The document provides an overview of rheology and its importance in pharmaceutical applications. It discusses key concepts such as:
- Rheology is the study of flow and deformation of matter under stress. It is important for developing dosage forms like liquids, gels, ointments, and creams.
- There are different types of flow patterns (Newtonian, plastic, pseudoplastic, dilatant) based on the relationship between stress and rate of shear. Viscosity and yield value are important parameters.
- Rheological properties influence manufacturing processes and patient acceptability. Selection of equipment depends on flow properties.
- Common techniques to measure viscosity include single point viscometers like Ostwald
Rheology is the science that studies the flow and deformation of matter, especially fluids and semisolids, under stress. The document discusses various rheological concepts including viscosity, Newtonian and non-Newtonian flow, plastic flow, pseudoplastic flow, dilatant flow, thixotropy, and anti-thixotropy. It provides examples of different rheological behaviors exhibited by pharmaceutical formulations like suspensions, emulsions, and gels. Various viscometers used to characterize the rheological properties of such formulations are also described.
This document discusses rheology and the importance of understanding flow properties in pharmaceutical manufacturing and product administration. It defines rheology as the study of flow and deformation of matter under stress. The document covers various types of fluid flow including Newtonian, plastic, pseudoplastic and dilatant. It also discusses thixotropy and measurement of viscosity using single point viscometers like Ostwald and falling sphere, as well as multi-point viscometers like cup and bob and cone and plate. Understanding rheology is important for developing dosage forms and ensuring their proper handling and administration.
This document provides an overview of rheology concepts including:
1. It defines rheology as the science concerned with the deformation of matter under stress.
2. It describes Newtonian and non-Newtonian fluids, explaining that Newtonian fluids have a constant viscosity while non-Newtonian fluids have variable viscosity.
3. It discusses the different types of non-Newtonian flow - plastic, pseudoplastic, and dilatant - and provides examples of materials that exhibit each type of flow.
Rheology is the study of deformation and flow of matter. There are several types of rheological properties including stress, viscosity, viscoelastic modulus, creep, and relaxation times. Rheology is important in manufacturing pharmaceutical dosage forms and applications like ointments, syrups, suspensions, and emulsions where rheological properties influence acceptability, bioavailability, and handling. Materials can exhibit Newtonian, plastic, pseudo-plastic, or dilatant flow depending on the relationship between shear stress and shear rate. Viscometers are used to determine viscosity and classify fluids as Newtonian or non-Newtonian.
Rheology is the study of the flow and deformation of matter under stress. It describes the relationship between force, deformation, and time. The term rheology was coined in 1920 and comes from Greek words meaning "to flow" and "study of". Rheology applies to both liquids and solids, and deals with viscoelastic materials that have properties of both solids and liquids when subjected to forces over time.
Rheology is the study of deformation and flow of matter. It governs the flow of fluids in the body like blood, lymph, and mucus. From a rheological perspective, materials are solids, liquids, or gases depending on whether their shape and volume remain constant under forces. The flow properties of materials determine how easily substances like emulsions and ointments can be processed and used. Materials can exhibit Newtonian or non-Newtonian flow based on whether their viscosity changes with applied stress. Key non-Newtonian flows include plastic, pseudoplastic, and dilatant. Factors like polymer structure, hydration, pH, and temperature affect the rheological properties of pharmaceutical products.
Rheology is the science that studies the flow and deformation of matter, especially fluids and semisolids, under stress. The document discusses various rheological concepts including viscosity, Newtonian and non-Newtonian flow, plastic flow, pseudoplastic flow, dilatant flow, thixotropy, and anti-thixotropy. It provides examples of different rheological behaviors exhibited by pharmaceutical formulations like suspensions, emulsions, and gels. Various viscometers used to characterize the rheological properties of such formulations are also described.
This document discusses rheology and the importance of understanding flow properties in pharmaceutical manufacturing and product administration. It defines rheology as the study of flow and deformation of matter under stress. The document covers various types of fluid flow including Newtonian, plastic, pseudoplastic and dilatant. It also discusses thixotropy and measurement of viscosity using single point viscometers like Ostwald and falling sphere, as well as multi-point viscometers like cup and bob and cone and plate. Understanding rheology is important for developing dosage forms and ensuring their proper handling and administration.
This document provides an overview of rheology concepts including:
1. It defines rheology as the science concerned with the deformation of matter under stress.
2. It describes Newtonian and non-Newtonian fluids, explaining that Newtonian fluids have a constant viscosity while non-Newtonian fluids have variable viscosity.
3. It discusses the different types of non-Newtonian flow - plastic, pseudoplastic, and dilatant - and provides examples of materials that exhibit each type of flow.
Rheology is the study of deformation and flow of matter. There are several types of rheological properties including stress, viscosity, viscoelastic modulus, creep, and relaxation times. Rheology is important in manufacturing pharmaceutical dosage forms and applications like ointments, syrups, suspensions, and emulsions where rheological properties influence acceptability, bioavailability, and handling. Materials can exhibit Newtonian, plastic, pseudo-plastic, or dilatant flow depending on the relationship between shear stress and shear rate. Viscometers are used to determine viscosity and classify fluids as Newtonian or non-Newtonian.
Rheology is the study of the flow and deformation of matter under stress. It describes the relationship between force, deformation, and time. The term rheology was coined in 1920 and comes from Greek words meaning "to flow" and "study of". Rheology applies to both liquids and solids, and deals with viscoelastic materials that have properties of both solids and liquids when subjected to forces over time.
Rheology is the study of deformation and flow of matter. It governs the flow of fluids in the body like blood, lymph, and mucus. From a rheological perspective, materials are solids, liquids, or gases depending on whether their shape and volume remain constant under forces. The flow properties of materials determine how easily substances like emulsions and ointments can be processed and used. Materials can exhibit Newtonian or non-Newtonian flow based on whether their viscosity changes with applied stress. Key non-Newtonian flows include plastic, pseudoplastic, and dilatant. Factors like polymer structure, hydration, pH, and temperature affect the rheological properties of pharmaceutical products.
