Below nano gets more interesting

Last blog mentioned metallic hydrogen at a very small level.  As the computational power increases, we are able to examine (theoretically at least) the behavior of various materials.  There is a significant amount of effort being directed at the investigation of a new state of matter of metals, defined as “strange metals”, which actually involves understanding the behavior of the electrons.

The difference from traditional understanding of metals, is that “strange” metals have electrical resistance directly linked to its temperature.  The conductivity is linked to both Planck’s constant and Boltzmann’s constant.  [Ref. 1]  Planck’s constant establishes the energy a photon can have, while the Boltzmann constant is the relationship of the kinetic energy of particles in a gas with temperature of the gas. 

According to Reference 2, a robust computational model of “strange’ metals provided sufficient details to classify these “strange” metals existing in a new state of matter.  Their explanation of “strange” metals is that the name is generated base on the behavior of electrons in the metal.  In metals, electrons travel freely in the material with little resistance and few interactions.  “Strange” metal electrons are more restricted and slower moving that would be anticipated.  In effect, “strange” metals are not metal nor insulator.  The referenced article also employs the term “reluctant” metals.

This discovery is a result of research on high-temperature super-conductivity [Ref. 3]  In 1990, researchers discovered that cuprates have a strange behavior that does not vary with temperature as anticipated or as other high temperature super-conductors.  Current theory can explain superconducting  properties below 30 K, but that property up to temperatures of 130 K  was puzzling.  Fermi liquid theory predicts that at low temperatures, the metal resistance should depend on the square of the temperature.  Cuprates resistance varies linearly down to when they become superconducting.  This testing has been performed at a wide range of temperatures and with field strengths of up to 80 T (tesla).

Some research at TU Wien (Vienna University of Technology) is focused on developing higher temperature super conducting materials [Ref. 4].  They have been using ytterbium, rhodium, and silicon (YbRn2Si2), which is know for its “strange” properties.  They are using a new molecular beam epitaxy (MBE) process.  They build the layers of the material atomic layer by atomic layer.  (A side issue was to create the substrate for building the material.  Germanium turns out to be a geometrical match for the structure of the new material.  They have found that a sudden change in the carrier concentration induces the “strange” metal state.  Significant additional work needs to be done to understand the state of the materials before any development can proceed.

The implications of this work are many.  While the mention of super conductivity has been basis for projections of high speed transport via magnetic levitation, the increase in conductivity could increase the effective amount of electrical power for everyone.  Currently, the transmissions losses are significant and being able to almost eliminate the losses would effectively increase the electrical power available.  This type of application becoming mainstream is based on atomic level precision and methods of building materials layer by atomic layer.   That ability to create very large amounts of the material is still a few years in the future.  Tools need to be developed and techniques for measuring and evaluating the resultant materials need to be developed.  This is part of the continual search for new material properties starting at the atomic and nanometer sizes.   

References:

  1. https://newatlas.com/physics/strange-metals-new-state-of-matter/
  2. https://physicsworld.com/a/reluctant-metals-make-a-new-state-of-matter/
  3. https://physicsworld.com/a/strange-metals-become-even-stranger/
  4. https://www.eurekalert.org/pub_releases/2020-01/vuot-anl011620.php

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Interesting things

A couple thoughts on Hydrogen.  This might be old news to some, but two Harvard scientists have created metallic hydrogen [Ref. 1] by employing extreme pressures. This material is predicted to be metastable.  This implies that when the pressure is removed, the hydrogen will remain as a metal.  The example employed indicates that diamond, a metastable form of graphite, remains as a solid unless it is heated to a very  high temperature when I will revert to graphite.

This achievement has been pursued over the last century.  The possibility exists that the metallic hydrogen might possibly be a room temperature superconductor.   One advantage for propulsion systems is that metallic hydrogen should have more than three times the energy release than liquid hydrogen.   The work will continue without any short term promises of quantities of the material being available.

 An Indiana firm has a process for operating vehicles using hydrogen for fuel [Ref. 2].  It is currently retrofitting a truck for the city of Carmel, Indiana.  The process employed requires a less than one-hundred-pound metal box with a device that manufactures hydrogen, which is fed into the modified engine.  The critical component of this device contains six stainless steel canisters with a 113 gram “button” of aluminum and a gallium alloy.  A small amount of water drips onto the buttons creating a chemical reaction that separates the hydrogen and oxygen in the water.  The hydrogen is released and the oxygen forms aluminum oxide.  If the buttons are depleted, the truck will resort to traditional fuel. 

