ng/mL). (1) Ureaplasma species were detected by culture or PCR in 18% (18/100) of amniotic fluid samples and in 5% (5/100) of gastric fluid samples; (2) among the amniotic fluid cases positive for Ureaplasma species, these microorganisms were identified in 27.8% (5/18) of gastric fluid samples; (3) none of the cases negative for Ureaplasma species in the amniotic fluid were found to be positive for these microorganisms in the gastric fluid; (4) patients with amniotic fluid positive for Ureaplasma species but with gastric fluid negative for these microorganisms had a significantly higher rate of intra-amniotic inflammation, acute histologic chorioamnionitis, and neonatal death than those with both amniotic fluid and gastric fluid negative for Ureaplasma species; and (5) no significant differences were observed in the rate of intra-amniotic inflammation, acute histologic chorioamnionitis, and neonatal death between patients with amniotic fluid positive for Ureaplasma species but with gastric fluid negative for these microorganisms and those with both amniotic fluid and gastric fluid positive for Ureaplasma species. Gastric fluid analysis has 100% specificity in the identification of intra-amniotic infection with Ureaplasma species. However, the detection of Ureaplasma species by culture or PCR in the gastric fluid of neonates at birth did not identify these microorganisms in two-thirds of cases with microbial invasion of the amniotic cavity. Thus, amniotic fluid analysis is superior to that of gastric fluid in the identification of intra-amniotic infection.

Hydrostatic bearings for a turbine fluid flow metering device

DOEpatents

Fincke, J.R.

1980-05-02

A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.

Encapsulated proppants

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

Aines, Roger D.; Bourcier, William L.; Duoss, Eric B.

2018-01-30

A capsule for carrying a proppant for emplaced in a formation containing formation fluid by a hydraulic fracture operation using a fracturing fluid. The capsule includes a capsule body. The capsule body includes a proppant. There is a surface layer on the capsule body that is permeable to the formation fluid or the fracturing fluid or is permeable to both the formation fluid and the fracturing fluid. The proppant material is dry cement that interacts with the formation fluid or the fracturing fluid or both the formation fluid and the fracturing fluid that migrate through the surface layer and ismore » taken up by the dry cement causing the dry cement to harden.« less

Encapsulated proppants

DOEpatents

Aines, Roger D.; Bourcier, William L.; Duoss, Eric B.; Roberts, Jeffery James; Spadaccini, Christopher M.; Stolaroff, Joshuah K.

2018-01-09

A capsule for carrying a proppant for emplaced in a formation containing formation fluid by a hydraulic fracture operation using a fracturing fluid. The capsule includes a capsule body. The capsule body includes a proppant. There is a surface layer on the capsule body that is permeable to the formation fluid or the fracturing fluid or is permeable to both the formation fluid and the fracturing fluid. The proppant material is dry cement that interacts with the formation fluid or the fracturing fluid or both the formation fluid and the fracturing fluid that migrate through the surface layer and is taken up by the dry cement causing the dry cement to harden.

Nanoscale wicking methods and devices

NASA Technical Reports Server (NTRS)

Zhou, Jijie (Inventor); Bronikowski, Michael (Inventor); Noca, Flavio (Inventor); Sansom, Elijah B. (Inventor)

2011-01-01

A fluid transport method and fluid transport device are disclosed. Nanoscale fibers disposed in a patterned configuration allow transport of a fluid in absence of an external power source. The device may include two or more fluid transport components having different fluid transport efficiencies. The components may be separated by additional fluid transport components, to control fluid flow.

Variable flexure-based fluid filter

DOEpatents

Brown, Steve B.; Colston, Jr., Billy W.; Marshall, Graham; Wolcott, Duane

2007-03-13

An apparatus and method for filtering particles from a fluid comprises a fluid inlet, a fluid outlet, a variable size passage between the fluid inlet and the fluid outlet, and means for adjusting the size of the variable size passage for filtering the particles from the fluid. An inlet fluid flow stream is introduced to a fixture with a variable size passage. The size of the variable size passage is set so that the fluid passes through the variable size passage but the particles do not pass through the variable size passage.

Reequilibration of fluid inclusions in low-temperature calcium-carbonate cement

NASA Astrophysics Data System (ADS)

Goldstein, Robert H.

1986-09-01

Calcium-carbonate cements precipitated in low-temperature, near-surface, vadose environments contain fluid inclusions of variable vapor-to-liquid ratios that yield variable homogenization temperatures. Cements precipitated in low-temperature, phreatic environments contain one-phase, all-liquid fluid inclusions. Neomorphism of unstable calcium-carbonate phases may cause reequilibration of fluid inclusions. Stable calcium-carbonate cements of low-temperature origin, which have been deeply buried, contain fluid inclusions of variable homogenization temperature and variable salt composition. Most inclusion fluids are not representative of the fluids present during cement growth and are more indicative of burial pore fluids. Therefore, low-temperature fluid inclusions probably reequilibrate with burial fluids during progressive burial. Reequilibration is likely caused by high internal pressures in inclusions which result in hydrofracturing. The resulting fluid-inclusion population could contain a nearly complete record of burial fluids in which a particular rock has been bathed. *Present address: Department of Geology, University of Kansas, Lawrence, Kansas 66045

Experimental and analytical study on fluid whirl and fluid whip modes

NASA Technical Reports Server (NTRS)

Muszynska, Agnes

1994-01-01

Fluid whirl and fluid whip are rotor self-excited, lateral vibrations which occur due to rotor interactions with the surrounding fluid. There exist various modes of fluid whirl and fluid whip. These modes are close to rotor modes corresponding to free vibrations (based on the linear model). Small differences are due to nonlinearities in the system. This paper presents experimental and analytical results on the lowest modes of fluid whirls and fluid whip. Examples of rotors supported in fluid lubricated bearings show the variations of rotor deflection amplitudes and phases in the whirl and whip modes with changes of rotative speeds and/or changes in lumped mass locations along the shaft.

Detection of contamination of municipal water distribution systems

DOEpatents

Cooper, John F [Oakland, CA

2012-01-17

A system for the detection of contaminates of a fluid in a conduit. The conduit is part of a fluid distribution system. A chemical or biological sensor array is connected to the conduit. The sensor array produces an acoustic signal burst in the fluid upon detection of contaminates in the fluid. A supervisory control system connected to the fluid and operatively connected to the fluid distribution system signals the fluid distribution system upon detection of contaminates in the fluid.

Space Station fluid management logistics

NASA Technical Reports Server (NTRS)

Dominick, Sam M.

1990-01-01

Viewgraphs and discussion on space station fluid management logistics are presented. Topics covered include: fluid management logistics - issues for Space Station Freedom evolution; current fluid logistics approach; evolution of Space Station Freedom fluid resupply; launch vehicle evolution; ELV logistics system approach; logistics carrier configuration; expendable fluid/propellant carrier description; fluid carrier design concept; logistics carrier orbital operations; carrier operations at space station; summary/status of orbital fluid transfer techniques; Soviet progress tanker system; and Soviet propellant resupply system observations.

Principles of fluid management and stewardship in septic shock: it is time to consider the four D's and the four phases of fluid therapy.

PubMed

Malbrain, Manu L N G; Van Regenmortel, Niels; Saugel, Bernd; De Tavernier, Brecht; Van Gaal, Pieter-Jan; Joannes-Boyau, Olivier; Teboul, Jean-Louis; Rice, Todd W; Mythen, Monty; Monnet, Xavier

2018-05-22

In patients with septic shock, the administration of fluids during initial hemodynamic resuscitation remains a major therapeutic challenge. We are faced with many open questions regarding the type, dose and timing of intravenous fluid administration. There are only four major indications for intravenous fluid administration: aside from resuscitation, intravenous fluids have many other uses including maintenance and replacement of total body water and electrolytes, as carriers for medications and for parenteral nutrition. In this paradigm-shifting review, we discuss different fluid management strategies including early adequate goal-directed fluid management, late conservative fluid management and late goal-directed fluid removal. In addition, we expand on the concept of the "four D's" of fluid therapy, namely drug, dosing, duration and de-escalation. During the treatment of patients with septic shock, four phases of fluid therapy should be considered in order to provide answers to four basic questions. These four phases are the resuscitation phase, the optimization phase, the stabilization phase and the evacuation phase. The four questions are "When to start intravenous fluids?", "When to stop intravenous fluids?", "When to start de-resuscitation or active fluid removal?" and finally "When to stop de-resuscitation?" In analogy to the way we handle antibiotics in critically ill patients, it is time for fluid stewardship.

Fluids and sepsis: changing the paradigm of fluid therapy: a case report.

PubMed

Hariyanto, Hori; Yahya, Corry Quando; Widiastuti, Monika; Wibowo, Primartanto; Tampubolon, Oloan Eduard

2017-02-04

Over the past 16 years, sepsis management has been guided by large-volume fluid administration to achieve certain hemodynamic optimization as advocated in the Rivers protocol. However, the safety of such practice has been questioned because large-volume fluid administration is associated with fluid overload and carries the worst outcome in patients with sepsis. Researchers in multiple studies have declared that using less fluid leads to increased survival, but they did not describe how to administer fluids in a timely and appropriate manner. An 86-year-old previously healthy Sundanese man was admitted to the intensive care unit at our institution with septic shock, acute kidney injury, and respiratory distress. Standard care was implemented during his initial care in the high-care unit; nevertheless, his condition worsened, and he was transferred to the intensive care unit. We describe the timing of fluid administration and elaborate on the amount of fluids needed using a conservative fluid regimen in a continuum of resuscitated sepsis. Because fluid depletion in septic shock is caused by capillary leak and pathologic vasoplegia, continuation of fluid administration will drive intravascular fluid into the interstitial space, thereby producing marked tissue edema and disrupting vital oxygenation. Thus, fluids have the power to heal or kill. Therefore, management of patients with sepsis should entail early vasopressors with adequate fluid resuscitation followed by a conservative fluid regimen.

Errors in fluid therapy in medical wards.

PubMed

Mousavi, Maryam; Khalili, Hossein; Dashti-Khavidaki, Simin

2012-04-01

Intravenous fluid therapy remains an essential part of patients' care during hospitalization. There are only few studies that focused on fluid therapy in the hospitalized patients, and there is not any consensus statement about fluid therapy in patients who are hospitalized in medical wards. The aim of the present study was to assess intravenous fluid therapy status and related errors in the patients during the course of hospitalization in the infectious diseases wards of a referral teaching hospital. This study was conducted in the infectious diseases wards of Imam Khomeini Complex Hospital, Tehran, Iran. During a retrospective study, data related to intravenous fluid therapy were collected by two clinical pharmacists of infectious diseases from 2008 to 2010. Intravenous fluid therapy information including indication, type, volume and rate of fluid administration was recorded for each patient. An internal protocol for intravenous fluid therapy was designed based on literature review and available recommendations. The data related to patients' fluid therapy were compared with this protocol. The fluid therapy was considered appropriate if it was compatible with the protocol regarding indication of intravenous fluid therapy, type, electrolyte content and rate of fluid administration. Any mistake in the selection of fluid type, content, volume and rate of administration was considered as intravenous fluid therapy errors. Five hundred and ninety-six of medication errors were detected during the study period in the patients. Overall rate of fluid therapy errors was 1.3 numbers per patient during hospitalization. Errors in the rate of fluid administration (29.8%), incorrect fluid volume calculation (26.5%) and incorrect type of fluid selection (24.6%) were the most common types of errors. The patients' male sex, old age, baseline renal diseases, diabetes co-morbidity, and hospitalization due to endocarditis, HIV infection and sepsis are predisposing factors for the occurrence of fluid therapy errors in the patients. Our result showed that intravenous fluid therapy errors occurred commonly in the hospitalized patients especially in the medical wards. Improvement in knowledge and attention of health-care workers about these errors are essential for preventing of medication errors in aspect of fluid therapy.

Hydrostatic bearings for a turbine fluid flow metering device

DOEpatents

Fincke, James R.

1982-01-01

A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.

Hydrostatic bearings for a turbine fluid flow metering device

DOEpatents

Fincke, J.R.

1982-05-04

A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion. 3 figs.

Effect of seven different additives on the properties of MR fluids

NASA Astrophysics Data System (ADS)

Zhang, J. Q.; Zhang, J.; Jing, Q.

2009-02-01

Magnetorheological (MR) fluids have been developed for application in semi-active magnetorheological fluid dampers and other magnetorheological fluid devices. In order to prepare special MR fluids to satisfy the demands of tracked vehicle, two different carrier fluids were chose to prepare MR fluids. Preparation of MR fluids, which are based on carriers such as special shock absorption fluid and 45# transformer oil, was finished. And characteristics of these samples were tested and analyzed. Results indicate, Tween-80 and Span-80 can improve sedimentary stability. Using 45# transformer oil instead of special shock absorption fluid as a carrier, the shear yield stress remains nearly invariable but the viscosity and the sedimentary stability are reduced. MR fluids with diameter of 2.73μm show better sedimentary stability than that of the MR fluids with diameter of 2.3μm, or 4.02μm. Stearic acid obviously improves sedimentary stability and off-state viscosity, but don't perform an obvious function on shear yield stress. In magnetic field of 237KA/m, the shear yield stress of MR fluid based on special shock absorption fluid and 45# transformer oil is 18.34KPa, 14.26KPa, respectively.

Apparatus for characterizing the temporo-spatial properties of a dynamic fluid front and method thereof

DOEpatents

Battiste, Richard L.

2007-12-25

Methods and apparatus are described for characterizing the temporal-spatial properties of a dynamic fluid front within a mold space while the mold space is being filled with fluid. A method includes providing a mold defining a mold space and having one or more openings into the mold space; heating a plurality of temperature sensors that extend into the mold space; injecting a fluid into the mold space through the openings, the fluid experiencing a dynamic fluid front while filling the mold space with the fluid; and characterizing temporal-spatial properties of the dynamic fluid front by monitoring a temperature of each of the plurality of heated temperature sensors while the mold space is being filled with the fluid. An apparatus includes a mold defining a mold space; one or more openings for introducing a fluid into the mold space and filling the mold space with the fluid, the fluid experiencing a dynamic fluid front while filling the mold space; a plurality of heated temperature sensors extending into the mold space; and a computer coupled to the plurality of heated temperature sensors for characterizing the temporal-spatial properties of the dynamic fluid front.

Apparatus for characterizing the temporo-spatial properties of a dynamic fluid front and method thereof

DOEpatents

Battiste, Richard L

2013-12-31

Methods and apparatus are described for characterizing the temporal-spatial properties of a dynamic fluid front within a mold space while the mold space is being filled with fluid. A method includes providing a mold defining a mold space and having one or more openings into the mold space; heating a plurality of temperature sensors that extend into the mold space; injecting a fluid into th emold space through the openings, the fluid experiencing a dynamic fluid front while filling the mold space with a fluid; and characterizing temporal-spatial properties of the dynamic fluid front by monitoring a termperature of each of the plurality of heated temperature sensors while the mold space is being filled with the fluid. An apparatus includes a mold defining a mold space; one or more openings for introducing a fluid into th emold space and filling the mold space with the fluid, the fluid experiencing a dynamic fluid front while filling the mold space; a plurality of heated temperature sensors extending into the mold space; and a computer coupled to the plurality of heated temperature sensors for characterizing the temporal-spatial properties of the dynamic fluid front.

Hydraulic engine valve actuation system including independent feedback control

DOEpatents

Marriott, Craig D

2013-06-04

A hydraulic valve actuation assembly may include a housing, a piston, a supply control valve, a closing control valve, and an opening control valve. The housing may define a first fluid chamber, a second fluid chamber, and a third fluid chamber. The piston may be axially secured to an engine valve and located within the first, second and third fluid chambers. The supply control valve may control a hydraulic fluid supply to the piston. The closing control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the second fluid chamber to the supply control valve. The opening control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the supply control valve to the second fluid chamber.

Fluid-loop reaction system

NASA Technical Reports Server (NTRS)

Lurie, Boris J. (Inventor); Schier, J. Alan (Inventor); Iskenderian, Theodore C. (Inventor)

1991-01-01

An improved fluid actuating system for imparting motion to a body such as a spacecraft is disclosed. The fluid actuating system consists of a fluid mass that may be controllably accelerated through at least one fluid path whereby an opposite acceleration is experienced by the spacecraft. For full control of the spacecraft's orientation, the system would include a plurality of fluid paths. The fluid paths may be circular or irregular, and the fluid paths may be located on the interior or exterior of the spacecraft.

Fluorescent fluid interface position sensor

DOEpatents

Weiss, Jonathan D.

2004-02-17

A new fluid interface position sensor has been developed, which is capable of optically determining the location of an interface between an upper fluid and a lower fluid, the upper fluid having a larger refractive index than a lower fluid. The sensor functions by measurement, of fluorescence excited by an optical pump beam which is confined within a fluorescent waveguide where that waveguide is in optical contact with the lower fluid, but escapes from the fluorescent waveguide where that waveguide is in optical contact with the upper fluid.

Blade for a gas turbine

DOEpatents

Liang, George

2010-10-26

A blade is provided for a gas turbine. The blade comprises a main body comprising a cooling fluid entrance channel; a cooling fluid collector in communication with the cooling fluid entrance channel; a plurality of side channels extending through an outer wall of the main body and communicating with the cooling fluid collector and a cooling fluid cavity; a cooling fluid exit channel communicating with the cooling fluid cavity; and a plurality of exit bores extending from the cooling fluid exit channel through the main body outer wall.

Thermal energy recycling fuel cell arrangement

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

Hanrahan, Paul R.

An example fuel cell arrangement includes a fuel cell stack configured to receive a supply fluid and to provide an exhaust fluid that has more thermal energy than the supply fluid. The arrangement also includes an ejector and a heat exchanger. The ejector is configured to direct at least some of the exhaust fluid into the supply fluid. The heat exchanger is configured to increase thermal energy in the supply fluid using at least some of the exhaust fluid that was not directed into the supply fluid.

Paleozoic fluid history of the Michigan Basin: Evidence from dolomite geochemistry in the Middle Ordovician St. Peter Sandstone

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

Winter, B.L.; Johnson, C.M.; Simo, J.A.

1995-04-03

The isotope (Sr and O) and elemental (Mg, Ca, Mn, Fe, and Sr) compositions of the various dolomites in the Middle Ordovician St. Peter Sandstone in the Michigan Basin are determined and the variations are modeled in terms of fluid-rock interaction or as mixing relations. These geochemical models, combined with the paragenetic sequence of the dolomites and late anhydrite cement, suggest the existence of at least four distinct diagenetic fluids in the St. Peter Sandstone during the paleozoic. Fluid 1 has a composition consistent with a modified older (pre-Middle Ordovician) seawater origin, which indicates that the flow path for thismore » fluid had a major upward component. This fluid resulted in the first and volumetrically most important burial dolomitization event, producing dolomite in both carbonate and quartz sandstone lithofacies in the St. Peter Sandstone. Fluid 2 has a composition consistent with a modified Middle to early Late Ordovician seawater origin, suggesting a major downward component for fluid flow. Fluid 2 produced dolomite cement in the carbonate lithofacies that postdates Fluid 1 dolomite. The composition of Fluid 3 is best interpreted to reflect a heated, deep basinal brine that had previously interacted with the K-feldspar-rich rocks near the Cambrian-Precambrian unconformity in the Michigan Basin, indicating a major upward component for fluid flow. Fluid 3 produced dolomite cement in quartz sandstone lithofacies that postdates Fluid 1 dolomite. Fluid 4 resulted in precipitation of late anhydrite in fractures. The {sup 87}Sr/{sup 86}Sr ratio of the anhydrite is consistent with Fluid 4 originating as a dilute fluid that interacted extensively with Silurian gypsum in the Michigan Basin; this indicates that the flow path of Fluid 4 had a major downward component.« less

A lattice Boltzmann investigation of steady-state fluid distribution, capillary pressure and relative permeability of a porous medium: Effects of fluid and geometrical properties

NASA Astrophysics Data System (ADS)

Li, Zi; Galindo-Torres, Sergio; Yan, Guanxi; Scheuermann, Alexander; Li, Ling

2018-06-01

Simulations of simultaneous steady-state two-phase flow in the capillary force-dominated regime were conducted using the state-of-the-art Shan-Chen multi-component lattice Boltzmann model (SCMC-LBM) based on two-dimensional porous media. We focused on analyzing the fluid distribution (i.e., WP fluid-solid, NP fluid-solid and fluid-fluid interfacial areas) as well as the capillary pressure versus saturation curve which was affected by fluid and geometrical properties (i.e., wettability, adhesive strength, pore size distribution and specific surface area). How these properties influenced the relative permeability versus saturation relation through apparent effective permeability and threshold pressure gradient was also explored. The SCMC-LBM simulations showed that, a thin WP fluid film formed around the solid surface due to the adhesive fluid-solid interaction, resulting in discrete WP fluid distributions and reduction of the WP fluid mobility. Also, the adhesive interaction provided another source of capillary pressure in addition to capillary force, which, however, did not affect the mobility of the NP fluid. The film fluid effect could be enhanced by large adhesive strength and fine pores in heterogeneous porous media. In the steady-state infiltration, not only the NP fluid but also the WP fluid were subjected to the capillary resistance. The capillary pressure effect could be alleviated by decreased wettability, large average pore radius and improved fluid connectivity in heterogeneous porous media. The present work based on the SCMC-LBM investigations elucidated the role of film fluid as well as capillary pressure in the two-phase flow system. The findings have implications for ways to improve the macroscopic flow equation based on balance of force for the steady-state infiltration.

Separation of supercritical slab-fluids to form aqueous fluid and melt components in subduction zone magmatism.

PubMed

Kawamoto, Tatsuhiko; Kanzaki, Masami; Mibe, Kenji; Matsukage, Kyoko N; Ono, Shigeaki

2012-11-13

Subduction-zone magmatism is triggered by the addition of H(2)O-rich slab-derived components: aqueous fluid, hydrous partial melts, or supercritical fluids from the subducting slab. Geochemical analyses of island arc basalts suggest two slab-derived signatures of a melt and a fluid. These two liquids unite to a supercritical fluid under pressure and temperature conditions beyond a critical endpoint. We ascertain critical endpoints between aqueous fluids and sediment or high-Mg andesite (HMA) melts located, respectively, at 83-km and 92-km depths by using an in situ observation technique. These depths are within the mantle wedge underlying volcanic fronts, which are formed 90 to 200 km above subducting slabs. These data suggest that sediment-derived supercritical fluids, which are fed to the mantle wedge from the subducting slab, react with mantle peridotite to form HMA supercritical fluids. Such HMA supercritical fluids separate into aqueous fluids and HMA melts at 92 km depth during ascent. The aqueous fluids are fluxed into the asthenospheric mantle to form arc basalts, which are locally associated with HMAs in hot subduction zones. The separated HMA melts retain their composition in limited equilibrium with the surrounding mantle. Alternatively, they equilibrate with the surrounding mantle and change the major element chemistry to basaltic composition. However, trace element signatures of sediment-derived supercritical fluids remain more in the melt-derived magma than in the fluid-induced magma, which inherits only fluid-mobile elements from the sediment-derived supercritical fluids. Separation of slab-derived supercritical fluids into melts and aqueous fluids can elucidate the two slab-derived components observed in subduction zone magma chemistry.

Separation of supercritical slab-fluids to form aqueous fluid and melt components in subduction zone magmatism

PubMed Central

Kawamoto, Tatsuhiko; Kanzaki, Masami; Mibe, Kenji; Ono, Shigeaki

2012-01-01

Subduction-zone magmatism is triggered by the addition of H2O-rich slab-derived components: aqueous fluid, hydrous partial melts, or supercritical fluids from the subducting slab. Geochemical analyses of island arc basalts suggest two slab-derived signatures of a melt and a fluid. These two liquids unite to a supercritical fluid under pressure and temperature conditions beyond a critical endpoint. We ascertain critical endpoints between aqueous fluids and sediment or high-Mg andesite (HMA) melts located, respectively, at 83-km and 92-km depths by using an in situ observation technique. These depths are within the mantle wedge underlying volcanic fronts, which are formed 90 to 200 km above subducting slabs. These data suggest that sediment-derived supercritical fluids, which are fed to the mantle wedge from the subducting slab, react with mantle peridotite to form HMA supercritical fluids. Such HMA supercritical fluids separate into aqueous fluids and HMA melts at 92 km depth during ascent. The aqueous fluids are fluxed into the asthenospheric mantle to form arc basalts, which are locally associated with HMAs in hot subduction zones. The separated HMA melts retain their composition in limited equilibrium with the surrounding mantle. Alternatively, they equilibrate with the surrounding mantle and change the major element chemistry to basaltic composition. However, trace element signatures of sediment-derived supercritical fluids remain more in the melt-derived magma than in the fluid-induced magma, which inherits only fluid-mobile elements from the sediment-derived supercritical fluids. Separation of slab-derived supercritical fluids into melts and aqueous fluids can elucidate the two slab-derived components observed in subduction zone magma chemistry. PMID:23112158

The partitioning of Fe, Ni, Cu, Pt, and Au between sulfide, metal, and fluid phases: A pilot study

NASA Astrophysics Data System (ADS)

Ballhaus, C.; Ryan, C. G.; Mernagh, T. P.; Green, D. H.

1994-01-01

This paper describes new experimental and analytical techniques to study element partitioning behavior between crystalline material and a late- to post-magmatic fluid phase. Samples of the fluid phase are isolated at experimental run conditions as synthetic fluid in quartz. Individual fluid inclusions are later analyzed for dissolved metals using Proton Induced X-ray Emission (PIXE). Back reactions between fluid and solid phases during quenching are prevented because the fluid is isolated at the experimental pressure, temperature ( P, T) conditions before quenching occurs. The technique is applied to study the partitioning of chalcophile elements (Fe, Ni, Cu, Pt and Au) between sulfide phases, metal alloys and supercritical SiO 2-NaCl-saturated H2O ± CH4- CO2- H2S fluids. Synthetic Ni-Cu-rich monosulfide solid solution (mss) doped with PtS or Au is packed in a quartz capsule and, together with a hydrogen buffer capsule and compounds to generate a fluid phase, welded shut in an outer Pt or Au metal capsule. The fluid phase is generated by combustion and reaction of various C-H-O fluid components during heating. Depending on capsule material and sample composition, the run products consist of platiniferous or auriferous mss, Pt-Fe, or ( Au, Cu) alloy phases, PtS, Fe 3O 4, sometimes a Cu-rich sulfide melt, and a fluid phase. Samples of the fluid are trapped in the walls of the quartz sample capsule as polyphase fluid inclusions. All phases are now available for analysis: fluid speciation is analyzed by piercing the outer metal capsule under vacuum and feeding the released fluid into a mass spectrometer. Phases and components within fluid inclusions are identified with Raman spectroscopy. Platinum and gold in solid solution in mss are determined with a CAMECA SX50 electron microanalyser. Metal contents trapped in selected fluid inclusions are determined quantitatively by in situ analysis with a proton microprobe using PIXE and a correction procedure specifically developed for quantitative fluid inclusion analysis. Initial results of metal solubilities in the fluid are as follows. Iron decreases from above 6,000 ppm under reduced conditions in the presence of H 2S in the fluid, to less than 1,000 ppm if hematite is stable in the crystalline run product. Copper and gold concentrations in the fluid range from about 600 to over 1200 and from 150 to about 270 ppm, respectively. The solubilities of these two metals in NaCl-saturated fluids are apparently independent of fluid speciations covered here. Nickel is mostly below detection limit (<10 ppm) and apparently poorly soluble in high-temperature fluid phases. Platinum concentrations in fluid inclusions are highly variable even among fluid inclusions of single runs, possibly because Pt tends to form multi-atom complexes in fluid phases.

Human body fluid proteome analysis

PubMed Central

Hu, Shen; Loo, Joseph A.; Wong, David T.

2010-01-01

The focus of this article is to review the recent advances in proteome analysis of human body fluids, including plasma/serum, urine, cerebrospinal fluid, saliva, bronchoalveolar lavage fluid, synovial fluid, nipple aspirate fluid, tear fluid, and amniotic fluid, as well as its applications to human disease biomarker discovery. We aim to summarize the proteomics technologies currently used for global identification and quantification of body fluid proteins, and elaborate the putative biomarkers discovered for a variety of human diseases through human body fluid proteome (HBFP) analysis. Some critical concerns and perspectives in this emerging field are also discussed. With the advances made in proteomics technologies, the impact of HBFP analysis in the search for clinically relevant disease biomarkers would be realized in the future. PMID:17083142

Human body fluid proteome analysis.

PubMed

Hu, Shen; Loo, Joseph A; Wong, David T

2006-12-01

The focus of this article is to review the recent advances in proteome analysis of human body fluids, including plasma/serum, urine, cerebrospinal fluid, saliva, bronchoalveolar lavage fluid, synovial fluid, nipple aspirate fluid, tear fluid, and amniotic fluid, as well as its applications to human disease biomarker discovery. We aim to summarize the proteomics technologies currently used for global identification and quantification of body fluid proteins, and elaborate the putative biomarkers discovered for a variety of human diseases through human body fluid proteome (HBFP) analysis. Some critical concerns and perspectives in this emerging field are also discussed. With the advances made in proteomics technologies, the impact of HBFP analysis in the search for clinically relevant disease biomarkers would be realized in the future.

Separation process using microchannel technology

DOEpatents

Tonkovich, Anna Lee [Dublin, OH; Perry, Steven T [Galloway, OH; Arora, Ravi [Dublin, OH; Qiu, Dongming [Bothell, WA; Lamont, Michael Jay [Hilliard, OH; Burwell, Deanna [Cleveland Heights, OH; Dritz, Terence Andrew [Worthington, OH; McDaniel, Jeffrey S [Columbus, OH; Rogers, Jr; William, A [Marysville, OH; Silva, Laura J [Dublin, OH; Weidert, Daniel J [Lewis Center, OH; Simmons, Wayne W [Dublin, OH; Chadwell, G Bradley [Reynoldsburg, OH

2009-03-24

The disclosed invention relates to a process and apparatus for separating a first fluid from a fluid mixture comprising the first fluid. The process comprises: (A) flowing the fluid mixture into a microchannel separator in contact with a sorption medium, the fluid mixture being maintained in the microchannel separator until at least part of the first fluid is sorbed by the sorption medium, removing non-sorbed parts of the fluid mixture from the microchannel separator; and (B) desorbing first fluid from the sorption medium and removing desorbed first fluid from the microchannel separator. The process and apparatus are suitable for separating nitrogen or methane from a fluid mixture comprising nitrogen and methane. The process and apparatus may be used for rejecting nitrogen in the upgrading of sub-quality methane.

Physically-Based Modelling and Real-Time Simulation of Fluids.

NASA Astrophysics Data System (ADS)

Chen, Jim Xiong

1995-01-01

Simulating physically realistic complex fluid behaviors presents an extremely challenging problem for computer graphics researchers. Such behaviors include the effects of driving boats through water, blending differently colored fluids, rain falling and flowing on a terrain, fluids interacting in a Distributed Interactive Simulation (DIS), etc. Such capabilities are useful in computer art, advertising, education, entertainment, and training. We present a new method for physically-based modeling and real-time simulation of fluids in computer graphics and dynamic virtual environments. By solving the 2D Navier -Stokes equations using a CFD method, we map the surface into 3D using the corresponding pressures in the fluid flow field. This achieves realistic real-time fluid surface behaviors by employing the physical governing laws of fluids but avoiding extensive 3D fluid dynamics computations. To complement the surface behaviors, we calculate fluid volume and external boundary changes separately to achieve full 3D general fluid flow. To simulate physical activities in a DIS, we introduce a mechanism which uses a uniform time scale proportional to the clock-time and variable time-slicing to synchronize physical models such as fluids in the networked environment. Our approach can simulate many different fluid behaviors by changing the internal or external boundary conditions. It can model different kinds of fluids by varying the Reynolds number. It can simulate objects moving or floating in fluids. It can also produce synchronized general fluid flows in a DIS. Our model can serve as a testbed to simulate many other fluid phenomena which have never been successfully modeled previously.

Lewis icing research tunnel test of the aerodynamic effects of aircraft ground deicing/anti-icing fluids

NASA Technical Reports Server (NTRS)

Runyan, L. James; Zierten, Thomas A.; Hill, Eugene G.; Addy, Harold E., Jr.

1992-01-01

A wind tunnel investigation of the effect of aircraft ground deicing/anti-icing fluids on the aerodynamic characteristics of a Boeing 737-200ADV airplane was conducted. The test was carried out in the NASA Lewis Icing Research Tunnel. Fluids tested include a Newtonian deicing fluid, three non-Newtonian anti-icing fluids commercially available during or before 1988, and eight new experimental non-Newtonian fluids developed by four fluid manufacturers. The results show that fluids remain on the wind after liftoff and cause a measurable lift loss and drag increase. These effects are dependent on the high-lift configuration and on the temperature. For a configuration with a high-lift leading-edge device, the fluid effect is largest at the maximum lift condition. The fluid aerodynamic effects are related to the magnitude of the fluid surface roughness, particularly in the first 30 percent chord. The experimental fluids show a significant reduction in aerodynamic effects.

Method and apparatus for producing drops using a drop-on-demand dispenser

DOEpatents

Chen, Alvin U.; Basaran, Osman A.

2003-01-01

A method and apparatus for dispensing fluid from a drop-on-demand (DOD) fluid dispenser. The method involves withdrawing fluid in the dispenser for a first duration of time, followed by a second duration of time during which the fluid is propelled toward the orifice of the dispenser. Following the period during which the fluid is propelled, there is a second withdrawing of the fluid into the dispenser. The duration of the propelling period is shorter than the duration of either the first withdrawing or the second withdrawing. The propelling of the fluid results in the extension of a small tongue of fluid from the meniscus of the fluid. The second withdrawing of the fluid results in a retraction of the meniscus into the passageway such that only the small tongue of fluid separates and is ejected from the dispenser.

Dual source heat pump

DOEpatents

Ecker, Amir L.; Pietsch, Joseph A.

1982-01-01

What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid provides energy for defrosting the second heat exchanger when operating in the air source mode and also provides a alternate source of heat.

Operation of a cascade air conditioning system with two-phase loop

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

Feng, Yinshan; Wang, Jinliang; Zhao, Futao

A method of operating a heat transfer system includes starting operation of a first heat transfer fluid vapor/compression circulation loop including a fluid pumping mechanism, a heat exchanger for rejecting thermal energy from a first heat transfer fluid, and a heat absorption side of an internal heat exchanger. A first conduit in a closed fluid circulation loop circulates the first heat transfer fluid therethrough. Operation of a second two-phase heat transfer fluid circulation loop is started after starting operation of the first heat transfer fluid circulation loop. The second heat transfer fluid circulation loop transfers heat to the first heatmore » transfer fluid circulation loop through the internal heat exchanger and includes a heat rejection side of the internal heat exchanger, a liquid pump, and a heat exchanger evaporator. A second conduit in a closed fluid circulation loop circulates a second heat transfer fluid therethrough.« less

Surface effects on friction-induced fluid heating in nanochannel flows.

PubMed

Li, Zhigang

2009-02-01

We investigate the mechanism of friction-induced fluid heating under the influence of surfaces. The temperature distributions of liquid argon and helium in nanoscale Poiseuille flows are studied through molecular dynamics simulations. It is found that the fluid heating is mainly caused by the viscous friction in the fluid when the external force is small and there is no slip at the fluid-solid interface. When the external force is larger than the fluid-surface binding force, the friction at the fluid-solid interface dominates over the internal friction of the fluid and is the major contribution to fluid heating. An asymmetric temperature gradient in the fluid is developed in the case of nonidentical walls and the general temperature gradient may change sign as the dominant heating factor changes from internal to interfacial friction with increasing external force. The effect of temperature on the fluid heating is also discussed.

7 CFR 1160.108 - Fluid milk processor.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk processor. 1160.108 Section 1160.108... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.108 Fluid milk processor. (a) Fluid milk processor means any person who...

7 CFR 1160.108 - Fluid milk processor.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk processor. 1160.108 Section 1160.108... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.108 Fluid milk processor. (a) Fluid milk processor means any person who...

7 CFR 1160.108 - Fluid milk processor.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk processor. 1160.108 Section 1160.108... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.108 Fluid milk processor. (a) Fluid milk processor means any person who...

7 CFR 1160.108 - Fluid milk processor.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk processor. 1160.108 Section 1160.108... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.108 Fluid milk processor. (a) Fluid milk processor means any person who...

7 CFR 1160.108 - Fluid milk processor.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk processor. 1160.108 Section 1160.108... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.108 Fluid milk processor. (a) Fluid milk processor means any person who...

Dynamic response of fluid inside a penny shaped crack

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

Hayashi, Kazuo; Seki, Hitoshi

1997-12-31

In order to discuss the method for estimating the geometric characteristics of geothermal reservoir cracks, a theoretical study is performed on the dynamic response of the fluid inside a reservoir crack in a rock mass subjected to a dynamic excitation due to propagation of an elastic wave. As representative models of reservoir cracks, a penny shaped crack and a two-dimensional crack which are connected to a borehole are considered. It is found that the resonance frequency of the fluid motion is dependent on the crack size, the fluid`s viscosity and the permeability of the formation. The intensity of the resonancemore » is dependent on the fluid`s viscosity when the size, the aperture and the permeability are fixed. It is also found that, at a value of the fluid`s viscosity, the resonance of fluid pressure becomes strongest. The optimum value of the fluid`s viscosity is found to be almost perfectly determined by the permeability of the formation. Furthermore, it is revealed that, if the fluid`s viscosity is fixed to be the optimum value, the resonance frequency is almost independent of the permeability and aperture, but is dependent on the size of crack. Inversely speaking, this implies that the size of the reservoir crack can be estimated from the resonance frequency, if the fluid with the above mentioned optimum value of viscosity is employed for hydraulic fracturing.« less

7 CFR 1160.107 - Fluid milk product.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk product. 1160.107 Section 1160.107... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.107 Fluid milk product. Fluid milk product means any product that meets the...

7 CFR 1160.107 - Fluid milk product.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk product. 1160.107 Section 1160.107... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.107 Fluid milk product. Fluid milk product means any product that meets the...

7 CFR 1160.107 - Fluid milk product.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk product. 1160.107 Section 1160.107... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.107 Fluid milk product. Fluid milk product means any product that meets the...

7 CFR 1160.107 - Fluid milk product.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk product. 1160.107 Section 1160.107... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.107 Fluid milk product. Fluid milk product means any product that meets the...

7 CFR 1160.107 - Fluid milk product.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk product. 1160.107 Section 1160.107... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.107 Fluid milk product. Fluid milk product means any product that meets the...

Performance of journal bearings with semi-compressible fluids

NASA Technical Reports Server (NTRS)

Carpino, M.; Peng, J.-P.

1991-01-01

Cryogenic fluids in isothermal rigid surface and foil type journal bearings can sometimes be treated as semicompressible fluids. In these applications, the fluid density is a function of the pressure. At low pressures, the fluids can change from a liquid to a saturated liquid-vapor phase. The performance of a rigid surface journal bearing with an idealized semicompressible fluid is discussed. Pressure solutions are based upon a Reynolds equation which includes the effects of a compressibility via the bulk modulus of the fluid. Results are contrasted with the performance of isothermal constant property incompressible fluids.

Time-Dependent Thermally-Driven Interfacial Flows in Multilayered Fluid Structures

NASA Technical Reports Server (NTRS)

Haj-Hariri, Hossein; Borhan, A.

1996-01-01

A computational study of thermally-driven convection in multilayered fluid structures will be performed to examine the effect of interactions among deformable fluid-fluid interfaces on the structure of time-dependent flow in these systems. Multilayered fluid structures in two models configurations will be considered: the differentially heated rectangular cavity with a free surface, and the encapsulated cylindrical liquid bridge. An extension of a numerical method developed as part of our recent NASA Fluid Physics grant will be used to account for finite deformations of fluid-fluid interfaces.

Enhanced Microfluidic Electromagnetic Measurements

NASA Technical Reports Server (NTRS)

Ricco, Antonio J. (Inventor); Kovacs, Gregory (Inventor); Giovangrandi, Laurent (Inventor)

2015-01-01

Techniques for enhanced microfluidic impedance spectroscopy include causing a core fluid to flow into a channel between two sheath flows of one or more sheath fluids different from the core fluid. Flow in the channel is laminar. A dielectric constant of a fluid constituting either sheath flow is much less than a dielectric constant of the core fluid. Electrical impedance is measured in the channel between at least a first pair of electrodes. In some embodiments, enhanced optical measurements include causing a core fluid to flow into a channel between two sheath flows of one or more sheath fluids different from the core fluid. An optical index of refraction of a fluid constituting either sheath flow is much less than an optical index of refraction of the core fluid. An optical property is measured in the channel.

[Fluid management and cause of death during shock period in patients with severe burns or burns complicated by inhalation injury].

PubMed

Zhang, Ming-liang; Li, Chi; Ma, Chun-xu

2003-11-01

To explore fluid management and cause of death during shock period in severe burns or burns with inhalation injury. One hundred and twelve patients with severe burns or burn complicated by inhalation injury admitted to our hospital from 1991 to 2000 were analyzed. The fluid management and death conditions during shock period were discussed. The fluid volume for resuscitation could be described as follows: the total fluid volume was 2.2 ml/(%TBSA.kg) including colloid fluid 0.5 ml/(%TBSA.kg), crystalloid fluid 1 ml/(%TBSA.kg)and water 0.7 ml/(%TBSA.kg) during first 24 hours. The total fluid volume was 1.8 ml/(%TBSA.kg) including colloid fluid 0.4 ml/(%TBSA.kg), crystalloid fluid 0.7 ml/(%TBSA.kg) and water 0.7 ml/(%TBSA.kg) during second 24 hours. There were no difference in fluid management between burns and burns with inhalation injury. Seven patients died due to respiratory failure during shock period. Many fluid formula can provide guidance for resuscitation and it is very important that early fluid therapy should accord with concrete clinical conditions of patients in order to pass smoothly through shock period. Early fluid management is not different between burns and burns with inhalation injury.

Partitioning of Large-ion Lithophile Elements Between Aqueous Fluids and Melts: Role of Saline Fluids in Sub-arc Mantle

NASA Astrophysics Data System (ADS)

Kawamoto, T.; Mibe, K.

2014-12-01

Chemical fractionation of slab-derived supercritical fluids can play an important role in elemental transfer from subducting slab to the mantle wedge and arc magmatism [1]. Recent findings of saline fluids from sub-arc mantle peridotite indicate that aqueous fluids in mantle wedge can contain 3.7 wt% NaCl in Ichinomageta, Northeast Japan arc [2] to 5.1 wt% NaCl in Pinatubo, Luzon arc [3]. It is, therefore, important to determine the effect of Cl on the trace element partitioning between aqueous fluids and melts. Synchrotron radiation X-ray fluorescence (XRF) analysis is conducted to know Rb, Sr, and Pb partitioning between aqueous fluids and melts [4]. There is a positive correlation between partition coefficients and pressure, as well as salinity. Two slab-derived components, melt and fluid components, are suggested to explain trace element characteristics of arc-basalts in the Mariana arc [5]. The fluid component is characterized by enrichment of alkali and alkali earth elements. Such features can be explained if the fluid component is a saline fluid, because alkali earth elements and Pb are much less mobile with Cl-free fluids than Cl-rich fluids [4]. We suggest that slab-derived components have compositional features consistent with a saline fluid and a melt, which can be formed through a separation of a slab-derived supercritical fluid [1]. Slab derived supercritical fluids contain Cl, and aqueous fluids inherit much of the Cl and some of the large-ion lithophile elements. [1] Kawamoto et al. 2012, Separation of supercritical slab-fluids to form aqueous fluid and melt components in subduction zone magmatism. PNAS, pnas.org/content/109/46/18695 [2] Kumagai et al. Evolution of carbon dioxide bearing saline fluids in the mantle wedge beneath the Northeast Japan arc, CMP [3] Kawamoto et al. 2013, Mantle wedge infiltrated with saline fluids from dehydration and decarbonation of subducting slab. PNAS, pnas.org/content/110/24/9663 [4] Kawamoto et al. 2014, Large ion lithophile elements delivered by saline fluids to the sub-arc mantle, EPS, earth-planets-space.com/content/66/1/61 [5] Pearce et al. 2005, Geochemical mapping of the Mariana arc-basin system: Implications for the nature and distribution of subduction components. G-cubed, onlinelibrary.wiley.com/doi/10.1029/2004GC000895/full

Hydrocarbon fluid, ejector refrigeration system

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

Kowalski, G.J.; Foster, A.R.

