This document discusses size reduction, which is the process of reducing substances into smaller pieces or particles through mechanical means. It describes the objectives and mechanisms of size reduction and factors that affect the process. Several common size reduction machines are also outlined, including their principles, construction, uses, advantages, and disadvantages. Size reduction is an important pharmaceutical process that improves properties like dissolution rate and bioavailability by increasing surface area.
Definition of drying
Importance of drying
Difference between drying and evaporation
Drying is defined as removal of the liquid from a material by application of heat & is accomplished by transfer of a liquid from the surface into an unsaturated vapor phase .
Drying is the final removal of water from material (usually by heat)
Drying is commonly the last stage in a manufacture process
Non-thermal drying
1- As Squeezing wetted sponge
2- Adsorption by desiccant (desiccation)
3- Extraction.
Preservation of drug products
Preparation of bulk drugs
Improved handling
Improved characteristics
Equipments
Drying is necessary in order to avoid deterioration. A few examples are…
--blood products, tissues… undergo microbial growth
--effervescent tablets, synthetic & semi synthetic drugs undergo…. chemical decomposition.
Size separation, also known as screening or sieving, involves separating particles into two or more portions based on differences in particle size, shape, and density. This is done using screening surfaces with meshes of different sizes. Common methods of size separation include sieving using oscillation, vibration, gyration, brushing, or centrifugal force to separate particles. Size separation is useful for obtaining specific particle size ranges for applications like tablet and capsule production.
This document discusses size separation techniques used to separate particles of different sizes. Size separation, also known as sieving or screening, is important to obtain particles of a narrow size range or uniform particle size. It improves properties like mixing, flow, and suspension stability. Common mechanisms of size separation include agitation (oscillation, vibration, gyration), brushing, and centrifugal forces. Standard sieves made of woven wire or mesh are used to separate particles according to their ability to pass through openings of different sizes. Instruments like sieve shakers, cyclones, air separators, and filter bags can be employed for size separation in pharmaceutical applications.
This document discusses various methods for size separation of powders, as outlined in the Indian Pharmacopoeia. It describes 5 grades of powder sizes defined by the IP based on their ability to pass through various mesh sieves. Common separation techniques include sieving, cyclone separation, air separation, and elutriation. Sieving involves using a set of sieves arranged from largest to smallest mesh size to separate powder fractions. Cyclone and air separators use centrifugal forces to separate solids from gases. Elutriation separates powders based on particle density differences in a moving fluid.
This document discusses different drying methods used in pharmaceutical applications. It describes tray dryers and fluidized bed dryers. Tray dryers consist of cabinets with trays that allow heated air to circulate and dry materials placed on the trays. Fluidized bed dryers suspend materials in a fluidized state using heated air blown through a removable bowl, allowing for rapid drying. Both methods are used to dry granules for tablets and powders, with fluidized bed dryers being faster but risking electrostatic charges or attrition in some materials.
Mixing is the process of combining two or more components through agitation to create a uniform mixture. There are several types of mixers that can be used for different applications depending on whether solids, liquids, or semisolids are being mixed. The key goals of mixing are to obtain a uniform composition and enhance reactions between components. Factors like particle size and shape, density, mixing time and mechanism influence the mixing process. Homogenization further breaks down mixtures to reduce particle size and create a more uniform dispersion.
The climbing film evaporator uses long, narrow steam-jacketed tubes to heat and evaporate liquid. As the preheated liquid rises through the tubes, bubbles form and coalesce into larger bubbles that trap liquid and rise as well. This forms a liquid film on the tube walls that rapidly vaporizes. The mixture of vapor and entrained liquid is then separated by an entrainment separator at the top, with vapor exiting and concentrated liquid collected below. Climbing film evaporators are well-suited for heat-sensitive and foaming liquids due to their short contact time and ability to break foam. However, they are also expensive to construct and maintain.
Definition of drying
Importance of drying
Difference between drying and evaporation
Drying is defined as removal of the liquid from a material by application of heat & is accomplished by transfer of a liquid from the surface into an unsaturated vapor phase .
Drying is the final removal of water from material (usually by heat)
Drying is commonly the last stage in a manufacture process
Non-thermal drying
1- As Squeezing wetted sponge
2- Adsorption by desiccant (desiccation)
3- Extraction.
Preservation of drug products
Preparation of bulk drugs
Improved handling
Improved characteristics
Equipments
Drying is necessary in order to avoid deterioration. A few examples are…
--blood products, tissues… undergo microbial growth
--effervescent tablets, synthetic & semi synthetic drugs undergo…. chemical decomposition.
Size separation, also known as screening or sieving, involves separating particles into two or more portions based on differences in particle size, shape, and density. This is done using screening surfaces with meshes of different sizes. Common methods of size separation include sieving using oscillation, vibration, gyration, brushing, or centrifugal force to separate particles. Size separation is useful for obtaining specific particle size ranges for applications like tablet and capsule production.
This document discusses size separation techniques used to separate particles of different sizes. Size separation, also known as sieving or screening, is important to obtain particles of a narrow size range or uniform particle size. It improves properties like mixing, flow, and suspension stability. Common mechanisms of size separation include agitation (oscillation, vibration, gyration), brushing, and centrifugal forces. Standard sieves made of woven wire or mesh are used to separate particles according to their ability to pass through openings of different sizes. Instruments like sieve shakers, cyclones, air separators, and filter bags can be employed for size separation in pharmaceutical applications.
This document discusses various methods for size separation of powders, as outlined in the Indian Pharmacopoeia. It describes 5 grades of powder sizes defined by the IP based on their ability to pass through various mesh sieves. Common separation techniques include sieving, cyclone separation, air separation, and elutriation. Sieving involves using a set of sieves arranged from largest to smallest mesh size to separate powder fractions. Cyclone and air separators use centrifugal forces to separate solids from gases. Elutriation separates powders based on particle density differences in a moving fluid.
