Flows of Linear Polymer Solutions and Other Suspensions of Rod-like Particles: Anisotropic Micropolar-Fluid Theory Approach

We formulate equations governing flows of suspensions of rod-like particles. Such suspensions include linear polymer solutions, FD-virus, and worm-like micelles. To take into account the particles that form and their rotation, we treat the suspension as a Cosserat continuum and apply the theory of micropolar fluids. Anisotropy of suspensions is determined through the inclusion of the microinertia tensor in the rheological constitutive equations. We check that the model is consistent with the basic principles of thermodynamics. In addition to anisotropy, the theory also captures gradient banding instability, coexistence of isotropic and nematic phases, sustained temporal oscillations of macroscopic viscosity, shear thinning and hysteresis. For the flow between two planes, we also establish that the total flow rate depends not only on the pressure gradient, but on the history of its variation as well.

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On the Publishing Infrastructure of the University and its Construction Principles

Bibliotekovedenie [Library and Information Science (Russia)] ◽

10.25281/0869-608x-2010-0-1-121-126 ◽

2010 ◽

pp. 121-126

Author(s):

Tatyana F. Berestova ◽

Vera R. Abramovskih

Keyword(s):

Research Library ◽

Basic Principles ◽

History Of ◽

Publishing Infrastructure ◽

Distribution Sector ◽

The University

The basic principles of publishing activities in universities and their interrelation, all stages of redaction, the problems each of them, and ways to solve them. The activities of the distribution sector of publishing in the structure of the Research Library of Chelyabinsk State Academy of Culture and Arts and the history of its creation are described.

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Effects of water salinity on the foam dynamics for EOR application

Journal of Petroleum Exploration and Production Technology ◽

10.1007/s13202-021-01246-7 ◽

2021 ◽

Author(s):

Svetlana Rudyk ◽

Sami Al-Khamisi ◽

Yahya Al-Wahaibi

Keyword(s):

Flow Rate ◽

Liquid Flow ◽

Apparent Viscosity ◽

Liquid Flow Rate ◽

Salinity Range ◽

Porous System ◽

Foam Formation ◽

Total Flow ◽

Total Flow Rate ◽

Foam Flow

AbstractFactors limiting foam injection for EOR application are exceptionally low rock permeability and exceedingly high salinity of the formation water. In this regard, foam formation using internal olefin sulfonate is investigated over a wide salinity range (1, 5, 8, 10, and 12% NaCl) through 10 mD limestone. The relationships between pressure drop (dP), apparent viscosity, liquid flow rate, total flow rate, salinity, foam texture, and length of foam drops at the outlet used as an indicator of viscosity are studied. Foaming is observed up to 12% NaCl, compared to a maximum of 8% NaCl in similar core-flooding experiments with 50 mD limestone and 255 mD sandstone. Thus, the salinity limit of foam formation has increased significantly due to the low permeability, which can be explained by the fact that the narrow porous system acts like a membrane with smaller holes. Compared to the increasing dP reported for highly permeable rocks, dP linearly decreases in almost the entire range of gas fraction (fg) at 1–10% NaCl. As fg increases, dP at higher total flow rate is higher at all salinities, but the magnitude of dP controls the dependence of apparent viscosity on total flow rate. Low dP is measured at 1% and 10% NaCl, and high dP is measured at 5, 8, and 12% NaCl. In the case of low dP, the apparent viscosity is higher at higher total flow rate with increasing gas fraction, but similar at two total flow rates with increasing liquid flow rate. In the case of high dP, the apparent viscosity is higher at lower total flow rate, both with an increase in the gas fraction and with an increase in the liquid flow rate. A linear correlation is found between dP or apparent viscosity and liquid flow rate, which defines it as a governing factor of foam flow and can be considered when modeling foam flow.

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Rotational Particle Separation in Solutions: Micropolar Fluid Theory Approach

Polymers ◽

10.3390/polym13071072 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1072

Author(s):

Vladimir Shelukhin

Keyword(s):

Mathematical Model ◽

Rotational Diffusion ◽

Particle Separation ◽

Theory Approach ◽

Steady Flows ◽

Concentric Cylinder ◽

Polar Fluid ◽

Fluid Theory ◽

Couette Cell ◽

Granular Fluid

We develop a new mathematical model for rotational sedimentation of particles for steady flows of a viscoplastic granular fluid in a concentric-cylinder Couette geometry when rotation of the Couette cell inner cylinder is prescribed. We treat the suspension as a micro-polar fluid. The model is validated by comparison with known data of measurement. Within the proposed theory, we prove that sedimentation occurs due to particles’ rotation and rotational diffusion.