1993-08-31

A refrigeration system is described comprising: a vapor ejector cycle including a working fluid having a property such that entropy of the working fluid when in a saturated vapor state decreases as pressure decreases, the vapor ejector cycle comprising: a condenser located on a common fluid flow path; a diverter located downstream from the condenser for diverting the working fluid into a primary fluid flow path and a secondary fluid flow path parallel to the primary fluid flow path; an evaporator located on the secondary fluid flow path; an expansion device located on the secondary fluid flow path upstream ofmore » the evaporator; a boiler located on the primary fluid flow path parallel to the evaporator for boiling the working fluid, the boiler comprising an axially extending core region having a substantially constant cross sectional area and a porous capillary region surrounding the core region, the core region extending a length sufficient to produce a near sonic velocity saturated vapor; and an ejector having an outlet in fluid communication with the inlet of the condenser and an inlet in fluid communication with the outlet of the evaporator and the outlet of the boiler and in which the flows of the working fluid from the evaporator and the boiler are mixed and the pressure of the working fluid is increased to at least the pressure of the condenser, the ejector inlet, located downstream from the axially extending core region, including a primary nozzle located sufficiently close to the outlet of the boiler to minimize a pressure drop between the boiler and the primary nozzle, the primary nozzle of the ejector including a converging section having an included angle and length preselected to receive the working fluid from the boiler as a near sonic velocity saturated vapor.« less

Fail-fixed servovalve with positive fluid feedback

NASA Technical Reports Server (NTRS)

Kast, Howard B. (Inventor)

1984-01-01

The servovalve includes a primary jet of fluid. A variable control signal is adapted to vary the angular position of the primary jet from its maximum recovery position. A first fluid path is adapted to supply fluid to a servopiston at a variable pressure determined at least in part by the control signal. A second fluid path is adapted to receive a predetermined portion of the primary jet fluid when the control signal reaches a predetermined value. The second fluid path terminates in the vicinity of the primary jet and is adapted to direct a secondary jet of fluid at the primary jet to deflect the primary jet toward the input orifice of the second fluid path. The resultant positive fluid feedback in the second fluid path causes the primary jet to latch in a first angular position relative to the maximum recovery position when the control signal reaches a predetermined value. The servovalve may further include a means to discharge the fluid and a means to block the first fluid path to the servopiston when the control signal falls below a second predetermined value. A method of operating a fail-fixed servovalve is also described.

Capillary bending of a thin polymer film floating on a liquid bath

NASA Astrophysics Data System (ADS)

Twohig, Timothy; Croll, Andrew B.

Thin elastic films and shells are very important in schemes for the encapsulation and protection of fluids from their environment. Capillary origami is a particularly poignant example of how useful fluid/film structures can be formed. The interactions of fluids on thin-films which themselves lie on another surface (fluid or low friction solid) need to be studied if the differences from fluid-fluid and fluid-solid film interfaces are to be fully appreciated. In this experiment, we examine the triple line that occurs when a fluid is resting on a thin polymer film which is itself floating on a second fluid. The top fluid has a high-energy air/fluid interface which can be minimized by deforming the film in a manner that reduces the total air/fluid interface. We create a one-dimensional experiment in order to isolate the basic physics that occurs as the tension of the top fluid pulls on the thin film. Notably, the 1D geometry removes all the complexity incurred by thin films in biaxial stress states (such as wrinkling, folding and crumpling) from the problem. AFOSR under the Young Investigator Program (FA9550-15-1-0168).

Sublimation systems and associated methods

DOEpatents

Turner, Terry D.; McKellar, Michael G.; Wilding, Bruce M.

2016-02-09

A system for vaporizing and sublimating a slurry comprising a fluid including solid particles therein. The system includes a first heat exchanger configured to receive the fluid including solid particles and vaporize the fluid and a second heat exchanger configured to receive the vaporized fluid and solid particles and sublimate the solid particles. A method for vaporizing and sublimating a fluid including solid particles therein is also disclosed. The method includes feeding the fluid including solid particles to a first heat exchanger, vaporizing the fluid, feeding the vaporized fluid and solid particles to a second heat exchanger and sublimating the solid particles. In some embodiments the fluid including solid particles is liquid natural gas or methane including solid carbon dioxide particles.

Supercritical fluid reverse micelle separation

DOEpatents

Fulton, John L.; Smith, Richard D.

1993-01-01

A method of separating solute material from a polar fluid in a first polar fluid phase is provided. The method comprises combining a polar fluid, a second fluid that is a gas at standard temperature and pressure and has a critical density, and a surfactant. The solute material is dissolved in the polar fluid to define the first polar fluid phase. The combined polar and second fluids, surfactant, and solute material dissolved in the polar fluid is maintained under near critical or supercritical temperature and pressure conditions such that the density of the second fluid exceeds the critical density thereof. In this way, a reverse micelle system defining a reverse micelle solvent is formed which comprises a continuous phase in the second fluid and a plurality of reverse micelles dispersed in the continuous phase. The solute material is dissolved in the polar fluid and is in chemical equilibrium with the reverse micelles. The first polar fluid phase and the continuous phase are immiscible. The reverse micelles each comprise a dynamic aggregate of surfactant molecules surrounding a core of the polar fluid. The reverse micelle solvent has a polar fluid-to-surfactant molar ratio W, which can vary over a range having a maximum ratio W.sub.o that determines the maximum size of the reverse micelles. The maximum ratio W.sub.o of the reverse micelle solvent is then varied, and the solute material from the first polar fluid phase is transported into the reverse micelles in the continuous phase at an extraction efficiency determined by the critical or supercritical conditions.

Experimental Simulation of Shock Reequilibration of Fluid Inclusions During Meteorite Impact

NASA Technical Reports Server (NTRS)

Madden, M. E. Elwood; Hoerz, R. J.; Bodnar, R. J.

2003-01-01

Fluid inclusions are microscopic volumes of fluid trapped within minerals as they precipitate. Fluid inclusions are common in terrestrial minerals formed under a wide array of geological settings from surface evaporite deposits to kimberlite pipes. While fluid inclusions in terrestrial rocks are the rule rather than the exception, only few fluid inclusion-bearing meteorites have been documented. The rarity of fluid inclusions in meteoritic material may be explained in two ways. First, it may reflect the absence of fluids (water?) on meteorite parent bodies. Alternatively, fluids may have been present when the rock formed, but any fluid inclusions originally trapped on the parent body were destroyed by the extreme P-T conditions meteorites often experience during impact events. Distinguishing between these two possibilities can provide significant constraints on the likelihood of life on the parent body. Just as textures, structures, and compositions of mineral phases can be significantly altered by shock metamorphism upon hypervelocity impact, fluid inclusions contained within component minerals may be altered or destroyed due to the high pressures, temperatures, and strain rates associated with impact events. Reequilibration may occur when external pressure-temperature conditions differ significantly from internal fluid isochoric conditions, and result in changes in fluid inclusion properties and/or textures. Shock metamorphism and fluid inclusion reequilibration can affect both the impacted target material and the meteoritic projectile. By examining the effects of shock deformation on fluid inclusion properties and textures we may be able to better constrain the pressure-temperature path experienced by shocked materials and also gain a clearer understanding of why fluid inclusions are rarely found in meteoritic samples.

Supercritical fluid reverse micelle separation

DOEpatents

Fulton, J.L.; Smith, R.D.

1993-11-30

A method of separating solute material from a polar fluid in a first polar fluid phase is provided. The method comprises combining a polar fluid, a second fluid that is a gas at standard temperature and pressure and has a critical density, and a surfactant. The solute material is dissolved in the polar fluid to define the first polar fluid phase. The combined polar and second fluids, surfactant, and solute material dissolved in the polar fluid is maintained under near critical or supercritical temperature and pressure conditions such that the density of the second fluid exceeds the critical density thereof. In this way, a reverse micelle system defining a reverse micelle solvent is formed which comprises a continuous phase in the second fluid and a plurality of reverse micelles dispersed in the continuous phase. The solute material is dissolved in the polar fluid and is in chemical equilibrium with the reverse micelles. The first polar fluid phase and the continuous phase are immiscible. The reverse micelles each comprise a dynamic aggregate of surfactant molecules surrounding a core of the polar fluid. The reverse micelle solvent has a polar fluid-to-surfactant molar ratio W, which can vary over a range having a maximum ratio W[sub o] that determines the maximum size of the reverse micelles. The maximum ratio W[sub o] of the reverse micelle solvent is then varied, and the solute material from the first polar fluid phase is transported into the reverse micelles in the continuous phase at an extraction efficiency determined by the critical or supercritical conditions. 27 figures.

Freeform fluidics

DOEpatents

Dehoff, Ryan R; Lind, Randall F; Love, Lonnie L; Peter, William H; Richardson, Bradley S

2015-02-10

A robotic, prosthetic or orthotic member includes a body formed of a solidified metallic powder. At least one working fluid cylinder is formed in the body. A piston is provided in the working fluid cylinder for pressurizing a fluid in the cylinder. At least one working fluid conduit receives the pressurized fluid from the cylinder. The body, working fluid cylinder and working fluid conduit have a unitary construction. A method of making a robotic member is also disclosed.

Fluid technology (selected components, devices, and systems): A compilation

NASA Technical Reports Server (NTRS)

1974-01-01

Developments in fluid technology and hydraulic equipment are presented. The subjects considered are: (1) the use of fluids in the operation of switches, amplifiers, and servo devices, (2) devices and data for laboratory use in the study of fluid dynamics, and (3) the use of fluids as controls and certain methods of controlling fluids.

Spikes and matter inhomogeneities in massless scalar field models

NASA Astrophysics Data System (ADS)

Coley, A. A.; Lim, W. C.

2016-01-01

We shall discuss the general relativistic generation of spikes in a massless scalar field or stiff perfect fluid model. We first investigate orthogonally transitive (OT) G 2 stiff fluid spike models both heuristically and numerically, and give a new exact OT G 2 stiff fluid spike solution. We then present a new two-parameter family of non-OT G 2 stiff fluid spike solutions, obtained by the generalization of non-OT G 2 vacuum spike solutions to the stiff fluid case by applying Geroch's transformation on a Jacobs seed. The dynamics of these new stiff fluid spike solutions is qualitatively different from that of the vacuum spike solutions in that the matter (stiff fluid) feels the spike directly and the stiff fluid spike solution can end up with a permanent spike. We then derive the evolution equations of non-OT G 2 stiff fluid models, including a second perfect fluid, in full generality, and briefly discuss some of their qualitative properties and their potential numerical analysis. Finally, we discuss how a fluid, and especially a stiff fluid or massless scalar field, affects the physics of the generation of spikes.

Effect of an oxygen plasma on the physical and chemical properties of several fluids for the liquid droplet radiator

NASA Technical Reports Server (NTRS)

Gulino, D. A.; Coles, C. E.

1986-01-01

The Liquid Droplet Radiator is one of several radiator systems currently under investigation by NASA Lewis Research Center. It involves the direct exposure of the radiator working fluid to the space environment. An area of concern is the potential harmful effects of the low-Earth-orbit atomic oxygen environment on the radiator working fluid. To address this issue, seven candidate fluids were exposed to an oxygen plasma environment in a laboratory plasma asher. The fluids studied included Dow Corning 705 Diffusion Pump Fluid, polymethylphenylsiloxane and polydimethlsiloxane, both of which are experimental fluids made by Dow Corning, Fomblin Z25, made by Montedison, and three fluids from the Krytox family of fluids, Krytox 143AB, 1502, and 16256, which are made by DuPont. The fluids were characterized by noting changes in visual appearance, physical state, mass, and infrared spectra. Of the fluids tested, the Fomblin and the three Krytoxes were the least affected by the oxygen plasma. The only effect noted was a change in mass, which was most likely due to an oxygen-catalyzed deploymerization of the fluid molecule.

Shock Re-equilibration of Fluid Inclusions

NASA Technical Reports Server (NTRS)

Madden, M. E. Elwood; Horz, F.; Bodnar, R. J.

2004-01-01

Fluid inclusions (microscopic volumes of fluid trapped within minerals as they precipitate) are extremely common in terrestrial minerals formed under a wide range of geological conditions from surface evaporite deposits to kimberlite pipes. While fluid inclusions in terrestrial rocks are nearly ubiquitous, only a few fluid inclusion-bearing meteorites have been documented. The scarcity of fluid inclusions in meteoritic materials may be a result of (a) the absence of fluids when the mineral was formed on the meteorite parent body or (b) the destruction of fluid inclusions originally contained in meteoritic materials by subsequent shock metamorphism. However, the effects of impact events on pre-existing fluid inclusions trapped in target and projectile rocks has received little study. Fluid inclusions trapped prior to the shock event may be altered (re-equilibrated) or destroyed due to the high pressures, temperatures, and strain rates associated with impact events. By examining the effects of shock deformation on fluid inclusion properties and textures we may be able to better constrain the pressure-temperature path experienced by terrestrial and meteoritic shocked materials and also gain a clearer understanding of why fluid inclusions are rarely found in meteorite samples.

Heat pipe with dual working fluids

NASA Technical Reports Server (NTRS)

Shlosinger, A. P. (Inventor)

1973-01-01

A heat pipe design is offered that utilizes an auxiliary working fluid. The fluid, although being less efficient than the main working fluid, remains liquid at low heat loads when the main working fluid freezes.

Implementing a Loosely Coupled Fluid Structure Interaction Finite Element Model in PHASTA

NASA Astrophysics Data System (ADS)

Pope, David

Fluid Structure Interaction problems are an important multi-physics phenomenon in the design of aerospace vehicles and other engineering applications. A variety of computational fluid dynamics solvers capable of resolving the fluid dynamics exist. PHASTA is one such computational fluid dynamics solver. Enhancing the capability of PHASTA to resolve Fluid-Structure Interaction first requires implementing a structural dynamics solver. The implementation also requires a correction of the mesh used to solve the fluid equations to account for the deformation of the structure. This results in mesh motion and causes the need for an Arbitrary Lagrangian-Eulerian modification to the fluid dynamics equations currently implemented in PHASTA. With the implementation of both structural dynamics physics, mesh correction, and the Arbitrary Lagrangian-Eulerian modification of the fluid dynamics equations, PHASTA is made capable of solving Fluid-Structure Interaction problems.

Heat pump employing optimal refrigerant compressor for low pressure ratio applications

DOEpatents

Ecker, Amir L.

1982-01-01

What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler for circulating the fluid in heat exchange relationship with a refrigerant fluid; two refrigerant heat exchangers; one for effecting the heat exchange with the fluid and a second refrigerant-heat exchange fluid heat exchanger for effecting a low pressure ratio of compression of the refrigerant; a rotary compressor for compressing the refrigerant with low power consumption at the low pressure ratio; at least one throttling valve connecting at the inlet side of heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit serially connecting the above elements; refrigerant in the circuit; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant.

Early pleural fluid dynamics following video-assisted thoracoscopic lobectomy has limited clinical value

PubMed Central

Holbek, Bo Laksáfoss; Petersen, René Horsleben; Kehlet, Henrik

2017-01-01

The objective of this study was to evaluate the potential of predicting the pleural fluid output in patients after video-assisted thoracoscopic lobectomy of the lung. Detailed measurements of continuous fluid output were obtained prospectively using an electronic thoracic drainage device (Thopaz+™, Medela AG, Switzerland). Patients were divided into high (≥500 mL) and low (<500 mL) 24-hour fluid output, and detailed flow curves were plotted graphically to identify arithmetic patterns predicting fluid output in the early (≤24 hours) and later (24–48 hours) post-operative phase. Furthermore, multiple logistic regression analysis was used to predict high 24-hour fluid output using baseline data. Data were obtained from 50 patients, where 52% had a fluid output of <500 mL/24 hours. From visual assessment of flow curves, patients were grouped according to fluid output 6 hours postoperatively. An output ≥200 mL/6 hours was predictive of ‘high 24-hour fluid output’ (P<0.0001). However, 33% of patients with <200 mL/6 hours ended with a ‘high 24-hour fluid output’. Baseline data showed no predictive value of fluid production, and 24-hour fluid output had no predictive value of fluid output between 24 and 48 hours. Assessment of initial fluid production may predict high 24-hour fluid output (≥500 mL) but seems to lack clinical value in drain removal criteria. PMID:28840021

Heat exchange assembly

DOEpatents

Lowenstein, Andrew; Sibilia, Marc; Miller, Jeffrey; Tonon, Thomas S.

2004-06-08

A heat exchange assembly comprises a plurality of plates disposed in a spaced-apart arrangement, each of the plurality of plates includes a plurality of passages extending internally from a first end to a second end for directing flow of a heat transfer fluid in a first plane, a plurality of first end-piece members equaling the number of plates and a plurality of second end-piece members also equaling the number of plates, each of the first and second end-piece members including a recessed region adapted to fluidly connect and couple with the first and second ends of the plate, respectively, and further adapted to be affixed to respective adjacent first and second end-piece members in a stacked formation, and each of the first and second end-piece members further including at least one cavity for enabling entry of the heat transfer fluid into the plate, exit of the heat transfer fluid from the plate, or 180.degree. turning of the fluid within the plate to create a serpentine-like fluid flow path between points of entry and exit of the fluid, and at least two fluid conduits extending through the stacked plurality of first and second end-piece members for providing first fluid connections between the parallel fluid entry points of adjacent plates and a fluid supply inlet, and second fluid connections between the parallel fluid exit points of adjacent plates and a fluid discharge outlet so that the heat transfer fluid travels in parallel paths through each respective plate.

Hear Exchange Assembly

DOEpatents

Lowenstein, Andrew; Sibilia, Marc; Miller, Jeffrey; Tonon, Thomas S.

2003-05-27

A heat exchange assembly comprises a plurality of plates disposed in a spaced-apart arrangement, each of the plurality of plates includes a plurality of passages extending internally from a first end to a second end for directing flow of a heat transfer fluid in a first plane, a plurality of first end-piece members equaling the number of plates and a plurality of second end-piece members also equaling the number of plates, each of the first and second end-piece members including a recessed region adapted to fluidly connect and couple with the first and second ends of the plate, respectively, and further adapted to be affixed to respective adjacent first and second end-piece members in a stacked formation, and each of the first and second end-piece members further including at least one cavity for enabling entry of the heat transfer fluid into the plate, exit of the heat transfer fluid from the plate, or 180.degree. turning of the fluid within the plate to create a serpentine-like fluid flow path between points of entry and exit of the fluid, and at least two fluid conduits extending through the stacked plurality of first and second end-piece members for providing first fluid connections between the parallel fluid entry points of adjacent plates and a fluid supply inlet, and second fluid connections between the parallel fluid exit points of adjacent plates and a fluid discharge outlet so that the heat transfer fluid travels in parallel paths through each respective plate.

Sources, Fluxes, and Effects of Fluids in the Alpine Fault Zone, South Island, New Zealand

NASA Astrophysics Data System (ADS)

Menzies, C. D.; Teagle, D. A. H.; Niedermann, S.; Cox, S.; Craw, D.; Zimmer, M.; Cooper, M. J.; Erzinger, J.

2015-12-01

Historic ruptures on some plate boundary faults occur episodically. Fluids play a key role in modifying the chemical and physical properties of fault zones, which may prime them for repeated rupture by the generation of high pore fluid pressures. Modelling of fluid loss rates from fault zones has led to estimates of fluid fluxes required to maintain overpressure (Faulkner and Rutter, 2001), but fluid sources and fluxes, and permeability evolution in fault zones remain poorly constrained. High mountains in orogenic belts can drive meteoric water to the middle crust, and metamorphic water is generated during rock dehydration. Additionally, fluids from the mantle are transported into the crust when fluid pathways are created by tectonism or volcanism. Here we use geochemical tracers to determine fluid flow budgets for meteoric, metamorphic and mantle fluids at a major compressional tectonic plate boundary. The Alpine Fault marks the transpressional Pacific-Australian plate boundary through South Island of New Zealand, it has historically produced large earthquakes (Mw ~8) and is late in its 329±68 year seismic cycle, having last ruptured in 1717. We present strontium isotope ratios of hot springs and hydrothermal minerals that trace fluid flow paths in and around the Alpine Fault to illustrate that the fluid flow regime is restricted by low cross-fault permeability. Fluid-rock interaction limits cross-fault fluid flow by the precipitating clays and calcite that infill pore spaces and fractures in the Alpine Fault alteration zone. In contrast, helium isotopes ratios measured in hot springs near to the fault (0.15-0.81 RA) indicate the fault acts as a conduit for mantle fluids from below. Mantle fluid fluxes are similar to the San Andreas Fault (<1x10-5 m3m-2/yr) and insufficient to promote fault weakening. The metamorphic fluid flux is of similar magnitude to the mantle flux. The dominant fluid throughout the seismogenic zone is meteoric in origin (secondary mineral δDH2O = -45 to -87 ‰), but fluid channelling into the fault zone is required to maintain high pore fluid pressure that would promote fault weakening. Our results show that meteoric waters are primarily responsible for modifying fault zone permeability and for maintaining high pore fluid pressures that may assist episodic earthquake rupture.

Analytical solution of two-fluid electro-osmotic flows of viscoelastic fluids.

PubMed

Afonso, A M; Alves, M A; Pinho, F T

2013-04-01

This paper presents an analytical model that describes a two-fluid electro-osmotic flow of stratified fluids with Newtonian or viscoelastic rheological behavior. This is the principle of operation of an electro-osmotic two-fluid pump as proposed by Brask et al. [Tech. Proc. Nanotech., 1, 190-193, 2003], in which an electrically non-conducting fluid is transported by the interfacial dragging viscous force of a conducting fluid that is driven by electro-osmosis. The electric potential in the conducting fluid and the analytical steady flow solution of the two-fluid electro-osmotic stratified flow in a planar microchannel are presented by assuming a planar interface between the two immiscible fluids with Newtonian or viscoelastic rheological behavior. The effects of fluid rheology, shear viscosity ratio, holdup and interfacial zeta potential are analyzed to show the viability of this technique, where an enhancement of the flow rate is observed as the shear-thinning effects are increased. Copyright © 2012 Elsevier Inc. All rights reserved.

Heat pump with freeze-up prevention

DOEpatents

Ecker, Amir L.

1981-01-01

What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid prevents freeze up of the second heat exchanger by keeping the temperature above the dew point; and, optionally, provides heat for efficient operation.

Rebound and jet formation of a fluid-filled sphere

NASA Astrophysics Data System (ADS)

Killian, Taylor W.; Klaus, Robert A.; Truscott, Tadd T.

2012-12-01

This study investigates the impact dynamics of hollow elastic spheres partially filled with fluid. Unlike an empty sphere, the internal fluid mitigates some of the rebound through an impulse driven exchange of energy wherein the fluid forms a jet inside the sphere. Surprisingly, this occurs on the second rebound or when the free surface is initially perturbed. Images gathered through experimentation show that the fluid reacts more quickly to the impact than the sphere, which decouples the two masses (fluid and sphere), imparts energy to the fluid, and removes rebound energy from the sphere. The experimental results are analyzed in terms of acceleration, momentum and an energy method suggesting an optimal fill volume in the neighborhood of 30%. While the characteristics of the fluid (i.e., density, viscosity, etc.) affect the fluid motion (i.e., type and size of jet formation), the rebound characteristics remain similar for a given fluid volume independent of fluid type. Implications of this work are a potential use of similar passive damping systems in sports technology and marine engineering.

Efficacy of intravenous fluid warming during goal-directed fluid therapy in patients undergoing laparoscopic colorectal surgery: a randomized controlled trial.

PubMed

Choi, Ji-Won; Kim, Duk-Kyung; Lee, Seung-Won; Park, Jung-Bo; Lee, Gyu-Hong

2016-06-01

To evaluate the clinical efficacy of intravenous (IV) fluid warming in patients undergoing laparoscopic colorectal surgery. Adult patients undergoing laparoscopic colorectal surgery were randomly assigned to receive either IV fluids at room temperature (control group) or warmed IV fluids (warm fluids group). Each patient received a standardized goal-directed fluid regimen based on stroke volume variances. Oesophageal temperature was measured at 15 min intervals for 2 h after induction of anaesthesia. A total of 52 patients were enrolled in the study. The drop in core temperature in the warm fluids group was significantly less than in the control group 2 h after the induction of anaesthesia. This significant difference was seen from 30 min after induction. IV fluid warming was associated with a smaller drop in core temperature than room temperature IV fluids in laparoscopic colorectal surgery incorporating goal-directed fluid therapy. © The Author(s) 2016.

Heater-mixer for stored fluids

NASA Technical Reports Server (NTRS)

Canning, T. N. (Inventor)

1974-01-01

A fluid storage vessel for containing cryogenic fluids is described. The storage vessel contains an auxiliary chamber which is connected to the main container by a jet nozzle. The wall of the auxiliary vessel is heat cycled to produce a corresponding expansion and contraction of the fluid within the auxiliary chamber. This action causes heating and mixing of the stored fluid by means of jetting the expanded fluid to and from relative to the stored fluid contents of the vessel.

Fluid sampling device

NASA Technical Reports Server (NTRS)

Studenick, D. K. (Inventor)

1977-01-01

An inlet leak is described for sampling gases, more specifically, for selectively sampling multiple fluids. This fluid sampling device includes a support frame. A plurality of fluid inlet devices extend through the support frame and each of the fluid inlet devices include a longitudinal aperture. An opening device that is responsive to a control signal selectively opens the aperture to allow fluid passage. A closing device that is responsive to another control signal selectively closes the aperture for terminating further fluid flow.

Fluid extravasation during hip arthroscopy.

PubMed

Stafford, Giles H; Malviya, Ajay; Villar, Richard N

2011-01-01

The amount of fluid that may be lost into the soft tissues during hip arthroscopic surgery is unknown. We measured the volumes of irrigation fluid infused, operating time, fluid pressures and volumes of fluid recovered in 36 therapeutic hip arthroscopies. We excluded those where fluid was lost to the floor, leaving 28 patients. The majority were undergoing surgery for the treatment of femoroacetabular impingement. In 5 patients an intra-articular contrast medium was instilled, in order to establish the likely location of any extravasated fluid. The mean operating time was 68 minutes (31 to 120), and the mean infusion pressure was 46 mm Hg (30 to 70). The mean volume of infused fluid was 9677 ml (95% confidence interval (CI) 7715 to 11638) and the mean volume of fluid recovered was 8544 ml (95% CI 6715 to 10373). The mean fluid extravasation loss into the peri-articular tissues was 1132 ml (95% CI 808 ml to 1456 ml). There was a significant correlation between the volume of extravasated fluid and both the length of operation and the volume of infused fluid used. We had no adverse events in our series. During arthroscopic hip surgery more than a litre of irrigation fluid may be extravasated into the soft tissues. In order to reduce problems related to this we attempt to keep operating times low, and maintain intra-operative fluid pressures as low as possible.

Four phases of intravenous fluid therapy: a conceptual model.

PubMed

Hoste, E A; Maitland, K; Brudney, C S; Mehta, R; Vincent, J-L; Yates, D; Kellum, J A; Mythen, M G; Shaw, A D

2014-11-01

I.V. fluid therapy plays a fundamental role in the management of hospitalized patients. While the correct use of i.v. fluids can be lifesaving, recent literature demonstrates that fluid therapy is not without risks. Indeed, the use of certain types and volumes of fluid can increase the risk of harm, and even death, in some patient groups. Data from a recent audit show us that the inappropriate use of fluids may occur in up to 20% of patients receiving fluid therapy. The delegates of the 12th Acute Dialysis Quality Initiative (ADQI) Conference sought to obtain consensus on the use of i.v. fluids with the aim of producing guidance for their use. In this article, we review a recently proposed model for fluid therapy in severe sepsis and propose a framework by which it could be adopted for use in most situations where fluid management is required. Considering the dose-effect relationship and side-effects of fluids, fluid therapy should be regarded similar to other drug therapy with specific indications and tailored recommendations for the type and dose of fluid. By emphasizing the necessity to individualize fluid therapy, we hope to reduce the risk to our patients and improve their outcome. © The Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Automatic fluid dispenser

NASA Technical Reports Server (NTRS)

Sakellaris, P. C. (Inventor)

1977-01-01

Fluid automatically flows to individual dispensing units at predetermined times from a fluid supply and is available only for a predetermined interval of time after which an automatic control causes the fluid to drain from the individual dispensing units. Fluid deprivation continues until the beginning of a new cycle when the fluid is once again automatically made available at the individual dispensing units.

40 CFR 60.105a - Monitoring of emissions and operations for fluid catalytic cracking units (FCCU) and fluid coking...

Code of Federal Regulations, 2011 CFR

2011-07-01

... for fluid catalytic cracking units (FCCU) and fluid coking units (FCU). 60.105a Section 60.105a... and operations for fluid catalytic cracking units (FCCU) and fluid coking units (FCU). (a) FCCU and... Emission Standards for Hazardous Air Pollutants for Petroleum Refineries: Catalytic Cracking Units...

40 CFR 60.105a - Monitoring of emissions and operations for fluid catalytic cracking units (FCCU) and fluid coking...

Code of Federal Regulations, 2010 CFR

2010-07-01

... for fluid catalytic cracking units (FCCU) and fluid coking units (FCU). 60.105a Section 60.105a... and operations for fluid catalytic cracking units (FCCU) and fluid coking units (FCU). (a) FCCU and... Emission Standards for Hazardous Air Pollutants for Petroleum Refineries: Catalytic Cracking Units...

Fluid sampling tool

DOEpatents

Garcia, Anthony R.; Johnston, Roger G.; Martinez, Ronald K.

2000-01-01

A fluid-sampling tool for obtaining a fluid sample from a container. When used in combination with a rotatable drill, the tool bores a hole into a container wall, withdraws a fluid sample from the container, and seals the borehole. The tool collects fluid sample without exposing the operator or the environment to the fluid or to wall shavings from the container.

Heat recovery system series arrangements

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

Kauffman, Justin P.; Welch, Andrew M.; Dawson, Gregory R.

The present disclosure is directed to heat recovery systems that employ two or more organic Rankine cycle (ORC) units disposed in series. According to certain embodiments, each ORC unit includes an evaporator that heats an organic working fluid, a turbine generator set that expands the working fluid to generate electricity, a condenser that cools the working fluid, and a pump that returns the working fluid to the evaporator. The heating fluid is directed through each evaporator to heat the working fluid circulating within each ORC unit, and the cooling fluid is directed through each condenser to cool the working fluidmore » circulating within each ORC unit. The heating fluid and the cooling fluid flow through the ORC units in series in the same or opposite directions.« less

Miniaturized pressurization system

DOEpatents

Whitehead, John C.; Swink, Don G.

1991-01-01

The invention uses a fluid stored at a low pressure and provides the fluid at a high pressure. The invention allows the low pressure fluid to flow to a fluid bore of a differential pump and from the pump to a fluid pressure regulator. After flowing through the regulator the fluid is converted to a gas which is directed to a gas bore of the differential pump. By controlling the flow of gas entering and being exhausted from the gas bore, the invention provides pressure to the fluid. By setting the regulator, the high pressure fluid can be set at predetermined values. Because the invention only needs a low pressure fluid, the inventive apparatus has a low mass, and therefore would be useful in rocket propulsion systems.

Fluid evolution during burial and Variscan deformation in the Lower Devonian rocks of the High-Ardenne slate belt (Belgium): sources and causes of high-salinity and C-O-H-N fluids

NASA Astrophysics Data System (ADS)

Kenis, I.; Muchez, Ph.; Verhaert, G.; Boyce, A.; Sintubin, M.

2005-08-01

Fluid inclusions in quartz veins of the High-Ardenne slate belt have preserved remnants of prograde and retrograde metamorphic fluids. These fluids were examined by petrography, microthermometry and Raman analysis to define the chemical and spatial evolution of the fluids that circulated through the metamorphic area of the High-Ardenne slate belt. The earliest fluid type was a mixed aqueous/gaseous fluid (H2O-NaCl-CO2-(CH4-N2)) occurring in growth zones and as isolated fluid inclusions in both the epizonal and anchizonal part of the metamorphic area. In the central part of the metamorphic area (epizone), in addition to this mixed aqueous/gaseous fluid, primary and isolated fluid inclusions are also filled with a purely gaseous fluid (CO2-N2-CH4). During the Variscan orogeny, the chemical composition of gaseous fluids circulating through the Lower Devonian rocks in the epizonal part of the slate belt, evolved from an earlier CO2-CH4-N2 composition to a later composition enriched in N2. Finally, a late, Variscan aqueous fluid system with a H2O-NaCl composition migrated through the Lower Devonian rocks. This latest type of fluid can be observed in and outside the epizonal metamorphic part of the High-Ardenne slate belt. The chemical composition of the fluids throughout the metamorphic area, shows a direct correlation with the metamorphic grade of the host rock. In general, the proportion of non-polar species (i.e. CO2, CH4, N2) with respect to water and the proportion of non-polar species other than CO2 increase with increasing metamorphic grade within the slate belt. In addition to this spatial evolution of the fluids, the temporal evolution of the gaseous fluids is indicative for a gradual maturation due to metamorphism in the central part of the basin. In addition to the maturity of the metamorphic fluids, the salinity of the aqueous fluids also shows a link with the metamorphic grade of the host-rock. For the earliest and latest fluid inclusions in the anchizonal part of the High-Ardenne slate belt the salinity varies respectively between 0 and 3.5 eq.wt% NaCl and between 0 and 2.7 eq.wt% NaCl, while in the epizonal part the salinity varies between 0.6 and 17 eq.wt% NaCl and between 3 and 10.6 eq.wt% for the earliest and latest aqueous fluid inclusions, respectively. Although high salinity fluids are often attributed to the original sedimentary setting, the increasing salinity of the fluids that circulated through the Lower Devonian rocks in the High-Ardenne slate belt can be directly attributed to regional metamorphism. More specifically the salinity of the primary fluid inclusions is related to hydrolysis reactions of Cl-bearing minerals during prograde metamorphism, while the salinity of the secondary fluid inclusions is rather related to hydration reactions during retrograde metamorphism. The temporal and spatial distribution of the fluids in the High-Ardenne slate belt are indicative for a closed fluid flow system present in the Lower Devonian rocks during burial and Variscan deformation, where fluids were in thermal and chemical equilibrium with the host rock. Such a closed fluid flow system is confirmed by stable isotope study of the veins and their adjacent host rock for which uniform δ180 values of both the veins and their host rock demonstrate a rock-buffered fluid flow system.

Fluid-related inclusions in Alpine high-pressure peridotite reveal trace element recycling during subduction-zone dehydration of serpentinized mantle (Cima di Gagnone, Swiss Alps)

NASA Astrophysics Data System (ADS)

Scambelluri, Marco; Pettke, Thomas; Cannaò, Enrico

2015-11-01

Serpentinites release at sub-arc depths volatiles and several fluid-mobile trace elements found in arc magmas. Constraining element uptake in these rocks and defining the trace element composition of fluids released upon serpentinite dehydration can improve our understanding of mass transfer across subduction zones and to volcanic arcs. The eclogite-facies garnet metaperidotite and chlorite harzburgite bodies embedded in paragneiss of the subduction melange from Cima di Gagnone derive from serpentinized peridotite protoliths and are unique examples of ultramafic rocks that experienced subduction metasomatism and devolatilization. In these rocks, metamorphic olivine and garnet trap polyphase inclusions representing the fluid released during high-pressure breakdown of antigorite and chlorite. Combining major element mapping and laser-ablation ICP-MS bulk inclusion analysis, we characterize the mineral content of polyphase inclusions and quantify the fluid composition. Silicates, Cl-bearing phases, sulphides, carbonates, and oxides document post-entrapment mineral growth in the inclusions starting immediately after fluid entrapment. Compositional data reveal the presence of two different fluid types. The first (type A) records a fluid prominently enriched in fluid-mobile elements, with Cl, Cs, Pb, As, Sb concentrations up to 103 PM (primitive mantle), ∼102 PM Tl, Ba, while Rb, B, Sr, Li, U concentrations are of the order of 101 PM, and alkalis are ∼2 PM. The second fluid (type B) has considerably lower fluid-mobile element enrichments, but its enrichment patterns are comparable to type A fluid. Our data reveal multistage fluid uptake in these peridotite bodies, including selective element enrichment during seafloor alteration, followed by fluid-rock interaction along with subduction metamorphism in the plate interface melange. Here, infiltration of sediment-equilibrated fluid produced significant enrichment of the serpentinites in As, Sb, B, Pb, an enriched trace element pattern that was then transferred to the fluid released at greater depth upon serpentine dehydration (type A fluid). The type B fluid hosted by garnet may record the composition of the chlorite breakdown fluid released at even greater depth. The Gagnone study-case demonstrates that serpentinized peridotites acquire water and fluid-mobile elements during ocean floor hydration and through exchange with sediment-equilibrated fluids in the early subduction stages. Subsequent antigorite devolatilization at subarc depths delivers aqueous fluids to the mantle wedge that can be prominently enriched in sediment-derived components, potentially triggering arc magmatism without the need of concomitant dehydration/melting of metasediments or altered oceanic crust.

Three insulation methods to minimize intravenous fluid administration set heat loss.

PubMed

Piek, Richardt; Stein, Christopher

2013-01-01

To assess the effect of three methods for insulating an intravenous (IV) fluid administration set on the temperature of warmed fluid delivered rapidly in a cold environment. The three chosen techniques for insulation of the IV fluid administration set involved enclosing the tubing of the set in 1) a cotton conforming bandage, 2) a reflective emergency blanket, and 3) a combination of technique 2 followed by technique 1. Intravenous fluid warmed to 44°C was infused through a 20-drop/mL 180-cm-long fluid administration set in a controlled environmental temperature of 5°C. Temperatures in the IV fluid bag, the distal end of the fluid administration set, and the environment were continuously measured with resistance thermosensors. Twenty repetitions were performed in four conditions, namely, a control condition (with no insulation) and the three different insulation methods described above. One-way analysis of variance was used to assess the mean difference in temperature between the IV fluid bag and the distal fluid administration set under the four conditions. In the control condition, a mean of 5.28°C was lost between the IV fluid bag and the distal end of the fluid administration set. There was a significant difference found between the four conditions (p < 0.001). A mean of 3.53°C was lost between the IV fluid bag and the distal end of the fluid administration set for both the bandage and reflective emergency blanket, and a mean of 3.06°C was lost when the two methods were combined. Using inexpensive and readily available materials to insulate a fluid administration set can result in a reduction of heat loss in rapidly infused, warmed IV fluid in a cold environment.

Persistent Homology to describe Solid and Fluid Structures during Multiphase Flow

NASA Astrophysics Data System (ADS)

Herring, A. L.; Robins, V.; Liu, Z.; Armstrong, R. T.; Sheppard, A.

2017-12-01

The question of how to accurately and effectively characterize essential fluid and solid distributions and structures is a long-standing topic within the field of porous media and fluid transport. For multiphase flow applications, considerable research effort has been made to describe fluid distributions under a range of conditions; including quantification of saturation levels, fluid-fluid pressure differences and interfacial areas, and fluid connectivity. Recent research has effectively used topological metrics to describe pore space and fluid connectivity, with researchers demonstrating links between pore-scale nonwetting phase topology to fluid mobilization and displacement mechanisms, relative permeability, fluid flow regimes, and thermodynamic models of multiphase flow. While topology is clearly a powerful tool to describe fluid distribution, topological metrics by definition provide information only on the connectivity of a phase, not its geometry (shape or size). Physical flow characteristics, e.g. the permeability of a fluid phase within a porous medium, are dependent on the connectivity of the pore space or fluid phase as well as the size of connections. Persistent homology is a technique which provides a direct link between topology and geometry via measurement of topological features and their persistence from the signed Euclidean distance transform of a segmented digital image (Figure 1). We apply persistent homology analysis to measure the occurrence and size of pore-scale topological features in a variety of sandstones, for both the dry state and the nonwetting phase fluid during two-phase fluid flow (drainage and imbibition) experiments, visualized with 3D X-ray microtomography. The results provide key insights into the dominant topological features and length scales of a media which control relevant field-scale engineering properties such as fluid trapping, absolute permeability, and relative permeability.

The Chemical Behavior of Fluids Released during Deep Subduction Based on Fluid Inclusions

NASA Astrophysics Data System (ADS)

Frezzotti, M. L.; Ferrando, S.

2014-12-01

We present a review of current research on fluid inclusions in (HP-) UHP metamorphic rocks that, combined with existing experimental research and thermodynamic models, allow us to investigate the chemical and physical properties of fluids released during deep subduction, their solvent and element transport capacity, and the subsequent implications for the element recycling in the mantle wedge. An impressive number of fluid inclusion studies indicate three main populations of fluid inclusions in HP and UHP metamorphic rocks: i) aqueous and/or non-polar gaseous fluid inclusions (FI), ii) multiphase solid inclusions (MSI), and iii) melt inclusions (MI). Chemical data from preserved fluid inclusions in rocks match with and implement "model" fluids by experiments and thermodynamics, revealing a continuity behind the extreme variations of physico-chemical properties of subduction-zone fluids. From fore-arc to sub-arc depths, fluids released by progressive devolatilization reactions from slab lithologies change from relatively diluted chloride-bearing aqueous solutions (± N2), mainly influenced by halide ligands, to (alkali) aluminosilicate-rich aqueous fluids, in which polymerization probably governs the solubility and transport of major (e.g., Si and Al) and trace elements (including C). Fluid inclusion data implement the petrological models explaining deep volatile liberation in subduction zones, and their flux into the mantle wedge.

Fluids in crustal deformation: Fluid flow, fluid-rock interactions, rheology, melting and resources

NASA Astrophysics Data System (ADS)

Lacombe, Olivier; Rolland, Yann

2016-11-01

Fluids exert a first-order control on the structural, petrological and rheological evolution of the continental crust. Fluids interact with rocks from the earliest stages of sedimentation and diagenesis in basins until these rocks are deformed and/or buried and metamorphosed in orogens, then possibly exhumed. Fluid-rock interactions lead to the evolution of rock physical properties and rock strength. Fractures and faults are preferred pathways for fluids, and in turn physical and chemical interactions between fluid flow and tectonic structures, such as fault zones, strongly influence the mechanical behaviour of the crust at different space and time scales. Fluid (over)pressure is associated with a variety of geological phenomena, such as seismic cycle in various P-T conditions, hydrofracturing (including formation of sub-horizontal, bedding-parallel veins), fault (re)activation or gravitational sliding of rocks, among others. Fluid (over)pressure is a governing factor for the evolution of permeability and porosity of rocks and controls the generation, maturation and migration of economic fluids like hydrocarbons or ore forming hydrothermal fluids, and is therefore a key parameter in reservoir studies and basin modeling. Fluids may also help the crust partially melt, and in turn the resulting melt may dramatically change the rheology of the crust.

Passive filtration of air egressing from nuclear containment

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

Malloy, III, John D

2017-09-26

A nuclear reactor includes a reactor core comprising fissile material disposed in a reactor pressure vessel. A radiological containment contains the nuclear reactor. A containment compartment contains the radiological containment. A heat sink includes a chimney configured to develop an upward-flowing draft in response to heated fluid flowing into a lower portion of the chimney. A fluid conduit is arranged to receive fluid from the containment compartment and to discharge into the chimney. A filter may be provided, with the fluid conduit including a first fluid conduit arranged to receive fluid from the containment compartment and to discharge into anmore » inlet of the filter, and a second fluid conduit arranged to receive fluid from an outlet of the filter and to discharge into the chimney. As the draft is developed passively, there is no need for a blower or pump configured to move fluid through the fluid conduit.« less

A General Approach for Fluid Patterning and Application in Fabricating Microdevices.