This document discusses different drying methods used in pharmaceutical applications. It describes tray dryers and fluidized bed dryers. Tray dryers consist of cabinets with trays that allow heated air to circulate and dry materials placed on the trays. Fluidized bed dryers suspend materials in a fluidized state using heated air blown through a removable bowl, allowing for rapid drying. Both methods are used to dry granules for tablets and powders, with fluidized bed dryers being faster but risking electrostatic charges or attrition in some materials.
Mixing is the process of combining two or more components through agitation to create a uniform mixture. There are several types of mixers that can be used for different applications depending on whether solids, liquids, or semisolids are being mixed. The key goals of mixing are to obtain a uniform composition and enhance reactions between components. Factors like particle size and shape, density, mixing time and mechanism influence the mixing process. Homogenization further breaks down mixtures to reduce particle size and create a more uniform dispersion.
The climbing film evaporator uses long, narrow steam-jacketed tubes to heat and evaporate liquid. As the preheated liquid rises through the tubes, bubbles form and coalesce into larger bubbles that trap liquid and rise as well. This forms a liquid film on the tube walls that rapidly vaporizes. The mixture of vapor and entrained liquid is then separated by an entrainment separator at the top, with vapor exiting and concentrated liquid collected below. Climbing film evaporators are well-suited for heat-sensitive and foaming liquids due to their short contact time and ability to break foam. However, they are also expensive to construct and maintain.
This document discusses mixing theory and equipment used for mixing in the pharmaceutical industry. It begins by defining mixing and classifying mixing into different types including mixing of solids, liquids, and semisolids. It then describes various mechanisms of mixing solids including convective, shear, and diffusion mixing. Key factors that influence mixing of solids like particle properties and interparticle forces are explained. Common equipment for mixing solids in small and large scale are then outlined including tumble blenders, V-cone blenders, double cone blenders, and those with mixing blades. Parameters for effective mixing and evaluating mixing are also summarized.
Size reduction is the process of reducing larger particles into smaller particles using external forces. The key mechanisms of size reduction are cutting, compression, impact, attrition, and a combination of impact and attrition. Different types of mills use these mechanisms, including hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills. Factors like hardness, toughness, stickiness, softening temperature, and moisture content affect how easily a material can undergo size reduction. Laws of Rittinger, Kick, and Bond govern the energy requirements for size reduction.
This document discusses methods for particle size separation and analysis. Size separation involves separating particles of different sizes using sieves, microscopes or sedimentation. Particle size analysis determines the size of particles in a substance or mixture. Sieving is commonly used to separate powder grades by passing materials through sieves of different mesh sizes. Sedimentation analysis particle size based on measuring the settling rate of particles dispersed in a liquid. Both methods are useful for quality control in pharmaceutical production processes.
Freeze drying, also known as lyophilization, uses sublimation to preserve the biological activity of thermolabile materials by removing water at low temperatures under vacuum. The process involves pre-freezing the product, primary drying where ice is sublimated under vacuum, secondary drying to remove residual moisture, and packing under inert gas. Freeze drying results in a dry, porous product that can be stored without refrigeration and reconstituted without loss of quality or activity. It is useful for drying heat-sensitive compounds and materials that require aseptic processing or long shelf life.
This document discusses filtration and clarification processes. It defines key terms like filtration, filter medium, filter cake, and filtrate. It describes how filtration works by restricting solid particle flow while allowing liquid to pass through. Clarification is used when solids are less than 1% and the filtrate is the desired product. Factors that affect filtration rate include surface area, particle size, pore size, resistance, viscosity, temperature, and pressure difference. Common filter media and aids are also outlined. Finally, various filtration equipment like sintered glass filters, filter candles, filter presses, and rotatory filters are described.
The document discusses the angle of repose, which is the maximum slope angle of non-cohesive granular materials before they collapse. It can be measured using methods like the tilting box method, fixed funnel method, and revolving cylinder method. Factors like particle size, moisture content, and measurement method can affect the measured angle of repose. Knowing the angle of repose is important for safely transporting and storing bulk materials.
Size reduction is the process of reducing the particle size of a substance through mechanical means such as grinding or milling. The objectives of size reduction include increasing surface area to improve dissolution, extraction, and absorption. Factors that affect size reduction include material properties like hardness, toughness, stickiness, and softening point. Common size reduction equipment includes hammer mills, which use swinging hammers to crush particles, and roller mills, which pass material between rotating rolls to reduce particle size. The energy required for size reduction depends on theories like Kick's law and Rittinger's law.
The double cone blender is used to homogenously mix dry powders and granules. It has a conical shape at both ends which enables uniform mixing and easy discharge of materials. The blender is made of stainless steel and has safety features like guards and limit switches. It is used in industries like pharmaceutical, food, chemical, and cosmetics to mix products.
The document discusses a hammer mill, which reduces particle size through repeated impacts using rotating hammers. It has various pharmaceutical uses including grinding raw materials and excipients. A hammer mill works by feeding materials into a chamber containing rapid rotating hammers that fracture particles through collisions. Properly sized particles pass through screens while larger ones require further grinding. Key advantages are rapid grinding and easy control of particle size. Disadvantages include potential heat damage and susceptibility to foreign objects in the feed.
This document discusses mixing and homogenization processes. It defines mixing as combining two or more substances together, and identifies perfect mixing as each particle of one material lying adjacent to a particle of the other material. The objectives of mixing are outlined. There are three types of mixtures discussed: positive, negative, and neutral. The mechanisms and equipment used for mixing powders, liquids, and semi-solids are described. Homogenization is defined as preparing a fine emulsion from a coarse one by converting large globules to small globules. Common homogenization equipment like hand homogenizers, Silverson mixers, and colloidal mills are summarized.
