Finnish Specialglass Oy
http://www.finnishspecialglass…ecialglass-in-a-nutshell/
They make all kinds of quartz products based on customer's drawings and specifications.
pjs
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Cherenkov radiation
Charged particles passing through a dielectric medium at very high speed -
Fusionist's original post about the RAGOEL reactor material
MFMP: New Dog-Bone run tomorrow!A couple of comments
Several different grades of Fiberfrax fibers exist.
www.unifrax.eu.com
Product lines / Fiberfrax
http://www.unifrax.eu.com/web/Audit.nsf/ByUNID/2F0E7708C6339BF185257EFA002085FA/$File/Fiberfrax Bulk & Chopped Fibres EN.pdfSome of the grades have fibers coated with an organic lubricant.
Other grades are without the organic lubricant.
The surface of fibers may have different kind of composition depending on the grade after heating the fibers at high temperature.
Heating fibers coated with an organic lubricant in reducing atmosphere (hydrogen) may leave some carbon (in the form of elemental carbon, graphite?) on the surface of fibers.
Grade temperature 1250 °C and 1350 °C fibers contain aluminum oxide and silicon dioxide in the form of aluminum silicate.
Grade temperature 1400 °C fibers contain aluminum oxide, silicon dioxide and zirconium dioxide in the form of aluminum silicate and possibly zirconium silicate. -
Interesting things can be done with laser pulses that generate MeV electrons.
http://arxiv.org/abs/1506.02912v1
We demonstrate laser-plasma acceleration of high charge electron beams to the ~10 MeV scale using ultrashort laser pulses with as little energy as 10 mJ.
In summary, we have demonstrated electron acceleration to the 10 MeV scale with laser pulses well below 1 terawatt,
using a thin, high density hydrogen gas jet, with efficiency of laser energy to MeV electrons of a few percent.Physical Review Letters
http://journals.aps.org/prl/ab…03/PhysRevLett.115.194802
Our results enable truly portable applications of laser-driven acceleration, such as low dose radiography, ultrafast probing of matter, and isotope production.The secondary effect of bright, extremely brief flashes of light is the result of the initial accelerations of electrons within the plasma wake,
as they are accelerated from rest to almost the speed of light in less than 1 millionth of a meter.
http://www.ece.umd.edu/news/news_story.php?id=9346 -
Thank you Ecco for the good reference.
In Bob Higgins' paper it is said that nickel powder was mixed with Fe2O3 nanopowder.
After reducing the material at high temperature with hydrogen the composition of the material
is probably nickel with iron on surface if water vapor (reaction by-product) has been removed from the reduction space,
because nickel oxides and iron oxides are not stable in the presense of hot hydrogen gas.On the other hand, after reducing a styrene catalyst the composition of the catalyst is iron(Fe), potassium oxide
(in the form of K2O and possibly some potassium ferrite K2Fe22O34),
and structural promoters stable in hydrogen atmosphere such as aluminum oxide (Al2O3) and chromium oxide (Cr2O3).The difference in catalytic activity between pure iron and iron with structural promoters would be interesting.
That raises some thoughts about
local broken structural symmetry and high catalytic activity.Crystal classes and mineralogy
http://www.tulane.edu/~sanelson/eens211/32crystalclass.htmIron has cubic crystal structure.
https://en.wikipedia.org/wiki/Allotropes_of_ironNickel has cubic crystal structure.
https://en.wikipedia.org/wiki/NickelAl2O3 and Cr2O3 have hexagonal crystal stucture which is their thermodynamically stable form.
https://en.wikipedia.org/wiki/Aluminium_oxide
https://en.wikipedia.org/wiki/Chromium(III)_oxideThere is a structural discontinuity between iron and Al2O3, Cr2O3 crystallites because they have different crystal structures.
These grain boundaries (crystallite boundaries) have lost
structural symmetry and they are more or less amorphous without any specific crystal structure.Atoms at grain boundaries tend to be loosely bound and are more reactive.