PubMed

Huang, Zhandong; Yang, Qiang; Su, Meng; Li, Zheng; Hu, Xiaotian; Li, Yifan; Pan, Qi; Ren, Wanjie; Li, Fengyu; Song, Yanlin

2018-06-19

Engineering the fluid interface such as the gas-liquid interface is of great significance for solvent processing applications including functional material assembly, inkjet printing, and high-performance device fabrication. However, precisely controlling the fluid interface remains a great challenge owing to its flexibility and fluidity. Here, a general method to manipulate the fluid interface for fluid patterning using micropillars in the microchannel is reported. The principle of fluid patterning for immiscible fluid pairs including air, water, and oils is proposed. This understanding enables the preparation of programmable multiphase fluid patterns and assembly of multilayer functional materials to fabricate micro-optoelectronic devices. This general strategy of fluid patterning provides a promising platform to study the fundamental processes occurring on the fluid interface, and benefits applications in many subjects, such as microfluidics, microbiology, chemical analysis and detection, material synthesis and assembly, device fabrication, etc. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The role of fluid overload in the prediction of outcome in acute kidney injury.

PubMed

Selewski, David T; Goldstein, Stuart L

2018-01-01

Our understanding of the epidemiology and the impact of acute kidney injury (AKI) and fluid overload on outcomes has improved significantly over the past several decades. Fluid overload occurs commonly in critically ill children with and without associated AKI. Researchers in pediatric AKI have been at the forefront of describing the impact of fluid overload on outcomes in a variety of populations. A full understanding of this topic is important as fluid overload represents a potentially modifiable risk factor and a target for intervention. In this state-of-the-art review, we comprehensively describe the definition of fluid overload, the impact of fluid overload on kidney function, the impact of fluid overload on the diagnosis of AKI, the association of fluid overload with outcomes, the targeted therapy of fluid overload, and the impact of the timing of renal replacement therapy on outcomes.

Methods and systems for integrating fluid dispensing technology with stereolithography

DOEpatents

Medina, Francisco; Wicker, Ryan; Palmer, Jeremy A.; Davis, Don W.; Chavez, Bart D.; Gallegos, Phillip L.

2010-02-09

An integrated system and method of integrating fluid dispensing technologies (e.g., direct-write (DW)) with rapid prototyping (RP) technologies (e.g., stereolithography (SL)) without part registration comprising: an SL apparatus and a fluid dispensing apparatus further comprising a translation mechanism adapted to translate the fluid dispensing apparatus along the Z-, Y- and Z-axes. The fluid dispensing apparatus comprises: a pressurized fluid container; a valve mechanism adapted to control the flow of fluid from the pressurized fluid container; and a dispensing nozzle adapted to deposit the fluid in a desired location. To aid in calibration, the integrated system includes a laser sensor and a mechanical switch. The method further comprises building a second part layer on top of the fluid deposits and optionally accommodating multi-layered circuitry by incorporating a connector trace. Thus, the present invention is capable of efficiently building single and multi-material SL fabricated parts embedded with complex three-dimensional circuitry using DW.

Self-charging metering and dispensing device for fluids

NASA Technical Reports Server (NTRS)

Hooper, S. L.; Setzer, D. (Inventor)

1984-01-01

A self-metering and dispensing device for fluids obtained from a pressurized fluid supply is discussed. Tubing and valving means permit the introduction of fluid into and discharge from a closed cylindrical reservoir. The reservoir contains a slideably disposed piston co-acting with a coil compression spring, with piston travel determining the amount of fluid in the reservoir. Once the determined amount of fluid is introduced into the reservoir, the fluid is discharged by the force of the coil compression spring acting upon the piston.

Integrated hydraulic cooler and return rail in camless cylinder head

DOEpatents

Marriott, Craig D [Clawson, MI; Neal, Timothy L [Ortonville, MI; Swain, Jeff L [Flushing, MI; Raimao, Miguel A [Colorado Springs, CO

2011-12-13

An engine assembly may include a cylinder head defining an engine coolant reservoir, a pressurized fluid supply, a valve actuation assembly, and a hydraulic fluid reservoir. The valve actuation assembly may be in fluid communication with the pressurized fluid supply and may include a valve member displaceable by a force applied by the pressurized fluid supply. The hydraulic fluid reservoir may be in fluid communication with the valve actuation assembly and in a heat exchange relation to the engine coolant reservoir.

Ultrasonic fluid densitometry and densitometer

DOEpatents

Greenwood, Margaret S.; Lail, Jason C.

1998-01-01

The present invention is an ultrasonic fluid densitometer that uses a material wedge having an acoustic impedance that is near the acoustic impedance of the fluid, specifically less than a factor of 11 greater than the acoustic impedance of the fluid. The invention also includes a wedge having at least two transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface.

Ultrasonic fluid densitometry and densitometer

DOEpatents

Greenwood, M.S.; Lail, J.C.

1998-01-13

The present invention is an ultrasonic fluid densitometer that uses a material wedge having an acoustic impedance that is near the acoustic impedance of the fluid, specifically less than a factor of 11 greater than the acoustic impedance of the fluid. The invention also includes a wedge having at least two transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface. 6 figs.

Magnetic particle translation as a surrogate measure for synovial fluid mechanics.

PubMed

Shah, Yash Y; Maldonado-Camargo, Lorena; Patel, Neal S; Biedrzycki, Adam H; Yarmola, Elena G; Dobson, Jon; Rinaldi, Carlos; Allen, Kyle D

2017-07-26

The mechanics of synovial fluid vary with disease progression, but are difficult to quantify quickly in a clinical setting due to small sample volumes. In this study, a novel technique to measure synovial fluid mechanics using magnetic nanoparticles is introduced. Briefly, microspheres embedded with superparamagnetic iron oxide nanoparticles, termed magnetic particles, are distributed through a 100μL synovial fluid sample. Then, a permanent magnet inside a protective sheath is inserted into the synovial fluid sample. Magnetic particles translate toward the permanent magnet and the percentage of magnetic particles collected by the magnet in a given time can be related to synovial fluid viscosity. To validate this relationship, magnetic particle translation was demonstrated in three phases. First, magnetic particle translation was assessed in glycerol solutions with known viscosities, demonstrating that as fluid viscosity increased, magnetic particle translation decreased. Next, the relationship between magnetic particle translation and synovial fluid viscosity was assessed using bovine synovial fluid that was progressively degenerated via ultrasonication. Here, particle collection in a given amount of time increased as fluid degenerated, demonstrating that the relationship between particle collection and fluid mechanics holds in non-Newtonian synovial fluid. Finally, magnetic particle translation was used to assess differences between healthy and OA affected joints in equine synovial fluid. Here, particle collection in a given time was higher in OA joints relative to healthy horses (p<0.001). Combined, these data demonstrate potential viability of magnetic particle translation in a clinical setting to evaluate synovial fluid mechanics in limited volumes of synovial fluid sample. Copyright © 2017 Elsevier Ltd. All rights reserved.

Stroke volume variation as a guide for fluid resuscitation in patients undergoing large-volume liposuction.

PubMed

Jain, Anil Kumar; Khan, Asma M

2012-09-01

: The potential for fluid overload in large-volume liposuction is a source of serious concern. Fluid management in these patients is controversial and governed by various formulas that have been advanced by many authors. Basically, it is the ratio of what goes into the patient and what comes out. Central venous pressure has been used to monitor fluid therapy. Dynamic parameters, such as stroke volume and pulse pressure variation, are better predictors of volume responsiveness and are superior to static indicators, such as central venous pressure and pulmonary capillary wedge pressure. Stroke volume variation was used in this study to guide fluid resuscitation and compared with one guided by an intraoperative fluid ratio of 1.2 (i.e., Rohrich formula). : Stroke volume variation was used as a guide for intraoperative fluid administration in 15 patients subjected to large-volume liposuction. In another 15 patients, fluid resuscitation was guided by an intraoperative fluid ratio of 1.2. The amounts of intravenous fluid administered in the groups were compared. : The mean amount of fluid infused was 561 ± 181 ml in the stroke volume variation group and 2383 ± 1208 ml in the intraoperative fluid ratio group. The intraoperative fluid ratio when calculated for the stroke volume variation group was 0.936 ± 0.084. All patients maintained hemodynamic parameters (heart rate and systolic, diastolic, and mean blood pressure). Renal and metabolic indices remained within normal limits. : Stroke volume variation-guided fluid application could result in an appropriate amount of intravenous fluid use in patients undergoing large-volume liposuction. : Therapeutic, II.

Heat exchanger with intermediate evaporating and condensing fluid

DOEpatents

Fraas, Arthur P.

1978-01-01

A shell and tube-type heat exchanger, such as a liquid sodium-operated steam generator for use in nuclear reactors, comprises a shell containing a primary fluid tube bundle, a secondary fluid tube bundle at higher elevation, and an intermediate fluid vaporizing at the surface of the primary fluid tubes and condensing at the surface of the secondary fluid tubes.

Fluid cooled electrical assembly

DOEpatents

Rinehart, Lawrence E.; Romero, Guillermo L.

2007-02-06

A heat producing, fluid cooled assembly that includes a housing made of liquid-impermeable material, which defines a fluid inlet and a fluid outlet and an opening. Also included is an electrical package having a set of semiconductor electrical devices supported on a substrate and the second major surface is a heat sink adapted to express heat generated from the electrical apparatus and wherein the second major surface defines a rim that is fit to the opening. Further, the housing is constructed so that as fluid travels from the fluid inlet to the fluid outlet it is constrained to flow past the opening thereby placing the fluid in contact with the heat sink.

Basic setup and disinfection.

PubMed

Shimada, Hiroyuki

2014-01-01

Vitrectomy is one of the ophthalmic surgeries that require a large number of instruments. Despite a growing array of single-use disposable instruments, vitrectomies for refractory diseases still involve complicated procedures and many surgical devices. As to the arrangement of materials and instruments on the surgical table, fluids that must not be introduced intraocularly, infusion fluid for washing the ocular surface, fluids for intraocular injection, and fluids for periocular injection are classified and marked to avoid using the wrong fluid. Since bacteria are present in the fluid retained in the fluid catch bag, the accumulated infusion fluid should be removed by aspiration. © 2014 S. Karger AG, Basel

Damping of a fluid-conveying pipe surrounded by a viscous annulus fluid

NASA Astrophysics Data System (ADS)

Kjolsing, Eric J.; Todd, Michael D.

2017-04-01

To further the development of a downhole vibration based energy harvester, this study explores how fluid velocity affects damping in a fluid-conveying pipe stemming from a viscous annulus fluid. A linearized equation of motion is formed which employs a hydrodynamic forcing function to model the annulus fluid. The system is solved in the frequency domain through the use of the spectral element method. The three independent variables investigated are the conveyed fluid velocity, the rotational stiffness of the boundary (using elastic springs), and the annulus fluid viscosity. It was found that, due to the hydrodynamic functions frequency-dependence, increasing the conveyed fluid velocity increases the systems damping ratio. It was also noted that stiffer systems saw the damping ratio increase at a slower rate when compared to flexible systems as the conveyed fluid velocity was increased. The results indicate that overestimating the stiffness of a system can lead to underestimated damping ratios and that this error is made worse if the produced fluid velocity or annulus fluid viscosity is underestimated. A numeric example was provided to graphically illustrate these errors. Approved for publication, LA-UR-15-28006.

Data center coolant switch

DOEpatents

Iyengar, Madhusudan K.; Parida, Pritish R.; Schultz, Mark D.

2015-10-06

A data center cooling system is operated in a first mode; it has an indoor portion wherein heat is absorbed from components in the data center, and an outdoor heat exchanger portion wherein outside air is used to cool a first heat transfer fluid (e.g., water) present in at least the outdoor heat exchanger portion of the cooling system during the first mode. The first heat transfer fluid is a relatively high performance heat transfer fluid (as compared to the second fluid), and has a first heat transfer fluid freezing point. A determination is made that an appropriate time has been reached to switch from the first mode to a second mode. Based on this determination, the outdoor heat exchanger portion of the data cooling system is switched to a second heat transfer fluid, which is a relatively low performance heat transfer fluid, as compared to the first heat transfer fluid. It has a second heat transfer fluid freezing point lower than the first heat transfer fluid freezing point, and the second heat transfer fluid freezing point is sufficiently low to operate without freezing when the outdoor air temperature drops below a first predetermined relationship with the first heat transfer fluid freezing point.

Fast fluid-flow events within a subduction-related vein system in oceanic eclogite: implications for pore fluid pressure at the plate interface

NASA Astrophysics Data System (ADS)

Taetz, Stephan; John, Timm; Bröcker, Michael; Spandler, Carl; Stracke, Andreas

2017-04-01

A better understanding of the subduction zone fluid cycle and its mechanical feedback requires in-depth knowledge of how fluids flow within and out of the descending slabs. In order to develop reliable quantitative models of fluid flow, the general relationship between dehydration reactions, fluid pathway formation, and the dimensions and timescales of distinct fluid flow events have to be explored. The high-pressure/low-temperature metamorphic rocks of the Pouébo Eclogite Mélange in New Caledonia provide an excellent opportunity to study the fluid flux in a subduction zone setting. Fluid dynamics are recorded by high-pressure veins that cross-cut eclogite facies mélange blocks from this occurrence. Two types of garnet-quartz-phengite veins can be distinguished. These veins record both synmetamorphic internal fluid release by mineral breakdown reactions (type I veins) as well as infiltration of an external fluid (type II veins) and the associated formation of a reaction halo. The overall dehydration, fluid accumulation and fluid migration documented by the type I veins occurred on a timescale of 10^5-106 years that is mainly given by the geometry and convergence rate of the subduction system. In order to quantify the timeframe of fluid-rock interaction between the external fluid and the wall-rock, we have applied Li-isotope chronology. A continuous profile was sampled perpendicular to a type II vein including material from the vein, the reaction selvage and the immediate host rock. Additional drill cores were taken from parts of the outcrop that most likely remained completely unaffected by fluid infiltration-induced alteration. Different Li concentrations in the internal and external fluid reservoirs produced a distinct diffusion profile of decreasing Li concentration and increasing δ7Li as the reaction front propagated into the host-rock. Li-chronometric constraints indicate that fluid-rock interaction related to the formation of the type II veins and had been completed within ca. 3 years. The short-lived, pulse-like character of this process is in accordance with the notion that fluid flow related to oceanic crust dehydration at the blueschist-to-eclogite transition contributes to or even dominates episodic pore fluid pressure increases at the plate interface which may trigger slip events reported from many subduction zones.

Perioperative intravenous fluid prescribing: a multi-centre audit.

PubMed

Harris, Benjamin; Schopflin, Christian; Khaghani, Clare; Edwards, Mark

2015-01-01

Excessive or inadequate intravenous fluid given in the perioperative period can affect outcomes. A number of guidelines exist but these can conflict with the entrenched practice, evidence base and prescriber knowledge. We conducted a multi-centre audit of intraoperative and postoperative intravenous fluid therapy to investigate fluid administration practice and frequency of postoperative electrolyte disturbances. A retrospective audit was done in five hospitals of adult patients undergoing elective major abdominal, gastrointestinal tract or orthopaedic surgery. The type, volume and quantity of fluid and electrolytes administered during surgery and in 3 days postoperatively was calculated, and electrolyte disturbances were studied using clinical records. Data from four hundred thirty-one patients in five hospitals covering 1157 intravenous fluid days were collected. Balanced crystalloid solutions were almost universally used in the operating theatre and were also the most common fluid administered postoperatively, followed by hypotonic dextrose-saline solutions and 0.9 % sodium chloride. For three common uncomplicated elective operations, the volume of fluid administered intraoperatively demonstrated considerable variability. Over half of the patients received no postoperative fluid on day 1, and even more were commenced on free oral fluids immediately postoperatively or on day 1. Postoperative quantities of sodium exceeded the recommended amounts for maintenance in half of the patients who continued to receive intravenous fluids. Potassium administration in those receiving intravenous fluids was almost universally inadequate. Hypokalaemia and hyponatraemia were the common findings. We documented the current clinical practice and confirmed that early free oral fluids and cessation of any intravenous fluids is common postoperatively in keeping with the aims of enhanced recovery after surgery programmes. Excessive sodium and water and inadequate potassium in those given intravenous fluids postoperatively is common and needs to be investigated. The variation in intraoperative fluid volume administration for three common procedures is considerable and in keeping with other international studies. Future trials of fluid therapy should include the intraoperative and postoperative phases.

Fluid Film Bearing Code Development

NASA Technical Reports Server (NTRS)

1995-01-01

The next generation of rocket engine turbopumps is being developed by industry through Government-directed contracts. These turbopumps will use fluid film bearings because they eliminate the life and shaft-speed limitations of rolling-element bearings, increase turbopump design flexibility, and reduce the need for turbopump overhauls and maintenance. The design of the fluid film bearings for these turbopumps, however, requires sophisticated analysis tools to model the complex physical behavior characteristic of fluid film bearings operating at high speeds with low viscosity fluids. State-of-the-art analysis and design tools are being developed at the Texas A&M University under a grant guided by the NASA Lewis Research Center. The latest version of the code, HYDROFLEXT, is a thermohydrodynamic bulk flow analysis with fluid compressibility, full inertia, and fully developed turbulence models. It can predict the static and dynamic force response of rigid and flexible pad hydrodynamic bearings and of rigid and tilting pad hydrostatic bearings. The Texas A&M code is a comprehensive analysis tool, incorporating key fluid phenomenon pertinent to bearings that operate at high speeds with low-viscosity fluids typical of those used in rocket engine turbopumps. Specifically, the energy equation was implemented into the code to enable fluid properties to vary with temperature and pressure. This is particularly important for cryogenic fluids because their properties are sensitive to temperature as well as pressure. As shown in the figure, predicted bearing mass flow rates vary significantly depending on the fluid model used. Because cryogens are semicompressible fluids and the bearing dynamic characteristics are highly sensitive to fluid compressibility, fluid compressibility effects are also modeled. The code contains fluid properties for liquid hydrogen, liquid oxygen, and liquid nitrogen as well as for water and air. Other fluids can be handled by the code provided that the user inputs information that relates the fluid transport properties to the temperature.

Optimal probes for withdrawal of uncontaminated fluid samples

NASA Astrophysics Data System (ADS)

Sherwood, J. D.

2005-08-01

Withdrawal of fluid by a composite probe pushed against the face z =0 of a porous half-space z >0 is modeled assuming incompressible Darcy flow. The probe is circular, of radius a, with an inner sampling section of radius αa and a concentric outer guard probe αa βa is saturated with fluid 2; the two fluids have the same viscosity. It is assumed that the interface between the two fluids is sharp and remains so as it moves through the rock. The pressure in the probe is lower than that of the pore fluid in the rock, so that the fluid interface is convected with the fluids towards the probe. This idealized axisymmetric problem is solved numerically, and it is shown that an analysis based on far-field spherical flow towards a point sink is a good approximation when the nondimensional depth of fluid 1 is large, i.e., β ≫1. The inner sampling probe eventually produces pure fluid 2, and this technique has been proposed for sampling pore fluids in rock surrounding an oil well [A. Hrametz, C. Gardner, M. Wais, and M. Proett, U.S. Patent No. 6,301,959 B1 (16 October 2001)]. Fluid 1 is drilling fluid filtrate, which has displaced the original pore fluid (fluid 2), a pure sample of which is required. The time required to collect an uncontaminated sample of original pore fluid can be minimized by a suitable choice of the probe geometry α [J. Sherwood, J. Fitzgerald and B. Hill, U.S. Patent No. 6,719,049 B2 (13 April 2004)]. It is shown that the optimal choice of α depends on the depth of filtrate invasion β and the volume of sample required.

Trace element analyses of fluid-bearing diamonds from Jwaneng, Botswana

NASA Astrophysics Data System (ADS)

Schrauder, Marcus; Koeberl, Christian; Navon, Oded

1996-12-01

Fibrous diamonds from Botswana contain abundant micro-inclusions, which represent syngenetic mantle fluids under high pressure. The major element composition of the fluids within individual diamonds was found to be uniform, but a significant compositional variation exists between different diamond specimens. The composition of the fluids varies between a carbonatitic and a hydrous endmember. To constrain the composition of fluids in the mantle, the trace element contents of thirteen micro-inclusion-bearing fibrous diamonds from Botswana was studied using neutron activation analysis. The concentrations of incompatible elements (including K, Na, Br, Rb, Sr, Zr, Cs, Ba, Hf, Ta, Th, U, and the LREEs) in the fluids are higher than those of mantle-derived rocks and melt inclusions. The compatible elements (e.g., Cr, Co, Ni) have abundances that are similar to those of the primitive mantle. The concentrations of most trace elements decrease by a factor of two from the carbonate-rich fluids to the hydrous fluids. Several models may explain the observed elemental variations. Minerals in equilibrium with the fluid were most likely enriched in incompatible elements, which does not agree with derivation of the fluids by partial melting of common peridotites or eclogites. Fractional crystallization of a kimberlite-like magma at depth may yield carbonatitic fluids with low mg numbers (atomic ratio [Mg/(Mg+Fe)]) and high trace element contents. Fractionation of carbonates and additional phases (e.g., rutile, apatite, zircon) may, in general, explain the concentrations of incompatible elements in the fluids, which preferably partition into these phases. Alternatively, mixing of fluids with compositions similar to those of the two endmembers may explain the observed variation of the elemental contents. The fluids in fibrous diamonds might have equilibrated with mineral inclusions in eclogitic diamonds, while peridotitic diamonds do not show evidence of interaction with these fluids. The chemical composition of the fluids in fibrous diamonds indicates that, at p, T conditions that are characteristic for diamond formation, carbonatitic and hydrous fluids are efficient carriers of incompatible elements.

Personalised fluid resuscitation in the ICU: still a fluid concept?

PubMed

van Haren, Frank

2017-12-28

The administration of intravenous fluid to critically ill patients is one of the most common, but also one of the most fiercely debated, interventions in intensive care medicine. Even though many thousands of patients have been enrolled in large trials of alternative fluid strategies, consensus remains elusive and practice is widely variable. Critically ill patients are significantly heterogeneous, making a one size fits all approach unlikely to be successful.New data from basic, animal, and clinical research suggest that fluid resuscitation could be associated with significant harm. There are several important limitations and concerns regarding fluid bolus therapy as it is currently being used in clinical practice. These include, but are not limited to: the lack of an agreed definition; limited and short-lived physiological effects; no evidence of an effect on relevant patient outcomes; and the potential to contribute to fluid overload, specifically when fluid responsiveness is not assessed and when targets and safety limits are not used.Fluid administration in critically ill patients requires clinicians to integrate abnormal physiological parameters into a clinical decision-making model that also incorporates the likely diagnosis and the likely risk or benefit in the specific patient's context. Personalised fluid resuscitation requires careful attention to the mnemonic CIT TAIT: context, indication, targets, timing, amount of fluid, infusion strategy, and type of fluid.The research agenda should focus on experimental and clinical studies to: improve our understanding of the physiological effects of fluid infusion, e.g. on the glycocalyx; evaluate new types of fluids; evaluate novel fluid minimisation protocols; study the effects of a no-fluid strategy for selected patients and scenarios; and compare fluid therapy with other interventions. The adaptive platform trial design may provide us with the tools to evaluate these types of interventions in the intrinsically heterogeneous intensive care unit population, accounting for the explicit assumption that treatment effects may be heterogeneous.

Overnight fluid shifts in subjects with and without obstructive sleep apnea

PubMed Central

Ding, Ning; Lin, Wei; Zhang, Xi-Long; Ding, Wen-Xiao; Gu, Bing; Ni, Bu-Qing; Zhang, Wei; Zhang, Shi-Jiang

2014-01-01

Objective To investigate the characteristics of baseline body fluid content and overnight fluid shifts between non-obstructive sleep apnea (non-OSA) and obstructive sleep apnea (OSA) subjects. Methods A case-controlled study was performed between February 2013 and January 2014, with 36 (18 OSA and 18 non-OSA) outpatients enrolled in this study. Polysomnographic parameters and results of body fluid were compared between the two groups. Results There were no differences in age, weight, and body mass index (BMI) between groups. Compared with the non-OSA group, OSA group had significantly higher neck circumference (NC) and fluid volume shift in the legs. OSA patients had higher left and right leg fluid indices than non-OSA subjects. There were significant correlations between apnoea-hypopnoea index and baseline fluid indices in both legs as well as the reduction in overnight change in both legs fluid volume. The increase in NC was also significantly correlated with the reduction in overnight change in both legs fluid volume, but not with the change in head and neck fluid volume. There were significant correlations between change in NC and increased fluid shifts in head and neck volume. Conclusions OSA patients had a higher baseline fluid content in both legs as compared with non-OSA subjects, which may be the basic factor with regards to fluid shifts in OSA patients. The increase in head and neck fluid shift volume did not directly correlate with the severity of OSA. PMID:25589967

On the role of fluids in stick-slip dynamics of saturated granular fault gouge using a coupled computational fluid dynamics-discrete element approach

NASA Astrophysics Data System (ADS)

Dorostkar, Omid; Guyer, Robert A.; Johnson, Paul A.; Marone, Chris; Carmeliet, Jan

2017-05-01

The presence of fault gouge has considerable influence on slip properties of tectonic faults and the physics of earthquake rupture. The presence of fluids within faults also plays a significant role in faulting and earthquake processes. In this paper, we present 3-D discrete element simulations of dry and fluid-saturated granular fault gouge and analyze the effect of fluids on stick-slip behavior. Fluid flow is modeled using computational fluid dynamics based on the Navier-Stokes equations for an incompressible fluid and modified to take into account the presence of particles. Analysis of a long time train of slip events shows that the (1) drop in shear stress, (2) compaction of granular layer, and (3) the kinetic energy release during slip all increase in magnitude in the presence of an incompressible fluid, compared to dry conditions. We also observe that on average, the recurrence interval between slip events is longer for fluid-saturated granular fault gouge compared to the dry case. This observation is consistent with the occurrence of larger events in the presence of fluid. It is found that the increase in kinetic energy during slip events for saturated conditions can be attributed to the increased fluid flow during slip. Our observations emphasize the important role that fluid flow and fluid-particle interactions play in tectonic fault zones and show in particular how discrete element method (DEM) models can help understand the hydromechanical processes that dictate fault slip.

Temporal and spatial variation in porosity and compaction pressure for the viscoelastic slab

NASA Astrophysics Data System (ADS)

Morishige, M.; Van Keken, P. E.

2017-12-01

Fluid is considered to play key roles in subduction zones. It triggers various types of earthquakes by elevating pore-fluid pressure or forming hydrous minerals, and it also facilitates magma genesis by lowering the solidus temperatures of mantle and crustal rocks. Several previous numerical studies have worked on how fluid migrates and how porosity changes in time and space, but our knowledge of the fluid behavior remains limited. In this presentation, we demonstrate the detailed fluid behavior in the slab. The main features of this study are that (1) viscoelasticity is included, and that (2) fluid flow toward the inner part of the slab is also considered. We construct 2D and 3D finite element models for viscoelastic slab based on a theory of two-phase flow, which allows us to treat the movement of rock- and fluid- phases simultaneously. We solve the equations for porosity and compaction pressure which is defined as the pressure difference in between the two phases. Fluid source is fixed in time and space, and a uniform slab velocity is imposed for the whole model domain. There are several important parameters affecting the fluid behavior which includes bulk viscosity, bulk modulus, permeability, and fluid viscosity. Among these we fix bulk modulus and change the other parameters to investigate their effects on fluid migration. We find that when bulk viscosity is relatively high, elasticity is dominant and large amount of fluid is trapped in and around the fluid source. In addition, fluid migrates along the fluid source when relatively high ratio of permeability to fluid viscosity is assumed. Fluid generally moves with the slab when the ratio of permeability to fluid viscosity is low. One interesting feature is that in some cases porosity increases also in the deeper part of the fluid source due to the diffusion of compaction pressure. It suggests that the effects of resistance to volume change can be an alternative mechanism to effectively hydrate the inner part in the slab. In 3D, we find that fluid migrates in the maximum-dip direction of the slab. It leads to a fluid focusing where the slab bends away from the trench and it results in the increase in porosity and compaction pressure there. This finding may be useful to explain the observed along-arc variation in short-term slow slip events and the upper plane of double seismic zone.

Regional studies of dolomites and their included fluids: recognizing multiple chemically distinct fluids during the complex diagenetic history of Lower Carboniferous (Mississippian) rocks of the Irish Zn-Pb ore field

NASA Astrophysics Data System (ADS)

Johnson, Aaron W.; Shelton, Kevin L.; Gregg, Jay M.; Somerville, Ian D.; Wright, Wayne R.; Nagy, Zsolt R.

2009-05-01

This study provides a regional framework within which studies of ore-related dolomite and dolomite cements may be placed. Fluid inclusion data indicate the presence of three distinct fluids following early dolomitization: 1) a ubiquitous low-temperature, higher salinity fluid found in saddle dolomite; 2) a low-temperature, lower salinity fluid limited to sub-Waulsortian and Waulsortian carbonates; and 3) a higher temperature, lower salinity fluid found in Waulsortian and supra-Waulsortian rocks. Similar fluids have been reported in ore-associated minerals and postmineralization dolomite (Type 1) and in ore-stage carbonates and sphalerite (Types 2 and 3). The halogen geochemistry of included fluids indicates genesis from evaporated seawater. Type 1 fluids are enriched in chloride relative to bromide, reflecting a component of salinity derived via dissolution of halite or from dehydration of seawater. These data suggest that dolomitization and mineralization of Mississippian rocks in the Midlands requires both regionally extensive and localized fluid flow.

The formation of spikes in the displacement of miscible fluids

NASA Technical Reports Server (NTRS)

Rashidnia, N.; Balasubramaniam, R.; Schroer, R. T.

2004-01-01

We report on experiments in which a more viscous fluid displaces a less viscous one in a vertical cylindrical tube. These experiments were performed using silicone oils in a vertical pipette of small diameter. The more viscous fluid also had a slightly larger density than the less viscous fluid. In the initial configuration, the fluids were at rest, and the interface was nominally flat. A dye was added to the more viscous fluid for ease of observation of the interface between the fluids. The flow was initiated by pumping the more viscous fluid into the less viscous one. The displacement velocity was such that the Reynolds number was smaller than unity and the Peclet number for mass transfer between the fluids was large compared to unity. For upward displacement of the more viscous fluid from an initially stable configuration, an axisymmetric finger was observed under all conditions. However, a needle-shaped spike was seen to propagate from the main finger in many cases, similar to that observed by Petitjeans and Maxworthy for the displacement of a more viscous fluid by a less viscous one.

An Environmental Impact Assessment of Perfluorocarbon Thermal Working Fluid Use On Board Crewed Spacecraft

NASA Technical Reports Server (NTRS)

Perry, Jay L.; Arnold, William a.

2006-01-01

The design and operation of crewed spacecraft requires identifying and evaluating chemical compounds that may present reactivity and compatibility risks with the environmental control and life support (ECLS) system. Such risks must be understood so that appropriate design and operational controls, including specifying containment levels, can be instituted or an appropriate substitute material selected. Operational experience acquired during the International Space Station (ISS) program has found that understanding ECLS system and environmental impact presented by thermal control system working fluids is imperative to safely operating any crewed space exploration vehicle. Perfluorocarbon fluids are used as working fluids in thermal control fluid loops on board the ISS. Also, payload hardware developers have identified perfluorocarbon fluids as preferred thermal control working fluids. Interest in using perfluorocarbon fluids as thermal control system working fluids for future crewed space vehicles and outposts is high. Potential hazards associated with perfluorocarbon fluids are discussed with specific attention given to engineering assessment of ECLS system compatibility, compatibility testing results, and spacecraft environmental impact. Considerations for perfluorocarbon fluid use on crewed spacecraft and outposts are summarized.

Wound fluids: a reflection of the state of healing.

PubMed

Staiano-Coico, L; Higgins, P J; Schwartz, S B; Zimm, A J; Goncalves, J

2000-01-01

Analyzing acute and chronic wound fluids provides an important and intriguing insight into the wound milieu. This review outlines some of the salient features of wound repair and the wound fluid environment. Most studies support the premise that the contents of the wound fluid reflect the status of the wound and can be indicative of whether a wound is on the course of a normal or impaired response to injury. For example, chronic wound fluids often differ from acute wound fluids in their proliferative effects on cells active in healing as well as their proteolytic effects. The authors discuss various cytokines, growth factors, proteinases, and protease inhibitors within wound fluids as well as their effect on wound repair. This review also presents confounding factors affecting interpretation of wound fluid studies, suggesting that further studies need to elucidate mechanisms whereby wound fluids either enhance or inhibit wound repair. So far, wound fluid analysis has yielded tantalizing glimpses of the teeming wound environment. What wound fluid contents tell us about the wound or its clinical care is not yet certain.

Critical asymmetry in renormalization group theory for fluids.

PubMed

Zhao, Wei; Wu, Liang; Wang, Long; Li, Liyan; Cai, Jun

2013-06-21

The renormalization-group (RG) approaches for fluids are employed to investigate critical asymmetry of vapour-liquid equilibrium (VLE) of fluids. Three different approaches based on RG theory for fluids are reviewed and compared. RG approaches are applied to various fluid systems: hard-core square-well fluids of variable ranges, hard-core Yukawa fluids, and square-well dimer fluids and modelling VLE of n-alkane molecules. Phase diagrams of simple model fluids and alkanes described by RG approaches are analyzed to assess the capability of describing the VLE critical asymmetry which is suggested in complete scaling theory. Results of thermodynamic properties obtained by RG theory for fluids agree with the simulation and experimental data. Coexistence diameters, which are smaller than the critical densities, are found in the RG descriptions of critical asymmetries of several fluids. Our calculation and analysis show that the approach coupling local free energy with White's RG iteration which aims to incorporate density fluctuations into free energy is not adequate for VLE critical asymmetry due to the inadequate order parameter and the local free energy functional used in the partition function.

Fast intraslab fluid-flow events linked to pulses of high pore fluid pressure at the subducted plate interface

NASA Astrophysics Data System (ADS)

Taetz, Stephan; John, Timm; Bröcker, Michael; Spandler, Carl; Stracke, Andreas

2018-01-01

A better understanding of the subduction zone fluid cycle and its chemical-mechanical feedback requires in-depth knowledge about how fluids flow within and out of descending slabs. Relicts of fluid-flow systems in exhumed rocks of fossil subduction zones allow for identification of the general relationships between dehydration reactions, fluid pathway formation, the dimensions and timescales of distinct fluid flow events; all of which are required for quantitative models for fluid-induced subduction zone processes. Two types of garnet-quartz-phengite veins can be distinguished in an eclogite-facies mélange block from the Pouébo Eclogite Mélange, New Caledonia. These veins record synmetamorphic internal fluid release by mineral breakdown reactions (type I veins), and infiltration of an external fluid (type II veins) with the associated formation of a reaction selvage. The dehydration and fluid migration documented by the type I veins likely occurred on a timescale of 105-106 years, based on average subduction rates and metamorphic conditions required for mineral dehydration and fluid flow. The timeframe of fluid-rock interaction between the external fluid and the wall-rock of the type II veins is quantified using a continuous bulk-rock Li-diffusion profile perpendicular to a vein and its metasomatic selvage. Differences in Li concentration between the internal and external fluid reservoirs resulted in a distinct diffusion profile (decreasing Li concentration and increasing δ7 Li) as the reaction front propagated into the host rock. Li-chronometric constraints indicate that the timescales of fluid-rock interaction associated with type II vein formation are on the order of 1 to 4 months (0.150-0.08+0.14 years). The short-lived, pulse-like character of this process is consistent with the notion that fluid flow caused by oceanic crust dehydration at the blueschist-to-eclogite transition contributes to or even dominates episodic pore fluid pressure increases at the plate interface, which in turn, may trigger slip events reported from many subduction zones.

Tensiometer and method of determining soil moisture potential in below-grade earthen soil

DOEpatents

Hubbell, J.M.; Mattson, E.D.; Sisson, J.B.

1998-06-02

A tensiometer to in-situ determine below-grade soil moisture, potential of earthen soil includes, (a) an apparatus adapted for insertion into earthen soil below grade, the apparatus having a below-grade portion, and, comprising; (b) a porous material provided in the below-grade portion, the porous material at least in part defining a below-grade first fluid chamber; (c) a first fluid conduit extending outwardly of the first fluid chamber; (d) a first controllable isolation valve provided within the first fluid conduit, the first controllable isolation valve defining a second fluid chamber in fluid communication with the first fluid chamber through the first fluid conduit and the isolation valve, the first controllable isolation valve being received within the below-grade portion; and (e) a pressure transducer in fluid communication with the first fluid chamber, the pressure transducer being received within the below-grade portion. An alternate embodiment includes an apparatus adapted for insertion into earthen soil below grade, the apparatus having a below-grade portion, and including: (1) a porous material provided in the below-grade portion, the porous material at least in part defining a below-grade first fluid chamber; and (2) a pressure sensing apparatus in fluid communication with the first fluid chamber, the pressure sensing apparatus being entirely received within the below-grade portion. A method is also disclosed using the above and other apparatus. 6 figs.

Tensiometer and method of determining soil moisture potential in below-grade earthen soil

DOEpatents

Hubbell, Joel M.; Mattson, Earl D.; Sisson, James B.

1998-01-01

A tensiometer to in situ determine below-grade soil moisture, potential of earthen soil includes, a) an apparatus adapted for insertion into earthen soil below grade, the apparatus having a below-grade portion, and, comprising; b) a porous material provided in the below-grade portion, the porous material at least in part defining a below-grade first fluid chamber; c) a first fluid conduit extending outwardly of the first fluid chamber; d) a first controllable isolation valve provided within the first fluid conduit, the first controllable isolation valve defining a second fluid chamber in fluid communication with the first fluid chamber through the first fluid conduit and the isolation valve, the first controllable isolation valve being received within the below-grade portion; and e) a pressure transducer in fluid communication with the first fluid chamber, the pressure transducer being received within the below-grade portion. An alternate embodiment includes an apparatus adapted for insertion into earthen soil below grade, the apparatus having a below-grade portion, and including: i) a porous material provided in the below-grade portion, the porous material at least in part defining a below-grade first fluid chamber; and ii) a pressure sensing apparatus in fluid communication with the first fluid chamber, the pressure sensing apparatus being entirely received within the below-grade portion. A method is also disclosed using the above and other apparatus.

Space station integrated propulsion and fluid system study: Fluid systems configuration databook

NASA Technical Reports Server (NTRS)

Rose, L.; Bicknell, B.; Bergman, D.; Wilson, S.

1987-01-01

This databook contains fluid system requirements and system descriptions for Space Station program elements including the United States and International modules, integrated fluid systems, attached payloads, fluid servicers and vehicle accommodation facilities. Separate sections are devoted to each of the program elements and include a discussion of the overall system requirements, specific fluid systems requirements and systems descriptions. The systems descriptions contain configurations, fluid inventory data and component lists. In addition, a list of information sources is referenced at the end of each section.

Method and apparatus for chemically altering fluids in continuous flow

DOEpatents

Heath, W.O.; Virden, J.W. Jr.; Richardson, R.L.; Bergsman, T.M.

1993-10-19

The present invention relates to a continuous flow fluid reactor for chemically altering fluids. The reactor operates on standard frequency (50 to 60 Hz) electricity. The fluid reactor contains particles that are energized by the electricity to form a corona throughout the volume of the reactor and subsequently a non-equilibrium plasma that interacts with the fluid. Particles may form a fixed bed or a fluid bed. Electricity may be provided through electrodes or through an inductive coil. Fluids include gases containing exhaust products and organic fuels requiring oxidation. 4 figures.

Method and apparatus for chemically altering fluids in continuous flow

DOEpatents

Heath, William O.; Virden, Jr., Judson W.; Richardson, R. L.; Bergsman, Theresa M.

1993-01-01

The present invention relates to a continuous flow fluid reactor for chemically altering fluids. The reactor operates on standard frequency (50 to 60 Hz) electricity. The fluid reactor contains particles that are energized by the electricity to form a corona throughout the volume of the reactor and subsequently a non-equilibrium plasma that interacts with the fluid. Particles may form a fixed bed or a fluid bed. Electricity may be provided through electrodes or through an inductive coil. Fluids include gases containing exhaust products and organic fuels requiring oxidation.

Safety drain system for fluid reservoir

NASA Technical Reports Server (NTRS)

England, John Dwight (Inventor); Kelley, Anthony R. (Inventor); Cronise, Raymond J. (Inventor)

2012-01-01

A safety drain system includes a plurality of drain sections, each of which defines distinct fluid flow paths. At least a portion of the fluid flow paths commence at a side of the drain section that is in fluid communication with a reservoir's fluid. Each fluid flow path at the side communicating with the reservoir's fluid defines an opening having a smallest dimension not to exceed approximately one centimeter. The drain sections are distributed over at least one surface of the reservoir. A manifold is coupled to the drain sections.

Current Results and Proposed Activities in Microgravity Fluid Dynamics

NASA Technical Reports Server (NTRS)

Polezhaev, V. I.

1996-01-01

The Institute for Problems in Mechanics' Laboratory work in mathematical and physical modelling of fluid mechanics develops models, methods, and software for analysis of fluid flow, instability analysis, direct numerical modelling and semi-empirical models of turbulence, as well as experimental research and verification of these models and their applications in technological fluid dynamics, microgravity fluid mechanics, geophysics, and a number of engineering problems. This paper presents an overview of the results in microgravity fluid dynamics research during the last two years. Nonlinear problems of weakly compressible and compressible fluid flows are discussed.

Fluid mechanics in fluids at rest.

PubMed

Brenner, Howard

2012-07-01

Using readily available experimental thermophoretic particle-velocity data it is shown, contrary to current teachings, that for the case of compressible flows independent dye- and particle-tracer velocity measurements of the local fluid velocity at a point in a flowing fluid do not generally result in the same fluid velocity measure. Rather, tracer-velocity equality holds only for incompressible flows. For compressible fluids, each type of tracer is shown to monitor a fundamentally different fluid velocity, with (i) a dye (or any other such molecular-tagging scheme) measuring the fluid's mass velocity v appearing in the continuity equation and (ii) a small, physicochemically and thermally inert, macroscopic (i.e., non-Brownian), solid particle measuring the fluid's volume velocity v(v). The term "compressibility" as used here includes not only pressure effects on density, but also temperature effects thereon. (For example, owing to a liquid's generally nonzero isobaric coefficient of thermal expansion, nonisothermal liquid flows are to be regarded as compressible despite the general perception of liquids as being incompressible.) Recognition of the fact that two independent fluid velocities, mass- and volume-based, are formally required to model continuum fluid behavior impacts on the foundations of contemporary (monovelocity) fluid mechanics. Included therein are the Navier-Stokes-Fourier equations, which are now seen to apply only to incompressible fluids (a fact well-known, empirically, to experimental gas kineticists). The findings of a difference in tracer velocities heralds the introduction into fluid mechanics of a general bipartite theory of fluid mechanics, bivelocity hydrodynamics [Brenner, Int. J. Eng. Sci. 54, 67 (2012)], differing from conventional hydrodynamics in situations entailing compressible flows and reducing to conventional hydrodynamics when the flow is incompressible, while being applicable to both liquids and gases.