This document discusses rheology, the science of deformation of matter under stress. It defines tensile and shearing stresses and explains reversible and irreversible deformations. Viscosity is introduced as the resistance of fluids to flow, with Newtonian fluids obeying the law of proportionality between stress and shear rate. Non-Newtonian fluids are divided into time-dependent categories like thixotropy and time-independent types including plastic, pseudoplastic and dilatant flows. Specific examples and rheograms are provided to illustrate different fluid behaviors.
This document discusses rheology, which is the science describing the flow and deformation of matter under stress. It defines key terms like viscosity, shear stress, shear rate, and classifies fluids as Newtonian or non-Newtonian based on their relationship between shear stress and shear rate. Newtonian fluids have a constant viscosity regardless of shear rate, while non-Newtonian fluids have variable viscosity. Plastic, pseudoplastic, and dilatant behaviors are described for non-Newtonian fluids. Thixotropy, which is a time-dependent decrease and recovery of viscosity under shear, is also discussed. The document concludes by explaining the operation and calibration of common viscometers.
This document provides an overview of fluid mechanics concepts including:
- The definition of a fluid and differences between solids and fluids
- Key terminology like stress, shear stress, and boundary layers
- Classifications of fluid flows such as internal vs. external, viscous vs. inviscid, and compressible vs. incompressible
- The no-slip condition and its implications for fluid behavior near surfaces
This document provides an overview of rheology and key rheological concepts. It begins by defining rheology as the study of flow and deformation of materials under stress. It then discusses the importance of rheology for liquid pharmaceutical dosage forms. The document outlines the differences between Newtonian and non-Newtonian fluids, describing Newtonian fluids as having a constant viscosity regardless of stress, while non-Newtonian fluids have a variable viscosity. It provides examples of different types of non-Newtonian fluid flow, including plastic, pseudo-plastic, and dilatant flow. The objectives are to understand these rheological concepts and their significance for pharmaceutical products.
This document discusses rheology and viscosity. It defines rheology as the science of flow of fluids and deformation of solids under stress. Viscosity is a measure of a fluid's resistance to flow and is important in formulation of products like creams, ointments, and suspensions. The document describes different types of fluid flow based on viscosity, such as Newtonian, plastic, and pseudoplastic flow. It also discusses instruments used to measure viscosity like capillary, falling sphere, cup and bob, and cone and plate viscometers. Thixotropy, where the viscosity of a fluid decreases under shear stress over time, is also covered.
This document discusses rheology, which is the branch of physics dealing with the deformation and flow of liquids. It provides definitions and examples of different types of fluid flow, including Newtonian, plastic, pseudoplastic, and dilatant flow. Key aspects covered include viscosity, shear stress, yield value, and the effects of temperature, particle concentration, and other factors on rheological properties. Common instruments used to measure viscosity, such as capillary, falling sphere, cup and bob, and cone and plate viscometers are also described.
Ideal fluid:
a fluid with no friction
Also referred to as an inviscid (zero viscosity) fluid
Internal forces at any section within are normal (pressure forces)
Practical applications: many flows approximate frictionless flow away from solid boundaries.
Real Fluids
Tangential or shearing forces always develop where there is motion relative to solid body
Thus, fluid friction is created
Shear forces oppose motion of one particle past another
Friction forces gives rise to a fluid property called viscosity
SY - PP II - Rheology and Newtons Law of Flow.pdfKeval80
This document discusses rheology, which is the science of deformation and flow of matter. It defines key terms like viscosity, shear stress, and rate of shear. It explains Newton's law of flow and describes Newtonian and non-Newtonian systems. It also discusses factors that affect viscosity like temperature, thixotropy, and different types of viscosity. Finally, it describes common methods to measure and determine viscosity, such as capillary, falling ball, rotational, and other viscometers.
This document discusses fluid mechanics concepts taught in a mechanical engineering course. It defines key terms like fluid, density, viscosity, vapor pressure, and cavitation. It explains that fluids continuously deform under shear stress, unlike solids, and discusses properties of ideal and real fluids. Surface tension and capillarity are also summarized. The document appears to be class notes for an introductory fluid mechanics course in mechanical engineering.
This document discusses fluid mechanics and viscosity. It begins by defining a fluid and explaining that fluids deform continuously under shear forces rather than resist deformation like solids. It then discusses viscosity, defining it as a fluid's resistance to flow. Viscosity exists due to molecular collisions and momentum transfer between layers of a fluid. Methods for measuring viscosity include viscometers that apply shear stresses between fluid layers. Viscosity affects fluid dynamics, causes drag, and is accounted for in the Navier-Stokes equations.
Practical Industrial Flow Measurement for Engineers and TechniciansLiving Online
This document provides an overview of basic fluid properties important for flow measurement. It discusses viscosity and different fluid types, including Newtonian and non-Newtonian fluids. It also describes ideal, laminar and turbulent flow profiles, and how the Reynolds number characterizes these behaviors. Key flow measurement parameters are introduced, such as volumetric and mass flow rates for single and multi-phase flows. The objectives are to describe fluid properties, flow profiles, and flow measurement concepts.
A STUDY ON VISCOUS FLOW (With A Special Focus On Boundary Layer And Its Effects)Rajibul Alam
This document summarizes a study on viscous flow with a focus on boundary layers and their effects. It defines viscosity and describes the boundary layer that forms along a solid surface moving through a fluid. Laminar and turbulent boundary layers are differentiated. The boundary layer equations are presented and used to derive the Navier-Stokes equations that govern viscous fluid flow. Key properties of boundary layers like thickness and velocity profiles are discussed. The interaction of boundary layers and shockwaves is also summarized.
This document summarizes key concepts related to fluid flow phenomena, including:
1) It defines fluids and describes their behavior under applied forces, discussing concepts like potential flow and boundary layers.
2) It outlines different fluid flow regimes for compressible and incompressible fluids, as well as rheological properties of Newtonian and non-Newtonian fluids.