This document provides information about mixing in pharmaceutical processes. It defines mixing as a process that combines two or more components so that each particle is in contact with particles of the other ingredients. Ideal mixing occurs when the quantity of materials is the same in all parts of the system. The objectives, types, mechanisms, equipment, and flow patterns involved in liquid and powder mixing are described in detail. Different types of impellers like propellers, turbines, and paddles used for mixing are also explained.
Settling in Suspensions, Formulation of Flocculated and Defloculated Suspens...Suyash Jain
Suspension
Settling in Suspensions,
Stroks law
Theory Of Sedimentation
Formulation of suspensions
Precipitation method:
Dispersion method
Comparision of partical setteling in Defloculated Suspension and Floculated Suspension
Characteristics of an Ideal Suspensions
Formulation of Flocculated and Defloculated Suspensions
Drying is defined as the removal of water or other liquids from a material through the application of heat. It involves three steps: heat transfer to the material, mass transfer of moisture to the surface and evaporation, and transfer of vapor away from the material. There are several theories that describe the drying mechanism, including diffusion, capillarity, and pressure gradient theories. The drying rate curve shows an initial adjustment period, constant rate period, falling rate periods, and an equilibrium moisture content where drying stops. Factors like material properties, air conditions, and particle size influence the drying process and rate.
The document discusses size reduction techniques used in pharmaceutical engineering. It describes the hammer mill and ball mill, which use mechanical forces for size reduction. The hammer mill works by impact between rapidly moving hammers and powder materials, while the ball mill uses impact and attrition between rapidly moving balls inside a rotating cylinder. Both provide descriptions of their basic principles, constructions, operating parameters, advantages and disadvantages.
Mixer Machines Mixer Machines are used in a number of different applications and industries in order to produce a final product that is the result of mixing or combining two or more materials.
Size reduction, or comminution, is the process of reducing substances into smaller pieces or fine powder. It increases the surface area, allowing for faster dissolution and extraction of active constituents. The degree of size reduction depends on factors like the drug's hardness, solvent used, and extraction process. Various size reduction methods include cutting, compression, impact, and attrition. Common mills are the cutter mill, roller mill, hammer mill, ball mill, and fluid energy mill. Levigation involves wet grinding while elutriation separates fine and coarse particles.
Size reduction is the process of reducing the particle size of a substance through mechanical means like grinding or milling. It has several objectives like increasing surface area, improving mixability and compressibility. Factors like hardness, toughness, abrasiveness affect size reduction. Common mechanisms are cutting, compression, impact and attrition. Equipment used include colloid mill, hammer mill, ball mill and jet mill which work on different principles to produce fine particles.
This document discusses mixing theory and equipment used for mixing in the pharmaceutical industry. It begins by defining mixing and classifying mixing into different types including mixing of solids, liquids, and semisolids. It then describes various mechanisms of mixing solids including convective, shear, and diffusion mixing. Key factors that influence mixing of solids like particle properties and interparticle forces are explained. Common equipment for mixing solids in small and large scale are then outlined including tumble blenders, V-cone blenders, double cone blenders, and those with mixing blades. Parameters for effective mixing and evaluating mixing are also summarized.
Size reduction is the process of reducing larger particles into smaller particles using external forces. The key mechanisms of size reduction are cutting, compression, impact, attrition, and a combination of impact and attrition. Different types of mills use these mechanisms, including hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills. Factors like hardness, toughness, stickiness, softening temperature, and moisture content affect how easily a material can undergo size reduction. Laws of Rittinger, Kick, and Bond govern the energy requirements for size reduction.
This document discusses methods for particle size separation and analysis. Size separation involves separating particles of different sizes using sieves, microscopes or sedimentation. Particle size analysis determines the size of particles in a substance or mixture. Sieving is commonly used to separate powder grades by passing materials through sieves of different mesh sizes. Sedimentation analysis particle size based on measuring the settling rate of particles dispersed in a liquid. Both methods are useful for quality control in pharmaceutical production processes.
Freeze drying, also known as lyophilization, uses sublimation to preserve the biological activity of thermolabile materials by removing water at low temperatures under vacuum. The process involves pre-freezing the product, primary drying where ice is sublimated under vacuum, secondary drying to remove residual moisture, and packing under inert gas. Freeze drying results in a dry, porous product that can be stored without refrigeration and reconstituted without loss of quality or activity. It is useful for drying heat-sensitive compounds and materials that require aseptic processing or long shelf life.
This document discusses filtration and clarification processes. It defines key terms like filtration, filter medium, filter cake, and filtrate. It describes how filtration works by restricting solid particle flow while allowing liquid to pass through. Clarification is used when solids are less than 1% and the filtrate is the desired product. Factors that affect filtration rate include surface area, particle size, pore size, resistance, viscosity, temperature, and pressure difference. Common filter media and aids are also outlined. Finally, various filtration equipment like sintered glass filters, filter candles, filter presses, and rotatory filters are described.
The document discusses the angle of repose, which is the maximum slope angle of non-cohesive granular materials before they collapse. It can be measured using methods like the tilting box method, fixed funnel method, and revolving cylinder method. Factors like particle size, moisture content, and measurement method can affect the measured angle of repose. Knowing the angle of repose is important for safely transporting and storing bulk materials.
Size reduction is the process of reducing the particle size of a substance through mechanical means such as grinding or milling. The objectives of size reduction include increasing surface area to improve dissolution, extraction, and absorption. Factors that affect size reduction include material properties like hardness, toughness, stickiness, and softening point. Common size reduction equipment includes hammer mills, which use swinging hammers to crush particles, and roller mills, which pass material between rotating rolls to reduce particle size. The energy required for size reduction depends on theories like Kick's law and Rittinger's law.
The double cone blender is used to homogenously mix dry powders and granules. It has a conical shape at both ends which enables uniform mixing and easy discharge of materials. The blender is made of stainless steel and has safety features like guards and limit switches. It is used in industries like pharmaceutical, food, chemical, and cosmetics to mix products.
