Accelerating Photosynthesis Using Electro-Mechanical Means

ABSTRACT:
This accelerated photosynthesis system takes advantage of Nature’s own way of maximizing rapid plant cell growth, with emphasis on growing food plants. It does not involve the use of chemicals applied to plants, nor does it involve any type of genetic alteration.
As is well-known, millions of people throughout the world are starving because of food shortages caused by flood, famine, poverty, politics, and indifference.
I am donating and publicizing this concept of accelerated photosynthesis, for anyone to copy, in the interests not only of mitigating worldwide food shortages, but also in the interests of replenishing and maintaining the world’s supply of oxygen.
From a environmental viewpoint, accelerated photosynthesis could be used to grow more green algal cells to use up excess atmospheric carbon dioxide, in order to make oxygen. Currently, carbon dioxide is well above the 250 parts per million considered a safe maximum for the planet.
A green algal cell, for example, can produce oxygen up to thirty times its volume in an hour, every hour, given sufficient light and carbon dioxide. Normal concentration of Earth’s atmospheric oxygen is about 20 percent. Should that fall below 17 percent, we would be gasping for breath, as was proven in the 1990s Biosphere project in Arizona. Reportedly, the U.S. generates only 62 percent of the oxygen that it consumes. The shortfall is made up by the winds from other sources around the world.
The ultimate goal, then, is rapid, maximum yield of food, and oxygen-producing algal cells.

ARTICLE TEXT:
Accelerated Plant Photosynthesis by Electro-Mechanical Means
James Garden, Jr.
Copyright © 2009
Copyright © 2011
Reproduced by permission
This accelerated photosynthesis system takes advantage of Nature’s own way of maximizing rapid plant cell growth, with emphasis on growing food plants. It does not involve the use of chemicals applied to plants, nor does it involve any type of genetic alteration.
As is well-known, millions of people throughout the world are starving because of food shortages caused by flood, famine, poverty, politics, and indifference.
I am donating and publicizing this concept of accelerated photosynthesis, for anyone to copy, in the interests not only of mitigating worldwide food shortages, but also in the interests of replenishing and maintaining the world’s supply of oxygen.
From a environmental viewpoint, accelerated photosynthesis could be used to grow more green algal cells to use up excess atmospheric carbon dioxide, in order to make oxygen. Currently, carbon dioxide is well above the 250 parts per million considered a safe maximum for the planet.
A green algal cell, for example, can produce oxygen up to thirty times its volume in an hour, every hour, given sufficient light and carbon dioxide. Normal concentration of Earth’s atmospheric oxygen is about 20 percent. Should that fall below 17 percent, we would be gasping for breath, as was proven in the 1990s Biosphere project in Arizona. Reportedly, the U.S. generates only 62 percent of the oxygen that it consumes. The shortfall is made up by the winds from other sources around the world.
The ultimate goal, then, is rapid, maximum yield of food, and oxygen-producing algal cells.
Although there are approximately 2.5 million acres under greenhouse roofs worldwide, this accelerated photosynthesis concept does not necessarily require a greenhouse—it can be accomplished in any structure, like a dark room, where abundant sunlight can be piped in, and greenhouse systems can be installed. Dark room requirements will be enumerated later. For now, assume that a properly-designed and properly operated greenhouse is being used. Possibilities for future open-field planting also will be discussed.
Literally, photosynthesis means: “to build with light”. Without the process of photosynthesis, there would be no life as we know it.
The rate at which photosynthesis takes place depends upon many well-known factors, among which are the concentration of carbon dioxide; the wavelengths (color) of light received by plants; the intensity of that light; ambient air and soil temperatures; the availability of plant nutrients; and the age and physiological condition of the plants1, all of which can be controlled within a building.
Carbon dioxide concentration in the Earth’s atmosphere during the Carboniferous Period of the Earth’s history was much higher than it is currently, which excess carbon dioxide helped to account for the superabundance of land-based plant life at that time.
Blue and red wavelengths have the energy needed to elevate chlorophyll electrons to the higher energy levels needed during the chemical reactions that take place during the entire complex process of photosynthesis.
During the process of photosynthesis, plants need a period of time for exposure to light, and a period of rest—a period of darkness that is longer than that of the light exposure period—to complete the chemical reactions that convert sunlight, water, and carbon dioxide into carbohydrates and oxygen, using chlorophyll and enzymes.