Many companies are experimenting with hydrogen powered vehicles.  The major issue is the availability of the hydrogen.  Plus, the majority of the hydrogen powered vehicles require a refueling that involves some form of liquid.  This limits the usability of hydrogen powered vehicles.  This “pellet” approach might provide a means of accelerating the application of hydrogen for a fuel.  The Residue of the product is water, which is not a pollutant. 

Back to ethics and integrity.  It seems that the news is full of contradicting information regarding the current COVID-19 pandemic.  There are medical reports that have been recalled due to questionable results and the researchers’ refusal to provide information about their experiments.  Politics has jumped into the fray with all sorts of blame for someone else.  The issue also consists of the fact that people listening to the statements either do not understand or do not actually read what is being presented.

 The Kansas state’s health secretary created a chart that demonstrated the State’s mask mandate appeared successful.  The figure below is the original presentation to the general public.  It compares the rolling average of daily cases per 100K population for mask usage and non-mask usage.  The gold line is the mask usage and the blue line is non-mask usage.  The blue line is relatively consistent while the gold line shows a very significant reduction.  The media publicized this information as proving the validity of requiring masks [Ref. 3]. 

There is only one problem.  The “y” axes are different for each of the variables.  The data for the “official” chart from the State was taken from the chart below.  The impression provided by the state official was erroneous in order to get people to fall for it.  It was uncovered and published by Wall Street Journal. 

The issue with creating false information is that the public starts to not believe anything that officials state as needed.  The medical profession has firmly stated that masks are not required and then decided they are required.  Certain medications are helpful and no they are not.  A vaccine will be developed, and everyone should have one even though long-term effects are unknown.  Herd immunity might only take 60% immunization to be effective, but all other types of immunizations required over 90%.  Researchers produce reports that are then retracted or not able to be verified.  Can anyone be believed? 

Without the ability to trust anyone, how does a society operate?  We must get back to ethics and integrity in all phase of civilized life.

References:

  1. https://getpocket.com/explore/item/holy-grail-metallic-hydrogen-is-going-to-change-everything
  2. https://spectrum.ieee.org/energywise/transportation/alternative-transportation/hydrogen-on-tapdevice-trucks-fuel-efficient-vehicles?utm_source=energywise&utm_medium=email&utm_campaign=energywise-05-06-20&mkt_tok=eyJpIjoiT0Rjd09UWTJaakJtTVRGbCIsInQiOiJ0MWNlVVdVVWdTWFNqRHJ0ZXkyRHFMb25NY2NMeXdqQkVKb2dRR1JzbXpjUFwvaHVISlZIWWlDck9KU0Q0dkRmZmFXeldwa2JKQ2FvS045R1FuWFowV05TZUwwZmZSZ3hTalJEVUN2dUJMbGNlMjJia244VGdOdEtUNWlGUXdyZ3AifQ%3D%3D
  3. https://www.wsj.com/articles/kansas-democrats-covid-chart-masks-the-truth-11598483406?mod=opinion_lead_pos10

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New Developments in the World of Nano

Tools: In previous blogs I have mentioned that to truly work at a small scale, one needs to be able to measure to at least a dimension that is one-tenth the size of what you are measuring.  Ideally, the capabilities should be two orders of magnitude smaller.  This has been a real problem with material in the low double digit and single digit nanometer scale.  There is a report [Ref. 1] from two researchers at UC Irvine have developed a methodology using a scanning transmission electron microscope to image charge density at sub-angstrom scales.  This is in the early stages of development and there are limitations on sample sizes and spatial resolution in their current equipment.  They project that learning from this initial effort will provide the direction for novel measurement capabilities.

So, what is the principle on how this development works? “Nearly all the physical properties of materials are determined by how electron charge is rearranged between nuclei when atoms aggregate together. Being able to directly visualize how electrons are distributed is therefore important. Compared to other diffraction methods, aberration-corrected STEM (AC-STEM) allows for atomic-scale imaging of a sample using an electron beam, or probe, focused to about half an angstrom in size. When electrons pass through the sample, they interact with the internal electric field in their path through the Lorentz force. This changes the beam’s momentum, which can then be measured by diffraction.” [Ref. 1]

 The researchers work with a composite material employing ferroelectric oxide bismuth ferrite and oxide strontium titanite as the insulator.  They did a raster scan of a surface area and acquired a diffraction pattern at each point on the sample.  They then employed this technique to visualize the charge transfer between the two materials.  With high resolution there were able to determine the local charge distribution, which provides information on the distribution of the positive ionic cores and the separation of the electrons.  [Full paper available in Ref. 2]

Materials: A concern with materials in applications that are subjected to very low temperatures is that metals shrink.  (This is the opposite effect that water has as it turns into ice.)  This is true for planes and requires using composites and/or alloys with opposing expansion properties to balance the shrinkage out.  Research being conducted at the U.S. DoE Brookhaven National Laboratories is exploring a metal that dramatically expands at low temperatures. [Ref. 3] Using samarium sulfide doped with impurities, they are delving into details of the material’s atomic structure and the electron-based origins of the materials negative thermal expansion. 