Mixing from below in hydrothermal ore deposits

NASA Astrophysics Data System (ADS)

Bons, Paul D.; Gomez-Rivas, Enrique; Markl, Gregor; Walter, Bejamin

2014-05-01

Unconformity-related hydrothermal ore deposits typically show indications of mixing of two end-member fluids: (a) hot, deep, rock-buffered basement brines and (b) colder fluids derived from the surface or overlying sediments. The hydromechanics of bringing these fluids together from above and below remain unclear. Classical percolative Darcy-flow models are inconsistent with (1) fluid overpressure indicated by fracturing and brecciation, (2) fast fluid flow indicated by thermal disequilibrium, and (3) strong fluid composition variations on the mm-scale, indicated by fluid inclusion analyses (Bons et al. 2012; Fusswinkel et al. 2013). We propose that fluids first descend, sucked down by desiccation reactions in exhumed basement. Oldest fluids reach greatest depths, where long residence times and elevated temperatures allow them the extensively equilibrate with their host rock, reach high salinity and scavenge metals, if present. Youngest fluids can only penetrate to shallower depths and can (partially) retain signatures from their origin, for example high Cl/Br ratios from the dissolution of evaporitic halite horizons. When fluids are released from all levels of the crustal column, these fluids mix during rapid ascent to form hydrothermal ore deposits. Mixing from below provides a viable hydromechanical mechanism to explain the common phenomenon of mixed shallow and deep fluids in hydrothermal ore deposits. Bons, P.D., Elburg, M.A., Gomez-Rivas, E. 2012. A review of the formation of tectonic veins and their microstructures. J. Struct. Geol. doi:10.1016/j.jsg.2012.07.005 Fusswinkel, T., Wagner, T., Wälle, M., Wenzel, T., Heinrich, C.A., Markl, M. 2013. Fluid mixing forms basement-hosted Pb-Zn deposits: Insight from metal and halogen geochemistry of individual fluid inclusions. Geology. doi:10.1130/G34092.1

Oral fluid vs. Urine Analysis to Monitor Synthetic Cannabinoids and Classic Drugs Recent Exposure

PubMed Central

Blandino, Vincent; Wetzel, Jillian; Kim, Jiyoung; Haxhi, Petrit; Curtis, Richard; Concheiro, Marta

2018-01-01

Background Urine is a common biological sample to monitor recent drug exposure, and oral fluid is an alternative matrix of increasing interest in clinical and forensic toxicology. Limited data are available about oral fluid vs. urine drug disposition, especially for synthetic cannabinoids. Objective To compare urine and oral fluid as biological matrices to monitor recent drug exposure among HIV-infected homeless individuals. Methods Seventy matched urine and oral fluid samples were collected from 13 participants. Cannabis, amphetamines, benzodiazepines, cocaine and opiates were analyzed in urine by the enzyme-multiplied-immunoassay-technique and in oral fluid by liquid chromatography tandem mass spectrometry (LC-MSMS). Eleven synthetic cannabinoids were analyzed in urine and in oral fluid by LC-MSMS. Results Five oral fluid samples were positive for AB-FUBINACA. In urine, 4 samples tested positive for synthetic cannabinoids PB-22, 5-Fluoro-PB-22, AB-FUBINACA, and metabolites UR-144 5-pentanoic acid and UR-144 4-hydroxypentyl. In only one case, oral fluid and urine results matched, both specimens being AB-FUBINACA positive. For cannabis, 40 samples tested positive in urine and 30 in oral fluid (85.7% match). For cocaine, 37 urine and 52 oral fluid samples were positive (75.7% match). Twenty-four urine samples were positive for opiates, and 25 in oral fluid (81.4% match). For benzodiazepines, 23 samples were positive in urine and 25 in oral fluid (85.7% match). Conclusion/Discussion These results offer new information about drugs disposition between urine and oral fluid. Oral fluid is a good alternative matrix to urine for monitoring cannabis, cocaine, opiates and benzodiazepines recent use; however, synthetic cannabinoids showed mixed results. PMID:29173162

Oral Fluid vs. Urine Analysis to Monitor Synthetic Cannabinoids and Classic Drugs Recent Exposure.

PubMed

Blandino, Vincent; Wetzel, Jillian; Kim, Jiyoung; Haxhi, Petrit; Curtis, Richard; Concheiro, Marta

2017-01-01

Urine is a common biological sample to monitor recent drug exposure, and oral fluid is an alternative matrix of increasing interest in clinical and forensic toxicology. Limited data are available about oral fluid vs. urine drug disposition, especially for synthetic cannabinoids. To compare urine and oral fluid as biological matrices to monitor recent drug exposure among HIV-infected homeless individuals. Seventy matched urine and oral fluid samples were collected from 13 participants. Cannabis, amphetamines, benzodiazepines, cocaine and opiates were analyzed in urine by the enzyme-multipliedimmunoassay- technique and in oral fluid by liquid chromatography tandem mass spectrometry (LCMSMS). Eleven synthetic cannabinoids were analyzed in urine and in oral fluid by LC-MSMS. Five oral fluid samples were positive for AB-FUBINACA. In urine, 4 samples tested positive for synthetic cannabinoids PB-22, 5-Fluoro-PB-22, AB-FUBINACA, and metabolites UR-144 5-pentanoic acid and UR-144 4-hydroxypentyl. In only one case, oral fluid and urine results matched, both specimens being AB-FUBINACA positive. For cannabis, 40 samples tested positive in urine and 30 in oral fluid (85.7% match). For cocaine, 37 urine and 52 oral fluid samples were positive (75.7% match). Twenty-four urine samples were positive for opiates, and 25 in oral fluid (81.4% match). For benzodiazepines, 23 samples were positive in urine and 25 in oral fluid (85.7% match). These results offer new information about drugs disposition between urine and oral fluid. Oral fluid is a good alternative matrix to urine for monitoring cannabis, cocaine, opiates and benzodiazepines recent use; however, synthetic cannabinoids showed mixed results. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Method and Apparatus for Measuring Fluid Flow

NASA Technical Reports Server (NTRS)

Arndt, G. Dickey (Inventor); Nguyen, Thanh X. (Inventor); Carl, James R. (Inventor)

1997-01-01

Method and apparatus for making measurements on fluids related to their complex permeability are disclosed. A microwave probe is provided for exposure to the fluids. The probe can be non-intrusive or can also be positioned at the location where measurements are to be made. The impedance of the probe is determined. in part. by the complex dielectric constant of the fluids at the probe. A radio frequency signal is transmitted to the probe and the reflected signal is phase and amplitude detected at a rapid rate for the purpose of identifying the fluids. Multiple probes may be selectively positioned to monitor the behavior of the fluids including their flow rate. Fluids may be identified as between two or more different fluids as well as multiple phases of the same fluid based on differences between their complex permittivities.

High-temperature, high-pressure oxygen metering valve

NASA Technical Reports Server (NTRS)

Christianson, Rollin C. (Inventor); Lycou, Peter P. (Inventor); Daniel, James A. (Inventor)

1993-01-01

A control valve includes a body defining a central cavity arranged between a fluid inlet and outwardly-diverging first and second fluid outlets respectively disposed in a common transverse plane. A valve member is arranged in the cavity for rotation between first and second operating positions where a transverse fluid passage through the valve member alternatively communicates the fluid inlet with one or the other of the fluid outlets. To minimize fluid turbulence when the valve member is rotated to an alternate operating position, the fluid passage has a convergent entrance for maintaining the passage in permanent communication with the fluid inlet as well as an oblong exit opening with spaced side walls for enabling the exit opening to temporarily span the first and second fluid outlets as the valve member is turned between its respective operating positions.

Microgravity Fluids for Biology, Workshop

NASA Technical Reports Server (NTRS)

Griffin, DeVon; Kohl, Fred; Massa, Gioia D.; Motil, Brian; Parsons-Wingerter, Patricia; Quincy, Charles; Sato, Kevin; Singh, Bhim; Smith, Jeffrey D.; Wheeler, Raymond M.

2013-01-01

Microgravity Fluids for Biology represents an intersection of biology and fluid physics that present exciting research challenges to the Space Life and Physical Sciences Division. Solving and managing the transport processes and fluid mechanics in physiological and biological systems and processes are essential for future space exploration and colonization of space by humans. Adequate understanding of the underlying fluid physics and transport mechanisms will provide new, necessary insights and technologies for analyzing and designing biological systems critical to NASAs mission. To enable this mission, the fluid physics discipline needs to work to enhance the understanding of the influence of gravity on the scales and types of fluids (i.e., non-Newtonian) important to biology and life sciences. In turn, biomimetic, bio-inspired and synthetic biology applications based on physiology and biology can enrich the fluid mechanics and transport phenomena capabilities of the microgravity fluid physics community.

Device and method for measuring multi-phase fluid flow and density of fluid in a conduit having a gradual bend

DOEpatents

Ortiz, Marcos German; Boucher, Timothy J.

1998-01-01

A system for measuring fluid flow in a conduit having a gradual bend or arc, and a straight section. The system includes pressure transducers, one or more disposed in the conduit on the outside of the arc, and one disposed in the conduit in a straight section thereof. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow.

Heat exchanger and related methods

DOEpatents

Turner, Terry D.; McKellar, Michael G.

2015-12-22

Heat exchangers include a housing having an inlet and an outlet and forming a portion of a transition chamber. A heating member may form another portion of the transition chamber. The heating member includes a first end having a first opening and a second end having a second opening larger than the first opening. Methods of conveying a fluid include supplying a first fluid into a transition chamber of a heat exchanger, supplying a second fluid into the transition chamber, and altering a state of a portion of the first fluid with the second fluid. Methods of sublimating solid particles include conveying a first fluid comprising a material in a solid state into a transition chamber, heating the material to a gaseous state by directing a second fluid through a heating member and mixing the first fluid and the second fluid.

2013 AAHA/AAFP fluid therapy guidelines for dogs and cats.

PubMed

Davis, Harold; Jensen, Tracey; Johnson, Anthony; Knowles, Pamela; Meyer, Robert; Rucinsky, Renee; Shafford, Heidi

2013-01-01

Fluid therapy is important for many medical conditions in veterinary patients. The assessment of patient history, chief complaint, physical exam findings, and indicated additional testing will determine the need for fluid therapy. Fluid selection is dictated by the patient's needs, including volume, rate, fluid composition required, and location the fluid is needed (e.g., interstitial versus intravascular). Therapy must be individualized, tailored to each patient, and constantly re-evaluated and reformulated according to changes in status. Needs may vary according to the existence of either acute or chronic conditions, patient pathology (e.g., acid-base, oncotic, electrolyte abnormalities), and comorbid conditions. All patients should be assessed for three types of fluid disturbances: changes in volume, changes in content, and/or changes in distribution. The goals of these guidelines are to assist the clinician in prioritizing goals, selecting appropriate fluids and rates of administration, and assessing patient response to therapy. These guidelines provide recommendations for fluid administration for anesthetized patients and patients with fluid disturbances.

Dynamic characteristics of Non Newtonian fluid Squeeze film damper

NASA Astrophysics Data System (ADS)

Palaksha, C. P.; Shivaprakash, S.; Jagadish, H. P.

2016-09-01

The fluids which do not follow linear relationship between rate of strain and shear stress are termed as non-Newtonian fluid. The non-Newtonian fluids are usually categorized as those in which shear stress depends on the rates of shear only, fluids for which relation between shear stress and rate of shear depends on time and the visco inelastic fluids which possess both elastic and viscous properties. It is quite difficult to provide a single constitutive relation that can be used to define a non-Newtonian fluid due to a great diversity found in its physical structure. Non-Newtonian fluids can present a complex rheological behaviour involving shear-thinning, viscoelastic or thixotropic effects. The rheological characterization of complex fluids is an important issue in many areas. The paper analyses the damping and stiffness characteristics of non-Newtonian fluids (waxy crude oil) used in squeeze film dampers using the available literature for viscosity characterization. Damping and stiffness characteristic will be evaluated as a function of shear strain rate, temperature and percentage wax concentration etc.

Theoretical fluid dynamics

NASA Astrophysics Data System (ADS)

Shivamoggi, B. K.

This book is concerned with a discussion of the dynamical behavior of a fluid, and is addressed primarily to graduate students and researchers in theoretical physics and applied mathematics. A review of basic concepts and equations of fluid dynamics is presented, taking into account a fluid model of systems, the objective of fluid dynamics, the fluid state, description of the flow field, volume forces and surface forces, relative motion near a point, stress-strain relation, equations of fluid flows, surface tension, and a program for analysis of the governing equations. The dynamics of incompressible fluid flows is considered along with the dynamics of compressible fluid flows, the dynamics of viscous fluid flows, hydrodynamic stability, and dynamics of turbulence. Attention is given to the complex-variable method, three-dimensional irrotational flows, vortex flows, rotating flows, water waves, applications to aerodynamics, shock waves, potential flows, the hodograph method, flows at low and high Reynolds numbers, the Jeffrey-Hamel flow, and the capillary instability of a liquid jet.

Fluid Therapy: Options and Rational Selection.

PubMed

Byers, Christopher G

2017-03-01

Administration of appropriate types and volumes of parenteral fluids is of paramount importance when treating sick and debilitated patients, especially those fighting critical illness. Fluid selection and accurate calculations must be performed logically and accurately to maximize positive outcomes. Knowledge of fluid types, as well as the complex relationship of the body's fluid compartments, helps clinicians develop rational fluid therapy plans for their patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluation of stroke volume variation obtained by arterial pulse contour analysis to predict fluid responsiveness intraoperatively.

PubMed

Lahner, D; Kabon, B; Marschalek, C; Chiari, A; Pestel, G; Kaider, A; Fleischmann, E; Hetz, H

2009-09-01

Fluid management guided by oesophageal Doppler monitor has been reported to improve perioperative outcome. Stroke volume variation (SVV) is considered a reliable clinical predictor of fluid responsiveness. Consequently, the aim of the present trial was to evaluate the accuracy of SVV determined by arterial pulse contour (APCO) analysis, using the FloTrac/Vigileo system, to predict fluid responsiveness as measured by the oesophageal Doppler. Patients undergoing major abdominal surgery received intraoperative fluid management guided by oesophageal Doppler monitoring. Fluid boluses of 250 ml each were administered in case of a decrease in corrected flow time (FTc) to <350 ms. Patients were connected to a monitoring device, obtaining SVV by APCO. Haemodynamic variables were recorded before and after fluid bolus application. Fluid responsiveness was defined as an increase in stroke volume index >10%. The ability of SVV to predict fluid responsiveness was assessed by calculation of the area under the receiver operating characteristic (ROC) curve. Twenty patients received 67 fluid boluses. Fifty-two of the 67 fluid boluses administered resulted in fluid responsiveness. SVV achieved an area under the ROC curve of 0.512 [confidence interval (CI) 0.32-0.70]. A cut-off point for fluid responsiveness was found for SVV > or =8.5% (sensitivity: 77%; specificity: 43%; positive predictive value: 84%; and negative predictive value: 33%). This prospective, interventional observer-blinded study demonstrates that SVV obtained by APCO, using the FloTrac/Vigileo system, is not a reliable predictor of fluid responsiveness in the setting of major abdominal surgery.

On the role of fluids in stick-slip dynamics of saturated granular fault gouge using a coupled computational fluid dynamics-discrete element approach: STICK-SLIP IN SATURATED FAULT GOUGE

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

Dorostkar, Omid; Guyer, Robert A.; Johnson, Paul A.

The presence of fault gouge has considerable influence on slip properties of tectonic faults and the physics of earthquake rupture. The presence of fluids within faults also plays a significant role in faulting and earthquake processes. In this study, we present 3-D discrete element simulations of dry and fluid-saturated granular fault gouge and analyze the effect of fluids on stick-slip behavior. Fluid flow is modeled using computational fluid dynamics based on the Navier-Stokes equations for an incompressible fluid and modified to take into account the presence of particles. Analysis of a long time train of slip events shows that themore » (1) drop in shear stress, (2) compaction of granular layer, and (3) the kinetic energy release during slip all increase in magnitude in the presence of an incompressible fluid, compared to dry conditions. We also observe that on average, the recurrence interval between slip events is longer for fluid-saturated granular fault gouge compared to the dry case. This observation is consistent with the occurrence of larger events in the presence of fluid. It is found that the increase in kinetic energy during slip events for saturated conditions can be attributed to the increased fluid flow during slip. Finally, our observations emphasize the important role that fluid flow and fluid-particle interactions play in tectonic fault zones and show in particular how discrete element method (DEM) models can help understand the hydromechanical processes that dictate fault slip.« less

Radiation receiver

DOEpatents

Hunt, A.J.

1983-09-13

The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles. 5 figs.

Radiation receiver

DOEpatents

Hunt, Arlon J.

1983-01-01

The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

Vascular leakage in dengue--clinical spectrum and influence of parenteral fluid therapy.

PubMed

Rosenberger, Kerstin D; Lum, Lucy; Alexander, Neal; Junghanss, Thomas; Wills, Bridget; Jaenisch, Thomas

2016-03-01

Clinical management of dengue relies on careful monitoring of fluid balance combined with judicious intravenous (IV) fluid therapy. However, in patients with significant vascular leakage, IV fluids may aggravate serosal fluid accumulation and result in respiratory distress. Trained physicians followed suspected dengue cases prospectively at seven hospitals across Asia and Latin America, using a comprehensive case report form that included daily clinical assessment and detailed documentation of parenteral fluid therapy. Applying Cox regression, we evaluated risk factors for the development of shock or respiratory distress with fluid accumulation. Most confirmed dengue patients (1524/1734, 88%) never experienced dengue shock syndrome (DSS). Among those with DSS, 176/210 (84%) had fluid accumulation, and in the majority (83%), this was detectable clinically. Among all cases with clinically detectable fluid accumulation, 179/447 (40%) were diagnosed with shock or respiratory distress. The risk for respiratory distress with fluid accumulation increased significantly as the infused volume over the preceding 24 h increased (hazard ratio 1.18 per 10 ml/kg increase; P < 0.001). Longer duration of IV therapy, use of a fluid bolus in the preceding 24 h, female gender and poor nutrition also constituted independent risk factors. Shock and respiratory distress are relatively rare manifestations of dengue, but some evidence of fluid accumulation is seen in around 50% of cases. IV fluids play a crucial role in management, but they must be administered with caution. Clinically and/or radiologically detectable fluid accumulations have potential as intermediate severity endpoints for therapeutic intervention trials and/or pathogenesis studies. © 2016 John Wiley & Sons Ltd.

On the role of fluids in stick-slip dynamics of saturated granular fault gouge using a coupled computational fluid dynamics-discrete element approach: STICK-SLIP IN SATURATED FAULT GOUGE

DOE PAGES

Dorostkar, Omid; Guyer, Robert A.; Johnson, Paul A.; ...

2017-05-01

The presence of fault gouge has considerable influence on slip properties of tectonic faults and the physics of earthquake rupture. The presence of fluids within faults also plays a significant role in faulting and earthquake processes. In this study, we present 3-D discrete element simulations of dry and fluid-saturated granular fault gouge and analyze the effect of fluids on stick-slip behavior. Fluid flow is modeled using computational fluid dynamics based on the Navier-Stokes equations for an incompressible fluid and modified to take into account the presence of particles. Analysis of a long time train of slip events shows that themore » (1) drop in shear stress, (2) compaction of granular layer, and (3) the kinetic energy release during slip all increase in magnitude in the presence of an incompressible fluid, compared to dry conditions. We also observe that on average, the recurrence interval between slip events is longer for fluid-saturated granular fault gouge compared to the dry case. This observation is consistent with the occurrence of larger events in the presence of fluid. It is found that the increase in kinetic energy during slip events for saturated conditions can be attributed to the increased fluid flow during slip. Finally, our observations emphasize the important role that fluid flow and fluid-particle interactions play in tectonic fault zones and show in particular how discrete element method (DEM) models can help understand the hydromechanical processes that dictate fault slip.« less

Radiant energy collection and conversion apparatus and method

DOEpatents

Hunt, Arlon J.

1982-01-01

The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

Radiant energy collection and conversion apparatus and method

DOEpatents

Hunt, A.J.

The apparatus for collecting radiant energy and converting to alternate energy forms includes a housing having an interior space and a radiation transparent window allowing solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past the window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

A Novel CO2-Responsive Viscoelastic Amphiphilic Surfactant Fluid for Fracking in Enhanced Oil/Gas Recovery

NASA Astrophysics Data System (ADS)

Zhong, L.; Wu, X.; Dai, C.

2017-12-01

Over the past decade, the rapid rise of unconventional shale gas and tight sandstone oil development through horizontal drilling and high volume hydraulic fracturing has expanded the extraction of hydrocarbon resources. Hydraulic fracturing fluids play very important roles in enhanced oil/gas recovery. However, damage to the reservoir rock and environmental contamination caused by hydraulic fracturing flowback fluids has raised serious concerns. The development of reservoir rock friendly and environmental benign fracturing fluids is in immediate demand. Studies to improve properties of hydraulic fracturing fluids have found that viscoelastic surfactant (VES) fracturing fluid can increase the productivity of gas/oil and be efficiently extracted after fracturing. Compared to conventional polymer fracturing fluid, VES fracturing fluid has many advantages, such as few components, easy preparation, good proppant transport capacity, low damage to cracks and formations, and environment friendly. In this work, we are developing a novel CO2-responsive VES fracking fluid that can readily be reused. This fluid has a gelling-breaking process that can be easily controlled by the presence of CO2 and its pressure. We synthesized erucamidopropyl dimethylamine (EA) as a thickening agent for hydraulic fracturing fluid. The influence of temperature, presence of CO2 and pressure on the viscoelastic behavior of this fluid was then investigated through rheological measurements. The fracturing fluid performance and recycle property were lastly studied using core flooding tests. We expect this fluid finds applications not only in enhanced oil/gas recovery, but also in areas such as controlling groundwater pollution and microfluidics.

An immersed boundary method for two-phase fluids and gels and the swimming of Caenorhabditis elegans through viscoelastic fluids

PubMed Central

Lee, Pilhwa; Wolgemuth, Charles W.

2016-01-01

The swimming of microorganisms typically involves the undulation or rotation of thin, filamentary objects in a fluid or other medium. Swimming in Newtonian fluids has been examined extensively, and only recently have investigations into microorganism swimming through non-Newtonian fluids and gels been explored. The equations that govern these more complex media are often nonlinear and require computational algorithms to study moderate to large amplitude motions of the swimmer. Here, we develop an immersed boundary method for handling fluid-structure interactions in a general two-phase medium, where one phase is a Newtonian fluid and the other phase is viscoelastic (e.g., a polymer melt or network). We use this algorithm to investigate the swimming of an undulating, filamentary swimmer in 2D (i.e., a sheet). A novel aspect of our method is that it allows one to specify how forces produced by the swimmer are distributed between the two phases of the fluid. The algorithm is validated by comparing theoretical predictions for small amplitude swimming in gels and viscoelastic fluids. We show how the swimming velocity depends on material parameters of the fluid and the interaction between the fluid and swimmer. In addition, we simulate the swimming of Caenorhabditis elegans in viscoelastic fluids and find good agreement between the swimming speeds and fluid flows in our simulations and previous experimental measurements. These results suggest that our methodology provides an accurate means for exploring the physics of swimming through non-Newtonian fluids and gels. PMID:26858520

Bioimpedance-Guided Fluid Management in Hemodialysis Patients

PubMed Central

Arias-Guillén, Marta; Wabel, Peter; Fontseré, Néstor; Carrera, Montserrat; Campistol, José Maria; Maduell, Francisco

2013-01-01

Summary Background and objectives Achieving and maintaining optimal fluid status remains a major challenge in hemodialysis therapy. The aim of this interventional study was to assess the feasibility and clinical consequences of active fluid management guided by bioimpedance spectroscopy in chronic hemodialysis patients. Design, setting, participants, & measurements Fluid status was optimized prospectively in 55 chronic hemodialysis patients over 3 months (November 2011 to February 2012). Predialysis fluid overload was measured weekly using the Fresenius Body Composition Monitor. Time-averaged fluid overload was calculated as the average between pre- and postdialysis fluid overload. The study aimed to bring the time-averaged fluid overload of all patients into a target range of 0.5±0.75 L within the first month and maintain optimal fluid status until study end. Postweight was adjusted weekly according to a predefined protocol. Results Time-averaged fluid overload in the complete study cohort was 0.9±1.6 L at baseline and 0.6±1.1 L at study end. Time-averaged fluid overload decreased by −1.20±1.32 L (P<0.01) in the fluid-overloaded group (n=17), remained unchanged in the normovolemic group (n=26, P=0.59), and increased by 0.59±0.76 L (P=0.02) in the dehydrated group (n=12). Every 1 L change in fluid overload was accompanied by a 9.9 mmHg/L change in predialysis systolic BP (r=0.55, P<0.001). At study end, 76% of all patients were either on time-averaged fluid overload target or at least closer to target than at study start. The number of intradialytic symptoms did not change significantly in any of the subgroups. Conclusions Active fluid management guided by bioimpedance spectroscopy was associated with an improvement in overall fluid status and BP. PMID:23949235

What is the impact of the fluid challenge technique on diagnosis of fluid responsiveness? A systematic review and meta-analysis.

PubMed

Toscani, Laura; Aya, Hollmann D; Antonakaki, Dimitra; Bastoni, Davide; Watson, Ximena; Arulkumaran, Nish; Rhodes, Andrew; Cecconi, Maurizio

2017-08-04

The fluid challenge is considered the gold standard for diagnosis of fluid responsiveness. The objective of this study was to describe the fluid challenge techniques reported in fluid responsiveness studies and to assess the difference in the proportion of 'responders,' (PR) depending on the type of fluid, volume, duration of infusion and timing of assessment. Searches of MEDLINE and Embase were performed for studies using the fluid challenge as a test of cardiac preload with a description of the technique, a reported definition of fluid responsiveness and PR. The primary outcome was the mean PR, depending on volume of fluid, type of fluids, rate of infusion and time of assessment. A total of 85 studies (3601 patients) were included in the analysis. The PR were 54.4% (95% CI 46.9-62.7) where <500 ml was administered, 57.2% (95% CI 52.9-61.0) where 500 ml was administered and 60.5% (95% CI 35.9-79.2) where >500 ml was administered (p = 0.71). The PR was not affected by type of fluid. The PR was similar among patients administered a fluid challenge for <15 minutes (59.2%, 95% CI 54.2-64.1) and for 15-30 minutes (57.7%, 95% CI 52.4-62.4, p = 1). Where the infusion time was ≥30 minutes, there was a lower PR of 49.9% (95% CI 45.6-54, p = 0.04). Response was assessed at the end of fluid challenge, between 1 and 10 minutes, and >10 minutes after the fluid challenge. The proportions of responders were 53.9%, 57.7% and 52.3%, respectively (p = 0.47). The PR decreases with a long infusion time. A standard technique for fluid challenge is desirable.

14 CFR 23.863 - Flammable fluid fire protection.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Flammable fluid fire protection. 23.863... Construction Fire Protection § 23.863 Flammable fluid fire protection. (a) In each area where flammable fluids... fluids, shutting down equipment, fireproof containment, or use of extinguishing agents. (5) Ability of...

14 CFR 23.863 - Flammable fluid fire protection.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Flammable fluid fire protection. 23.863... Construction Fire Protection § 23.863 Flammable fluid fire protection. (a) In each area where flammable fluids... fluids, shutting down equipment, fireproof containment, or use of extinguishing agents. (5) Ability of...

14 CFR 23.863 - Flammable fluid fire protection.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Flammable fluid fire protection. 23.863... Construction Fire Protection § 23.863 Flammable fluid fire protection. (a) In each area where flammable fluids... fluids, shutting down equipment, fireproof containment, or use of extinguishing agents. (5) Ability of...

14 CFR 23.863 - Flammable fluid fire protection.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Flammable fluid fire protection. 23.863... Construction Fire Protection § 23.863 Flammable fluid fire protection. (a) In each area where flammable fluids... fluids, shutting down equipment, fireproof containment, or use of extinguishing agents. (5) Ability of...

Capillary interconnect device

DOEpatents

Renzi, Ronald F

2013-11-19

An interconnecting device for connecting a plurality of first fluid-bearing conduits to a corresponding plurality of second fluid-bearing conduits thereby providing fluid communication between the first fluid-bearing conduits and the second fluid-bearing conduits. The device includes a manifold and one or two ferrule plates that are held by compressive axial forces.

Compressor bleed cooling fluid feed system

DOEpatents

Donahoo, Eric E; Ross, Christopher W

2014-11-25

A compressor bleed cooling fluid feed system for a turbine engine for directing cooling fluids from a compressor to a turbine airfoil cooling system to supply cooling fluids to one or more airfoils of a rotor assembly is disclosed. The compressor bleed cooling fluid feed system may enable cooling fluids to be exhausted from a compressor exhaust plenum through a downstream compressor bleed collection chamber and into the turbine airfoil cooling system. As such, the suction created in the compressor exhaust plenum mitigates boundary layer growth along the inner surface while providing flow of cooling fluids to the turbine airfoils.

Hormonal regulation of fluid and electrolyte metabolism during periods of headward fluid shifts

NASA Technical Reports Server (NTRS)

Keil, Lanny C.; Severs, W. B.; Thrasher, T.; Ramsay, D. J.

1991-01-01

In the broadest sense, this project evaluates how spaceflight induced shifts of blood and interstitial fluids into the thorax affect regulation by the central nervous system (CNS) of fluid-electrolyte hormone secretion. Specifically, it focuses on the role of hormones related to salt/water balance and their potential function in the control of intracranial pressure and cerebrospinal fluid (CSF) composition. Fluid-electrolyte status during spaceflight gradually equilibrates, with a reduction in all body fluid compartments. Related to this is the cardiovascular deconditioning of spaceflight which is manifested upon return to earth as orthostatic intolerance.

Neonatal fluid management.

PubMed

Murat, Isabelle; Humblot, Alexis; Girault, Laure; Piana, Federica

2010-09-01

Perioperative fluid management in paediatrics has been the subject of many controversies in recent years, but fluid management in the neonatal period has not been considered in most reviews and guidelines. The literature regarding neonatal fluid management mainly appears in the paediatric textbooks and few recent data are available, except for resuscitation and fluid loading during shock and major surgery. In the context of anaesthesia, many neonates requiring surgery within the first month of life have organ malformation and/or dysfunction. This article aims at reviewing basic physiological considerations important for neonatal fluid management and mainly focusses on fluid maintenance and replacement during surgery.

Selectivity enhancement in photoacoustic gas analysis via phase-sensitive detection at high modulation frequency

NASA Technical Reports Server (NTRS)

Kosterev, Anatoliy (Inventor)

2010-01-01

A method for detecting a target fluid in a fluid sample comprising a first fluid and the target fluid using photoacoustic spectroscopy (PAS), comprises a) providing a light source configured to introduce an optical signal having at least one wavelength into the fluid sample; b) modulating the optical signal at a desired modulation frequency such that the optical signal generates an acoustic signal in the fluid sample; c) measuring the acoustic signal in a resonant acoustic detector; and d) using the phase of the acoustic signal to detect the presence of the target fluid.

Thermo-Physical Properties of Intermediate Temperature Heat Pipe Fluids

NASA Technical Reports Server (NTRS)

Beach, Duane E. (Technical Monitor); Devarakonda, Angirasa; Anderson, William G.

2005-01-01

Heat pipes are among the most promising technologies for space radiator systems. The paper reports further evaluation of potential heat pipe fluids in the intermediate temperature range of 400 to 700 K in continuation of two recent reports. More thermo-physical property data are examined. Organic, inorganic, and elemental substances are considered. The evaluation of surface tension and other fluid properties are examined. Halides are evaluated as potential heat pipe fluids. Reliable data are not available for all fluids and further database development is necessary. Many of the fluids considered are promising candidates as heat pipe fluids. Water is promising as a heat pipe fluid up to 500 to 550 K. Life test data for thermo-chemical compatibility are almost non-existent.

Thermo-Physical Properties of Intermediate Temperature Heat Pipe Fluids

NASA Technical Reports Server (NTRS)

Devarakonda, Angirasa; Anderson, William G.

2004-01-01

Heat pipes are among the most promising technologies for space radiator systems. The paper reports further evaluation of potential heat pipe fluids in the intermediate temperature range of 400 to 700 K in continuation of two recent reports. More thermo-physical property data are examined. Organic, inorganic and elemental substances are considered. The evaluation of surface tension and other fluid properties are examined. Halides are evaluated as potential heat pipe fluids. Reliable data are not available for all fluids and further database development in necessary. Many of the fluids considered are promising candidates as heat pipe fluids. Water is promising as a heat pipe fluid up to 500-550 K. Life test data for thermo-chemical compatibility are almost non-existent.

Solution mining systems and methods for treating hydrocarbon containing formations

DOEpatents

Vinegar, Harold J [Bellaire, TX; de Rouffignac, Eric Pierre [Rijswijk, NL; Schoeling, Lanny Gene [Katy, TX

2009-07-14

A method for treating an oil shale formation comprising nahcolite is disclosed. The method includes providing a first fluid to a portion of the formation through at least two injection wells. A second fluid is produced from the portion through at least one injection well until at least two injection wells are interconnected such that fluid can flow between the two injection wells. The second fluid includes at least some nahcolite dissolved in the first fluid. The first fluid is injected through one of the interconnected injection wells. The second fluid is produced from at least one of the interconnected injection wells. Heat is provided from one or more heaters to the formation to heat the formation. Hydrocarbon fluids are produced from the formation.

Fluid Retention and Rostral Fluid Shift in Sleep-Disordered Breathing.

PubMed

Kasai, Takatoshi

2016-01-01

Sleep-disordered breathing (SDB) is common and adversely affects cardiovascular morbidity and mortality. Despite multifactorial pathogenesis, SDB is prevalent in patients with fluid retention disorders, such as drug-resistant hypertension, end-stage renal disease, and heart failure, suggesting that fluid retention may play a role in the pathogenesis of SDB. During the day, fluid is likely to accumulate in the legs, and upon lying down at night is displaced from the legs. Many data suggest that some of this fluid displaced from the legs may redistribute to the upper body and predispose to SDB. This review article will highlight evidence for a relationship between SDB and fluid retention or rostral fluid shift, and discuss mechanisms that link them.

CMC blade with pressurized internal cavity for erosion control

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

Garcia-Crespo, Andres; Goike, Jerome Walter

A ceramic matrix composite blade for use in a gas turbine engine having an airfoil with leading and trailing edges and pressure and suction side surfaces, a blade shank secured to the lower end of each airfoil, one or more interior fluid cavities within the airfoil having inlet flow passages at the lower end which are in fluid communication with the blade shank, one or more passageways in the blade shank corresponding to each one of the interior fluid cavities and a fluid pump (or compressor) that provides pressurized fluid (nominally cool, dry air) to each one of the interiormore » fluid cavities in each airfoil. The fluid (e.g., air) is sufficient in pressure and volume to maintain a minimum fluid flow to each of the interior fluid cavities in the event of a breach due to foreign object damage.« less

Methods of conveying fluids and methods of sublimating solid particles

DOEpatents

Turner, Terry D; Wilding, Bruce M

2013-10-01

A heat exchanger and associated methods for sublimating solid particles therein, for conveying fluids therethrough, or both. The heat exchanger includes a chamber and a porous member having a porous wall having pores in communication with the chamber and with an interior of the porous member. A first fluid is conveyed into the porous member while a second fluid is conveyed into the porous member through the porous wall. The second fluid may form a positive flow boundary layer along the porous wall to reduce or eliminate substantial contact between the first fluid and the interior of the porous wall. The combined first and second fluids are conveyed out of the porous member. Additionally, the first fluid and the second fluid may each be conveyed into the porous member at different temperatures and may exit the porous member at substantially the same temperature.

An overview on current fluid-inclusion research and applications

USGS Publications Warehouse

Chi, G.; Chou, I.-Ming; Lu, H.-Z.

2003-01-01

This paper provides an overview of some of the more important developments in fluid-inclusion research and applications in recent years, including fluid-inclusion petrography, PVTX studies, and analytical techniques. In fluid-inclusion petrography, the introduction of the concept of 'fluid-inclusion assemblage' has been a major advance. In PVTX studies, the use of synthetic fluid inclusions and hydrothermal diamond-anvil cells has greatly contributed to the characterization of the phase behaviour of geologically relevant fluid systems. Various analytical methods are being developed and refined rapidly, with the Laser-Raman and LA-ICP-MS techniques being particularly useful for volatile and solute analyses, respectively. Ore deposit research has been and will continue to be the main field of application of fluid inclusions. However, fluid inclusions have been increasingly applied to other fields of earth science, especially in petroleum geology and the study of magmatic and earth interior processes.

Fluid sampling system for a nuclear reactor

DOEpatents

Lau, Louis K.; Alper, Naum I.

1994-01-01

A system of extracting fluid samples, either liquid or gas, from the interior of a nuclear reactor containment utilizes a jet pump. To extract the sample fluid, a nonradioactive motive fluid is forced through the inlet and discharge ports of a jet pump located outside the containment, creating a suction that draws the sample fluid from the containment through a sample conduit connected to the pump suction port. The mixture of motive fluid and sample fluid is discharged through a return conduit to the interior of the containment. The jet pump and means for removing a portion of the sample fluid from the sample conduit can be located in a shielded sample grab station located next to the containment. A non-nuclear grade active pump can be located outside the grab sampling station and the containment to pump the nonradioactive motive fluid through the jet pump.

Brief report: Adherence to fluid recommendations in children receiving treatment for retentive encopresis.

PubMed

Kuhl, Elizabeth S; Felt, Barbara T; Patton, Susana R

2009-01-01

Limited data are available regarding whether children being treated for retentive encopresis are adherent to recommendations to increase their daily fluid intake. The purpose of this study was to examine fluid adherence in children who received treatment for retentive encopresis. A retrospective chart review was performed using diet diary data for 26 children (ages 3-12) who completed a group behavioral intervention for retentive encopresis. Mean daily intake of clear fluid increased significantly during treatment and children relied primarily on water and juice to make this dietary change. However, adherence rates to clear fluid goals were <50%. Children's increased clear fluid intake did not equate to high fluid adherence. Children's high juice consumption is concerning as it could place them at risk for other negative health consequences. Future research should examine whether enhanced fluid education and use of behavior change strategies yield higher fluid adherence.

Viscous fingering with partially miscible fluids

NASA Astrophysics Data System (ADS)

Fu, Xiaojing; Cueto-Felgueroso, Luis; Juanes, Ruben

2017-10-01

Viscous fingering—the fluid-mechanical instability that takes place when a low-viscosity fluid displaces a high-viscosity fluid—has traditionally been studied under either fully miscible or fully immiscible fluid systems. Here we study the impact of partial miscibility (a common occurrence in practice) on the fingering dynamics. Through a careful design of the thermodynamic free energy of a binary mixture, we develop a phase-field model of fluid-fluid displacements in a Hele-Shaw cell for the general case in which the two fluids have limited (but nonzero) solubility into one another. We show, by means of high-resolution numerical simulations, that partial miscibility exerts a powerful control on the degree of fingering: fluid dissolution hinders fingering while fluid exsolution enhances fingering. We also show that, as a result of the interplay between compositional exchange and the hydrodynamic pattern-forming process, stronger fingering promotes the system to approach thermodynamic equilibrium more quickly.

Multiple source heat pump

DOEpatents

Ecker, Amir L.

1983-01-01

A heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating a fluid in heat exchange relationship with a refrigerant fluid, at least three refrigerant heat exchangers, one for effecting heat exchange with the fluid, a second for effecting heat exchange with a heat exchange fluid, and a third for effecting heat exchange with ambient air; a compressor for compressing the refrigerant; at least one throttling valve connected at the inlet side of a heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circuit and pump for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and directional flow of refrigerant therethrough for selecting a particular mode of operation. Also disclosed are a variety of embodiments, modes of operation, and schematics therefor.

Gas turbine engine exhaust diffuser including circumferential vane

DOEpatents

Orosa, John A.; Matys, Pawel

2015-05-19

A flow passage defined between an inner and an outer boundary for guiding a fluid flow in an axial direction. A flow control vane is supported at a radial location between the inner and outer boundaries. A fluid discharge opening is provided for discharging a flow of the compressed fluid from a trailing edge of the vane, and a fluid control surface is provided adjacent to the fluid discharge opening and extends in the axial direction at the trailing edge of the vane. The fluid control surface has a curved trailing edge forming a Coanda surface. The fluid discharge opening is selectively provided with a compressed fluid to produce a Coanda effect along the control surface. The Coanda effect has a component in the radial direction effecting a turning of the fluid flow in the flow path radially inward or outward toward one of the inner and outer boundaries.

Electric fluid pump

DOEpatents

Van Dam, Jeremy Daniel; Turnquist, Norman Arnold; Raminosoa, Tsarafidy; Shah, Manoj Ramprasad; Shen, Xiaochun

2015-09-29

An electric machine is presented. The electric machine includes a hollow rotor; and a stator disposed within the hollow rotor, the stator defining a flow channel. The hollow rotor includes a first end portion defining a fluid inlet, a second end portion defining a fluid outlet; the fluid inlet, the fluid outlet, and the flow channel of the stator being configured to allow passage of a fluid from the fluid inlet to the fluid outlet via the flow channel; and wherein the hollow rotor is characterized by a largest cross-sectional area of hollow rotor, and wherein the flow channel is characterized by a smallest cross-sectional area of the flow channel, wherein the smallest cross-sectional area of the flow channel is at least about 25% of the largest cross-sectional area of the hollow rotor. An electric fluid pump and a power generation system are also presented.

Fluid sampling system for a nuclear reactor

DOEpatents

Lau, L.K.; Alper, N.I.

1994-11-22

A system of extracting fluid samples, either liquid or gas, from the interior of a nuclear reactor containment utilizes a jet pump. To extract the sample fluid, a nonradioactive motive fluid is forced through the inlet and discharge ports of a jet pump located outside the containment, creating a suction that draws the sample fluid from the containment through a sample conduit connected to the pump suction port. The mixture of motive fluid and sample fluid is discharged through a return conduit to the interior of the containment. The jet pump and means for removing a portion of the sample fluid from the sample conduit can be located in a shielded sample grab station located next to the containment. A non-nuclear grade active pump can be located outside the grab sampling station and the containment to pump the nonradioactive motive fluid through the jet pump. 1 fig.

Curved film cooling admission tube

NASA Astrophysics Data System (ADS)

Graham, R. W.; Papell, S. S.

1980-10-01

Effective film cooling to protect a wall surface from a hot fluid which impinges on or flows along the surface is provided. A film of cooling fluid having increased area is provided by changing the direction of a stream of cooling fluid through an angle of from 135 deg. to 165 deg. before injecting it through the wall into the hot flowing gas. The 1, cooling fluid is injected from an orifice through a wall into a hot flowing gas at an angle to form a cooling fluid film. Cooling fluid is supplied to the orifice from a cooling fluid source via a turbulence control passageway having a curved portion between two straight portions. The angle through which the direction of the cooling fluid is turned results in less mixing of the cooling fluid with the hot gas, thereby substantially increasing the length of the film in a downstream direction.

Curved film cooling admission tube

NASA Technical Reports Server (NTRS)

Graham, R. W.; Papell, S. S. (Inventor)

1980-01-01

Effective film cooling to protect a wall surface from a hot fluid which impinges on or flows along the surface is provided. A film of cooling fluid having increased area is provided by changing the direction of a stream of cooling fluid through an angle of from 135 deg. to 165 deg. before injecting it through the wall into the hot flowing gas. The 1, cooling fluid is injected from an orifice through a wall into a hot flowing gas at an angle to form a cooling fluid film. Cooling fluid is supplied to the orifice from a cooling fluid source via a turbulence control passageway having a curved portion between two straight portions. The angle through which the direction of the cooling fluid is turned results in less mixing of the cooling fluid with the hot gas, thereby substantially increasing the length of the film in a downstream direction.

Precision Fluid Management in Continuous Renal Replacement Therapy.

PubMed

Murugan, Raghavan; Hoste, Eric; Mehta, Ravindra L; Samoni, Sara; Ding, Xiaoqiang; Rosner, Mitchell H; Kellum, John A; Ronco, Claudio

2016-01-01

Fluid management during continuous renal replacement therapy (CRRT) in critically ill patients is a dynamic process that encompasses 3 inter-related goals: maintenance of the patency of the CRRT circuit, maintenance of plasma electrolyte and acid-base homeostasis and regulation of patient fluid balance. In this article, we report the consensus recommendations of the 2016 Acute Disease Quality Initiative XVII conference on 'Precision Fluid Management in CRRT'. We discuss the principles of fluid management, describe various prescription methods to achieve circuit integrity and introduce the concept of integrated fluid balance for tailoring fluid balance to the needs of the individual patient. We suggest that these recommendations could serve to develop the best clinical practice and standards of care for fluid management in patients undergoing CRRT. Finally, we identify and highlight areas of uncertainty in fluid management and set an agenda for future research. © 2016 S. Karger AG, Basel.

On the micromechanics of slip events in sheared, fluid-saturated fault gouge

NASA Astrophysics Data System (ADS)

Dorostkar, Omid; Guyer, Robert A.; Johnson, Paul A.; Marone, Chris; Carmeliet, Jan

2017-06-01

We used a three-dimensional discrete element method coupled with computational fluid dynamics to study the poromechanical properties of dry and fluid-saturated granular fault gouge. The granular layer was sheared under dry conditions to establish a steady state condition of stick-slip dynamic failure, and then fluid was introduced to study its effect on subsequent failure events. The fluid-saturated case showed increased stick-slip recurrence time and larger slip events compared to the dry case. Particle motion induces fluid flow with local pressure variation, which in turn leads to high particle kinetic energy during slip due to increased drag forces from fluid on particles. The presence of fluid during the stick phase of loading promotes a more stable configuration evidenced by higher particle coordination number. Our coupled fluid-particle simulations provide grain-scale information that improves understanding of slip instabilities and illuminates details of phenomenological, macroscale observations.

