Category Archives: Science: Physics, Astronomy, etc.

C-PAPs do not help A-Fib, and seem to make heart health worse.

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In this blog-post, I’d like to report on the first random study of patients with Atrial fabulation, A-Fib, and sleep apnea, comparing the health outcome of those who use a C-PAP, a “Continuous Positive Airway Pressure” device, to the outcome those who do not. The original study was published in May, 2021 (read it here) in the American Journal of Respiratory and Critical Care Medicine. The American Journal, Pulmonary Advisor published a more-popular version here.

As a background, if you are over 65 and overweight, there is a 25% chance or so that your heart rate will begin to surge semi-randomly, and that it will flutter. This is Atrial fabulation, A-Fib. It tends to get worse and tends to lead to heart attacks and strokes. People with A-fib tend to be treated with drugs, aspirin, warfarin, beta blockers, and anti arrhythmics. They also tend to be prescribed a C-PAP because overweight, older folks tend to snore and wake up a lot during the night (several times per hour: apnea).

A C-PAP definitely stops the snoring and the Apnea, and the assumption was that it would help your heart as well, if only by giving you a better night’s sleep. As it turns out, the C-PAP seems to decrease heart health — significantly.

For this study, adult patients between 18 and 75 years old diagnosed with paroxysmal A-Fib (that’s occasional AF) were screened for moderate to severe sleep apnea. Those who agreed to participate were randomly assigned to either a treatment of C-PAP plus usual care (drugs mostly) or just usual care for the next 5 months. Of the 109 who enrolled in the study, 55 got the C-PAP plus usual care, 54 got usual care alone. The outcome was that there were 9 serious, adverse heart events (strokes and heart attacks); 7 were in the C-PAP group.

The CPAP pressure was, on average, 6.8 cm H2O; mean time of use was 4.4±1.9 hours per night. The C-PAPs did their jobs on the apnea too, reducing residual apnea-hypopnea to 2.3±1.9 events per hour for those in the C-PAP group.

There was a non-statistically significant reduction is AF among the C-PAP group. They reduced their time in AF by 0.6 percentage points compared to the control group  (95% CI, -2.55 to 1.30; P =.52). That not a statistically significant difference, and is most likely random.

There was a statistically significant decrease in heart health, though. A total of 7 serious adverse events occurred in the C-PAP group and only 2 in the control group. A total of 9 is a relatively small number of events, but there is a strong statistical difference between 7 and 2.

The authors conclude: “CPAP treatment does not seem to reduce or prevent paroxysmal AF.” They should also have concluded that it reduced heart health with a statistical confidence of ~82%: (1-2(36+10)/512) =82%. See more on this type of statistics.

A possible explanation of why a C-PAP would would make heart health worse is an outcome of the this recent sleep study (link here). It appears that the C-PAP helps restore breathing, but by doing so, it interferes with a mechanism the body uses to deal with A-fib. It seems that, for people with A-Fib, their bodies use breathing stoppages to get their heart back into rhythm. For these people, many of their breathing stoppage are not obstructive, but a bio-pathway to raise the CO2 level in the blood and thus regulate heart rate. The use of a C-PAP prevents this restorative mechanism and this seem to be the reason it is destructive to the heart-health of patients with A-fib. On the other hand, a C-PAP does improve the sleep those patients whose apnea is obstructive. It seems to me that sleep studies should do a better job distinguishing the two causes of apnea. C-PAPs seem counter-indicated for patients with A-fib.

Robert Buxbaum, March 30, 2022. I was diagnosed with apnea and A-Fib some years ago. The sleep doctor prescribed a C-PAP and was adamant that I had to use it to keep my heart healthy. There were no random studies backing him up or contradicting him until now.

Deadly incurable viruses abound: The plagues to come.