Maximum plant growth rate through photosynthesis can be achieved by subjecting the plants to alternating periods of light and dark—specifically—light duration of 1/100,000th of a second followed by a dark period of 1/100th of a second duration2—the dark period being one thousand times longer than the light exposure period. This means that plants will be in a dark environment 99.9% of the time. Of course, light exposure periods longer than 1/100,000th of a second, and dark periods longer than 1/100th of a second will accelerate photosynthesis, but not at its maximum rate. The most basic and least expensive system is discussed first. It requires only one moving part.
Electromechanical Systems
Electromechanical systems can be engineered in many ways to provide accurately-timed, alternating light and dark periods, taking advantage of both sunlight and electrical lighting.
It is mandatory for this first-described configuration that intense sunlight can be directed into the center of the greenhouse or dark room, and be excluded everywhere else. In a greenhouse, this requirement means that plants will be shielded from greenhouse overhead daylight with temporary or movable light-proof covering.
At the geographic center of the room is an empty, ten-foot-diameter [3 meter] access circle. A five-foot-wide [1.5 meters] paved walkway leads to the circle from a service entrance to the room.
In the center of the circle is a permanently-mounted, one-foot diameter vertical pipe, about four to six feet high, that can be telescoped downward into a recess in the ground. The top of the pipe contains a stationary, round light chamber constructed to receive both piped-in sunlight and/or electric lighting from the pipe space directly below the light chamber. A laser emitting the proper wavelengths would be an ideal source of artificial light. The telescoping feature will enable the light chamber’s height to be adjusted up or down as needed.
Surrounding the round, stationary light chamber is a rotating device, continuously rotated by an electric motor, and equipped with optical devices whose purpose is to continuously project intense, narrow beams of light throughout the full 360 degrees of rotation at 20 rotations per second, which, of course, is 1200 revolutions per minute.
For experimental purposes, only two mirrors, one glass fiber unit, and one rotating light, would be needed to test the concept. The mirrors and glass fiber unit will be described below.
With reference to the horizontal plane of the rotating device, the optical device can have a maximum of five, horizontally-mounted optical projection lenses spaced 72 degrees apart, as measured from the center axis. There may be a minimum of one horizontally-mounted projection lens, with the option of having two, three, and four projection lenses added later. The reason for these multiple options will be explained below during the discussion of light-beam timing.
The space below the light chamber receives the piped-in sunlight, and at night can receive light from electric lights or lasers. Both sources of light, of course, illuminate the stationary light chamber.
Rows of seedling vegetable or other plants radiate outward, beginning at the edge of the ten-foot circle located at the center of the dark room. The rows radiate outward at five-degree increments of separation, as measured from the center of the circle. A total of seventy-two rows are possible, but four rows must be eliminated in order to provide for an access path. At the periphery of the ten-foot-diameter access circle, where the rows of plants begin to diverge from each other, the rows are approximately one foot apart.
Hanging beneath a suspended, movable framework directly above the plants and parallel to the rows are translucent plastic pipes of about three-inch diameter, the top half of said pipes to be of parabolic cross-section, and the inside of the top half is to have a highly reflective or mirror-like coating to reflect the light which will be sent into the pipes. An alternative to the translucent plastic pipes would be optical fiber cables that are sheathed with a transparent casing.
The purpose of the plastic pipes, or the optical fiber cables, is to illuminate only the plants beneath them by a precisely-timed light beam from the centrally-located light source in the dark room. Rows of plants are separated from adjacent rows by hanging black plastic curtains that shield each row of plants from stray light that might come from adjacent rows.
If a dark room is to be used for growing vegetables from seed to mature plants, the floor of the room is to be covered with about two to three feet of sterilized soil or other sterilized growing medium. Microbes, worms, and other beneficial living organisms can be added after the soil is sterilized.
Beneath the surface of the soil or growing medium is a net-like system of plastic tubes to be used for underground watering of plant roots. The plastic tubing can be made in long, parallel lines, all of which would be connected to a manifold at one end, and sealed at the other end. If a net-like system is required, then two systems of straight tubing can be laid at right angles to each other.
Such watering can be done using DuPont plastic tubing such as is used in their reverse-osmosis systems. Pore sizes can be adjusted from 1 to 5,000 nanometers, depending on plant requirements. It is important that the tubing be of the osmosis type, where water pressure can be maintained more or less equally throughout the length of the tubing.