A study on the unsteady flow of two immiscible micropolar and Newtonian fluids through a horizontal channel: A numerical approach

NASA Astrophysics Data System (ADS)

Devakar, M.; Raje, Ankush

2018-05-01

The unsteady flow of two immiscible micropolar and Newtonian fluids through a horizontal channel is considered. In addition to the classical no-slip and hyper-stick conditions at the boundary, it is assumed that the fluid velocities and shear stresses are continuous across the fluid-fluid interface. Three cases for the applied pressure gradient are considered to study the problem: one with constant pressure gradient and the other two cases with time-dependent pressure gradients, viz. periodic and decaying pressure gradient. The Crank-Nicolson approach has been used to obtain numerical solutions for fluid velocity and microrotation for diverse sets of fluid parameters. The nature of fluid velocities and microrotation with various values of pressure gradient, Reynolds number, ratio of viscosities, micropolarity parameter and time is illustrated through graphs. It has been observed that micropolarity parameter and ratio of viscosities reduce the fluid velocities.

Fluid therapy for children: facts, fashions and questions

PubMed Central

Holliday, Malcolm A; Ray, Patricio E; Friedman, Aaron L

2007-01-01

Fluid therapy restores circulation by expanding extracellular fluid. However, a dispute has arisen regarding the nature of intravenous therapy for acutely ill children following the development of acute hyponatraemia from overuse of hypotonic saline. The foundation on which correct maintenance fluid therapy is built is examined and the difference between maintenance fluid therapy and restoration or replenishment fluid therapy for reduction in extracellular fluid volume is delineated. Changing practices and the basic physiology of extracellular fluid are discussed. Some propose changing the definition of “maintenance therapy” and recommend isotonic saline be used as maintenance and restoration therapy in undefined amounts leading to excess intravenous sodium chloride intake. Intravenous fluid therapy for children with volume depletion should first restore extracellular volume with measured infusions of isotonic saline followed by defined, appropriate maintenance therapy to replace physiological losses according to principles established 50 years ago. PMID:17175577

Apparatus and Methods for Fluid Storage and Delivery

NASA Technical Reports Server (NTRS)

Parazynski, Scott E. (Inventor); Bue, Grant C. (Inventor); Urban, Kase C. (Inventor); Schaefbauer, Mark E. (Inventor)

2014-01-01

An apparatus and method for storing and delivering fluid to a person comprises, in at least one specific embodiment, a fluid reservoir having an internal volume therein with an opening disposed through a first wall or a second wall of the fluid reservoir and located toward a first end of the fluid reservoir. A first portion of a tube can be exterior to the fluid reservoir and a second portion of the tube can be disposed through the opening and within the internal volume. At least one insulation layer can be disposed about the exterior of the first wall of the fluid reservoir. The second wall of the fluid reservoir can be configured for transferring heat from or to the internal volume or from the person. At least one baffle is disposed within the internal volume and connected to the first wall and the second wall of the fluid reservoir.

Fluid sampling tool

DOEpatents

Johnston, Roger G.; Garcia, Anthony R. E.; Martinez, Ronald K.

2001-09-25

The invention includes a rotatable tool for collecting fluid through the wall of a container. The tool includes a fluid collection section with a cylindrical shank having an end portion for drilling a hole in the container wall when the tool is rotated, and a threaded portion for tapping the hole in the container wall. A passageway in the shank in communication with at least one radial inlet hole in the drilling end and an opening at the end of the shank is adapted to receive fluid from the container. The tool also includes a cylindrical chamber affixed to the end of the shank opposite to the drilling portion thereof for receiving and storing fluid passing through the passageway. The tool also includes a flexible, deformable gasket that provides a fluid-tight chamber to confine kerf generated during the drilling and tapping of the hole. The invention also includes a fluid extractor section for extracting fluid samples from the fluid collecting section.

Device and method for measuring multi-phase fluid flow and density of fluid in a conduit having a gradual bend

DOEpatents

Ortiz, M.G.; Boucher, T.J.

1998-10-27

A system is described for measuring fluid flow in a conduit having a gradual bend or arc, and a straight section. The system includes pressure transducers, one or more disposed in the conduit on the outside of the arc, and one disposed in the conduit in a straight section thereof. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow. 1 fig.

Labyrinth and cerebral-spinal fluid pressure changes in guinea pigs and monkeys during simulated zero G

NASA Technical Reports Server (NTRS)

Parker, D. E.

1977-01-01

This study was undertaken to explore the hypothesis that shifts of body fluids from the legs and torso toward the head contribute to the motion sickness experienced by astronauts and cosmonauts. The shifts in body fluids observed during zero-G exposure were simulated by elevating guinea pigs' and monkeys' torsos and hindquarters. Cerebral-spinal fluid pressure was recorded from a transducer located in a brain ventricle; labyrinth fluid pressure was recorded from a pipette cemented in a hole in a semicircular canal. An anticipated divergence in cerebral-spinal fluid pressure and labyrinth fluid pressure during torso elevation was not observed. The results of this study do not support a fluid shift mechanism of zero-G-induced motion sickness. However, a more complete test of the fluid shift mechanism would be obtained if endolymph and perilymph pressure changes were determined separately; we have been unable to perform this test to date.

Generating perfect fluid spheres in general relativity

NASA Astrophysics Data System (ADS)

Boonserm, Petarpa; Visser, Matt; Weinfurtner, Silke

2005-06-01

Ever since Karl Schwarzschild’s 1916 discovery of the spacetime geometry describing the interior of a particular idealized general relativistic star—a static spherically symmetric blob of fluid with position-independent density—the general relativity community has continued to devote considerable time and energy to understanding the general-relativistic static perfect fluid sphere. Over the last 90 years a tangle of specific perfect fluid spheres has been discovered, with most of these specific examples seemingly independent from each other. To bring some order to this collection, in this article we develop several new transformation theorems that map perfect fluid spheres into perfect fluid spheres. These transformation theorems sometimes lead to unexpected connections between previously known perfect fluid spheres, sometimes lead to new previously unknown perfect fluid spheres, and in general can be used to develop a systematic way of classifying the set of all perfect fluid spheres.

Organosiloxane working fluids for the liquid droplet radiator

NASA Technical Reports Server (NTRS)

Buch, R. R.; Huntress, A. R.

1985-01-01

Siloxane-based working fluids for advanced space radiators requiring direct fluid exposure to the space environment are evaluated. Isolation of five candidate fluids by vacuum distillation from existing siloxane polymers is discussed. The five fluids recovered include a polydimethylsiloxane, three phenyl-containing siloxanes, and a methylhexylsiloxane. Vapor pressures and viscosities for the five fluids are reported over the temperature range of 250 to 400 K. Use of thermal-gravimetric analysis to reliably estimate vapor pressures of 10 to the -8 power Pascals is described. Polydimethylsiloxane (PDMS) and polymethylphenylsiloxane (PMPS) are selected from the five candidate fluids based on favorable vapor pressure and viscosity, as well as perceived stability in low-Earth orbit environments. Characterization of these fluids by infrared spectroscopy, Si-29 NMR, gel-permeation chromatography, and liquid chromatography is presented. Both fluids consist of narrow molecular weight distributions, with average molecular weights of about 2500 for PDMS and 1300 for PMPS.

Visualization of various working fluids flow regimes in gravity heat pipe

NASA Astrophysics Data System (ADS)

Nemec, Patrik

Heat pipe is device working with phase changes of working fluid inside hermetically closed pipe at specific pressure. The phase changes of working fluid from fluid to vapour and vice versa help heat pipe to transport high heat flux. Amount of heat flux transferred by heat pipe, of course depends on kind of working fluid. The article deal about visualization of various working fluids flow regimes in glass gravity heat pipe by high speed camera and processes casing inside during heat pipe operation. Experiment working fluid flow visualization is performed with two glass heat pipes with different inner diameter (13 mm and 22 mm) filled with water, ethanol and fluorinert FC 72. The working fluid flow visualization explains the phenomena as a working fluid boiling, nucleation of bubbles, and vapour condensation on the wall, vapour and condensate flow interaction, flow down condensate film thickness on the wall occurred during the heat pipe operation.

Engineering fluid flow using sequenced microstructures

NASA Astrophysics Data System (ADS)

Amini, Hamed; Sollier, Elodie; Masaeli, Mahdokht; Xie, Yu; Ganapathysubramanian, Baskar; Stone, Howard A.; di Carlo, Dino

2013-05-01

Controlling the shape of fluid streams is important across scales: from industrial processing to control of biomolecular interactions. Previous approaches to control fluid streams have focused mainly on creating chaotic flows to enhance mixing. Here we develop an approach to apply order using sequences of fluid transformations rather than enhancing chaos. We investigate the inertial flow deformations around a library of single cylindrical pillars within a microfluidic channel and assemble these net fluid transformations to engineer fluid streams. As these transformations provide a deterministic mapping of fluid elements from upstream to downstream of a pillar, we can sequentially arrange pillars to apply the associated nested maps and, therefore, create complex fluid structures without additional numerical simulation. To show the range of capabilities, we present sequences that sculpt the cross-sectional shape of a stream into complex geometries, move and split a fluid stream, perform solution exchange and achieve particle separation. A general strategy to engineer fluid streams into a broad class of defined configurations in which the complexity of the nonlinear equations of fluid motion are abstracted from the user is a first step to programming streams of any desired shape, which would be useful for biological, chemical and materials automation.

Quantitation of sperm bindable IgA and IgG in seminal fluid.

PubMed

Howe, S E; Lynch, D M

1986-05-01

Seminal fluid and serum from 95 infertile males were assayed for sperm bindable immunoglobulins using an indirect ELISA with whole target sperm. The ELISA method was compared to seminal fluid and serum immobilization and agglutination assays (functional assays). In this infertile group, the ELISA assay was positive in 22% of seminal fluids (greater than 1.2 fg IgA/sperm and greater than 0.3 fg IgG/sperm). The seminal fluid antibodies were IgA and had an accompanying elevated IgG component in 78% of patients. There was a 96% correlation between negative seminal fluid functional assays and negative ELISA, and a 95% correlation between positive seminal fluid functional assays and positive ELISA. Positive serum sperm antibody tests were found in 71% of the infertile males with positive seminal fluid sperm antibodies, but 29% of the infertile males with strongly positive IgA seminal fluid sperm antibodies showed normal levels of serum sperm antibodies by either ELISA or functional assays. The ELISA method gives reproducible quantitation of sperm antibodies in seminal fluid and correlates well with accepted functional assays. Comparisons with serum sperm antibody assays suggests that seminal fluid sperm antibody analysis complements the serum analysis of sperm antibodies.

Fluid flow in deforming media: interpreting stable isotope signatures of marbles

NASA Astrophysics Data System (ADS)

Bond, C. E.

2016-12-01

Fluid flow in the crust is controlled by permeable networks. These networks can be created and destroyed dynamically during rock deformation. Rock deformation is therefore critical in controlling fluid pathways in the crust and hence the location of mineral and other resources. Here, evidence for deformation-enhanced fluid infiltration shows that a range of deformation mechanisms control fluid flow and chemical and isotopic equilibration. The results attest to localised fluid infiltration within a single metamorphic terrain (12km) over a range of metamorphic grades; ecologite- blueschist to greenschist. For fluid infiltrating marbles during ductile deformation, chemical and isotopic signatures are now homogenous; whilst fluid infiltration associated with brittle deformation results in chemical and isotopic heterogeneity at a microscale. The findings demonstrate how ductile deformation enhances equilibration of δ18O at a grain scale whilst brittle deformation does not. The control of deformation mechanisms in equilibrating isotopic and chemical heterogeneities have implications for the understanding of fluid-rock interaction in the crust. Interpretation of bulk stable isotope data, particularly in the use of isotope profiles to determine fluid fluxes into relatively impermeable units that have been deformed need to be used with care when trying to determine fluid fluxes and infiltration mechanisms.

Effect of fluid-colloid interactions on the mobility of a thermophoretic microswimmer in non-ideal fluids.

PubMed

Fedosov, Dmitry A; Sengupta, Ankush; Gompper, Gerhard

2015-09-07

Janus colloids propelled by light, e.g., thermophoretic particles, offer promising prospects as artificial microswimmers. However, their swimming behavior and its dependence on fluid properties and fluid-colloid interactions remain poorly understood. Here, we investigate the behavior of a thermophoretic Janus colloid in its own temperature gradient using numerical simulations. The dissipative particle dynamics method with energy conservation is used to investigate the behavior in non-ideal and ideal-gas like fluids for different fluid-colloid interactions, boundary conditions, and temperature-controlling strategies. The fluid-colloid interactions appear to have a strong effect on the colloid behavior, since they directly affect heat exchange between the colloid surface and the fluid. The simulation results show that a reduction of the heat exchange at the fluid-colloid interface leads to an enhancement of colloid's thermophoretic mobility. The colloid behavior is found to be different in non-ideal and ideal fluids, suggesting that fluid compressibility plays a significant role. The flow field around the colloid surface is found to be dominated by a source-dipole, in agreement with the recent theoretical and simulation predictions. Finally, different temperature-control strategies do not appear to have a strong effect on the colloid's swimming velocity.

Effects of real fluid properties on axial turbine meanline design and off-design analysis

NASA Astrophysics Data System (ADS)

MacLean, Cameron

The effects of real fluid properties on axial turbine meanline analysis have been investigated employing two meanline analysis codes, namely Turbine Meanline Design (TMLD) and Turbine Meanline Off-Design (TMLO). The previously developed TMLD code assumed the working fluid was an ideal gas. Therefore it was modified to use real fluid properties. TMLO was then developed from TMLD Both codes can be run using either the ideal gas assumption or real fluid properties. TMLD was employed for the meanline design of several axial turbines for a range of inlet conditions, using both the ideal gas assumption and real fluid properties. The resulting designs were compared to see the effects of real fluid properties. Meanline designs, generated using the ideal gas assumption, were then analysed with TMLO using real fluid properties. This was done over a range of inlet conditions that correspond to varying degrees of departure from ideal gas conditions. The goal was to show how machines designed with the ideal gas assumption would perform with the real working fluid. The working fluid used in both investigations was supercritical carbon dioxide. Results from the investigation show that real fluid properties had a strong effect on the gas path areas of the turbine designs as well as the performance of turbines designed using the ideal gas assumption. Specifically, power output and the velocities of the working fluid were affected. It was found that accounting for losses tended to lessen the effects of the real fluid properties.

Fluid Sources at the Panasqueira Tungsten-Vein Deposit

NASA Astrophysics Data System (ADS)

Lecumberri-Sanchez, P.; Heinrich, C. A.; Wälle, M.; Codeço, M.; Weis, P.; Pinto, F.; Vieira, R.

2017-12-01

Panasqueira is a world-class tungsten-vein deposit. Several paragenetic stages have been proposed (Polya et al., 2000) including two pre-ore stages (crack-seal quartz-seam, and muscovite selvages) and four ore stages (main oxide-silicate stage, main sulfide stage, pyrrhotite alteration stage, and late carbonate stage). In this study, compositions of the mineralizing fluids at Panasqueira have been determined by a combination of detailed petrography, microthermometric measurements and LA-ICPMS analyses. We have characterized the fluids related to several mineralizing stages and determined the information they provide about the fluid sources in this system. Three fluid generations recorded in pseudosecondary to secondary fluid inclusions have been identified at Panasqueira. The first fluid generation identified consists of CO2-bearing fluid inclusions with homogenization temperatures ranging between 260 and 320 °C and salinities between 5 and 8 eq wt % NaCl. Petrographic constraints indicate that this first generation (1) is paragenetically related to the main oxide-silicate stage. Two lower-temperature CO2-absent fluid generations (2a and 2b) have been identified and are represented by secondary fluid inclusions postdating the main oxide-silicate stage. This stage was likely trapped under high pressures and lithostatic conditions (Jacques and Pascal, 2017). Generation (2a) consists of high-salinity (20-30 eq wt % NaCl) fluids with homogenization temperatures ranging between 180°C and 250°C. Generation (2b) consists of low-salinity (<2 wt %) low homogenization temperature (100-150°C) fluid inclusions. Conclusive petrographic evidence of the relationship between these two late-stage fluid generations and specific late mineral stages are scarce. However, fluid compositions suggests that generation (2a) is related to the main sulfide stage and generation (2b) is related to the late carbonate stage. The PTX evolution of fluids at Panasqueira indicate a transition from magmatic dominated fluids to a likely influx of non-magmatic fluids at least in the latest stages of mineralization (main sulfide stage and late carbonate stage) which is in good agreement with recent results from isotopic studies (Codeço et al., 2017).

Characterization of gas chemistry and noble-gas isotope ratios of inclusion fluids in magmatic-hydrothermal and magmatic-steam alunite

USGS Publications Warehouse

Landis, G.P.; Rye, R.O.

2005-01-01

Chemical and isotope data were obtained for the active gas and noble gas of inclusion fluids in coarse-grained samples of magmatic-hydrothermal and magmatic-steam alunite from well-studied deposits (Marysvale, Utah; Tambo, Chile; Tapajo??s, Brazil; Cactus, California; Pierina, Peru), most of which are discussed in this Volume. Primary fluid inclusions in the alunite typically are less than 0.2 ??m but range up to several micrometers. Analyses of the active-gas composition of these alunite-hosted inclusion fluids released in vacuo by both crushing and heating indicate consistent differences in the compositions of magmatic-hydrothermal and magmatic-steam fluids. The compositions of fluids released by crushing were influenced by contributions from significant populations of secondary inclusions that trapped largely postdepositional hydrothermal fluids. Thermally released fluids gave the best representation of the fluids that formed primary alunite. The data are consistent with current models for the evolution of magmatic-hydrothermal and magmatic-steam fluids. Magmatic-steam fluids are vapor-dominant, average about 49 mol% H2O, and contain N2, H2, CH4, CO, Ar, He, HF, and HCl, with SO2 the dominant sulfur gas (average SO2/ H2S=202). In contrast, magmatic-hydrothermal fluids are liquid-dominant, average about 88 mol% H2O, and N2, H2, CO2, and HF, with H2S about as abundant as SO2 (average SO2/H2 S=0.7). The low SO2/H2S and N2/Ar ratios, and the near-absence of He in magmatic-hydrothermal fluids, are consistent with their derivation from degassed condensed magmatic fluids whose evolution from reduced-to-oxidized aqueous sulfur species was governed first by rock and then by fluid buffers. The high SO2/H2S and N2/Ar with significant concentrations of He in magmatic-steam fluids are consistent with derivation directly from a magma. None of the data supports the entrainment of atmospheric gases or mixing of air-saturated gases in meteoric water in either magmatic-hydrothermal or magmatic-steam fluids. Thus, the oxidation of SO2 to aqueous sulfate in the magmatic-steam fluids did not result from mixing with atmospheric oxygen. Both of the fluid types are characterized by high H2 contents that range from 0.2 mol% to the extraordinarily large amounts (66 mol%) observed in some magmatic-steam fluids. Modeling of gas speciation using SOLVGAS requires most of the gas species to have been in disequilibrium at the time of their trapping in the fluid inclusions. The origin of such extreme H2 concentrations, although problematic, is thought to be largely related to accumulation of H2 from the reaction of water with ferrous iron during the rise of magma and probably even after exsolution of fluid from a magma. The large contents of reduced gases in the inclusion fluids are far in excess of those observed in volcanic emanations, and are thought to reflect the close "sampling position" of the host alunite relative to the location of the magma. Isotope ratios of He and Ne indicate largely crustal sources for these gases in the alunite parental fluids derived from Tertiary magmas, but a greater mantle component for the gases in alunite parental fluids derived from Proterozoic magmas.

Proteomic analysis of mare follicular fluid during late follicle development

PubMed Central

2011-01-01

Background Follicular fluid accumulates into the antrum of follicle from the early stage of follicle development. Studies on its components may contribute to a better understanding of the mechanisms underlying follicular development and oocyte quality. With this objective, we performed a proteomic analysis of mare follicular fluid. First, we hypothesized that proteins in follicular fluid may differ from those in the serum, and also may change during follicle development. Second, we used four different approaches of Immunodepletion and one enrichment method, in order to overcome the masking effect of high-abundance proteins present in the follicular fluid, and to identify those present in lower abundance. Finally, we compared our results with previous studies performed in mono-ovulant (human) and poly-ovulant (porcine and canine) species in an attempt to identify common and/or species-specific proteins. Methods Follicular fluid samples were collected from ovaries at three different stages of follicle development (early dominant, late dominant and preovulatory). Blood samples were also collected at each time. The proteomic analysis was carried out on crude, depleted and enriched follicular fluid by 2D-PAGE, 1D-PAGE and mass spectrometry. Results Total of 459 protein spots were visualized by 2D-PAGE of crude mare follicular fluid, with no difference among the three physiological stages. Thirty proteins were observed as differentially expressed between serum and follicular fluid. Enrichment method was found to be the most powerful method for detection and identification of low-abundance proteins from follicular fluid. Actually, we were able to identify 18 proteins in the crude follicular fluid, and as many as 113 in the enriched follicular fluid. Inhibins and a few other proteins involved in reproduction could only be identified after enrichment of follicular fluid, demonstrating the power of the method used. The comparison of proteins found in mare follicular fluid with proteins previously identified in human, porcine and canine follicular fluids, led to the identification of 12 common proteins and of several species-specific proteins. Conclusions This study provides the first description of mare follicular fluid proteome during the late follicle development stages. We identified several proteins from crude, depleted and enriched follicular fluid. Our results demonstrate that the enrichment method, combined with 2D-PAGE and mass spectrometry, can be successfully used to visualize and further identify the low-abundance proteins in the follicular fluid. PMID:21923925

Carbon Dioxide: The Other Planetary Fluid

NASA Astrophysics Data System (ADS)

Glaser, S.; Gamez, D.; Shock, E.

2016-12-01

Cometary and interstellar ices have carbon dioxide to water mole ratios of up to 0.3. When melted, such high levels of carbon dioxide cannot all be dissolved in the aqueous phase and instead partition into a CO2-rich (carbonic) fluid. This implies that during the accretion and formation of planetary systems carbonic fluids are not only possible, but common. In fact, they make up the atmosphere of Venus, are found bubbling out of Champagne Vent in the Pacific Ocean, and are documented by metamorphic fluid inclusions. Examination of phase diagrams reveals the conditions where carbonic fluids will exist or predominate. Carbonic fluids are predicted to exist in Earth's subduction zones and under the ice of small ocean worlds. CO2 had previously been shown to completely dissolve into NH­­3­-H­­2O oceans on small icy bodies by forming ammonium carbonate, but the newer measurements of CO2­ abundances indicate that not all of the CO2 can partition into the aqueous fluid as ammonium carbonate. The remaining CO2 would necessarily form a separate carbonic fluid making it likely that liquid CO2 would be a major oceanic component on some small icy bodies. The enhanced solubility of nonpolar and slightly polar organic compounds in carbonic fluids relative to aqueous fluids means that generation, transport, and deposition processes can be greatly enhanced in those cases where carbonic fluids occur. As an example, the solubility of benzoic acid, a polar compound, is about an order of magnitude greater in carbonic than in aqueous fluids, which is surprising given that water is a polar solvent and carbon dioxide is a nonpolar solvent. Anthracene, a nonpolar compound, has an even greater solubility difference between carbonic and aqueous fluids at approximately four orders of magnitude. Highly polar compounds, including most of the building blocks of life, are more soluble in aqueous fluids than in carbonic fluids. The solubility difference of organic molecules in carbonic fluids relative to aqueous fluids determines the distribution of the building blocks of life in planetary systems. Partitioning of organics into a carbonic fluid may be the mechanism of removing biochemically irrelevant molecules from the aqueous phase and enabling the emergence of life.

Proteomic analysis of mare follicular fluid during late follicle development.

PubMed

Fahiminiya, Somayyeh; Labas, Valérie; Roche, Stéphane; Dacheux, Jean-Louis; Gérard, Nadine

2011-09-17

Follicular fluid accumulates into the antrum of follicle from the early stage of follicle development. Studies on its components may contribute to a better understanding of the mechanisms underlying follicular development and oocyte quality. With this objective, we performed a proteomic analysis of mare follicular fluid. First, we hypothesized that proteins in follicular fluid may differ from those in the serum, and also may change during follicle development. Second, we used four different approaches of Immunodepletion and one enrichment method, in order to overcome the masking effect of high-abundance proteins present in the follicular fluid, and to identify those present in lower abundance. Finally, we compared our results with previous studies performed in mono-ovulant (human) and poly-ovulant (porcine and canine) species in an attempt to identify common and/or species-specific proteins. Follicular fluid samples were collected from ovaries at three different stages of follicle development (early dominant, late dominant and preovulatory). Blood samples were also collected at each time. The proteomic analysis was carried out on crude, depleted and enriched follicular fluid by 2D-PAGE, 1D-PAGE and mass spectrometry. Total of 459 protein spots were visualized by 2D-PAGE of crude mare follicular fluid, with no difference among the three physiological stages. Thirty proteins were observed as differentially expressed between serum and follicular fluid. Enrichment method was found to be the most powerful method for detection and identification of low-abundance proteins from follicular fluid. Actually, we were able to identify 18 proteins in the crude follicular fluid, and as many as 113 in the enriched follicular fluid. Inhibins and a few other proteins involved in reproduction could only be identified after enrichment of follicular fluid, demonstrating the power of the method used. The comparison of proteins found in mare follicular fluid with proteins previously identified in human, porcine and canine follicular fluids, led to the identification of 12 common proteins and of several species-specific proteins. This study provides the first description of mare follicular fluid proteome during the late follicle development stages. We identified several proteins from crude, depleted and enriched follicular fluid. Our results demonstrate that the enrichment method, combined with 2D-PAGE and mass spectrometry, can be successfully used to visualize and further identify the low-abundance proteins in the follicular fluid.

Multiple stable isotope fronts during non-isothermal fluid flow

NASA Astrophysics Data System (ADS)

Fekete, Szandra; Weis, Philipp; Scott, Samuel; Driesner, Thomas

2018-02-01

Stable isotope signatures of oxygen, hydrogen and other elements in minerals from hydrothermal veins and metasomatized host rocks are widely used to investigate fluid sources and paths. Previous theoretical studies mostly focused on analyzing stable isotope fronts developing during single-phase, isothermal fluid flow. In this study, numerical simulations were performed to assess how temperature changes, transport phenomena, kinetic vs. equilibrium isotope exchange, and isotopic source signals determine mineral oxygen isotopic compositions during fluid-rock interaction. The simulations focus on one-dimensional scenarios, with non-isothermal single- and two-phase fluid flow, and include the effects of quartz precipitation and dissolution. If isotope exchange between fluid and mineral is fast, a previously unrecognized, significant enrichment in heavy oxygen isotopes of fluids and minerals occurs at the thermal front. The maximum enrichment depends on the initial isotopic composition of fluid and mineral, the fluid-rock ratio and the maximum change in temperature, but is independent of the isotopic composition of the incoming fluid. This thermally induced isotope front propagates faster than the signal related to the initial isotopic composition of the incoming fluid, which forms a trailing front behind the zone of transient heavy oxygen isotope enrichment. Temperature-dependent kinetic rates of isotope exchange between fluid and rock strongly influence the degree of enrichment at the thermal front. In systems where initial isotope values of fluids and rocks are far from equilibrium and isotope fractionation is controlled by kinetics, the temperature increase accelerates the approach of the fluid to equilibrium conditions with the host rock. Consequently, the increase at the thermal front can be less dominant and can even generate fluid values below the initial isotopic composition of the input fluid. As kinetics limit the degree of isotope exchange, a third front may develop in kinetically limited systems, which propagates with the advection speed of the incoming fluid and is, therefore, traveling fastest. The results show that oxygen isotope signatures at thermal fronts recorded in rocks and veins that experienced isotope exchange with fluids can easily be misinterpreted, namely if bulk analytical techniques are applied. However, stable isotope microanalysis on precipitated minerals may - if later isotope exchange is kinetically limited - provide a valuable archive of the transient thermal and hydrological evolution of a system.

Amylase, lipase, and volume of drainage fluid in gastrectomy for the early detection of complications caused by pancreatic leakage.

PubMed

Seo, Kyung Won; Yoon, Ki Young; Lee, Sang Ho; Shin, Yeon Myung; Choi, Kyung Hyun; Hwang, Hyun Yong

2011-12-01

Pancreatic leakage is a serious complication of gastrectomy due to stomach cancer. Therefore, we analyzed amylase and lipase concentrations in blood and drainage fluid, and evaluated the volume of drainage fluid to discern their usefulness as markers for the early detection of serious pancreatic leakage requiring reoperation after gastrectomy. From January 2001 to December 2007, we retrospectively analyzed data from 24,072 patient samples. We divided patients into two groups; 1) complications with pancreatic leakage (CG), and 2) no complications associated with pancreatic leakage (NCG). Values of amylase and lipase in the blood and drainage fluid, volume of the drainage fluid, and relationships among the volumes, amylase values, and lipase values in the drainage fluid were evaluated, respectively in the two groups. The mean amylase values of CG were significantly higher than those of NCG in blood and drainage fluid (P < 0.05). For lipase, statistically significant differences were observed in drainage fluid (P < 0.05). The mean volume (standard deviation) of the drained fluid through the tube between CG (n = 22) and NCG (n = 236) on postoperative day 1 were 368.41 (266.25) and 299.26 (300.28), respectively. There were no statistically significant differences between the groups (P = 0.298). There was a correlation between the amylase and lipase values in the drainage fluid (r = 0.812, P = 0.000). Among postoperative amylase and lipase values in blood and drainage fluid, and the volume of drainage fluid, the amylase in drainage fluid was better differentiated between CG and NCG than other markers. The volume of the drainage fluid did not differ significantly between groups.

Molecular mechanics and structure of the fluid-solid interface in simple fluids

NASA Astrophysics Data System (ADS)

Wang, Gerald J.; Hadjiconstantinou, Nicolas G.

2017-09-01

Near a fluid-solid interface, the fluid spatial density profile is highly nonuniform at the molecular scale. This nonuniformity can have profound effects on the dynamical behavior of the fluid and has been shown to play an especially important role when modeling a wide variety of nanoscale heat and momentum transfer phenomena. We use molecular-mechanics arguments and molecular-dynamics (MD) simulations to develop a better understanding of the structure of the first fluid layer directly adjacent to the solid in the layering regime, as delineated by a nondimensional number that compares the effects of wall-fluid interaction to thermal energy. Using asymptotic analysis of the Nernst-Planck equation, we show that features of the fluid density profile close to the wall, such as the areal density of the first layer ΣFL (defined as the number of atoms in this layer per unit of fluid-solid interfacial area), can be expressed as polynomial functions of the fluid average density ρave. This is found to be in agreement with MD simulations, which also show that the width of the first layer hFL is a linear function of the average density and only a weak function of the temperature T . These results can be combined to show that, for system average densities corresponding to a dense fluid (ρave≥0.7 ), the ratio C ≡ΣFLρavehFL, representing a density enhancement with respect to the bulk fluid, depends only weakly on temperature and is essentially independent of density. Further MD simulations suggest that the above results, nominally valid for large systems (solid in contact with semi-infinite fluid), also describe fluid-solid interfaces under considerable nanoconfinement, provided ρave is appropriately defined.

Non-Newtonian fluid flow in 2D fracture networks

NASA Astrophysics Data System (ADS)

Zou, L.; Håkansson, U.; Cvetkovic, V.

2017-12-01

Modeling of non-Newtonian fluid (e.g., drilling fluids and cement grouts) flow in fractured rocks is of interest in many geophysical and industrial practices, such as drilling operations, enhanced oil recovery and rock grouting. In fractured rock masses, the flow paths are dominated by fractures, which are often represented as discrete fracture networks (DFN). In the literature, many studies have been devoted to Newtonian fluid (e.g., groundwater) flow in fractured rock using the DFN concept, but few works are dedicated to non-Newtonian fluids.In this study, a generalized flow equation for common non-Newtonian fluids (such as Bingham, power-law and Herschel-Bulkley) in a single fracture is obtained from the analytical solutions for non-Newtonian fluid discharge between smooth parallel plates. Using Monte Carlo sampling based on site characterization data for the distribution of geometrical features (e.g., density, length, aperture and orientations) in crystalline fractured rock, a two dimensional (2D) DFN model is constructed for generic flow simulations. Due to complex properties of non-Newtonian fluids, the relationship between fluid discharge and the pressure gradient is nonlinear. A Galerkin finite element method solver is developed to iteratively solve the obtained nonlinear governing equations for the 2D DFN model. Using DFN realizations, simulation results for different geometrical distributions of the fracture network and different non-Newtonian fluid properties are presented to illustrate the spatial discharge distributions. The impact of geometrical structures and the fluid properties on the non-Newtonian fluid flow in 2D DFN is examined statistically. The results generally show that modeling non-Newtonian fluid flow in fractured rock as a DFN is feasible, and that the discharge distribution may be significantly affected by the geometrical structures as well as by the fluid constitutive properties.

Goal-directed Fluid Therapy Does Not Reduce Primary Postoperative Ileus after Elective Laparoscopic Colorectal Surgery: A Randomized Controlled Trial.

PubMed

Gómez-Izquierdo, Juan C; Trainito, Alessandro; Mirzakandov, David; Stein, Barry L; Liberman, Sender; Charlebois, Patrick; Pecorelli, Nicolò; Feldman, Liane S; Carli, Franco; Baldini, Gabriele

2017-07-01

Inadequate perioperative fluid therapy impairs gastrointestinal function. Studies primarily evaluating the impact of goal-directed fluid therapy on primary postoperative ileus are missing. The objective of this study was to determine whether goal-directed fluid therapy reduces the incidence of primary postoperative ileus after laparoscopic colorectal surgery within an Enhanced Recovery After Surgery program. Randomized patient and assessor-blind controlled trial conducted in adult patients undergoing laparoscopic colorectal surgery within an Enhanced Recovery After Surgery program. Patients were assigned randomly to receive intraoperative goal-directed fluid therapy (goal-directed fluid therapy group) or fluid therapy based on traditional principles (control group). Primary postoperative ileus was the primary outcome. One hundred twenty-eight patients were included and analyzed (goal-directed fluid therapy group: n = 64; control group: n = 64). The incidence of primary postoperative ileus was 22% in the goal-directed fluid therapy and 22% in the control group (relative risk, 1; 95% CI, 0.5 to 1.9; P = 1.00). Intraoperatively, patients in the goal-directed fluid therapy group received less intravenous fluids (mainly less crystalloids) but a greater volume of colloids. The increase of stroke volume and cardiac output was more pronounced and sustained in the goal-directed fluid therapy group. Length of hospital stay, 30-day postoperative morbidity, and mortality were not different. Intraoperative goal-directed fluid therapy compared with fluid therapy based on traditional principles does not reduce primary postoperative ileus in patients undergoing laparoscopic colorectal surgery in the context of an Enhanced Recovery After Surgery program. Its previously demonstrated benefits might have been offset by advancements in perioperative care.

[Perioperative fluid therapy in perforated ulcers].

PubMed

Bjerre, Catherine Collin; Holte, Kathrine

2009-04-27

Surgery for perforated ulcers is one of the most common emergency surgical procedures. Approximately 400 procedures are performed each year in Denmark and mortality is high, reaching close to 30% at 30 days postoperatively. The importance of perioperative fluid administration during the perioperative course remains unclear. The purpose of this study is to describe the perioperative fluid management in these patients in order to identify problem areas (if any) and to create a basis on which future trials on fluid management in this patient group may be designed. Retrospective survey of 45 consecutive patients operated for perforated ulcers over a 3-year period between 1 January 2003 and 31 December 2005 in the surgical department of a university hospital. Data that would permit rational fluid therapy are not being collected on a regular basis. Fluid balance charts were kept for 42 patients on the day of operation (89%), for 29 patients on the first post-operative day (61%), for 17 patients on the second post-operative day (36%) and for 12 patients (25%) on the third post-operative day. No patients were weighed for assessment of fluid status. Perioperative fluid administration varied extensively, with fluid balance on the day of surgery ranging from -45 to 8,030 ml (median 2688 ml) and a cumulated fluid balance of 7,2 litres (1,875-14,565 ml) three days postoperatively. Generally, patients had no fluid administered prior to surgery (median 0 ml, applying to 41 patients (87%) range 0-4,500 ml). Both the preoperative fluid management and the postoperative monitoring of the fluid balance are suboptimal and should be optimized. Individualized (goal-directed) fluid administration aiming at optimizing the oxygen supply to the peripheral tissues is warranted and is recommended to high-risk emergency surgery patients.

Molecular Mechanism of Pancreatic and Salivary Glands Fluid and HCO3− Secretion

PubMed Central

Lee, Min Goo; Ohana, Ehud; Park, Hyun Woo; Yang, Dongki; Muallem, Shmuel

2013-01-01

Fluid and HCO3− secretion is a vital function of all epithelia and is required for the survival of the tissue. Aberrant fluid and HCO3− secretion is associated with many epithelial diseases, such as cystic fibrosis, pancreatitis, Sjögren’s syndrome and other epithelial inflammatory and autoimmune diseases. Significant progress has been made over the last 20 years in our understanding of epithelial fluid and HCO3− secretion, in particular by secretory glands. Fluid and HCO3− secretion by secretory glands is a two step process. Acinar cells secrete isotonic fluid in which the major salt is NaCl. Subsequently, the duct modifies the volume and electrolyte composition of the fluid to absorb the Cl− and secrete HCO3−. The relative volume secreted by acinar and duct cells and modification of electrolyte composition of the secreted fluids varies among secretory glands to meet their physiological functions. In the pancreas, acinar cells secrete small amount of NaCl-rich fluid, while the duct absorbs the Cl− and secretes HCO3− and the bulk of the fluid in the pancreatic juice. Fluid secretion appears to be driven by active HCO3− secretion. In the salivary glands, acinar cells secrete the bulk of the fluid in the saliva that contains high concentrations of Na+ and Cl− and fluid secretion is mediated by active Cl− secretion. The salivary glands duct absorbs both the Na+ and Cl− and secretes K+ and HCO3−. In this review, we focus on the molecular mechanism of fluid and HCO3− secretion by the pancreas and salivary glands, to highlight the similarities of the fundamental mechanisms of acinar and duct cell functions, and point the differences to meet glands specific secretions. PMID:22298651

Association Between Maintenance Fluid Tonicity and Hospital-Acquired Hyponatremia

PubMed Central

Carandang, Francis; Anglemyer, Andrew; Longhurst, Christopher A.; Krishnan, Gomathi; Alexander, Steven R.; Kahana, Madelyn; Sutherland, Scott M.

2013-01-01

Objective To evaluate whether the administration of hypotonic fluids, when compared with isotonic fluids, is associated with a greater risk for hyponatremia in hospitalized children. Study design Informatics-enabled cohort study of all hospitalizations at Lucile Packard Children’s Hospital between April 2009 and March 2011. Extraction and analysis of electronic medical record data identified normonatremic hospitalized children who received either hypotonic or isotonic intravenous maintenance fluids upon admission. The primary exposure was the administration of hypotonic maintenance fluids and the primary outcome was the development of hyponatremia (serum sodium < 135 mEq/L). Results 1048 normonatremic children received either hypotonic (n=674) or isotonic (n=374) maintenance fluids upon admission. Hyponatremia developed in 260 (38.6%) children receiving hypotonic fluids and 104 (27.8%) of those receiving isotonic fluids (unadjusted OR 1.63; 95th CI 1.24–2.15, p<0.001). After controlling for intergroup differences and potential confounders, patients receiving hypotonic fluids remained more likely to develop hyponatremia (adjusted OR 1.37, 95% CI 1.03–1.84). Multivariable analysis identified additional factors associated with the development of hyponatremia including surgical admission (adjusted OR 1.44, 95% CI 1.09–1.91), cardiac admitting diagnosis (adjusted OR 2.08, 95% CI 1.34–3.20) and hematology/oncology admitting diagnosis (adjusted OR 2.37, 95% CI 1.74–3.25). Conclusions Hyponatremia was common regardless of maintenance fluid tonicity, however, the administration of hypotonic maintenance fluids, when compared with isotonic fluids, was associated with a greater risk of developing hospital-acquired hyponatremia. Additional clinical characteristics modified the hyponatremic effect of hypotonic fluid, and it is possible that optimal maintenance fluid therapy now requires a more individualized approach. PMID:23998517

Fluid transport container

DOEpatents

DeRoos, Bradley G.; Downing, Jr., John P.; Neal, Michael P.

1995-01-01

An improved fluid container for the transport, collection, and dispensing of a sample fluid that maintains the fluid integrity relative to the conditions of the location at which it is taken. More specifically, the invention is a fluid sample transport container that utilizes a fitment for both penetrating and sealing a storage container under controlled conditions. Additionally, the invention allows for the periodic withdrawal of portions of the sample fluid without contamination or intermixing from the environment surrounding the sample container.

A portable self-sensing rheometer for investigation and therapy of swallowing disorders.

PubMed

O'Leary, Mark T; Hanson, Ben

2010-01-01

Dysphagia is a medical condition in which the safety or efficiency of eating and drinking is compromised. Thin, watery fluids flow too quickly through the oral anatomy during an abnormal swallow, pre-empting airway protective mechanisms, and potentially resulting in fluid entry into the lung. Dysphagia therapy consists of reducing flow speed during swallowing by increasing fluid viscosity using thickeners. Bolus viscosity must be specified and presented to the patient within a well-defined range for effective therapy. Thickeners produce non-Newtonian fluids, rendering current subjective methods for fluid assessment unreliable. Widespread quantification of fluid viscosity is presently impractical as rheometers are costly and complicated to use. Alternative techniques also have disadvantages such as operation at shear rates inappropriate to fluid use. A simple and inexpensive rheometer has been constructed to remedy this situation using a self-sensing electromagnetic actuator. This avoids the need for separate force and displacement sensors, with benefits for simplicity and robustness. The actuator and fluid interface were designed for viscosities consistent with those used for dysphagia therapy. The self-sensing rheometer was found to be able to resolve the different dynamic viscosities obtained from three commonly used therapeutic fluid consistency levels in close agreement with results from a reference laboratory rheometer. Widespread use of the rheometer could remove the subjectivity of fluid assessment, increasing accuracy of fluid specification and therapy across all consistencies and fluid types.

Method of decontaminating a contaminated fluid by using photocatalytic particles

NASA Technical Reports Server (NTRS)

Cooper, Gerald (Inventor); Ratcliff, Matthew A. (Inventor)

1994-01-01

A system for decontaminating the contaminated fluid by using photocatalytic particles. The system includes a reactor tank for holding the contaminated fluid and the photocatalytic particles suspended in the contaminated fluid to form a slurry. Light irradiates the surface of the slurry, thereby activating the photocatalytic properties of the particles. The system also includes stirring blades for continuously agitating the irradiated fluid surface and for maintaining the particles in a suspended state within the fluid. The system also includes a cross flow filter for segregating the fluid (after decomposition) from the semiconductor powder. The cross flow filter is occasionally back flushed to remove any semiconductor powder that might have caked on the filter. The semiconductor powder may be recirculated back to the tank for reuse, or may be stored for future use. A series of such systems may be used to gradually decompose a chemical in the fluid. Preferably, the fluid is pretreated to remove certain metal ions which interfere with the photocatalytic process. Such pretreatment may be accomplished by dispersing semiconductor particles within the fluid, which adsorb ions or photodeposit the metal as the free metal or its insoluble oxide or hydroxide, and then removing the semiconductor particles together with the adsorbed metal ions/oxides/hydroxide/free metal from the fluid. A method of decontaminating a contaminated fluid is also disclosed.

Collection and analysis of peritoneal fluid from healthy llamas and alpacas.

