MICROMERITICS Flashcards
1
Q
MICROMERITICS
came from the greek word ____
A
micros
2
Q
MICROMERITICS
micros means
A
small
3
Q
- the science and technology of small particles
- cover particles 100nm to 100mm
A
micromeritics
4
Q
MICROMERITICS
covers particles ____ to ____
A
100nm - 100mm
5
Q
- focuses on particles in the size range of 1nm to ⁓5mm
- has three categories: colloidal dispersions, coarse dispersions, pharmaceutical powders
A
PHARMACEUTICAL MICROMERITICS
6
Q
PHARMACEUTICAL MICROMERITICS
focuses on particles in the size range of ____ to ____
A
1nm to approx 5mm
7
Q
PHARMACEUTICAL MICROMERITICS
3 categories
A
colloidal dispersions (& nanoparticles)
coarse dispersions
pharmaceutical powders
8
Q
PHARMACEUTICAL MICROMERITICS
SIZE:
colloidal dispersions & nanoparticles
A
< 1,000 nm
9
Q
PHARMACEUTICAL MICROMERITICS
SIZE:
coarse dispersions
A
1 - 50um
10
Q
PHARMACEUTICAL MICROMERITICS
SIZE:
pharmaceutical powders
A
50um
11
Q
PHARMACEUTICAL MICROMERITICS
the only dispersion not covered
A
molecular dispersion
12
Q
how many micromeritic properties
A
7
13
Q
MICROMERITIC PROPERTIES
ANALYTICAL TECHNIQUE:
* laser diffraction
* dynamic light scattering
REOPRTED PARAMETER:
* D-value
A
SIZE
14
Q
MICROMERITIC PROPERTIES
ANALYTICAL TECHNIQUE:
* imaging
* scanning electron microscopy
REPORTED PARAMETER:
* high-resolution images
* circularity
A
SHAPE
15
Q
MICROMERITIC PROPERTIES
ANALYTICAL TECHNIQUE:
* electrophoretic light scattering
REPORTED PARAMETER:
* zeta potential
A
CHARGE
16
Q
MICROMERITIC PROPERTIES
ANALYTICAL TECHNIQUE:
* atomic force microscopy
* rheometry
REPORTED PARAMETER:
* elasticity
* stiffness (Young’s modulus)
A
MECHANICAL
17
Q
A
18
Q
MICROMERITIC PROPERTIES
ANALYTICAL TECHNIQUE:
* gas adsorption method
REPORTED PARAMETER:
* surface area
* pore size
A
SURFACE
19
Q
MICROMERITIC PROPERTIES
ANALYTICAL TECHNIQUE:
* differential sanning calorimetry
REPORTED PARAMETER:
* percentage of crystallinity
A
INTERNAL MICROSTRUCTURE
20
Q
MICROMERITIC PROPERTIES
ANALYTICAL TECHNIQUE:
* bulk density
* tapped density
REPORTED PARAMETER:
* hausner ratio
A
FLOWABILITY & COHESIVENESS
20
Q
- shape, surface area of each paritcle, size range and number, weight and volume must be considered
- cannot be describe by a single dimension
A
PARTICLE SIZE
21
Q
particles cannot be described by a ____
A
single dimension
22
Q
PARTICLE SIZE
a size of a spherical particle is characterized by its ____
A
diameter
22
Q
PARTICLE SIZE
a size of a non-spherical particle is characterized by its ____
A
equivalent spherical diameter
22
# **PARTICLE SIZE | EQUIVALENT SPHERICAL DIAMETER**
* the diameter of a circle that has the **same projected area** as the particle
* **imaginary circle** that covers 2 points of the particle
PORJECTED
22
# **PARTICLE SIZE**
**absence** of **measurable diameter** with **irregularly shaped** particles
equivalent spherical diameter
22
# **PARTICLE SIZE**
* for **non-spherical**/**asymmetrical** particles
* **approximate** particle size **based** on **diameter of sphere**
equivalent spherical diameter
23
# **PARTICLE SIZE | EQUIVALENT SPHERICAL DIAMETER**
* the diameter of the particle at the point that **divides a randomly oriented particle** into **two equal projected areas**
MARTIN'S
24
# **PARTICLE SIZE | EQUIVALENT SPHERICAL DIAMETER**
**commonly used** in particle sizing
MARTIN'S
FERET'S
24
# **PARTICLE SIZE | EQUIVALENT SPHERICAL DIAMETER**
**not used** in particle sizing because of **variations**
PROJECTED
24
# **PARTICLE SIZE | EQUIVALENT SPHERICAL DIAMETER**
* the **distance** between imaginary **parallel lines tangent to a radomly oriented particle** and **perpendicular to the ocular scale**
