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Microcap & Penny Stocks : RHOMBIC CORP.(NUKE.Nasdaq BB) Daimler Benz Aerospace JV -- Ignore unavailable to you. Want to Upgrade?

To: Chuca Marsh who wrote (1240)	8/11/1999 10:24:00 AM
From: Chuca Marsh	Respond to of 1364

I seached the two words on METACRAWLER built into S.I./ GO2 Network here at Techstocks. Lycos had many referances to a dramatic change that will affect a Billions Dollars Industry that WILL be ( in the FUTURE) ...developing. Here is a partial source referance to that search, it will change everything we can imagine. The seached was [rompted by a thirst for more information. The CHIP tech of Rhombic is documented to make a better HOTTER ( 4-5 fold) higher run temp application with our Diamond TECH! Yes. I see that and I see parts of these pieces and fragments in the future. I think I actually got this ASSIGNMENT...because that was my first question to RHOMBIC IR in the first phone call, can it be cooler/ hoter, could be! SUPPERCONDUCTIVITY is a NEWTECH, start to a change in all electronics, ONE must have a specific application...to suceed fast and cheaper, IMHO; NUKE has one: SEC DISCLOSURE for I.R. Assistance on my P.P. non members may read the thread in mid june on for posted specifus. ( Of the 20K options that strike in 1-1-200 at 50 cents first in THE RIGHT tpo purchase stock, no payday untill that event, thru that positive appreciation of the stock of Rhombic EVENT! Ie I am not really PAID now, maybe in Y2K) fysik.lu.se RE: Lycos search: superconductor high temperature Load average: 0.06: Lycos Apr 24, 1995 small catalog, 505407 unique URLs (see Lycos News) -------------------------------------------------------------------------------- You can search this index. Type the keyword(s) you want to search for: -------------------------------------------------------------------------------- Found 11591 documents matching at least one search term. Printing only the first 10 of 11519 documents with at least scores of 0.010. Matching words (number of documents): superconductor (63), superconductorr (1), superconductors (127), high (10281), higha (1), highacre (1), highaddrs (1), highadventure (3), highalpha (12), highalphaiv (13), higham (28), highamer (1), highamlisa (1), highands (1), highate (1), highback (3), highball (8), highballs (3), highband (6), highbank (1), highbanking (1), highbanks (1), highbanner (2), highbaugh (1), highbay (2), highbcv (2), highbeams (1), highbic (1), highbinder (1), highbit (4), highbltn (1), highbnr (1), highbo (1), highbook (1), highborn (2), highbowl (1), highboy (3), highbridge (1), highbrow (9), highbrows (2), highbury (20), highbutn (1), highbyte (1), highc (24), highchair (1), temperature (1265), temperature7 (1), temperaturecolours (1) -------------------------------------------------------------------------------- ID484085: [score 1.0000, 3 of 3 terms, adj 1.0] uq.oz.au date: 22-Apr-95 bytes: 1312 links: 3 outline: Superconductor Precursors and Powders keys: superconductor superconductors temperature excerpt: Superconductor Precursors and Powders SEM of 2223 Precursor SEM of 2223 Powder SEM of 2223 High Temperature Superconductor SEM of Y-123 Powder TEM of Y-123 High Temperature Superconductor TEM of Y-123 Clean Grain Boundary Superconductor Targets and Wires High Temperature descriptions: Superconductor Precursors and Powders -------------------------------------------------------------------------------- ID484082: [score 0.9710, 3 of 3 terms, adj 1.0] uq.oz.au date: 22-Apr-95 bytes: 2336 links: 3 outline: High Temperature Superconductors keys: superconductor superconductors excerpt: High Temperature Superconductors The Centre for Microscopy and Microanalysis, in collaboration with the Department of Mining and Metallurgical Engineering, both at The University of Queensland, established a research and development team in superconducting ceramics in 1991. This team was formed through a multi-million dollar contract from the University's Syndicated Research and Development Program and incorporates an important maxim: high quality ceramics processing -------------------------------------------------------------------------------- ID296344: [score 0.9654, 3 of 3 terms, adj 1.0] ccs.ornl.gov date: 08-Apr-95 bytes: 3364 links: 2 title: VORTEX outline: MICROSCOPIC THEORY OF THE VORTEX STATE IN SUPERCONDUCTORS keys: superconductors superconductor excerpt: VORTEX MICROSCOPIC THEORY OF THE VORTEX STATE IN SUPERCONDUCTORS The objective of gaining a full understanding of the properties of superconductors has been a high priority in condensed matter physics in recent years, especially since the discovery in 1987 of high temperature superconductors. In particular, the nature of the vortex state for a regular periodic lattice is not well understood. The vortex state arises when a magnetic field, which