Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharm Manufacturing > Mixing (Blending) > Flashcards

Mixing (Blending) Flashcards

1
Q

a process in which two or more ingredients in separate or roughly mixed conditions are treated so that each particle of any one ingredient is as nearly as possible adjacent to a particle of each of the other ingredients

A

Mixing (Blending)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

This is usually accomplished utilizing paddles, revolving blades, or other devices within the mixer, arranged to move adjacent volumes of the fluid in different directions, thereby shuffling the system in three dimensions

A

Bulk transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

• velocity differences within the body of fluid produce randomization of the fluid molecules. For this reason, turbulence is a highly effective mechanism of mixing.

A

Turbulent mixing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

highly viscous fluids are being processed.

A

Laminar mixing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Just read

A

When two different liquids are mixed through laminar flow, the generated shear stretches the interface between them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The primary mechanism responsible for mixing at the molecular level is ____ resulting from the thermal motion of the molecules.

A

diffusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When it occurs in conjunction with laminar flow __ tends to reduce the sharp discontinuities at the interface between the fluid layers and, if allowed to proceed for sufficient time, results in complete mixing

A

Molecular diffusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

A system for liquid mixing commonly consists of two primary components:

A
  1. a tank or other container suitable for holding the material being mixed
  2. means supplying energy to the system to facilitate reasonably rapid mixing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The distinction between impeller types is often made based on

A
  1. type of flow pattern they produce
  2. the blades’ shape and pitch
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

In impellers the flow pattern may be analyzed in terms of three components:

A

radial, axial or longitudinal, tangential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

perpendicular to the impeller shaft

A

radial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

parallel to the impeller shaft

A

axial or longitudinal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

tangential to the circle of rotation around the impeller shaft

A

tangential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
  • the segment of a multithreaded screw
  • either right- or left-handed depending on the direction of slant of their blades
A

Propellers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

• The three-blade design is most commonly used with fluids
• most efficient when they run at high speeds in liquids of relatively low viscosity

A

Propellers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

the primary effect of a propeller is due to a __.

A

axial flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

With these types of impellers, a radial flow is induced by the centrifugal action of the revolving blades

A

Turbines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

When radial-tangential flow is desired, turbines with blades set at a 90-degree angle to their shaft are employed

A

Turbines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

can be operated satisfactorily in fluids 1000 times more viscous than fluids in which a propeller of comparable size can be used

A

Turbines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

generally operated at low speeds of 50 rpm or less

A

Paddles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Their blades have a large surface area as compared to the tank in which they are employed, a feature that permits them to pass close to the tank walls and effectively mix viscous liquids and semisolids

A

Paddles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

• involve sub-surface jets of air, or less commonly of some other gas, for adequate mixing of certain liquids
• The jets are usually arranged so that the buoyancy of the bubbles lifts liquids from the bottom to the top of the mixing vessel
• the intense turbulence generated by the jet produces intimate mixing

A

Air jets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

They utilize liquids pumped at high pressure into a tank for mixing

A

Fluid jets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

the fluids are pumped through nozzles arranged to permit a good circulation of material throughout the tank

A

Fluid jets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

produces an uninterrupted supply of freshly mixed material and is often desirable when huge volumes of materials are to be handled.

A

Continuous mixing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

CONTINUOUS OR IN-LINE MIXERS can be accomplished in two ways

A
  1. tube or pipe
  2. mixing chamber
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

CONTINUOUS OR IN-LINE MIXERS way in which the material flows and in which there is very little backflow or recirculation

A

tube or pipe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

CONTINUOUS OR IN-LINE MIXERS way in which a considerable amount of holdup and recirculation occurs

A

mixing chamber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Semi-solid mixing mechanism

A
  1. Powder state
  2. Pellet state
  3. Plastic state
  4. Sticky state
  5. Liquid state
30
Q

the initial powder (starting material)

A

powder state

31
Q

when the amount of liquid is added to the powder→ coarse granules

A

pellet state

32
Q

granular appearance is lost; becomes homogenous

A

Plastic state

33
Q

paste-like appearance due to continual incorporation of liquid

A

Sticky state

34
Q

Further addition of liquid decreases consistency until fluid State is reached

A

Liquid state

35
Q

Has counter-rotating blades or heavy arms that work the plastic mass.

A

Sigma-Blade mixer

36
Q

Sigma-Blade mixer- The blades rotate tangentially with a speed ratio of about ____.