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As we discuss the effectiveness of the various COIVD vaccines, and ask if we will need another booster in a year, this time for the delta variant, or epsilon, it’s worth noticing that none of these is that deadly, especially if you’ve had a previous version. There are far worse viruses out there, like Ebola-Zaire, for example. This virus kills 60-90% of the people infected, typically by causing the body’s connective tissue to dissolve. Now that’s a deadly virus; imagine an ebola pandemic.

We live surrounded by many really deadly viruses, most of them incurable. In general our protection from them is that they usually show a slow infection rate or a slow progress to death. Drug resistant leprosy is one of these. Here’s the beginnings of a list of deadly viruses we could worry about: Lassa, Rift Vally, Oropouche, Rocio Q Guanarito, VEE, Marburg, Herpes B, Monkey Pox, Dengue, Chikunguanya, Hantavirus, Machupo, Junin, Rabies-like Mokola, drug-resistant leprosy, Duvenhage, LeDantec, Kyasanur, Forest Brain virus, HIV-AIDs, Simliki, Crimean-Congo virus, Sindbis, O’nyongnyong, Sao Paulo, SARS, Ebola Sudan, Ebola Zaire, Ebola Reston, Mid-East Respiratory (MERS), Zika, Delta-COVID. (I got 2/3 of this list from a 1993 book called “The Hot Zone” about the first US outbreak of Ebola — Washington DC in 1989 — a good book, worth a read).

Ebola is a string-like virus with loops. It causes your body to dissolve and bleed out from every pore. The strings form crystals that are virtually immortal.

As an ilk, these viruses are far older than we are, older than the first cellular creatures, and far tougher. They are neither dead nor alive, and can last for years generally without air, water or food if the temperature is right. Though they do not move on their own, nor eat in any normal sense, they do reproduce, and they do so with a vengeance. They also manage to evolve by an ingenious sexual mechanism. In a sense, they are the immune system of the earth, protecting the earth from man or any other invasive life form. We humans have only survived the virus for 100,000 years or so. Long term, the viruses are likely to win.

Zika is a ball-shaped virus. Incurable, it causes encephala. Ball-viruses are not as immortal as string viruses. COVID is a ball virus with spikes, a crown virus.

Some viruses are string shaped; Marburg and Ebola are examples. Such viruses can crystalize and live virtually forever on dry surfaces. Other viruses are ball-shaped, COVID and Zika, for example. These are more easily attacked on surfaces, e.g. by iodine. They become inactive after just a few minutes in air– and are killed instantly by iodine, alcohol, bleach, or peroxide.

Most viruses enter by cuts and body fluids. This is the case with AIDS and herpes. Others, like measles, shingles, and Zika, enter by way of surfaces and the hands. Virus-laden droplets collect on surfaces and are brought to a new host when the surface is touched and hand-transported to the nose or eyes. A few viruses, like SARS, Ebola, and COVID-19 can enter the body by breathing too. I’ve collected some evidence in favor of Iodine as a surface wipe, a hand wipe and as mouthwash in this previous essay.

Dr. Robert E. Buxbaum, November 3, 2021. The US has three facilities where they deal with the most deadly, contagious viruses. One is in Washington DC; they had leak in 1989, a part of the ebola outbreak. China has only one such facility, in Wuhan, China. It’s one block from where the COVID-19 outbreak supposedly originated. Have a nice day.

Low temperature hydrogen removal

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Platinum catalysts can be very effective at removing hydrogen from air. Platinum promotes the irreversible reaction of hydrogen with oxygen to make water: H2 + 1/2 O2 –> H2O, a reaction that can take off, at great rates, even at temperatures well below freezing. In the 1800s, when platinum was cheap, platinum powder was used to light town-gas, gas street lamps. In those days, street lamps were not fueled by methane, ‘natural gas’, but by ‘town gas’, a mix of hydrogen and carbon monoxide and many impurities like H2S. It was made by reacting coal and steam in a gas plant, and it is a testament to the catalytic power of Pt that it could light this town gas. These impurities are catalytic poisons. When exposed to any catalyst, including platinum, the catalyst looses it’s power to. This is especially true at low temperatures where product water condenses, and this too poisons the catalytic surface.

