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TJ Paulus’s Interview

Manhattan Project Locations:

TJ Paulus is an electrical engineer at Oak Ridge National Laboratory. In this interview, he discusses how he first became interested in science as a child. Paulus describes research he has conducted over the course of his career in nuclear instrumentation and electronics, including on nuclear reactor reflood studies and positron imaging for medical purposes.

Date of Interview:
April 25, 2018
Location of the Interview:


Cindy Kelly: I’m Cindy Kelly, Atomic Heritage Foundation, and today is Wednesday, April 25th, 2018. I have with me TJ Paulus. My first question for you is to say your full name and spell it.

TJ Paulus: Sure. Thomas Joseph Paulus. The last name is like the boy’s name Paul, P-a-u-l-u-s.

Kelly:  Great. The first thing I want to know about is something about you—your childhood, where you were born and when.

Paulus: Born July 19th, 1939, on what is now part of the University of Tennessee campus. Dad was a professor at UT [University of Tennessee]. When I was born, he got his PhD at Cornell and taught a couple of places before he moved here in 1938. Mom was at home for a while. She ended up teaching multiple handicapped children, which was quite an exercise for her.

About me: growing up, I’m told I was a pretty wild little kid, running around, doing lots of different things. Dad put my crib or playpen on the front porch, and I kept climbing out of it and running around the neighborhood. He built it up and finally built it up all the way to the ceiling, so I didn’t have a way to get out. Instead, I took off all my clothes, and threw them around. That was early on; I don’t remember all of that.

One thing related to Oak Ridge, though, is, we had women staying with us who worked somewhere in Oak Ridge. I don’t remember the details. But we had a very nice house with room for six upstairs, and they worked there during the war years. I just remember all these women wandering around, and I had no idea where they were from and or what they were doing until later.

I did grow up in Knoxville, went to school here in Knoxville. Two years away for Xavier University in Cincinnati, then back to UT to graduate with my Bachelor’s degree. Then, Uncle Sam and the Army for a couple of years. Back to UT as a fulltime instructor, working on a Master’s and PhD.

It was while I was teaching at UT, my professor there was T. V. Blalock, or Theron Vaughn Blalock, who was in the Instrumentation and Controls Division here at the lab [Oak Ridge National Laboratory]. He taught one day a week, so he had four days at the lab, one day teaching. I was very blessed to be able to work in his lab the summers of my first three years back in graduate school. Learned a tremendous amount from him on how to do signal processing of nuclear signals, which led to a later career in nuclear instrumentation.

Kelly: Let me back up here just a second, because I ask this of everybody and I don’t want you to be left out. When did you first become interested in science, and what made you want to become a scientist?

Paulus: Early on, I remember my dad and mom both being very, very good teachers. Dad took me to see Fort Loudoun Dam when it was being built, so I could be aware of what this big structure was. We went down when they expanded Neyland Stadium to see how that was.

Then a little later on, I was interested, as some boys become, in firecrackers. I found that I could explode them using a battery and a little bitty wire around the wick of the firecracker, plug in the battery, and go “Poof.” With that much fun, I went off with finding a particular kind of firecracker called a bulldog, that was unique because you could take the end off of it, and you could get the explosive out.

I took the powder from one, dug a hole—Dad was with me watching—worked my wire, hooked it to the battery. “Boom!” Made a little bigger hole. I put in the powder from three of them down in this little hole, did it again, and, “Poof,” a little bigger hole. Then I took the powder from twelve of them and put it down in this hole, filled it up again. “Boom!” Great big hole, rocks, sticks flying all over the place. Dad looked around from behind a tree and says, “I think that’s enough.” So that was early interest in electricity.

Kelly: That’s great. Did you run behind a tree, or were you sitting right there?

Paulus: Of course not. That was in the middle of the experiment.

Kelly: That’s great. Do you remember being interested in science when you were in middle school or high school?

Paulus: Certainly. One thing I remember partly being told is that I liked girls. In first grade, I would try to go sit with the girls rather than with the boys, because I thought they were nicer. I sometimes was wrong about that.

Later on, I was involved in public speaking. My first speech was, I think in first or second grade, on how to brush your teeth. Dad was very much into public speaking. This was part of his professorship, and teaching people in the state. In high school, freshman year, I won the oratory contest in our school. In junior year I won it for the Catholic schools in Tennessee, I won the men’s oratory contest there. Did high school debate. Because I’m such a tall, lanky guy, I decided I shouldn’t play basketball. Instead, to go to all the games, I was a cheerleader. I was, again, the thorn among five roses.