FERET'S
25
* **represents** the **number of particles** in each size present in a given sample
* **represented** as **frequency curve** or **cumulative percentage** over/under a particular size curve
* particles in a group could either be: **monodisperse**, **polydisperse**
PARTICLE SIZE DISTRIBUTION
25
# **PARTICLE SIZE DISTRIBUTION**
collection of particles of **uniform size**
MONODISPERSE
26
# **PARTICLE SIZE DISTRIBUTION**
collection of particles of **more than one size**
POLYDISPERSE
26
# **PARTICLE SIZE DISTRIBUTION**
is represented as ____ or ____ over/under a particular size curve
frequency curve or cumulative percentage
26
# **METHODS OF DETERMINING PARTICLE SIZE DISTRIBUTION**
number of particles
optical microscopy
electron microscopy
26
# **METHODS OF DETERMINING PARTICLE SIZE DISTRIBUTION**
weight of particles
sieving
sedimentation
centrifugation
27
# **METHODS OF DETERMINING PARTICLE SIZE DISTRIBUTION**
light scattering by particles
photon correlation spectroscopy
27
# **METHODS OF DETERMINING PARTICLE SIZE DISTRIBUTION**
volume of particles
coulter counter method
28
**particle shape analysis** is carried out using ____
imaging techniques
28
it affects:
* **solubility**
* **packing** properties
* **flowability**
* **bulk powder** properties
* **surface area**
PARTICLE SHAPE
28
carried out using **imaging techniques**
PARTICLE SHAPE ANALYSIS
29
# **PARTICLE SHAPE**
measure of deviation from **roundness**;
* *if **AR = 1**, the particle is a **perfect sphere***
ASPECT RATIO
29
# **PARTICLE SHAPE**
expresses the **radius** of **cuvature** of the particle **corners**
* *if **roundness = 1**, the particle is **circular***
| (roundness of corners)
ROUNDNESS
30
# **PARTICLE SHAPE**
measures the **closeness** to a **perfect sphere**
* *if **sphericity = 1**, the particle is **sphere***
| (roundess as a whole)
SPHERICITY
30
# **PARTICLE SHAPE**
representative of **local surface textures** between corners
* *if **roughness decreases**, the particle surface has **more concavities***
ROUGHNESS
31
# **SURFACE AREA & SPECIFIC SURFACE**
what is the **relationship** between the **asymmetry** of the particle to the **specific surface**
DIRECTLY PROPORTIONAL
31
defined as the **surface area per unit volume** or **per unit weight**
SPECIFIC SURFACE
32
# **SURFACE AREA & SPECIFIC SURFACE**
what is the **relationship** of the **particle size** to the **surface area**
inversley proportional
33
materials with **high specific area** may have cracks and ____ that **adsorb gases** & **vapors** into their **interstices**
PORES
33
a measure of the **air spaces** or **voids** in a material (ɛ)
POROSITY
33
describes the **behavior** of a material **under load**
* elasticity
* stiffness
* rigidity
* hardness
* strength
MECHANICAL PROPERTIES
34
# **MECHANICAL PROPERTIES**
**extent of resistance** to deformation (**shear modulus**, **G**)
STIFFNESS
35
# **MECHANICAL PROPERTIES**
**resist deformation** when exposed to stress and **return** to its **original state** (**Young's modulus**, **Eγ**)
ELASTICITY
36
* the **surface charge** on a particle **has a potential** to **affect** its **interaction** with other particle
* **zeta potential** (electrokinetic potential)
* **formation** of the **electrical double layer**
ELECTRICAL PROPERTIES
36
# **ELECTRICAL PROPERTIES**
DIFFUSE LAYER:
ions are diffused **more freely** ____
around the particle
36
# **ELECTRICAL PROPERTIES**
**hydrodynamic plane of shear** is also called
slipping plane
37
# **ELECTRICAL PROPERTIES**
HYDRODYNAMIC PLANE OF SHEAR:
**charges beyond** the slipping plane will ____ with the particle as an entity.
NOT MOVE
37
# **ELECTRICAL PROPERTIES**
HYDRODYNAMIC PLANE OF SHEAR:
**ions within** this boundary will ____ with particle as **one entity**
MOVE
37
# **ELECTRICAL PROPERTIES**
STERN LAYER:
the particle will **attract ions** of the ____ charge
OPPOSITE
38
# **ELECTRICAL PROPERTIES**
STERN LAYER:
**positive** ions will ____ to the **surface**. these ions are **tightly bound immediately around** the surface
MOVE CLOSER
38
* the **choice of sutiable sizing technique** for measuring PSD **depends** on the **expected size range** of the particle
* has **three** categories:
- **single particle counting**
- **fractionation**
- **ensemble averaging**
PARTICLE SIZING TECHNIQUES
38
# **PARTICLE SIZING TECHNIQUES**
the **choice of sutiable sizing technique** for measuring PSD **depends** on the ____ of the particle
expected size range
39
means to **verify** and **supplement** the **information gained** from the **first** technique with a **complemenetary second** and possibly a t**hird technique** that used **different mechanism** to measure particle size
ORTHOGONAL
40
* used to **confirm measurements** made by an **unrelated** method
* confirmation of an initial test with a **different** method
ORTHOGONAL MEASUREMENTS
40
# **IMAGING ANALYSIS**
* **direct** measurement of **microstructural** features and **intermolecular** forces at **nanoscale** level
* **high resolution**, **atomic-resolution** method -- **topographical image**
ATOMIC FORCE MICROSCOPY
40
# **IMAGING ANALYSIS**
provides measurements on **surface textures**
TOPOGRAPHICAL IMAGE
40
# **IMAGING ANALYSIS**
* high resolution direct technique for **characterizing particles** from about **1 microns to several mm**
* typically used in **conjunction with ensemble-based particle sizing method** such as **laser diffraction**
AUTOMATED STATIC & DYNAMIC IMAGE ANALYSIS
41
# **IMAGING ANALYSIS**
**Automated Static & Dynamic Image Analysis** is typically used in **conjunction with ensemble-based particle sizing method** such as ____
LASER DIFFRACTION
42
# **IMAGING ANALYSIS | AUTOMATED STATIC & DYNAMIC IMAGE ANALYSIS**
* uses microscope to capture image of the **stationary particles**
* **size** and **shape** measurements
STATIC
42
# **IMAGING ANALYSIS | AUTOMATED STATIC & DYNAMIC IMAGE ANALYSIS**
* uses microscope to capture image of **particles flowing**
* ideal for **bulk solids**
DYNAMIC
43
# **IMAGING ANALYSIS | AUTOMATED STATIC & DYNAMIC IMAGE ANALYSIS**
**dynamic** image analysis is ideal for ____
bulk solids
43
* **photon correlation spectroscopy** (PCS); **quasi-electric light scattering** (QELS)
* measures particle size in the submicron range **below 1nm**
* measurement with **light-scattering of dynamic**
DYNAMIC LIGHT SCATTERING
44
* **small amount** of sample is required
* analysis is **rapid**
* does **not** require **highly specialized personnel**
* **noninvasive**
DYNAMIC LIGHT SCATTERING
44
an **ensemble technique** - the **diameter** obtained is that of a sphere that has **translational diffusion coefficient** as the particle being measured
***(means that size is larger than what is measured in EM)***
DYNAMIC LIGHT SCATTERING
45
* used for particles ranging from **hundreds of nanometers** up to **several millimeters**
* measured PSD by measuring the **angular variation** in the **intensity of light scattered** as a ***laser beam*** passes through a **dispersed particle sample**
LASER DIFFRACTION
