Akron Phy sics Club
Meeting Announcement: MONDAY, January 22, 2007 - TANGIER, 6:00 PM
For our speaker of the New Year will be astrophysicist Prof. Glenn Starkman of Case Western University, whose subject is:
THE SHAPE OF THE UNIVERSE
As Dr. Starkman explains, “We now possess a wealth of data about the properties of our universe on the very largest scales. On the one hand this data is well explained by Einstein's theory of gravity — General Relativity. On the other hand, the very odd behavior of the Universe on these largest scales requires intellectual contortions to make the whole theory work. This could be an early sign of the need for a new understanding, or just the way the universe works.”
Minutes, January 22, 2007
The first meeting of the new year brought out 26 guys and girls, including our speaker for February, Claire Tessier, as well as first timers Volker and Caroline Kusterer, recent arrivals from Munich — who will be gracing Akron for the next year or two on a marketing mission. And we welcomed the return of student Adam Reed.
Chairman Ernst von Meerwall’s calling on Treasurer Dan Galehouse for a statement of our wealth yielded a complex arithmetic analysis (which was lost on this secretary because he skipped the half of second grade when his parents moved to another school zone), the net of which, however, was that our treasury had increased from $66.60 to a new balance of $71.60. Somehow it seemed improper such serious quantified data about our financial integrity should produce a roomful of laughter. Dan was followed by Program Chairman Sam Fielding-Russell, who reviewed the excellent set of programs he has set up for the rest of the year.
Invited by Chairman Ernst, Bob Erdman told the group about a contingent of 14 of us who ventured to Hudson’s Actors’ Summit Theater to see QED, a play about Richard Feynman, starring Neil Thackaberry in an almost solo role — and who, Bob explained, convinced the audience that he really was a physicist. “He acted just that crazy.” (As we would later learn, our speaker had met Feynman and had spent several hours talking physics with him not long before the famous physicist’s death.)
At this point, Ernst introduced our speaker, Dr. Glenn Starkman, Professor of Physics, Case Western University, whose subject had been billed as The Shape of the Universe. Just listing some of our speaker’s interests made Ernst’s introduction an entertaining short subject in itself, e.g., (1) Starkman’s searching in early background microwave radiation for evidence of non-trivial topology of the universe; (2) determining how best to search for differences between General Relativity and modified theories of gravity that try to explain the accelerating expansion of the universe; (3) investigating the topology of extra dimensions; (4) exploring the possibility that an Aether can replace either dark matter or dark energy or both; (5) arguing against the anthropic principle — and (6) investigating the future of life and thought in the universe.
It has been several decades since mind-expanding drugs were in the news. But on the evening of January 22nd we were treated to a mind-expanding lecture, replete with mind-expanding (indeed universe-expanding) Power Point graphics, presented by Case Western theoretician/cosmologist Glenn Starkman:
Our speaker began by reviewing the history of how the mechanics of the solar system were discovered, of Newton’s working out his theory of gravitation — and how its predictions seemed to be in error in observations of the orbit of Mercury. These questions led to the famous astronomical observations during a solar eclipse in 1919, which showed that the gravity of the sun bent light (actually bent space) as it skimmed past the solar mass, thus validating one of Einstein’s most important hypotheses. Or almost, as it turned out, leading to Einstein’s adding his famous (or infamous) cosmological constant term, which he later called his “greatest blunder” — but which began to be reexamined once again a decade ago.
The greatest contribution of the 1919 experiment, Dr. Starkman believes, was that it started a revolution in how scientists viewed space, causing them to no longer think of space as static, but rather as a dynamic object, which could, perhaps, expand or contract or change with time. This new dawn of cosmic cognition led to recognizing the existence of black holes — objects with a mass between a million or a billion times the mass of the sun, one of which seems to be present at the center of every galaxy. It is now believed that that the amount of cosmic stuff these objects have drawn in early in the life of the universe has resulted in some of them becoming quasars — objects brighter than all the stars in the galaxy.
On the screen we saw our speaker’s great collection of galaxies, the light from some of which has taken 100,000 years to get here. Surprisingly, it has been discovered that the rotational velocity of their starry galactic components levels off and becomes essentially constant as the radius from the galactic center increases — quite a different situation from the way gravity operates in our own planetary system. This seems to indicate that there is way too much gravity out there at such (multiple kiloparsec) radial distances for Newton’s and Einstein’s theories to digest. Why this is so boils down to two choices: either there is more stuff there than we perceive, or the law of gravity is wrong! It was this dilemma that gave birth to the idea of dark matter.
Our speaker described some of the elaborate experiments being conducted around the world at the bottom of mines and in other unlikely places in an attempt to detect particles of dark matter — which apparently make up much more of our universe than ordinary matter. It affects not only what goes on in the interior of galaxies, but also in the behavior of clusters of galaxies, which fail to behave according to Newtonian gravitational theory.
We then saw some Hubble telescope images in a part of the sky with very few foreground stars, which have permitted us to see galaxies at the edge of the known universe, hundreds of millions of light years from the Earth — some dating back nearly 14 billion years, well before our Earth was born. And no matter what direction we look, they are all moving away from us. And the farther away they are, the faster they are moving. The explanation for this is not, of course. that we happen to live in the center of this expanding universe. Instead, our speaker offered us the analogy of a lump of freshly mixed raisin bread dough in which each of the raisins is moving away from every other raisin as the dough rises (a somewhat different concept than that of a Big Bang explosion originating at a single point in space).
It was Edwin Hubble who discovered that the universe was expanding — although, as it turned out, he got the rate of expansion wrong by a factor of ten because he was looking at objects that were too close. Recent data has show that those relatively close to us (i.e., ones 3 million light years distant!) are moving away at the rate of 72 kilometers per second. Those 30 million light years away are moving at the rate of 720 km/sec . . . and so on.
Moving on to some of the phenomenal phenomena that result from living in an expanding universe, Dr. Starkman addressed the incredible homogeneity of the universe, which (having cooled enormously since the Big Bang due to the expansion), is everywhere almost exactly the same temperature — specifically 2.728 degrees Kelvin (varying directionally by a few parts per hundred thousand). The Standard Model predicts that exponential acceleration of the expansion of the very early universe occurred (during the first billionth of a billionth of a second!), driven by “vacuum energy.” And minor fluctuations in that vacuum are where stars and nebulas originated.