Kelly: That’s great. Good stories. Let’s see, you got through your PhD and then you had a mentor that brought you to the lab?

Paulus: My mentor worked with a project at the lab, was while I was still [a student]. I came back from the service in fall of ’65. He was my professor. I probably had him as an undergraduate, too, since I came back to Tennessee because of an excellent engineering program and the closeness to the lab, as well as TVA [Tennessee Valley Authority]. I knew that there was a market for engineers.

Besides, I like Tennessee. The summer of ’66, I was working in the Instrumentation and Control Division, which Kaz Perkowski was the head of.  T. V. Blalock, I worked in his lab doing instrumentation development. Had wonderful lunch discussions with him, with Dr. Charlie Nowlin and Manfred Kopp, that were all very, very good and very, “Teach you, learning from me.” I did that for the Summer of ’66, ’67, and ’68.

In that time, I was teaching, and I didn’t like the textbook. Because the text was written by the head of the department, I was kind of quiet about not liking it. Instead, I used class notes, and I would type up the class notes. Sometimes people would declare they were in a foreign language because of all of the misspellings, but I typed-up class notes, and ran them off, and sold them to the students. I ended up with two semesters’ worth of material.

The department head said, “I understand you’re not using the text, but you’re using class notes. Could I see them, please?”

I said, “Here it comes. I’m going to be shot on sight, fired, run out of the building.”

Instead, he looked at them and said, “Oh, my. I had no idea you had done this much. Would you like to write a book with me?” That book was Applied Electronics, published in 1972, and it’s still in use at the University of Tennessee. That’s over forty years.

What is unique—and I think I can attribute to my work at the lab—is I would take the various electronic circuits, calculate what the results should be, build them and test them and see what the actual results were. Then use that as a vehicle for learning for either the limitations for analysis, or mistakes in the analysis. That was very, very powerful, and I think it’s what has kept it alive so long.

Kelly: Or it could be a mistake in actually making it. People could have made the circuit the wrong way.

Paulus: Right.

Kelly:  Or made some error.

Paulus: When I was teaching, I would have students for their labs, instead of being a “go-in-and-copy-down-what-was-done,” I would give them a design problem. Each was set up in groups of two or three, and each group had a slightly different problem. I went to one, and he had all the parts there, but they weren’t put together. I say, “You can’t measure anything until it’s put together.”

He says, “Oh, no, I’m afraid I’ll burn it up. I’m not going to do that until I know it’s going to work.”

No, it doesn’t work that way. You’ve got to build to test, you can’t test without actually having something. That was very, very instructive.

I taught here at the lab, technicians and also the engineer science review course, and some other courses in the course of my career. I stopped working at the lab summers in ’69, and I worked instead at ORTEC [Oak Ridge Technical Enterprise Corporation]. ORTEC was a spinoff of the lab in the early ‘60s, making radiation detectors. They’re just down the road. It’s now AMETEK.

Many of the people there were former employees at the lab and UT graduates. Probably the most famous in this area would be Terry Douglas, who headed up the CAT scan imaging approach and just did a beautiful job, and supported a lot of engineers who worked at the lab and at ORTEC. When I went to full-time in ’72, I worked at ORTEC, because it looked like a better chance to do things. And it did.

When I came back to work with the corporation, it was bought by a company called EG&G—Edgerton, Germeshausen, and Grier—which also dated back to the Manhattan Project.

When Mike Roberts in the INC Division was building instrumentation to study reactor reflood, he contacted us and we went in as a contractor, EG&G did—and I reported to upper echelons of EG&G—to take his concepts and his [inaudible] boards and reduce them to practical instruments. That was very useful for a couple of years.

We did the instruments for two German reactors and two Japanese reactors, and were doing some for here. When Three Mile Island occurred, then we had our own lab to work with, since that was such a problem area. That ended up the AIRS Project, Advanced Instrumentation for Reflood Studies, AIRS.

You have a reactor, and you blow out, and water is coming down. The instruments would go in, and actually measure the two-phase water/air/steam mixture and determine how much of it is water, so you could tell if you’ve reflooded the reactor to cool it down, so it will not explode or do anything else. The reflooding was literally pouring all sorts of water, and the instrumentation was to determine how well you were doing.

Kelly: Or how much of it was turning to steam.