is typically deleterious to superconductivity, can penetrate a superconductor by creating normal (non-superconducting) regions, the vortex centres. Although the existence of the vortex state was suggested from a phenomenological -------------------------------------------------------------------------------- ID187758: [score 0.9093, 3 of 3 terms, adj 0.9] iqe.ethz.ch date: 31-Mar-95 bytes: 4471 links: 2 title: INTERACTION OF LASER RADIATION WITH MATTER outline: interaction of laser radiation with matter keys: superconductor superconductors excerpt: INTERACTION OF LASER RADIATION WITH MATTER Infrared Physics Laboratory , ETH Zürich interaction of laser radiation with matter Contents Interaction of High Tc Superconductors with Ultrashort Infrared Pulses Characterization of Coating Adhesion by Laser-Induced Spallation Interaction of High Tc Superconductors with Ultrashort Infrared Pulses (D.B. Moix, D.P. Scherrer, F.K. Kneubühl) in cooperation with the University of Neuchâtel We have investigated the response of the high-Tc superconductor YBa2Cu3O7-d ( Tc = 90 K) to 10'000 nm 35 ps pulses generated by our OFID system [1]. The laboratory of Prof Dr Martinoli at the Universi... Different kinds of signals have been observed. For temperatures below the transition temperature, the signal full -------------------------------------------------------------------------------- ID424540: [score 0.8223, 3 of 3 terms, adj 1.0] ornl.gov date: 25-Mar-95 bytes: 4559 links: 6 title: High Temperature Superconductors outline: High Temperature Superconductors New Materials and Power Applications: Superconducting Devices: Working with ORNL in High Temperature Superconductivity: keys: superconductors temperature excerpt: High Temperature Superconductors High Temperature Superconductors High Temperature Superconductors The discovery of high-temperature superconducting materials in 1986 sparked a dream of an amazing new electrical world--a world of loss-free power transmission from coast to coast, of enormously powerful computers, and of levitated trains passing in a blur of speed. Oak Ridge National Laboratory is helping to make the dream of high-temperature (up to 135 K from 20 K) superconductivity a reality. Since 1988, our High Temperature Superconductivity Technology Center has blended materials research and wire development through Cooperative Research and Development Agreements with industry. CRADAs also offer opportunities for collaboration in development of power conductors -------------------------------------------------------------------------------- ID433592: [score 0.7463, 3 of 3 terms, adj 1.0] physics.utoronto.ca date: 10-Apr-95 bytes: 2238 links: 1 title: High Temperature Superconductivity outline: High Temperature Superconductivity keys: superconductors temperature excerpt: High Temperature Superconductivity Since the discovery of superconductors with transition temperatures well above the boiling point of liquid nitrogen, thousands of physicists, chemists, materials scientists and engineers have been at work studying their properties and searching for superconductors with yet higher transition temperatures. The superconductors already found have the potential to revolutionize technology as the transistor did over -------------------------------------------------------------------------------- ID395982: [score 0.7229, 3 of 3 terms, adj 1.0] llnl.gov date: 31-Mar-95 bytes: 7751 links: 12 title: Electro-Optic Sampling of HTSC Interconnects outline: Electro-Optic Sampling of HTSC Interconnects Nd:YAG laser used as the optical source Industrial partners sought Advantages keys: superconductor excerpt: Electro-Optic Sampling of HTSC Interconnects EO Sampling allows users to probe electrical transients "noninvasively" Advantages Electro-optic (EO) sampling capabilities are being developed to characterize the dispersion and loss properties of High Temperature Superconductor (HTSC) transmission lines and interconnects. The main advantage offered by EO sampling is the ability to noninvasively probe electrical transients which are propagating along a transmission line structure with sub-picosecond temporal resolution. Figure 1 illustrates the basic EO measurement system configuration. Figure 1. Schematic representation of electro-optic measurement system. Typically, an optical pulse is used as a "pump" which inserts a very fast electrical pulse or step onto a transmission descriptions: Electro-Optic Sampling of HTSC Interconnects -------------------------------------------------------------------------------- ID431869: [score 0.7176, 3 of 3 terms, adj 1.0] ph.ic.ac.uk date: 09-Apr-95 bytes: 13264 title: Experimental Solid State Physics outline: Experimental Solid State Physics Head of Group: Prof.R.A.Stradling keys: excerpt: Experimental Solid State Physics Head of Group: Prof.R.A.Stradling Much of the research