Tubing with comparatively large holes will not only not maintain uniform water pressure throughout its length, but water expelled as pressurized streams may hollow out air or water pockets near plant roots, killing the plants.
Underground irrigation can permit the savings of up to 75% of the water now used for surface irrigation. Moreover, water vapor expelled by plant transpiration can be recovered at night by recovering condensation on the underside of a greenhouse glass ceiling. By day, dehumidifiers can control greenhouse humidity—any condensed water to be recycled.
Fertilizers in true solutions can be introduced into the underground irrigation systems, or separate underground feeding systems can be used.
If seedlings in peat moss containers are to be started in the dark room, and then transplanted later, then an above-ground drip-type watering system must be used. The seedling plants are arranged in straight, single-file rows radiating out from the ten-foot diameter center.
At a given radius from the rotating device, [50 feet in this description], the rotating projected light beam would successively strike two [2] side-by-side mirrors, A and C, for each radiating row of plastic pipe or transparent optical fiber cables. Each mirror would be small, stationary, flat, front-surfaced, facing the light source, and would be mounted downward from the vertical at 45 degrees.
To avoid confusion, a front-surfaced mirror is one that has the reflecting silver in front of the glass supporting the silver coating, so that light is reflected by the silver coating first, without going through the glass before reflecting the light. Each mirror is mounted at the same height as the light beam, and is located directly above each row of the plastic pipes or the bundled glass fibers, which are mounted directly above the plants.
The mirrors can be attached to the suspended, movable framework mentioned earlier. That framework can be raised up high enough to allow people to inspect or to harvest the crop being grown. During the growing time, the framework is rigidly fixed and aligned to insure that the mirrors properly reflect the intense light beams downward towards the mechanism that diverts the light beam to the plastic pipes or to the bundled fibers.
Upon striking front-surfaced mirror A, the rotating light beam would be reflected downward to another front-surfaced mirror, mirror B, fixed at a 45 degree angle that is oriented to direct the light back towards the center of the circle. In this way, each plastic pipe is illuminated from that point to the center of the circle. If transparent optical cables are used, the light reflected downward from mirror A is focused directly at the end of the cable, and provides illumination to the plants directly under the transparent optical cable from that point to the center of the circle.
When the light beam strikes adjacent mirror C, the light beam, directed downward, is reflected by front-surfaced mirror D, fixed at 45 degrees and oriented away from the center of the circle, and illuminates plants in a straight line leading away from that point, and towards the end of that row. If transparent optical cables are used, the light reflected downward from mirror C is focused directly at the end of the cable, and provides illumination to the plants directly under the transparent optical cable from that point to the end of the row and away from the center circle.
The transparent sheathing of the glass fibers—[not the individual fibers]—is to be coated on the upper surfaces with a reflective coating, in order to direct the light downward to seedling plants below the illuminated glass fibers, and not illuminate anything above the bundles.
Black plastic sheeting or other opaque material is to be mounted high enough between each row of plants to prevent light spillage to other rows, and to confine the light and dark period timing to their intended rows.
The advantage of this configuration of light fibers is that all of the plants—the nearest and the farthest from the light source, would receive exactly the same timing of light and dark periods, as the light beam from the rotating pipe sweeps around, hitting each of the individual flat front-surface mirrors.
Obviously, if the plants were illuminated simply by a rotating beam of light, the timing of the light phase would be such that the plants nearest the light would receive a higher intensity of light and at a slower rate than plants farther out from the light source. The dark phase would be similarly affected also.
As the rows of plants radiate out from the center, the spaces between adjacent rows get wider, making room to start new radial rows of plants so as not to waste space. The new rows would be built exactly as the original columns, but could be lighted in two different ways: either by bleeding off light from the existing bundled glass fibers while they continue to illuminate all of the original bundled glass fibers and without adding new mirrors for the new rows, or, build a new ring of reflecting mirrors farther back than the original ring to service the new bundled glass fibers, and mount them higher than the original ring of mirrors.
The addition of new rows would necessitate the inclusion of two light beams on the same central vertical pipe if a new ring of reflecting mirrors were to be installed—the new ring higher than the original. The second light beam would be mounted higher than the original light source; it would have an independent axis within the axis of the original light source; and its timing would be adjusted independently to accommodate the longer [longer distance, longer timing] sweep of the higher light beam.
Wavelengths and intensity of light necessarily would be controlled as needed before the light is routed through the rotating optics.