He also described recent research on supernovae, whose distance can be determined by their cycle of brightness and dimness. And one indication that has resulted from this work is that during the last few billion years the rate of expansion is accelerating — leading to the hypothesis that we are dealing with a new form of energy. But new data is pouring in at the present time, on the cyclic nature of galaxies, on parts of the universe that vary slightly in temperature, areas which vary in density, as well as on dark matter and dark energy. So stay tuned!
A few gems that surfaced during the Q&A period: If the universe is a closed system, the time for light to go around it is 74 billion years. Black holes eventually begin to evaporate. And a depressing but verifiable slogan: Entropy always wins!
Meeting Announcement: MONDAY, February 26, 2007 - TANGIER, 6:00 PM
Our February speaker will be Dr. Claire Tessier, Professor of Chemistry, the University of Akron. She will be talking about:
THE BIOMINERALIZATION OF SILICON
As Prof. Tessier explains, “A relatively new and challenging project in our group concerns silicon biomineralization. Diatoms, certain sponges, and plants contain deposits of amorphous silicon dioxide that are produced under mild conditions and, often, in complicated shapes. An understanding how these organisms deposit a mineral may suggest methods that can be used by chemists to make ceramic materials in specific shapes. The overall goal of our research is to understand the inorganic chemistry aspects of the biomineralization.”
Quite aside from the interesting practical applications of her research, just understanding how and why such a biochemical process occurs sounds fascinating — at least to this chemical engineer.
Minutes, February 26, 2007
Typical for February (a good month to be in Florida!), our meeting was held on a cold, damp, gloomy night, which decreased our attendance a bit, but still brought out most of our regulars, plus student Carlos Barrio. Part of the decrease was the result of Milian’s having taken Bill Jenkin to the ER earlier in the day — and we’re pleased to advise that he was out and about two days later.
Invited by Chair Ernst von Meerwall, and in a ceremony worthy of the geometrical concepts physicist, Treasurer Dan Galehouse expounded on the mathematics involved in the inadvertent reduction of our club’s treasury from $71.60 to a new balance of $67.60 — news which failed to daunt the lean, Spartan audience.
When called upon, Program Chairman Sam Fielding Russell divulged the longer title of Dr. Klaus Fritch’s talk recorded above; and then he “clarified” it: “Bubbles coalescing under pressure, yielding light!” In April, Sam added, we will hear from UA Prof. Narender Reddy, whose title is “Direct Control of Virtual Environments Using Electromyographic Signals.” And for our last program of the year, in May, we will hear from Prof. Kevin Cavicchi (also U of A), whose subject will be “Self-Diffusion in Ordered Block Copolymers.”
Sam then made an appeal for possible subjects and speakers for next year that might be of interest to the membership — a request that was reinforced by Chairman Ernst, and one since taken up in e-mails by Charlie Wilson. The plea has been answered with wish lists from a number of members, but Charlie and Sam could use more.
Ernst then introduced our speaker, Dr. Claire Tessier, Professor of Chemistry at the University of Akron, whose subject was The Biomineralization of Silicon. It became apparent that Dr. Tessier was born with a Periodic Table tattooed on her tongue. Accordingly, she explained, her parents gave her a chemical name, which she showed us on the screen, spelled out with the symbols of the elements — including, appropriately, some rare ones:
C La I Re Te S Si Er
(carbon, lanthanum, iodine, rhenium – tellurium, sulfur, silicon, erbium)
Her trademark, in miniature, appeared on every slide in her animated Power Point presentation, which polymerized inorganic polymers before our eyes.
Showing us a Periodic Chart of the elements, our speaker called our attention to three of them, which fluoresced in green: aluminum, silicon and phosphorous — elements which have dominated her life from the time she wrote her PhD thesis. For her they symbolize the subtitle of her talk: “How to Survive as an Inorganic Chemist in a Word Gone Bio.” To achieve that objective, she resolved to come up with inorganic projects that related to life. She settled on biominerals, which are frequently incorporated into biological species — elements like calcium, silicon, iron, oxygen.
She gave us an example — a really important inorganic compound in the very structure of ourselves. Literally: (Ca5PO4)3(OH) is the largest component in our skeletons, bones, and teeth, and those of other primates. But these body components also contain a couple of percent of SiO2. It has been recognized for less than ten years that silicon is important to human nutrition. (And beer, we learned, is an excellent source of silicic acid!)
Shells are mostly CaCO3. Silicon biominerals are found in abundance in plants. Rice is 85% silicon dioxide. The skeletons of sponges are silicon dioxide. Diatoms, microscopic single-celled algae, are made of amorphous silicon dioxide. And they’re so numerous that they perform a vital function for nature: 25% of all fixed carbon is synthesized by diatoms, which absorb carbon dioxide and emit oxygen in the process. And in concert they produce 6.6 x 109 tons of silica (hydrated SiO2) annually. [Is it any wonder our beaches are bordered with sand?]
Dr. Tessier offered an explanation of the mechanism of catalysis — one which turned on a light in the aging brain of this chemical engineer: Silicon minerals, it turns out become the templates for many organic molecules, e.g. silicateins, which are enzymes that, in turn, speed the growth of proteins (which are amino acids).
In discussing possible future projects for her research and possible new materials to be synthesized, our speaker offered some possibilities that presently exist in her imagination, e.g. composite biomineral materials, whose properties could vary with the structure of the matrix, and the ratio of bio to mineral in the matrix. “If your template is biodegradable, then we should have a biodegradable material,” she postulated. “Maybe a ceramic with resistance to shattering — perhaps a ceramic engine!”
She went into detail about some of her current projects, especially those involving silicon sol-gel products (SiOH suspensions), like those nature uses in the structure of single-celled sea life.
She showed us the skeleton of one species of diatom, which displayed a magnificent regular structure of agglomerated particles of specific sizes. It looked like a microscopic stack of coins or cookies, each of which had intricately milled edges of different designs. The resulting sculpture could also be seen as a tiny, beautifully woven basket. The microorganism had precisely assembled the layers into a tiny cylinder having smooth, closed ends with holes to admit seawater for metabolic processing. When dividing, it splits in the middle and then grows new surfaces on the open ends.