Nowadays, platinum is expensive and platinum catalysts are no longer made of Pt powder, but rather by coating a thin layer of Pt metal on a high surface area substrate like alumina, ceria, or activated carbon. At higher temperatures, this distribution of Pt improves the reaction rate per gram Pt. Unfortunately, at low temperatures, the substrate seems to be part of the poisoning problem. I think I’ve found a partial way around it though.

My company, REB Research, sells Pt catalysts for hydrogen removal use down to about 0°C, 32°F. For those needing lower temperature hydrogen removal, we offer a palladium-hydrocarbon getter that continues to work down to -30°C and works both in air and in the absence of air. It’s pretty good, but poisons more readily than Pt does when exposed to H2S. For years, I had wanted to develop a version of the platinum catalyst that works well down to -30°C or so, and ideally that worked both in air and without air. I got to do some of this development work during the COVID downtime year.

My current approach is to add a small amount of teflon and other hydrophobic materials. My theory is that normal Pt catalysts form water so readily that the water coats the catalytic surface and substrate pores, choking the catalyst from contact with oxygen or hydrogen. My thought of why our Pd-organic works better than Pt is that it’s part because Pd is a slower water former, and in part because the organic compounds prevent water condensation. If so, teflon + Pt should be more active than uncoated Pt catalyst. And it is so.

Think of this in terms of the  Van der Waals equation of state:{\displaystyle \left(p+{\frac {a}{V_{m}^{2}}}\right)\left(V_{m}-b\right)=RT}

where V_{m} is molar volume. The substance-specific constants a and b can be understood as an attraction force between molecules and a molecular volume respectively. Alternately, they can be calculated from the critical temperature and pressure as

{\displaystyle a={\frac {27(RT_{c})^{2}}{64p_{c}}}}{\displaystyle b={\frac {RT_{c}}{8p_{c}}}.}

Now, I’m going to assume that the effect of a hydrophobic surface near the Pt is to reduce the effective value of a. This is to say that water molecules still attract as before, but there are fewer water molecules around. I’ll assume that b remains the same. Thus the ratio of Tc and Pc remains the same but the values drop by a factor of related to the decrease in water density. If we imagine the use of enough teflon to decrease he number of water molecules by 60%, that would be enough to reduce the critical temperature by 60%. That is, from 647 K (374 °C) to 359 K, or -14°C. This might be enough to allow Pt catalysts to be used for H2 removal from the gas within a nuclear wast casket. I’m into nuclear, both because of its clean power density and its space density. As for nuclear waste, you need these caskets.

I’ve begun to test of my theory by making hydrogen removal catalyst that use both platinum and palladium along with unsaturated hydrocarbons. I find it works far better than the palladium-hydrocarbon getter, at least at room temperature. I find it works well even when the catalyst is completely soaked in water, but the real experiments are yet to come — how does this work in the cold. Originally I planned to use a freezer for these tests, but I now have a better method: wait for winter and use God’s giant freezer.

Robert E. Buxbaum October 20, 2021. I did a fuller treatment of the thermo above, a few weeks back.

Exercise helps fight depression, lithium helps too.

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With the sun setting earlier, and the threat of new COVID lockdowns, there is a real threat of a depression, seasonal and isolation. A partial remedy is exercise; it helps fight depression whether you take other measures not. An article published last month in the Journal of Affective Disorders reviewed 22 studies of the efficacy of exercise, particularly as an add-on to drugs and therapy. Almost every study showed that exercise helped, and in some studies it helped a lot. See table below. All of the authors are from the University of British Columbia. You can read the article here.

From “Efficacy of exercise combined with standard treatment for depression compared to standard treatment alone: A systematic review and meta-analysis of randomized controlled trials.” by JacquelineLee1 et al.In virtually every study, exercise helps fight depression.

For those who are willing to exercise, there are benefits aside from mental health. Even a daily walk around the block helps with bone strength, weight control, heart disease, plus the above mentioned improvement in mood. More exercise does more. If you bicycle without a helmet, you’re likely to live longer than if you drive.