Light boosters, the same as is used for fiber optic communication systems, can be placed where needed to maintain a uniform intensity of light where long rows of bundled glass fibers are used for providing light to the plants.
The farther the reflecting mirrors are from the rotating light source, the faster the light beam travels around the periphery of the described circle, and, within limits, the slower the required rotation speed of the light source would need to be. Anyone who has been at sea knows how fast the sweep of a lighthouse beam increases as one sails farther from the light..
As many mirror/glass fiber units as possible would be placed adjacent to each other around the chosen circumference, illuminating as many plants as possible. A circle
with a diameter of 100 feet would allow the processing of approximately 123,000 seedlings (using 3x3-inch peat moss transplantable containers), while allowing for the central area of ten feet diameter for positioning and servicing the rotating pipe, plus an aisle to access the pipe.
Controlled and elevated concentrations of carbon dioxide, and temperatures elevated to a plant’s optimum heat tolerance, easily can be added to the environment in a greenhouse or dark building to provide ancillary means of accelerating plant growth.
Cautions, obviously, must be taken to protect people in such an environment. High concentrations of carbon dioxide are as deadly as carbon monoxide. Of course, persons that must work in the structure during a state of elevated carbon dioxide must wear proper breathing apparatus. Temperatures of 120 degrees F. combined with humidity at 97% are enough to burn the inside of one’s lungs.
Throughout the growing season¬s, the concentration of carbon dioxide can be regulated in a dark building or greenhouse. Oxygen given off by the plants must be dispersed in order to make room for the heavier carbon dioxide required by the plants.
When it is time for pollination, bees and other pollinating insects can be introduced into the dark building or greenhouse after carbon dioxide levels have been adjusted The lights may have to be on throughout the pollination period.
Bees and their hives could be housed in a structure adjacent to the greenhouse or dark room, where flowers would provide pollen before, during, and after the pollination period of the food plants.
Unwanted insects and animals, wind, rain, edaphic growth conditions, soil erosion and poor growing conditions would be minimal factors in the automated dark building or greenhouse. Care, of course, must be take to prevent the introduction of deadly diseases into the plants.
If a greenhouse is not available, then a large, windowless structure with a one-level room and a dirt floor is necessary, if a vegetable crop is to be grown from seed germination to the mature plant. If seedlings are to be started in peat moss containers, and transplanted later, then a dirt floor or a paved floor will suffice.
It is mandatory that intense sunlight can be directed into the center of the room. The dark room can be in the basement or the top floor of a commercial building, in a purpose-built structure, or even in a large cave.
The advantage of a year-round growing season of growing multiple crops under controlled conditions will more than repay the cost of the initial greenhouse/dark house investment.
Calculating Rotating Light Exposure Periods
With a light-swept diameter of 100 feet, the vertical light pipe would need to rotate 1200 revolutions per minute (RPMs) to illuminate a 0.75396-inch-wide individual
flat mirror for each row of bundled glass fibers for 1/100,000th of a second. The mirror lengths should be at least equal to its width, and should be long enough to contain the entire periphery of the light beam.
Twelve-hundred revolutions per minute translates to 20 revolutions per second, therefore, the dark periods for each set of plants beneath each row of illuminated glass
fibers would be approximately 1/20th of a second. Each mirror, no matter how close to or far apart from each other, would be illuminated only once per light beam revolution.
The calculations for the width of the reflecting mirrors were arrived at as follows:
At 20 revolutions per second, the light swept in one second would be equivalent to 20 times the circumference of the 100-foot circle. Using the quantity of pi as 3.1415, the circumference is calculated as 314.15 feet, or 3,769.8 inches. Twenty times 3,769.8 equals 75,396 inches that would be swept in one second. That figure, divided by 100,000 equals 0.75396 inches—the amount swept by the light in 1/100,000th of a second—and that determined the minimum width of the flat front-surface reflecting mirror.
At pipe rotation speed of 2,400 RPMs, or 40 revolutions per second, the flat mirrors, (and the light beams), could be 1.50792 inches wide. Twice the rotation speed equals twice the distance the light beam travels in 1/100,000th of a second. The dark period would be ≈1/40th of a second.
For pipe rotation speed at 3,600 RPMs, mirror width would be 2.26 inches, and the dark period would be ≈1/60th of a second. For 4,800 RPMs, a mirror width of 3.0016 inches, and a dark period of ≈1/80th of a second would be attained. At 6,000 RPMs, mirror width could be 3.77 inches, with a dark period of ≈1/100th second.