3) It discusses velocity fields, boundary layer formation and properties, and provides an example of a one-dimensional fluid flow through a circular pipe where the velocity depends only on the radial distance from the centerline.
Rheological Properties of Disperse Systems & SemisolidsPriyanka Modugu
This document discusses the rheological properties of disperse systems and semisolids. It begins by introducing disperse systems and classifying them as either colloidal or coarsely dispersed systems. It then discusses various factors that affect the rheology of colloidal dispersions and describes the non-Newtonian flow properties of these systems. The document also addresses the rheological properties of coarsely dispersed systems like suspensions and emulsions. Finally, it covers the rheological evaluation of semisolid dosage forms and how their rheological characteristics influence properties like structure, stability and drug diffusion.
The document outlines learning topics on surface active agents including interface, spreading coefficient, classification, and structural classifications. It discusses how interface is the boundary between phases and how surface active agents are adsorbed at interfaces. Surfactants can be classified based on their hydrophilic-lipophilic balance and function, such as wetting agents, solubilizing agents, and emulsifying agents. The structural classifications of surfactants depend on the number and nature of their hydrophilic and hydrophobic groups.
The document discusses surface and interfacial phenomena. It begins by defining an interface as the boundary between two phases that exist together, such as solid-liquid or liquid-gas. Interfaces can be divided into liquid interfaces and solid interfaces. Liquid interfaces deal with liquid-gas or liquid-liquid phases and have applications in processes like emulsification. Solid interfaces involve solid-gas or solid-liquid boundaries. Several methods are described for measuring properties at interfaces like surface tension, interfacial tension, and surface free energy. Surfactants are introduced as agents that can lower surface tension and interfacial tension. Their structures allow them to concentrate at interfaces.
This document discusses rheology and viscosity measurement techniques. It covers key topics like:
1) Newtonian and non-Newtonian flow, including plastic, pseudoplastic and dilatant systems.
2) Measurement of viscosity using viscometers like capillary, falling sphere and rotational viscometers.
3) Phenomena like thixotropy, antithixotropy and their significance in formulations.
The document provides an overview of important rheological concepts and methods to characterize the flow behavior and viscosity of formulations.
Physical Pharmacy M02 discusses rheology and the measurement of viscosity. It covers Newtonian and non-Newtonian flow, including plastic, pseudoplastic, and dilatant behaviors. Key concepts are thixotropy and antithixotropy. Methods to measure viscosity include capillary, falling sphere, and rotational viscometers. Understanding viscosity is important for formulating drug delivery systems and ensuring patient acceptability.
The document discusses fluids mechanics and provides information about various fluid properties and concepts. It defines fluid, states of matter, density, viscosity, surface tension, capillarity, and vapor pressure. It also discusses fluid pressure and different types of pressure measurements including manometers, mechanical gauges, and electronic gauges. Specific devices like piezometer, U-tube manometer, differential manometer, and bourdon tube pressure gauge are explained. Course outcomes related to understanding and applying concepts of fluid statics, kinematics, dynamics, and pressure measurements are also listed.
1. The document discusses different classes of antidepressant medications, including their mechanisms of action and pharmacology. The main classes covered are tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and monoamine oxidase inhibitors (MAOIs).
2. TCAs work by inhibiting the reuptake of norepinephrine and serotonin, while SSRIs and SNRIs are more selective in inhibiting reuptake. MAOIs work by inhibiting the monoamine oxidase enzyme and preventing breakdown of neurotransmitters.
3. The document reviews the practical applications of antidepressants in treatment of depression and other disorders
Morphine is a natural opioid alkaloid isolated from raw opium in 1805. It has analgesic, anesthetic and other medical uses. Morphine's structure consists of five rings, three in one plane and two perpendicular rings including the nitrogen-containing ring. The phenol and alcohol functional groups, as well as the stereochemistry and nitrogen substitution, are important for morphine's binding and activity. Modifications like acetylation can increase lipid solubility and potency but also toxicity. Replacing the N-methyl group creates the morphine antagonist nalorphine. Morphine's chemical properties underlie its medical uses and abuse potential.
This document discusses rheology, the science of deformation of matter under stress. It defines tensile and shearing stresses and explains reversible and irreversible deformations. Viscosity is introduced as the resistance of fluids to flow, with Newtonian fluids obeying the law of proportionality between stress and shear rate. Non-Newtonian fluids are divided into time-dependent categories like thixotropy and time-independent types including plastic, pseudoplastic and dilatant flows. Specific examples and rheograms are provided to illustrate different fluid behaviors.
This document discusses rheology, which is the science describing the flow and deformation of matter under stress. It defines key terms like viscosity, shear stress, shear rate, and classifies fluids as Newtonian or non-Newtonian based on their relationship between shear stress and shear rate. Newtonian fluids have a constant viscosity regardless of shear rate, while non-Newtonian fluids have variable viscosity. Plastic, pseudoplastic, and dilatant behaviors are described for non-Newtonian fluids. Thixotropy, which is a time-dependent decrease and recovery of viscosity under shear, is also discussed. The document concludes by explaining the operation and calibration of common viscometers.
This document provides an overview of fluid mechanics concepts including:
- The definition of a fluid and differences between solids and fluids
- Key terminology like stress, shear stress, and boundary layers
- Classifications of fluid flows such as internal vs. external, viscous vs. inviscid, and compressible vs. incompressible
- The no-slip condition and its implications for fluid behavior near surfaces
This document provides an overview of rheology and key rheological concepts. It begins by defining rheology as the study of flow and deformation of materials under stress. It then discusses the importance of rheology for liquid pharmaceutical dosage forms. The document outlines the differences between Newtonian and non-Newtonian fluids, describing Newtonian fluids as having a constant viscosity regardless of stress, while non-Newtonian fluids have a variable viscosity. It provides examples of different types of non-Newtonian fluid flow, including plastic, pseudo-plastic, and dilatant flow. The objectives are to understand these rheological concepts and their significance for pharmaceutical products.