Paulus: Turning to steam. You can’t look inside with all this boiling and carrying on. It’s a way to actually test the environment—that is, you have been able to create or adjust or change. Is it a real problem still, or not?

Kelly: Are these detectors located at all heights of the reactor, or is it something you would insert at a time of crisis?

Paulus: I think they were in at different sides, but this was a number of years ago and that was the onsite. My job was hook onto to where they had it and process the information in signal processing, not to tell them where to put the detectors.

Oh, it worked by taking two prongs. If I have air, the dielectric constant between these two, which is what the inside of a capacitor is, is that of air. If it’s fully flooded, it’s that of water. When you have steam, it’s somewhere in-between. We were trying to measure how much steam, how dense was the steam, how was it changing as we put more water in, which gave you an idea of the temperature, as well as just the success of flooding it.

Kelly: You call yourself an electrical engineer? Or what is this field that—

Paulus: Electrical engineering covers a tremendous breadth. In fact, now at the University of Tennessee, it’s electrical and computer engineering. Back then, computers were just beginning to become such a tremendous force.

Electrical engineering can be electronics. It can be power, as TVA. It can be systems to control things, control systems, which was the beginning of computer. It can be electromagnetic fields, which would be transmission of data and other things. My part was in electronics, so I was electrical engineering with a major in electronics.

Kelly: But isn’t everything electronics? What is electronics?

Paulus: Oh, electronics would be—particularly from signal processing, if we have a detector, a whatever type of detector, some kind of signal comes out of it. It may be a little burst of electrons, it may be something else that’s changing. Then, how do you translate into something that can be used?

Nuclear radiation. How do I know if it’s cobalt-60, potassium, or some other thing? They have their own signature, their own fingerprint. This fingerprint is different energies that are dominant in this. As you take the measurement, you’re measuring the energy of each event that comes out of the detector. You measure at typically the peak, and then you go over to a memory and add one count to where that energy was.

If I have got an energy of 100, 1,000, or 10,000, I’ll add a count. After I’ve taken lots and lots and lots of counts, I end up with a signature that is just like your fingerprint. You can look at that and say, “Ah, of course. It’s cobalt-60, or iron-55,” because you have taken data that gives you the fingerprint of the actual radiation. That’s one example.

Another one that I was very much involved with was called positron annihilation. Here you have a source that would emit a gamma ray at one energy, and a positron or two positrons. The positrons would meet an electron and annihilate. They would convert completely from a positive ion into a negative ion, which is an electron, and give off two gamma rays that are 180 degrees apart. Take two detectors and move them around, you can see which way things are going.

Positrons live longer in voids, little bitty, like missing an atom in a structure or two atoms. If you look at the lifetime of the positrons, you can actually study the void structure in the material down on the atomic level. Very, very, very precise. That is one thing that is done. 

Positron annihilation is used in medical imaging. If you have a CAT scan, it would be one thing, and the gamma rays are coming out, and you actually go back and you can map the internal organ that you’re looking at where you have a cancer. The positron will become more likely to land there or some other place that would give them, the medical person, a view of what you are down inside. It has lots of applications, not just pure science. It’s taken off into other areas.

Kelly: Did you spend a career at the laboratory or–? 

Paulus: No. I was at the lab off and on over a number of years. Again, the summers and then coming in one day a week every so often to do teaching. Then I spent about two years working off-site, but I was working for someone in the lab. That was back in late ‘70s, early ‘80s.

My career included not just instrument development, but group management, marketing, and a lot of international travel to explain things, either our products or our technology. As my resume shows, I have over fifty presentations, including published articles. My first one was in Russia in 1977, it was nuclear instrumentation. I did one in China in 1981, and then back again a number of times in ’84. India, Canada, lots of places in Europe, and Japan, Australia. Just doing either technical explanations for material, or going in and making a measurement system optimal.

It’s described sometimes that a PhD is one who knows more and more about less and less, until you know everything about nothing at all. One of my trips to China, I was back in the backwoods at a lab. I walked in and this guy looked at me, and he looked over on the wall, where he had an application with my picture on it. “Ooo, ooo!” This was, again, the very small world that he would, in the backwoods of China, recognize someone in this very, very, very small area.

I’m very sensitive to not sharing information that was not public domain. I was not in security clearance material. I did that back in the service. But that kind of explanation—“Slow English” was a language that is understood by most technical people around the world, which I found very useful. 

Other ones I did were a system which reduces background, so you can have a more clear picture of this energy by subtracting background information. That’s another fairly complicated system. These are ways to enhance knowledge by having improved instrumentation, and then be able to communicate it.