Even at 6,000 RPMs. the small-diameter rotating light pipe or pipes would not generate large centrifugal forces or momentum.
At twelve-hundred RPMs, 1/100th of a second dark period could be accomplished by having five projection lenses mounted on the light rotation mechanism, spaced 72 degrees apart. We have seen that at 1200 RPMs, the dark period using one light projection lens or one laser, sweeping one full rotation, is 1/20th of a second.
By using five projection lenses or lasers spaced at 72 degrees apart, the dark interval becomes 1/100th of a second—1/5 times 1/20 equals 1/100.
The system does not have to operate at maximum speed. The rotation speed of the light beam determines the duration time of the dark period. As we have seen, twenty rotations per second establishes a dark period of 1/20th of a second. Forty rotations per second provide a dark period of 1/40th of a second, and so on for other rates of rotation.
The width of the front-surface mirrors that deflect the light beam to the light tubes or the optical fibers, determines the duration of the light exposure period. At twenty light-beam-rotations per second, it was determined that a mirror width of 0.75396 inches would provide light exposure of 1/100,000th of a second to the plants. Doubling the mirror width to 1.50792 inched would double the light exposure to 1/50,000th of a second, and so on for other rates of light rotation and mirror widths.
The flexibility of altering the durations of the light periods and the dark periods lends itself to experimentation in order to determine optimum periods of light exposure, and non-light exposure.
Once built, this system would be very easy to maintain. It would have only two moving parts—the light source and an electric motor to rotate the light. Less complicated means less maintenance and less overall costs.
The proposed mechanical systems described above involve high speeds to obtain the maximum rate of photosynthesis, and thereby, the maximum rate of plant growth. Operating the mechanical systems at lower speeds would, nevertheless, exceed greatly the rate of plant growth found in nature.
Electronic Systems
In the future, it may be possible to control greenhouse light and dark periods with electrochromatic glass. At a minimum, electrochromatic glass should meet the following specifications:
1. The glass must be completely transparent when energized, and 100% opaque when not energized.
2. The glass must be capable, when energized and under the control of computers or other electronic devices, to become fully transparent for 1/100,000th of a second, followed by a non-energized dark period of 1/100th of a second. The 1/100th of a second dark period may be used to prepare for the next 1/100,000th of a second light period.
3. The light and dark alternating sequence in 2 above must be repeated continuously during daylight hours, or 24/7 if using daylight and artificial light of the proper wavelengths.
4. The glass must not require excessive amounts of electricity. Electricity provided by or augmented by solar panels would be ideal for daylight hours.
5. The glass must be available in sizes of one-foot square and larger.
6. Its cost must not be prohibitive.
Other electronic methods may include the use of electro-optical devices such as Pockels cells and the use of “Q-switching”. Pockels cells have been developed with apertures as large as 150mm. Q-switching3 can generate nanosecond electric pulses.
Although Pockels cells and Q-switching may be expensive, they may afford the opportunity to test growth rates in the laboratory, using the optimum short light and dark periods of light noted above.
Laser pulses of four femtoseconds (four million billionths of a second) have been achieved4 attesting to the fact that mature technology does exist to provide the short-duration lighting required for photosynthesis to achieve maximum plant growth.
Micropower impulse radar (MIR) is an ultra-short-range radar system small enough to be put on a $10 computer chip, using very little electricity. The MIR device can send out short-range signals in a matter of nanoseconds, so it may be able to be adapted to control the light and dark periods when using artificial lighting at night. MIR was invented in 1992 at the U.S. Lawrence Livermore National Laboratory5. See wwweng.llnl.gov/mir_home.html
The MIR impulse radar also has another potential use—the excitation of argon gas and a small amount of sulfur in a light bulb—to make extremely intense light which is relatively free of ultraviolet wavelengths.
Some years ago, Fusion Lighting of Rockville, Maryland, developed a light bulb the size of a golf ball under a U.S. Department of Energy grant. Inside, the bulb was filled with argon gas, and a small amount of sulfur. There was no filament to burn out, as in incandescent light bulbs. Intense light—450,000 lumens—was created when the bulb was subjected to micro waves. By comparison, a 100 watt incandescent light bulb generates 1690 lumens.