For those who can’t stand exercise, or if exercise isn’t quite enough to send away the blues, you can try therapy, medication, and/or diet. There is some evidence that food that are high in lithium help fight depression. These food include nuts, beans, tomatoes, some mineral waters, e.g. from Lithia springs, GA. The does is about 1/100 the dose given as a bipolar treatment, but there is evidence that even such small doses help. Lithium was one of the seven ingredients in seven up — it was the one that was supposed to cheer you up. See some research here.

Robert Buxbaum, October 7, 2021.

Weird thermodynamics near surfaces can prevent condensation and make water more slippery.

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It is a fundamental of science that that the properties of every pure one-phase material is totally fixed properties at any given temperature and pressure. Thus for example, water at 0°C is accepted to always have a density of 0.998 gm/cc, a vapor pressure of 17.5 Torr, a viscosity of 1.002 centipoise (milliPascal seconds) and a speed of sound of 1481 m/s. Set the temperature and pressure of any other material and every other quality is set. But things go screwy near surfaces, and this is particularly true for water where the hydrogen bond — a quantum bond — predominates.

its vapor pressure rises and it becomes less inclined to condense or freeze. I use this odd aspect of thermodynamics to keep my platinum-based hydrogen getter catalysis active at low temperatures where they would normally clog. Normal platinum catalysts are not suitable for hydrogen removal at normal temperatures, eg room temperature, because the water that forms from hydrogen oxidation chokes off the catalytic surface. Hydrophobic additions prevent this, and I’d like to show you why this works, and why other odd things happen, based on an approximation called the  Van der Waals equation of state:

{\displaystyle \left(p+{\frac {a}{V_{m}^{2}}}\right)\left(V_{m}-b\right)=RT} (1)

This equation described the molar volume of a pure material, V_{m}, of any pure material based not the pressure, the absolute temperature (Kelvin) and two, substance-specific constants, a and b. These constants can be understood as an attraction force term, and a molecular volume respectively. It is common to calculate a and b from the critical temperature and pressure as follows, where Tc is absolute temperature:

{\displaystyle a={\frac {27(RT_{c})^{2}}{64p_{c}}}}, {\displaystyle b={\frac {RT_{c}}{8p_{c}}}.} (2 a,b)

For water Tc = 647 K (374°C) and 220.5 bar. Plugging in these numbers, the Van der Waals gives reasonable values for the density of water both as a liquid and a gas, and thus gives a reasonable value for the boiling point.

Now consider the effect that an inert surface would have on the effective values of a and b near that surface. The volume of the molecules will not change, and thus b will not change, but the value of a will change, likely by about half. This is because, the number of molecules surrounding any other molecule is reduced by about half while the inert surface adds nothing to the attraction. Near a surface, surrounding molecules still attract each other the same as before, but there are about half as many molecules at any temperature and pressure.

To get a physical sense of what the surface does, consider using the new values of a and b to determine a new value for Tc and Pc, for materials near the surface. Since b does not change, we see that the presence of a surface does not affect the ratio of Tc and Pc, but it decreases the effective value of Tc — by about half. For water, that is a change from 647 K to 323.5K, 50.5°C, very close to room temperature. Pc changes to 110 bar, about 1600 psi. Since the new value of Tc is close to room temperature, the the density of water will be much lower near the surface, and the viscosity can be expected to drop. The net result is that water flows more readily through a teflon pipe than through an ordinary pipe, a difference that is particularly apparent at small diameters.

This decrease in effective Tc is useful for fire hoses, and for making sailing ships go faster (use teflon paint) and for making my hydrogen removal catalysts more active at low temperatures. Condensed water can block the pores to the catalyst; teflon can forestall this condensation. It’s a general trick of thermodynamics, reasonably useful. Now you know it, and now you know why it works.

Robert Buxbaum August 30, 2021

The delta variant is no big deal if you’re young or vaccinated.