Unlike water, with a good explanation of the expansion properties, the cause of the expansion of samarium sulfide was unknown.  This particular compound can be formed into two different types depending on the external condition in developing the material.  The gold-colored variety of the compound is a conductor with electrons moving freely, while the black -colored one is a semiconductor.  The resultant investigations and theoretical calculations pointed to a Kondo effect.  This effect is that electrons will interact with magnetic impurities and in a material and align spin in the opposite direction of the larger magnetic particles to cancel their effect.  It appears that the completeness of the outer electron shell is critical.  It appears that the negative thermal expansion of samarium sulfide can be tuned by varying the amount of impurities.  The researchers indicated that samarium, thulium, and ytterbium should all have properties that can be useful.

References:

  1. https://physicsworld.com/a/4d-electron-microscopy-images-charge-density-at-sub-angstrom-scales/?
  2. https://www.nature.com/articles/s41586-019-1649-6
  3. https://www.aerodefensetech.com/component/content/article/adt/supplements/amm/insider/36779?utm_source=TB_Aero_News&utm_medium=email&utm_campaign=20200430&oly_enc_id=2682C9224356G9L

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Updates and Some Nanotechnology Developments

In doing research for an upcoming published paper, I ran across an interesting article.  In September 2019, a research article was published that postulated the worst case situation for a worldwide pandemic, of unknown origins, might have a devastating impact on the world.  This was the first annual report by the Global Preparedness Monitoring Board [Ref. 1].  This paper was published before the evidence of the coronavirus (COVID-19) was detected.  Consequently, these hypothetical findings were transferred to the projections of coronavirus impact.

In a related area, it appears that there are more instances of publications of faulty or purposely misleading scientific and medical research, even by prestigious researchers [Ref. 2, 3].  Whether it is researchers who refuse to provide details on their models or experts that have a segment of researchers in their field insisting on retracting papers, the overall effect is to build a distrust in any research that is published.  This will have serious consequences when the general public develops an attitude that all scientific pronouncements are not to be believed.

Back to nanotechnology.  A team from Binghamton University lead by Pu Zhang developed a liquid metal lattice material [Ref. 4].  The basic concept of the material is that a silicone shell holds the metal composite together, so the material can be crushed but is able to return to its original form.  The metal composite has a melting point of 62C, which enables a restructuring possible using heated water.  The concept relies on the shell to return to its original form.  Without that shell, the liquid metal would become a blob of metal.  In its solid form, the material is very strong and stable.  If is much more resistant to deformation than similar property-type polymers that are able to be reshaped.    

From Queensland University of Technology comes some computational studies that diamond-like carbon nanothreads could be employed in a strained mechanical battery system [Ref. 5].  As described in the referenced article: First described in 2015,  nanothreads joined a catalogue of carbon nanomaterials that have emerged over the past four decades. Nanothreads are 1D structures with carbon atoms linked by single bonds (like those in diamond) to three other carbon atoms and a hydrogen atom. Where the hydrogen atom is missing, the carbon atom may bond to a fourth carbon atom in an adjacent thread. This bonding contrasts with the hexagonal carbon lattices found in buckyballs, carbon nanotubes and graphene. In these materials, electron orbitals from each carbon atom are shared between just three other carbon atoms.” It is interesting to note that Penn State University has a National Science Foundation Center for Nanothread Chemistry.  There should be some interesting research coming from this new Center.

Medicine is moving into the nano realm to study and obtain insights about amyloid plaques [Ref. 6].  These amyloid plaques are characteristic of neurodegenerative diseases.  (Diseases like Parkinson’s and Alzheimer’s.)  These plaques are abnormal aggregates that have been linked to numerous diseases.  The goal of the research was to understand the structure of the plaques.  In order to accomplish their study, it required for the development of a new aspect of microscopy.  Their “super” resolution microscopy involves the latest in high resolution equipment with the addition of a dual channel polarized fluorescence light.  With their invention, they are able to observe the working of the molecules interacting with the plaques. 

There is the annual SEMICon West conference occurring next month (July).  This year it is virtual.  There will be a number of presentations on the issues/challenges as semiconductor devices have to overcome as the dimensions go lower into the single digit nanometers.  This is one area where nanotechnology is very much in the forefront of new developments.