45
# **LASER DIFFRACTION**
what is the **relationship** between **particle size** and the **angle of diffraction**
DIRECTLY PROPORTIONAL
46
* one of the **oldest** method; **method of choice** for **coarser powders**
* this method utilizes a **series of standard sieves stacked over one another** then subjected to standardized period of **agitation** and the weight retaned on eahc sieve is accurately determined
SIEVING
46
# **SIEVEING**
it is a **method of choice** for what type of **powders**
COARSER POWDERS
46
# **METHODS FOR DETERMINING SURFACE AREA**
can be **computed** from ____ obtained
PSD
47
* the **amount** of **gas** or **liquid solute** that is **adsorbed** onto the **powder** to **form monolayer**
* depends on the **rate** at which **gas** or **liquid** **permeates a bed of powder**
METHODS FOR DETERMINING SURFACE AREA
48
# **METHODS FOR DETERMINING SURFACE AREA**
* **amount** of a **gas** or **liquid** solute that is **adsorbed** onto the sample of powder to **form a monolayer** is a **direct function** of the **surface area** of the sample
ADOSORPTION METHOD
48
# **METHODS FOR DETERMINING SURFACE AREA | ADSOPRTION METHOD**
**insturment** used to calculate **surface area** and **pore structure**
QUANTASORB
48
# **METHODS FOR DETERMINING SURFACE AREA | ADSORPTION METHOD**
what is the **relationship** between the **amount of quantasorb** and the **surface area**
directly proportional
49
# **METHODS FOR DETERMINING SURFACE AREA**
* the rate at which a gas or liquid **permeates a bed of powder** is related to the **surface area exposed to the permeant**
AIR PERMEABILITY METHOD
50
# **METHODS FOR DETERMINING SURFACE AREA | AIR PERMEABILITY METHOD**
**instrument** used to calculate **surface area** and **pore structure**
FISHER SUBSIEVE SIZER
50
**FUNDAMENTAL** properties of powders
particle size distribution
surface area
51
powders may be:
* **free-flowing**
* **cohesive**/**sticky**
FLOW PROPERTIES & FLOWABILITY
51
# **FLOW PROPERTIES & FLOWABILITY**
* characterized by **dustibility**
* example: **lycopodium** - 100% dustibility
FREE-FLOWING
52
# **FLOW PROPERTIES & FLOWABILITY**
**Free-flowing** is characterized by
DUSTIBILITY
53
# **FLOW PROPERTIES & FLOWABILITY**
dustibility of **lycopodium**
100%
54
* the **maximum angle possible** between the surface of a pile of powder and the horizontal plane
***the lower the θ, the bettwer the flow***
ANGLE OF REPOSE
54
# **ANGLE OF REPOSE**
what is the **relationship** of the **angle of repose** to the **flowability** of the sample
directly proportional
54
# **ANGLE OF REPOSE**
the **lower** the θ, the ____ the flow
better
54
# **ANGLE OF REPOSE**
θ
theta in degree
55
* the granular materials are **poured from a funnel** at a certain height onto a selected base with **known roughness properties**
* the funnel is either **fixed** or **raised slowly** while the **conical chape** of the material heap **is** **forming** to **minimize the effect of the falling particles**
FIXE FUNNEL METHOD
55
# **PORE SIZE & POROSITY (VOIDS OR SPACES)**
what do you call the **voids** in between **powder particles**
INTERPARTICULATE VOIDS
56
# **PORE SIZE & POROSITY (VOIDS OR SPACES)**
the voids **within** a **specific** particle
INTRAPARTICULATE VOIDS
57
# **DESNITIES OF PARTICLES**
density of material itself is **exclusive** of inter- and intraparticular voids
TRUE DENSITY
58
# **DESNITIES OF PARTICLES**
density of material itself **including intraparticular** voids
GRANULAR DENSITY
58
# **DESNITIES OF PARTICLES**
density of material itself **inclusive** of inter- and intraparticular voids
BULK DENSITY
58
# **DESNITIES OF PARTICLES**
* aka **compressed bulk density**
* obtained after compacting by **tapping** or **vibration**
TAPPED DENSITY
59
# **DESNITIES OF PARTICLES**
**tapped** density is also called
compressed bulk density
59
# **DETERMINATION OF BULK DENSITY**
Method I
graduated cylinder
60
# **DETERMINATION OF BULK DENSITY**
Method II
SCOTT VOLUMETER
61
# **DETERMINATION OF BULK DENSITY**
ρ
rho
61
# **DETERMINATION OF BULK DENSITY**
what is the **relationship** between the **bulk** density and the **inter**particulate voids
directly proportional
61
# **DETERMINATION OF BULK DENSITY**
what is the **relationship** between the **tapped** density and the **inter**particulate voids
inversely proportional
61
**mechanical tapping** is achieved by raising the cylinder and allowing it to drop under its own weight
DETERMINATION OF TAPPED DENSITY
62
# **DETERMINATION OF TAPPED DENSITY**
is achieved by **raising the cylinder** and **allowing it to drop under its own weight**
MECHANICAL TAPPING
62
**Carr** reported that the **more a material is compacted** in a compaction or tap bulk density test, the **poorer are its flow properties**
COMPRESSIBILITY (CARR'S) INDEX
63
# **COMPRESSIBILITY (CARR'S) INDEX**
**who** reported that the **more a material is compacted** in a compaction or tap bulk density test, the **poorer are its flow properties**
Carr
64
# **COMPRESSIBILITY (CARR'S) INDEX**
what is the **relationship** between the **compressibility index** and the **flow property**
directly proprotional
64
* a set of particles can be **filled into a volume of space** to produce a **powder bed**, which is in **static equilibrium** owing to the **interaction** of **gravitational** and **adhesive/cohesive forces**
* by **slight vibration** of the bed, particles can be **mobilized** and at **static equilibrium**, they occupy a **different spatial voume** than before
PACKING GEOMETRY
64
# **PACKING GEOMETRY**
a set of particles can be **filled into a volume of space** to produce a ____, which is in **static equilibrium** owing to the **interaction** of **gravitational** and **adhesive/cohesive forces**
powder bed
64
# **PACKING GEOMETRY**
a set of particles can be **filled into a volume of space** to produce a **powder bed**, which is in ____ owing to the **interaction** of **gravitational** and **adhesive/cohesive forces**
STATIC EQUILIBRIUM
65
# **PACKING GEOMETRY**
a set of particles can be **filled into a volume of space** to produce a **powder bed**, which is in **static equilibrium** owing to the **interaction** of ____ and ____ forces
GRAVITATIONAL & ADHESIVE/COHESIVE FORCES
66
# **PACKING GEOMETRY**
by ____ of the bed, particles can be **mobilized** and at **static equilibrium**, they occupy a **different spatial voume** than before
SLIGHT VIBRATION
66
# **PACKING GEOMETRY**
by **slight vibration** of the bed, particles can be ____
MOBILIZED
67
# **PACKING GEOMETRY**
at ____, they occupy a **different spatial voume** than before
STATIC EQUILIBRIUM
67
# **PACKING GEOMETRY**
**static equilibrium**, they occupy a ____ than before
DIFFERENT SPATIAL VOLUME
68
# **PACKING GEOMETRY**
* **loosest** packing
* porosity = **48%**
CUBIC
68
# **PACKING GEOMETRY**
POROSITY:
**cubic**
48%
69
# **PACKING GEOMETRY**
* **closest** packing
* porosity = **26%**
RHOMBOHEDRAL
70
# **PACKING GEOMETRY**
POROSITY:
**rhombohedral**
26%