Atoms at grain boundaries have increased diffusion along grain boundaries.Because of similar crystal structure and absence of structural promoters,
having pure iron on pure nickel may during heating lead to the formation of iron-nickel alloys
that have large crystallites with relatively small amount of grain boundaries.If pure Fe2O3 powder is reduced with hydrogen gas, any stabilizing second phase particles
will probably not be present in the resulting pure iron metal powder and grain growth
will not be inhibited at high temperatures.
Surface area of iron powder will decrease because of increasing grain (crystallite) size.
Interfaces with defects will be lost because the number of separate crystallites will decrease during heating.
Larger crystallites consume smaller crystallites.
Pure iron particles easily sinter together at high temperatures and surface area decreases.Grain growth can be inhibited by certain second phase particles.
https://en.wikipedia.org/wiki/Grain_boundaryAfter reducing ammonia or styrene catalyst so that iron oxides have been converted into iron metal,
we have the first phase (iron) and the second phase (such as Al2O3, Cr2O3) which prevents the growth of large iron crystals.
Small iron crystallites survive in this stabilized material and the catalyst stays active at high temperatures for a long time.
All these materials have high melting points.
Iron melts at about 1538 degrees C.
Al2O3 melts at about 2072 degrees C.
Cr2O3 melts at about 2435 degrees C.In literature, dealing with another hydrogenation catalyst Ni/Al2O3, it is said that
"the more difficult the reduction of nickel oxide to metallic nickel, the lower the catalytic activity"
Reference
Effect of Alumina Particle Size on Ni/Al2O3 Catalysts for p-Nitrophenol Hydrogenation
http://www.sciencedirect.com/s…cle/pii/S1004954108600191Catalysts have a lot of structure defects (grain boundaries).
On the other hand, in metallurgy it is known that structure defects may collect hydrogen.
Reference
https://hal.archives-ouvertes.fr/jpa-00222298/document
"Hydrogen has a strong tendency to segregate in structure defects, among them, in grain boundaries."An efficient hydrogen catalyst seems to benefit from
- high surface area between a solid catalyst material and hydrogen gas (catalyst consisting of small metal crystallites in the form of nanoparticles or very rough surfaces)
- large number of grain boundaries that have been stabilized with structural promoters
- removal of surface oxides of metals by reductionThe role of alkali metals in catalysts and means of agitating catalysts with forms of energy are interesting subjects.
Perhaps another post later dealing with those topics. -
Talking about industrial hydrogen catalysts, here are a couple of examples.
In this case the goal for using a hydrogen catalyst is to dissociate molecular hydrogen (H2) to atomic hydrogen (H) that adsorbs on surface and is available for further reactions. In other words, here dissociation means breaking of the hydrogen – hydrogen chemical bond of molecular hydrogen H2.
Spicing up the nickel – lithium – hydrogen system with additional hydrogen catalysts creates some process challenges.A typical styrene catalyst contains iron oxide (hematite, Fe2O3), potassium oxide (K2O) and structural promoters such as aluminum oxide (Al2O3) and chromium oxide (Cr2O3).
Heating styrene catalyst in hydrogen gas generates water vapor. Fe2O3 is reduced with hydrogen into Fe3O4, FeO and at least partially into metallic iron, but increasing water vapor concentration in a closed reaction space disturbs the reduction process and especially the formation of metallic iron is difficult. Potassium oxide, aluminum oxide and chromium oxide have very strong metal – oxygen bonds and they are not reduced with hydrogen gas. Metallic lithium does not survive in contact with water vapor. Lithium is converted into lithium oxide or lithium hydroxide. Water vapor and sources of water vapor are preferably eliminated before introducing metallic alkali metals to the reaction space.Reduction behavior of iron oxides in hydrogen and carbon monoxide atmospheres
http://dx.doi.org/10.1016/j.apcata.2007.03.021
Having hot metallic alkali metal, e.g. lithium, in contact with iron oxide also causes a chemical reaction that consumes metallic alkali metal. Alkali metal forms strong chemical bond with oxygen. Alkali metal removes oxygen from iron oxide and alkali metal is oxidized into alkali metal oxide. As a consequence, free metallic alkali metal is lost permanently.