References:

  1. https://apps.who.int/gpmb/assets/annual_report/GPMB_annualreport_2019.pdf
  2. https://www.wsj.com/articles/the-lancets-politicized-science-on-antimalarial-drugs-11591053222?mod=hp_opin_pos_3
  3. https://www.washingtontimes.com/news/2020/may/9/covid-19-puts-spotlight-science-scientists-often-l/
  4. https://physicsworld.com/a/new-material-could-be-used-to-make-a-liquid-metal-robot/?
  5. https://physicsworld.com/a/diamond-nanothreads-could-beat-batteries-for-energy-storage-theoretical-study-suggests/?
  6. https://physicsworld.com/a/super-resolution-microscopy-reveals-nanoscale-details-of-amyloid-protein-structures/?

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Research Impacts at the End of the Great Shutdown

As the world starts to come out of the Covid–19 shutdown, there are many things that will be required for research organizations to address prior to beginning their research again. Businesses have a similar but different process that needs to be completed as the organizations come out of the Great Shutdown. There are opportunities to reevaluate processes and procedures during the restart.

The items that need to be addressed from the research perspective include the workforce, equipment maintenance and calibration, material purity and integrity, and the validity of the most recent research. The initial consideration will include any new rules, regulations, and procedures the overall organization has developed and required to be implemented.  The challenge will be that all of these things need to be accomplished simultaneously. This is one of those times when a fast start may require additional assistance from recently retired personnel or external experts.

The workforce has several components that need to be addressed. The first one is the question of whether all personnel will be returning to the organization. It is possible that those not returning could have had a serious or deadly effect of Covid-19, still be recovering, found a new position, or have decided not to return to work until some later time. It is obvious that the new people who would need to be employed to replace people no longer available will require training. The returning people will need to go through a refresher training since it has been three months or more since they last use the equipment or processes, they will be working on. In addition, there may be regulations on social distancing that require changes in the workplace.

The equipment maintenance and calibration are an important part of any research effort. Since it has been months that the equipment has been non-operating, the equipment needs to have a thorough maintenance update. (I recall returning from a two-week shutdown to find that several of our wire binders had rust on parts of the mechanism. The temperature and humidity controlled rooms keep a level of moisture in the atmosphere all the time. We had to fix that before we can begin operating again.) After the equipment is up and running it will need to be calibrated. Since it has been months since its last operation, the equipment calibration should be the more thorough version to ensure the equipment is functioning properly.

While one normally does not think too much about the material purity or liquid contamination, these could be issues do to the long storage without usage. In previous blogs I have mentioned things like changing characteristics during shipment due to exposure to air. Liquids have the potential for dilution or contamination, which would change their characteristics when used in various processes. This requires some additional time to ensure the material you think you have is the material you actually have.

The last of these major points is the need to validate the research that was being done at the time of the Great Shutdown. Research that was not complete when the event happened needs to be redone from the very beginning. Research that had been completed shortly before the Great Shutdown needs to be replicated to ensure that the new experiments produces the same results as prior to the shutdown. The purpose of this extra effort is to ensure that something else in the workplace environment did not change and create an impact on the results that were obtained.

So, the real challenge is do everything at once and to do it is accurately as possible. In many cases the items will be done sequentially which will extend out the time for the completion of the research. Another portion of this time duration of lost research time is that it probably has a serious impact on the funds that were available for the research. This is one of the times in an organizations history that leading the way provide significant benefits. Being among the first, there are opportunities to pick up seasoned employees with skill levels that are greatly needed. Those organizations that start later may not have as wide a selection of skilled workers to choose from.

There are many more details that could be added to the startup of the research along with the actual startup of business. This could be a time to look at information flow, equipment priorities, hierarchical structure, equipment needs, and other items that would enable more accurate and faster research results. There will be strong competition within organizations for additional funding, so those who are prepared and move quickly will have an advantage. Good luck and God’s speed.

I do not provide an explicit email address due to that email address becoming overloaded with spam and advertising.  I can be reached via email: “ideas at nano-blog dot com”.  Replace the “at” and “dot” with the appropriate symbols. 

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Scientific Integrity and COVID-19

I’ve written about validating scientific findings previously.  With the current COVID-19 (coronavirus) situation, there have been numerous published claims of various “facts”, which are based on models.  It was only a couple of months ago that the news carried projections of 8 billion people being infected and 80 million people dying.  That later number was reduced to 40 million.  In the US, there were projections of up to 3 million people in the United States dying, which number has been continuously reduced to possibly a maximum of 200,000, but with a possibility of the number being much lower.  The current number of reported deaths is just over 60,000 as I write this blog.

