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Tuesday, June 21, 2022
06-21-2022-0813 - Sun Wrought Iron Rust Bluing Inhibitors Dessicant Nuclear Dessication Processes Coherency Magnet Magnetostatics Pressure Compression Condensed Coreular Unit Vaccume Filament Sheet Vortex Plane Fluid Thread Breakup dark matter energy CDM lambda observable universe microwave background radiation mag grav wave etc..
Rust is an iron oxide, a usually reddish-brown oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Rust consists of hydrous iron(III) oxides (Fe2O3·nH2O) and iron(III) oxide-hydroxide (FeO(OH), Fe(OH)3), and is typically associated with the corrosion of refined iron.
Associated reactions[edit]
The rusting of iron is an electrochemical process that begins with the transfer of electrons from iron to oxygen.[7] The iron is the reducing agent (gives up electrons) while the oxygen is the oxidizing agent (gains electrons). The rate of corrosion is affected by water and accelerated by electrolytes, as illustrated by the effects of road salt on the corrosion of automobiles. The key reaction is the reduction of oxygen:
Because it forms hydroxide ions, this process is strongly affected by the presence of acid. Likewise, the corrosion of most metals by oxygen is accelerated at low pH. Providing the electrons for the above reaction is the oxidation of iron that may be described as follows:
- Fe → Fe2+ + 2 e−
The following redox reaction also occurs in the presence of water and is crucial to the formation of rust:
- 4 Fe2+ + O2 → 4 Fe3+ + 2 O2−
In addition, the following multistep acid–base reactions affect the course of rust formation:
as do the following dehydration equilibria:
From the above equations, it is also seen that the corrosion products are dictated by the availability of water and oxygen. With limited dissolved oxygen, iron(II)-containing materials are favoured, including FeO and black lodestone or magnetite (Fe3O4). High oxygen concentrations favour ferric materials with the nominal formulae Fe(OH)3−xOx⁄2. The nature of rust changes with time, reflecting the slow rates of the reactions of solids.[5]
Furthermore, these complex processes are affected by the presence of other ions, such as Ca2+, which serve as electrolytes which accelerate rust formation, or combine with the hydroxides and oxides of iron to precipitate a variety of Ca, Fe, O, OH species.
The onset of rusting can also be detected in the laboratory with the use of ferroxyl indicator solution. The solution detects both Fe2+ ions and hydroxyl ions. Formation of Fe2+ ions and hydroxyl ions are indicated by blue and pink patches respectively.
Bluing[edit]
Bluing is a technique that can provide limited resistance to rusting for small steel items, such as firearms; for it to be successful, a water-displacing oil is rubbed onto the blued steel and other steel.
Inhibitors[edit]
Corrosion inhibitors, such as gas-phase or volatile inhibitors, can be used to prevent corrosion inside sealed systems. They are not effective when air circulation disperses them, and brings in fresh oxygen and moisture.
Humidity control[edit]
Rust can be avoided by controlling the moisture in the atmosphere.[17] An example of this is the use of silica gel packets to control humidity in equipment shipped by sea.
Rust may be treated with commercial products known as rust converter which contain tannic acid or phosphoric acid which combines with rust; removed with organic acids like citric acid and vinegar or the stronger hydrochloric acid; or removed with chelating agents as in some commercial formulations or even a solution of molasses.[19]
https://en.wikipedia.org/wiki/Rust
Wrought iron is an iron alloy with a very low carbon content (less than 0.08%) in contrast to that of cast iron (2.1% to 4%). It is a semi-fused mass of iron with fibrous slag inclusions (up to 2% by weight), which gives it a "grain" resembling wood that is visible when it is etched, rusted, or bent to the point of failure. Wrought iron is tough, malleable, ductile, corrosion resistant, and easily forge welded, but is more difficult to weld electrically.