PubMed

Cebra, Christopher K; Tornquist, Susan J; Reed, Shannon K

2008-05-01

To describe a technique for abdominocentesis in camelids and report peritoneal fluid biochemical and cytologic findings from healthy llamas and alpacas. Prospective study. Animals-17 adult llamas and 5 adult alpacas. Right paracostal abdominocentesis was performed. Peritoneal fluid was collected by gravity flow into tubes containing potassium-EDTA for cell count and cytologic evaluation and lithium heparin for biochemical analysis. Blood samples were collected via jugular venipuncture into heparinized tubes at the same time. Cytologic components were quantified. Fluid pH and concentrations of total carbon dioxide, sodium, potassium, chloride, lactate, and glucose were compared between peritoneal fluid and venous blood. All but 3 camelids had peritoneal fluid cell counts of < 3,000 nucleated cells/microL, with < 2,000 neutrophils/microL and < 1,040 large mononuclear cells/microL. All but 1 had peritoneal fluid protein concentrations of > or = 2.5 g/dL. Peritoneal fluid of camelids generally contained slightly less glucose, lactate, and sodium and roughly equal concentrations of potassium and chloride as venous blood. Peritoneal fluid was collected safely from healthy camelids. Compared with blood, peritoneal fluid usually had a low cell count and protein concentration, but some individuals had higher values. Electrolyte concentrations resembled those found in blood. High cell counts and protein concentrations found in peritoneal fluid of some healthy camelids may overlap with values found in diseased camelids, complicating interpretation of peritoneal fluid values.

Noninvasive oxygen partial pressure measurement of human body fluids in vivo using magnetic resonance imaging.

PubMed

Zaharchuk, Greg; Busse, Reed F; Rosenthal, Guy; Manley, Geoffery T; Glenn, Orit A; Dillon, William P

2006-08-01

The oxygen partial pressure (pO2) of human body fluids reflects the oxygenation status of surrounding tissues. All existing fluid pO2 measurements are invasive, requiring either microelectrode/optode placement or fluid removal. The purpose of this study is to develop a noninvasive magnetic resonance imaging method to measure the pO2 of human body fluids. We developed an imaging paradigm that exploits the paramagnetism of molecular oxygen to create quantitative images of fluid oxygenation. A single-shot fast spin echo pulse sequence was modified to minimize artifacts from motion, fluid flow, and partial volume. Longitudinal relaxation rate (R1 = 1/T1) was measured with a time-efficient nonequilibrium saturation recovery method and correlated with pO2 measured in phantoms. pO2 images of human and fetal cerebrospinal fluid, bladder urine, and vitreous humor are presented and quantitative oxygenation levels are compared with prior literature estimates, where available. Significant pO2 increases are shown in cerebrospinal fluid and vitreous following 100% oxygen inhalation. Potential errors due to temperature, fluid flow, and partial volume are discussed. Noninvasive measurements of human body fluid pO2 in vivo are presented, which yield reasonable values based on prior literature estimates. This rapid imaging-based measurement of fluid oxygenation may provide insight into normal physiology as well as changes due to disease or during treatment.

Osteoarthritis screening using Raman spectroscopy of dried human synovial fluid drops

NASA Astrophysics Data System (ADS)

Esmonde-White, Karen A.; Mandair, Gurjit S.; Esmonde-White, Francis W. L.; Raaii, Farhang; Roessler, Blake J.; Morris, Michael D.

2009-02-01

We describe the use of Raman spectroscopy to investigate synovial fluid drops deposited onto fused silica microscope slides. This spectral information can be used to identify chemical changes in synovial fluid associated with osteoarthritis (OA) damage to knee joints. The chemical composition of synovial fluid is predominately proteins (enzymes, cytokines, or collagen fragments), glycosaminoglycans, and a mixture of minor components such as inorganic phosphate crystals. During osteoarthritis, the chemical, viscoelastic and biological properties of synovial fluid are altered. A pilot study was conducted to determine if Raman spectra of synovial fluid correlated with radiological scoring of knee joint damage. After informed consent, synovial fluid was drawn and x-rays were collected from the knee joints of 40 patients. Raman spectra and microscope images were obtained from the dried synovial fluid drops using a Raman microprobe and indicate a coarse separation of synovial fluid components. Individual protein signatures could not be identified; Raman spectra were useful as a general marker of overall protein content and secondary structure. Band intensity ratios used to describe protein and glycosaminoglycan structure were used in synovial fluid spectra. Band intensity ratios of Raman spectra indicate that there is less ordered protein secondary structure in synovial fluid from the damage group. Combination of drop deposition with Raman spectroscopy is a powerful approach to examining synovial fluid for the purposes of assessing osteoarthritis damage.

Solar-powered turbocompressor heat pump system

DOEpatents

Landerman, A.M.; Biancardi, F.R.; Melikian, G.; Meader, M.D.; Kepler, C.E.; Anderson, T.J.; Sitler, J.W.

1982-08-12

The turbocompressor comprises a power turbine and a compressor turbine having respective rotors and on a common shaft, rotatably supported by bearings. A first working fluid is supplied by a power loop and is expanded in the turbine. A second working fluid is compressed in the turbine and is circulated in a heat pump loop. A lubricant is mixed with the second working fluid but is excluded from the first working fluid. The bearings are cooled and lubricated by a system which circulates the second working fluid and the intermixed lubricant through the bearings. Such system includes a pump, a thermostatic expansion valve for expanding the working fluid into the space between the bearings, and a return conduit system for withdrawing the expanded working fluid after it passes through the bearings and for returning the working fluid to the evaporator. A shaft seal excludes the lubricant from the power turbine. The power loop includes a float operable by liquid working fluid in the condenser for controlling a recirculation valve so as to maintain a minimum liquid level in the condenser, while causing a feed pump to pump most of the working fluid into the vapor generator. The heat pump compressor loop includes a float in the condenser for operating and expansion valve to maintain a minimum liquid working fluid level in the condenser while causing most of the working fluid to be expanded into the evaporator.

Controversies in fluid therapy: Type, dose and toxicity

PubMed Central

McDermid, Robert C; Raghunathan, Karthik; Romanovsky, Adam; Shaw, Andrew D; Bagshaw, Sean M

2014-01-01

Fluid therapy is perhaps the most common intervention received by acutely ill hospitalized patients; however, a number of critical questions on the efficacy and safety of the type and dose remain. In this review, recent insights derived from randomized trials in terms of fluid type, dose and toxicity are discussed. We contend that the prescription of fluid therapy is context-specific and that any fluid can be harmful if administered inappropriately. When contrasting ‘‘crystalloid vs colloid’’, differences in efficacy are modest but differences in safety are significant. Differences in chloride load and strong ion difference across solutions appear to be clinically important. Phases of fluid therapy in acutely ill patients are recognized, including acute resuscitation, maintaining homeostasis, and recovery phases. Quantitative toxicity (fluid overload) is associated with adverse outcomes and can be mitigated when fluid therapy based on functional hemodynamic parameters that predict volume responsiveness and minimization of non-essential fluid. Qualitative toxicity (fluid type), in particular for iatrogenic acute kidney injury and metabolic acidosis, remain a concern for synthetic colloids and isotonic saline, respectively. Physiologically balanced crystalloids may be the ‘‘default’’ fluid for acutely ill patients and the role for colloids, in particular hydroxyethyl starch, is increasingly unclear. We contend the prescription of fluid therapy is analogous to the prescription of any drug used in critically ill patients. PMID:24834399

FLUID EVOLUTION AND MINERAL REACTIONS DURING SHEAR ZONE FORMATION AT NUSFJORD, LOFOTEN, NORWAY (Invited)

NASA Astrophysics Data System (ADS)

Kullerud, K.

2009-12-01

At Nusfjord in Lofoten, Norway, three 0.3 - 3 m thick shear zones occur in a gabbro-anorthosite. During deformation, the shear zones were infiltrated by a hydrous fluid enriched in Cl. In the central parts of the shear zones, fluid-rock interaction resulted in complete break-down of the primary mafic silicates. Complete hydration of these minerals to Cl-free amphibole and biotite suggests that the hydrous fluid was present in excess during deformation in these parts of the shear zones. Along the margins of the shear zones, however, the igneous mafic silicates (Cpx, Bt, Opx) were only partly overgrown by hydrous minerals. Here, Cl-enriched minerals (Amph, Bt, Scp, Ap) can be observed. Amphibole shows compositions covering the range 0.1 - 4.0 wt % Cl within single thin sections. Mineral textures and extreme compositional variations of the Cl-bearing minerals indicate large chemical gradients of the fluid phase. Relics of primary mafic silicates and compositionally zoned reaction coronas around primary mafic silicates suggest that the free fluid was totally consumed before the alteration of the primary phases were completed. The extreme variations in the Cl-content of amphibole are inferred to monitor a gradual desiccation of the Cl-bearing grain-boundary fluid during fluid-mineral reactions accordingly: 1) The first amphibole that formed during the reactions principally extracted water from the fluid, resulting in a slight increase in the Cl content of the fluid. 2) Continued amphibole-forming reactions resulted in gradual consumption of the free fluid phase, principally by extracting water from the fluid, resulting in an increase in its Cl-content. Higher Cl-content of the fluid resulted in higher Cl-content of the equilibrium amphibole. 3) The most Cl-enriched amphibole (4 wt % Cl) formed in equilibrium with the last volumes of the grain-boundary fluid, which had evolved to a highly saline solution. Mineral reactions within a 1-2 thick zone of the host rock along the contact to the shear zones indicate a more complicated involvement of fluids during shear zone formation than described above. Apparently, fluids have been transported laterally from the outer parts of the shear zones into the gabbro-anorthosite along thin recrystallized zones of plagioclase. The fluid that infiltrated the undeformed host rock of the shear zones resulted in formation of Cl-free amphibole and garnet between the primary mafic minerals and plagioclase. A working hypothesis is that narrow fractures formed within the host rock, outside the sheared rock during shear zone formation. During shear zone formation, the central parts of the shear zones were completely hydrated by an externally derived Cl-bearing hydrous fluid. Some of the fluid migrated to the marginal parts of the shear zones and evolved to a highly saline solution. However, during desiccation of the fluid along the marginal parts of the shear zones, some of the fluid escaped along narrow fractures into the host rock of the shear zones. The Cl-free amphibole that formed from this fluid suggests that the narrow pathways of the fluid provided a path for water transport, but acted as a filter for the much larger ions of Cl.

Magnetic Fluids--Part 1.

ERIC Educational Resources Information Center

Hoon, S. R.; Tanner, B. K.

1985-01-01

Basic physical concepts of importance in understanding magnetic fluids (fine ferromagnetic particles suspended in a liquid) are discussed. They include home-made magnetic fluids, stable magnetic fluids, and particle surfactants. (DH)

Microgravity Transport Phenomena Experiment (MTPE) Overview

NASA Technical Reports Server (NTRS)

Mason, Larry W.

1999-01-01

The Microgravity Transport Phenomena Experiment (MTPE) is a fluids experiment supported by the Fundamentals in Biotechnology program in association with the Human Exploration and Development of Space (BEDS) initiative. The MTP Experiment will investigate fluid transport phenomena both in ground based experiments and in the microgravity environment. Many fluid transport processes are affected by gravity. Osmotic flux kinetics in planar membrane systems have been shown to be influenced by gravimetric orientation, either through convective mixing caused by unstably stratified fluid layers, or through a stable fluid boundary layer structure that forms in association with the membrane. Coupled transport phenomena also show gravity related effects. Coefficients associated with coupled transport processes are defined in terms of a steady state condition. Buoyancy (gravity) driven convection interferes with the attainment of steady state, and the measurement of coupled processes. The MTP Experiment measures the kinetics of molecular migration that occurs in fluids, in response to the application of various driving potentials. Three separate driving potentials may be applied to the MTP Experiment fluids, either singly or in combination. The driving potentials include chemical potential, thermal potential, and electrical potential. Two separate fluid arrangements are used to study membrane mediated and bulk fluid transport phenomena. Transport processes of interest in membrane mediated systems include diffusion, osmosis, and streaming potential. Bulk fluid processes of interest include coupled phenomena such as the Soret Effect, Dufour Effect, Donnan Effect, and thermal diffusion potential. MTP Experiments are performed in the Microgravity Transport Apparatus (MTA), an instrument that has been developed specifically for precision measurement of transport processes. Experiment fluids are contained within the MTA fluid cells, designed to create a one dimensional flow geometry of constant cross sectional area, and to facilitate fluid filling and draining operations in microgravity. The fluid cells may be used singly for bulk solutions, or in a Stokes diaphragm configuration to investigate membrane mediated phenomena. Thermal and electrical driving potentials are applied to the experiment fluids through boundary plates located at the ends of the fluid cells. In the ground based instrument, two constant temperature baths circulate through reservoirs adjacent to the boundary plates, and establish the thermal environment within the fluid cells. The boundary plates also serve as electrodes for measurement and application of electrical potentials. The Fluid Manipulation System associated with the MTA is a computer controlled system that enables storage and transfer of experiment fluids during on orbit operations. The system is used to automatically initiate experiments and manipulate fluids by orchestrating pump and valve operations through scripted sequences. Unique technologies are incorporated in the MTA for measurement of fluid properties. Volumetric Flow Sensors have been developed for precision measurement of total fluid volume contained within the fluid cells over time. This data is most useful for measuring the kinetics of osmosis, where fluid is transported from one fluid cell to another through a semipermeable membrane. The MicroSensor Array has been designed to perform in situ measurement of several important fluid parameters, providing simultaneous measurement of solution composition at multiple locations within the experiment fluids. Micromachined sensors and interface electronics have been developed to measure temperature, electrical conductivity, pH, cation activity, and anion activity. The Profile Refractometer uses a laser optical system to directly image the fluid Index of Refraction profile that exists along the MTA fluid cell axis. A video system acquires images of the RI profile over time, and records the transport kinetics that occur upon application of chemical, thermal, or electrical driving potentials. Image processing algorithms have been developed to analyze the refractometer images on a pixel by pixel basis, calibrating and scaling the measured Index of Refraction profile to correlated solution properties of interest such as density, concentration, and temperature. Additional software has been developed to compile the processed images into a three dimensional matrix that contains fluid composition data as a function of experiment time and position in the fluid cell. These data are combined with data from the other sensor systems, and analyzed in the context of transport coefficients associated with the various transport phenomena. Analysis protocols have been developed to measure the transient kinetics, and steady state distribution of fluid components that occur in response to the applied driving potentials. The results are expressed in terms of effective transport coefficients. Experiments have been performed using a variety of solutes, and results generated are that are in agreement with published transport coefficient values.

46 CFR 58.30-50 - Requirements for miscellaneous fluid power and control systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-50 Requirements for miscellaneous fluid power and control systems. (a) All fluid power and control... 46 Shipping 2 2010-10-01 2010-10-01 false Requirements for miscellaneous fluid power and control...

46 CFR 153.436 - Heat transfer fluids: compatibility with cargo.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 5 2012-10-01 2012-10-01 false Heat transfer fluids: compatibility with cargo. 153.436... Equipment Cargo Temperature Control Systems § 153.436 Heat transfer fluids: compatibility with cargo. A heat transfer fluid separated from the cargo by only one wall (for example, the heat transfer fluid in a coil...

46 CFR 153.436 - Heat transfer fluids: compatibility with cargo.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 5 2014-10-01 2014-10-01 false Heat transfer fluids: compatibility with cargo. 153.436... Equipment Cargo Temperature Control Systems § 153.436 Heat transfer fluids: compatibility with cargo. A heat transfer fluid separated from the cargo by only one wall (for example, the heat transfer fluid in a coil...

46 CFR 153.436 - Heat transfer fluids: compatibility with cargo.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 5 2013-10-01 2013-10-01 false Heat transfer fluids: compatibility with cargo. 153.436... Equipment Cargo Temperature Control Systems § 153.436 Heat transfer fluids: compatibility with cargo. A heat transfer fluid separated from the cargo by only one wall (for example, the heat transfer fluid in a coil...

46 CFR 58.30-50 - Requirements for miscellaneous fluid power and control systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-50 Requirements for miscellaneous fluid power and control systems. (a) All fluid power and control... 46 Shipping 2 2014-10-01 2014-10-01 false Requirements for miscellaneous fluid power and control...

46 CFR 153.436 - Heat transfer fluids: compatibility with cargo.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 5 2011-10-01 2011-10-01 false Heat transfer fluids: compatibility with cargo. 153.436... Equipment Cargo Temperature Control Systems § 153.436 Heat transfer fluids: compatibility with cargo. A heat transfer fluid separated from the cargo by only one wall (for example, the heat transfer fluid in a coil...

46 CFR 153.436 - Heat transfer fluids: compatibility with cargo.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Heat transfer fluids: compatibility with cargo. 153.436... Equipment Cargo Temperature Control Systems § 153.436 Heat transfer fluids: compatibility with cargo. A heat transfer fluid separated from the cargo by only one wall (for example, the heat transfer fluid in a coil...

Pitch-catch only ultrasonic fluid densitometer

DOEpatents

Greenwood, M.S.; Harris, R.V.

1999-03-23

The present invention is an ultrasonic fluid densitometer that uses a material wedge and pitch-catch only ultrasonic transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface. 6 figs.

Pitch-catch only ultrasonic fluid densitometer

DOEpatents

Greenwood, Margaret S.; Harris, Robert V.

1999-01-01

The present invention is an ultrasonic fluid densitometer that uses a material wedge and pitch-catch only ultrasonic transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface.

46 CFR 58.30-50 - Requirements for miscellaneous fluid power and control systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-50 Requirements for miscellaneous fluid power and control systems. (a) All fluid power and control... 46 Shipping 2 2013-10-01 2013-10-01 false Requirements for miscellaneous fluid power and control...

46 CFR 58.30-50 - Requirements for miscellaneous fluid power and control systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-50 Requirements for miscellaneous fluid power and control systems. (a) All fluid power and control... 46 Shipping 2 2011-10-01 2011-10-01 false Requirements for miscellaneous fluid power and control...

46 CFR 58.30-50 - Requirements for miscellaneous fluid power and control systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-50 Requirements for miscellaneous fluid power and control systems. (a) All fluid power and control... 46 Shipping 2 2012-10-01 2012-10-01 false Requirements for miscellaneous fluid power and control...

30 CFR 250.614 - Well-control fluids, equipment, and operations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... workover string, the annulus shall be filled with well-control fluid before the change in such fluid level... equivalent well-control fluid volume shall be calculated and posted near the operator's station. A mechanical... utilized: (1) A fill-up line above the uppermost BOP; (2) A well-control, fluid-volume measuring device for...

Selective evaporation of focusing fluid in two-fluid hydrodynamic print head.

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

Keicher, David M.; Cook, Adam W.

The work performed in this project has demonstrated the feasibility to use hydrodynamic focusing of two fluid steams to create a novel micro printing technology for electronics and other high performance applications. Initial efforts focused solely on selective evaporation of the sheath fluid from print stream provided insight in developing a unique print head geometry allowing excess sheath fluid to be separated from the print flow stream for recycling/reuse. Fluid flow models suggest that more than 81 percent of the sheath fluid can be removed without affecting the print stream. Further development and optimization is required to demonstrate this capabilitymore » in operation. Print results using two-fluid hydrodynamic focusing yielded a 30 micrometers wide by 0.5 micrometers tall line that suggests that the cross-section of the printed feature from the print head was approximately 2 micrometers in diameter. Printing results also demonstrated that complete removal of the sheath fluid is not necessary for all material systems. The two-fluid printing technology could enable printing of insulated conductors and clad optical interconnects. Further development of this concept should be pursued.« less

The origin of mouth-exhaled ammonia.

PubMed

Chen, W; Metsälä, M; Vaittinen, O; Halonen, L

2014-09-01

It is known that the oral cavity is a production site for mouth-exhaled NH3. However, the mechanism of NH3 production in the oral cavity has been unclear. Since bacterial urease in the oral cavity has been found to produce ammonia from oral fluid urea, we hypothesize that oral fluid urea is the origin of mouth-exhaled NH3. Our results show that under certain conditions a strong correlation exists between oral fluid urea and oral fluid ammonia (NH4(+)+NH3) (rs = 0.77, p < 0.001). We also observe a strong correlation between oral fluid NH3 and mouth-exhaled NH3 (rs = 0.81, p < 0.001). We conclude that three main factors affect the mouth-exhaled NH3 concentration: urea concentration, urease activity and oral fluid pH. Bacterial urease catalyses the hydrolysis of oral fluid urea to ammonia (NH4(+)+NH3). Oral fluid ammonia (NH4(+)+NH3) and pH determine the concentration of oral fluid NH3, which evaporates from oral fluid into gas phase and turns to mouth-exhaled NH3.

Pediatric Diabetic Ketoacidosis, Fluid Therapy and Cerebral Injury: The Design of a Factorial Randomized Controlled Trial

PubMed Central

Glaser, Nicole S.; Ghetti, Simona; Casper, T. Charles; Dean, J. Michael; Kuppermann, Nathan

2013-01-01

Treatment protocols for pediatric diabetic ketoacidosis (DKA) vary considerably among centers in the United States and worldwide. The optimal protocol for intravenous fluid administration is an area of particular controversy, mainly in regard to possible associations between rates of intravenous fluid infusion and the development of cerebral edema, the most common and most feared complication of DKA in children. Theoretical concerns about associations between osmotic fluid shifts and cerebral edema have prompted recommendations for conservative fluid infusion during DKA. However, recent data suggest that cerebral hypoperfusion may play a role in cerebral injury associated with DKA. Currently there are no existing data from prospective clinical trials to determine the optimal fluid treatment protocol for pediatric DKA. The Pediatric Emergency Care Applied Research Network FLUID (Fluid Therapies Under Investigation in DKA) Study is the first prospective randomized trial to evaluate fluid regimens for pediatric DKA. This 13-center nationwide factorial-design study will evaluate the effects of rehydration rate and fluid sodium content on neurological status during DKA treatment, the frequency of clinically-overt CE, and long-term neurocognitive outcomes following DKA. PMID:23490311

Fluid balance within the canine anterolateral compartment and its relationship to compartment syndromes.

PubMed

Hargens, A R; Akeson, W H; Mubarak, S J; Owen, C A; Evans, K L; Garetto, L P; Gonsalves, M R; Schmidt, D A

1978-06-01

Fluid homeostasis within muscle compartments is maintained by four pressures: capillary blood pressure, capillary blood oncotic pressure, tissue-fluid pressure, and tissue fluid oncotic pressure. As determined in the canine anterolateral compartment, capillary blood pressure is 25 +/- 3 millimeters of mercury; capillary blood oncotic pressure, 26 +/- 3 millimeters of mercury, tissue-pbessure, -2 +/- 2 millimeters of mercury; and tissue-fluid oncotic pressure, 11 +/- 1 millimeters of mercury. The wick technique allows direct measurement of tissue-fluid pressure in skeletal muscle and, with minor modifications, is adapted to collect microsamples of interstitial fluid for determinations of tissue-fluid oncotic pressure. The wick technique detects very slight fluctuations in intracompartmental pressure such as light finger compression, injection of small volumes of fluid, and even pulsation due to adjacent arterial pressure. Adjacent muscle compartments may contain different tissue-fluid pressure due to impermeable osseofascial barriers. Our results obtained in canine muscle compartments pressurized by infusion of autologous plasma suggest that risks of muscle damage are significant at intracompartmental pressures greater than thirty millimeters of mercury.

Numerical investigation of fluid mud motion using a three-dimensional hydrodynamic and two-dimensional fluid mud coupling model

NASA Astrophysics Data System (ADS)

Yang, Xiaochen; Zhang, Qinghe; Hao, Linnan

2015-03-01

A water-fluid mud coupling model is developed based on the unstructured grid finite volume coastal ocean model (FVCOM) to investigate the fluid mud motion. The hydrodynamics and sediment transport of the overlying water column are solved using the original three-dimensional ocean model. A horizontal two-dimensional fluid mud model is integrated into the FVCOM model to simulate the underlying fluid mud flow. The fluid mud interacts with the water column through the sediment flux, current, and shear stress. The friction factor between the fluid mud and the bed, which is traditionally determined empirically, is derived with the assumption that the vertical distribution of shear stress below the yield surface of fluid mud is identical to that of uniform laminar flow of Newtonian fluid in the open channel. The model is validated by experimental data and reasonable agreement is found. Compared with numerical cases with fixed friction factors, the results simulated with the derived friction factor exhibit the best agreement with the experiment, which demonstrates the necessity of the derivation of the friction factor.

Intravenous fluid prescription practices among pediatric residents in Korea.

PubMed

Lee, Jiwon M; Jung, Younghwa; Lee, Se Eun; Lee, Jun Ho; Kim, Kee Hyuck; Koo, Ja Wook; Park, Young Seo; Cheong, Hae Il; Ha, Il-Soo; Choi, Yong; Kang, Hee Gyung

2013-07-01

Recent studies have established the association between hypotonic fluids administration and hospital-acquired hyponatremia in children. The present paper investigated the pattern of current practice in intravenous fluid prescription among Korean pediatric residents, to underscore the need for updated education. A survey-based analysis was carried out. Pediatric residents at six university hospitals in Korea completed a survey consisting of four questions. Each question proposed a unique scenario in which the respondents had to prescribe either a hypotonic or an isotonic fluid for the patient. Ninety-one responses were collected and analyzed. In three of the four scenarios, a significant majority prescribed the hypotonic fluids (98.9%, 85.7%, and 69.2%, respectively). Notably, 69.2% of the respondents selected the hypotonic fluids for postoperative management. Almost all (96.7%) selected the isotonic fluids for hydration therapy. In the given scenarios, the majority of Korean pediatric residents would prescribe a hypotonic fluid, except for initial hydration. The current state of pediatric fluid management, notably, heightens the risk of hospital-acquired hyponatremia. Updated clinical practice education on intravenous fluid prescription, therefore, is urgently required.

Magnetic Fluid Friction and Wear Behavior

NASA Technical Reports Server (NTRS)

Keith, Theo G., Jr.

1998-01-01

The friction and wear properties of two groups of magnetic fluids, one developed at NASA Lewis Research Center and a commercial fluid, were evaluated for boundary lubrication. Friction and wear measurements were made using a pin-on-disk apparatus. Three different ball materials were evaluated, (1) 440C, (2) Al2O3, and (3) Si3N4 against 440C disks. The first class of magnetic fluids have a low vapor pressure hydrocarbon base oil and are suitable for space application. Four variations of this fluid were evaluated: (1) the base oil, (2) base oil with anti-wear additives, (3) a 100 Gauss strength magnetic fluid, and (4) a 400 gauss magnetic fluid. The commercial fluid base oil and four different magnetic particle concentration levels have been evaluated. A space qualified fluorinated lubricant was tested for base line comparison. Hardness, optical microscopy, surface profilometry, and surface analysis were used to characterize the test specimens. Friction was unaffected by the concentration of magnetic particles. Wear rates for magnetic fluids were slightly higher than the base oil. The low vapor pressure magnetic fluid has better wear characteristics than the space qualified fluorinated lubricant.

Ore-fluid evolution at the Getchell Carlin-type gold deposit, Nevada, USA

USGS Publications Warehouse

Cline, J.S.; Hofstra, A.A.

2000-01-01

Minerals and fluid-inclusion populations were examined using petrography, microthermometry, quadrupole mass-spectrometer gas analyses and stable-isotope studies to characterize fluids responsible for gold mineralization at the Getchell Carlin-type gold deposit. The gold-ore assemblage at Getchell is superimposed on quartz-pyrite vein mineralization associated with a Late-Cretaceous granodiorite stock that intruded Lower-Paleozoic sedimentary rocks. The ore assemblage, of mid-Tertiary age, consists of disseminated arsenian pyrite that contains submicrometer gold, jasperoid quartz, and later fluorite and orpiment that fill fractures and vugs. Late ore-stage realgar and calcite enclose ore-stage minerals. Pre-ore quartz trapped fluids with a wide range of salinities (1 to 21 wt.% NaCl equivalent), gas compositions (H2O, CO2, and CH4), and temperatures (120 to >360??C). Oxygen- and hydrogen-isotope ratios indicate that pre-ore fluids likely had a magmatic source, and were associated with intrusion of the granodiorite stock and related dikes. Ore-stage jasperoid contains moderate salinity, aqueous fluid inclusions trapped at 180 to 220??C. Ore fluids contain minor CO2 and trace H2S that allowed the fluid to react with limestone host rocks and transport gold, respectively. Aqueous inclusions in fluorite indicate that fluid temperatures declined to ~175??C by the end of ore-stage mineralization. As the hydrothermal system collapsed, fluid temperatures declined to 155 to 115??C and realgar and calcite precipitated. Inclusion fluids in ore-stage minerals have high ??D(H2O) and ??18O(H2O) values that indicate that the fluid had a deep source, and had a metamorphic or magmatic origin, or both. Late ore-stage fluids extend to lower ??D(H2O) values, and have a wider range of ??18O(H2O) values suggesting dilution by variably exchanged meteoric waters. Results show that deeply sourced ore fluids rose along the Getchell fault system, where they dissolved carbonate wall rocks and deposited gold-enriched pyrite and jasperoid quartz. Gold and pyrite precipitated together as H2S in the ore fluids reacted with iron in the host rocks. As ore fluids mixed with local aquifer fluids, ore fluids became cooler and more dilute. Cooling caused precipitation of ore-stage fluorite and orpiment, and late ore-stage realgar. Phase separation and/or neutralization of the ore fluid during the waning stages of the hydrothermal ore system led to deposition of late ore-stage calcite.

Fluid-structure finite-element vibrational analysis

NASA Technical Reports Server (NTRS)

Feng, G. C.; Kiefling, L.

1974-01-01

A fluid finite element has been developed for a quasi-compressible fluid. Both kinetic and potential energy are expressed as functions of nodal displacements. Thus, the formulation is similar to that used for structural elements, with the only differences being that the fluid can possess gravitational potential, and the constitutive equations for fluid contain no shear coefficients. Using this approach, structural and fluid elements can be used interchangeably in existing efficient sparse-matrix structural computer programs such as SPAR. The theoretical development of the element formulations and the relationships of the local and global coordinates are shown. Solutions of fluid slosh, liquid compressibility, and coupled fluid-shell oscillation problems which were completed using a temporary digital computer program are shown. The frequency correlation of the solutions with classical theory is excellent.

Caractérisation géochimique des fluides associés aux minéralisations Pb sbnd Zn de Bou-Dahar (Maroc)

NASA Astrophysics Data System (ADS)

Adil, Samira; Bouabdellah, Mohammed; Grandia, Fidel; Cardellach, Esteve; Canals, Àngel

2004-11-01

The Bou-Dahar Pb sbnd Zn Mississippi Valley deposits located in the eastern part of the High Atlas Range (Morocco) are hosted by a Liassic reefal complex. Fluid inclusion and 'crush-leach' data show that two distinct fluids were involved in the mineralisation deposition: a warmer, more saline fluid (180 °C, >25 wt% NaCl equivalent) and a cooler, less saline fluid (70 °C, 16 wt% equivalent NaCl). Mixing of these two fluids resulted in the precipitation of the ore. The solute composition of the ore-forming brine suggests that the MVT mineralising fluids were probably a mixture of halite-dissolution fluids and evaporated seawater. To cite this article: S. Adil et al., C. R. Geoscience 336 (2004).

Portable Medical Diagnosis Instrument

NASA Technical Reports Server (NTRS)

Coleman, Matthew A. (Inventor); Straume, Tore (Inventor); Loftus, David J. (Inventor); Li, Jing (Inventor); Singh, Anup K. (Inventor); Davis, Cristina E. (Inventor)

2017-01-01

A system that integrates several technologies into a single, portable medical diagnostic apparatus for analyzing a sample body fluid (liquid and/or gas): (1) a mechanism to capture airborne microdroplets and to separate the body fluid into a first fluid component (primarily gas) and a second fluid component (primarily liquid); (2) a volatilizer to convert a portion of the second fluid component into a third fluid component that is primarily a gas; (3) a functionalized nanostructure (NS) array configured to receive, identify, and estimate concentration of at least one constituent in the first and/or third fluid components; (4) a miniaturized differential mobility spectrometer (DMS) module; and (5) a biomarker sensor, to detect volatile and non-volatile molecules in a sample fluid, which may contain one or more components of blood, breath, perspiration, saliva, and urine.

Controlled differential pressure system for an enhanced fluid blending apparatus

DOEpatents

Hallman, Jr., Russell Louis

2009-02-24

A system and method for producing a controlled blend of two or more fluids. Thermally-induced permeation through a permeable tube is used to mix a first fluid from outside the tube with a second fluid flowing through the tube. Mixture ratios may be controlled by adjusting the temperature of the first fluid or by adjusting the pressure drop through the permeable tube. The combination of a back pressure control valve and a differential regulator is used to control the output pressure of the blended fluid. The combination of the back pressure control valve and differential regulator provides superior flow control of the second dry gas. A valve manifold system may be used to mix multiple fluids, and to adjust the volume of blended fluid produced, and to further modify the mixture ratio.

Guiding principles of fluid and volume therapy.

PubMed

Aditianingsih, Dita; George, Yohanes W H

2014-09-01

Fluid therapy is a core concept in the management of perioperative and critically ill patients for maintenance of intravascular volume and organ perfusion. Recent evidence regarding the vascular barrier and its role in terms of vascular leakage has led to a new concept for fluid administration. The choice of fluid used should be based on the fluid composition and the underlying pathophysiology of the patient. Avoidance of both hypo- and hypervolaemia is essential when treating circulatory failure. In daily practice, the assessment of individual thresholds in order to optimize cardiac preload and avoid hypovolaemia or deleterious fluid overload remains a challenge. Liberal versus restrictive fluid management has been challenged by recent evidence, and the ideal approach appears to be goal-directed fluid therapy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Upper mantle fluids evolution, diamond formation, and mantle metasomatism

NASA Astrophysics Data System (ADS)

Huang, F.; Sverjensky, D. A.

2017-12-01

During mantle metasomatism, fluid-rock interactions in the mantle modify wall-rock compositions. Previous studies usually either investigated mineral compositions in xenoliths and xenocrysts brought up by magmas, or examined fluid compositions preserved in fluid inclusions in diamonds. However, a key study of Panda diamonds analysed both mineral and fluid inclusions in the diamonds [1] which we used to develop a quantitative characterization of mantle metasomatic processes. In the present study, we used an extended Deep Earth Water model [2] to simulate fluid-rock interactions at upper mantle conditions, and examine the fluids and mineral assemblages together simultaneously. Three types of end-member fluids in the Panda diamond fluid inclusions include saline, rich in Na+K+Cl; silicic, rich in Si+Al; and carbonatitic, rich in Ca+Mg+Fe [1, 3]. We used the carbonatitic end-member to represent fluid from a subducting slab reacting with an excess of peridotite + some saline fluid in the host environment. During simultaneous fluid mixing and reaction with the host rock, the logfO2 increased by about 1.6 units, and the pH increased by 0.7 units. The final minerals were olivine, garnet and diamond. The Mg# of olivine decreased from 0.92 to 0.85. Garnet precipitated at an early stage, and its Mg# also decreased with reaction progress, in agreement with the solid inclusions in the Panda diamonds. Phlogopite precipitated as an intermediate mineral and then disappeared. The aqueous Ca, Mg, Fe, Si and Al concentrations all increased, while Na, K, and Cl concentrations decreased during the reaction, consistent with trends in the fluid inclusion compositions. Our study demonstrates that fluids coming from subducting slabs could trigger mantle metasomatism, influence the compositions of sub-lithospherc cratonic mantle, precipitate diamonds, and change the oxygen fugacity and pH of the upper mantle fluids. [1] Tomlinson et al. EPSL (2006); [2] Sverjensky, DA et al., GCA (2014), Huang, F, Ph. D. thesis, Johns Hopkins University, (2017); [3] Shirey et al., Rev. Mineral. Geochem. (2013)

Pore fluid pressure and the seismic cycle

NASA Astrophysics Data System (ADS)

French, M. E.; Zhu, W.; Hirth, G.; Belzer, B.

2017-12-01

In the brittle crust, the critical shear stress required for fault slip decreases with increasing pore fluid pressures according to the effective stress criterion. As a result, higher pore fluid pressures are thought to promote fault slip and seismogenesis, consistent with observations that increasing fluid pressure as a result of wastewater injection is correlated with increased seismicity. On the other hand, elevated pore fluid pressure is also proposed to promote slow stable failure rather than seismicity along some fault zones, including during slow slip in subduction zones. Here we review recent experimental evidence for the roles that pore fluid pressure and the effective stress play in controlling fault slip behavior. Using two sets of experiments on serpentine fault gouge, we show that increasing fluid pressure does decrease the shear stress for reactivation under brittle conditions. However, under semi-brittle conditions as expected near the base of the seismogenic zone, high pore fluid pressures are much less effective at reducing the shear stress of reactivation even though deformation is localized and frictional. We use an additional study on serpentinite to show that cohesive fault rocks, potentially the product of healing and cementation, experience an increase in fracture energy during faulting as fluid pressures approach lithostatic, which can lead to more stable failure. Structural observations show that the increased fracture energy is associated with a greater intensity of transgranular fracturing and delocalization of deformation. Experiments on several lithologies indicate that the stabilizing effect of fluid pressure occurs independent of rock composition and hydraulic properties. Thus, high pore fluid pressures have the potential to either enhance seismicity or promote stable faulting depending on pressure, temperature, and fluid pressure conditions. Together, the results of these studies indicate that pore fluid pressure promotes seismogenesis in the brittle shallow crust where fluid pressures are elevated but sub-lithostatic and promote slow, stable failure near seismic to aseismic transitions and under near-lithostatic fluid pressures.

Links between fluid circulation, temperature, and metamorphism in subducting slabs

USGS Publications Warehouse

Spinelli, G.A.; Wang, K.

2009-01-01

The location and timing of metamorphic reactions in subducting lithosph??re are influenced by thermal effects of fluid circulation in the ocean crust aquifer. Fluid circulation in subducting crust extracts heat from the Nankai subduction zone, causing the crust to pass through cooler metamorphic faci??s than if no fluid circulation occurs. This fluid circulation shifts the basalt-to-eclogite transition and the associated slab dehydration 14 km deeper (35 km farther landward) than would be predicted with no fluid flow. For most subduction zones, hydrothermal cooling of the subducting slab will delay eclogitization relative to estimates made without considering fluid circulation. Copyright 2009 by the American Geophysical Union.

Flow Diode and Method for Controlling Fluid Flow Origin of the Invention

NASA Technical Reports Server (NTRS)

Dyson, Rodger W (Inventor)

2015-01-01

A flow diode configured to permit fluid flow in a first direction while preventing fluid flow in a second direction opposite the first direction is disclosed. The flow diode prevents fluid flow without use of mechanical closures or moving parts. The flow diode utilizes a bypass flowline whereby all fluid flow in the second direction moves into the bypass flowline having a plurality of tortuous portions providing high fluidic resistance. The portions decrease in diameter such that debris in the fluid is trapped. As fluid only travels in one direction through the portions, the debris remains trapped in the portions.

Intravenous maintenance fluid therapy in children.

PubMed

McNab, Sarah

2016-02-01

Intravenous fluids are frequently used in paediatrics but have been associated with significant adverse outcomes. Understanding the composition of fluid prescribed and administering an appropriate rate is essential for safe fluid administration, along with regular monitoring. Recent evidence has shown that using an isotonic fluid with a sodium concentration similar to plasma can decrease the risk of hyponatraemia without an increase in adverse effects. This should lead to a change in guidelines: isotonic fluid should now be used as the primary maintenance intravenous fluid given to the majority of children. © 2016 The Author Journal of Paediatrics and Child Health © 2016 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

Method of absorbance correction in a spectroscopic heating value sensor

DOEpatents

Saveliev, Alexei; Jangale, Vilas Vyankatrao; Zelepouga, Sergeui; Pratapas, John

2013-09-17

A method and apparatus for absorbance correction in a spectroscopic heating value sensor in which a reference light intensity measurement is made on a non-absorbing reference fluid, a light intensity measurement is made on a sample fluid, and a measured light absorbance of the sample fluid is determined. A corrective light intensity measurement at a non-absorbing wavelength of the sample fluid is made on the sample fluid from which an absorbance correction factor is determined. The absorbance correction factor is then applied to the measured light absorbance of the sample fluid to arrive at a true or accurate absorbance for the sample fluid.

Intrinsically safe moisture blending system

DOEpatents

Hallman Jr., Russell L.; Vanatta, Paul D.

2012-09-11

A system for providing an adjustable blend of fluids to an application process is disclosed. The system uses a source of a first fluid flowing through at least one tube that is permeable to a second fluid and that is disposed in a source of the second fluid to provide the adjustable blend. The temperature of the second fluid is not regulated, and at least one calibration curve is used to predict the volumetric mixture ratio of the second fluid with the first fluid from the permeable tube. The system typically includes a differential pressure valve and a backpressure control valve to set the flow rate through the system.

Association Between Fluid Balance and Outcomes in Critically Ill Children: A Systematic Review and Meta-analysis.

PubMed

Alobaidi, Rashid; Morgan, Catherine; Basu, Rajit K; Stenson, Erin; Featherstone, Robin; Majumdar, Sumit R; Bagshaw, Sean M

2018-03-01

After initial resuscitation, critically ill children may accumulate fluid and develop fluid overload. Accruing evidence suggests that fluid overload contributes to greater complexity of care and worse outcomes. To describe the methods to measure fluid balance, define fluid overload, and evaluate the association between fluid balance and outcomes in critically ill children. Systematic search of MEDLINE, EMBASE, Cochrane Library, trial registries, and selected gray literature from inception to March 2017. Studies of children admitted to pediatric intensive care units that described fluid balance or fluid overload and reported outcomes of interest were included. No language restrictions were applied. All stages were conducted independently by 2 reviewers. Data extracted included study characteristics, population, fluid metrics, and outcomes. Risk of bias was assessed using the Newcastle-Ottawa Scale. Narrative description of fluid assessment methods and fluid overload definitions was done. When feasible, pooled analyses were performed using random-effects models. Mortality was the primary outcome. Secondary outcomes included treatment intensity, organ failure, and resource use. A total of 44 studies (7507 children) were included in this systematic review and meta-analysis. Of those, 27 (61%) were retrospective cohort studies, 13 (30%) were prospective cohort studies, 3 (7%) were case-control studies, and 1 study (2%) was a secondary analysis of a randomized trial. The proportion of children with fluid overload varied by case mix and fluid overload definition (median, 33%; range, 10%-83%). Fluid overload, however defined, was associated with increased in-hospital mortality (17 studies [n = 2853]; odds ratio [OR], 4.34 [95% CI, 3.01-6.26]; I2 = 61%). Survivors had lower percentage fluid overload than nonsurvivors (22 studies [n = 2848]; mean difference, -5.62 [95% CI, -7.28 to -3.97]; I2 = 76%). After adjustment for illness severity, there was a 6% increase in odds of mortality for every 1% increase in percentage fluid overload (11 studies [n = 3200]; adjusted OR, 1.06 [95% CI, 1.03-1.10]; I2 = 66%). Fluid overload was associated with increased risk for prolonged mechanical ventilation (>48 hours) (3 studies [n = 631]; OR, 2.14 [95% CI, 1.25-3.66]; I2 = 0%) and acute kidney injury (7 studies [n = 1833]; OR, 2.36 [95% CI, 1.27-4.38]; I2 = 78%). Fluid overload is common and is associated with substantial morbidity and mortality in critically ill children. Additional research should now ideally focus on interventions aimed to mitigate the potential for harm associated with fluid overload.