The “facts” two months ago were 80 million worldwide would die, and now that number is currently at 226,882 world-wide who have died (updated April 30, 2020) with a projected total to be in the mid to upper 100,000s.  This current trend indicates that the total number will be less than 1% of the original projection!  What happened?  There are a lot of questions that need to be answered, but that needs to be done by the developers of the model. 

The issue that will be addressed below is why models and the subsequent results need to be understood in order to correctly explain what the “facts” presented actually mean.

First, the information provided as “facts” were not “facts” but projections based on someone’s model of the situation.  A comment years ago by a friend, Professor Bob Shannon of Texas A&M explained it well.  “All models are WRONG, some are useful!”   A strong statement, which we will explore.  

Why are all models wrong?  The answer is that models are based on assumption.  (I have spent considerable time working in modeling.) The model is only as correct as the mathematical description of the object being evaluated, the accuracy of the assumptions being made, the inclusion of all the key variables, and an estimate of the probably of the variables occurring.  Usually models are built, tested, modified, tested again, and finally run multiple times over a set of probabilities.  The resultant answers yield a possible projection with a probability range.  There are usually results that provide the extremes as well as the most probable.  Therefore, the ANSWER is not a single number but a variable with a probability range based on certain assumptions.  Notice the word “assumptions”, it is plural.  The results of the model are only as good as the assumptions.  If you do not know the assumptions, you are unable to evaluate the results from the model.  In addition, models need to be improved as the analysis continues.  This is why it is called modeling.  There are some suggestions that the basic virus impact model has not changed. [Ref. #1]  That in itself is unusual.  Models need to be continually updated to reflect learning from earlier versions.

A commentary by Holman W. Jenkins, Jr. [Ref. #2] provides thoughts about the media not being able to understand multivariate.  This is the fact that things are not simple “if A, then B”.  A short version of this is: “When it rains, Jack always wears a hat”.  Does this imply that Jack wearing a hat causes it to rain?  Of course not.  But there are other variables.  Does Jack need to keep his head covered due to a skin problem?  Does Jack always wear a hat rain or shine?  This is simple example.  But, when reporting reduces a story to a single number, it loses the contributing factors.  A better understanding of how models work is required to be able to accurately report on it.

Yes, there is a need to evaluate situations that may cause a singularity – also called a black swan event.  At one-time, black swans were considered fiction, then people found one.  It was rare at the time.  Now they are not that rare.  Recently, the 100-foot rogue waves were first considered fiction and then black swan events.  Thanks to satellite imaging, we now know that they happen relatively often is certain part of the world with certain conditions.  The point being that looking at the results of a model, one needs to consider the possibility of such event, but not use that as the final answer.  Is it possible that 8 billion of the current 8.8 billion people could get the virus?  A 91% world infection rate?  Possibly yes, but that would not be the most probable and require a significant reevaluation of the modeling assumptions. 

What we, as the public, need to hear and understand is what the assumptions were in developing the models.  The first model is what is the total impact and how is it spread over time.  The second model is what is being proposed and what is that impact.  The concern on the current situation that required governmental interaction was the potential for a huge number of cases that would overwhelm the medical system.  By using a distancing model of 6 feet and a requirement of sheltering in place, the rate of infection is slowed and occurs over a longer period so the medial facilities would not be overwhelmed.  It is not indicating that the fatality rate is lower due to these regulations.  It has only been delayed.  If a vaccine is created, it will lower the fatality rate.  To be presenting anything otherwise is an indication of not understanding what the models are saying.  Large number projections may get people nervous and provide revenue for media, but the large number projections end up forcing the improper allocation of resources.      

The Mayo Clinic responded to the projections that the COVID-19 would require major resource allocation.  This resulted in the cessation/postponement of elective surgeries, cancer treatments, and other related medical procedures.  This large projected number of serious ill people did not happen.  The result was the Mayo Clinic is furloughing and/or giving pay cuts to about 1/3 of its 70,000 employees. [Ref. #3] This does not include the impact on related, externally contracted workers.  And, that does not even address the impact on the patients who were unable to have their procedures. 

Could all of this over allocation of resources be based on the lack of knowledge of understanding what is involved is establishing guidance based on unknowns in models?  One needs to know what is involved in the assumptions, variables, and probabilities.  After the models are run, there is a final decision.  Does the answer make sense, or could there be elements missing or misstated?  91% of the world being infected, raises a very serious question about the validity of the model with me. 