within the Group involves samples prepared by the Interdisciplinary Research centre for Semiconductor Materials or in conjunction with the College Centre for High Temperature Super-conductivity. There is a strong emphasis on the optical, magnetic and electrical properties of solids. A new and unifying theme is emerging with the start of a project to fabricate and study hybrid superconductor - semiconductor proximity effect structures. Figure 1. Schematic representation of a quantum well showing allowed energy levels and wave functions of the confined electrons and holes. Quantum Transport in InAsSb-InSb Strained Layer Superlattices (R.A.Stradling) We have been studying the -------------------------------------------------------------------------------- ID157380: [score 0.7176, 3 of 3 terms, adj 1.0] euler.ph.ic.ac.uk date: 18-Mar-95 bytes: 13264 title: Experimental Solid State Physics outline: Experimental Solid State Physics Head of Group: Prof.R.A.Stradling keys: excerpt: Experimental Solid State Physics Head of Group: Prof.R.A.Stradling Much of the research within the Group involves samples prepared by the Interdisciplinary Research centre for Semiconductor Materials or in conjunction with the College Centre for High Temperature Super-conductivity. There is a strong emphasis on the optical, magnetic and electrical properties of solids. A new and unifying theme is emerging with the start of a project to fabricate and study hybrid superconductor - semiconductor proximity effect structures. Figure 1. Schematic representation of a quantum well showing allowed energy levels and wave functions of the confined electrons and holes. Quantum Transport in InAsSb-InSb Strained Layer Superlattices (R.A.Stradling) We have been studying the -------------------------------------------------------------------------------- ID212840: [score 0.7100, 3 of 3 terms, adj 1.0] oregon.uoregon.edu date: 02-Apr-95 bytes: 2114 links: 1 title: Research Topics outline: Active Research Topics in the Materials Science Institute keys: superconductors excerpt: Research Topics Active Research Topics in the Materials Science Institute the characterization of electronic materials and devices, solid state chemistry of reactions between thin elemental films, synthesis and characterization of high-technology ceramic oxides, including high-temperature superconductors, ultra-high vacuum surface science, laser-induced dynamics at interfaces, properties of amorphous semiconductors -------------------------------------------------------------------------------- To see more hits, use the Search form. back to the Lycos Home Page. -------------------------------------------------------------------------------- Chucka

To: Chuca Marsh who wrote (1240)	8/11/1999 10:42:00 AM
From: Chuca Marsh	Respond to of 1364

Another Hit note the WORD IMPURITIES is even stressed in these OLD FASHIONED CERAMIC TYPES that are now being displaced in NEW TeCH Applications: www2.csn.net THE MEISSNER EFFECT One of the properties of superconductors most easy to demonstrate, and also the most dazzling, is the Meissner Effect. Superconductors are strongly diamagnetic. That is to say that they will repel a magnet. Imagine a 'perfect' conductor of electricity that simply has no resistance to the flow of an electric current. If a conductor of electricity is moved into a magnetic field, Faraday's Law of Induction would lead us to expect an induced electrical current in the conductor and its associated magnetic field which would oppose the applied field. The induced electrical current would not dissipate in a 'perfect' conductor, and thus the associated magnetic field would also continue to oppose the applied field. Conversely, if the 'perfect' conductor was already in a magnetic field, and then that applied field was removed, the same physical law would indicate that an electrical current and its associated magnetic field would appear in the conductor which would attempt to oppose the removal of the applied field. If we were to do an experiment in which we placed a magnet on top of a material that by some process then became a 'perfect' conductor, we would see no physical effect on the magnet. However, were we to attempt to remove the magnet, only then would we feel an opposing force. A superconductor is fundamentally different from our imaginary 'perfect' conductor. Contrary to popular belief, Faraday's Law of induction alone does not explain magnetic repulsion by a superconductor. At a temperature below its Critical Temperature, Tc, a superconductor will not allow any magnetic field to freely enter it. This is because microscopic magnetic dipoles are induced in the superconductor that oppose the applied field. This induced field then repels the source of the applied field, and will consequently repel the magnet associated with that field. This implies that if a magnet