The document discusses a hammer mill, which reduces particle size through repeated impacts using rotating hammers. It has various pharmaceutical uses including grinding raw materials and excipients. A hammer mill works by feeding materials into a chamber containing rapid rotating hammers that fracture particles through collisions. Properly sized particles pass through screens while larger ones require further grinding. Key advantages are rapid grinding and easy control of particle size. Disadvantages include potential heat damage and susceptibility to foreign objects in the feed.
This document discusses mixing and homogenization processes. It defines mixing as combining two or more substances together, and identifies perfect mixing as each particle of one material lying adjacent to a particle of the other material. The objectives of mixing are outlined. There are three types of mixtures discussed: positive, negative, and neutral. The mechanisms and equipment used for mixing powders, liquids, and semi-solids are described. Homogenization is defined as preparing a fine emulsion from a coarse one by converting large globules to small globules. Common homogenization equipment like hand homogenizers, Silverson mixers, and colloidal mills are summarized.
This document provides information about mixing in pharmaceutical processes. It defines mixing as a process that combines two or more components so that each particle is in contact with particles of the other ingredients. Ideal mixing occurs when the quantity of materials is the same in all parts of the system. The objectives, types, mechanisms, equipment, and flow patterns involved in liquid and powder mixing are described in detail. Different types of impellers like propellers, turbines, and paddles used for mixing are also explained.
Settling in Suspensions, Formulation of Flocculated and Defloculated Suspens...Suyash Jain
Suspension
Settling in Suspensions,
Stroks law
Theory Of Sedimentation
Formulation of suspensions
Precipitation method:
Dispersion method
Comparision of partical setteling in Defloculated Suspension and Floculated Suspension
Characteristics of an Ideal Suspensions
Formulation of Flocculated and Defloculated Suspensions
Drying is defined as the removal of water or other liquids from a material through the application of heat. It involves three steps: heat transfer to the material, mass transfer of moisture to the surface and evaporation, and transfer of vapor away from the material. There are several theories that describe the drying mechanism, including diffusion, capillarity, and pressure gradient theories. The drying rate curve shows an initial adjustment period, constant rate period, falling rate periods, and an equilibrium moisture content where drying stops. Factors like material properties, air conditions, and particle size influence the drying process and rate.
The document discusses size reduction techniques used in pharmaceutical engineering. It describes the hammer mill and ball mill, which use mechanical forces for size reduction. The hammer mill works by impact between rapidly moving hammers and powder materials, while the ball mill uses impact and attrition between rapidly moving balls inside a rotating cylinder. Both provide descriptions of their basic principles, constructions, operating parameters, advantages and disadvantages.
Mixer Machines Mixer Machines are used in a number of different applications and industries in order to produce a final product that is the result of mixing or combining two or more materials.
Size reduction, or comminution, is the process of reducing substances into smaller pieces or fine powder. It increases the surface area, allowing for faster dissolution and extraction of active constituents. The degree of size reduction depends on factors like the drug's hardness, solvent used, and extraction process. Various size reduction methods include cutting, compression, impact, and attrition. Common mills are the cutter mill, roller mill, hammer mill, ball mill, and fluid energy mill. Levigation involves wet grinding while elutriation separates fine and coarse particles.
Size reduction is the process of reducing the particle size of a substance through mechanical means like grinding or milling. It has several objectives like increasing surface area, improving mixability and compressibility. Factors like hardness, toughness, abrasiveness affect size reduction. Common mechanisms are cutting, compression, impact and attrition. Equipment used include colloid mill, hammer mill, ball mill and jet mill which work on different principles to produce fine particles.
Size reduction is a process of reducing large solid unit masses - vegetables or chemical substances into small unit masses, coarse particles, or fine particles. Size reduction is commonly employed in pharmaceutical industries. The size reduction process is also referred to as Comminution and Grinding.
Generally, size reduction and size separation are combined to obtain powder with the desired particle size distribution (PSD) for acceptable flow and compressibility for downstream processing . The mechanical process of reducing the particle size of a solid is also called milling.
Here's a short way to understand the concept of pharmaceutical engineering . Take a look of this amazing ppt who describes the Chapter -2 of Pharmaceutical engineering i.e. Size Reduction.
Size reduction, process of size reduction, size reduction a topic of pharmac...RajkumarKumawat11
Size reduction, process of size reduction, size reduction a topic of pharmaceutics, cutter mill, roller mill, hammer mill, ball mill, fluid energy mill, the disintegrator, mills used in pharmaceutical process
The document discusses various methods of size reduction or comminution. It describes different types of mills used for size reduction including hammer mill, ball mill, colloid mill, and fluid energy mill. The objectives of size reduction are to reduce particle size, increase surface area, improve handling and flow of powders. Factors affecting size reduction include hardness, toughness, moisture content and specific mills are described such as how a cutter mill uses cutting blades and a ball mill uses grinding balls to reduce particle size.
Size reduction is the process of reducing the particle size of a substance through mechanical means such as cutting, grinding, and milling. This increases the surface area and can improve properties like dissolution rate and bioavailability. In pharmaceutical applications, size reduction allows for more uniform mixing, improved formulations, and sustained drug release. It is carried out manually or using various mills that employ mechanisms like cutting, compression, impact, and attrition. Proper size reduction is important for optimizing drug delivery and bioavailability.
Introduction
Objectives
Methods of size reduction
Advantages of size reduction
Disadvantages of size reduction
Mechanism of size reduction
Laws governing to the size reduction
Principle of Size Reduction, Construction, working and uses of following-
Hammer mill
Ball mill
Fluid Energy Mill
Edge Runner Mill
End Runner Mill
Pharmaceutical pellets are small spherical units prepared by agglomerating fine powders. They range in size from 0.5-1.5mm. Pellets can be used for both oral and injectable drug delivery and offer benefits like taste masking, immediate or sustained release, and delivery of chemically incompatible products in a single dose. Various methods are used to produce pellets including extrusion-spheronization, hot melt extrusion, fluid bed granulation, spray drying, and layering techniques. Pellets can be further processed into tablets, capsules, or other dosage forms and coated to provide modified release of drugs over an extended period.