Before the development of effective methods of steelmaking and the availability of large quantities of steel, wrought iron was the most common form of malleable iron. It was given the name wrought because it was hammered, rolled or otherwise worked while hot enough to expel molten slag. The modern functional equivalent of wrought iron is mild steel, also called low-carbon steel. Neither wrought iron nor mild steel contains enough carbon to be hardenable by heating and quenching.[1]: 145 [failed verification]
Wrought iron is highly refined, with a small amount of silicate slag forged out into fibres. It consists of around 99.4% iron by mass.[2] The presence of slag can be beneficial for blacksmithing operations, such as forge welding, due to the silicate inclusions being a flux, and gives the material its unique fibrous structure.[3] The silicate filaments of the slag also protect the iron from corrosion and diminish the effect of fatigue caused by shock and vibration.[4]
Historically, a modest amount of wrought iron was refined into steel, which was used mainly to produce swords, cutlery, chisels, axes and other edged tools as well as springs and files. The demand for wrought iron reached its peak in the 1860s, being in high demand for ironclad warships and railway use. However, as properties such as brittleness of mild steel improved with better ferrous metallurgy and as steel became less costly to make thanks to the Bessemer processand the Siemens-Martin process, the use of wrought iron declined.
Many items, before they came to be made of mild steel, were produced from wrought iron, including rivets, nails, wire, chains, rails, railway couplings, water and steam pipes, nuts, bolts, horseshoes, handrails, wagon tires, straps for timber roof trusses, and ornamental ironwork, among many other things.[5][note 1]
Wrought iron is no longer produced on a commercial scale. Many products described as wrought iron, such as guard rails, garden furniture[6] and gates, are actually made of mild steel.[7] They retain that description because they are made to resemble objects which in the past were wrought (worked) by hand by a blacksmith (although many decorative iron objects, including fences and gates, were often cast rather than wrought).[7]
https://en.wikipedia.org/wiki/Wrought_iron
Photospheric composition (by mass) | |
---|---|
Hydrogen | 73.46%[17] |
Helium | 24.85% |
Oxygen | 0.77% |
Carbon | 0.29% |
Iron | 0.16% |
Neon | 0.12% |
Nitrogen | 0.09% |
Silicon | 0.07% |
Magnesium | 0.05% |
Sulphur | 0.04% |
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06-21-2022-0503 - Per- and Polyfluoroalkyl Substances (PFAS) [FDA](Rf.CFR)[USA NAC DOM]
Per- and Polyfluoroalkyl Substances (PFAS)
State & Federal Collaboration
As the science on PFAS advances, the FDA works with states and other federal agencies to identify and assess the safety of locally grown and produced foods from areas with known PFAS contamination. With states, this support generally takes the form of assistance with analytical testing, method development, and safety assessment consultations, and occurs at the request of states. The FDA has provided on-going assistance to states in their assessment of several different kinds of foods including crops for human and animal food, and animal derived foods. As appropriate to the food type, this consultation may be provided in conjunction with other federal agencies.
In addition, the FDA has joined the government-wide approach led by The White House to further advance critical progress on securing clean air, safe food, and clean drinking water. Through this collaboration with other federal agencies, we will work to identify routes of PFAS exposure, understand associated health risks, and reduce the public’s dietary exposure to PFAS that may pose a health risk.
For more information on the federal government’s approach for reducing exposure to PFAS, please see: FACT SHEET: Biden-Harris Administration Launches Plan to Combat PFAS Pollution
https://www.fda.gov/food/chemical-contaminants-food/and-polyfluoroalkyl-substances-pfas
https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/cfrsearch.cfm
https://www.fda.gov/Drugs
https://www.whitehouse.gov
06-21-2022-0425 - Scientists Spot First 'Sunquake' of the Current Solar Cycle
Scientists Spot First 'Sunquake' of the Current Solar Cycle
Sunspot activity is intensifying on our neighborhood star, increasing the likelihood of some of the most powerful tremors known.
https://www.cnet.com/science/space/scientists-spot-first-sunquake-of-the-current-solar-cycle/
06-21-2022-0237 - Why Did Sunspots Disappear for 70 Years? Nearby Star Holds Clues
Why Did Sunspots Disappear for 70 Years? Nearby Star Holds Clues
Five decades of data revealed a star undergoing a pause in magnetic activity similar to what the Sun experienced almost 400 years ago.
Every 11 years, the number of spots dotting the surface of the Sun increases and decreases like clockwork. Astronomers have been tracking the 11-year sunspot cycle for more than 400 years, using it to better understand the chaotic magnetic field the Sun puts out. (The current solar cycle, number 25, started in 2019.) The timing of the solar cycle is remarkably consistent: Sunspot numbers rise and fall, rise and fall…except for that time that they disappeared and weren’t seen again for 70 years.