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The toll of COVID-19 has been terrible: 660,000 dead by my count, based on excess deaths, graph below, or 620,000 according to the CDC based on hospital records. Death rates appear to have returned to pre-pandemic levels, more or less*, but folks are still getting very sick and going to the hospital, mostly for “the delta variant.”

Weekly US death rates since October 2015.

As the following chart shows, severe symptoms of COVID are now almost entirely in the old, and unvaccinated. The risk to the young and middle aged is low, but even there, vaccination helps. According to the CDC, 72.2% of the adult US population is vaccinated with at least one shot. The vaccination, doesn’t prevent you from getting the delta variant nor from spreading it; it just protects from the most serious consequences of the disease. It seems a previous infection has the same effect, though less so.

Vaccination helps prevent hospitalization – at all ages (Israeli data)

If you’re over 60 and unvaccinated, I recommend getting vaccinated with at least one shot; the inconvenience and side-effects are few, and the benefit is large. The second shot seemswothshile too, and for all I know a third will too. Sooner or later there is a diminishing return. The benefit of masks seems is smaller, as I judge things. I notice that the disease is spreading at about the same rate in masked and unmasked states, and that the death numbers are as high, or higher in heavily masked, blue states as in red. New York and NJ are the top COVID death states, with Michigan not far behind. Masks seem to help, just not very much.

For those who want further advice, I can suggest dilute iodine gargle. I did this when I got a sore throat, I also suggest got a pneumonia vaccination, and take and adult aspirin every other day for COVID and heart-attack prevention. I also take a vitamin D tablet every few days.

If you wish to check my analysis, go here to get the raw data: https://gis.cdc.gov/grasp/fluview/mortality.html. Then, to calculate the COVID effect, I subtracted the weekly death rates in 2020 and 2021 from the corresponding week rates in 2019, correcting the deaths by 1%/year for population growth and aging. *I find that there are about 500 excess deaths per week, and I assume those are among the unvaccinated. If you are vaccinated, I’d worry about something else besides COVID-delta: heart attack, cancer, suicide, or Afghanistan.

Robert Buxbaum August 18, 2021. I made a video of cute iodine reactions, including the classic “iodine clock”, where I use vitamin C as as the anti-oxidant (reducing agent).

Upgrading landfill and digester gas for sale, methanol

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We live in a throw-away society, and the majority of it, eventually makes its way to a landfill. Books, food, grass clippings, tree-products, consumer electronics; unless it gets burnt or buried at sea, it goes to a landfill and is left to rot underground. The product of this rot is a gas, landfill gas, and it has a fairly high energy content if it could be tapped. The composition of landfill gas changes, but after the first year or so, the composition settles down to a nearly 50-50 mix of CO2 and methane. There is a fair amount of water vapor too, plus some nitrogen and hydrogen, but the basic process is shown below for wood decomposition, and the products are CO2  and methane.

System for sewage gas upgrading, uses REB membranes.

C6 H12 O6  –> 3 CO2  + 3 CH4 

This mix can not be put in the normal pipeline: there is too much CO2  and there are too many other smelly or condensible compounds (water, methanol, H2S…). This gas is sometimes used for heat on site, but there is a limited need for heat near a landfill. For the most part it is just vented or flared off. The waste of a potential energy source is an embarrassment. Besides, we are beginning to notice that methane causes global-warming with about 50 times the effect of CO2, so there is a strong incentive to capture and burn this gas, even if you have no use for the heat. I’d like to suggest a way to use the gas.

We sell small membrane modules too.

The landfill gas can be upgraded by removing the CO2. This can be done via a membrane, and REB Research sells a membranes that can do this. Other companies have other membranes that can do this too, but ours are smaller, and more suitable to small operations in my opinion. Our membrane are silicone-based. They retain CH4 and CO and hydrogen, while extracting water, CO2 and H2S, see schematic. The remainder is suited for local use in power generation, or in methanol production. It can also be used to run trucks. Also the gas can be upgraded further and added to a pipeline for shipping elsewhere. The useless parts can be separated for burial. Find these membranes on the REB web-site under silicone membranes.