Another configuration would eliminate the rotating light and the reflecting front surface mirrors. Instead, a light-proof wall surrounding the ten-foot diameter would be built. The ends of bundles of optic fibers above each radiating row of plants would protrude through the light-proof wall about an inch. Several Fusion light bulbs would be mounted such that when electricity was turned on at night by timing devices, the Fusion light bulbs would illuminate the ends of the protruding optic fibers. Sunlight would be directed to the optic fibers during daylight. The optic fibers would carry the light to the plants in all of the rows all at the same time.
The timing of the lights would be determined by experimentation.
Microwaves generating 450,000 lumens from the Fusion light bulb would create much heat. Less powerful microwaves, such as those developed by the MIR system, would generate less heat and less lumens, but still would be bright enough for the task.
Alternatively, the heat given off by Fusion light bulbs when subjected to powerful microwaves could be used to heat or to help heat greenhouses in cold weather where this light and dark system of accelerating photosynthesis is used.
A heat pipe can conduct quantities of heat thousands of times more (and faster) than solid metal rods of identical size, therefore, heat from Fusion light bulbs can be directed by heat pipes where and as needed.
An alternative to the Fusion light bulb is a light-emitting diode (LED) light bulb, which is 70% more efficient than an incandescent light bulb. LED bulbs use much less electric power while developing the same amount of lumens that incandescent bulbs of the same rating develop. LED light bulbs hardly ever burn out—life spans of 60,000 hours (6.87 years) and more have been attained. Obtaining LED light bulbs of the proper wavelengths should present no problem. The timing for light and dark periods could be computer controlled, incorporating MIR or other electronic devices as a switch activator, into the system.
Other lighting alternatives would include current commercial mercury vapor lights into which scandium iodide has been added, resulting in a light very close to natural sunlight6.
A concept remains a concept unless and until it is successfully implemented. There can be no implementation without a pre-existing concept, giving rise to an intrinsic relationship between concept and implementation.. This author has provided the concepts and has suggested various means of implementing them.
Growing plants at their maximum rate can yield valuable insights into the complex chemical reactions that take place during photosynthesis and plant growth.
Until it is possible to grow plants at their maximum rate, it is possible now to grow them at accelerated rates in greenhouses. Instead of 1/100,000th of a second of light
exposure, followed by a dark period of 1/100th of a second, for example, 1/1000th of a second light exposure followed by a full second of darkness certainly is attainable, using either the electronic or the electromechanical methods described above. Light exposure of 1/10,000th of a second is not beyond reach, followed by a dark period of 1/10th of a second.
Parallel furrows in open farm fields could be sown with vegetable plant seeds, then covered with lightweight opaque material that is self-supporting, or is mechanically supported a height that would be appropriate for mature plants. Lighting of bundled optic fibers mounted above the plants along all the furrows would be synchronized to illuminate all of the plants at the same time, providing the optimum light and dark periods for the particular plants being grown. This method would have few of the controls available in a dark room or greenhouse, but it would be the least expensive way of growing vegetables at accelerated photosynthesis rates.
Electrochromatic glass with the required timing of light and dark periods will be available in the not too distant future to enclose greenhouses.
Some farms of the future could have furrows under electrochromatic glass growing two to five crops per year, summer and winter. The entire area under glass would be automated. Not only will light exposure be regulated, but also water, humidity, plant nutrition, carbon dioxide concentration, insect pollination, and greenhouse temperature.
Hopefully, electrochromatic glass eventually will be powered by solar means, and will become cheap enough to completely cover plants in plowed fields with rows and columns of electrochromatic glass in the shape of arched tunnels made high enough to allow plants to grow to their mature height. Underground watering methods would be needed. Provision would be made to vent heat build-up beneath the electrochromatic glass. The glass could be made to reflect much of the radiant heat. Keep in mind that the plants beneath the glass would be in the dark more than ninety-nine percent of the time.



References

1. The McGraw-Hill Encyclopedia of Science and Technology, 9th edition, © 2002
2. The Harper Encyclopedia of Science, second edition, © 1967, pages 919-920.
3. Encyclopedia of Laser Physics and Technology, ©2008, Wiley-VCH.
4 “Nature’s Building Blocks, An A-Z Guide to the Elements”, by Dr. John Emsley
Oxford University Press, © 2002, page 456.
5. Lawrence Livermore National Laboratory
P. O. Box 808, L-795
Livermore, CA 94551
Website for MIR: www-eng.llnl.gov/mir_home.html
6. “Nature’s Building Blocks, An A-Z Guide to the Elements”, by Dr. John Emsley
Oxford University Press, © 2002, page 378.