Metallogeny by Trans-magmatic Fluids—Theoretical Analysis and Field Evidence

NASA Astrophysics Data System (ADS)

Luo, Zhaohua; Mo, Xuanxue; Lu, Xinxiang; Chen, Bihe; Ke, Shan; Hou, Zengqian; Jiang, Wan

This paper is aimed at introducing and developing the principle of Metallogenic Theory through Trans-magmatic Fluids (MTTF) proposed by the Russian Kozhinskii's school. Some fundamental problems of metallogeny are discussed on geodynamic bases. In this theory, the trans-magmatic fluid is interpreted as a moving fluid passing through magma which is not yet consolidated. The intensive wallrock alteration of most of hydrothermal ore systems suggests that large scale fluid flow accompanies metallogenesis. However, geological observations and experiments imply a very limited solubility of fluids in magmas. In addition, the close relationship between small igneous bodies and large ore systems together with the difficulty of fluids that from the wallrocks might enter a magmatic body, which is under high pressure and temperature, need also to be considered. Those ore-bearing fluids that originate from a deep fluid system, are independent of magmas. Experiments show rapid increases of the solubility of ore-forming elements or their compounds in hydrothermal fluids. Therefore, the essential prerequisites for mineralization are (1) large volumes of deep ore-bearing fluids with high concentration of metals, and (2) the large amounts of metal accumulation depend on the rapid ascent of the deep ore-bearing fluid. Magmas are the favorable medium for the ascending fluids, because these magmas provide conditions that prevent re-equilibrium between the fluid and the wallrocks at different deep levels. The fluids in turn, may provide the driving force for the rapid ascent of magmas. Therefore, the two systems act together to account for the close relationship between magmatism and metallogeny. According to this theory, the scale and location of an ore-forming process are decided by (1) the volumetric ratio of the magma and the fluid systems, (2) the ascending rate of the ore-bearing fluid, (3) the boundary conditions for metal accumulation and (4) the segregation of the fluid from the magma. The field investigations of copper-bearing Melanocratic Macrogranular Enclaves (MME) in the Qushui massif, Gangdise belt are very helpful for understanding of source, transport and precipitation of ore-forming materials. In this example, it can be seen that fluid-rich MMEs is the source of the ore-forming element copper. Copper is transported out from MMEs by the fluid, following dispersal in the granitic magma. The copper-bearing fluid is then transferred through the magma and induced to deposit mineralization elsewhere. These processes have been noted when comparing the metallogenic features in both MME in the Qushui massif and the porphyry copper deposits in Yulong, eastern Tibet. It is obvious that MTTF is a very important theory for metallogeny of endogenic deposits. Using this theory, many paradoxes in metallogenesis can be interpreted in easier manner.

Fluid Therapy Management in Hospitalized Patients: Results From a Cross-sectional Study.

PubMed

Brugnolli, Anna; Canzan, Federica; Bevilacqua, Anita; Marognolli, Oliva; Verlato, Giuseppe; Vincenzi, Silvia; Ambrosi, Elisa

2017-02-01

Intravenous (IV) fluid therapy is widely used in hospitalized patients. It has been internationally studied in surgical patients, but little attention to date has been dedicated to medical patients within the Italian context. The aims of the present study were to describe the prevalence of fluid therapy and associated factors among Italian patients admitted to medical and surgical units, describe the methods used to manage fluid therapy, and analyze the monitoring of patients by clinical staff. In this cross-sectional study of 7 hospitals in northern Italy, data on individual and monitoring variables were collected, and their associations with in-hospital fluid therapy were analyzed by using logistic regression analysis. Patients aged ≥18 years who were admitted to medical and surgical units were included. Patients who received at least 500 mL of continuous fluids were included in the fluid therapy group. In total, 785 (median age, 72 years; women, 52%) patients were included in the study, and 293 (37.3%) received fluid therapy. Maintenance was the most frequent reason for prescribing IV fluid therapy (59%). The mean (SD) volume delivered was 1177 (624) mL/d, and the highest volume was infused for replacement therapy (1660 [931] mL/d). The mean volume infused was 19.55 (13) mL/kg/d. The most commonly used fluid solutions were 0.9% sodium chloride (65.7%) and balanced crystalloid without glucose (32.9%). The proportion of patients assessed for urine output (52.6% vs 36.8%; P < 0.001), serum electrolyte concentrations (74.4% vs 65.0%; P = 0.005), and renal function (70.0% vs 58.7%; P = 0.002) was significantly higher in patients who did receive fluid therapy versus those who did not. In contrast, the use of weight and fluid assessments was not significantly different between the 2 groups (P = 0.216 and 0.256, respectively). Patients admitted for gastrointestinal disorders (odds ratio [OR], 3.5 [95% CI, 1.8-7.05) and for fluid/electrolyte imbalances (OR, 3.35 [95% CI, 1.06-10.52) were more likely to receive fluids. However, the likelihood of receiving fluids was lower for patients admitted to a surgical unit (OR, 0.36 [95% CI, 0.22-0.59]) and with cardiovascular diseases (OR, 0.37 [95% CI, 0.17-0.79). Only one third of the study patients received fluid therapy. Crystalloid fluids, are the fluids of choice for maintaining plasma volume. During fluid therapy, measurement of the serum electrolyte concentrations, renal function, and urine output was largely used while weight and fluid balance were rarely assessed. Copyright © 2017 Elsevier HS Journals, Inc. All rights reserved.

Fluid accumulation during acute kidney injury in the intensive care unit.

PubMed

Berthelsen, R E; Perner, A; Jensen, A K; Jensen, J-U; Bestle, M H

2018-07-01

Fluid therapy is a ubiquitous intervention in patients admitted to the intensive care unit, but positive fluid balance may be associated with poor outcomes and particular in patients with acute kidney injury. Studies describing this have defined fluid overload either at specific time points or considered patients with a positive mean daily fluid balance as fluid overloaded. We wished to detail this further and performed joint model analyses of the association between daily fluid balance and outcome represented by mortality and renal recovery in patients admitted with acute kidney injury. We did a retrospective cohort study of patients admitted to the intensive care unit with acute kidney injury during a 2-year observation period. We used serum creatinine measurements to identify patients with acute kidney injury and collected sequential daily fluid balance during the first 5 days of admission to the intensive care unit. We used joint modelling techniques to correlate the development of fluid overload with survival and renal recovery adjusted for age, gender and disease severity. The cohort contained 863 patients with acute kidney injury of whom 460 (53%) and 254 (29%) developed 5% and 10% fluid overload, respectively. We found that both 5% and 10% fluid overload was correlated with reduced survival and renal recovery. Joint model analyses of fluid accumulation in patients admitted to the intensive care unit with acute kidney injury confirm that even a modest degree of fluid overload (5%) may be negatively associated with both survival and renal recovery. © 2018 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Fluid Pressures at the Shoe-Floor-Contaminant Interface During Slips: Effects of Tread & Implications on Slip Severity

PubMed Central

Beschorner, Kurt E.; Albert, Devon L.; Chambers, April J.; Redfern, Mark S.

2018-01-01

Previous research on slip and fall accidents has suggested that pressurized fluid between the shoe and floor is responsible for initiating slips yet this effect has not been verified experimentally. This study aimed to 1) measure hydrodynamic pressures during slipping for treaded and untreaded conditions; 2) determine the effects of fluid pressure on slip severity; and 3) quantify how fluid pressures vary with instantaneous resultant slipping speed, position on the shoe surface, and throughout the progression of the slip. Eighteen subjects walked on known dry and unexpected slippery floors, while wearing treaded and untreaded shoes. Fluid pressure sensors, embedded in the floor, recorded hydrodynamic pressures during slipping. The maximum fluid pressures (mean+/−standard deviation) were significantly higher for the untreaded conditions (124 +/−75 kPa) than the treaded conditions (1.1 +/−0.29 kPa). Maximum fluid pressures were positively correlated with peak slipping speed (r = 0.87), suggesting that higher fluid pressures, which are associated with untreaded conditions, resulted in more severe slips. Instantaneous resultant slipping speed and position of sensor relative to the shoe sole and walking direction explained 41% of the fluid pressure variability. Fluid pressures were primarily observed for untreaded conditions. This study confirms that fluid pressures are relevant to slipping events, consistent with fluid dynamics theory (i.e. the Reynolds equation), and can be modified with shoe tread design. The results suggest that the occurrence and severity of unexpected slips can be reduced by designing shoes/floors that reduce underfoot fluid pressures. PMID:24267270

The Effect of Boiling on Seismic Properties of Water-Saturated Fractured Rock

NASA Astrophysics Data System (ADS)

Grab, Melchior; Quintal, Beatriz; Caspari, Eva; Deuber, Claudia; Maurer, Hansruedi; Greenhalgh, Stewart

2017-11-01

Seismic campaigns for exploring geothermal systems aim at detecting permeable formations in the subsurface and evaluating the energy state of the pore fluids. High-enthalpy geothermal resources are known to contain fluids ranging from liquid water up to liquid-vapor mixtures in regions where boiling occurs and, ultimately, to vapor-dominated fluids, for instance, if hot parts of the reservoir get depressurized during production. In this study, we implement the properties of single- and two-phase fluids into a numerical poroelastic model to compute frequency-dependent seismic velocities and attenuation factors of a fractured rock as a function of fluid state. Fluid properties are computed while considering that thermodynamic interaction between the fluid phases takes place. This leads to frequency-dependent fluid properties and fluid internal attenuation. As shown in a first example, if the fluid contains very small amounts of vapor, fluid internal attenuation is of similar magnitude as attenuation in fractured rock due to other mechanisms. In a second example, seismic properties of a fractured geothermal reservoir with spatially varying fluid properties are calculated. Using the resulting seismic properties as an input model, the seismic response of the reservoir is then computed while the hydrothermal structure is assumed to vary over time. The resulting seismograms demonstrate that anomalies in the seismic response due to fluid state variability are small compared to variations caused by geological background heterogeneity. However, the hydrothermal structure in the reservoir can be delineated from amplitude anomalies when the variations due to geology can be ruled out such as in time-lapse experiments.

Acute Lung Injury Edema Fluid Decreases Net Fluid Transport across Human Alveolar Epithelial Type II Cells*

PubMed Central

Lee, Jae W.; Fang, Xiaohui; Dolganov, Gregory; Fremont, Richard D.; Bastarache, Julie A.; Ware, Lorraine B.; Matthay, Michael A.

2009-01-01

Most patients with acute lung injury (ALI) have reduced alveolar fluid clearance that has been associated with higher mortality. Several mechanisms may contribute to the decrease in alveolar fluid clearance. In this study, we tested the hypothesis that pulmonary edema fluid from patients with ALI might reduce the expression of ion transport genes responsible for vectorial fluid transport in primary cultures of human alveolar epithelial type II cells. Following exposure to ALI pulmonary edema fluid, the gene copy number for the major sodium and chloride transport genes decreased. By Western blot analyses, protein levels of αENaC, α1Na,K-ATPase, and cystic fibrosis transmembrane conductance regulator decreased as well. In contrast, the gene copy number for several inflammatory cytokines increased markedly. Functional studies demonstrated that net vectorial fluid transport was reduced for human alveolar type II cells exposed to ALI pulmonary edema fluid compared with plasma (0.02±0.05 versus 1.31±0.56 μl/cm2/h, p<0.02). An inhibitor of p38 MAPK phosphorylation (SB202190) partially reversed the effects of the edema fluid on net fluid transport as well as gene and protein expression of the main ion transporters. In summary, alveolar edema fluid from patients with ALI induced a significant reduction in sodium and chloride transport genes and proteins in human alveolar epithelial type II cells, effects that were associated with a decrease in net vectorial fluid transport across human alveolar type II cell monolayers. PMID:17580309

Ball assisted device for analytical surface sampling

DOEpatents

ElNaggar, Mariam S; Van Berkel, Gary J; Covey, Thomas R

2015-11-03

A system for sampling a surface includes a sampling probe having a housing and a socket, and a rolling sampling sphere within the socket. The housing has a sampling fluid supply conduit and a sampling fluid exhaust conduit. The sampling fluid supply conduit supplies sampling fluid to the sampling sphere. The sampling fluid exhaust conduit has an inlet opening for receiving sampling fluid carried from the surface by the sampling sphere. A surface sampling probe and a method for sampling a surface are also disclosed.

On the performance of finite journal bearings lubricated with micropolar fluids

NASA Technical Reports Server (NTRS)

Khonsari, M. M.; Brewe, D. E.

1988-01-01

A study of the performance parameters for a journal bearing of finite length lubricated with micropolar fluids is undertaken. Results indicate that a significantly higher load carrying capacity than the Newtonian fluids may result depending on the size of material characteristic length and the coupling number. It is also shown that although the frictional force associated with micropolar fluid is in general higher than that of a Newtonian fluid, the friction coefficient of micropolar fluids tends to be lower than that of the Newtonian.

On the performance of finite journal bearings lubricated with micropolar fluids

NASA Technical Reports Server (NTRS)

Khonsari, M. M.; Brewe, D. E.

1989-01-01

A study of the performance parameters for a journal bearing of finite length lubricated with micropolar fluids is undertaken. Results indicate that a significantly higher load carrying capacity than the Newtonian fluids may result depending on the size of material characteristics length and the coupling number. It is also shown that although the frictional force associated with micropolar fluid is, in general, higher than that of a Newtonian fluid, the friction coefficient of micropolar fluids tends to be lower than that of the Newtonian.

Phase-Controlled Bistability of a Dark Soliton Train in a Polariton Fluid.

PubMed

Goblot, V; Nguyen, H S; Carusotto, I; Galopin, E; Lemaître, A; Sagnes, I; Amo, A; Bloch, J

2016-11-18

We use a one-dimensional polariton fluid in a semiconductor microcavity to explore the nonlinear dynamics of counterpropagating interacting Bose fluids. The intrinsically driven-dissipative nature of the polariton fluid allows us to use resonant pumping to impose a phase twist across the fluid. When the polariton-polariton interaction energy becomes comparable to the kinetic energy, linear interference fringes transform into a train of solitons. A novel type of bistable behavior controlled by the phase twist across the fluid is experimentally evidenced.

Fluid bed material transfer method

DOEpatents

Pinske, Jr., Edward E.

1994-01-01

A fluidized bed apparatus comprising a pair of separated fluid bed enclosures, each enclosing a fluid bed carried on an air distributor plate supplied with fluidizing air from below the plate. At least one equalizing duct extending through sidewalls of both fluid bed enclosures and flexibly engaged therewith to communicate the fluid beds with each other. The equalizing duct being surrounded by insulation which is in turn encased by an outer duct having expansion means and being fixed between the sidewalls of the fluid bed enclosures.

Heat transfer fluids containing nanoparticles

DOEpatents

Singh, Dileep; Routbort, Jules; Routbort, A.J.; Yu, Wenhua; Timofeeva, Elena; Smith, David S.; France, David M.

2016-05-17

A nanofluid of a base heat transfer fluid and a plurality of ceramic nanoparticles suspended throughout the base heat transfer fluid applicable to commercial and industrial heat transfer applications. The nanofluid is stable, non-reactive and exhibits enhanced heat transfer properties relative to the base heat transfer fluid, with only minimal increases in pumping power required relative to the base heat transfer fluid. In a particular embodiment, the plurality of ceramic nanoparticles comprise silicon carbide and the base heat transfer fluid comprises water and water and ethylene glycol mixtures.

Automobile windshield washer fluid: A potential source of transmission for Legionella.

PubMed

Schwake, David Otto; Alum, Absar; Abbaszadegan, Morteza

2015-09-01

Epidemiological evidence suggesting driving cars to be a risk factor for legionellosis has prompted public health studies to investigate vehicle windshield washer fluid as a novel transmission source of this disease. The goal of the current study was to investigate whether or not windshield washer fluid could serve as a potential source of transmission for Legionella. A wide variation in the survival of L. pneumophila was observed when incubated in different washer fluids at 25 and 37 °C, however, one brand tested supported Legionella survival similar to or greater than sterilized deionized water. In addition, 1 L of tap water contained in a washer fluid reservoir was able to support population growth and survival of Legionella for several months. In a field study examining the windshield washer fluid of 12 elementary school buses, Legionella were detected from 84% of samples at a high concentration of 8.1×10(4) CFU/mL. Culturable cells were also detected in aerosolized washer fluid during washer fluid spray. By demonstrating survival in certain windshield washer fluids, growth within washer fluid reservoirs, and the presence of viable cells in bus washer fluid spray, we have provided evidence suggesting the potential for a novel route of Legionella exposure. Copyright © 2015 Elsevier B.V. All rights reserved.

Environmental Stability and Infectivity of Hepatitis C Virus (HCV) in Different Human Body Fluids.

PubMed

Pfaender, Stephanie; Helfritz, Fabian A; Siddharta, Anindya; Todt, Daniel; Behrendt, Patrick; Heyden, Julia; Riebesehl, Nina; Willmann, Wiebke; Steinmann, Joerg; Münch, Jan; Ciesek, Sandra; Steinmann, Eike

2018-01-01

Background: Hepatitis C virus (HCV) is a hepatotropic, blood-borne virus, but in up to one-third of infections of the transmission route remained unidentified. Viral genome copies of HCV have been identified in several body fluids, however, non-parental transmission upon exposure to contaminated body fluids seems to be rare. Several body fluids, e.g., tears and saliva, are renowned for their antimicrobial and antiviral properties, nevertheless, HCV stability has never been systematically analyzed in those fluids. Methods: We used state of the art infectious HCV cell culture techniques to investigate the stability of HCV in different body fluids to estimate the potential risk of transmission via patient body fluid material. In addition, we mimicked a potential contamination of HCV in tear fluid and analyzed which impact commercially available contact lens solutions might have in such a scenario. Results: We could demonstrate that HCV remains infectious over several days in body fluids like tears, saliva, semen, and cerebrospinal fluid. Only hydrogen-peroxide contact lens solutions were able to efficiently inactivate HCV in a suspension test. Conclusion: These results indicate that HCV, once it is present in various body fluids of infected patients, remains infective and could potentially contribute to transmission upon direct contact.

Mechanisms of fluid production in smooth adhesive pads of insects

PubMed Central

Dirks, Jan-Henning; Federle, Walter

2011-01-01

Insect adhesion is mediated by thin fluid films secreted into the contact zone. As the amount of fluid affects adhesive forces, a control of secretion appears probable. Here, we quantify for the first time the rate of fluid secretion in adhesive pads of cockroaches and stick insects. The volume of footprints deposited during consecutive press-downs decreased exponentially and approached a non-zero steady state, demonstrating the presence of a storage volume. We estimated its size and the influx rate into it from a simple compartmental model. Influx was independent of step frequency. Fluid-depleted pads recovered maximal footprint volumes within 15 min. Pads in stationary contact accumulated fluid along the perimeter of the contact zone. The initial fluid build-up slowed down, suggesting that flow is driven by negative Laplace pressure. Freely climbing stick insects left hardly any traceable footprints, suggesting that they save secretion by minimizing contact area or by recovering fluid during detachment. However, even the highest fluid production rates observed incur only small biosynthesis costs, representing less than 1 per cent of the resting metabolic rate. Our results show that fluid secretion in insect wet adhesive systems relies on simple physical principles, allowing for passive control of fluid volume within the contact zone. PMID:21208970

The forward undulatory locomotion of Ceanorhabditis elegans in viscoelastic fluids

NASA Astrophysics Data System (ADS)

Shen, Amy; Ulrich, Xialing

2013-11-01

Caenorhabditis elegans is a soil dwelling roundworm that has served as model organisms for studying a multitude of biological and engineering phenomena. We study the undulatory locomotion of nematode in viscoelastic fluids with zero-shear viscosity varying from 0.03-75 Pa .s and relaxation times ranging from 0-350 s. We observe that the averaged normalized wavelength of swimming worm is essentially the same as that in Newtonian fluids. The undulatory frequency f shows the same reduction rate with respect to zero-shear viscosity in viscoelastic fluids as that found in the Newtonian fluids, meaning that the undulatory frequency is mainly controlled by the fluid viscosity. However, the moving speed Vm of the worm shows more distinct dependence on the elasticity of the fluid and exhibits a 4% drop with each 10-fold increase of the Deborah number De, a dimensionless number characterizing the elasticity of a fluid. To estimate the swimming efficiency coefficient and the ratio K =CN /CL of resistive coefficients of the worm in various viscoelastic fluids, we show that whereas it would take the worm around 7 periods to move a body length in a Newtonian fluid, it would take 27 periods to move a body length in a highly viscoelastic fluid.

Amniotic fluid index predicts the relief of variable decelerations after amnioinfusion bolus.

PubMed

Spong, C Y; McKindsey, F; Ross, M G

1996-10-01

Our purpose was to determine whether intrapartum amniotic fluid index before amnioinfusion can be used to predict response to therapeutic amnioinfusion. Intrapartum patients (n = 85) with repetitive variable decelerations in fetal heart rate that necessitated amnioinfusion (10 ml/min for 60 minutes) underwent determination of amniotic fluid index before and after bolus amnioinfusion. The fetal heart tracing was scored (scorer blinded to amniotic fluid index values) for number and characteristics of variable decelerations before and 1 hour after initiation of amnioinfusion. The amnioinfusion was considered successful if it resulted in a decrease of > or = 50% in total number of variable decelerations or a decrease of > or = 50% in the rate of atypical or severe variable decelerations after administration of the bolus. Spontaneous vaginal births before completion of administration of the bolus (n = 18) were excluded from analysis. The probability of success of amnioinfusion in relation to amniotic fluid index was analyzed with the chi(2) test for progressive sequence. The mean amniotic fluid index before amnioinfusion was 6.2 +/- 3.3 cm. An amniotic fluid index of < or = 5 cm was present in 40% of patients (27/67), and an amniotic fluid index of < or = 8 cm was present in 72% of patients (48/67). The probability of success of amnioinfusion decreased with increasing amniotic fluid index before amnioinfusion (76% [16/21] when initial amniotic fluid index was 0 to 4 cm, 63% [17/27] when initial amniotic fluid index was 4 to 8 cm, 44% [7/16] when initial amniotic fluid index was 8 to 12 cm, and 33% [1/3] when initial amniotic fluid index was > 12 cm, p = 0.03). The incidence of nuchal cords or true umbilical cord knots increased in relation to amniotic fluid index before amnioinfusion. Amniotic fluid index before amnioinfusion can be used to predict the success of amnioinfusion for relief of variable decelerations in fetal heart rate. Failure of amnioinfusion at a high amniotic fluid index before amnioinfusion may be explained by the increased prevalence of nuchal cords or true knots in the umbilical cord.

Analysis of the association of fluid balance and short-term outcome in traumatic brain injury.

PubMed

Zhao, Zilong; Wang, Dong; Jia, Ying; Tian, Ye; Wang, Yi; Wei, Yingsheng; Zhang, Jianning; Jiang, Rongcai

2016-05-15

A balance of fluid intake and output (fluid balance) influences outcomes of critical illness, but the level of such influence remains poorly understood for traumatic brain injury (TBI) and was quantitatively examined in this study. We conducted a retrospective cohort study of 351 moderate and severe TBI patients to associate the degree of fluid balance with clinical outcomes of TBI. Fluid balance and intracranial pressure (ICP) were continuously recorded for 7days on patients admitted to neurocritical care unit (NCCU). The short-term outcome was dichotomized into improvement and deterioration groups based on changes in Glasgow Coma Scale (GCS) measured between admission and 30days after admission. Fluid balance was calculated as: Fluid intake (mL) - fluid outputs (mL)/day×5 and used to group patients in tertiles to study its effect on TBI outcome. Patients at the low (<637mL) and upper (>3673mL) tertiles of fluid balance were associated with poor outcomes. Those in the upper tertile also had a higher incidence of acute kidney injury (AKI) and refractory intracranial hypertension (RIH). There was a negative correlation between the cumulative fluid balance and the short-term outcome for patients in the low tertile and a positive correlation between the cumulative fluid balance and the short-term outcome in the upper fluid balance group. Levels of fluid balance were also associated with serum creatinine (Cr, r=0.451, P<0.0001) and days in NCCU (r=0.188, P=0.001). More patients in the upper tertile had ICP higher than 20mmHg (P=0.009). A fluid balance in the upper tertile is an independent predictor of poor 30-day clinical outcomes after the adjustment for confounding variables in a multivariable logistic regression model. We found that fluid balance in low and upper tertiles were associated with poor short-term outcomes and ICP variations. Fluid balance in the upper tertile may be an independent predictor for poor 30-day outcome, primarily due to high AKI and RIH. Copyright © 2016. Published by Elsevier B.V.

Conditions for fluid separations in microchannels, capillary-driven fluid separations, and laminated devices capable of separating fluids

DOEpatents

TeGrotenhuis, Ward E [Kennewick, WA; Stenkamp, Victoria S [Richland, WA

2005-04-05

Methods of separating fluids using capillary forces and/or improved conditions for are disclosed. The improved methods may include control of the ratio of gas and liquid Reynolds numbers relative to the Suratman number. Also disclosed are wick-containing, laminated devices that are capable of separating fluids.

Conditions for fluid separations in microchannels, capillary-driven fluid separations, and laminated devices capable of separating fluids

DOEpatents

TeGrotenhuis, Ward E [Kennewick, WA; Stenkamp, Victoria S [Richland, WA

2008-03-18

Methods of separating fluids using capillary forces and/or improved conditions for are disclosed. The improved methods may include control of the ratio of gas and liquid Reynolds numbers relative to the Suratman number. Also disclosed are wick-containing, laminated devices that are capable of separating fluids.

Reduced viscosity interpreted for fluid/gas mixtures

NASA Technical Reports Server (NTRS)

Lewis, D. H.

1981-01-01

Analysis predicts decrease in fluid viscosity by comparing pressure profile of fluid/gas mixture with that of power-law fluid. Fluid is taken to be viscous, non-Newtonian, and incompressible; the gas to be ideal; the flow to be inertia-free, isothermal, and one dimensional. Analysis assists in design of flow systems for petroleum, coal, polymers, and other materials.

Serious Fun: Using Toys to Demonstrate Fluid Mechanics Principles

ERIC Educational Resources Information Center

Saviz, Camilla M.; Shakerin, Said

2014-01-01

Many students have owned or seen fluids toys in which two immiscible fluids within a closed container can be tilted to generate waves. These types of inexpensive and readily available toys are fun to play with, but they are also useful for provoking student learning about fluid properties or complex fluid behavior, including drop formation and…

Raman imaging of fluid inclusions in garnet from UHPM rocks (Kokchetav massif, Northern Kazakhstan).

PubMed

Korsakov, Andrey V; Dieing, Thomas; Golovin, Aleksandr V; Toporski, Jan

2011-10-01

Confocal Raman imaging of fluid inclusions in garnet porphyroblasts from diamond-grade metamorphic calc-silicate rocks from the Kumdy-Kol microdiamond deposit (Kokchetav Massif, Northern Kazakhstan) reveals that these fluid inclusions consist of almost pure water with different step-daughter phases (e.g., calcite, mica and rare quartz). These fluid inclusions are characterized by negative crystal shape of the host-garnet and they exclusively occur within the core of garnet porphyroblasts. These observations are consistent with their primary origin, most likely at ultrahigh-pressure (UHP) metamorphic conditions. The euhedral newly formed garnet, different in color and composition, was found to be associated with these fluid inclusions. It is proposed that newly formed garnet and water fluid inclusions appear by reaction between the hydrous fluid and the garnet-host. These fluid inclusions provide an unequivocal record of almost pure H(2)O fluids, indicating water-saturated conditions within subducted continental crust during prograde stage and/or ultrahigh-P metamorphism. Copyright © 2011 Elsevier B.V. All rights reserved.

Electro-osmotic mobility of non-Newtonian fluids

PubMed Central

Zhao, Cunlu; Yang, Chun

2011-01-01

Electrokinetically driven microfluidic devices are usually used to analyze and process biofluids which can be classified as non-Newtonian fluids. Conventional electrokinetic theories resulting from Newtonian hydrodynamics then fail to describe the behaviors of these fluids. In this study, a theoretical analysis of electro-osmotic mobility of non-Newtonian fluids is reported. The general Cauchy momentum equation is simplified by incorporation of the Gouy–Chapman solution to the Poisson–Boltzmann equation and the Carreau fluid constitutive model. Then a nonlinear ordinary differential equation governing the electro-osmotic velocity of Carreau fluids is obtained and solved numerically. The effects of the Weissenberg number (Wi), the surface zeta potential (ψ¯s), the power-law exponent(n), and the transitional parameter (β) on electro-osmotic mobility are examined. It is shown that the results presented in this study for the electro-osmotic mobility of Carreau fluids are quite general so that the electro-osmotic mobility for the Newtonian fluids and the power-law fluids can be obtained as two limiting cases. PMID:21503161

Brief Report: Adherence to Fluid Recommendations in Children Receiving Treatment for Retentive Encopresis

PubMed Central

Felt, Barbara T.; Patton, Susana R.

2009-01-01

Objective Limited data are available regarding whether children being treated for retentive encopresis are adherent to recommendations to increase their daily fluid intake. The purpose of this study was to examine fluid adherence in children who received treatment for retentive encopresis. Methods A retrospective chart review was performed using diet diary data for 26 children (ages 3–12) who completed a group behavioral intervention for retentive encopresis. Results Mean daily intake of clear fluid increased significantly during treatment and children relied primarily on water and juice to make this dietary change. However, adherence rates to clear fluid goals were <50%. Conclusions Children's increased clear fluid intake did not equate to high fluid adherence. Children's high juice consumption is concerning as it could place them at risk for other negative health consequences. Future research should examine whether enhanced fluid education and use of behavior change strategies yield higher fluid adherence. PMID:19304779

Oxytocin-receptor-expressing neurons in the parabrachial nucleus regulate fluid intake.

PubMed

Ryan, Philip J; Ross, Silvano I; Campos, Carlos A; Derkach, Victor A; Palmiter, Richard D

2017-12-01

Brain regions that regulate fluid satiation are not well characterized, yet are essential for understanding fluid homeostasis. We found that oxytocin-receptor-expressing neurons in the parabrachial nucleus of mice (Oxtr PBN neurons) are key regulators of fluid satiation. Chemogenetic activation of Oxtr PBN neurons robustly suppressed noncaloric fluid intake, but did not decrease food intake after fasting or salt intake following salt depletion; inactivation increased saline intake after dehydration and hypertonic saline injection. Under physiological conditions, Oxtr PBN neurons were activated by fluid satiation and hypertonic saline injection. Oxtr PBN neurons were directly innervated by oxytocin neurons in the paraventricular hypothalamus (Oxt PVH  neurons), which mildly attenuated fluid intake. Activation of neurons in the nucleus of the solitary tract substantially suppressed fluid intake and activated Oxtr PBN neurons. Our results suggest that Oxtr PBN neurons act as a key node in the fluid satiation neurocircuitry, which acts to decrease water and/or saline intake to prevent or attenuate hypervolemia and hypernatremia.

The coupled dynamics of fluids and spacecraft in low gravity and low gravity fluid measurement

NASA Technical Reports Server (NTRS)

Hansman, R. John; Peterson, Lee D.; Crawley, Edward F.

1987-01-01

The very large mass fraction of liquids stored on broad current and future generation spacecraft has made critical the technologies of describing the fluid-spacecraft dynamics and measuring or gauging the fluid. Combined efforts in these areas are described, and preliminary results are presented. The coupled dynamics of fluids and spacecraft in low gravity study is characterizing the parametric behavior of fluid-spacecraft systems in which interaction between the fluid and spacecraft dynamics is encountered. Particular emphasis is given to the importance of nonlinear fluid free surface phenomena to the coupled dynamics. An experimental apparatus has been developed for demonstrating a coupled fluid-spacecraft system. In these experiments, slosh force signals are fed back to a model tank actuator through a tunable analog second order integration circuit. In this manner, the tank motion is coupled to the resulting slosh force. Results are being obtained in 1-g and in low-g (on the NASA KC-135) using dynamic systems nondimensionally identical except for the Bond numbers.

Viscoelasticity promotes collective swimming of sperm

NASA Astrophysics Data System (ADS)

Tung, Chih-Kuan; Harvey, Benedict B.; Fiore, Alyssa G.; Ardon, Florencia; Suarez, Susan S.; Wu, Mingming

From flocking birds to swarming insects, interactions of organisms large and small lead to the emergence of collective dynamics. Here, we report striking collective swimming of bovine sperm, with sperm orienting in the same direction within each cluster, enabled by the viscoelasticity of the fluid. A long-chain polyacrylamide solution was used as a model viscoelastic fluid such that its rheology can be fine-tuned to mimic that of bovine cervical mucus. In viscoelastic fluid, sperm formed dynamic clusters, and the cluster size increased with elasticity of the polyacrylamide solution. In contrast, sperm swam randomly and individually in Newtonian fluids of similar viscosity. Analysis of the fluid motion surrounding individual swimming sperm indicated that sperm-fluid interaction is facilitated by the elastic component of the fluid. We note that almost all biological fluids (e.g. mucus and blood) are viscoelastic in nature, this finding highlights the importance of fluid elasticity in biological function. We will discuss what the orientation fluctuation within a cluster reveals about the interaction strength. Supported by NIH Grant 1R01HD070038.

Rindler fluid with weak momentum relaxation

NASA Astrophysics Data System (ADS)

Khimphun, Sunly; Lee, Bum-Hoon; Park, Chanyong; Zhang, Yun-Long

2018-01-01

We realize the weak momentum relaxation in Rindler fluid, which lives on the time-like cutoff surface in an accelerating frame of flat spacetime. The translational invariance is broken by massless scalar fields with weak strength. Both of the Ward identity and the momentum relaxation rate of Rindler fluid are obtained, with higher order correction in terms of the strength of momentum relaxation. The Rindler fluid with momentum relaxation could also be approached through the near horizon limit of cutoff AdS fluid with momentum relaxation, which lives on a finite time-like cutoff surface in Anti-de Sitter(AdS) spacetime, and further could be connected with the holographic conformal fluid living on AdS boundary at infinity. Thus, in the holographic Wilson renormalization group flow of the fluid/gravity correspondence with momentum relaxation, the Rindler fluid can be considered as the Infrared Radiation(IR) fixed point, and the holographic conformal fluid plays the role of the ultraviolet(UV) fixed point.

Standard on microbiological management of fluids for hemodialysis and related therapies by the Japanese Society for Dialysis Therapy 2008.

PubMed

Kawanishi, Hideki; Akiba, Takashi; Masakane, Ikuto; Tomo, Tadashi; Mineshima, Michio; Kawasaki, Tadayuki; Hirakata, Hideki; Akizawa, Tadao

2009-04-01

The Committee of Scientific Academy of the Japanese Society for Dialysis Therapy (JSDT) proposes a new standard on microbiological management of fluids for hemodialysis and related therapies. This standard is within the scope of the International Organization for Standardization (ISO), which is currently under revision. This standard is to be applied to the central dialysis fluid delivery systems (CDDS), which are widely used in Japan. In this standard, microbiological qualities for dialysis water and dialysis fluids are clearly defined by endotoxin level and bacterial count. The qualities of dialysis fluids were classified into three levels: standard, ultrapure, and online prepared substitution fluid. In addition, the therapeutic application of each dialysis fluid is clarified. Since high-performance dialyzers are frequently used in Japan, the standard recommends that ultrapure dialysis fluid be used for all dialysis modalities at all dialysis facilities. It also recommends that the dialysis equipment safety management committee at each facility should validate the microbiological qualities of online prepared substitution fluid.

Episodic Tremor and Slip Explained by Fluid-Enhanced Microfracturing and Sealing

NASA Astrophysics Data System (ADS)

Bernaudin, M.; Gueydan, F.

2018-04-01

Episodic tremor and slow-slip events at the deep extension of plate boundary faults illuminate seismic to aseismic processes around the brittle-ductile transition. These events occur in volumes characterized by overpressurized fluids and by near failure shear stress conditions. We present a new modeling approach based on a ductile grain size-sensitive rheology with microfracturing and sealing, which provides a mechanical and field-based explanation of such phenomena. We also model pore fluid pressure variation as a function of changes in porosity/permeability and strain rate-dependent fluid pumping. The fluid-enhanced dynamic evolution of microstructures defines cycles of ductile strain localization and implies increase in pore fluid pressure. We propose that slow-slip events are ductile processes related to transient strain localization, while nonvolcanic tremor corresponds to fracturing of the whole rock at the peak of pore fluid pressure. Our model shows that the availability of fluids and the efficiency of fluid pumping control the occurrence and the P-T conditions of episodic tremor and slip.

A density functional theory for association of fluid molecules with a functionalized surface: fluid-wall single and double bonding.

PubMed

Haghmoradi, Amin; Wang, Le; Chapman, Walter G

2017-02-01

In this manuscript we extend Wertheim's two-density formalism beyond its first order to model a system of fluid molecules with a single association site close to a planar hard wall with association sites on its surface in a density functional theory framework. The association sites of the fluid molecules are small enough that they can form only one bond, while the wall association sites are large enough to bond with more than one fluid molecule. The effects of temperature and of bulk fluid and wall site densities on the fluid density profile, extent of association, and competition between single and double bonding of fluid segments at the wall sites versus distance from the wall are presented. The theory predictions are compared with new Monte Carlo simulation results and they are in good agreement. The theory captures the surface coverage over wide ranges of temperature and bulk density by introducing the effect of steric hindrance in fluid association at a wall site.

Fluid jet electric discharge source

DOEpatents

Bender, Howard A [Ripon, CA

2006-04-25

A fluid jet or filament source and a pair of coaxial high voltage electrodes, in combination, comprise an electrical discharge system to produce radiation and, in particular, EUV radiation. The fluid jet source is composed of at least two serially connected reservoirs, a first reservoir into which a fluid, that can be either a liquid or a gas, can be fed at some pressure higher than atmospheric and a second reservoir maintained at a lower pressure than the first. The fluid is allowed to expand through an aperture into a high vacuum region between a pair of coaxial electrodes. This second expansion produces a narrow well-directed fluid jet whose size is dependent on the size and configuration of the apertures and the pressure used in the reservoir. At some time during the flow of the fluid filament, a high voltage pulse is applied to the electrodes to excite the fluid to form a plasma which provides the desired radiation; the wavelength of the radiation being determined by the composition of the fluid.

Hyperacid volcano-hydrothermal fluids from Copahue volcano, Argentina: Analogs for "subduction zone fluids"?

NASA Astrophysics Data System (ADS)

Varekamp, J. C.

2007-12-01

Hyperacid concentrated Chlorine-Sulfate brines occur in many young arc volcanoes, with pH values <1, high concentrations of volcanogenic elements (S, Cl, F, As, B) and the main rock forming elements (Ca, Al, Mg, K, Na, P). Sulfur isotope data and Silica thermometry from such fluids sampled over a ten year period from the Copahue volcanic system (Argentina) suggest reservoir temperatures of 175-300 oC, whereas the surface fluids do not exceed local boiling temperatures. These fluids are generated at much lower P-T conditions than fluids associated with a dehydrating subducted sediment complex below arc volcanoes, but their fundamental chemical compositions may have similarities. Incompatible trace element, major element concentrations and Pb isotope compositions of the fluids were used to determine the most likely rock protoliths for these fluids. Mean rock- normalized trace element diagrams then indicate which elements are quantitatively extracted from the rocks and which are left behind or precipitated in secondary phases. Most LILE show flat rock-normalized patterns, indicating close to congruent dissolution, whereas Ta-Nb-Ti show strong depletions in the rock-normalized diagrams. These HFSE are either left behind in the altered rock protolith or were precipitated along the way up. The behavior of U and Th is almost identical, suggesting that in these low pH fluids with abundant ligands Th is just as easily transported as U, which is not the case in more dilute, neutral fluids. Most analyzed fluids have steeper LREE patterns than the rocks and have negative Eu anomalies similar to the rocks. Fluids that interacted with newly intruded magma e.g., during the 2000 eruption, have much less pronounced Eu anomalies, which was most likely caused by the preferential dissolution of plagioclase when newly intruded magma interacted with the acid fluids. The fluids show a strong positive correlation between Y and Cd (similar to MORB basalts, Yi et al., JGR, 2000), suggesting that Cd is mainly a rock-derived element that may not show chalcophilic behavior. The fluids are strongly enriched (relative to rock) in As, Zn and Pb, suggesting that these elements were carried with the volcanic gas phase into the system. In summary, if these fluids are broadly similar to fluids from dehydrating subducted sediments, they tend to transport preferently the LILE, LREE, U as well as Th, while the HFSE are left behind.

Fluid Inclusion Gas Analysis

DOE Data Explorer

Dilley, Lorie

2013-01-01

Fluid inclusion gas analysis for wells in various geothermal areas. Analyses used in developing fluid inclusion stratigraphy for wells and defining fluids across the geothermal fields. Each sample has mass spectrum counts for 180 chemical species.

Device and method for measuring fluid flow in a conduit having a gradual bend

DOEpatents

Ortiz, M.G.; Boucher, T.J.

1998-11-10

A system is described for measuring fluid flow in a conduit having a gradual bend or arc, and a straight section. The system includes pressure transducers, one or more disposed in the conduit on the outside of the arc, and one disposed in the conduit in a straight section thereof. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow. 1 fig.

Device and method for measuring multi-phase fluid flow in a conduit having an abrupt gradual bend

DOEpatents

Ortiz, M.G.

1998-02-10

A system is described for measuring fluid flow in a conduit having an abrupt bend. The system includes pressure transducers, one disposed in the conduit at the inside of the bend and one or more disposed in the conduit at the outside of the bend but spaced a distance therefrom. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow. 1 fig.

Hybrid microfluidic and nanofluidic system

DOEpatents

Bohn, Paul W [Champaign, IL; Sweedler, Jonathan V [Urbana, IL; Shannon, Mark A [Champaign, IL; Kuo, Tzu-chi [Savoy, IL

2007-05-22

A fluid circuit includes a membrane having a first side, a second side opposite the first side, and a pore extending from the first side to the second side. The circuit also includes a first channel containing fluid extending along the first side of the membrane and a second channel containing fluid extending along the second side of the membrane and crossing the first channel. The circuit also includes an electrical source in electrical communication with at least one of the first fluid and second fluid for selectively developing an electrical potential between fluid in the first channel and fluid in the second channel. This causes at least one component of fluid to pass through the pore in the membrane from one of the first channel and the second channel to the other of the first channel and the second channel.

Device and method for measuring fluid flow in a conduit having a gradual bend

DOEpatents

Ortiz, Marcos German; Boucher, Timothy J

1998-01-01

A system for measuring fluid flow in a conduit having a gradual bend or arc, and a straight section. The system includes pressure transducers, one or more disposed in the conduit on the outside of the arc, and one disposed in the conduit in a straight section thereof. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow.

Device and method for measuring multi-phase fluid flow in a conduit having an abrupt gradual bend

DOEpatents

Ortiz, Marcos German

1998-01-01

A system for measuring fluid flow in a conduit having an abrupt bend. The system includes pressure transducers, one disposed in the conduit at the inside of the bend and one or more disposed in the conduit at the outside of the bend but spaced a distance therefrom. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow.

Spinning fluids reactor

DOEpatents

Miller, Jan D; Hupka, Jan; Aranowski, Robert

2012-11-20

A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

Raman spectroscopic signature of vaginal fluid and its potential application in forensic body fluid identification.

PubMed

Sikirzhytskaya, Aliaksandra; Sikirzhytski, Vitali; Lednev, Igor K

2012-03-10

Traces of human body fluids, such as blood, saliva, sweat, semen and vaginal fluid, play an increasingly important role in forensic investigations. However, a nondestructive, easy and rapid identification of body fluid traces at the scene of a crime has not yet been developed. The obstacles have recently been addressed in our studies, which demonstrated the considerable potential of Raman spectroscopy. In this study, we continued to build a full library of body fluid spectroscopic signatures. The problems concerning vaginal fluid stain identification were addressed using Raman spectroscopy coupled with advanced statistical analysis. Calculated characteristic Raman and fluorescent spectral components were used to build a multidimensional spectroscopic signature of vaginal fluid, which demonstrated good specificity and was able to handle heterogeneous samples from different donors. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Hydraulic fracturing fluid migration in the subsurface: A review and expanded modeling results

NASA Astrophysics Data System (ADS)

Birdsell, Daniel T.; Rajaram, Harihar; Dempsey, David; Viswanathan, Hari S.

2015-09-01

Understanding the transport of hydraulic fracturing (HF) fluid that is injected into the deep subsurface for shale gas extraction is important to ensure that shallow drinking water aquifers are not contaminated. Topographically driven flow, overpressured shale reservoirs, permeable pathways such as faults or leaky wellbores, the increased formation pressure due to HF fluid injection, and the density contrast of the HF fluid to the surrounding brine can encourage upward HF fluid migration. In contrast, the very low shale permeability and capillary imbibition of water into partially saturated shale may sequester much of the HF fluid, and well production will remove HF fluid from the subsurface. We review the literature on important aspects of HF fluid migration. Single-phase flow and transport simulations are performed to quantify how much HF fluid is removed via the wellbore with flowback and produced water, how much reaches overlying aquifers, and how much is permanently sequestered by capillary imbibition, which is treated as a sink term based on a semianalytical, one-dimensional solution for two-phase flow. These simulations include all of the important aspects of HF fluid migration identified in the literature review and are performed in five stages to faithfully represent the typical operation of a hydraulically fractured well. No fracturing fluid reaches the aquifer without a permeable pathway. In the presence of a permeable pathway, 10 times more fracturing fluid reaches the aquifer if well production and capillary imbibition are not included in the model.