Metallic alkali metals such as lithium metal are thus lost in the presence of water vapor and metal oxides that have weak metal-oxygen bonds. In the presence of free oxygen or loosely bound oxygen, alkali metals are permanently oxidized into alkali metal oxides. Hydrogen cannot reduce alkali metal oxides or hydroxides back into elemental alkali metals. Metal oxides with weak metal-oxygen chemicals bonds should preferably be reduced before introducing metallic alkali metals to the reaction space.Industrial ammonia catalyst serves as an example of an alternative hydrogen catalyst.
A typical ammonia catalyst for the Haber-Bosch process contains several phases after reduction: the core of the catalyst particles may have magnetite (Fe3O4) covered with a layer of wüstite (FeO) and finally elemental iron (Fe) on the surface of the particle. This catalyst is usually promoted with potassium oxide (K2O), calcium oxide (CaO), silicon dioxide (SiO2) and aluminum oxide (Al2O3). There is iron in the form of about 10-30 nm iron crystallites on the surface. The catalyst is paracrystalline with a lot of lattice defects and it has high surface area because of a porous structure.
The ammonia catalyst in reduced form with iron crystallites on surfaces is pyrophoric and it may ignite spontaneously in air, and iron burns into iron oxide. Pre-reduced catalyst is typically partially passivated by forming a thin layer of iron oxide on iron surface and that eliminates pyrophoric properties of the catalyst. That iron oxide surface must be reduced e.g. with flowing hydrogen gas into elemental iron before the catalyst can be used.
Thus in case of using both metallic lithium and iron-based catalyst in a test system, it is very useful to pretreat the iron-based catalyst to reduce any surface iron oxides into metallic iron before loading the iron-based catalyst into the test system. Although actual LENR tests are typically done in high purity hydrogen atmosphere, reduction preceding the tests can be done at elevated temperature for example with flowing 5% hydrogen 95% argon mixture to remove from the heated reduction space any water vapor that has been generated in the reduction process. Reduced iron-based catalyst is very sensitive to air and water vapor, so the pretreated (reduced) catalyst must be handled and loaded to the test system in inert or reducing gas atmosphere.As a summary, oxygen (air) and water vapor are harmful for metallic alkali metals and for these hydrogen catalysts.
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Here are some thoughts about light and SERS-active materials for LENR experiments.
First a selection of excerpt from published papers.
SERS Surface enhanced Raman spectroscopy
http://www.cem.msu.edu/~cem924sg/ChristineHicks.pdf
SERS: Materials, applications, and the future
http://sites.northwestern.edu/…ations-and-the-future.pdf
Surface-Enhanced Raman Spectroscopy
http://pubs.acs.org/doi/abs/10.1021/ac00181a001The most effective substrates for SERS consist of small metal particles or rough surfaces of conductive materials.
Particle sizes or roughness features are on the order of tens of nanometers.
Classic SERS-active substrates having plasmonic nanostructures are made of gold, silver or copper.
Alkali metals (lithium, sodium, potassium, rubidium and cesium) form good SERS-active substrates,
but alkali metals must be handled and kept in inert or reducing atmosphere.
Alkali metals react very quickly with moisture and air and the desired properties of alkali metal surfaces are lost.
The excitation wavelength of the electromagnetic radiation is near the visible region or in the visible region.Palladium and platinum exhibit some enhancements for excitation in the near ultraviolet.
Metallic aluminum has main plasmon band in the UV region.Light incident on metal nanoparticles or metal surface roughness features, such as nanovoids or nanoprotrusions,
can excite conduction electrons, generating a localized surface plasmon or plasmon resonance.
Since the surface electrons of the metal are here confined to a small space,
the plasmon’s excitation is also confined to the metal nanoparticle or roughness feature of the metal.
The resulting electromagnetic field of the plasmon is very intense.
The field enhancement is greatest when the plasmon frequency is in resonance with the electromagnetic radiation.
The metal nanoparticle or roughness feature of the metal becomes polarized,
and the electromagnetic field in the interior of the metal becomes significantly larger than the applied field.Here are some thoughts about making LENR experiments with light and SERS-active materials.
Arranging a light source inside the LENR test system has been rather demanding because of the high operating temperature of the LENR test system.