This document discusses rheology and viscosity. It defines rheology as the science of flow of fluids and deformation of solids under stress. Viscosity is a measure of a fluid's resistance to flow and is important in formulation of products like creams, ointments, and suspensions. The document describes different types of fluid flow based on viscosity, such as Newtonian, plastic, and pseudoplastic flow. It also discusses instruments used to measure viscosity like capillary, falling sphere, cup and bob, and cone and plate viscometers. Thixotropy, where the viscosity of a fluid decreases under shear stress over time, is also covered.
This document discusses rheology, which is the branch of physics dealing with the deformation and flow of liquids. It provides definitions and examples of different types of fluid flow, including Newtonian, plastic, pseudoplastic, and dilatant flow. Key aspects covered include viscosity, shear stress, yield value, and the effects of temperature, particle concentration, and other factors on rheological properties. Common instruments used to measure viscosity, such as capillary, falling sphere, cup and bob, and cone and plate viscometers are also described.
Ideal fluid:
a fluid with no friction
Also referred to as an inviscid (zero viscosity) fluid
Internal forces at any section within are normal (pressure forces)
Practical applications: many flows approximate frictionless flow away from solid boundaries.
Real Fluids
Tangential or shearing forces always develop where there is motion relative to solid body
Thus, fluid friction is created
Shear forces oppose motion of one particle past another
Friction forces gives rise to a fluid property called viscosity
SY - PP II - Rheology and Newtons Law of Flow.pdfKeval80
This document discusses rheology, which is the science of deformation and flow of matter. It defines key terms like viscosity, shear stress, and rate of shear. It explains Newton's law of flow and describes Newtonian and non-Newtonian systems. It also discusses factors that affect viscosity like temperature, thixotropy, and different types of viscosity. Finally, it describes common methods to measure and determine viscosity, such as capillary, falling ball, rotational, and other viscometers.
This document discusses fluid mechanics concepts taught in a mechanical engineering course. It defines key terms like fluid, density, viscosity, vapor pressure, and cavitation. It explains that fluids continuously deform under shear stress, unlike solids, and discusses properties of ideal and real fluids. Surface tension and capillarity are also summarized. The document appears to be class notes for an introductory fluid mechanics course in mechanical engineering.
This document discusses fluid mechanics and viscosity. It begins by defining a fluid and explaining that fluids deform continuously under shear forces rather than resist deformation like solids. It then discusses viscosity, defining it as a fluid's resistance to flow. Viscosity exists due to molecular collisions and momentum transfer between layers of a fluid. Methods for measuring viscosity include viscometers that apply shear stresses between fluid layers. Viscosity affects fluid dynamics, causes drag, and is accounted for in the Navier-Stokes equations.
Practical Industrial Flow Measurement for Engineers and TechniciansLiving Online
This document provides an overview of basic fluid properties important for flow measurement. It discusses viscosity and different fluid types, including Newtonian and non-Newtonian fluids. It also describes ideal, laminar and turbulent flow profiles, and how the Reynolds number characterizes these behaviors. Key flow measurement parameters are introduced, such as volumetric and mass flow rates for single and multi-phase flows. The objectives are to describe fluid properties, flow profiles, and flow measurement concepts.
A STUDY ON VISCOUS FLOW (With A Special Focus On Boundary Layer And Its Effects)Rajibul Alam
This document summarizes a study on viscous flow with a focus on boundary layers and their effects. It defines viscosity and describes the boundary layer that forms along a solid surface moving through a fluid. Laminar and turbulent boundary layers are differentiated. The boundary layer equations are presented and used to derive the Navier-Stokes equations that govern viscous fluid flow. Key properties of boundary layers like thickness and velocity profiles are discussed. The interaction of boundary layers and shockwaves is also summarized.
This document summarizes key concepts related to fluid flow phenomena, including:
1) It defines fluids and describes their behavior under applied forces, discussing concepts like potential flow and boundary layers.
2) It outlines different fluid flow regimes for compressible and incompressible fluids, as well as rheological properties of Newtonian and non-Newtonian fluids.
3) It discusses velocity fields, boundary layer formation and properties, and provides an example of a one-dimensional fluid flow through a circular pipe where the velocity depends only on the radial distance from the centerline.
Rheological Properties of Disperse Systems & SemisolidsPriyanka Modugu
This document discusses the rheological properties of disperse systems and semisolids. It begins by introducing disperse systems and classifying them as either colloidal or coarsely dispersed systems. It then discusses various factors that affect the rheology of colloidal dispersions and describes the non-Newtonian flow properties of these systems. The document also addresses the rheological properties of coarsely dispersed systems like suspensions and emulsions. Finally, it covers the rheological evaluation of semisolid dosage forms and how their rheological characteristics influence properties like structure, stability and drug diffusion.
The document outlines learning topics on surface active agents including interface, spreading coefficient, classification, and structural classifications. It discusses how interface is the boundary between phases and how surface active agents are adsorbed at interfaces. Surfactants can be classified based on their hydrophilic-lipophilic balance and function, such as wetting agents, solubilizing agents, and emulsifying agents. The structural classifications of surfactants depend on the number and nature of their hydrophilic and hydrophobic groups.
The document discusses surface and interfacial phenomena. It begins by defining an interface as the boundary between two phases that exist together, such as solid-liquid or liquid-gas. Interfaces can be divided into liquid interfaces and solid interfaces. Liquid interfaces deal with liquid-gas or liquid-liquid phases and have applications in processes like emulsification. Solid interfaces involve solid-gas or solid-liquid boundaries. Several methods are described for measuring properties at interfaces like surface tension, interfacial tension, and surface free energy. Surfactants are introduced as agents that can lower surface tension and interfacial tension. Their structures allow them to concentrate at interfaces.
This document discusses rheology and viscosity measurement techniques. It covers key topics like:
1) Newtonian and non-Newtonian flow, including plastic, pseudoplastic and dilatant systems.
2) Measurement of viscosity using viscometers like capillary, falling sphere and rotational viscometers.
3) Phenomena like thixotropy, antithixotropy and their significance in formulations.
The document provides an overview of important rheological concepts and methods to characterize the flow behavior and viscosity of formulations.