GRANULATION AND EQUIPMENTS DETAIL BY AMIT KUMARAmitKumar829430
1. The document discusses different types of granulation including wet and dry granulation. Wet granulation involves adding a liquid to a powder mixture to form granules, while dry granulation uses compression without a solvent to form granules.
2. Key advantages of wet granulation are improved flow and compressibility of powders as well as uniform content and drug release. However, it requires more equipment and processing steps than dry granulation.
3. Dry granulation using a roller compactor produces sheets or ribbons of powder material by squeezing between counter-rotating rollers. It has advantages for heat- or moisture-sensitive drugs and provides porous granules for improved tablet properties.
The document discusses pellets, which are small spherical or semi-spherical units used to deliver pharmaceutical ingredients. Pellets offer advantages over other dosage forms like tablets, including flexibility in dosing, the ability to deliver incompatible drugs simultaneously, and different release profiles. The document describes various pelletization techniques like direct pelletizing, powder layering, extrusion-spheronization, and spray drying. It also discusses methods of assessing pellet properties and performance, such as drug content, size distribution, shape, friability, porosity, and in vitro dissolution studies. Pellets can provide controlled release of drugs and offer benefits for dosage form development, drug delivery, and manufacturing.
ASAD REZA INDUSTRIAL TRAINING PRESENTATION (2).pptxMewar University
This presentation summarizes the process of manufacturing tablets. It discusses the key steps which include sieving and mixing the active ingredients and excipients, drying the granules in a fluidized bed dryer, milling to the desired size, blending, compression using tablet presses to form the tablets, coating for properties like taste-masking or controlled release, packaging in blisters or strips with secondary packaging like boxes, and quality control testing of the tablets. The presentation provides an overview of the various unit operations and equipment involved at each stage of tablet manufacturing.
Direct compression is the most advanced technology. It involves only blending and compression. Thus offering advantage particularly in terms of speedy production. Because it requires fewer unit operations, less machinery, reduced number of personnel and considerably less processing time along with increased product stability.
Information about grinder machine according to RSBK.SmitgiriGauswami
Grinders are machines used to reduce substances into coarse particles or fine powder through mechanical force. They are crucial for pharmaceutical processing as particle size directly influences drug performance, dissolution rates, and bioavailability. Uniformly ground particles lead to improved drug dissolution and absorption, ensuring medications are effectively released and absorbed in the body. Grinders contribute to consistent formulation, which is essential for the efficacy and safety of pharmaceuticals.
This presentation gives brief information on pelletization, significance of pelletization. Information also cover on formulation aspects of pellets and different existing methods of production of pellets.
ESR spectroscopy in liquid food and beverages.pptxPRIYANKA PATEL
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...Leonel Morgado
Current descriptions of immersive learning cases are often difficult or impossible to compare. This is due to a myriad of different options on what details to include, which aspects are relevant, and on the descriptive approaches employed. Also, these aspects often combine very specific details with more general guidelines or indicate intents and rationales without clarifying their implementation. In this paper we provide a method to describe immersive learning cases that is structured to enable comparisons, yet flexible enough to allow researchers and practitioners to decide which aspects to include. This method leverages a taxonomy that classifies educational aspects at three levels (uses, practices, and strategies) and then utilizes two frameworks, the Immersive Learning Brain and the Immersion Cube, to enable a structured description and interpretation of immersive learning cases. The method is then demonstrated on a published immersive learning case on training for wind turbine maintenance using virtual reality. Applying the method results in a structured artifact, the Immersive Learning Case Sheet, that tags the case with its proximal uses, practices, and strategies, and refines the free text case description to ensure that matching details are included. This contribution is thus a case description method in support of future comparative research of immersive learning cases. We then discuss how the resulting description and interpretation can be leveraged to change immersion learning cases, by enriching them (considering low-effort changes or additions) or innovating (exploring more challenging avenues of transformation). The method holds significant promise to support better-grounded research in immersive learning.
The technology uses reclaimed CO₂ as the dyeing medium in a closed loop process. When pressurized, CO₂ becomes supercritical (SC-CO₂). In this state CO₂ has a very high solvent power, allowing the dye to dissolve easily.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...Sérgio Sacani
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...Advanced-Concepts-Team
Presentation in the Science Coffee of the Advanced Concepts Team of the European Space Agency on the 07.06.2024.
Speaker: Diego Blas (IFAE/ICREA)
Title: Gravitational wave detection with orbital motion of Moon and artificial
Abstract:
In this talk I will describe some recent ideas to find gravitational waves from supermassive black holes or of primordial origin by studying their secular effect on the orbital motion of the Moon or satellites that are laser ranged.
Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...PsychoTech Services
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdfSelcen Ozturkcan
Ozturkcan, S., Berndt, A., & Angelakis, A. (2024). Mending clothing to support sustainable fashion. Presented at the 31st Annual Conference by the Consortium for International Marketing Research (CIMaR), 10-13 Jun 2024, University of Gävle, Sweden.
The debris of the ‘last major merger’ is dynamically youngSérgio Sacani
The Milky Way’s (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the
‘last major merger.’ Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where the progenitor
collided with the MW proto-disc 8–11 Gyr ago, and the Virgo Radial Merger (VRM), where the progenitor collided with the
MW disc within the last 3 Gyr. These two scenarios make different predictions about observable structure in local phase space,
because the morphology of debris depends on how long it has had to phase mix. The recently identified phase-space folds in Gaia
DR3 have positive caustic velocities, making them fundamentally different than the phase-mixed chevrons found in simulations
at late times. Roughly 20 per cent of the stars in the prograde local stellar halo are associated with the observed caustics. Based
on a simple phase-mixing model, the observed number of caustics are consistent with a merger that occurred 1–2 Gyr ago.