was placed on top of the superconductor when the superconductor was above its Critical Temperature, and then it was cooled down to below Tc, the superconductor would then exclude the magnetic field of the magnet. This can be seen quite clearly since magnet itself is repelled, and thus is levitated above the superconductor. For this experiment to be successful, the force of repulsion must exceed the magnet's weight. This is indeed the case for the powerful rare earth magnets supplied with our kits. One must keep in mind that this phenomena will occur only if the strength of the applied magnetic field does not exceed the value of the Critical Magnetic Field, Hc for that superconductor material. This magnetic repulsion phenomena is called the Meissner Effect and is named after the person who first discovered it in 1933. It remains today as the most unique and dramatic demonstration of the phenomena of superconductivity. On account of the polycrystalline nature of a typical ceramic superconductor, the Meissner Effect appears to be a bulk phenomena. This can be demonstrated by stacking two or more superconductor disks. With the addition of each disk, the magnet will be levitated higher. This result is particularly advantageous if the Meissner Effect is being demonstrated to an audience with the help of an overhead projector. Another interesting observation is that the levitated magnet does not slide off the superconductor. This seemingly stable equilibrium is actually a manifestation of Flux Pinning, a phenomena uniquely associated with Type II superconductors, of which our high temperature ceramic superconductors are examples. Here lines of magnetic flux associated with a magnet can penetrate the bulk of the superconductor in the form of magnetic flux tubes. These flux tubes are then pinned to imperfections or impurities in the crystalline matrix of the superconductor thereby pinning the magnet. -------------------------------------------------------------------------------- Meissner Effect Demonstration The procedure below, will guide the experimenter through a demonstration of the Meissner Effect in a cookbook fashion, step by step. The shallow dish-like depression in the styrofoam container for the kit, or a third of an inch high portion of the bottom of a styrofoam coffee cup, can be used for holding liquid nitrogen for the experiment. To project a sharp image of the Meissner Effect with an overhead projector, use a very small dish so that the levitated magnet is less than an inch from its glass plate. Procedure ACTION: Carefully pour a small amount of liquid nitrogen into the dish or styrofoam cup until the liquid is about a quarter of an inch deep. RESULT: The liquid boils furiously for a short while. Wait until it stops boiling. ACTION: Using the provided tweezers, carefully place the black superconductor disk flat in the liquid until its top is just flush with the surface of the liquid nitrogen. RESULT: Again, the nitrogen boils around the disk. Wait until this boiling stops too. ACTION: Again using the tweezers, pick up the provided magnet, and attempt to balance it on top of the superconductor disk. RESULT: Instead of settling down onto the surface of the superconductor, the magnet will simply 'float' a few millimeters above the superconductor. This is a demonstration of the Meissner Effect. Precautions When pouring liquid nitrogen please be careful to prevent any splashing. Conduct the experiments in a well-ventilated room. Do not touch any items immersed in the liquid nitrogen with your hand until they have warmed to room temperature. Use the provided tweezers to add and remove items from the liquid nitrogen. -------------------------------------------------------------------------------- This experiment can also be conducted by placing the magnet on top of the superconductor before it is cooled in liquid nitrogen. As predicted by the Meissner Effect, the magnet will levitate when the temperature of the superconductor falls below its Critical Temperature. As explained earlier, there is no material other than a superconductor which could have shown this effect. If you carefully set the magnet rotating, you will observe that the magnet continues to rotate for a long time. This is a crude demonstration of a frictionless magnetic bearing using the Meissner Effect. The rotational speed of a cube-shaped magnet can be increased by using a plastic drinking straw to blow a stream of air at one of the edges or corners of the cube. Another way to increase the magnet's rotational speed is to cut out a small rectangular hole in a piece of paper. The hole is positioned over the levitated magnet such that half of the magnet projects above the plane of the paper. A stream of air directed along the upper surface of the paper will cause the magnet to rotate rapidly. The cubical magnet naturally is slowed