Physical Pharmacy M02 discusses rheology and the measurement of viscosity. It covers Newtonian and non-Newtonian flow, including plastic, pseudoplastic, and dilatant behaviors. Key concepts are thixotropy and antithixotropy. Methods to measure viscosity include capillary, falling sphere, and rotational viscometers. Understanding viscosity is important for formulating drug delivery systems and ensuring patient acceptability.
The document discusses fluids mechanics and provides information about various fluid properties and concepts. It defines fluid, states of matter, density, viscosity, surface tension, capillarity, and vapor pressure. It also discusses fluid pressure and different types of pressure measurements including manometers, mechanical gauges, and electronic gauges. Specific devices like piezometer, U-tube manometer, differential manometer, and bourdon tube pressure gauge are explained. Course outcomes related to understanding and applying concepts of fluid statics, kinematics, dynamics, and pressure measurements are also listed.
1. The document discusses different classes of antidepressant medications, including their mechanisms of action and pharmacology. The main classes covered are tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and monoamine oxidase inhibitors (MAOIs).
2. TCAs work by inhibiting the reuptake of norepinephrine and serotonin, while SSRIs and SNRIs are more selective in inhibiting reuptake. MAOIs work by inhibiting the monoamine oxidase enzyme and preventing breakdown of neurotransmitters.
3. The document reviews the practical applications of antidepressants in treatment of depression and other disorders
Morphine is a natural opioid alkaloid isolated from raw opium in 1805. It has analgesic, anesthetic and other medical uses. Morphine's structure consists of five rings, three in one plane and two perpendicular rings including the nitrogen-containing ring. The phenol and alcohol functional groups, as well as the stereochemistry and nitrogen substitution, are important for morphine's binding and activity. Modifications like acetylation can increase lipid solubility and potency but also toxicity. Replacing the N-methyl group creates the morphine antagonist nalorphine. Morphine's chemical properties underlie its medical uses and abuse potential.
Morphine and fentanyl are potent opioid analgesics that act on mu-opioid receptors in the central nervous system and peripheral tissues to provide pain relief. Morphine is a naturally occurring substance extracted from poppy plants, while fentanyl is a synthetic opioid. Both have a rapid onset but morphine's effects last 3-6 hours while fentanyl's last 30-60 minutes. Common side effects include respiratory depression, nausea, constipation, and euphoria. Tolerance can develop with long-term use requiring higher doses for pain management.
This document summarizes opioids including their classification, clinical uses, pharmacokinetics, mechanisms of action, effects, side effects, and toxicity. It discusses strong opioids like morphine, moderate opioids like codeine, and weak opioids like propoxyphene. It covers how opioids produce analgesia by binding to G protein coupled receptors in the brain and spinal cord, their metabolism and elimination, and their respiratory depressant effects.
Carbamazepine is an anticonvulsant medication used to treat seizures and neuropathic pain. It comes in tablet, capsule, suspension, and extended release forms. Common dosages and administration guidelines are provided for different conditions and age groups. Adverse effects, drug interactions, contraindications and monitoring parameters are outlined. Black box warnings include risks of aplastic anemia and agranulocytosis with therapy.
This document discusses pre-anaesthetic medication, general anaesthetic agents, and their history, mechanisms, and complications. It provides an overview of drugs used for pre-medication including anxiolytics, sedatives, opioids, anticholinergics, and antiemetics. It then discusses the history and stages of general anaesthesia and properties of common inhalational agents like ether, nitrous oxide, halothane, enflurane, isoflurane, and sevoflurane. It also summarizes intravenous induction agents like thiopentone and propofol and discusses their pharmacokinetics, mechanisms of action, advantages, and disadvantages.
Adrenaline and noradrenaline are catecholamines that act as hormones and neurotransmitters. They are synthesized from tyrosine and phenylalanine through a series of enzymatic reactions. Adrenaline acts on alpha-1, alpha-2, and beta receptors and causes effects like increased heart rate, vasoconstriction, bronchodilation and glycogenolysis. Noradrenaline predominantly acts on alpha-1 and beta-1 receptors, causing potent vasoconstriction with little bronchodilation. Both are used to treat hypotension, cardiac arrest and anaphylaxis. Their administration must be closely monitored due to risks of hypertension, arrhythmias and tissue necrosis from vasoconstrict
Adrenaline is used to treat anaphylaxis, hypotension, bronchospasm, cardiac arrest, and asystole. It works by causing smooth muscle relaxation in the airways, contraction in the arterioles, and increasing contractability of cardiac muscles. Common side effects include hypertension, tachycardia, anxiety, dysrhythmias, dizziness, pallor, tremor, insomnia, headache, nausea, and palpitations. When administering adrenaline, nurses must follow ten rights, monitor for adverse effects, and use caution in patients with certain medical conditions.
This document summarizes a seminar presentation on sympathomimetic drugs. It describes how these drugs act directly or indirectly on alpha and beta adrenergic receptors to mimic the effects of epinephrine and sympathetic stimulation. It provides details on the actions of various sympathomimetics in tissues and organ systems. Therapeutic uses are outlined for pressor agents, cardiac stimulants, bronchodilators, nasal decongestants, CNS stimulants, and anorectics. Important drugs like dopamine, dobutamine, ephedrine, and phenylephrine are also described in terms of their clinical applications, dosages, and formulations.
This document provides an overview of adrenaline (epinephrine) including its biosynthesis, types of adrenoreceptors, pharmacological effects, uses, contraindications, and administration. Adrenaline is a hormone and neurotransmitter produced by the adrenal glands that is responsible for the fight or flight response. It acts on alpha and beta adrenoreceptors to increase heart rate and cardiac output, bronchodilation, glycogenolysis, and lipolysis. Common uses include treatment of anaphylaxis, bronchospasm, and severe hypotension. It can cause anxiety, headache, and arrhythmias and is contraindicated in patients with hypertension, angina, or who are taking beta-blockers.