We also compare the observed phase-space distribution to FIRE-2 Latte simulations of GSE-like mergers, using a quantitative
measurement of phase mixing (2D causticality). The observed local phase-space distribution best matches the simulated data
1–2 Gyr after collision, and certainly not later than 3 Gyr. This is further evidence that the progenitor of the ‘last major merger’
did not collide with the MW proto-disc at early times, as is thought for the GSE, but instead collided with the MW disc within
the last few Gyr, consistent with the body of work surrounding the VRM.
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Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
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2. Size Reduction
Content…
Objectives,
Mechanisms & Laws governing size reduction,
factors affecting size reduction,
Principles, construction, working, uses, merits and demerits of
Hammer mill, ball mill, fluid energy mill, Edge runner mill & end runner
mill.
3. Size Reduction
INTRODUCTION:
Size reduction or comminution is the process of reducing drugs
(vegetable and chemical substances) into smaller pieces, coarse particles or
fine powder.
Size reduction is the operation carried out for reducing the size of
bigger particles into smaller one of desired size and shape with the help of
external forces.
COMMINUTION is another term used for size reduction.
Size refers to physical Dimension of an object, whereas Reduction
refers to decrement or the process of decreasing the size.
Size reduction process is also termed as comminution or diminution 'or
pulverisation.
Normally, size reduction may be achieved by two methods, namely
precipitation or mechanical process.
4. Size reduction may be achieved by two methods:
1] Precipitation
2] Mechanical process
In the precipitation method, the substance is dissolved in an appropriate solvent.
Subsequently, it is finely precipitated by the addition of another solvent, which is
miscible with the first, but in the later the substance isinsolu.ble; This method is
suitable for the production of raw materials and bulk drugs.
Inorganic chemicals, such as calcium carbonate, magnesium carbonate and· yellow
mercuric oxide, are prepared by precipitation Method.
In the mechanical process, the substance is subjected to mechanical forces using
grincling equipment (ball mill, roller mill, colloid mill etc.). In general, dry grinding or
milling is used in the production of tablets and capsules, while wet grinding is used in
the preparation of suspensions, emulsions and ointments.
The method of milling is applied either in the production of raw materials or as a
part of the production cycle ·in the manufacture of dosage forms.
5. Pharmaceutical Applications/ Importance of Particle Size Reduction
The process of size reduction is commonly employed in pharmaceutical
industries due to the following reasons:
1. To increase the rate of solution in case of chemical substances, because
reduction of the particle size increases the surface area for the action of
solvent.
2. To allow the rapid penetration of the solvent (menstrum), in case of crude
drugs for the extraction of active constituents from vegetable and animal
drugs.
3. To get a uniform powder because particle size reduction helps in uniform
mixing of drugs, required for preparing different formulations for
administration.
4. To increase the rate of absorption of a drug. The smaller the particle
size, the greater is the rate of absorption.
5. To improve the stability of certain pharmaceutical dosage form, such as
suspensions. The rate of sedimentation decreases to a large extent by
reducing the particle size of the drug.
6. To help in the process of separation of solids from liquids by filtration
or by sedimentation. The rate of filtration or sedimentation depends upon
the particle size.
6. ADVANTAGES OF SIZE REDUCTION
1. Content uniformity:
Mixing of different ingredients can be effective, if the particle size is uniform and
small. Particles of optimum size are desirable for effective mixing.
2. Uniform flow:
Smaller particle size! and controlled size distribution, promote the flow of the. powder
into dies during compression of tablets The same principles are used in the production
of capsules.
3. Effective extraction of drugs:
Smaller particles allow rapid penetration of menstruum or solvent into the tissue or
cells of vegetable and animal origin (liver and pancreas). As a result, extraction or
leaching of active constituent; becomes effective and complete in preparation of
galenicals. The time required for extraction can be shortened.
4. Effective drying:
Drying of a granular mass can be·rapid and effective, if the size of granules is small
and uniform .
5. Improved physical stability:
In case of suspensions and emulsions, the rate of sedimentation decreases to a large
extent if particle size is small.
6. Improved dissolution rate :
Size reduction increases surface area, which facilitates intimate contact of solid
particles and gastric or intestinal juices. Thus, the rate of dissolution enhances.
7. Improved rate of absorption : The smaller the particle size, the faster is the
absorption, because of enhanced dissolution.
7. DISADVANTAGES
1.Drug degradation:
Drug decomposition is possible due to the heat produced,· during milling.
Thermo-labile substances are the most affected. The increased surface
area also facilitates drug decomposition owing to enhanced dissolution.
Cooling support systems are provided to decrease the heat in milling
equipment. Drugs containing waxy materials become soft due to heat
generated during milling. Therefore the feed is chilled before milling.
2. Poor mixing :
Normally, very small particles possess strong cohesive forces, hence,
aggregation of particles is possible. Aggregation inhibits the effective
blending of different additives.
An increase in surface area may promote the adsorption of air, which may
inhibit wettability of the drug during production. Therefore, optimum·
particle size is desirable to improve blending and to avoid poor mixing.
3. Contamination :
During milling and grinding. the grinding surfaces wear off (examples are
ceramic or iron equipment), the particles of which are present as impurities
in the powder. Such type of mills should be avoided, when drugs of high
purity are required.
.
8. Factors Affecting Size Reduction
The following factors affect the process of size reduction:
1. Hardness :
The hardness of the material affects the process of size reduction. It is easier to
break soft material to a small size than hard material.
2. Toughness :
The crude drugs of fibrous nature or those having higher moisture content, are
generally tough in nature.