“These lowly biological creatures can do a lot more than we can now,” Claire admitted. But an elaboration of her current efforts with sol-gel chemistry in the presence of biological molecule additives (e.g., amines leading to silica proteins) made it obvious that she is trying to catch up!
Meeting Announcement: MONDAY, March 26, 2007 - TANGIER, 6:00 PM
Our March meeting will feature the return of Prof. Klaus Fritsch of John Carroll University, who last graced our schedule in January, 2006, when he enlightened and entertained our aeropleustic psyches with his presentation on “The Physics of Flying.” This time his subject once again sounds intriguing, if not caliginous:
SINGLE BUBBLE SONOLUMINSESCENCE:
LIGHT FROM SOUND
Minutes, March 26, 2007
Called upon by Chairman Ernst von Meerwall, Treasurer Dan Galehouse, two days out of the hospital, gallantly reported upon what our Chair characterized as the “state of our financial decrepitude.” And, indeed, it seemed that some repair was at last needed. Starting with a treasure of $67.60, Dan took us through the math, which, including the ubiquitous fruit plate factor, resulted in a new balance of $51.60, a figure which may constitute a new low. Accordingly and by acclamation, a new dinner charge of $19.00 was approved for future meetings.
Meanwhile, founder/club bylaws author Charlie Wilson advised that we can all expect to receive an e-communique seeking and/or approving nominations for club officers for the club’s new year beginning in fall. At which point Chairman Ernst introduced our speaker, Prof. Klaus Fritsch of John Carroll University, who last graced our schedule in January 2006, when he enlightened us about The Physics of Flying. This time his intriguing topic was Single Bubble Sonoluminescence: Light from Sound.
Dr. Klaus began with a history of the subject. It goes back to 1917, when Lord Raleigh was asked by the British Royal Navy to review the problem of ship propeller corrosion apparently due to cavitation. In the process of his investigation, Raleigh discovered the light phenomenon. Then in 1934, two experimenters at the University of Cologne used ultrasound to accelerate the development of photographic plates, only to discover fogging of the plates due to the light developed by the collapsing of multiple cavitation bubbles that were created in the vibrating developer. Single bubble luminescence was first recognized in 1989.
As our speaker explained, “Single bubble luminescence occurs when you trap a bubble and then make it collapse. When the bubble collapses you concentrate energy, which causes the emission of light pulses as well as other interesting phenomena.” He showed us the apparatus that he uses to create it — a 250 ml spherical flask filled with water and a pair of ring transducers to vibrate the container at its fundamental resonant frequency(about 28 kHz in his experiments a pitch well above the range of human hearing — thankfully for the experimenter, since the sound level could be about 110 dB).
His apparatus generates a bubble in the center of the flask. There are three forces acting on the bubble: gravity, which is negligible, buoyancy, which tries to lift the bubble, and something called the “Bjerkness Force,” which is proportional to the volume of the bubble and the pressure gradient. The bubble starts out at about 5 microliters, slowly grows to 50 µl, then suddenly collapses to 0.5 µl with the pressure peaking at 104 atmospheres — a change in volume of about a million. The particle density in the bubble is about 1021 per cc.
The liquid environment, on the other hand, experiences negative pressures, which literally tear its structure apart — the cause of cavitation. The localized energy involved the collapsing is enormous, producing temperatures in the neighborhood of 105 Kelvin. Each time the bubble reaches its minimum diameter, a spike of light is emitted. Dr. Fritsch showed us some movies of the process, the bubble appearing as a bright blue point visible in the center of the flask. The spectrum of the light peaks in the ultraviolet. The duration of the pulse is 50 to 200 picoseconds.
The phenomenon has attracted many researchers, some of whom have tried different combinations of liquids and gases, as well as altering the frequency of their transducers. David Flannigan and Kenneth Suslick used sulfuric acid (diluted with 15% water) with argon as the gas — and they recorded light pulses two thousand times brighter than air-water media. They measured temperatures inside the bubble of 12-15,000 Kelvin — but interestingly a lower temperature produced more light. The light, however, is not from thermal emission. The glowing bubble is actually dense, hot, optically opaque, highly ionized plasma.
One experimenter took his apparatus aloft to measure the effect of a zero-gravity environment as well as that of a 2-g environment. Another has investigated producing the collapse with what is known to chemical engineers as “water-hammer.” But probably the most sensational work on the subject has had the objective of determining whether nuclear fusion could be produced by the process. The experimenters used acetone (C3H6O) in which the hydrogen had been replaced by deuterium (C3D6O) and managed to get the negative pressure in the liquid down to minus 14 atmospheres while bombarding it with neutrons at the rate of 400,000 per second to produce thousands of bubbles (inviting criticism for injecting neutrons while looking for neutrons). The “pioneers” claimed to have found evidence of tritium — a result that has not been reproduced by others [shades of the “cold fusion” hoax?].
Meeting Announcement: MONDAY, April 23, 2007 - TANGIER, 6:00 PM
Having actually made our way past the Vernal Equinox, our first program amid palpable signs of spring our speaker will be presented by Dr. Narender P. Reddy, Professor of Biomedical Engineering at the University of Akron, who will describe his work on the unique subject of
CONTROLLING REMOTE ROBOTIC "HANDS"
To conduct experiments or to operate equipment in environments in which human hands (or their attached people) might not survive, a need that has been growing for direct biocontrol in such diverse disciplines as aerospace, medicine, entertainment (games), and rehabilitation (where the corresponding anatomical part may not exist). Current interface solutions include the Cyber Glove, exo-skeletal devices, and other kinds of sensors that are externally worn by the operator. These are less than optimum for some applications and can be restrictive. Prof. Reddy has been working on systems which utilize skin-surface voltages (electromyographic signals) arising from the muscles of the remote operator — systems which permit greater freedom and accuracy of both position and the amount of force applied by robotic “fingers” in the virtual environment. Some include hybrid intelligent systems consisting of fuzzy logic and neural networks for dynamic control of the virtual finger/wrist joint positions.
Minutes, April 23, 2007
Amid signs of impending summer with temperatures approaching 80° F, (having skipped spring!) we had 23 in attendance for our April meeting. Chairman Ernst von Meerwall introduced two visitors, Nancy Bulger, who was a physics student at the University of Akron during the period when Charlie Wilson headed the department. Nancy had brought her daughter along, so we were also privileged to meet Laurie Chevalley.