Garbage trucks in New York powered by natural gas. They could use landfill gas.

There is another gas source whose composition is nearly identical to that of landfill gas; it’s digester gas, the output of sewage digesters. I’ve written about sewage treatment mostly in terms of aerobic bio treatment, for example here, but sewage can be treated anaerobically too, and the product is virtually identical to landfill gas. I think it would be great to power garbage trucks and buses with this. Gas. In New York, currently, some garbage trucks are powered by natural gas.

As a bonus, here’s how to make methanol from partially upgraded landfill or digester gas. As a first step 2/3 of the the CO2 removed. The remained will convert to methanol. by the following overall chemistry:

3 CH4 + CO2 + 2 H2O –> 4 CH3OH. 

When you removed the CO2., likely most of the water will leave with it. You add back the water as steam and heat to 800°C over Ni catalyst to make CO and H2. That’s done at about 800°C and 200 psi. Next, at lower temperature, with an appropriate catalyst you recombine the CO and H2 into methanol; with other catalysts you can make gasoline. These are not trivial processes, but they are doable on a smallish scale, and make economic sense where the methane is essentially free and there is no CNG customer. Methanol sells for $1.65/gal when sold by the tanker full, but $5 to $10/gal at the hardware store. That’s far higher than the price of methane, and methanol is far easier to ship and sell in truckload quantities.

Robert Buxbaum, June 8, 2021

Brown’s gas for small scale oxygen production.

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Some years ago I wrote a largely negative review of Brown’s gas, but the COVID crisis in India makes me want to reconsider. Browns gas can provide a simple source of oxygen for those who are in need. First, an explanation, Browns gas is a two-to-one mix of hydrogen and oxygen; it’s what you get when you do electrolysis of water without any internal separator. Any source of DC electricity will do, e.g. the alternator of a car or a trickle charger of the sort folks buy for their car batteries, and almost any electrode will do too (I’d suggest stainless steel). You can generate pressure just by restricting flow from the electrolysis vessel, and it can be a reasonable source of small-scale oxygen or hydrogen. The reaction is:

H2O –> H2 + 1/2 O2.

The problem with Brown’s gas is that it is explosive, more explosive than hydrogen itself, so you have to handle it with care; avoid sparks until you separate the H2 from the O2. Even the unseparated mix has found some uses, e.g. as a welding gas, or for putting in cars to avoid misfires, increase milage, and decrease pollution. I think that methanol reforming is a better source of automotive hydrogen: hydrogen is a lot safer than this hydrogen-oxygen mix.

Browns gas to oxygen for those who need it.

The mix is a lot less dangerous if you separate the oxygen from the hydrogen with a membrane, as I show in the figure. at right. If you do this it’s a reasonable wy to make oxygen for patients who need oxygen. The electrolysis cell can be a sealed bottle with water and the electrodes; add a flow restriction as shown to create the hydrogen pressure that drives the separation. The power can be an automotive trickle charger. You can get this sort of membranes from REB Research, here and many other suppliers. REB provide consulting services if you like.

In a pinch, you don’t even need the membrane, by the way. You can rely on your lungs to make the separation. A warning, though, the mix is dangerous. Avoid all sparks. Also, don’t put salt into the water. You can can put in some baking soda or lye to speed the electrolysis, but If you put salt in, you’ll find you don’t make oxygen, but will instead make chlorine. And chlorine is deadly. If you’re not sure, smell the gas. If it smells acrid, don’t use it. This is the chlorine-forming reaction.

2NaCl + 2 H2O –> H2 + Cl2 + 2NaOH

Ideally you should vent the hydrogen stream out the window, but for short term, emergency use, the hydrogen can be vented into your home. Don’t do this if anyone smokes (not that anyone should smoke about someone on oxygen). This is a semi-patentable design, but I’m giving it away; not everything that can be patented should be.