A soft but tough material may present more problem in size reduction, than a hard
but brittle substance.
3. Stickiness :
Stickiness causes a lot of difficulty in size reduction. This is due to the fact that
material adheres to the grinding surfaces or sieve surface of the mill. It
difficult to powder a drugs of having gummy or resinous nature, if the method used
for size reduction generates heat. Complete dryness of material may help to
overcome this difficulty.
4. Material structure :
Materials which show some special structure may cause problem during size
reduction e.g. vegetable drugs which have cellular structure, generally produce long
fibrous particles on its size reduction. Similarly a mineral substance having lines of
weakness, produces flake like particles on its size reduction.
9. Factors Affecting Size Reduction
5. Moisture content :
The presence of moisture in the material influences a number of its properties such as
hardness, toughness or stickiness which in its turn affects the particle size reduction.
The material should be either dry or wet. It should not be damp. The material having
5% moisture in case of dry grinding and 50% moisture in wet grinding does not
create any problem.
6. Softening temperature :
Waxy substances such as stearic acid or drugs containing oils or fats, become softened
during the size reduction processes, if heat is generated. This can be avoided by
cooling the mill.
7. Purity required :
Various mills used for size reduction often cause the grinding surfaces to wear off and
thus impurities come in the powder. If a high degree of purity is required, such mills
must be avoided. Moreover, the mills should be thoroughly cleansed between batches of
different materials in order to maintain purity.
8.Physiological effect :
Some drugs are very potent. During their particle size reduction in a mill, dust is
produced which may have an effect on the operator. In such cases, the enclosed mills
may be used to avoid dust.
9. Ratio of feed size to product size : To get a fine powder in a mill it is required
that a fairly small feed size should be used. Hence it is necessary to carry out the size
reduction process in several stages, using different equipment e.g. preliminary
crushing followed by coarse powder and then fine grinding.
10. Bulk density : The output of the size reduction of material in a machine, depends
upon the bulk density of the substance.
10. METHODS OF SIZE REDUCTION
The following are the methods of size reduction, in which different mechanisms are
involved:
1. Cutting The material is cut on a small scale by means of a sharp blade, knife root
cutter or any other sharp instrument. On a large scale, a cutter mill is used. Cutting of
drug is usually done to hasten the drying of drugs.
2. Compression: In this method, the material is crushed by the application of pressure.
On a small scale, size reduction is carried out by using pestle and mortar, whereas on a
large scale, roller mill is used.
3. Impact: It occurs when the material is more or less stationary and is hit by an
object moving at high speed or when the moving particle strikes a stationary surface. In
either case, the material breaks into small pieces. There is no apparatus which can be
used on a small scale to affect size reduction by impact. But on a large scale, hammer
mill and disintegrator are used when size reduction of material is done by impact.
4. Attrition
This process involves breaking down of the material by rubbing action between two
surfaces, i.e., surface phenomena. Example is fluid energy ·mill
5. Combined impact and attrition
12. HAMMER MILL
Principle .:
The hammer mill operates on the
principle· of impact between. rapidly
moving hammers mounted on a rotor and·
the powder material.
Construction:
It consists of a stout metal casing,
enclosing a central shaft, to which four
or more swinging hammers are attached.
The lower part of the casing consists of
a screen, through which material can
pass and collected in a suitable receiver,
when the desired degree of size
reduction is reached.
Working :
The material is put into the hopper which
is connected with the drum. These
rotating hammers beat the material to
yield smaller particles The material is
powdered to the desired size, due to
fast rotation of hammers and is collected
under the screen.
13. HAMMER MILL
Uses:
Particle size obtained from 10-400mm.
Also used to mill dry, wet and filter press cakes materials.
Advantage:
It is rapid in action, and is capable of grinding many different types of materials.
They are easy to install and operate, the operation is continuous.
There is little contamination of the product with metal abraded from the mill as no
surface move against each other.
The particle size of the material to be reduced can be easily controlled by changing the
speed of the rotor, hammer type, shape and size of the screen.
Operated in a closed environment dust can. be reduced and explosion hazards can be
prevented.
Disadvantage:
Heat build-up during milling is more, therefore, product degradation is possible.
Hammer mills cannot be employed to mill sticky, fibrous and hard materials.
The screens may get clogged.
Wearing of mill and screen is more with abrasive materials.
14. BALL MILL
These are also known as tumbling mills or
pebble mills.
Principle:
The ball mill works on the principle of impact
between rapidly moving balls
and the powder material enclosed in a hollow
cylinder.
At low speed the balls roll over each other
attrition will be mode of action thus in the
ball mill attrition and impact both
mechanisms takes place.
Construction:
It consists of a hollow cylinder which is
mounted on a metallic frame in such a way
that it can be rotated on its longitudinal axis.
The length of the cylinder is slightly
higher than its diameter.
The cylinder contains balls that occupy 30
to 50% of the mill volume.
The ball size depends on the size of the
feed and the diameter of the mill.
Balls are made up of steel, iron or
stoneware and act as grinding medium.
15. BALLMILL
The drug to be ground is put into the cylinder of
the mill and is rotated. The speed of rotation is
very important.
At a low speed, the mass of balls will slide or roll
over each other and only a negligible amount of size
reduction will occur.
At a high speed, the balls will be thrown out to
the walls by centrifugal force and no grinding will
occur.
The compression by the balls against the wall will
not be sufficient for (effective comminution of the
substance.
At correct speed, the centrifugal force just
occurs, as a result the balls are picked up by the
mill wall and carried nearly to the top, where they
break contact with the wall and fall to the bottom
to be picked up.
In this manner, impact stress will also be induced
and the size reduction is made effective.
Advantages
It can produce very fine powder. Ball mill is used
for both wet and dry grinding processes.
Toxic substances can be ground, as the cylinder is
closed system. Rod or bars can also be used as
grinding media. (example: Sticky material are size
reduced)
In ball mill, installation, operation and labour costs
are low.