Conveying light with an optical fiber from an external light source to the LENR test system or through a transparent window to the LENR test system will be challenging in case of high hydrogen gas pressure in the test system.Flashtubes provide tremendous peak power light pulses.
Release of light energy is squeezed to a very short period of time.
However, the time averaged power consumption of electricity is very reasonable and easily arranged.
For example, if a 330 microfarad capacitor is charged to 300 V, about 15 J (15 Ws) of energy is stored to the capacitor.
It is said that a good flashtube converts up to almost 50% of electrical energy into light.
If the duration of the flash is 0,001 s (1 ms), the momentary light power will be 0,5 * 15 Ws / 0,001 s = 7,5 kW.
Time averaged light power is just 0,5 * 15 Ws / 10 s = 0,75 W, so in this case there is nothing extraordinary in the test system
containing nickel, hydrogen and a SERS-active material if thermal power obtained from the heated test system
increases no more than 0,75 W compared to a test system that is only heated without adding light energy to the test system.If recharging the capacitor takes 10 s, average electrical charging power is only 15 Ws / 10 s = 1,5 W.
Especially if a flashtube is driven below the rated power, the lifetime of the flashtube can be in the order 1 – 10 million flashes.
Getting e.g. one flash / 10 s from the flashtube means 115 – 1150 days lifetime.
Even if the ceramic tube of the LENR test system is only translucent, some part of the light pulse from the flashtube
will be transmitted through the ceramic wall and received by the SERS-active surface.
In case of a reaction chamber made of metal or other opaque material, a transparent window (e.g. sapphire window)
or a quartz optical fiber will help to introduce light or pulses of light into the reaction chamber. -
Potassium and sodium oxides and also other alkali metal oxides have significant vapor pressure already below 1000 °C.
They would have vaporized from hot areas of the reaction chamber and condensed in cooler areas of the reaction chamber.High temperature vaporization behavior of oxides. I. Alkali metal binary oxides
http://www.nist.gov/data/PDFfiles/jpcrd241.pdfThe powder would have lost alkali metal oxides during long heating time.
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Interesting ... the patent application had been kept undercover with the nonpublication request document until granting.
http://portal.uspto.gov/pair/PublicPair -
Regarding the temperature in experiments, please take into consideration the energy levels of the valence electron in atoms.
Keywords: Hydrogen spectral series
n = ∞ (ionization) 0,0 eV
n = 2 (the first excited state, Lyman series) -3,4 eV
n = 1 (ground state) -13,6 eVWhen the electron of the neutral hydrogen atom is excited from n = 1 to n = 2, the excited electron of this Rydberg hydrogen atom is only 3,4 eV away from the ionization level.
Higher excitation levels of the electron would be even more sensitive to ionization.
According to the conversion formula hc = 1240 eV/nm, the 3,4 eV energy corresponds to 365 nm wavelength.
Thermal radiation extends to a very wide wavelength range.Keywords: thermal blackbody radiation
For example at 1000 °C a tiny part of thermal radiation photons already is at 3,4 eV energy level.Keywords: Rydberg formula for any hydrogen-like element
It is easier to excite the valence electron of alkali atoms, e.g. lithium atom, that the electron of hydrogen.
Only 5,39 eV is needed for lifting the valence electron of lithium from the ground state to the ionization level.Keywords: lithium energy levels
The difference between the 2s, 2p and 3s energy levels in the valence electron of lithium is relatively small.
That indicates that the formation of Rydberg lithium atoms by thermal energy is easier that the formation of hydrogen Rydberg atoms where the first step requires 10,2 eV.
On the other hand, Rydberg lithium atoms may be vulnerable to ionization because the energy levels are closer to each other than in hydrogen atom.
Nickel also has Rydberg levels.Some subjects that strain brains …
Energy transfer from Rydberg alkali metal atoms to hydrogen atoms in hydrogen catalysts?
Formation of Rydberg alkali atom – Rydberg hydrogen atom combinations?
Excitation levels of valence electrons of neutral atoms on surfaces?
Enthalpy of formation of Rydberg atom clusters -> deepness of the potential energy well -> sensitivity to ionization (decomposition) by thermal energy?