Once again, our meeting was launched with a rousing report by Treasurer Dan Galehouse, but this time with an unexpected flourish: For the first time in recent memory, our wealth had actually increased(!), taking off from a starting balance of $51.60 to a triumphant new achievement of $60.60 — due to our treasurer’s perspicacious one-dollar increase in our charge for meals (now $19). And FOI, Dan reported that there is $55.00 remaining in the fund for student dinners.
Dan was followed by Program Chair Sam Fielding-Russell, who reminded us that our last meeting before summer recess will be a week early: May 21st, because of the Memorial Day Holiday on May 28th. For that meeting our speaker will be Dr. Kevin Cavicchi, Assistant Professor of Polymer Engineering, the University of Akron, whose topic is announced above. Sam also reminded us that the he and Charlie Wilson had been soliciting the membership for potential subjects (and speakers) for next season, explaining that they had a reaped a plentiful harvest of suggestions. Now comes the task of finding speakers.
At this point Ernst turned the meeting over to Charlie Wilson “for certain unpleasantries he always performs at this time of year.”
“It’s election time again, folks!” Charlie announced, as he presented a totally unsurprising slate of officers for the coming year (which he claimed had represented a “spirited contest”):
|Chair||Ernst von Meerwall|
|Associate Secretary||Jerry Potts|
|Reservations Secretary||Charlie Wilson|
|Program Co-Chairs|| Sam Fielding-Russell
|Program Vice-Chair||Leon Marker|
|Name Tag “Marshall”||Milian France|
Charlie added that tonight we also had a Name Tag Vice-Marshall, Bob Erdman, who has been filling in during Millian’s absence (prompting Bob to interject, “It’s an honor to be Marshall of Vice”). Milian has been caring for Bill Jenkin, our 93-year-old member who, on this, the day of our meeting, had returned home from the hospice where he had been staying, obviously feeling better. (Bill had been in the hospital with pneumonia, where he had managed to also contract a debilitating c.dif virus.)
Charlie’s slate of (all continuing) officers prompted Chairman Ernst, following parliamentary procedure, to call for additional nominations, whereupon a deathlike silence descended on the room. Finally, hearing no motion of any sort, he asked whether he could assume that the slate was “accepted by acquiescence” whereupon, mocking parliamentary dogma, a single “yes” followed by a positive murmur, was taken as a vote of acclamation — a stunning victory for the present officers.
Which brought us, at last, to the introduction of our speaker for the evening, Dr. Narender P. Reddy, Professor of Biomedical Engineering at the University of Akron. who, having received a degree in mechanical engineering in India, earned a master’s at the University of Mississippi, and a PhD in biomedical engineering at Texas A & M. He went on to do a post-doc and the University of California School of Medicine at San Francisco. Because of the nature of his work, he is currently associated with Edwin Shaw hospital.
In announcing his talk in the Newsletter, we had abbreviated Dr. Reddy’s title to “Controlling Remote Robotic “Hands.” His original title, which more accurately describes the technology on which he has been working for more than a decade was: “Toward Direct Biocontrol of Virtual Environments Using Surface Electromyographic Signals.” His technology has made contributions in such diverse fields as aerospace, the nuclear industry, medicine, rehabilitation and even entertainment (i.e., games in which a dummy spear is thrown by an instrumented hand at virtual target on a monitor screen). Some of these applications represent environments in which human hands (or their attached people) might not survive; others, e.g., non-invasive surgery, environments in which human hands would be unwelcome (or may not be locally available!).
Current interface solutions for the remote operation of robotic “hands” include the Cyber Glove, Exo-Skeletal Devices, and other kinds of sensors that are externally worn by the operator. These are less than optimum for some applications and can be restrictive. Prof. Reddy has been working on systems which utilize skin-surface voltages (electromyographic signals) generated by the muscles of the remote operator. They represent systems which permit greater freedom and accuracy of both position and the amount of force applied by robotic “fingers” in the virtual environment. Some of our speaker’s applications include hybrid intelligence systems consisting of fuzzy logic and neural networks for dynamic control of virtual finger/wrist joint positions.
With the aid of a beautiful Power Point program (in which some words changed color as he spoke them), Dr. Reddy described some of the products of his work. We saw the positions in which electrodes were placed on the inside of the wrist and on the forearm of the operator just below the elbow. When needed, additional electrodes were placed on the back of the hand or on the backs of fingers. All of these sources pick up micro-voltages generated by the muscles; but when graphed on a screen, it is apparent that these are overwhelmed by other neural output, especially signals originating from the heart — of the kind that are routinely picked up by multiple sensors during electrocardiograms. The weaker signals from the operator’s hand and arm ride embedded in and on top of the cardiographic output.
The complex electronic solution is described in our speaker’s patent (5,482,051), “Electromyographic Virtual Reality System.” The patent details a computerized processing system in which the signals from the myographic sensors first enter an amplifier/ bandpass filter “which may, for example, pass signals in the 30 to 1000 Hz range” — excluding the intrusive signals. We saw these cleaned-up sine-like waves in Dr. Reddy’s Power Point images in comparison to the initial scrambled raw data.
The output from the filter is connected to a mean-square calculating circuit, which feeds a “look-up table” (in which the numerical value of the impressed force is displayed), as well as a “modeling engine” that provides feedback to the operator in the form of a visual display on a monitor screen or inside a head-mounted virtual reality helmet. A hydraulic force feedback unit provides pressure or other tactile feedback to the operator’s hand. Most of the actions we saw involved thumb and forefinger manipulation, but some involved wrist motion as well. The delay between operator signal and response of the remote fingers is only a few milliseconds, depending on the complexity of the action, while all of the resulting movements of the remote hand are monitored both visually and tactically.
Finally, we were shown a surgical scalpel instrumented with a strain gauge and an accelerometer and (as Bill Dunn explained to this writer after the meeting), a double integration of the root mean square of acceleration yields the position of the piece — a mathematical technique used in the aerospace industry for inertial navigation, using such double integration of acceleration input from a missile to determine its position in space. Dr. Reddy’s technology makes skilled surgery possible on a patient in a remote location by a surgeon a thousand miles away!
