Monthly Archives: January 2009

Year of the Ox, 2009

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According to high placed sources, 2009 is the Chinese year of the Ox. Hmmm.  If you wanted to buy an Ox, where would you go? What does one look for in an ox? If an excellent ox was standing next to a bad ox, how would you know?  Besides having tails suitable for stew, what else is tasty about the ox? Oxburgers?

An ox is a compact beast of burden- a sort of bulldozer on the hoof. Why didn’t Budweiser choose oxen to pull their famed lager wagon? If oxen were good enough for the Mormon trail and Paul Bunyan, why not for beer distribution? I’m gonna go have a beer and think about it.

Redoubt’s Rumbling Redux

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The Redoubt volcano along the Cook inlet in Alaska is showing seismic activity according to the Alaska Volcanic Observatory (AVO). Seismic activity may be a precursor to eruption. Dedicated seismic recorders show frequent bursts of activity on the volcano.  The USGS has a website with advice and information aimed at helping people cope with an ashfall. 

In the past, the prevailing winds have carried the ashfall in an easterly direction over and past Anchorage. According to AVO, Redoubt is a stratovolcano located several hundred km west of Anchorage. It has reportedly erupted explosively six times since 1778, with the most recent being in 1989-90.

Note to Wal-Mart:  You may want to stock up the anchorage stores with extra brooms and shopvacs.

The House GOP. Hear Them Squeal!

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Poor GOP. The party of values, Tom DeLay, and Karl Rove. Now that they are the loyal opposition, they seem to have forgotten their time in the sun. Remember the good old days when Majority Leader Tom “The Exterminator” Delay ran roughshod over house Dems? The tide has turned and today they are whining vociferously about the lack of input into legislation.  Should they be surprised at like treatment? Actually, they are not getting like treatment. Boehner and party have been asked to participate in problem solving and, naturally, they have reverted to their rabid, atavistic reflex for eating the liver of any democrat within reach.

Reactivity and Risk. Gaussling’s 10th Epistle to the Bohemians.

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A chemical plant performing synthesis is a place where the materials in use are purposely selected for certain attributes of instability. Chemical stability refers to the tendancy of a substance to remain unchanged when exposed to some kind of stimulus. That stimulus may be exposure to heat energy, mechanical shock, or a more precise chemical attack on particular functional groups. Unstable substances have a low threshold to change. Stable substances require more stimulus to cause a change in composition.

Substances that are extremely stable are often not very useful in near-ambient temperature chemical synthesis, i.e., saturated hydrocarbons, metal sulfates, silica, etc.  The lack of lower temperature reactivity (say, up to 200 C) can be compensated for by application of high temperatures. Petroleum refineries take full advantage of high temperature reaction chemistry to alter the composition of otherwise stable hydrocarbons.

We choose stable substances for duty as solvents, diluents, carriers, etc., precisely because of their non-changeability or stability. “Inert” solvents allow chemists to bring molecules into solution for selective transformations. Of course, we all know that most solvents have some influence on the course of a transformation, the point is that we can transform solute materials without the fuss of altering the solvent too.

Chemical synthesis requires the manipulation of reactivity (and therefore stability) to perform useful transformations. Without well placed instability on a molecule, there cannot be efficient, directed synthesis. It is the job of the synthesis chemist to apply the knowledge of reactivity.

Because of the inherent instability of reactive and flammable materials, chemical plants must require that certain behaviors, procedures, and knowledge be set into a formal structure. Actions and conditions must give predictable consequences. This structure is comprised of a set of standard- operating procedures, equipment, test methods, and safety requirements.

It seems silly to go to the trouble of detailing the merits of running a safe plant, but it is worth pointing out the layers of requirements on an operating plant. 

  1. Preservation of life, health, and the environment
  2. Compliance with federal, state, and local regulations
  3. To provide for the uninterrupted flow of goods and services in the conduct of business
  4. To qualify for affordable business insurance
  5. To be a good neighbor and stable source of gainful employment for all concerned

A company in the business of manufacture is exposed to many kinds of liability. A chemical manufacturing plant is subject to modes of failure and liability that set it apart somewhat. 

One result of chemical manufacture that sets it apart from other forms of industry is the combination of unknown risk and dread fear. For communities in the vicinity of chemical operations, fear comes from the combination of the unknown as new risks, unknown effects, or delayed effects with the dreaded possibility of catastrophic or fatal consequences, inequitable consequences, involuntary effects, and high risk to future generations (see: Perilous Progress: Managing the Hazards of Technology, Edited by Kates, Hohenemser, and Kasperson, 1985, Westview Press, Boulder, Colorado, p 108. ISBN 0-8133-7025-6).

While the neighbors of a furniture factory may be annoyed by the presence of a nearby woodworking shop, it is unlikely that the neighbors will be stirred into existential dread by its presence. The hazards of a woodworking plant are easy to imagine and therefore, easier to rank into the grand list of life’s dangers.

Chemical and nuclear risk perception score at the extreme ranges of risk perception. Both domains involve an agent of potential harm that is poorly understood by most people. Ionizing radiation is inherently destructive to tissues, but the exact relationship between quality and dose to risk is fuzzy at low level exposure. And because it cannot be sensed directly, fear of it’s presence can induce disturbing excursions of imagination and dread.

Fear of chemicals is widespread in the industrialized world. The downside to chemical operations has been immortalized by numerous well known industrial calamities like Love Canal (Hooker Chemical), Bhopal, numerous dioxin fiascos, PCB’s, or occupational exposure to asbestos or chromium (VI). There are a great many chemical items of commerce that are unavoidably hazardous to health.

Because of the risks associated with toxicity or exposure to hazardous energy from machines, chemicals, radiation, heat, noise, gravity, sharp implements, etc., the many layers of government have established agencies and a regulatory structure to diminish risk exposure to workers specifically and citizens generally.

The purpose of the chemical industry is to produce goods and services for people who want or need the value of it’s output. Like the ad says- “We don’t make the surfboard, we make it better”. Well, making the surfboard better inevitably requires that certain kinds of hazards be unleashed and managed. The expectation that hazardous materials can be eliminated in manufacturing is a fantasy. The manipulation of instability is inherent to chemical transformation. Zeroing out hazards has to come from the demand side of the market.

Russia to Produce More Aircraft Carriers

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Russian President Dmitri Medvedev announced recently, while on board the carrier Admiral Kuznetsov, that they will begin an aggressive campaign for the production of aircraft carriers in the next two years. In 2007, Admiral of the Fleet Vladimir Masorin, announced that within 20 to 30 years, Russia would have two carrier strike groups consisting of three carriers each. Russian style carriers are smaller than US carriers and have more defensive capability, reportedly giving them more maneuverability.

But to construct and service a major fleet, Russia needs a major port facility like Sevastopol, in the Ukraine, with its craggy coastline. Unfortunately for Russia (or more ominously, for the Ukrainians), a lease agreement with the Ukraine will expire in 2017. Reports suggest that the Ukraine is not interested in renewing this lease.

On the technical side, building a metal warship brings many kinds of problems that makers of fiberglass yachts and canoes don’t have to contend with. Testing for magnetic silencing and degaussing is one of them.

Fissile Molten Salt Reactors

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Like it or not, the world is fitted with a web of nuclear power infrastructure. And, like it or not, we have inherited the chore of managing nuclear materials and industries from preceding generations. The question that begs to be answered is, how should we go forward with this legacy of nuclear power technology? Do we plod along maintaining  the status quo? Do we replace aging nuclear plants with non-nuclear facilities? Or, do we ramp up with more nuclear plants?

On the pro-nuclear side, alternative reactor schemes are surfacing.  Reactor designs that have been proposed for years are showing up on the internet and into the daylight.

One intriguing design utilizes a fissile molten salt that is circulated through a moderator assembly and cycled through a heat exchanger. In this scheme, the fuel is also a working heat transfer fluid. It is called a liquid fluoride reactor.  Many kinds of molten salt compositions are possible, but one is composed of (72 LiF, 16 BeF2, 12 ThF4, 0.3 UF4).  The designs I’ve seen use continuous fuel processing to keep an optimal fuel composition in use. The reactor described in the previous reference has a negative temperature coefficient, meaning that the fuel becomes less reactive as the temperature rises. This is an important safety attribute.

There is no point in a recital of the technical details here. The reader can follow the links if interested.

US Airways Splashdown on the Hudson

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The Hudson River touchdown of US Airways flight 1549 has been called a miracle by some folks. How these folks would describe the ingestion of a flock of birds in terms of miraculous phenomena has not been disclosed. Whatever it was, the aircrew certainly performed admirably.

If you look at a map of the flight path and note the timing, one minute after the birdstrike the A320 had descended from 4000′ to 2000′. At this phase of flight 1549, the airplane is heavy with fuel, baggage, and people. They are configured for climbout and are navigating in congested airspace at low altitude.  At least one of the pilots has his head on a swivel watching for traffic while the other is monitoring flight control systems.

After the birdstrike, there would be some seconds of confusion where the pilot and first officer would have to analyze the warning annunciators as well as what story the flight instruments are telling them. Loss of power on climbout means a prompt loss of airspeed. Here the pilot and first officer would coordinate their cockpit duties. One pilot will concentrate on flying the airplane while the other would, for instance, focus on an engine restart, declaring an emergency with the tower or TRACON, notify the cabin crew for emergency procedures, etc.

While the pilots are determining what kinds of flight controls they have to work with and what other failures may be unfolding, they have to establish a standard airspeed that will minimize their decent rate. This gives them more time in the air and correspondingly, more landing options.

An airplane does a coordinated turn by banking the wing and tilting the lift vector in the direction of the turn. As you tilt the wing, the force vector acting against gravity becomes smaller and without coordinated input from other controls and a bit of power, the airplane will begin to sink.

The point is that when you bank an aircraft during a deadstick glide, you will increase the sink rate. Looking at the map, the pilot could not afford to lose anymore altitude by attempting to make a gliding turn to Teterboro to get lined up with the runways. They had no choice but to continue straight forward along the direction of the river and hope they could land in the water without dipping a wing and cartwheeling the airplane.

I’d say the aircrew made a series of good decisions.