by the resistance of air. Consequently, it can be expected to stop after a while. A cylindrical magnet will rotate for much longer since it is rotationally streamlined. However, the cubical magnet makes this demonstration much more graphic. A research group at Cornell University has demonstrated a frictionless superconducting bearing that can turn at a rate of one million rotations per minute. A bearing constructed in this manner, using the Meissner Effect is much more convenient and safe than a conventional magnet bearing because of the 'self-centering' nature of the Meissner Effect on account of flux pinning. All Kits from Colorado Superconductor Inc. are equipped to demonstrate the Meissner Effect. The Comparison Kits contain both a yttrium-based (YBa2Cu3O7) and a bismuth-based (BiSrCaCu2O9) superconductor. Both superconductors exhibit the Meissner Effect, however, if the disks are carefully removed from the liquid nitrogen bath, while magnet is still levitated, the bismuth-based material will continue levitating the magnet for a considerably longer time than the yttrium-based superconductor. This is because the bismuth-based superconductor has a significantly higher Critical Temperature than to the yttrium-based one. The Critical Temperature Kit and the Critical Temperature Comparison Kit both use the Meissner Effect to measure the Critical Temperature of superconductors. Chucka also: Meissner Effect Diagram explained:( not how diamonds are not in this FIRST generation S-C ity Demonstration, so purity our wafers, NUKE! RE: www2.csn.net 1)-Under some circumstances, the magnet will abruptly scoot to one side of the device as it warms. Can you think of an explanation for this? 2)-The device develops a layer of frost only after the liquid nitrogen has all boiled away. Why is this? 3)-Try the experiment by first placing the magnet on the superconducting device, and then cooling it down in liquid nitrogen. 4)-Do you observe any differences in the Critical Temperature? If so, why? The application of the Meissner Effect to measure the Critical Temperature was just one possible application of this effect. Can you think of other, elegant applications of this unique Effect? #3 pas.rochester.edu What's Important in This Lab As I said above, you should come away from this lab with an appreciation of the fact that superconductors can contain and pass electrical currents with absolutely no resistance, and that this fact leads to some interesting consequences (most notably, the Meissner effect: magnetic fields are not permitted to enter a superconductor, so all magnets are repelled by superconductors). Hints and Tips for making this lab a better experience Make sure to record the uncertainty associated with each type of measurement, along with some note about what gave rise to that uncertainty. You'll need it for doing the data analysis, and you need it to be complete... The lab manual available on the web has some slight typos, but they're just misspellings and won't affect the way you do the lab, so just be patient with Raf (one of the TAs for 114, who's had to update both the experiment and the manual during this semester, while teaching the other P114 labs and taking some actual classes himself). Part I (of the lab): Levitation No, we're not doing a David Copperfield show here; this is real levitation! The lab manual says to put the LN (short for Liquid Nitrogen) into the styrofoam tray (or, for the second part, the Petri dish) first, then put in the superconductor. {{ Ie - LN is the old cold way, we need no LN in our Aplication, that is very IMPORTANT with NUKE TECH in DIAMOND APPLICATIONS, 600 degrees F and it runs fine where old TECH at 150 -200+ and it breaks, think about that HOT FACT in that we still will work at 600 degrees-with Rhombic TECH!}} However, it then says to make sure that the liquid level should be right up to the top of the superconductor. Now, if you didn't put in enough LN then you can add some more, but if you put in too much then you'll just have to sit and wait. So, start with just a little bit, and add more if needed. Why is it important for the LN level to be even with the top of the superconductor? It's not critical, it's just that you'll get the best results that way. You see, if the level is too low then the top of the superconductor will tend to heat up and may cross its Tc and stop superconducting. On the other hand, if the level is too high, then the magnets that you'll be putting on top of the superconductors will sit in the liquid rather than being suspended in the air! This will give them much more resistance to moving than just air resistance, so they won't be able to spin for as long, and also for the second part it'll be hard to see how far above the superconductor the magnetic ring is... Part II: Critical Temperature If you read the old version of the manual ...