This document provides an overview of the heterocyclic compound pyrrole. It begins with an introduction to heterocyclic compounds and defines pyrrole. The document then covers the nomenclature, physical properties, chemical properties and reactions, derivatives, and various methods of synthesizing pyrrole. Applications of pyrrole are also discussed. Key points include that pyrrole is aromatic, contains a 5-membered ring with one nitrogen atom, and is present in many natural products and pharmaceuticals. Pyrrole undergoes electrophilic substitution reactions and exhibits aromatic character due to resonance stabilization.
The document discusses colloidal dispersions, which are systems where particles ranging from 1 nm to 1 μm are dispersed uniformly throughout a dispersion medium. Colloidal systems are classified based on particle size as molecular, colloidal, or coarse dispersions. Examples of colloidal systems encountered in pharmacy include micelles, emulsions, suspensions, and aerosols. Colloidal particles exhibit properties like the Tyndall effect (scattering of light) and Brownian motion due to bombardment by dispersion medium molecules.
Main Java[All of the Base Concepts}.docxadhitya5119
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.
How to Build a Module in Odoo 17 Using the Scaffold MethodCeline George
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
How to Fix the Import Error in the Odoo 17Celine George
An import error occurs when a program fails to import a module or library, disrupting its execution. In languages like Python, this issue arises when the specified module cannot be found or accessed, hindering the program's functionality. Resolving import errors is crucial for maintaining smooth software operation and uninterrupted development processes.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
3. INTRODUCTION
rheo – to flow
logos – science
Rheology is the study of the flow and deformation of matter under
stress.
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4. DEFINITION OF RHEOLOGY
Rheology is the science/physics that concerns with the flow of
liquids and the deformation of solids.
Study of flow properties of liquids is important for pharmacist
working in the manufacture of several dosage forms, viz., simple
liquids, gels, ointments, creams, and pastes.
These systems change their flow behavior when exposed to
different stress conditions.
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5. IMPORTANCE & FUNDAMENTALS
Formulation of medicinal and cosmetic creams, pastes and lotions.
Formulation of emulsions, suspensions, suppositories, and tablet
coating.
Fluidity of solutions for injection.
In mixing and flow of materials, their packaging into the containers,
their removal prior to use, the pouring from the bottle.
Extrusion of a paste from a tube .
Passage of the liquid to a syringe needle.
Influence the choice of processing equipments in the pharmaceutical
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6. • Can affect the patient’s acceptability of the product, physical stability,
biologic availability, absorption rate of drugs in the gastrointestinal
tract.
• Manufacturing of dosage forms: Materials undergo process such as
mixing, flowing through pipes, filling into the containers etc. Flow
related changes influence the selection of mixing equipment.
• Handling of drugs for administration: The syringibility of the
medicines, the pouring of the liquids from containers, extrusion of
ointment from tubes, all depend on the changes in flow behavior of
dosage forms.
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7. NEWTONS LAW
According to NEWTONS LAW higher the
viscosity of a liquid, the greater is the force per
unit area (shearing stress F) required to produce a
certain rate of shear( G).
rate of shear α shearing stress
F= ῃ G
Where
F= F’/ A
G= dv/ dr
ῃ= viscosity
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9. NEWTONIAN FLOW:
A Newtonian fluid (named for Isaac Newton) is a fluid whose stress
versus rate of shear curve is linear and passes through the origin. The
constant of proportionality is known as the viscosity.
Examples :
Water,
chloroform,
Castor oil,
ethyl Alcohol etc.
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10. VISCOSITY
It is defined as resistance to the flow.
ῃ is the coefficient of viscosity. And is calculated
as
ῃ=F/ G
Where F= Shearing stress
G= Rate of shear
o Unit of viscosity is Poise or dyne.sec/cm2.
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11. NON NEWTONIAN FLOW
• A non newtonian flow is defined as one for which the relation
between F and S is not linear.
• In other words when the shear rate is varied, the shear stress is not
varied in the same proportion. The viscosity of such a system thus
varies as the shearing stress varies.
• It can be seen in liquids and in solid heterogeneous dispersions
such as emulsions, suspensions, colloids and ointments.
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13. PLASTIC FLOW:
• In which curve does not pass through the origin, the substance behaves
initially
• Elastic body and it fails to flow when less amount of stress is applied.
• As increase the stress, leads to non-linear increase in shear rate but after that
curve is linear.
• The linear portion extrapolated intersects the x axis at the point called as
yield value
So, plastic flow shows Newtonian flow above the yield value.
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14. •The curve represents plastic flow, such materials are called as Bingham
bodies.
•Bingham bodies does not flow until the shearing stress is corresponding to
yield Value exceeded.
•So, yield value is important property of certain dispersions.
•The reciprocal of mobility is Plastic viscosity
EXAMPLES: ZnO in mineral oil, certain pastes , paints and ointments.
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15. Plastic flow explained by flocculated particles in
concentrated suspensions, ointments, pastes and gels.
Flocculated Individual
Particles particles
Yield value
Increase
stress
Flow
F/A
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16. PLASTIC FLOW
The curve for the plastic flow is as fallows.
Shearing
stress, F
Rate of shear,
G Yield value
Slope =
mobility
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17. The equation describing plastic flow is,
Where,
f = Yield value
F = Shearing stress
G = Rate of shear
U = F – f / G
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18. PSEUDO PLASTIC FLOW
Many P’ceutical products liquid dispersion of natural and synthetic
gums shows pseudo plastic flow.
eg. 1. Tragacanth in water
2. Sod. Alginate in water
3. Methyl cellulose in water
4. Sodium CMC in water
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19. • With increase in the shearing stress the disarranged molecules
orient themselves in the direction of flow, thus reducing friction
and allows a greater rate of shear at each shearing stress.
• Some of the solvent associated will be released resulting in
decreased viscosity.
• This type of flow behavior is also called as shear thinning
system.
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20. Graph for pseudo plastic flow is like this
In which curve is passing from origin (Zero shear stress), so no yield
value is Obtained.
As shear stress increases, shear rate increases but not
linear.