Robert Buxbaum, May 13, 2021.

The remarkable efficiency of 22 caliber ammunition.

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22 long rifle shells contain early any propellant.

The most rifle cartridge in the US today is the 22lr a round that first appeared in 1887. It is suitable to small game hunting and while it is less–deadly than larger calibers, data suggests it is effective for personal protection. It is also remarkably low cost. This is because the cartridge in almost entirely empty as shown in the figure at right. It is also incredibly energy efficient, that is to say, it’s incredibly good at transforming heat energy of the powder into mechanical energy in the bullet.

The normal weight of a 22lr is 40 grains, or 2.6 grams; a grain is the weight of a barley grain 1/15.4 gram. Virtually every brand of 22lr will send its bullet at about the speed of sound, 1200 ft/second, with a kinetic energy of about 120 foot pounds, or 162 Joules. This is about twice the energy of a hunting bow, and it will go through a deer. Think of a spike driven by a 120 lb hammer dropped from one foot. That’s the bullet from a typical 22lr.

The explosive combustion heat of several Hodgdon propellants.

The Hodgdon power company is the largest reseller of smokeless powder in the US with products from all major manufacturers, with products selling for an average of $30/lb or .43¢ per grain. The CCI Mini-Mag, shown above, uses 0.8 grains of some powder 0.052 grams, or about 1/3¢ worth, assuming that CCI bought from Hodgdon rather than directly from the manufacturer. You will notice that the energies of the powders hardly varies from type to type, from a low of 3545 J/gram to a high of 4060 J/gram. While I don’t know which powder is used, I will assume CCI uses a high-energy propellant, 4000 J/gram. I now calculate that the heat energy available as 0.052*4000 = 208 Joules. To calculate the efficiency, divide the kinetic energy of the bullet by the 208 Joules. The 40 grain CCI MiniMag bullet has been clocked at 1224 feet per second indicating 130 foot pounds of kinetic energy, or 176 J. Divide by the thermal energy and you find a 85% efficiency: 176J/ 208 J = 85%. That’s far better than your car engine. If the powder were weaker, the efficiency would have to be higher.

The energy content of various 22lr bullets shot from different length barrels.

I will now calculate the pressure of the gas behind a 22lr. I note that the force on the bullet is equal to the pressure times the cross-sectional area of the barrel. Since energy equals force times distance, we can expect that the kinetic energy gained per inch of barrel equals this force times this distance (1 inch). Because of friction this is an under-estimate of the pressure, but based on the high efficiency, 85%, it’s clear that the pressure can be no more than 15% higher than I will calculate. As it happens, the maximum allowable pressure for 22lr cartridges is set by law at 24,000 psi. When I calculate the actual pressure (below) I find it is about half this maximum.

The change in kinetic energy per inch of barrel is calculated as the change in 1/2 mv2, where m is the mass of the bullet and v is the velocity. There is a web-site with bullet velocity information for many brands of ammunition, “ballistics by the inch”. Data is available for many brands of bullet shot from gun barrels that they cut shorter inch by inch; data for several 22lr are shown here. For the 40 grain CCI MiniMag, they find a velocity of 862 ft/second for 2″ barrel, 965 ft/second for a 3″ barrel, 1043 ft/second for a 4″ barrel, etc. The cross-section area of the barrel is 0.0038 square inches.

Every 22 cartridge has space to spare.

Based on change in kinetic energy, the average pressure in the first two inches of barrel must be 10,845 psi, 5,485 psi in the next inch, and 4,565 psi in the next inch, etc. If I add a 15% correction for friction, I find that the highest pressure is still only half the maximum pressure allowable. Strain gauge deformation data (here) gives a slightly lower value. It appears to me that, by adding more propellant, one could make a legal, higher-performance version of the 22lr — one with perhaps twice the kinetic energy. Given the 1/3¢ cost of powder relative to the 5 to 20¢ price of ammo, I suspect that making a higher power 22lr would be a success.