Disadvantages
The ball mill is a very noisy machine.
Ball mill is a slow process. Soft, tacky,
fibrous material cannot be milled by ball mill.
Uses:
For fine grinding with a particle size of
100 to 5 mm or less.
For production of ophthalmic and parenteral
products.
For milling dyes, pigments and insecticides
at low speed
16. FLUID ENERGY MILL
Principle:
Fluid energy mill operates on the principle
of impact and attrition. Milling takes
place because of high velocity collisions
between the suspended particles.
Construction:
It consist of an elliptical pipe which has a
height of about 2 meters and diameter
may be ranging from 20 to 200 mm. The
mill surface may be made up of either
soft stainless steel or tough ceramics.
Grinding nozzles are placed tangential and
opposed to the initial flow path of a
powder. Compressed air is used at 600
kilopascals to 1 megapascals. Venturi
feeder is provided in the path of the
airflow. An outlet with a classifier is
fitted to allow the escape of air.
17. FLUID ENERGY MILL
Working:
The air or inert gas is introduced with a very
high pressure through the nozzles. Solids are
introduced into air stream through inlet. Due
to high degree of turbulence, impact and
attritional forces occurs between the
particles. The fine particles are collected
through a classifier. Fluid energy mill reduces
the particles to 1 to 20 micron To get a very
fine powder, even up to five micron, the
material is pre-treated to reduce the
particle size to the order of 100 mesh and
then passed through fluid energy mill.
Uses
The mill is used to grind heat sensitive
material to tine powder. The mill is used to
grind those drugs in which high degree of
purity is required.
Advantages of Fluid Energy Mill
1. The mill is used to grind the material
to fine powder.
2. The particle size of powder can be
controlled due to the use of a classifier.
3. There is no wear of the mill and
hence there is no contamination of the
product.
4. It is useful for grinding heat
sensitive substances such as
sulphonamides, vitamins and antibiotics
18. EDGE RUNNER MILL
Principle:
The size reduction is done by crushing
(Compression) due to heavy weight of stones
and shearing force which is involved during
the movement of these stones.
Construction
It consists of two heavy rollers and a. bed
made of stone or granite. The rollers have a
central shaft and they revolve on its axis.
The rollers are mounted on a horizontal shaft
and move around the bed.
Working:
The material to be ground is put on the bed
and with the help of the scrapers 'it is kept
in the path of the stone wheels. The material
is ground for a definite period and then it is
passed through the sieves to get powder of
the required size.
Uses:
Edge runner mill is used for grinding most of
tough drugs to fine powder.
Disadvantages:
Occupies more space
Contamination of product with roller
is possible
Time consuming process
Not employed for sticky materials
Energy consumption is high.
20. END RUNNER MILL
Principle:
Size reduction is done by crushing
(compression) due to heavy weight of steel
pestle. Shearing stress is also involved
during the movement of mortar and pestle.
Construction:
It is considered as mechanical mortar and
pestle. It consist of steel mortar which is
fixed to Flanged plate. Underneath the
flanged plate, a bevelled cog fitting is
attached to horizontal shaft bearing a pulley.
Hence the plate and mortar can be rotated
with the high speed.
The pestle is dumb bell shaped so that
balancing and efficient grinding by its weight
can be achieved. The bottom of pestle is flat
rather than round. The pestle carries an arm
which is hinged. By this arrangement, the
pestle can be raised from mortar to
facilitate emptying and cleaning. The narrow
central portion of pestle is longer than the
band around it. Hence pestle can rise and fall
over material in the mortar.
Working : The. Material to be
ground placed in mortar .The
scrapper puts the material in the
path of pestle. The mortar revolves
at a high speed . The pestle is placed
in the mortar. The revolving mortar
causes pestle to move. During this
process, size reduction is being
achieved by Shearing as well as
crushing. The material is being
collected and passed through a sieve
to get a the powder of desired size.
Use:
It is suitable for fine grinding.
Disadvantages:
Not suitable for unbroken or slightly
broken condition of drug.
22. THEORIES OF SIZE REDUCTION / MILLING
A number of theories have been proposed to establish a
relationship between energy input and the degree of size
reduction produced.
1. Rittinger’s theory
2. Bond’s theory
3. Kick’s theory
4. Walker’s theory
23. RITTINGER’S THEORY
Rittinger’s theory suggests that energy required in a size reduction
process is proportional to the new surface area produced.
where,
E = energy required for size reduction
KR = Rittinger’s constant
Si = initial specific surface area
Sn = final specific surface area
Application:
It is most applicable in size reducing brittle materials undergoing
fine milling.
24. BOND’S THEORY
Bond’s theory states that the energy used in crack propagation is
proportional to the new crack length produced.
where,
E = energy required for size reduction
KB = Bond’s work index
di = initial diameter of particles
dn = final diameter of particles
Application:
This law is useful in rough mill sizing. The work index is useful in
comparing the efficiency of milling operations.
25. KICK’S THEORY
Kick’s theory states that the energy used in deforming (or
fracturing) a set of particles of equivalent shape is proportional to
the ratio of change of size, or:
where, E = energy required for size reduction
KK = Kick’s constant
di = initial diameter of particles
dn = final diameter of particles
Application:
For crushing of large particles Kick’s theory most useful.
26. WALKER’S THEORY
Walker proposed a generalized differential form of the energy-
size relationship:
where
E = amount of energy (work done) required to produce a change
D = size of unit mass
K = Constant
n = constant
For n =1.0 Walker equation becomes Kick’s theory used for coarse
particles > 1 m.
For n =1.5 Walker equation becomes Bond’s theory. This theory is
used when neither Kick’s nor Rittinger’s law is applicable.
For n =2.0 Walker equation becomes Rittinger’s theory used for
fine particles < 1 m size.