Shearing
stress, F
Rate of shear,
G
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21. Pseudo plastic flow can be explained by Long chain
molecules of polymer.
In storage condition, arrange randomly in dispersion.
Water
Stress
Polymer long chain
with water molecules
Polymer & water molecules
align on direction of force
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22. On applying F/A, shearing stress molecules ( water &
polymer) arrange long axis in the direction of force applied.
This stress reduces internal resistance & solvent molecules
released form polymer molecules.
Then reduce the concentration and size of molecules with
decrease in viscosity.
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23. The exponential equation shows this flow
N = no. of given exponent
η = Viscosity coefficient
In case of pseudo plastic flow, N > 1.
i.e. More N >1, the greater pseudo plastic flow of material.
If N = 1, the flow is Newtonian.
FN = η G
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24. Taking Log on both sides,
i.e.
On rearrangement, we get
This equation gives straight line,
N log F = log η + log G
log G = N log F - log η
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25. DILATANT FLOW
Certain suspensions with high % of dispersed solids shows an
increase in resistance to flow with increasing rates of shear, such
system increase in volume when sheared, such system called as
dilatant flow.
Also, called as “ Shear thickening system” i.e. when stress is
removed, dilatant system return to its original position
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26. Graph for dilatant flow is like this
In which curve is passing from origin (Zero shear stress), so no yield
value is Obtained.
Non-linear increase in rate of shear.
Increase resistance to flow on increase rate of shear
Shearing stress, F
Rate of shear, G
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27. In which, particles are closely packed with less voids spaces,
also amount of vehicle is sufficient to fill the void volume.
This leads particles to move relative to one another at low rate of shear.
At rest close packed Less
void volume Sufficient
vehicle Low consistency
Open packed High void
volume Insufficient
vehicle High
consistency
Increase rate of
shear
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28. So therefore, dilatant suspension can be poured from bottle because in these
condition it is fluid.
When stress is increased, the particles shows the open packing and bulk of
system (void volume is increase) is increased.
But the amount of vehicle is insufficient to fill this void space.
Thus particles are not wetted or lubricated and develop resistance to flow.
Finally system show the paste like consistency.
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29. Because of this type of behavior, the dilatant suspension can be
process by high speed mixers, blenders or mills.
The exponential equation shows this flow
N = no. of given exponent
η = Viscosity coefficient
In which N < 1, and decrease as the dilatancy increase.
If N = 1, the system is Newtonian flow
FN = η G
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30. THIXOTROPHY (GEL-SOL-GEL)
It is defined as, isothermal and comparatively slow recovery on standing of
material of a consistency lost through shearing.
It is shear thinning system, when agitated and kept aside it is expected to
return its original state of fluidity, but takes longer time to recover
compared to the time taken for agitation.
Thixotropic behavior can be shown by plastic and pseudo plastic system.
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31. THIXOTROPHY CONCEPT (PARTICLE – PARTICLE
INTERACTIONS) (GEL – SOL – GEL TRANSFORMATION)
Multi point contacts
(High consistency
or high viscosity)
Contacts break down
(low consistency
or low viscosity)
Particle contacts form
due to brownian motion
At rest
( On storage)
Gel state
On shear
(equilibrium) Sol state
Gel state
Set aside
(removal of
stress)
Rapid
process
slow process
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32. The Rheogram of thixotropic material depends on:
Rate at which shear increased or decreased.
Length of time during which sample is subjected to any one rate of
shear.
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33. The thixotrophy phenomena can be
observed by constructing
consistency curves.
From the graph up curve ab is
obtained, up to maximum point b.
If the rate of shear is reduced,
then down curve bc is obtained.
In Non-Newtonian system, the
down curve is displaced to left of
the up curve.
In this graph, the material has low
consistency at any rate of shear on
down curve compared to that
shown on up curve.
lly, thixotropic curves constructed
for pseudo plastic system .
In Newtonian system, down curve
superimposed to up curve.
Shear stress, F
Rate
of
shear,
G
a
b
c
Plastic
system
Pseudo plastic
system
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34. ANTI-THIXOTROPHY (-VE THIXOTROPHY)
Anti-thixotrophy represents an increase in consistency (high viscosity) rather
decrease in consistency in the down curve.
The increase in thickness or resistance to flow with increase time of shear
observed for (magnesia magma).
Anti – thixotrophy is flocculated system containing low solid content ( 1 – 10
%).
Dilatancy system is deflocculated system containing solid content ( > 50 %).
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35. Individual particles
(in large no. Of small flocs)
(Low viscosity)
Particle collision &
contacts are more
(Large flocs in small no.)
( High viscosity)
Flocs contacts break
individual particles
(Low viscosity)
At rest
( On storage)
On shear
(equilibrium)
Sol state
Set aside
(removal of
stress)
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36. THE ANTI -
THIXOTROPHY
PHENOMENA CAN
BE SHOWN BY
MAGNESIA MAGMA
A B C
D
From the Rheogram it is observed
that,
When Magnesia magma was
alternatively sheared at sing and
sing rate of shear, magma got
thick continuously.
Finally, reach the equilibrium
state in which, further cycling of
sing and sing rate of shear no
longer sing consistency of
material.
Equilibrium state where gel was
found.
When allow to stand, material
return to sol like property.
Shear stress, F
Rate
of
shear,
G
UP
curve
Down
curve
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37. RHEOPEXY
Rheopexy is phenomena in which a sol forms a gel more readily
when shaken or sheared than when allow to form the gel while the
material is kept at rest.
e.g. Magnesia magma, Clay suspension
In rheopectic system, the gel is the equilibrium state.
In anti – thixotropic system, the sol is the equilibrium state.
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38. MEASUREMENT OF THIXOTROPHY
The most apparent characteristics of thixotropic system is the Hysteresis
loop formed by up curve & down curves of the rheograms.
The area of Hysteresis loop has been used to measure the thixotropic
breakdown and can be obtained by means of Planimeter.
With plastic ( Bingham ) bodies; two approaches are used to estimate
degree of thixotrophy.