Meeting Announcement: May 21, 2007 - TANGIER, 6:00 PM
Our speaker for May will be Dr. Kevin Cavicchi, Assistant Professor of Polymer Engineering at the University of Akron, who will describe his work on
UNDERSTANDING THE DYNAMICS OF DIFFUSION
ORDERED BLOCK COPOLYMERS
(HOLOGRAMS - THERMODYNAMICS - MORPHOLOGY)
Minutes, May 21, 2007
Our last meeting before the summer recess began with a review of our wealth by Treasurer Dan Galehouse, from whose report it became apparent that the increase of a dollar for our meal expense has resulted in yet another increase in our club’s capital value. In a single month it has risen from $60.50 to a new balance of $73.60 (plus $55.00 in our fund for student dinners), obviously increasing our treasurer’s responsibilities over the summer (since no bank in town has been willing to accept an account of such insignificance).
And speaking of the intervening summer, Chairman Ernst von Meerwall announced that he will poll the club officers to choose a time for our annual executive luncheon to plan for the new season starting in September (all of which will have taken place by the time you read this in the fall) — all of which makes a somewhat awkward segway into Chairman Ernst’s calling on Program Chair Sam Fielding-Russell for a report on what we should be looking forward to in our new season. Sam noted that this was an easy up-date since he doesn’t know who our next speaker will be. BUT, he said the poll of the membership that he and Charlie Wilson had conducted, seeking potential subjects had yielded more than a dozen candidates, many of which have already been matched with possible speakers. Stay tuned.
The above announcements in combination with an obscenely delicious desert [consisting of double chocolate cake with strawberry and whipped cream appurtenances] brought us to the time for Chairman Ernst to introduce our speaker, Dr. Kevin Cavicchi, Assistant Professor of Polymer Engineering, the University of Akron, whose subject was Diffusion in Ordered Block Copolymers.
Accompanied by an excellent Power Point presentation, Dr. Cavicchi first showed us that a diblock copolymer consists of long strings of alternating, chemically dissimilar homopolymers covalently bonded together (AAAAA-BBBBB). When these are mixed in the melt these blocks tend to form tiny geometric nanostructures that take the shape of cylinders, cubes, spheres, or lamellar sheets — all of which inhibit mixing. Our speaker’s images demonstrated the dynamics involved in pulling an AAAAA chain out of one sphere or cylinder into an adjacent structure of BBBBB chains.
Dr. Cavicchi’s work has concentrated on evaluating the tracer diffusion coefficient (the chain mobility) of a variety of copolymers using a technique called “forced Raleigh scattering,” a holographic tracer grating technique that begins by chemically attaching a photosensitive dye to one of the polymers. To study the diffusion mechanism of a sample nanostructure, the melt is placed in a cell between glass plates, where it becomes the target of intersecting laser beams that create a diffraction grating.
The piece de resistance of our speaker’s graphics was a view of the apparatus he uses to evaluate the diffusion rate of a sample, in which these laser beams are readily apparent. We could see that an initial strong laser beam is split into two parts, which are directed left and right by mirrors around opposite sides of a rectangular pattern, before they are redirected at opposite diagonals so that they intersect in the sample encased in the cell. This imposes a regular holographic fringe pattern on the cell — one that is written into the polymer sample and which persists even after the laser pair is turned off. The pattern remains visible when just one (weaker) beam is turned back on. It degenerates with time; the hologram fades away as the molecules move about. The intensity of the first order diffraction pattern versus time yields a relaxation time which directly relates to the diffusion coefficient. Because the diffusion is very slow, and the measurement process can last for hours or even days, the technique constitutes a very sensitive method for evaluating the diffusion coefficient.
Kevin showed us the results of his team’s measurements of a variety of samples varying in molecular weight, the geometry of their nanostructures (sphere, square, cylinder), and ambient temperature, as well as of their grating spacings (which vary the intersection angle of the laser beams). His findings include the fact that the coefficient of diffusion varies directly with molecular weight. Although it is not chemically dependent. it can be influenced by the state of order vs. disorder of the polymer sample. It is extremely hindered in the ordered state. (Of course, the diffusion coefficient is not influenced by the fringe spacing of the diffraction gratings.) This relatively young technique should be useful to those engaged in polymeric research and development — especially in projects related to the fine-tuning of polymer properties for specific applications.
And for those who may have forgotten the poem by none other than John Updyke over the summer, I offer into our archives the lines that could serve as a motto engraved on the official seal for a club of our persuasion:
Neutrinos: They are very small,
And do not interact at all.
Meeting Announcement: MONDAY, September 24, 2007 - TANGIER, 6:00 PM
It is September already (!), signaling not only cooler weather at last, but the end of our club’s summer hiatus — and thanks to the efforts of Sam Fielding-Russell, Charlie Wilson, and others, we are in for some great programs.
For openers, we first had the pleasure of hearing molecular biologist Dr. Donna Galehouse, currently Director of the Molecular Diagnostics Laboratory at Akron’s Children Hospital. (As she explains, “the name has changed, but everyone here still thinks of it as the DNA Lab”). In 1994 she enlightened us on the subject of Molecular Biology: The Software that is Us. By the time we were able to coax her back in April of 2001, the science associated with her field had expanded to a point that permitted her to describe for us The Human Genome Project: How it was Accomplished and What does it Mean? This time her subject will be a welcome update:
THE HUMAN GENOME PROJECT
(MORE QUESTIONS THAN ANSWERS)
Previewing what else she plans to discuss, Donna says, “Now that the precise base pair order is known, what do we now know about how it works (how does it go about its job to make/define a unique human being)? If time permits I will include how this info is changing the practice of medicine.”
Minutes, September 24, 2007
Smiling smugly (with relief) after successfully performing his monthly ritual of mating our speaker’s laptop with the university’s Power Point projector, Chairman Ernst von Meerwall inquired whether our first meeting of the new season had attracted any new visitors. We had one, Wiley Young’s student, Khadiju Hindi. (We hope to see her again.) Ernst then called on Program Chair Sam Fielding-Russell, who is obviously assembling a great intellectual menu for us to feast upon during our 2007-8 season:
October 22: Charles Lavan
"Progress Report on the High Altitude Airship"
November 26: To be announced
January 28: Tim Mann
Schantz Organ Co. (Orville, Ohio)
"Physics & Construction of Large Concert Pipe Organs"
February 25: Dr. Amy Milsted,
Prof. of Biology, Univ. of Akron
April 28: Richard Goettler
Rolls Royce Fuel Cells
Solid Oxide Fuel Cells".
