What is a quasi steady flow?
A flow is said to be quasi steady if temporal variations at a spatial location are much smaller (they would be zero if the flow was steady) ompared to spatial variations for any quantity.
What happens in a quasi steady state specific growth?
In a quasi-steady state the specific growth rate gradually decreases. A unique feature of a fed batch culture is that it allows continuous reproduction of the transient conditions between two specific growth rates, which can be chosen at will.
What is pseudo steady state assumption?
Pseudo Steady State Hypothesis (PSSH)
The PSSH assumes that the net rate of species A* (in this case, NO3*) is zero. Solving for NO3* This result shows why the rate decreases as temperature increases.
What is steady state condition in physics?
Definition of steady state
: a state or condition of a system or process (such as one of the energy states of an atom) that does not change in time broadly : a condition that changes only negligibly over a specified time.
What is quasi steady state in bioprocess?
A fed batch culture may reach a “quasi-steady state” in which the specific. growth rate (ph- ‘) virtually = the dilution rate, that is, the ratio of medium flow. rate to culture volume. In a quasi-steady state the specific growth rate gradually. decreases.
What is quasi stationary state?
“Quasi-stationary” states are approximately time-independent out of equilibrium states which have been observed in a variety of systems of particles interacting by long-range interactions.
What is the condition for a quasi steady state Mcq?
What is the condition for a Quasi-Steady state? Explanation: Although the total biomass in the culture increases with time, cell concentration(x) remains virtually constant, that is (dx/dt) = 0 and therefore µ = D (approx.). This situation is termed as a Quasi-Steady State.
What are the three assumptions of the steady state?
There are several assumptions when working with steady state flow. First, the mass flow throughout the systems is constant. Second, the fluid maintains a consistent composition. Third, the only interaction between the surroundings and the system is heat and work.
Why have a steady state condition?
A steady state flow process requires conditions at all points in an apparatus remain constant as time changes. There must be no accumulation of mass or energy over the time period of interest. The same mass flow rate will remain constant in the flow path through each element of the system.
What is a quasi stable state and what is a steady state?
Both the states of an astable multivibrator are quasi-stable. Basically,Quasi stable multivibrators stands for monostable multivibrators will have one stable (proabably in zero state) and it will go to logic high when it is triggered by external trigger and it will stay there for value determined by time constant(.
What do you mean by quasi steady state Mcq?
Explanation: The total biomass in the culture (X) increases with time, cell concentration (x) remains virtually constant, that is dx/dt ≅ 0 and therefore μ ≅ D. This situation is termed as a quasi steady state.
What is quasi steady state heat transfer?
The quasi-steady distribution of temperature occurs in the wall of the component after heating the component for a long period of time at a constant rate. The quasi-steady state can be characterized by the following factors: Constant temperature difference between the selected points of the component (Fig. 1)
What remains constant during a steady flow process Mcq?
Steady flow process is a process where the fluid properties do not change with time. A steady-flow process is characterized by the following: No properties within the control volume change with time. That is mcv = constant; Ecv = constant.
What is batch and fed-batch fermentation?
Batch, where no extra feeding is used from beginning to end of the process. Fed-batch, where feeding with substrate and supplements can extend the duration of culture for higher cell densities or switch metabolism to produce e.g. a recombinant protein.
What is the difference between steady state and pseudo steady state?
Pseudo-steady state (or pseudo steady-state), is also referred to as “stabilized,” or as “steady state in a bounded drainage area.” This type of reservoir flow occurs much more frequently than steady-state flow or unsteady-state flow with an expanding drainage radius.
What are the conditions for steady flow process?
When a flow process is satisfying the following conditions, it is known as a steady flow process.
- The mass and energy content of the control volume remains constant with time.
- The state and energy of the fluid at inlet, at the exit and at every point within the control volume are time independent.
What is an example of steady state?
An example of steady state can be found a bathtub with the drain open and water being added. If water is leaving the tub at the same rate that water is being added, the state variable volume will be constant over time.
How many quasi stable states are there in astable multivibrator?
two quasi-stable states
The basic difference among the types of multivibrator is the number of stable states associated with each type. The bistable has two stable states, the monostable has one stable state (and one quasi-stable state), and the astable has no stable states (two quasi-stable states).
What is the condition for a quasi-steady state Mcq?
What is quasi-steady state in bioprocess?
Can a closed system be steady state?
No, a closed system is permeable to energy and therefore, closed system cannot produce a state of thermodynamic equilibrium.
Is velocity constant in steady flow?
In steady flow, the velocity vector at any point is constant.
Why is fed-batch better than batch?
A fed-batch culture is more productive, yields better with controlled sequential additions of nutrients, enables higher cell densities, and prolongs product synthesis.
Why we use fed-batch?
Fed-batch processes. One way of keeping nutrients from becoming a limiting factor is to constantly supply them during cultivation. This is called a fed-batch process, which is a partly open system. The advantage of feeding during cultivation is that it allows to overall achieve higher product quantities overall.
What is the difference between steady state and pre steady state?
Although both methods are used to solve for a rate of reaction, they are used under different conditions. The steady state method can only be used if the first step of a reaction is much slower than the second step, whereas the pre-equilibrium approximation requires the first step to be faster.