Robert Buxbaum, March 18, 2021. About 10% of Michigan hunts dear every year during hunting season. Another 20%, as best I can tell own guns for target shooting or personal protection. Just about every lawyer I know carries a gun. They’re afraid people don’t like them. I’m afraid they’re right.

IFL Science grows up.

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I used to follow an Australian science blog, called “I Fucking Love Science.” Elise Andrew and her crew scanned the literature with a keen eye for the interesting. They regularly posted to Facebook and alerted science nerds like me to all sorts of new science bits with minimal commentary, minimal advertisements, and no politics. On average they found 6 or 8 really interesting posts, per week, generally one or two on fundamental physics, one or two on materials, one or two on biology or medicine, one or two astronomy, perhaps a chemistry post. My post about the color of the sky on Mars was ignited by a picture of the Mars sky that I saw on IFL Science — the sky was yellow, and I had just written about why the sky on earth was blue, and not green.

But, as with all quirky things, this one matured. The name changed to “IFL Science” — a change that I suspect was designed to promote sharing. There were more advertisements, and click bait — “this starlet lost a ton of weight,” “you won’t believe what this famous person’s partner looks like now,” etc. And there was politics, vaguely presented as science. Ms Andrew wrote more and more of herself, making herself into a personality whose travels and speaking tours would interest us. And there were non-science, guest bloggers too: People telling you who to vote for and more importantly who to vote against. All for the good of the world, she said, but it was her opinion, and not what I’d gone to IFL for.

The science got less technical, too and more popular. More pretty pictures and misleading headlines. Currently there is no math, no equations, no chemical diagrams. A top story of this week told of a semi-interesting approach for women with constipation — something that “would change everything.” When you click on the story, you find that women put their finger in their vagina and work out the poop that way, something called “splinting.” It’s sort of science, but not the sort that made me love science. Another top story — the top one from today is as follows:

Top story from IFL science today, Feb 28, 2021. Is there really no fuel use? No. The fuel is a battery, and the speed in 4m/s (9mph), and the plane looks nothing like this.

If you follow the links to here, it turns out that the plane (unmanned) looks nothing like this. It uses electric energy from a battery to move ionized air rearward at an efficiency far lower than with a propeller. The forward speed is 4 m/s (9 mph) and the maximum distance covered was 55m, half a Canadian football field. As presented in IFL science, it’s a misleading, non-math clickbait for something that’s interesting engineering — sort of. As for being Star Trek like, no. To move this plane, you need air.

I’m sorry, you can not make quantum mechanics for dummies. No dummy will understand it. You can make a book that’s not quantum mechanics for dummies, or a quantum book not for dummies. Just saying.

In the treatment of the work of the recent Noble laureates, IFL Science didn’t talk about the work so much as the biographies of the people, and their struggles, and that two of the people who won Nobels for their work in biology were women — for an advance related to CRISPERS– but that wasn’t science. I’d prefer to know what the advance was, and how it works. I’d prefer to figure out that these were women from their names or from the pronouns like, “she” or “her”. There was also no information about other two researchers (males, I assume, or perhaps females who had less-interesting biographies?). It was the same with the Physics Nobel except that I already knew there was a black hole at the center of the galaxy, and that those who found it are long dead. Instead the Note Prize was being awarded for a photograph of the black hole. Interesting (sure doesn’t look like a black hole to me). Is there something they learn from the photo. I’ve noted that we are likely within a black hole, and I show why this is using some, not too difficult math.

Having griped along this way, I have to say that that IFL isn’t that bad, it’s just non-mathy, popular, and a little grown up. That’s sad, but it’s not toxic. Grownups make money, and please customers, and that’s how it goes. To quote a wonderful book, The outsiders, “Nothing gold can stay.” In my own blog, I try to be more math-y, and more science-y. My model is Isaac Asimov, a writer who excited me to love science from when I was 8 to when I entered college, nine years later (1972). He would die of AIDS from a transfusion, 20 years after that.

Robert Buxbaum, February 28, 2021