Kelly: That sounds like a great combination.

Paulus: I’ve probably been in 35 different countries. What has struck me so much is, while we have superficial differences that are real, once you can get down and get to know the people or get into the homes, the values are so common. Family, children, looking after each other. I was so struck.

When I was going back to teaching after I retired from ORTEC, I taught as an adjunct professor at UT a senior- and graduate-level course. About half the class were foreigners, a lot from China and Europe. Getting to deal with them was fun, and I would invite them out to our house before the final exam. We live on the lake, on Tellico Lake. Just a nice time. I said, “This is an ‘Ain’t no hard feelings’ party. Want you to come and have a good time and not be mad at me for the class.” They would come and just had a wonderful time. It was not often that these foreign students got into a home to see what it looked like. That was part of, I felt, my mission: to convey that we’re similar, we’re not bad guys.

Kelly: That’s great.

Paulus: I trace this approach back to my days at the lab, and working with the people at the lab.

Kelly: Do you want to expand on that?

Paulus: Vaughn Blalock, who I mentioned in the beginning, is probably one of my true heroes. I worked with him teaching, had him as a consultant when I was involved in a patent infringement lawsuit. He was our expert witness. Tremendous insight, communicator. Wonderful, wonderful person. Bright, intelligent, wonderful family. His son is now a professor at UT, electrical engineering, Ben Blalock.

Charlie Nowlin: very, very, very bright, and pushed me insights, and made me go off and buy old books that had these principles of electronics back in the ‘20s. Not everything we’re thinking of is new. It’s a different form factor, but it’s the same principles. Dragging me to go look, that not everything is my first idea.

People like that. Then, how do you build and evaluate realistically an instrument, so it can be used realistically. That help any?

Kelly: Yep. This is a topic that’s of great interest to our project. Our project is funded by IEEE [Institute of Electrical and Electronics Engineers].

Paulus: Yes. I was advisor to IEEE at UT.

Kelly: Were you?

Paulus: Student chapter, yes. We had 150 to 200 active students. One of the things I took over was the coffee pot. Down in the breakroom, we had a little coffee pot and a little tin can for putting the money in. It grew and grew. I had the students take the dollar bills out so nobody could see them, but we would use the funds from that coffee pot to pay for a student party at the end of each quarter, or at the spring. We would invite the faculty. It was again, a great building of student-faculty camaraderie and awareness of each other. Just fun.

Kelly: Very much. That’s great.

Paulus: I was once declared to have the largest uncontrolled treasury in the college, and it’s probably true.

Kelly: That’s great. But it worked.

Paulus: It worked.

Kelly: That’s great. You keep up with your former students?

Paulus: Some I do, and some I don’t. Some have contacted me, which I really appreciate. But things are moving into the next generation.

My wife went back—I was having so much fun in engineering—she went back and got a Bachelor’s in electrical engineering at UT. Went to work at Y-12 and K-25, and got her Master’s degree. So we’re both EEs.

All three of our kids are EEs. Mike, he’s here at the lab. Our daughter Kathy is in software quality control, and has a company here in Oak Ridge. Her husband, Dr. Bill Toth, works at the lab. Our son, Rick, is a sad case—he’s a mechanical engineer. But he married an electrical engineer and after five children, she just finished her PhD a couple of years ago in electrical engineering from Georgia Tech. Not bad.

Of the seven grandchildren out of college, five are either engineering or computer science.

Kelly: Oh, my goodness.

Paulus: It’s a bloodline problem we blame my mother for.

Kelly: For heaven’s sake, that’s remarkable. I’ve lost track, but that sounds like twenty-five engineers.

Paulus: The one that was married this last weekend, he’s in aerospace engineering working on a PhD. The other granddaughter is getting married in May, her husband is a chemical engineer, and her undergraduate degree was chemical engineering. So, yes.

Kelly: Wow. That’s incredible. That’s “Great minds think alike.” That’s great. What fun. Is there anything that I haven’t asked that you’d like to talk about?

Paulus: I have told students and people many times that engineering is a great place to be, and a great place to be from. I think that is so true, whether you go into teaching, medicine, industry.

It is education that I attribute, again, back to the people here at the lab for how they worked with the electrical engineering department at UT as a structure, that so many of them floated back and forth. I think the lab has been a fundamental groundwork, or support structure, to help people grow up and be very, very accomplished and real contributors to society.

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