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A Notion of μηδέv in the Philosophy of Aristotle

The Paideia Archive: Twentieth World Congress of Philosophy ◽

10.5840/wcp20-paideia1998374 ◽

1998 ◽

pp. 286-289

Author(s):

Jolanta Swiderek

Keyword(s):

Basic Principles ◽

Human Thought ◽

History Of

This article shows that Aristotle created the first notion of a zero in the history of human thought. Since this notion stood in evident contradiction to the basic principles of his metaphysics and logic, he rejected it.

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Pediatric burn resuscitation: past, present, and future

Burns & Trauma ◽

10.1186/s41038-017-0091-y ◽

2017 ◽

Vol 5 ◽

Cited By ~ 15

Author(s):

Kathleen S. Romanowski ◽

Tina L. Palmieri

Keyword(s):

Fluid Resuscitation ◽

Burn Injury ◽

Total Body Surface Area ◽

Burn Shock ◽

Basic Principles ◽

Future Directions ◽

Number Of Children ◽

History Of ◽

Adults And Children ◽

Total Body

Abstract Burn injury is a leading cause of unintentional death and injury in children, with the majority being minor (less than 10%). However, a significant number of children sustain burns greater than 15% total body surface area (TBSA), leading to the initiation of the systemic inflammatory response syndrome. These patients require IV fluid resuscitation to prevent burn shock and death. Prompt resuscitation is critical in pediatric patients due to their small circulating blood volumes. Delays in resuscitation can result in increased complications and increased mortality. The basic principles of resuscitation are the same in adults and children, with several key differences. The unique physiologic needs of children must be adequately addressed during resuscitation to optimize outcomes. In this review, we will discuss the history of fluid resuscitation, current resuscitation practices, and future directions of resuscitation for the pediatric burn population.

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EXTRACTION OF MINUTE GAS BUBBLES FROM LIQUIDS FLOWING IN A SIMULATED CARDIOPULMONARY BYPASS SYSTEM BY A VENTURI-ASPIRATOR UNIT

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519402000514 ◽

2002 ◽

Vol 02 (03n04) ◽

pp. 297-312

Author(s):

WEN-JEI YANG ◽

AMR EID ◽

R. ECHIGO

Keyword(s):

Cardiopulmonary Bypass ◽

Flow Rate ◽

Whole Blood ◽

Pressure Difference ◽

Gas Bubbles ◽

Blood Oxygenation ◽

Straight Tube ◽

Suction Pressure ◽

Total Flow ◽

Total Flow Rate

An experimental study is performed to extract minute gas bubbles from liquids flowing in a simulated cardiopulmonary bypass system using a Venturi-aspirator unit. In other words, oxygen bubbles in oxygenated blood are simulated by air bubbles in water with AP30 (about same viscosity as whole blood). This study is intended to determine the feasibility of using a Venturi aspirator unit to extract minute gas bubbles from a simulated cardiopulmonary bypass system. Testing of the Venturi-type bubble extraction is carried out using three different test sections. Two Venturis are used, and a straight tube configuration is used as a control. The two Venturis are similar, with the exception that one has a longer inlet cone which causes the entering liquid to accelerate at a slower rate. Results are obtained for effectiveness of the aspirator unit as functions of total flow rate, extraction suction, suction pressure difference, and hydraulic head. It is concluded from the study that:(i) The effectiveness of the Venturis is typically between 90 and 100 percent. It increases with an increase in suction or suction pressure difference but decreases with an increase in total flow rate.(ii) The Venturi is most suitable for extraction of minute gas bubbles, especially for use with AP30 (whole blood), which yields substantially higher effectiveness than water.(iii) It is anticipated that a Venturi-aspirator unit can be superior to other bubble separation device as the cardiopulmonary bypass system for applications in extra corporeal blood oxygenation.

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Feasibility Study on Downhole Gas–Liquid Separator Design and Experiment Based on the Phase Isolation Method

Applied Sciences ◽

10.3390/app112110496 ◽

2021 ◽

Vol 11 (21) ◽

pp. 10496

Author(s):

Yuntong Yang ◽

Zhaoyu Jiang ◽

Lianfu Han ◽

Wancun Liu ◽

Xingbin Liu ◽

...