If the news media responds to analyses with single number answers, when these answers are not accurate, can there be any guaranty of developing a true understanding of the problem?  I doubt it.  The consequence of this type “factual presentation” is that the general public loses trust in any statements that are published.  With that is also a loss of confidence in leadership.  Scientific facts need to be presented accurately with the assumptions accompanying the results.   Integrity in every step of the entire process is required.

References:

  1. https://www.wsj.com/articles/curve-crushing-11587753699?cx_testId=3&cx_testVariant=cx_4&cx_artPos=1#cxrecs_s
  2. https://www.wsj.com/articles/the-media-vs-flatten-the-curve-11588113213?mod=hp_opin_pos_2
  3. https://kttc.com/2020/04/10/mayo-clinic-announces-temporary-furloughs-salary-reductions-for-some-employees/

I do not provide an explicit email address due to that email address becoming overloaded with spam and advertising.  I can be reached via email: “ideas at nano-blog dot com”.  Replace the “at” and “dot” with the appropriate symbols. 

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A Time of Turmoil and a Time of Opportunity

As this month’s blog is being written, the US has a “shelter-in-place” directive that has been extended through the end of April.  There are many reports of possible medical treatments that may mitigate the current Covid-19 virus.  Most of the results are anecdotal and have not been vigorously tested.  The scientific/medical process is long and involved requiring multiple trials to prove something works.  I mention this because, the information that I write about are usually one of a kind reports.  That is why references are provided for the reader to investigate further.

While not strictly “nano”, phytomining is a very interesting concept that works with small metal particles.  Phytomining is the process of employing “hyper-accumulating” plants to extract metals from the ground. [Ref. 1]  There are a number of plants, with over 700 known, that have roots that extract metal from the ground.  There is a story that people, who understand the specific plants that grow locally, can determine areas that have gold in the soil.  The referenced article describes an experiment on a plot of land in a rural village on the island of Borneo.  Every six month, the farmer cuts off about a foot on new growth.  The plant cutting can be either squeezed to release the metal or burned to obtain the metal.  After purification the resultant material is nickel citrate.  This leads to the term phytomining or agromining.  Is this a possible means of obtaining metals that are in short supply bur needed for modern society?

Nanoparticles may be successful in targeting the most dangerous of prostate tumors. [Ref. 2] Some observations have suggested that tumors with high nerve densities might grow significantly faster and spread more rapidly than tumors with low nerve densities.  Current research has challenges in identifying the different densities.  The ability to identify nerve density would provide the ability to locate the more aggressive tumors.  That is currently difficult with existing MRI techniques since tumors with dense networks can closely resemble the tumors with an undeveloped nervous system.  Researchers in China have employed combining iron oxide with a nerve binding peptide NP41.  24 hours after injection of the contrast agent material with the iron oxide particles, the high density tumors are identifiable with an MRI scan.  This work has not been advanced to the stage where it can be tested on humans.  It seems to be promising for more than prostate tumors.

I do not normally cover specific products, however, when something seems intriguing, I will provide some thoughts.  These are initial thoughts and not any recommendations for or against a product.  There is a product in the early stages of marketing that employs 60nm particles that act a capacitors (nanocapacitors).  [Ref. 3]  The explanation is that this concept was developed as part of a leading-edge antenna investigation.  Built as an appliable, bandage type device, it contains a substrate, a layer of nanocapacitors, and a carrier layer.  The carrier layer contacts the skin where there is pain.  The contention is that the nanocapacitors interfere (?) or mitigate the electrical signals the body is transmitting from the area of pain.  Does it work?  I have not tired it, so I can not issue a judgment.  The concept seems plausible.  Are there potential issues?  There could be.  It depends on what the nanomaterials are.  At the 60nm size, the properties should be very similar to the bulk material properties.  The size of the particles probably has a specific relationship to the frequency of the signal being mitigated.  The only issue that might be possible is that if the wearer employed the device to mitigate pain and performed an action that increased the severity of the source of pain.  Time will tell on this.   

These are interesting times we live in.

References:

  1. https://www.nytimes.com/2020/02/26/science/metal-plants-farm.html?utm_source=pocket-newtab
  2. https://physicsworld.com/a/nanoparticles-target-the-most-dangerous-prostate-tumours/?
  3. https://www.indiegogo.com/projects/kailo-the-future-of-pain-relief#/  Scroll down to the section that starts “your body is an electrical system” for more detail on the concept.