Because Treasurer Dan Galehouse has an evening class this semester, Kevin Cavicchi gallantly took on the considerable chore (this writer having tried it once and didn’t like it!) and subsequently provided a remarkable report: He took in $446 from 23 people at $19, and paid Tangier $408, then discovered a mysterious discrepancy of $9 in the club’s favor!
Kevin’s creative explanation: “Since no one demanded change at the end of the evening, I will attribute this to anonymous charitable donations from physics enthusiasts. This leaves $38 in profit. We had $74.60 in the bank at the start of the evening. We now have $112.60.” Pretty good for a first time effort!
It had then become time to introduce our speaker, molecular biologist Dr. Donna Galehouse, Director of the Molecular Diagnostics Laboratory at Akron’s Children’s Hospital. We first had the pleasure of hearing Donna in 1994, when she defined her field for us: Molecular Biology: The Software that is Us . By the time we were able to coax her back in April of 2001, the science associated with her field had expanded to a point that permitted her to describe The Human Genome Project: How it was Accomplished and What does it Mean?
This title of her September update on the subject was The Human Genome Project: More Questions than Answers. There are, it turns out, 3 X 109 base pair sequences in the human genome, 92% of which have been sequenced. The remaining 8%, our speaker explained, are nearly all the highly repetitive ones, some of which are repeated hundreds — even thousands — of times. The sequence is simply the order of components A, G, C, and T, which are joined by a hydrogen bond.
Experts believe that most, if not all, of the 20,000 protein-coding genes have been confirmed. The protein-coding DNA, she said, is the really interesting stuff: DNA replicates to form more DNA, that is transcribed into messenger RNA (which determines the order of splicing), that is translated into amino acids, which are sequenced for each protein. And it is now known that one gene can make multiple proteins.
But mutations — some caused by environmental factors, others by bacteria, are evidence that it doesn’t always work properly, e.g., causing red blood cells, which are ordinarily “shaped like a doughnut without a hole” to come out sickle-shaped, or worse, causing cystic fibrosis. There are, it turns out, diseases caused by single-gene mutations and multi-gene disorders. Some lead to cancer. But studying how these anomalies occur has helped researchers to understand the mechanism of the complex chemistry involved in causing a normal fertilized cell to turn into an embryo, an infant, a child, and finally an adult.
Each gene has a switch to turn it on or off — a promoter. These switches are specific DNA sequences right in front of the gene, which respond to specific signals. One of these that occurs in mammals that is very important in the development of higher organisms is the methylation of DNA sequences. Methylation changes the appearance and structure of DNA— making modifications that are stable over multiple rounds of cell division, but do not change the underlying DNA sequence. Researchers now have molecular methods that can distinguish methylated vs. unmethylated DNA.
The more detail Dr. Galehouse got into about her field (including the differing genetic contributions of the mother and the father), the more it became apparent that — as she had observed several times during her talk, “Life is not that simple.”
After the meeting, your secretary had the temerity to ask her whether she had any thoughts about the origin of this phenomenon we call “life.” Donna demurred.
Meeting Announcement: MONDAY, October 22, 2007 - TANGIER, 6:00 PM
In September, 2003, Charles Lavan, Engineer-Principal and Lead Scientist for Lockheed Martin, spoke to our club about The Future of Airships. A week later, his company was awarded a $40 million contract by the Missile Defense Agency for a stationary unmanned airship some 500 feet in length, which would operate on solar power at an altitude of 70,000 feet (a project our speaker’s company had been working on since 1998).
Two years later, in November of 2005, with a record attendance for our club, Mr. Lavan (now a Lockheed Fellow) gave us an update on the project. At that time we learned that the initial prototype would be built here in Akron, would be 430 ft long with a volume of 420,000 cu ft, operating at 60,000 ft, under autonomous control for 30 days at a time (although there is nothing to indicate that it couldn’t stay up for a year). The craft will be built in the Goodyear Airdock, and it will be big — taller than either the Akron or the Macon. Its four rotors will be the size of windmills, 25 ft in diameter, and they will be powered by a solar array half an acre in area, generating 100 kilowatts of power.
So: For our October meeting, we are delighted to announce that Charles Lavan will return to give us a
THE HIGH-ALTITUDE AIRSHIP
Minutes, October 22, 2007
The name of our speaker having turned out the multitudes, we had 32 members and guests at our October meeting, including first-timer Bob Brown, a guest of Bill Dunn (Bob has since asked to be put on the mailing list). Turning to future programs for the rest of the year, Chairman Ernst von Meerwall called on Program Committee member Bob Hirst, who announced that the subject for our November meeting, would be “Exploring the Surface of Mars,” one of the most popular requested subjects that had turned up in Charlie Wilson’s and Sam Fielding-Russell’s poll of the membership. Bob had contacted NASA, he said, making a request for a speaker on the subject, but did not have a name for us at this time.
Ernst then turned to Sam Fielding Russell for his report on the program schedule for rest of the year, which follows:
January 28: Tim Mann
Schantz Organ Co. (Orville, Ohio)
"Physics & Construction of Large Concert Pipe Organs"
February 25: Dr. Amy Milsted
Prof. of Biology, Univ. of Akron
March: To be announced
April 28: Richard Goettler
Rolls Royce Fuel Cell
“Solid Oxide Fuel Cells"
May 19 (Third Monday): Daniel Akerib
Case Western Reserve University
In a single item of business, Deputy Treasurer Kevin Cavicchi (Treasurer Dan Galehouse is teaching a class this fall) announced that we had begun the evening with a treasury balance of $112.60. After paying Tangier, we ended the evening with a grand, indeed, total of $155.60.) At this point one member, whose voice your secretary didn’t recognize on his tape (L) suggested that it would simplify everyone’s life (especially Kevin’s) if we changed the dinner price from the current $19 to an even $20, (even though this move would probably swell the treasury by several dollars, increasing the responsibility of Treasurer Galehouse over the summer). But Chairman Ernst opined that Tangier will probably make this change inevitable by spring whether we like it or not, and suggested that we leave it alone for the moment.