Perioperative fluid management: From physiology to improving clinical outcomes.

PubMed

Bennett, Victoria A; Cecconi, Maurizio

2017-08-01

Perioperative fluid management is a key component in the care of the surgical patient. It is an area that has seen significant changes and developments, however there remains a wide disparity in practice between clinicians. Historically, patients received large volumes of intravenous fluids perioperatively. The concept of goal directed therapy was then introduced, with the early studies showing significant improvements in morbidity and mortality. The current focus is on fluid therapy guided by an individual patient's physiology. A fluid challenge is commonly performed as part of an assessment of a patient's fluid responsiveness. There remains wide variation in how clinicians perform a fluid challenge and this review explores the evidence for how to administer an effective challenge that is both reliable and reproducible. The methods for monitoring cardiac output have evolved from the pulmonary artery catheter to a range of less invasive techniques. The different options that are available for perioperative use are considered. Fluid status can also be assessed by examining the microcirculation and the importance of recognising the possibility of a lack of coherence between the macro and microcirculation is discussed. Fluid therapy needs to be targeted to specific end points and individualised. Not all patients who respond to a fluid challenge will necessarily require additional fluid administration and care should be aimed at identifying those who do. This review aims to explain the underlying physiology and describe the evidence base and the changes that have been seen in the approach to perioperative fluid therapy.

The comparison of anti-oxidative kinetics in vitro of the fluid extract from maidenhair tree, motherwort and hawthorn.

PubMed

Bernatoniene, Jurga; Kucinskaite, Agne; Masteikova, Ruta; Kalveniene, Zenona; Kasparaviciene, Giedre; Savickas, Arunas

2009-01-01

The aim of the study was to perform a quantitative analysis of fluid extracts of maidenhair tree (Ginkgo biloba L.), motherwort (Leonurus cardiaca L.) and hawthorn (Crataegus monogyna Jacq.), to evaluate their antioxidant activity and to compare their ability to inactivate free radicals. The antioxidant activity was measured using the DPPH*and the ABTS*+ radical scavenging reaction systems. The study showed that the manifestation of the radical scavenging capacity in the DPPH* reaction system was in the following order: the fluid extract of hawthorn (70.37 +/- 0.80%) > the fluid extract of maidenhair tree (82.63 +/- 0.23%) > the fluid extract of motherwort (84.89 +/- 0.18%), while in the ABTS*+ reaction system, the manifestation of the radical scavenging capacity was in the following order: the fluid extract of hawthorn (87.09 +/- 0.55%) > the fluid extract of motherwort (88.28 +/- 1.06%) > the fluid extract of maidenhair tree (88.39 +/- 0.72%). The results showed that in the DPPH* reaction system, fluid extract of motherwort manifested higher antioxidant activity, compared to the fluid extracts of maidenhair tree and hawthorn. By contrast, in the ABTS*+ reaction system, higher antioxidant activity was found in the fluid extract of maidenhair tree, compared to the fluid extracts of motherwort and hawthorn. This would suggest that preparations manufactured from these herbal raw materials could be used as effective preventive means and valuable additional remedies in the treatment of diseases caused by oxidative stress.

In-vitro biocompatibility of alternative CAPD fluids; comparison of bicarbonate-buffered and glucose-polymer-based solutions.

PubMed

Jörres, A; Gahl, G M; Topley, N; Neubauer, A; Ludat, K; Müller, C; Passlick-Deetjen, J

1994-01-01

Evidence is accumulating that conventional dialysis fluids for CAPD are incompatible with peritoneal host defence. We therefore investigated the effect of alternative CAPD fluids on mononuclear leukocyte (PBMC) viability and cytokine production in vitro. Fluids tested were bicarbonate-buffered solutions containing 1.5% or 4.25% glucose, 7.5% glucose polymer dialysis fluid (GPDF), and conventional 1.5% glucose fluid (G1.5%). PBMC were stimulated (2 h, 37 degrees C) in the different test fluids with a clinical isolate of Staphylococcus epidermidis or Escherichia coli lipopolysaccharide. The cytokines TNF alpha and IL-6 in PBMC supernatants were measured by specific enzyme immunoassays. Induction of cytokine messenger RNA was evaluated by reverse transcription-polymerase chain reaction. Conventional G1.5% (pH 5.5) inhibited cytokine release from activated PBMC by > 95%, whereas cell responses in low-glucose bicarbonate fluid were not significantly reduced. In contrast, high-glucose bicarbonate fluid exerted > 80% inhibition despite its neutral pH. GPDF was inhibitory at its initial low pH, whereas cytokine release was restored following pH neutralization. Cytokine mRNA expression was suppressed by conventional G1.5% fluid and by high-glucose bicarbonate fluid. These data indicate that pH neutralization leads to a substantial improvement of dialysis fluid biocompatibility; however, hyperosmolality and/or high glucose content inhibit cell responsiveness even at normal pH. Replacement of glucose by glucose polymer might prove beneficial provided that the initial low pH is neutralized.

Tactic-specific differences in seminal fluid influence sperm performance

PubMed Central

Locatello, Lisa; Poli, Federica; Rasotto, Maria B.

2013-01-01

Seminal fluid often makes up a large part of an ejaculate, yet most empirical and theoretical studies on sperm competition have focused on how sperm characteristics (number and quality) affect fertilization success. However, seminal fluid influences own sperm performance and may potentially influence the outcome of sperm competition, by also affecting that of rivals. As a consequence males may be expected to allocate their investment in both sperm and seminal fluid in relation to the potential level of competition. Grass goby (Zosterisessor ophiocephalus) is an external fertilizer with guard-sneaker mating tactics, where sperm competition risk varies according to the tactic adopted. Here, we experimentally manipulated grass goby ejaculates by separately combining sperm and seminal fluid from territorial and sneaker males. While sperm of sneaker and territorial males did not differ in their performance when they interacted with their own seminal fluid only, sperm of sneakers increased their velocity and fertilization rate in the presence of territorial males' seminal fluid. By contrast, sneaker males' seminal fluid had a detrimental effect on the performance of territorial males' sperm. Sperm velocity was unaffected by the seminal fluid of males employing the same tactic, suggesting that seminal fluid's effect on rival-tactic sperm is not based on a self/non-self recognition mechanism. Our findings show that cross interactions of sperm and seminal fluid may influence the fertilization success of competing ejaculates with males investing in both sperm and seminal fluid in response to sperm competition risk. PMID:23363633

Tactic-specific differences in seminal fluid influence sperm performance.

PubMed

Locatello, Lisa; Poli, Federica; Rasotto, Maria B

2013-03-22

Seminal fluid often makes up a large part of an ejaculate, yet most empirical and theoretical studies on sperm competition have focused on how sperm characteristics (number and quality) affect fertilization success. However, seminal fluid influences own sperm performance and may potentially influence the outcome of sperm competition, by also affecting that of rivals. As a consequence males may be expected to allocate their investment in both sperm and seminal fluid in relation to the potential level of competition. Grass goby (Zosterisessor ophiocephalus) is an external fertilizer with guard-sneaker mating tactics, where sperm competition risk varies according to the tactic adopted. Here, we experimentally manipulated grass goby ejaculates by separately combining sperm and seminal fluid from territorial and sneaker males. While sperm of sneaker and territorial males did not differ in their performance when they interacted with their own seminal fluid only, sperm of sneakers increased their velocity and fertilization rate in the presence of territorial males' seminal fluid. By contrast, sneaker males' seminal fluid had a detrimental effect on the performance of territorial males' sperm. Sperm velocity was unaffected by the seminal fluid of males employing the same tactic, suggesting that seminal fluid's effect on rival-tactic sperm is not based on a self/non-self recognition mechanism. Our findings show that cross interactions of sperm and seminal fluid may influence the fertilization success of competing ejaculates with males investing in both sperm and seminal fluid in response to sperm competition risk.

Thermodynamic modeling of non-ideal mineral-fluid equilibria in the system Si-Al-Fe-Mg-Ca-Na-K-H-O-Cl at elevated temperatures and pressures: Implications for hydrothermal mass transfer in granitic rocks

NASA Astrophysics Data System (ADS)

Dolejš, David; Wagner, Thomas

2008-01-01

We present the results of thermodynamic modeling of fluid-rock interaction in the system Si-Al-Fe-Mg-Ca-Na-H-O-Cl using the GEM-Selektor Gibbs free energy minimization code. Combination of non-ideal mixing properties in solids with multicomponent aqueous fluids represents a substantial improvement and it provides increased accuracy over existing modeling strategies. Application to the 10-component system allows us to link fluid composition and speciation with whole-rock mineralogy, mass and volume changes. We have simulated granite-fluid interaction over a wide range of conditions (200-600 °C, 100 MPa, 0-5 m Cl and fluid/rock ratios of 10-2-104) in order to explore composition of magmatic fluids of variable salinity, temperature effects on fluid composition and speciation and to simulate several paths of alteration zoning. At low fluid/rock ratios (f/r) the fluid composition is buffered by the silicate-oxide assemblage and remains close to invariant. This behavior extends to a f/r of 0.1 which exceeds the amount of exsolved magmatic fluids controlled by water solubility in silicate melts. With increasing peraluminosity of the parental granite, the Na-, K- and Fe-bearing fluids become more acidic and the oxidation state increases as a consequence of hydrogen and ferrous iron transfer to the fluid. With decreasing temperature, saline fluids become more Ca- and Na-rich, change from weakly acidic to alkaline, and become significantly more oxidizing. Large variations in Ca/Fe and Ca/Mg ratios in the fluid are a potential geothermometer. The mineral assemblage changes from cordierite-biotite granites through two-mica granites to chlorite-, epidote- and zeolite-bearing rocks. We have carried out three rock-titration simulations: (1) reaction with the 2 m NaCl fluid leads to albitization, chloritization and desilication, reproducing essential features observed in episyenites, (2) infiltration of a high-temperature fluid into the granite at 400 °C leads to hydrolytic alteration commencing with alkali-feldspar breakdown and leading to potassic, phyllic and argillic assemblages; this is associated with reduction and iron metasomatism as observed in nature and (3) interaction with a multicomponent fluid at 600 °C produces sodic-calcic metasomatism. Na, Ca and Fe are the most mobile elements whereas immobility of Al is limited by f/r ∼ 400. All simulations predict a volume decrease by 3.4-5.4%, i.e., porosity formation at f/r < 30. At higher fluid/rock ratios simulation (2) produces a substantial volume increase (59%) due to mineral precipitation, whereas simulation (3) predicts a volume decrease by 49% at the advanced albitization-desilication stage. Volume changes closely correlate with mass changes of SiO2 and are related to silica solubility in fluids. The combined effects of oxygen fugacity, fluid acidity and pH for breakdown of aqueous metal complexes and precipitation of ore minerals were evaluated by means of reduced activity products. Sharp increases in saturation indexes for oxidative breakdown occur at each alteration zone whereas reductive breakdown or involvement of other chloride complexes favor precipitation at high fluid/rock ratios only. Calculations of multicomponent aqueous-solid equilibria at high temperatures and pressures are able to accurately predict rock mineralogy and fluid chemistry and are applicable to diverse reactive flow processes in the Earth's crust.

The geochemistry of fluids from an active shallow submarine hydrothermal system: Milos island, Hellenic Volcanic Arc

NASA Astrophysics Data System (ADS)

Valsami-Jones, E.; Baltatzis, E.; Bailey, E. H.; Boyce, A. J.; Alexander, J. L.; Magganas, A.; Anderson, L.; Waldron, S.; Ragnarsdottir, K. V.

2005-10-01

Geothermal activity in the Aegean island of Milos (Greece), associated with island-arc volcanism, is abundant both on-and off-shore. Hydrothermal fluids venting from several sites, mainly shallow submarine (up to 10 m), but also just above seawater level in one locality, were sampled over four summer field seasons. Some of the discharging fluids are associated with the formation of hydrothermal edifices. Overall, the main characteristics of the hydrothermal fluids are low pH and variable chlorinity. The lowest recorded pH was 1.7, and chlorinity ranged from 0.1 to 2.5 times that of seawater. The highest fluid temperatures recorded on site were 115 °C. Two main types of fluids were identified: low-chlorinity fluids containing low concentrations of alkalis (potassium, lithium, sodium) and calcium, and high concentrations of silica and sulphate; and high-chlorinity fluids containing high concentrations of alkalis and calcium, and lower concentrations of silica and sulphate. The type locality of the high-chlorinity fluids is shallow submarine in Palaeochori, near the east end of the south coast of the island, whereas the type locality of the low-chlorinity fluids is a cave to the west of Palaeochori. The two fluid types are therefore often referred to as "submarine" and "cave" fluids respectively. Both fluid types had low magnesium and high metal concentrations but were otherwise consistently different from each other. The low-chlorinity fluids had the highest cobalt, nickel, aluminium, iron and chromium (up to 1.6 μM, 3.6 μM, 1586 μM, 936 μM and 3.0 μM, respectively) and the high-chlorinity fluids had the highest zinc, cadmium, manganese and lead (up to 4.1 μM, 1.0 μM, 230 μM and 32 μM, respectively). Geochemical modelling suggests that metals in the former are likely to have been transported as sulphate species or free ions and in the latter as chloride species or free ions. Isotopic values for both water types range between δD -12 to 33‰ and δ 18O 1.2 to 4.6‰. The range of fluid compositions and isotopic contents indicates a complex history of evolution for the system. Both types of fluids appear to be derived from seawater and thus are likely to represent end members of a single fluid phase that underwent phase separation at depth.

[Present status and trend of heart fluid mechanics research based on medical image analysis].

PubMed

Gan, Jianhong; Yin, Lixue; Xie, Shenghua; Li, Wenhua; Lu, Jing; Luo, Anguo

2014-06-01

With introduction of current main methods for heart fluid mechanics researches, we studied the characteristics and weakness for three primary analysis methods based on magnetic resonance imaging, color Doppler ultrasound and grayscale ultrasound image, respectively. It is pointed out that particle image velocity (PIV), speckle tracking and block match have the same nature, and three algorithms all adopt block correlation. The further analysis shows that, with the development of information technology and sensor, the research for cardiac function and fluid mechanics will focus on energy transfer process of heart fluid, characteristics of Chamber wall related to blood fluid and Fluid-structure interaction in the future heart fluid mechanics fields.

Pump for delivering heated fluids

NASA Technical Reports Server (NTRS)

Sabelman, E. E. (Inventor)

1973-01-01

A thermomechanical pump particularly suited for use in pumping a warming fluid obtained from an RTG (Radioisotope Thermal Generator) through science and flight instrumentation aboard operative spacecraft is described. The invention is characterized by a pair of operatively related cylinders, each including a reciprocating piston head dividing the cylinder into a pressure chamber confining therein a vaporizable fluid, and a pumping chamber for propelling the warming fluid, and a fluid delivery circuit for alternately delivering the warming fluid from the RTG through the pressure chamber of one cylinder to the pumping chamber of the other cylinder, whereby the vaporizable fluid within the pair of pressure chambers alternately is vaporized and condensed for driving the associated pistons in pumping and intake strokes.

Third-space fluid shift in elderly patients undergoing gastrointestinal surgery: Part 1: Pathophysiological mechanisms.

PubMed

Redden, Maurine; Wotton, Karen

2002-06-01

Third-space fluid shift, the movement of body fluid to a non-functional space, is a frequently occurring and potentially fatal clinical phenomenon. Little published research exists however in medical or nursing journals concerning its incidence, significance and ramifications in elderly patients undergoing major gastrointestinal surgery. This initial article, part I, explores fluid movement between fluid compartments and uses these principles to discuss the pathophysiology of the two distinct phases of third-space fluid shift. Part II will examine the criteria nurses could use in the clinical assessment of patients in both first and second phases third-space fluid shift and discuss the clinical reliability of these criteria.

Energy Harvesting Systems and Methods of Assembling Same

NASA Technical Reports Server (NTRS)

Cepeda-Rizo, Juan (Inventor); Ganapathi, Gani B. (Inventor)

2013-01-01

A method of assembling an energy harvesting system is provided. The method includes coupling at least one energy storage device in flow communication with at least one apparatus that is configured to generate thermal energy and to transfer the thermal energy into at least one fluid stream. The energy storage device is configured to store the fluid stream. Moreover, the method includes coupling at least one fluid transfer device downstream from the energy storage device. The fluid transfer device receives the fluid stream from the energy storage device. A bladeless turbine is coupled in flow communication with the fluid transfer device, wherein the bladeless turbine receives the fluid stream to generate power.

Fiber optic fluid detector

DOEpatents

Angel, S.M.

1987-02-27

Particular gases or liquids are detected with a fiber optic element having a cladding or coating of a material which absorbs the fluid or fluids and which exhibits a change of an optical property, such as index of refraction, light transmissiveness or fluoresence emission, for example, in response to absorption of the fluid. The fluid is sensed by directing light into the fiber optic element and detecting changes in the light, such as exit angle changes for example, that result from the changed optical property of the coating material. The fluid detector may be used for such purposes as sensing toxic or explosive gases in the atmosphere, measuring ground water contamination or monitoring fluid flows in industrial processes, among other uses. 10 figs.

Stable isotope study of fluid inclusions in fluorite from Idaho: implications for continental climates during the Eocene

USGS Publications Warehouse

Seal, R.R.; Rye, R.O.

1993-01-01

Isotopic studies of fluid inclusions from meteoric water-dominated epithermal ore deposits offer a unique opportunity to study paleoclimates because the fluids can provide direct samples of ancient waters. Fluorite-hosted fluid inclusions from the Eocene (51-50 Ma) epithermal deposits of the Bayhorse mining district, have low salinities and low to moderate homogenization temperatures indicating meteoric origins for the fluids. Oxygen and hydrogen isotope data on inclusion fluids are almost identical to those of modern meteoric waters in the area. The equivalence of the isotope composition of the Eocene inclusion fluids and modern meteoric waters indicates that the Eocene climatic conditions were similar to those today. -from Authors

Accurate and rapid micromixer for integrated microfluidic devices

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

Van Dam, R. Michael; Liu, Kan; Shen, Kwang -Fu Clifton

2015-09-22

The invention may provide a microfluidic mixer having a droplet generator and a droplet mixer in selective fluid connection with the droplet generator. The droplet generator comprises first and second fluid chambers that are structured to be filled with respective first and second fluids that can each be held in isolation for a selectable period of time. The first and second fluid chambers are further structured to be reconfigured into a single combined chamber to allow the first and second fluids in the first and second fluid chambers to come into fluid contact with each other in the combined chambermore » for a selectable period of time prior to being brought into the droplet mixer.« less

Acute toxicity of two generic drilling fluids and six additives, alone and combined, to mysids (Mysidopsis bahia)

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

Parrish, P.R.; Macauley, J.M.; Montgomery, R.M.

1988-01-01

Toxicity tests were conducted with two laboratory-prepared generic drilling fluids (muds) and six commonly used drilling-fluid additives to determine their toxicity, alone and combined, to mysids (Mysidopsis bahia). In 25 tests, the acute toxicity of combinations of one, two, or three of the drilling-fluid additives mixed with either drilling fluid was less than the toxicity predicted from the empirical 96-h LC50s for drilling fluid additive(s) and/or drilling fluid alone; the observed 96-h LC50s of the mixtures were from 1.3 to 23.6 times the values predicted from the presumption of additive toxicity.

Spatiotemporal and geometric optimization of sensor arrays for detecting analytes fluids

DOEpatents

Lewis, Nathan S.; Freund, Michael S.; Briglin, Shawn M.; Tokumaru, Phil; Martin, Charles R.; Mitchell, David T.

2006-10-17

Sensor arrays and sensor array systems for detecting analytes in fluids. Sensors configured to generate a response upon introduction of a fluid containing one or more analytes can be located on one or more surfaces relative to one or more fluid channels in an array. Fluid channels can take the form of pores or holes in a substrate material. Fluid channels can be formed between one or more substrate plates. Sensor can be fabricated with substantially optimized sensor volumes to generate a response having a substantially maximized signal to noise ratio upon introduction of a fluid containing one or more target analytes. Methods of fabricating and using such sensor arrays and systems are also disclosed.

Spatiotemporal and geometric optimization of sensor arrays for detecting analytes in fluids

DOEpatents

Lewis, Nathan S [La Canada, CA; Freund, Michael S [Winnipeg, CA; Briglin, Shawn S [Chittenango, NY; Tokumaru, Phillip [Moorpark, CA; Martin, Charles R [Gainesville, FL; Mitchell, David [Newtown, PA

2009-09-29

Sensor arrays and sensor array systems for detecting analytes in fluids. Sensors configured to generate a response upon introduction of a fluid containing one or more analytes can be located on one or more surfaces relative to one or more fluid channels in an array. Fluid channels can take the form of pores or holes in a substrate material. Fluid channels can be formed between one or more substrate plates. Sensor can be fabricated with substantially optimized sensor volumes to generate a response having a substantially maximized signal to noise ratio upon introduction of a fluid containing one or more target analytes. Methods of fabricating and using such sensor arrays and systems are also disclosed.

Pressure balanced drag turbine mass flow meter

DOEpatents

Dacus, M.W.; Cole, J.H.

1980-04-23

The density of the fluid flowing through a tubular member may be measured by a device comprising a rotor assembly suspended within the tubular member, a fluid bearing medium for the rotor assembly shaft, independent fluid flow lines to each bearing chamber, and a scheme for detection of any difference between the upstream and downstream bearing fluid pressures. The rotor assembly reacts to fluid flow both by rotation and axial displacement; therefore concurrent measurements may be made of the velocity of blade rotation and also bearing pressure changes, where the pressure changes may be equated to the fluid momentum flux imparted to the rotor blades. From these parameters the flow velocity and density of the fluid may be deduced.

Pressure balanced drag turbine mass flow meter

DOEpatents

Dacus, Michael W.; Cole, Jack H.

1982-01-01

The density of the fluid flowing through a tubular member may be measured by a device comprising a rotor assembly suspended within the tubular member, a fluid bearing medium for the rotor assembly shaft, independent fluid flow lines to each bearing chamber, and a scheme for detection of any difference between the upstream and downstream bearing fluid pressures. The rotor assembly reacts to fluid flow both by rotation and axial displacement; therefore concurrent measurements may be made of the velocity of blade rotation and also bearing pressure changes, where the pressure changes may be equated to the fluid momentum flux imparted to the rotor blades. From these parameters the flow velocity and density of the fluid may be deduced.

Determining the Coefficient of Discharge for a Draining Container

ERIC Educational Resources Information Center

Hicks, Ashley; Slaton, William

2014-01-01

The flow of fluids through open containers is a topic studied frequently in introductory physics classes. A fluid mechanics class delves deeper into the topic of fluid flow through open containers with holes or barriers. The flow of a fluid jet out of a sharp-edged orifice rarely has the same area as the orifice due to a fluid flow phenomenon…

Supercritical Fluid Fractionation of JP-8

DTIC Science & Technology

1991-12-26

applications, such as coffee decaffeination , spice extraction, and lipids purification. The processing principles have also long been well known and ipracticed...PRINCIPLES OF SUPERCRITICAL FLUID EXTRACTION 8 A. Background on Supercritical Fluid Solubility 8 B. Supercritical Fluid Extraction Process ...Operation I0 1. Batch Extraction of Solid Materials 10 2. Counter-Current Continuous SCF Processing of Liquid 15 Products 3. Supercritical Fluid Extraction vs

Scrutinization of thermal radiation, viscous dissipation and Joule heating effects on Marangoni convective two-phase flow of Casson fluid with fluid-particle suspension

NASA Astrophysics Data System (ADS)

Mahanthesh, B.; Gireesha, B. J.

2018-03-01

The impact of Marangoni convection on dusty Casson fluid boundary layer flow with Joule heating and viscous dissipation aspects is addressed. The surface tension is assumed to vary linearly with temperature. Physical aspects of magnetohydrodynamics and thermal radiation are also accounted. The governing problem is modelled under boundary layer approximations for fluid phase and dust particle phase and then Runge-Kutta-Fehlberg method based numeric solutions are established. The momentum and heat transport mechanisms are focused on the result of distinct governing parameters. The Nusselt number is also calculated. It is established that the rate of heat transfer can be enhanced by suspending dust particles in the base fluid. The temperature field of fluid phase and temperature of dust phase are quite reverse for thermal dust parameter. The radiative heat, viscous dissipation and Joule heating aspects are constructive for thermal fields of fluid and dust phases. The velocity of dusty Casson fluid dominates the velocity of dusty fluid while this trend is opposite in the case of temperature. Moreover qualitative behaviour of fluid phase and dust phase temperature/velocity are similar.

Electrically controlled adjustable-resistance exercise equipment employing magnetorheological fluid

NASA Astrophysics Data System (ADS)

Lukianovich, Alex; Ashour, Osama N.; Thurston, Wilbert L.; Rogers, Craig A.; Chaudhry, Zaffir A.

1996-05-01

Magnetorheological (MR) fluids consist of stable suspensions of magnetic particles in a carrying fluid. The magnetorheological effect is one of the direct influences on the mechanical properties of a fluid. It represents a reversible increase, due to an external magnetic field, of the effective viscosity. Besides the variation of the rheological properties (viscosity, elasticity, and plasticity), the magnetic properties of the fluid (permeability and susceptibility), as well as the thermal and acoustic properties, are strongly influenced when an external magnetic field is applied. MR fluids have many appealing applications in the area of vibration control. The distinguishing feature of any MR fluid device is the absence of moving mechanical parts and the extreme simplicity of construction and technology. The most important element of any MR fluid device is an MR valve, which is functionally a controllable hydraulic resistance. As a demonstration of such devices, two commercially available pieces of exercise equipment, a cross stepper and a bench press, were modified to incorporate MR fluid and an external MR valve. As the magnetic field strength operating across the MR valve is adjusted, the viscosity of the flowing MR fluid changes and, accordingly, the needed force is adjusted.

The quantification of body fluid allostasis during exercise.

PubMed

Tam, Nicholas; Noakes, Timothy D

2013-12-01

The prescription of an optimal fluid intake during exercise has been a controversial subject in sports science for at least the past decade. Only recently have guidelines evolved from 'blanket' prescriptions to more individualised recommendations. Currently the American College of Sports Medicine advise that sufficient fluid should be ingested to ensure that body mass (BM) loss during exercise does not exceed >2 % of starting BM so that exercise-associated medical complications will be avoided. Historically, BM changes have been used as a surrogate for fluid loss during exercise. It would be helpful to accurately determine fluid shifts in the body in order to provide physiologically appropriate fluid intake advice. The measurement of total body water via D2O is the most accurate measure to detect changes in body fluid content; other methods, including bioelectrical impedance, are less accurate. Thus, the aim of this review is to convey the current understanding of body fluid allostasis during exercise when drinking according to the dictates of thirst (ad libitum). This review examines the basis for fluid intake prescription with the use of BM, the concepts of 'voluntary and involuntary dehydration' and the major routes by which the body gains and loses fluid during exercise.

Buoyancy driven mixing of miscible fluids by volumetric energy deposition of microwaves.

PubMed

Wachtor, Adam J; Mocko, Veronika; Williams, Darrick J; Goertz, Matthew P; Jebrail, Farzaneh F

2013-01-01

An experiment that seeks to investigate buoyancy driven mixing of miscible fluids by microwave volumetric energy deposition is presented. The experiment involves the use of a light, non-polar fluid that initially rests on top of a heavier fluid which is more polar. Microwaves preferentially heat the polar fluid, and its density decreases due to thermal expansion. As the microwave heating continues, the density of the lower fluid eventually becomes less than that of the upper, and buoyancy driven Rayleigh-Taylor mixing ensues. The choice of fluids is crucial to the success of the experiment, and a description is given of numerous fluid combinations considered and characterized. After careful consideration, the miscible pair of toluene/tetrahydrofuran (THF) was determined as having the best potential for successful volumetric energy deposition buoyancy driven mixing. Various single fluid calibration experiments were performed to facilitate the development of a heating theory. Thereafter, results from two-fluid mixing experiments are presented that demonstrate the capability of this novel Rayleigh-Taylor driven experiment. Particular interest is paid to the onset of buoyancy driven mixing and unusual aspects of the experiment in the context of typical Rayleigh-Taylor driven mixing.

Differential expression of genes of Xylella fastidiosa in xylem fluid of citrus and grapevine.

PubMed

Shi, Xiangyang; Bi, Jianlong; Morse, Joseph G; Toscano, Nick C; Cooksey, Donald A

2010-03-01

Xylella fastidiosa causes a serious Pierce's disease (PD) in grapevine. Xylella fastidiosa cells from a PD strain were grown in a pure xylem fluid of a susceptible grapevine cultivar vs. xylem fluid from citrus, which is not a host for this strain of X. fastidiosa. When grown in grapevine xylem fluid, cells of the PD strain formed clumps and biofilm formed to a greater extent than in citrus xylem fluid, although the PD strain did grow in xylem fluid of three citrus varieties. The differential expression of selected genes of a PD X. fastidiosa strain cultured in the two xylem fluids was analyzed using a DNA macroarray. Compared with citrus xylem fluid, grapevine xylem fluid stimulated the expression of X. fastidiosa genes involved in virulence regulation, such as gacA, algU, xrvA, and hsq, and also genes involved in the biogenesis of pili and twitching motility, such as fimT, pilI, pilU, and pilY1. Increased gene expression likely contributes to PD expression in grapevine, whereas citrus xylem fluid did not support or possibly suppressed the expression of these virulence genes.

Pediatric diabetic ketoacidosis, fluid therapy, and cerebral injury: the design of a factorial randomized controlled trial.

PubMed

Glaser, Nicole S; Ghetti, Simona; Casper, T Charles; Dean, J Michael; Kuppermann, Nathan

2013-09-01

Treatment protocols for pediatric diabetic ketoacidosis (DKA) vary considerably among centers in the USA and worldwide. The optimal protocol for intravenous (IV) fluid administration is an area of particular controversy, mainly in regard to possible associations between rates of IV fluid infusion and the development of cerebral edema (CE), the most common and the most feared complication of DKA in children. Theoretical concerns about associations between osmotic fluid shifts and CE have prompted recommendations for conservative fluid infusion during DKA. However, recent data suggest that cerebral hypoperfusion may play a role in cerebral injury associated with DKA. Currently, there are no existing data from prospective clinical trials to determine the optimal fluid treatment protocol for pediatric DKA. The Pediatric Emergency Care Applied Research Network FLUID (FLuid therapies Under Investigation in DKA) study is the first prospective randomized trial to evaluate fluid regimens for pediatric DKA. This 13-center nationwide factorial design study will evaluate the effects of rehydration rate and fluid sodium content on neurological status during DKA treatment, the frequency of clinically overt CE and long-term neurocognitive outcomes following DKA. © 2013 John Wiley & Sons A/S.

Economics of fluid therapy in critically ill patients.

PubMed

Lyu, Peter F; Murphy, David J

2014-08-01

Fluid therapy practices are an ongoing debate in critical care as evidence continues to emerge on the clinical effectiveness of different fluids and regimens. Although fluid therapy is a frequent and often costly treatment in the ICU, cost considerations have been largely absent from these studies. To facilitate a more structured approach to understanding fluid therapy costs and their role in clinical practice, we summarize currently available options and describe a framework for identifying and organizing relevant costs. Fluid therapy is a complex area of care that has been rarely studied from a cost-effectiveness perspective. We identify seven cost areas that capture fluid therapy-related costs during preutilization, point-of-utilization, and postutilization periods. These costs are driven by decisions on the type of fluid and administration strategy. Although estimates for some cost areas could be informed by medical literature, other cost areas remain unclear and require further investigation. Given the growing emphasis on the value of care, providers must recognize the important cost consequences of clinical decisions in fluid therapy. Future research into fluid therapy costs is needed and can be guided by this framework. Developing a complete cost picture is an initial and necessary step for improving values for patients, hospitals, and healthcare systems.

[Perioperative fluid therapy for surgical patients with chronic kidney disease].

PubMed

Iijima, Takehiko

2013-11-01

Chronic kidney disease (CKD) often accompanies cardiovascular complications, causing postoperative morbidity and even mortality. Since fluid and electrolyte homeostasis is deregulated in CKD patients, fluid therapy itself may cause postoperative morbidity. Recent studies have shown that forced diuresis through fluid overload offers no renoprotective effect and instead has harmful consequences. Fluid overload should be avoided, and the volume load should be used as the rationale for controlling hemodynamics. The emerging concept of a "zero-fluid balance policy" may be beneficial even for CKD patients. Hydroxyethylstarch might not be preferentially used for CKD patients. Hydroxyethylstarch is not contraindicated for CKD patients except in cases with long-term accumulation caused by increased vascular permeability, such as cases with sepsis, as long as an efficient volume expansion is beneficial to the patient. The regulation of renal function through the endocrine system (i.e., renin-angiotensin-aldosterone and vasopressin) is a key target for protecting the kidney in CKD. The recent development of a receptor blocker targeting these endocrine systems may be beneficial for correcting the fluid balance caused by excess intraoperative fluid therapy. The main issue for fluid therapy in surgical CKD patients may not be the quantity of fluid, but rational intervention affecting the endocrine system.

Portable device and method for determining permeability characteristics of earth formations

DOEpatents

Shuck, Lowell Z.

1977-01-01

The invention is directed to a device which is used for determining permeability characteristics of earth formations at the surface thereof. The determination of the maximum permeability direction and the magnitude of permeability are achieved by employing a device comprising a housing having a central fluid-injection port surrounded by a plurality of spaced-apart fluid flow and pressure monitoring ports radially extending from the central injection port. With the housing resting on the earth formation in a relatively fluid-tight manner as provided by an elastomeric pad disposed therebetween, fluid is injected through the central port into the earth formation and into registry with the fluid-monitoring ports disposed about the injection port. The fluid-monitoring ports are selectively opened and the flow of the fluid through the various fluid ports is measured so as to provide a measurement of flow rates and pressure distribution about the center hole which is indicative on the earth formation permeability direction and magnitude. For example, the azimuthal direction of the fluid-monitoring ports in the direction through which the greatest amount of injected fluid flows as determined by the lowest pressure distribution corresponds to the direction of maximum permeability in the earth formation.

Numerical analysis and experiment research on fluid orbital performance of vane type propellant management device

NASA Astrophysics Data System (ADS)

Hu, Q.; Li, Y.; Pan, H. L.; Liu, J. T.; Zhuang, B. T.

2015-01-01

Vane type propellant management device (PMD) is one of the key components of the vane-type surface tension tank (STT), and its fluid orbital performance directly determines the STT's success or failure. In present paper, numerical analysis and microgravity experiment study on fluid orbital performance of a vane type PMD were carried out. By using two-phase flow model of volume of fluid (VOF), fluid flow characteristics in the tank with the vane type PMD were numerically calculated, and the rules of fluid transfer and distribution were gotten. A abbreviate model test system of the vane type PMD is established and microgravity drop tower tests were performed, then fluid management and transmission rules of the vane type PMD were obtained under microgravity environment. The analysis and tests results show that the vane type PMD has good and initiative fluid orbital management ability and meets the demands of fluid orbital extrusion in the vane type STT. The results offer valuable guidance for the design and optimization of the new generation of vane type PMD, and also provide a new approach for fluid management and control in space environment.

Laser microprobe analyses of noble gas isotopes and halogens in fluid inclusions: Analyses of microstandards and synthetic inclusions in quartz

USGS Publications Warehouse

Böhlke, J.K.; Irwin, J.J.

1992-01-01

Ar, Kr, Xe, Cl, Br, I, and K abundances and isotopic compositions have been measured in microscopic fluid inclusions in minerals by noble gas mass spectrometry following neutron irradiation and laser extraction. The laser microprobe noble gas mass spectrometric (LMNGMS) technique was quantified by use of microstandards, including air-filled capillary tubes, synthetic basalt glass grains, standard hornblende grains, and synthetic fluid inclusions in quartz. Common natural concentrations of halogens (Cl, Br, and I) and noble gases (Ar and Kr) in trapped groundwaters and hydrothermal fluids can be analyzed simultaneously by LMNGMS in as little as 10−11 L of inclusion fluid, with accuracy and precision to within 5–10% for element and isotope ratios. Multicomponent element and isotope correlations indicate contaminants or persistent reservoirs of excess Xe and/or unfractionated air in some synthetic and natural fluid inclusion samples. LMNGMS analyses of natural fluid inclusions using the methods and calibrations reported here may be used to obtain unique information on sources of fluids, sources of fluid salinity, mixing, boiling (or unmixing), and water-rock interactions in ancient fluid flow systems.

The Fluids and Combustion Facility

NASA Technical Reports Server (NTRS)

Kundu, Sampa

2004-01-01

Microgravity is an environment with very weak gravitational effects. The Fluids and Combustion Facility (FCF) on the International Space Station (ISS) will support the study of fluid physics and combustion science in a long-duration microgravity environment. The Fluid Combustion Facility's design will permit both independent and remote control operations from the Telescience Support Center. The crew of the International Space Station will continue to insert and remove the experiment module, store and reload removable data storage and media data tapes, and reconfigure diagnostics on either side of the optics benches. Upon completion of the Fluids Combustion Facility, about ten experiments will be conducted within a ten-year period. Several different areas of fluid physics will be studied in the Fluids Combustion Facility. These areas include complex fluids, interfacial phenomena, dynamics and instabilities, and multiphase flows and phase change. Recently, emphasis has been placed in areas that relate directly to NASA missions including life support, power, propulsion, and thermal control systems. By 2006 or 2007, a Fluids Integrated Rack (FIR) and a Combustion Integrated Rack (CIR) will be installed inside the International Space Station. The Fluids Integrated Rack will contain all the hardware and software necessary to perform experiments in fluid physics. A wide range of experiments that meet the requirements of the international space station, including research from other specialties, will be considered. Experiments will be contained in subsystems such as the international standard payload rack, the active rack isolation system, the optics bench, environmental subsystem, electrical power control unit, the gas interface subsystem, and the command and data management subsystem. In conclusion, the Fluids and Combustion Facility will allow researchers to study fluid physics and combustion science in a long-duration microgravity environment. Additional information is included in the original extended abstract.

Extended Detection of Amphetamine and Methamphetamine in Oral Fluid.

PubMed

Andås, Hilde T; Enger, Asle; Øiestad, Åse Marit L; Vindenes, Vigdis; Christophersen, Asbjørg S; Huestis, Marilyn A; Øiestad, Elisabeth L

2016-02-01

Amphetamine and methamphetamine are popular drugs of abuse worldwide and are important components of drug monitoring programs. Windows of detection for amphetamine and methamphetamine in oral fluid after high doses have not been investigated. Repeated high-dose ingestions are likely to cause positive samples for extended periods. Common routes of administration of amphetamine/methamphetamine in Norway are oral intake or injection. The aim of this study was to investigate windows of detection for amphetamine and methamphetamine in oral fluid from drug addicts under sustained abstinence during detoxification. Twenty-five patients admitted to a closed detoxification unit were included in this study. Oral fluid samples were collected daily in the morning and evening, and urine every morning for 10 days. A blood sample was drawn during the first 5 days after admission if the patient consented. Oral fluid results were compared with urine results to determine whether a new ingestion occurred. Oral fluid was collected with the Intercept oral fluid collection device. In-house cutoff concentrations for amphetamine and methamphetamine were 6.8 and 7.5 mcg/L, respectively, in oral fluid, and 135 and 149 mcg/L, respectively, in urine. Amphetamines were detected in 11 oral fluid, 5 urine, and 2 blood specimens from 25 patients. Patients self-reported amphetamines intake of up to 0.5-2 g daily. Windows of detection for amphetamine and methamphetamine in oral fluid were up to 8 days, longer than in urine at the applied cutoff values. These data confirm that oral fluid is a viable alternative to urine for monitoring amphetamine abuse, and that these substances might be detected in oral fluid for at least 1 week after ingestion of high doses. Such long detection times were, as far as we are aware, never reported previously for oral fluid amphetamines.

Liberal Versus Restrictive Intravenous Fluid Therapy for Early Septic Shock: Rationale for a Randomized Trial.

PubMed

Self, Wesley H; Semler, Matthew W; Bellomo, Rinaldo; Brown, Samuel M; deBoisblanc, Bennett P; Exline, Matthew C; Ginde, Adit A; Grissom, Colin K; Janz, David R; Jones, Alan E; Liu, Kathleen D; Macdonald, Stephen P J; Miller, Chadwick D; Park, Pauline K; Reineck, Lora A; Rice, Todd W; Steingrub, Jay S; Talmor, Daniel; Yealy, Donald M; Douglas, Ivor S; Shapiro, Nathan I

2018-05-09

Prompt intravenous fluid therapy is a fundamental treatment for patients with septic shock. However, the optimal approach for administering intravenous fluid in septic shock resuscitation is unknown. Two competing strategies are emerging: a liberal fluids approach, consisting of a larger volume of initial fluid (50 to 75 mL/kg [4 to 6 L in an 80-kg adult] during the first 6 hours) and later use of vasopressors, versus a restrictive fluids approach, consisting of a smaller volume of initial fluid (≤30 mL/kg [≤2 to 3 L]), with earlier reliance on vasopressor infusions to maintain blood pressure and perfusion. Early fluid therapy may enhance or maintain tissue perfusion by increasing venous return and cardiac output. However, fluid administration may also have deleterious effects by causing edema within vital organs, leading to organ dysfunction and impairment of oxygen delivery. Conversely, a restrictive fluids approach primarily relies on vasopressors to reverse hypotension and maintain perfusion while limiting the administration of fluid. Both strategies have some evidence to support their use but lack robust data to confirm the benefit of one strategy over the other, creating clinical and scientific equipoise. As part of the National Heart, Lung, and Blood Institute Prevention and Early Treatment of Acute Lung Injury Network, we designed a randomized clinical trial to compare the liberal and restrictive fluids strategies, the Crystalloid Liberal or Vasopressor Early Resuscitation in Sepsis trial. The purpose of this article is to review the current literature on approaches to early fluid resuscitation in adults with septic shock and outline the rationale for the upcoming trial. Copyright © 2018 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

Intake of water and different beverages in adults across 13 countries.

PubMed

Guelinckx, I; Ferreira-Pêgo, C; Moreno, L A; Kavouras, S A; Gandy, J; Martinez, H; Bardosono, S; Abdollahi, M; Nasseri, E; Jarosz, A; Ma, G; Carmuega, E; Babio, N; Salas-Salvadó, J

2015-06-01

To describe the intake of water and all other fluids and to evaluate the proportion of adults exceeding the World Health Organisation (WHO) recommendations on energy intake from free sugar, solely from fluids. A total of 16,276 adults (46 % men, mean age 39.8 years) were recruited in 13 countries from 3 continents. A 24-h fluid-specific record over 7 days was used for fluid assessment. In Spain, France, Turkey, Iran, Indonesia and China, fluid intake was characterised by a high contribution of water (47-78 %) to total fluid intake (TFI), with a mean water intake between 0.76 and 1.78 L/day, and a mean energy intake from fluids from 182 to 428 kcal/day. Between 11 and 49 % of adults exceeded the free sugar WHO recommendations, considering solely fluids. In Germany, UK, Poland and Japan, the largest contributors to TFI were hot beverages (28-50 %) and water (18-32 %). Mean energy intake from fluids ranged from 415 to 817 kcal/day, and 48-62 % of adults exceeded free sugar WHO recommendations. In Mexico, Brazil and Argentina, the contribution of juices and regular sugar beverages (28-41 %) was as important as the water contribution to TFI (17-39 %). Mean energy intake from fluids ranged 565-694 kcal/day, and 60-66 % of the adults exceeded the free sugar WHO recommendation. The highest volumes recorded in most of the countries were for water, mean energy intake from fluids was up to 694 kcal/day, and 66 % of adults exceeded the free sugar WHO recommendation solely by fluids. Actions to create an environment in favour of water consumption and reduce sugar intake from fluids therefore are warranted.