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Progress and Concerns

Additional information related to last month’s blog.  Single layer technology advances from the DoE’s Argonne National Laboratory have moved the Molecular Layer Etching to the atomic level. [Ref. 1] Argonne Labs have been employing Atomic Layer Etching (ALE).  Just as ALD can be employed to create single layers on a substrate, ALE can be employed to remove atomic layers.  Their work also established a relationship between the reaction temperature and the rate of material removal.  (There is a post by Karsten Arts of Eindhoven University of Technology [Ref. 2] that provides significant detail on plasma assisted ALD and thin film uniformity.)  The claim by researchers at Argonne is that this work may provide a means of creating and controlling nanomaterial geometries with the possibility of creating a means of extending Moore’s Law.  As has been stated in a number of blogs, the development of new tools or creating means to extend the usage of existing tools will provide the means of creating new materials that have properties unknown to us at this time. 

Moving to at different subject, the need for scientific integrity and reproducible results is critical for the advancement of science.  It is also true in other fields.  In a report from the University of Texas at Austin, McCombs School of Business [Ref.3], the topic of using standard algorithms to develop corporate business reports is compared to the traditional approach employed by businesses.  One key observation was that depending on the manner in which the company employed the data (or only a portion of the data), the results of the businesses could change.  Interestingly, the independent observer preferred the reports generated by the management over the algorithm approach.  The report states that the observers preferred the business developed report due to the “positive” spin on explaining the numbers. 

This brings us back to scientific research where the results are promising but there is insufficient information about the original hypothesis, or the experiment procedure developed to prove/disprove the hypothesis.  A few years ago, I covered the study that found of just over 100 published reports of scientific discovery, over 80% of the results were not able to be duplicated – even by the original researcher.  Granted, that many cases, the research area is so new, that expertise of independent researchers for the review may not fully comprehend what is being done without the ability to observe the experiment.  This becomes more of an issue as the nanoscale development moves to smaller and smaller dimensions.  The equipment is normally expensive and scarce.  Time to use the equipment is strictly allocated.  Consequently, the researcher must provide details of the testing and detailed results that are comprehensive.  Removing some results need to be explained whether due to instrumentation irregularities or equipment malfunction or bad sample preparation.  Without details the integrity of the results must be suspect.  A single instance is insufficient.  If one looks at the range of probabilities for an occurrence of a sample size of one, and there is an “n-1” in the denominator, the answer is meaningless.

As the development of materials starts to incorporate more and more single atomic layer materials, the critical nature of reproducible results is necessary.  Scientific integrity has to exist.

References:

  1. https://www.anl.gov/article/new-argonne-etching-technique-could-advance-the-way-semiconductor-devices-are-made
  2. https://www.atomiclimits.com/2020/02/08/basic-insights-into-ald-conformality-a-closer-look-at-ald-and-thin-film-conformality/
  3. https://medium.com/texas-mccombs/to-remove-corporate-bias-let-algorithms-summarize-earnings-47a8055b8d53

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Is that all there is?

With apologies for using the title of a Peggy Lee song from the 70s, this reference is to nanotechnology.  There are continually more interesting findings as researchers move into smaller and smaller particle sizes.  The question really is what happens when the ability to work at sizes as single digit nanometer particles and smaller becomes practical.  To some extent, research is already at this point.  What new properties will become known?

There has been concern that the absorption of heave metals can have a detrimental effect on the human body by becoming a cumulative toxic.  Gold nanoparticles have been employed in various cancer cure Efforts since the early 2000s.  A recent report [Ref. 1] indicates that gold, chemically inert, does not remain intact within cellular structures.  In work done by researchers at the University of Paris, Sorbonne University, and the University of Strasbourg has revealed that gold nanoparticles ranging from 4nm to 22nm indicates these particles do not remain unchanged.    They observed a transformation of the nanoparticles into leaf shaped structures.  These finding may provide additional avenues of investigation for determining the means which the human body metabolizes the particles.  This could change the overall evaluation of potential toxicity.

As mentioned in last month’s blog, researchers have been able to strengthen the structure of silver without diminishing it conductive properties by “implanting” copper atoms at defect along the grain boundaries of the silver.  The maximum strengthening appears to occur when the grain boundaries are 7nm apart. [Ref. 2]

There has been a number of articles on two-dimensional materials, like graphene.  An article in Nature Electronics [Ref. 3] describes the development of heterostructures form by stacking layers of different two-dimensional materials that are possible due to Van der Waals forces.  This particular application create memristors with good thermal stability. 

