Winter 2003

Chemical Engineering 518

K. A. Solen

 

Biomedical Engineering Principles

 

 

Reading and Homework Assignments

 

 

Class

Date

Topic

Reading Due

 

Homework

 

 

 

 

Set No.

Problems Due

1

M 1/6

Introduction

---

---

---

2

W 1/8

Body Material Balances

Chapters 1 and 2#

---

---

3

F 1/10

Blood Properties/Rheology

pp. 37-54#

1

2.1@,2.3@,2.5@

4

M 1/13

Blood Properties/Rheology

pp. 54-64#

2

3.1,3.2,SP2

5

W 1/15

Circulatory Dynamics

pp. 69-89#

3

3.4,3.7@,SP3,LR1

6

F 1/17

Neuroprosthetics

---

4

4.1@,4.2@,4.3@,SP4

 

M 1/20

Holiday (Martin Luther King Day)

 

 

 

7

W 1/22

*Heat Generation/Losses

pp.93-124#

---

LR2

8

F 1/24

Body Heat Exchange

pp.124-141#

5

5.2,5.3@

9

M 1/27

Body Heat Exchange

pp. 141-149#

6

5.4@,5.6@

10

W 1/29

Heat Transfer in Tumors

---

7

SP5,start SP6,LR3

11

F 1/31

*Pharmokinetic Modeling

pp. 157-180#

8

5.5@,SP6

12

M 2/3

Pharmokinetic Modeling

pp. 180-190#

9

6.1@,6.2@,LR4

13

W 2/5

Pharmokinetic Modeling

pp. 190-203#

10

6.3

14

F 2/7

Pharmokinetic Modeling

pp.203-214,220-222#

11

SP7

15

M 2/10

Non-invasive Imaging

---

12

6.5,SP8

16

W 2/12

Tissue Engbineering

---

13

SP9

17

F 2/14

*Orthopedics/Robotics

---

---

---

 

M 2/17

Holiday (Presidents Day)

 

 

 

18

Tu 2/18

Blood-Biomaterial Reactions

pp. 65-66

---

--- (Engin. Week)

19

W 2/19

Biomaterials

---

---

--- (Engin. Week)

20

F 2/21

Biomaterials

---

---

--- (Engin. Week)

21

M 2/24

Membrane Transport

pp.229-248,254-256#

14

SP10

22

W 2/26

Membrane Transport

pp.248-254,256-266#

15

7.1, Term Paper critique

23

F 2/28

Drug Delivery Systems

---

16

7.3@

24

M 3/3

Artificial Pancreas

---

17

7.5@,SP11,SP12

25

W 3/5

*Kidney Analysis/Models

pp. 269-284#

---

Term Paper draft (2 copies)

26

F 3/7

Kidney Analysis/Models

pp. 284-291#

18

8.1@,8.2,8.3

27

M 3/10

Kidney Analysis/Models

pp. 291-297#

19

8.5@

28

W 3/12

Artificial Kidneys

pp. 301-314, History I#

---

---

29

F 3/14

Artificial Kidneys

pp. 314-331, History II#

---

---

30

M 3/17

Artificial Kidneys

pp. 331-336, History III#

---

---

31

W 3/19

Artificial Kidneys

---

20

9.1

32

F 3/21

*Pulmonary Physiology

pp. 341-354#

21

9.2@,9.3@,9.4@

33

M 3/24

Pulmonary Physiology

pp. 354-370#

---

TERM PAPER DUE

34

W 3/26

FIELD TRIP

---

22

10.1,10.2@

35

F 3/28

Pulmonary Models

pp. 371-381#

23

10.4,10.6@

36

M 3/31

Pulmonary Models

pp. 381-392#

24

10.7@

37

W 4/2

Artificial Blood

 

25

10.8,SP13

38

F 4/4

Artificial Oxygenators

pp. 399-426#

---

---

39

M 4/7

Artificial Oxygenators

pp. 427-437#

---

---

40

W 4/9

*Term Papers

---

26

11.3@,11.4@

41

F 4/11

Term Papers

---

---

---

42

M 4/14

Term Papers

---

---

---

Final Exam: Wednesday, April 23, 2:30-5:30 p.m.

*This class will begin with a mini-exam

@For this problem, see the notes below

#There are reading questions due for this reading assignment

PROBLEM NOTES

2.1 a) In Table 2.1, tidal vol. and ventilation rate refer to dry air. The volume of water in expired air is (p. 28)

volume of water = volume of air [partial pressure of water/(760mmHg-part.pres.of water)]

where the partial pressure of water at body temperature is discussed on p.28.  How does this volume of water loss compare with daily water loss in the urine?

b) Start with values of ml (STP)/min given in the text (reminder for those who havenít had chemistry for a LONG time: you will need the ideal gas law.)

c) "Solids" refers primarily to NaCl; assume 0.14 N NaCl in the urine  (Note: for NaCl, 0.14N is the same as 0.14M.)

2.3 Compare your answer with that of 2.1c.

2.5 How does the stroke volume you found compare to the stroke volume under resting conditions? (Write the answer to this question in your homework also.)

3.7 The values given in the problem are way out of harmony with reality. For your homework, replace the values with the following:

Tube diameter:

0.15 mm

Tube length:

3 mm

Core region volume:

0.0475 mm3

Peripheral annular region volume:

0.0055 mm3

Total flow rate:

3.30 mm3/s

Core flow rate:

3.28 mm3/s

Peripheral region flow rate:

0.02 mm3/s

4.1 The answer is not quite the same as the value in the table (the table value appears to be based on r=1.000)

4.2 Remember, gmean = (Integral of g dA)/Area

4.3 It is easier to rewrite the velocity equation given in problem 4.2 in terms of vmax, which equals 2vaverage for Newtonian flow.

5.3 Part c): "Net" loss means loss to the environment minus gain from the environment (not including the sun)

Part d): For Pa, see the appendix to get the water partial pressure for 100% humidity, then multiply times the relative humidity

Part f): The ratio (moles H2O/moles air) equals the ratio of their partial pressures (see the notes above for problem 2.1). Further, this can be converted to (mass H2O/mass air) using the molecular weights, where MWair can be assumed to be 29.

5.4 Is the given value of It reasonable in light of the discussion on page 129? How does the answer change if It = 0.12ƒC hr m2/kcal?

5.5 Assume that the heat capacity for the "core" is 0.86 cal/gƒC and that the blood leaves the "core" at the "core temperature. Then write that the sum of the heat losses minus heat gains equals the rate of decrease of heat content (-mcoreCp,core dTcore/dt). This will lead to a first-order differential equation to be solved.

5.6 a) Assume that the correlations given by Cooney (based on the pressure at sea level) apply.

b) Because the mountain climbers are not at sea level, will their water loss be smaller or greater than what you calculated in part a)? Explain your answer. (Hint: See the notes above for problem 2.1)

6.1 After substituting Eq. 6.4 into Eq. 6.3, note that

eat dy/dt + eat ay = d/dt(y eat)

where a = ke + km. The last sentence in the problem statement means "What happens to B as tó>infinity, and what is the significance of the result?"

6.2 Assume that urea production occurs in both the visceral tissue and the lean tissue compartments according to

rate of production = k/(a + conc.)

where "k" and "a" are constants particular to the compartment.

For convenience in labeling, assign the following number labels to the compartments:

CSF

1

Brain

2

Visceral Blood

3

Visceral Tissue

4

Lean Blood

5

Lean Tissue

6

 

 

6.3  Cooneyís answer in the back of the book is wrong.

7.1  Remember, 0.14 N NaCl will dissociate into 0.14M Na+ and 0.14M Cl-.  Also assume:

cH2O = 55.14 gmol/L

V = 18.136 cm3/gmol

R = 82.05 atm cm3/gmol K

7.3 Use Cooney's simplified treatment for non-electrolytes, and neglect the transport of species other than urea. The "partition coefficient" mentioned in the problem is the equilibrium constant K = cm/cs

7.5 Assume that the solutions are sufficiently dilute that g≈1. Also, on the side with no protein, how are the Na+ and Cl- concentrations related?

8.1 Even though Cooney's anatomic concept is wrong, let's assume that we can model the flow area between the inter-digitating fingers as an array of pores with dimensions given by Cooney. Assume Poiseuille flow. Also, note that npr4 = (npr2)r2 = (pore area)r2

8.5 Set up a balance on the drug in the body, where the output is glomerular filtration and the input is the same flow rate of fluid (drug-free) recovered from the tubules. Assume that the drug concentration in the glomerular filtrate is the same as in plasma. The blood flow to the kidneys (1200 ml/min) does not enter into the equation.

9.2 Work this problem in two ways: 1) as shown in the example problem on pp. 331-334 where a simplified form of the Extraction Ratio E has been used, and 2) using the exact relationship for E as given on p. 322. Explain the difference in the answers from the two methods in terms of the physical significance of the assumptions? Which is the more realistic answer? Why? Use the "more realistic" method in solving problems 9.3 and 9.4.

9.3 See the note from problem 9.2.

9.4 See the note from problem 9.2.

10.2 After the first breath, assume that all the breaths taken are of air.

10.6 Assume that the KD given on p. 352 for respiratory gases in aqueous fluids is the same for the whole body. Cooney's answer is wrong; he assumed that the diver was breathing 100% N2.

10.7 The relative competition for Hemoglobin sites is reflected by the relative magnitudes of the O2 partial pressure and the "effective" CO partial pressure (equal to 210 times the actual partial pressure). The CO acts somewhat like nitrogen because it is not being metabolized, so assume that the partial pressure of the inspired CO will be "diluted" in the alveoli at the same ratio as the Nitrogen partial pressure is decreased. Also assume that the partial pressure of O2 in the alveoli is the same as always. The fraction of hemoglobin sites bound by CO can be estimated by

FractionCO = PCO,eff/(PO2 + PCO,eff)

11.3 For the O2, RTot = 2RMem, so KTot = 1/RTot = 1/2RMem = KMem/2

11.4 The concentration of O2 in the blood at the surface is different from those on p.420 of the text.  To get cs (t), the Henry's Law constant is

0.024 ml O2 (BTP)/(ml blood atm)

 

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