A

2:1

37
Q

The mixing element rotates around the circumference of the mixer’s container while simultaneously rotating about its axis

A

Planetary mixer

38
Q

Planetary mixer just read

A

The double rotation of the mixing element and its offset position reduces the dead zones and avoids vortex formation

39
Q

Provide forces that incorporate kneading, shearing, smearing, and blending of materials for total uniform consistency

A

Mulling Mixers

40
Q

This process produces enough pressure to move, intermingle and push particles into place without crushing, grinding, or distorting the ingredients

A

Mulling Mixers

41
Q

The result of this mixer is a truly uniform
consistency in both physical and chemical structure

A

Mulling mixers

42
Q

2 mils

A

Roller mills
Colloid mills

43
Q

Consist of one or more rollers and are commonly used.

A

Roller mills

44
Q

the three-roller mills types that are preferred are…

A

Apron roll
Center roll
Feed roll

45
Q

consists of a high-speed rotor (3,000 to 20,000 rpm) and a stator with conical milling surfaces between which an adjustable clearance ranging from 0.002 to 0.03 inches is present

A

Colloid mill

46
Q

Solid mixing (Mixing mechanisms 3)

A
  1. Convective Mixing
  2. Shear Mixing
  3. Diffusive mixing
47
Q

can occur by an inversion of the powder bed, by means of blades, paddles, a revolving screw, or by any other method of moving a relatively large mass of material from one part of the powder
bed to another

A

convective mixing

48
Q

the fastest and most efficient mixing mechanism

A

convective mixing

49
Q

When shear occurs between regions of different composition and parallel to their interface, it reduces the scale of segregation by thinning the dissimilar layers

A

Shear Mixing

50
Q

Large or irregular grains of powder tend to be expelled from regions of high shear through a mechanism known

A

shear-induced migration

51
Q

is the rate-limiting mechanism for mixing

A

Diffusion

52
Q

consists of a container of the one of several geometric forms, which is mounted so that it can be rotated about an axis to cause movement of the material in all planes, which is necessary for rapid overall mixing.

A

Tumblers/Blenders-A tumbling mixer

53
Q

employ a stationary container to hold the material and bring about mixing by means of moving screws, paddles, or blades

A

Agitators mixers

54
Q

employ a stationary container to hold the material and bring about mixing by means of moving screws, paddles, or blades

A

Agitators mixers

55
Q

It consists of a horizontal cylindrical tank usually opening at the top and fitted with helical blades or ribbons

A

Ribbon Mixer/Blender

56
Q

The blades are mounted on the horizontal axle by struts, and are rotated to circulate the material to be mixed.

A

Ribbon Mixer/Blender

57
Q

The helical blades are wound (in most cases) in the opposite directions to provide for the movement of material in both directions along the axis of the tank

A

Ribbon Mixer/Blender

58
Q

also used for solid-solid blending although mostly in a step prior to the introduction of liquids

A

Planetary Mixers

59
Q

A screw assembly is mounted in a conical chamber, with the screw moving in a planetary motion, and also lifting the powder to be blended from the bottom to the top

A

Nauta mixers

60
Q

It is a modification of the vertical impeller.

A

Fluidized Air Mixer

61
Q

The impeller is replaced by a rapidly moving stream of air fed into the bottom of the shell. The body of powder is fluidized, and mixing is accomplished by circulation and over tumbling in the bed

A

Fluidized Air Mixer

62
Q

can accomplish both dry mixing and wet granulation efficiently, and in lesser time

A

Processors or Rapid Mixer-Granulator

63
Q

was one of the first high-shear powder blenders capable of rapidly blending pharmaceutical powders and wet massing within the same equipment

A

Lödige Mixer

64
Q

It is another type of high-speed powder mixer and processor. The mixer utilizes a bowl mounted in the vertical position, a highspeed mixer blade that revolves around the bottom of the bowl and a high-speed chopper blade, which functions as a lump and agglomerate breaker

A

Diosna Mixer-Granulator

65
Q

modification of the industrial planetary mixers

A

Gral Mixer-Granulator

66
Q

Provides composition uniformity especially in manufacturing tablets and capsules

A

Continuous Mixers

67
Q

It consists of a series of fixed, flow-twisting or flow-splitting elements designed for blending of free-flowing solids

A

Blendex

68
Q

provides efficient mixing for a variety of solids without heat generation or particle size reduction

A

Blendex

69
Q

• material is mixed under tumbling motion
• provides intense mixing of ingredients

A

Barrel Type Continuous Mixer

70
Q

consists of several “V”-shaped blenders connected in series

A

Zig-zag Continuous Blender

71
Q

When the blender is inverted, the material splits into two portions, one-half of the material moves backwards, while the other moves forward

A

Zig-zag Continuous Blender

Pharm Manufacturing (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions