I get to enjoy a commute through farm country every work day. It is my habit to pull over and watch the crop dusters when they’re out. I’m secretly jealous of them as they zoom  with their wheels just above the crop in a powerful turboprop aircraft. In the fall of 2017 I caught this fellow spraying what I estimate is an antifungal onto a corn crop near the end of the growing season. The negative image seemed more interesting than the positive.

 

Duster in Negative Space

Helicopters show up now and again. These folks can do a 180 turn at the end of a pass faster and in a tighter space than can a fixed wing aircraft. Also they can pause to think about things whereas a fixed wing aircraft cannot.

 

Crop Dusting Chopper

Think what you will about spraying. If they’re out there, I’m going out to watch, but not so close as to smell the spray.

 

 

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As I look back on the chemistry coursework I took as an undergrad, a few classes stand out as especially useful over my career. First some qualifications: I became an organic chemist because I found it to be a good “fit” for my brain. So, organically oriented courses were obviously useful. The chemistry department at my alma mater followed guidelines for the ACS Certified curriculum. Thus required coursework was prescribed and completed.

Chemistry coursework of enduring value.

Sophomore Organic Chemistry:  Fortuitously, I took 2/3 of my general chemistry in the preceding summer, so I was able to take organic chemistry in my freshman fall term. This was the great awakening. It was crystal clear that this was what I was meant to do. The benefits from a course on organic chemistry are many. Foremost on the list is that it is structurally and mechanistically oriented. The cognitive benefit is that a structural and mechanistic approach can render the subject a bit less abstract. At least to highly visual people like myself.

Molecules are tiny objects with even tinier places on them where certain things can happen. Reaction chemistry is revealed as a graphic sequence of specific events on specific objects. This allows the mind to put together patterns of functional groups and reaction motifs. In my view, a year of organic chemistry is the reward for slogging through a year of general chemistry. Gen Chem doesn’t make you a chemist. A tech perhaps. But gen chem is to the chemistry curriculum as The Hobbit is to The Lord of the Rings- a necessary prelude. That is what I used to tell students, anyway.

Qualitative Analysis: This was the third quarter of a 3-quarter sequence of freshman chemistry. It was heavily lab oriented with a focus on the separation and identification of inorganic cations and anions. It was substantially descriptive chemistry where clever schemes were used to isolate ionic species.

Analytical Chemistry: This is where you really begin to feel like a chemist. We all learn skills in this class that last. It is measurement science and error analysis. Every chemical scientist should have a solid foundation in wet chemistry.

Instrumental Analysis: This class was taken after Analytical Chemistry and built upon learnings from it. I’d offer that time spent on learning how your detectors work and their limitations is invaluable.

Organic Qualitative Analysis: I’ve come to learn that this class was an unusual experience. We learned to identify organic substances using fundamental means for 1982. Melting points, melting points of derivatives, NMR (60 MHz!!) & IR spectra, solubility, sodium fusion, Lucas Test, 2,4-DNP-hydrazones etc. We were required to get three data points per unknown to conclude that we had identified the substance. An indispensable resource was a compendium of derivative properties. A challenging but good experience.

Undergraduate Research: Two years of this experience was invaluable as a prelude to grad school. The asymmetric reduction of ketones (1982-84) work here lead to my doing a doctorate in asymmetric C-C bond forming chemistry and a postdoc in catalyzed C-H insertion chemistry. This activity is a must for those who want to pursue post-graduate work.

Advanced Organic Chemistry: What can I say?

Advanced Inorganic Lab: Good experience. Did some glass blowing. Worked on a vac line, tube furnace, and in a glove box. Good intro to airless work which would be important in grad school.

Chemistry coursework that was inadequate.

Inorganic Chemistry: I took this class in a time when symmetry and spectroscopy topics were an emphasis in the textbooks. Maybe it is still like that. But I wish we could’ve spent more time on descriptive and preparative inorganic chemistry.

Physical Chemistry: At the time it seemed as though the mathematical manipulations were more important than what the relationships actually meant. Statistical mechanics was played down in favor of more time on quantum mechanics. On entrance to grad school of the 5 qualifier exams taken, stat mech was the only one I failed.

Coursework outside of chemistry that has been of enduring value.

Microbiology: My only college bio class. I swear that this class has saved me from food self-poisoning more than I realize. That is a lifelong benefit, but so was the insight into a fascinating world. The course included an intro to immunology which also has been useful.

Communications: I made great strides in learning how to do public speaking.

Russian Language:  Took only 1 year- just enough to be dangerous. It was of nearly zero help when I eventually visited Russia years later on a business trip.  I was interested in the history and politics of Soviet Russia in that slice of time during the cold war.

Computer Programming: Should have taken more classes. In the early eighties we had to use either punch cards or the DEC terminal. Oh, I hear that FORTRAN still sucks.

Air Force ROTC: The biggest benefit was that I learned I am not military material in any sense. But, the communication skills and the history of air power were useful. I couldn’t march to save my life. I was Gomer Pyle.

 

 

One of my work duties is to give safety training on the principles of electrostatic safety: ESD training we call it. The group of people who go through my training are new employees. These folks come from all walks of life with education ranging from high school/GED to BS chemists & engineers to PhD chemists. In order to be compliant with OSHA and with what we understand to be best practices, we give personnel who will be working with chemicals extensive training in all of the customary environmental, health and safety areas.

I have instructed perhaps 80 to 100 people in the last 6 years. At the beginning of each session I query the group for their backgrounds and ask if it includes any electricity or electronics study or hobbies. With the exception of two electricians in the group, this survey has turned up a resounding zero positive responses.

Admittedly, there could be some selection bias here. It could be that people with electrical knowledge generally do not end up in the chemical industry. My informal observations support this. But I’m not referring to experts in the electrical field. I refer to people who recall having ever heard of Ohm’s law. One might have guessed that the science requirements for high school graduation may have included rudimentary electrical concepts. One might have further suspected that hobby electronics could have occupied the earlier years of a few attendees. Evidently not. And it does not appear that parents have been very influential in this matter either.

I’m struggling to be circumspect rather than righteous. It is not necessary for any given individual to have learned any particular field of study. It is not even necessary for most people to have studied electricity. But it is important for a core of individuals to have done so. So, where are they? And why aren’t more people curious enough to strike out on their own in the acquisition of electrical knowledge?

Back to electrostatics. In order to have a working grasp of electrostatic principles, the concept of the Coulomb has to be conveyed. Why the Coulomb? Because it is the missing piece that renders electrostatic concepts as mechanistic. It is my contention that a mechanistic grasp of anything can help a person to reason their way through a question. The alternative is rote memorization. The mechanistic approach is what drives learning in the natural sciences.

To be safe but still effective as an employee, a person needs to be able to discriminate what will and what will not generate and hold static charge to at least some degree in a novel circumstance. By that I mean how accumulated or stranded charge can form and what kind of materials can be effectively grounded. If you are working with bulk flammables, your reflexes need to be primed continuously to recognize a faulty ground path in the equipment around you. At the point of operation, somebody’s head has to be on a swivel looking for off-normal conditions.

It is possible to cause people to freeze in fear and over-react to unseen hazards like static electricity. But mindless spooking is a disservice to everyone. To work around flammable materials safely requires that a person understand and respect the operating boundaries of flammable material handling. Those boundaries are grounding and bonding (see NFPA 77), avoiding all ignition sources, good housekeeping, and maintaining an inert atmosphere over the flammable material.

Much of electrostatic safety in practice rests on awareness of the fire triangle and how to avoid constructing it.

Back to electrical education. There are numerous elements of a basic understanding of electricity that will aid in a person’s life, including safely working around flammable materials. One element is the concept of conduction and what kinds of materials conduct electric current. Another is the concept of a circuit and continuity. Voltage and its relationship to current follows from the previous concepts.

I would offer that the ability to operate software or computers is secondary to basic knowledge of how things work.

Connecting these ideas to electrostatics are the Coulomb and the Joule. One volt of potential will add one Joule of energy to one Coulomb of charges. One Ampere of current is one Coulomb of charges passing a point over one second. Finally, one Ohm is that resistance which will allow one Ampere of charge to move by the application of one volt.

For a given substance- dust or vapor- a minimum amount of energy (Joules) must be rapidly released in order to cause an ignition. This is referred to as MIE, Minimum Ignition Energy, and is commonly measured in milliJoules, mJ.

A discussion on sparking leads naturally into the concept of power as the rate of energy transfer in Watts (Joules per second), connecting to both the Joule and Ohm’s Law. Rapid energy transfer is better able to be incendive owing to the finite time needed for energy to disperse. Slow energy transfer may not be incendive simply because the energy needed to initiate and sustain combustion promptly disperses into the surroundings.

A discussion of energy and power is useful for a side discussion on how the electric company charges for energy in units of kilowatt hours (kWh). This is a connection of physics to money.

The overall point is that a rudimentary knowledge of electrical phenomena is of general use, even in the world of chemical manufacturing. I often hear people talk about the importance of “tech” in regard to K-12 education. By that they seem to say that using software is the critical skill.  I would offer that the ability to operate software or computers is secondary to basic knowledge of how things work. Anyone with a well rounded education should be able to learn to use software as they need it.

Interesting. I know two chemists and an engineer from my miniscule spheroid who have recently joined the marijuana extraction industry here in Colorado. Crimony, it makes me wonder what my problem is. Alright, it turns out that’s easy to explain. I really dig reaction chemistry and thermo, you know, real sciency stuff. Not much of that in the retail or wholesale extractives business. I have this suspicion that it will soon – if not already – be corporatized, IPO’d, and raced full throttle by scheming finance MBA’s like every other growth business. They can have it. Capitalism is like a stomach- it has no brain. All it can do is endlessly demand more.

After another tedious weekly teleconference our group adjourned and stood up from the table in the conference room.  I was furthest from the door but my normally rapid pace put me in the lead to exit. All at once mid-stride, just as my rearward foot began to move forward, it caught a phone cord that became taut instantly. Consider that a walking stride is a series of balance/off-balance conditions where the walker is constantly catching his/her balance. I had been caught off-balance at the wrong moment in my step.

My recollection of that falling moment brings to mind the droll voice of the bowl of petunias in The Hitchhiker’s Guide to the Galaxy.  Resigned to its fate, its final lament is “Oh no, not again.” I can relate.

Mid-fall my lips came within a hairs breadth of landing face first on an armrest. Luckily I hadn’t shaved that day so I actually had that hairs breadth.  On impact with the carpeted floor my first emotion was one of anger. I had successfully negotiated the cords for nigh on eleven years. But this day it was not to be. This day I would tip like a sack of dirt in front of a room full of colleagues.

After a moment on the floor I spouted an incredulous “Mother F**ker!! followed by an equally enthused “Son of a B*tch!!” Truth be told, it was an utterly sincere cleansing of my dismay. My screens were down and the profanities leapt into the ether. After a few awkward moments I got up and repaired to the solitary confines of my office.

Later I jokingly apologized for my “gravitationally-induced Tourette’s.” I gathered that the unexpected outburst had provided a welcome bit of mirth after a highly technical meeting.

 

In the course of my forays into chemical sourcing or searching for data, I have begun to notice something about product entries in the online Sigma-Aldrich catalog. I’m finding that since the acquisition of Sigma Aldrich by Merck KGaA, MilliporeSigma as it is now known, many of the compounds that I find listed say the product has been discontinued. Is it just fortuitous, or is it not? Is the catalog collection being trimmed?

Have I been collecting data? Pffft! Of course not, silly. It’s just the subjective experience of having found few if any Aldrich catalog entries labeled as discontinued over the past few decades. Recently I’m landing on the pages of discontinued products. Hmmm.

Over the many years, buying reagents from Aldrich has saved countless chemist-days in lab productivity. In fact, the availability of their huge collection of chemicals has driven the direction of much research out there based simply on the availability of reagents for purchase.

I blame the MBA’s. This has the smell of overly smart weasels marketing people.

A recent paper (free) in Geophysical Research Letters reports the discovery of long anticipated ionospheric disturbances caused by the passing of the moon’s shadow over the earth during an eclipse. The paper, submitted by the MIT’s Haystack Observatory, reports the occurrence of ionospheric bow waves associated with the shadow ground-track of the August, 2017, North American eclipse.  The online source, MIT News, summarized the discovery.

 

I’ve been using a Mettler-Toledo (MT) RC1e reaction calorimeter for about 6 years. Our system came with MT’s iControl software, RTCal, and 2 feed pumps with balances. Overall it has proven its worth for chemical process safety and has helped us understand and adjust the thermal profile of diverse reactions. Like everything else, MT’s RC1e has many strengths and a few weaknesses.

The RC1e’s mechanical side seems reasonably robust. Our instrument sits in a walk-in fume hood resting on a low lab benchtop supported by an excess of cinder blocks- it is a heavy beast. During installation we discovered that the unit would not achieve stable calibration with the hood sash down. The control box mounted on the instrument didn’t work properly on installation. After a trip to the repair shop, the box was returned as functional but without finding the fault.

Recently we had a mixing valve fail in the heat transfer plumbing, resulting in down time. Diagnosis of this was unsuccessful over the email and phone, necessitating a service call. Parts may not be inventoried in the US and consequently must come from Switzerland. Expect Swiss prices and less than snappy delivery. Hey, it’s been my experience.

A chiller unit is required for RC1 operation and can add 15-30k$ to the setup cost. Users will have to contend with the loss of floor/hood space in the lab for the chiller and RC1. Chillers can take many hours to get down to the set temperature. Given that RC1 experiments can also be lengthy, plan accordingly. Our (brand new Neslab 80) chiller requires nearly 2 and 1/2 hours to get from +20 C to -20 C, which is the upper chiller temperature we use, depending on the reaction chemistry. For reactions that are on the sporty side, we’ll drop the chiller to – 50 C.  This is near the  minimum temperature for the water-based chilling fluid we use. Early on I opted for an aqueous lithium formate solution with a very low freezing point. It’s a little spendy, but a pool of it on the floor cannot warm up to become combustible and an ESD ignition hazard. Also, it is odorless.

The chiller required the wiring-in of a dedicated single-phase 240 VAC circuit. With the chiller using single-phase and the RC1e using 3-phase 240 VAC, it is important to assure that one cannot inadvertently connect into the wrong power circuit (idiot proofing). The chiller plug design should already prevent this. It is critical that the electrician is alert to this and does NOT jury-rig the plugs to use the same style of connectors because he has only one style in the parts bin.

Some comments on the collection and interpretation of RC1 thermograms.

  • It is critical that those who request RC1 experiments understand the limitations of the instrument. For instance, we use a 2 Liter reaction vessel with a 400 mL minimum fill volume. Refluxing is not allowed owing to the huge thermal noise input from the reflux return stream. Special equipment is said to be available for reflux.
  • Experiments must be carefully designed to elicit results that can answer questions about feed rates and energy accumulation.
  • Like many instruments, the RC1 needs a dedicated keeper and contact person for inside and outside communication. A maintenance logbook should be kept next to the instrument if for no other reason than to pass along learnings from previous issues.
  • If thermokinetic measurement is part of your organization’s development SOP, someone on staff should be reasonably familiar with chemical thermodynamics. That can be a chemical engineer, as may often be the case.
  • The users of thermal data are likely to need help with interpretation of the results. Be prepared to offer advice on interpreting the data, taking care not to over-interpret. If you don’t know, say so. It is easier to claw back “I don’t know” than “yeah, go ahead and do that …”.
  • Do not be anxious to singlehandedly bear the weight of responsibility for safety. Safety is a group responsibility.
  • Be curious. How do the insights and learnings from the data translate into best practices? What changes, if any, can the process chemists make to nudge the process for better safety and yields? A credible specialist in RC can make comments or ask questions that lead to better discussions on thermal hazards. Be a fly in the ointment.
  • Never forget that a reaction calorimeter is a blunt instrument for the understanding of a reaction. An RC1 thermogram is a composite of overlapping solution-phase phenomena. Interpretation of results can be greatly refined by pulling timely aliquots for NMR, GC/MS, or HPLC analysis.
  • A database should be constructed to collect and immortalize learnings from all safety work and RC1 learnings fall into that group.

There is the question of who collects and presents the data. An engineer or a chemist? Engineering thermodynamics is a big part of a chemical engineer’s education and skill set. As a plus, an engineer can take thermal data and apply it to scale-up design for safety and sizing of equipment and utilities. You know, the engineering part.

Do not be anxious to singlehandedly bear the weight of responsibility for safety. Alpha males- are you listening??  Safety is a group responsibility that should originate from a healthy group dynamic.

There’s a good argument for a chemist to conduct RC experiments as well. A trained synthesis chemist is qualified to conduct chemical reactions within their organization. That includes sourcing raw materials, handling them, running the reaction, and safely cleaning up the equipment afterwards. But interpreting RC1 data has a large physical chemistry component. In my experience, run of the mill inorganic/organic synthesis people may have seen PChem as an obstacle rather than a focus in their college education. Their skill set is in instrumental analysis like NMR and chromatography, mechanisms, and reaction chemistry. I would recommend having a PhD chemist with a focus on thermo in a leadership role when calorimetry is a key part of a busy process safety environment.

Safety data can be collected and archived all day long. The crucial and often tricky part is how to develop best practices from the data. I would offer that this is inherently a cross-disciplinary problem. Calorimetric data from reaction chemistry can be collected readily, especially with the diverse and excellent instrumentation available today. Adiabatic temperature rise, ΔTad, can be determined by a chemist, but it’s the engineers who understand how the equipment may respond to a given heat release. A smooth and efficient technology transfer from lab to plant happens when good communication skills are used. Yes, SOP’s must be in place for consistency and safety. But the positive effect of individuals who have good social skills and are prone to volunteering information cannot be underestimated.

 

An automated Windows update disrupted my life today. It swooped in overnight like a winged wraith, did its dark deeds, and flapped quietly back to the dank hole from whence it came. My RC1 data may yet reside unscrambled on the disk drive, but it lies orphaned from the mother iControl application which mockingly professes no recollection of 18 hours of sweet data lovingly produced. The curs in IT can only “tsk, tsk” in their antiseptic way while bobbing pointed heads in faux dismay. Another first-world difficulty uncovered for all to see.

The electronic news world is a colossal hodgepodge of media jumping on anything new and “compelling”. The weekend’s compelling news du jour is Ret. Adm. Mike Mullen‘s comments on the likelihood of nuclear war with North Korea (DPRK). As a retired admiral and chairman of the Joint Chiefs, Mullen is a strategic thinker. These days he is very pessimistic of the US finding a peaceful way forward with the DPRK.

Taken alone, this view could be ignored as an outlier. But against a backdrop of other seemingly credible reports, Mullen’s worry could be taken as another indicator of the tempo of concern within much of DC. Consistent with Mullen’s worry is a lengthy 12/14/17 interview with Senator Lindsey Graham written by Uri Friedman at The Atlantic. Graham is an opinion leader on the matter of the DPRK. The article is well written and I must highly recommend it.

The frothy part of this DPRK boil-up is talk of nuclear conflict. The language that I have heard does not distinguish the various scenarios of how a nuclear war would unfold on the Korean Peninsula. One thing that was made clear by Graham in the Atlantic article is that there could be no limited strike on the DPRK. I assume it means defensively or otherwise. Any attack on the North, nuclear or conventional, would have to result in the complete collapse of the Kim regime.

The US military develops and refines war plans in preparation for any contingency. But, I’m curious how the psychological impact of the use of nuclear weapons will play in the various war cabinets of the world. After all, the nuclear-bomb genie has been kept in the bottle since August, 1945. Will a first use on or by the DPRK lower the threshold for other nuclear states?

A nuclear weapon married to a missile is a highly engineered machine that is at the apex of multiple military technologies. Expertise and a minimum of infrastructure in metallurgy, nuclear physics, chemistry, propellants, and delivery vehicle technology is necessary for accurate execution of a strike. For the DPRK to maximize the punch of its limited nuclear armaments, a strike relying on accurate delivery of a nuclear war shot to a remote or hardened target would require their leadership to gamble on layers of unproven or unrefined technology. The Kim regime may be a political malignancy, but they are not stupid.

Suppose the DPRK is able to strike some important targets with its nukes. Surely some in the North’s command know the consequences to follow. Decapitation of its leadership and annihilation of its war making capacity are a certainty.

For the US, the use of a nuclear war shot on the DPRK is not an inevitable result of physics like the apple that fell on Newton’s head. A release from the US nuclear arsenal is a choice and thus psychological in both application and long term consequence. Would a US nuclear response to a nuclear strike- anywhere-  by the DPRK make sense for the US in the subsequent post-war world?

The last big war, WWII, started conventional and ended nuclear.  Since then, the threat of mutual nuclear conflagration has helped to keep the peace by serving as a deterrence. Mutual Assured Destruction, MAD, is credited, superficially a least, with keeping armed conflict a strictly chemical explosives activity. What happens to the ground under the psychological pedestal supporting MAD when a nation-state uses nuclear weapons thinking it could win a conflict? How would the various national policies on first use change across the world and what do the likely outcomes look like?

There are many issues that follow from conflict with the DPRK. I hope that as much energy is given to the diplomatic scene as the theatre of war.

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