This bring the discussion to the progress in Atomically Precise Manufacturing (APM).  From Wikipedia, “APM is the production of materials, structures, devices, and finished goods in a manner such that every atom has a specific location relative to the other atoms …” [Ref. 4]  In 2017, the American Chemical Society has a report [Ref. 5] that indicates over 100 molecules of noble metals have been created and are able to de manufactured.  The molecules demonstrate different properties that are different from the nanomaterials.  The research effort has grown to the point where there is a conference on Atomically Precise Nanochemistry. [Ref. 6]

So, Nanotechnology is not the bottom.  There is also work being on electron spin in the quantum realm.  The one consideration that needs to move forward as the APM and other atomic level research progresses in the issue of “safety”.   The development of a “white” paper on the challenges for the manufacture, storage, and handling of these even smaller particles has been initiated with the anticipated release of the recommendation late in 2020.  This effort will be a complementary effort to the existing Nano-Safety “white” paper from 2007. [Ref. 7]

References:

  1. https://physicsworld.com/a/gold-nanoparticles-inside-cells-are-not-inert-say-researchers/?utm_medium=email&utm_source=iop&utm_term=&utm_campaign=14290-45008&utm_content=Title%3A%20Gold%20nanoparticles%20inside%20cells%20are%20not%20inert%2C%20say%20researchers%20%20-%20Editors_pick&Campaign+Owner=
  2. https://www.uvm.edu/uvmnews/news/inventing-worlds-strongest-silver 
  3. https://www.nature.com/articles/s41928-018-0021-4
  4. https://en.wikipedia.org/wiki/Atomically_precise_manufacturing
  5. https://pubs.acs.org/doi/abs/10.1021/acs.chemrev.6b00769
  6. https://www.grc.org/atomically-precise-nanochemistry-conference/2020/
  7. http://www.tryb.org/a_white_paper_on_nano-safety.pdf

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Another Year of Progress (?)

As always when reflecting over a year that is ending, there is good news and there is bad news.  We’ll start with the good.  A lot of technology is being created.  As mentioned last month, new material properties are being created.  The one that I find the most fascinating is the creation of transparent wood!  This material was developed at the KTH Royal Institute of Technology in Stockholm. [Ref. 1] The wood is capable of both storing heat and being transparent, although the transparency becomes translucent as the heat is released.  The figure shows the fully transparent wood on the left and the translucent heat release wood on the right. 

In order to manufacture the wood, the researchers took balsa wood and removed its lignin (provides strength and color) and added acrylic into the remaining tissues filling the empty space remaining from the removal of the lignin and hollow spaces that carry water within the tree.  This produced the structure that restored the strength lost by the removal of the lignin and provided the optical properties.

Another report [Ref 2] describes increasing the strength of silver conductor by introducing very sight amounts of copper.   Their 42% increase in strength is due to their discovery of a new mechanism that works at the nanoscale.  They started with the premise that all metals have defects, which leads to undesirable qualities.  To compensate for these changes, many have solved that issue by creating alloys to make materials stronger, which tends to reduce electrical conductivity.   The team, including researchers from the University of Vermont, Lawrence Livermore National Lab, Ames lab, Los Alamos Nations Lab, and UCLA, began with the fact that as a material size is reduced to the size of a crystal, the material gets stronger. (Hall-Petch relation).  This relation no longer holds when the material is in the 10s of nanometers.  The boundaries between grains becomes unstable and can move.  (Significantly more detail is in the referenced article.)  Introduction of copper atoms, which are slightly smaller than silver atoms, allows the copper atoms to move into defect areas in the grain boundaries.  The team reported the maximum strength is achieved with boundaries that are 7 nanometers apart. 

The future of semiconductors is continuing down the path of continual size reduction.  The next release of the Roadmap will provide the requirements for individual structures that will be measured in tenths of nanometers.  While that is still years away, the fact that such structures are being contemplated implies the development of equipment that will be able to increase our ability to evaluate phenomena in the single digit nanometer and and below.

There appears to great things happening, so what is the bad news.  Unfortunately, the bad news is that the true application of the scientific method is being compromised occasionally.  I am not going to pick one specific study.  There have been retractions from researchers when others in the field have pointed out that their investigations have produced data that was removed in the final determination of the findings.  This is nothing new, but the increase in retractions has been growing since the mid 1990s. [Ref. 3] While the referenced article points out that retractions are not all bad, the increase in fabricated results or falsification has risen along with the rise in retractions.  We must have trust in research that is reported.

References:

  1. https://www.theguardian.com/environment/2019/apr/03/scientists-invent-transparent-wood-in-search-for-eco-friendly-building-material
  2. https://www.uvm.edu/uvmnews/news/inventing-worlds-strongest-silver  
  3. https://alumni.berkeley.edu/california-magazine/just-in/2016-03-16/retraction-action-science-fraud-more-retractions-could-be

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