Keyword(s):

Numerical Simulation ◽

Gas Phase ◽

Separation Efficiency ◽

Dynamic Test ◽

Phase Flow ◽

Total Flow ◽

Total Flow Rate ◽

Two Phase ◽

Oil Gas ◽

Liquid Separator

As oil exploitation enters its middle and late stages, formation pressure drops, and crude oil degases. In production profile logging, the presence of the gas phase will affect the initial oil–water two-phase flowmeter’s flow measurement results. In order to eliminate gas-phase interference and reduce measurement costs, we designed a downhole gas–liquid separator (DGLS) suitable for low flow, high water holdup, and high gas holdup. We based it on the phase isolation method. Using a combination of numerical simulation and fluid dynamic measurement experiments, we studied DGLS separation efficiency separately in the two cases of gas–water two-phase flow and oil–gas–water three-phase flow. Comparative analysis of the numerical simulation calculation and dynamic test results showed that: the VOF model constructed based on k−ε the equation is nearly identical to the dynamic test, and can be used to analyze DGLS separation efficiency; the numerical simulation results of the gas–water two-phase flow show that when the total flow rate is below 20 m3/d, the separation efficiency surpasses 90%. The oil–gas–water three-phase’s numerical simulation results show that the oil phase influences separation efficiency. When the total flow rate is 20 m3/d–50 m3/d and gas holdup is low, the DGLS’s separation efficiency can exceed 90%. Our experimental study on fluid dynamics measurement shows that the DGLS’s applicable range is when the gas mass is 0 m3/d~15 m3/d, and the water holdup range is 50%~100%. The research presented in this article can provide a theoretical basis for the development and design of DGLSs.

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Relationship between international law and religion

Globus ◽

10.31618/2658-5197-2020-52-6-2 ◽

2020 ◽

Author(s):

H. Mammadov ◽

◽

Zh. Mammadova ◽

Keyword(s):

International Relations ◽

International Law ◽

Detailed Analysis ◽

Mutual Influence ◽

First Century ◽

Basic Principles ◽

History Of ◽

Twenty First Century ◽

History Of International Law

This article is devoted to the problems of mutual influence and interaction of international law and religion. In particular, it examines the development of international law and the sources of religion. In addition, which areas of international law are most developed under the influence of religious provisions. The history of international law knows various theories under which international law has improved. The article provides a detailed analysis of these theories and views, noting the institutions of international law that arose directly under the influence of religion. For example, it is noted that under the influence of Relia, the UN Charter codifies the basic principles of international law, etc. In addition, it shows the challenges of religion to international law and relations in the era of globalization in the twenty-first century, which led even to the undermining of modern international relations and traditional religious concepts caused by the " return of religion” in international relations; secondly, it presents and discusses the research path of religion and international relations. Finally, a brief analysis of the 2 impact of the global revival of religion and the ”return of religion" in international law and international relations has been carried out

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Organophosphorus Poisoning

Journal of Nepal Medical Association ◽

10.31729/jnma.170 ◽

2008 ◽

Vol 47 (172) ◽

Cited By ~ 24

Author(s):

Buddhi Prasad Paudyal

Keyword(s):

Signs And Symptoms ◽

Clinical Problem ◽

Acute Poisoning ◽

The Body ◽

Organophosphorus Insecticides ◽

Basic Principles ◽

Initial Management ◽

Organophosphorus Poisoning ◽

Life Threatening ◽

History Of

Acute poisoning by organophosphorus (OP) compounds is a major global clinical problem, withthousands of deaths occurring every year. Most of these pesticide poisoning and subsequentdeaths occur in developing countries following a deliberate self ingestion of the poison. Metacid(Methyl parathion) and Nuvan (Dichlorovos) are commonly ingested OP pesticides; Dimethoate,Profenofos, and Chlorpyrifos are other less frequently ingested compounds in Nepal. The toxicityof these OP pesticides is due to the irreversible inhibition of acetylcholinesterase (AChE) enzymeleading to accumulation of acetylcholine and subsequent over-activation of cholinergic receptorsin various parts of the body. Acutely, these patients present with cholinergic crisis; intermediatesyndrome and delayed polyneuropathy are other sequel of this form of poisoning. The diagnosisdepends on the history of exposure to these pesticides, characteristic manifestations of toxicityand improvements of the signs and symptoms after administration of atropine. The supportivetreatment of OP poisoning includes the same basic principles of management of any acutelypoisoned patient i.e., rapid initial management of airways, breathing, and circulation. Gastriclavage and activated charcoal are routinely used decontamination procedures, but their valuehas not been conclusively proven in this poisoning. Atropine is the mainstay of therapy, andcan reverse the life threatening features of this acute poisoning. However, there are no clearcut guidelines on the dose and duration of atropine therapy in OP poisoning. Cholinesterasereactivators, by regenerating AChE, can reverse both the nicotinic and muscarinic effects;however, this benefit has not been translated well in clinical trials. All these facts highlight thatthere are many unanswered questions and controversies in the management of OP poisoningand there is an urgent need for research on this aspect of this common and deadly poisoning.Key Words: poisoning, organophosphorus insecticides, decontamination, antidotes

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