That period of time, from 1645 to 1715, is known as the Maunder Minimum, named after 19th century British astronomers Edward and Annie Maunder. Astronomers still don’t understand why the Sun ceased making sunspots for 70 years, but a new analysis of more than 5 decades of measurements of nearby stars has identified one that might be undergoing its own Maunder-like minimum. The star, HD 166620, could help scientists understand this mysteriously quiescent period of the Sun’s history and unlock clues about how the solar dynamo functions.
“We can’t build a time machine and go back to the Maunder Minimum and study the Sun as it was,” said Jason Wright, an astronomer at Pennsylvania State University in University Park and a coauthor on the new analysis. “But we can find an analog and study its Maunder minimum.”
https://eos.org/articles/why-did-sunspots-disappear-for-70-years-nearby-star-holds-clues
A pulsar wind nebula is created when the powerful magnetic field of a rapidly spinning neutron star accelerates surrounding charged particles to nearly the speed of light. Probably the most famous example of this type of nebula is the Crab Nebula in the constellation of Taurus — the result of a supernova that shone brightly in 1054 CE.
http://www.sci-news.com/astronomy/pulsar-wind-nebula-distant-dwarf-galaxy-10907.html
However, only about two dozen have been definitively detected, all in binary systems. Beyond the Milky Way, over 80 binary black hole mergers have been detected via gravitational waves.
http://www.sci-news.com/astronomy/microlensing-black-hole-10896.html
Time Time
Watch 'Dead' Sunspot Explode, Launch Solar Material Towards Earth
GALILEO SPOTTED STARSPOTS
Starspots appear as a dark spot on a star’s surface due to temporary lower temperatures in the area resulting from the star’s dynamo—the process that creates its magnetic field.
Astronomers have been documenting changes in starspot frequency on our sun since they were first observed by Galileo and other astronomers in the 1600s, so there is a good record of its 11-year cycle. The exception is the Maunder Minimum, which lasted from the mid-1600s to the early 1700s and has perplexed astronomers ever since.
“We don’t really know what caused the Maunder Minimum, and we have been looking to other sun-like stars to see if they can offer some insight,” says first author Anna Baum, an undergraduate at Penn State at the time of the research.
“We have identified a star that we believe has entered a state similar to the Maunder Minimum. It will be really exciting to continue to observe this star during, and hopefully as it comes out of, this minimum, which could be extremely informative about the sun’s activity 300 years ago.”
MAGNETICALLY ‘DEAD’ STARS
The research team pulled data from multiple sources to stitch together 50 to 60 years of starspot data for 59 stars. This included data from the Mount Wilson Observatory HK Project—designed to study stellar surface activity and ran from 1966 to 1996—and from planet searches at Keck Observatory which include this kind of data as part of their ongoing search for exoplanets from 1996 to 2020.
The researchers compiled a database of stars that appeared in both sources and that had other readily available information that might help explain starspot activity. The team also made considerable efforts to standardize measurements from the different telescopes to be able to compare them directly and otherwise clean up the data.
The team identified or confirmed that 29 of these stars have starspot cycles by observing at least two full periods of cycles, which often last more than a decade. Some stars did not appear to have cycles at all, which could be because they are rotating too slowly to have a dynamo and are magnetically “dead” or because they are near the end of their lives. Several of the stars require further study to confirm whether they have a cycle.
“This continuous, more than 50-year time series allows us to see things that we never would have noticed from the 10-year snapshots that we were doing before,” says Jason Wright, professor of astronomy and astrophysics and an author of the paper. “Excitingly, Anna has found a promising star that was cycling for decades but appears to have stopped.”
According to the researchers, the star—called HD 166620—was estimated to have a cycle of about 17 years but has now entered a period of low activity and has shown no signs of starspots since 2003.
“When we first saw this data, we thought it must have been a mistake, that we pulled together data from two different stars or there was a typo in the catalog or the star was misidentified,” says Jacob Luhn, a graduate student at Penn State when the project began who is now at the University of California, Irvine.
https://www.futurity.org/maunder-minimum-sunspots-sun-space-2715932/
DR. SKY BLOG
Massive sunspot group producing X-level flares and CME events in cycle 25
For a week or so, something has been brewing on the far side of the sun.
With sunspot cycle 25 now underway, the activity on the far side has been producing X-level solar flares and powerful coronal mass ejections.
As the new sunspot group moves into view, expect more in the way of above normal flare and related radiation storms from the sun.
Here is a view of the massive sunspot chain known as AR 2993-2994, as they are seething with magnetic fields.