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39. Two approaches
To determine Structural breakdown with time at constant rate of
shear
To determine Structural breakdown due to increasing shear
rate.
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41. DETERMINATION OF RHEOLOGIC
(FLOW) PROPERTIES
Selection of viscometer
Single point viscometer Multi point
viscometer
Ostwald viscometer Cup and bob
viscometer
Falling sphere viscometer Cone and plate
viscometer
Principle Principle
Stress α rate of shear Viscosity det. at several
Equipment works at rates of shear to get
Single rate of shear consistency curves
Application Application
Newtonian flow non -Newtonian flow
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42. SINGLE POINT VISCOMETERS
Ostwald viscometer (Capillary)
The Ostwald viscometer is used to
determine the viscosity of Newtonian
fluid.
The viscosity of Newtonian fluid is
determined by measuring time required
for the fluid to pass between two marks.
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43. Principle: When a liquid flows by gravity, the time required for
the liquid to pass between two marks ( A & B) through the
vertical capillary tube. the time of flow of the liquid under test
is compared with time required for a liquid of known viscosity
(Water).
Therefore, the viscosity of unknown liquid
(η1
) can be determined by using following
equation:
eq.1
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44. Where,
ρ1 = density of unknown liquid
ρ2 = density of known liquid
t1 = time of flow for unknown liquid
t2 = time of flow for known liquid
η2
= viscosity of known liquid
Eq. 1 is based on the Poiseuille’s law express the following relationship
for the flow of liquid through the capillary viscometer.
Where,
r = radius of capillary, t = time of flow, Δ P = pressure head dyne/cm2 ,
l = length of capillary cm, V = volume of liquid flowing, cm3
η = П r2 t Δ P / 8 l V Eq:2
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45. For a given Ostwald viscometers, the r, V and l are combine into constant (K),
then eq. 2 can be written as,
In which,
The pressure head ΔP ( shear stress) depends on the density of liquid being
measured, acceleration due to gravity (g) and difference in heights of liquid
in viscometers.
Acceleration of gravity is constant, & if the levels in capillary are kept constant
for all liquids,
η = KtΔP Eq.3
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46. If these constants are incorporate into the eq. 3 then,
viscosity of liquids may be expressed as:
On division of eq. 4 and 5 gives the eq .1, which is given in
the principle,
η1 = K’t1 ρ1 eq. 4
η2 = K’t2 ρ2 eq. 5
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47. Equation.6, may be used to determine the relative and
absolute viscosity of liquid.
This viscometer, gives only mean value of
viscosity because one value of pressure head is
possible.
Ostwald viscometer is used for highly
viscous fluid i.e. Methyl cellulose
Dispersions
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48. FALLING SPHERE VISCOMETERS
It is called as Hoeppler falling sphere viscometers.
Principle: A glass or ball rolls down in vertical glass tube
containing the test liquid at a known constant temperature. The rate at
which the ball of particular density and diameter falls is an inverse
function of viscosity of sample.
Construction:
Glass tube position vertically.
Constant temperature jacket
with Water circulation around
glass tube
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49. Working: A glass or steel ball is dropped into the liquid & allowed to reach
equilibrium with temprature of outer jacket. The tube with jacket is then
inverted so that, ball at top of the inner glass tube. the time taken by the ball
to fall between two marks is measured, repeated process for several times to
get concurrent results. For better results select ball which takes NLT 30 sec.
to fall between two marks.
Where,
t = time in sec.for ball to fall between two marks
Sb & Sf = Specific gravities of ball and fluid under
examination.
B = Constant for particular ball.
η = t ( Sb – Sf ) B
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50. MULTI POINT VISCOMETERS
(ROTATIONAL)
Cup and Bob
Various instruments are available, differ mainly whether
torque results from rotation of cup or bob.
Couette type viscometers: Cup is rotated, the viscous drag on the bob
due to sample causes to turn. The torque is proportional to viscosity of
sample.
Ex. McMichael viscometer
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51. Searle type viscometers: Bob is rotated, the torque resulting from the
viscous drag of the system under examination is measured by spring or
sensor in the drive to the bob.
Ex. Stormer viscometer
Working: The test sample is place in space between cup and bob & allow
to reach temperature equilibrium. A weight is place in hanger and record
the time to make 100 rotations by bob, convert this data to rpm. This
value represents the shear rate, same procedure repeated by increasing
weight.
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52. So then plotted the rheogram rpm Vs weights the rpm values
converted to actual rate of shear and weight converted into
units of shear stress, dy/cm2 by using appropriate constants.
Mathematical treatment:
For, rotational viscometers, the relationship can be expressed as,
η = Kv w/v
where
v, rpm generated by weight w, in gm
Kv is obtained by analyzing material of known viscosity in poise.
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53. Cone and plate viscometer (Rotational viscometer)
Principle: The sample is placed on at the
center of the plate, which is raised into
the position under the cone.
The cone is driven by variable speed
motor and sample is sheared in the narrow
gap between stationary plate and rotating cone.
Rate of shear in rpm is increased & decrease by selector dial and
viscous traction or torque (shearing stress) produced on the
cone.
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54. Viscosity for Newtonian system can be estimated by,
Where,
C = Instrument constant,
T = Torque reading & V = Speed of the cone (rpm)
Plastic viscosity determined by,
Yield value (f) = Cf × Tf
Tf = Torque at shearing stress axis (extrapolate from linear
portion of curve). Cf = Instrument constant
η = C T/V eq.1
U = Cf T – Tf / v eq.2
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55. PHARMACEUTICALAPPLICATIONS
1. The viscosity of creams and lotions may affect the rate of absorption of the
products by the skin.
2. A greater release of active ingredients is generally possible from the softer,
less viscous bases.
3. The viscosity of semi-solid products may affect absorption of these topical
products due to the effect of viscosity on the rate of diffusion of the active
ingredients.
4. The rate of absorption of an ordinary suspension differs from thixotropic
suspension.
5. Thixotropy is useful in the formulation of pharmaceutical suspensions and
emulsions. They must be poured easily from containers (low viscosity)
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