At which point, Chairman Ernst introduced our speaker, Lockheed-Martin Fellow Charles Lavan, who has been Engineer-Principal and Lead Scientist for Lockheed Martin on the company’s High-Altitude Airships project for the past decade. Having just heard that our speaker would be retiring in only 28 days, our leader expressed (faux) “dismay,” pointing out that our program committee had been counting on regular progress reports from him for years to come! But the upside to our speaker’s retirement announcement is that he asked to be put on the e-mailing list for our club’s Newsletter and monthly announcements; so, probably we’ll be seeing more of each other after all.
It was in September 2003, that Mr. Lavan spoke to our club about The Future of Airships. A week later (no cause -and effect-relationship so far as is known), his company was awarded a $40 million contract by the Missile Defense Agency for a stationary, unmanned airship some 500 feet in length, which would operate on solar power at an altitude of 70,000 feet — a project he and Lockheed had been working on since 1998).
Two years later, by now a Lockheed Fellow, Charles gave us an update on the project. We learned that the initial prototype will be built here in Akron, and that its tentative dimensions were a craft 430 ft long with a volume of 420,000 cubic feet. It would operate at 60,000 ft, under autonomous control for 30 days at a time (although there is nothing to indicate that it couldn’t stay up for a year or more) and that the craft will be built in the Goodyear Airdock. And, it will be big — taller than either the Akron or the Macon. Its four rotors will be the size of windmills: 25 feet in diameter; and they will be powered by a solar array half an acre in area, generating 100 kilowatts of power. In addition to driving the rotors, some of the power will be used to generate electrolytic hydrogen, which can replace any lost helium.
Our speaker began his talk this time with some of the “history of this little project I’ve been working on.” It all began, he said, in June of 1998, when he had a visit from General James Abramson, Director of the Strategic Defense Initiative. who had earlier reported directly to President Ronald Reagan on development of the Star Wars Program (which depended on reconnaissance satellites to sense ballistic missiles). General Abramson introduced the idea of a geo-stationary lighter-than-air craft that would hover at 65 to 70,000 feet — well above U.S. commercial or military aircraft (whose maximum altitude is limited to 53,000 feet — although some nations have a rarely-achieved 60,000 foot limit). He visualized the platform as a base for commercial communications as an improvement over satellites.
Lockheed took the idea to a little-known government agency called the National Reconnaissance Office, the group then in charge of building reconnaissance satellites. This NRO was intrigued with the idea. Under contract to the agency to investigate the feasibility of the idea, Lockheed showed that “the physics was there,” but that “the idea was a little more difficult than it sounds. You can’t just fill something with helium and let it go!”
As the ultimate design now stands, it will “just fit inside the Airdock. It will be bigger than either the Akron or the Macon,” which for those of us old enough to remember, were rigid craft the size of ocean liners — vastly larger than today’s Goodyear blimps (several of which could fit inside the Airdock). It will be launched here in Akron, and when it lifts off “it will blacken the skies . . . a solar eclipse!”
Because of the government’s interest in surveillance, the HAA (High Altitude Airship) Program now has several military sponsors; and it will also be a platform for commercial communications — something the Japanese have been pursuing vigorously. The Japanese have airships that hover at 50,000 feet. Lockheed has launched several experimental helium balloons to 60,000 feet, leaving them aloft overnight, communicating with them to record temperatures and other data.
The ultimate HAA airship will contain a volume of 5.5 million cubic feet of helium (Goodyear blimps hold 200 thousand cubic feet). But the current thinking is that starting with something a little smaller to learn on might be more prudent since, after all, “the Wright Brothers didn’t start with a 747.” So the first one launched will probably be about 400 feet long and 156 feet in diameter (blimps are 200 feet long and 50 feet in diameter, so the profile will be substantially different). The eventual full-size airship will be about 600 feet long and no more than 200 high, “Since the peak of the Airdock roof is 217 feet and we don’t want to build it and then wonder ‘how do we get it out?’”
The first geo-stationary vehicle will probably be dispatched to a location on the East Coast, where it will be commanded to go to 60,000 feet and stay there. It will have several missions, including weather (e.g. hurricanes in the Gulf of Mexico, which it will be well above), and its surveillance mission will cover of an area of about 1200 km in diameter — which can include the tracking of ocean shipping. It will also have a missile-defense mission. With only two or three ground controllers, it will be able to take the place of five AWAC airplanes, and since it has no internal combustion engines it is non-polluting. Its four 25-foot diameter variable-speed propellers are turned by variable-speed electric motors, which do all of the steering in addition to propulsion. In addition to the 6,000 lb of lithium-ion batteries (which are charged by its solar panels during the day), the airship will have a payload of about 500 lb and the availability of about 10 kw of power (at 70 volts DC). A later model, for a program called ISIS will have a payload of 7,000 lb.
The environment in which these craft will operate is unique. The air pressure is one twentieth of that at sea level; the temperature is –50 to minus –60 degrees C (materials have been selected that remain flexible at –90 degress C — a value that got the attention of this ex-rubber engineer!). An altitude of 65-70,000 feet is not only an environment where maximum ozone is generated, but may also be subject to vigorous vertical lightning, which originates at 80-90,000 feet above thunderstorms — a problem for the solid-state electronics.
To cope with the ambient ozone and ultraviolet, the skin is a six-layer laminate of ozone-resistant woven materials coated with PTDS. The internal “super-pressure ballonade” in the first craft will be filled at ambient Akron barometric pressure with about the same amount of helium as a blimp — about 200,000 cubic feet. The gas will expand to fill the airship as it rises to its 60,000-foot altitude in about an hour. The pressure in the ship at altitude will be so low (about 1.5 inches of water!) that a perforation will not be a problem, since it will be replaced by electrolytic hydrogen.
The first ship will be launched from Akron, probably in 2009. Because northern Ohio actually has the heaviest air traffic anywhere, the launch will be coordinated with air traffic controllers so pilots will not be surprised by this giant UFO.
The icing on Chuck’s exciting presentation was his suggestion that our club schedule a visit to the refurbished Airdock (redone to the tune of $40,000,000) where some smaller PTDS reconnaissance craft are being built to supplement those already aloft in Afghanistan and Iraq. These have do not engines, but are on tethers, some of which are on 5,000 ft long; others have a length of 15,000 ft.
Meeting Announcement: MONDAY, November 26, 2007 - TANGIER, 6:00 PM
Appropriately, while the Holmes Comet is still sailing overhead (at an “altitude” of 2.0 astronomic units), and at a time when NASA has just finished installing (and repairing) additions to the Space Station (at an altitude of 2.15 X 10-6 astronomical units), we will have a speaker from NASA. Since one of the most popular subjects resulting from the poll of the “membership” by Charlie Wilson and Sam Fielding-Russell was “exploring the surface of Mars,” we are delighted to announce a program by NASA’s
Dr. Geoffrey A. Landis, a researcher in the Photovoltaics and Space Environments branch at the John Glenn Research Center. It is:
A PHYSICIST ON MARS
THREE YEARS WITH
THE MARS EXPLORATION ROVERS MISSION
The Mars Exploration Rovers "Spirit" and "Opportunity" have now been exploring the surface of Mars for well over a thousand sols (solar days on Mars), ten times their nominal 90-sol design lifetime. This talk will discuss the Mars Exploration Rovers, present some of the results from the mission and how it's affected our current view of Mars, will discuss the continuing NASA program for robotic exploration of Mars into the next decade, and will look at the possibility of future human missions to Mars.
Minutes, November 26, 2007
Our last meeting of the year brought visitor Bryon Anderson to hear our NASA program on Mars exploration. Turning first to obviously complex club business, our Chairman Ernst von Meerwall explained that “although this is the customary time for the treasurer’s report, our treasurer has been replaced by another treasurer — who also couldn’t be here” — whereupon he presented good, old, reliable-for-any-chore Bob Erdman, who had stepped into the gap, collecting our cash for the dinner. After a round of deserved applause, Bob reported that the evening had resulted in a net profit of $8.00, swelling our treasury to $163.60!
Ernst then told us that the University is making some changes in its relationship with the Internet, and this may result in a change in the URL for the great website John Kirszenberg has built for the club [http://physics.uakron.edu/APC/news.htm]. During this period, in an effort to bypass any associated problems, in addition to the carrying the club hyperlink for the website, this monthly announcement will add the rest of the Newsletter — the minutes of the previous meeting (like this issue), which will also comply with a suggestion from several members who have admitted that while going through their e-mail, they sometimes put off taking the time to call up the website, and then rarely get back to it. We’ll see whether this mammoth e-mail is a popular idea.
Called upon by Ernst, Program Chair Sam Fielding-Russell reviewed our schedule for rest of the year:
January 28: Tim Mann
Schantz Organ Co. (Orville, Ohio)
"Physics & Construction of Large Concert Pipe Organs"
February 25: Dr. Amy Milsted
Prof. of Biology, Univ. of Akron
March 24: Dr. Bryon Anderson
Prof. Of Physics, Kent State University
“The Electric Form Factor of the Neutron”
April 28: Richard Goettler
Rolls Royce Fuel Cell “Solid Oxide Fuel Cells"
May 19 (Third Monday): Daniel Akerib
Case Western Reserve University
Which brought our chairman to the introduction of our speaker, Dr. Geoffrey Landis, NASA scientist, from whom we were last privileged to hear in September of 2000. With degrees in physics and electrical engineering from MIT and a PhD from Brown University in solid-state physics, Dr. Landis has published more than 300 scientific papers, and is also the author of 70-some works of science fiction — for one of which he received the Hugo Award. The title of his talk for our last meeting of the year was A Physicist on Mars: Three Years with the Mars Rovers Mission.
His talk underscored by magnificent Power Point images he has collected over the years, our speaker began by showing us Mars’ position in the solar system, comparing its size and geography with that of other planets. He pointed out that although Mars is smaller than the Earth, the fact that our planet is three-quarters water, Mars’ land area is about the same as that of the Earth, and is even more diverse. It is studded with enormous volcanoes, giant canyons, and polar ice caps that change in size with the seasons, and where the temperature at times drops below 145 degrees Kelvin. Even from the Hubble telescope we could see that it has atmosphere, it has climate, it has weather, albeit with “air” a hundredth the density of ours. Nevertheless, we later saw close-ups of Texas-type “dust devils” on the surface and later an early morning fog and even a dust storm. But there was zero evidence of Percival Lowell’s 1908 “canals,” which inspired a generation of science-fiction writers.
We saw how the orthodox view about Mars geology has changed with sequential views from the Viking orbiter, the Pathfinder vehicles, as well as in the subsequent Rover missions (in some of which we rode along in movies projected on the screen). It was apparent that although there is no water on the surface of Mars, it is not a Moon-like desert surface. Instead, there is evidence of dry riverbeds with tributary branches, some having actually cut canyons. NASA’s strategy for missions subsequent to Pathfinder has, consequently, been “Follow the water — understanding the history and geology of water is the key to understanding Mars.”
A launch to the other side of the planet landed in a crater about 5 meters in diameter (“a hole in one from a 100 million miles”). This turned out to be a great choice, since the crater had blasted through the surface, exposing layered sedimentary rock — a great find for the NASA geologists interested in the action of water. Dr. Landis showed us “stretched [enhanced] color” views of the rock layers in 13 colors (produced by 8 different filters, some of which leaned into the infrared). Lying on the surface, just sitting there, we saw a nickel-iron meteorite, and, thanks to the vehicle’s robotic arm, a grinding tool and a spectrometer along with other instruments inside the Rover, we learned that it is 95% iron, 5% nickel, with traces of cobalt. Other sample results turned up a variety of elements: sulfur, chlorine, bromine, zinc, nickel, and iron.
Although the Rovers were designed to last a Martian summer, their life extended through the winter and then some, so the team had to design some new experiments — so they headed for the hills — from which we saw a view of Victoria crater from 50 miles away (looking like a giant asterisk), many other craters, an earthrise, and a Martian sunset. (Due to differences in the scattering of sunlight, in contrast to blue skies on Earth, which turn red at sunset, Martian skies are normally red, turning blue at sunset.) The stunning slide show went on for nearly an hour, including views of future lander vehicles and their instruments. Those who were unable to make the meeting can see some samples at https://pds.jpl.nasa.gov as well as at https://pds.jpl.nasa.gov/planets. A conclusion one can draw is that Mars is not the “red planet” except for broken-open hematite. In truth, Mars is the Butterscotch Planet.
And if you care to provide some feedback on the reception (and/or desirability) of including this much material in the monthly announcement/Newsletter, I’d appreciate hearing from you.