what can the matter be | Chemical & Engineering News
Volume 82 Issue 20 | p. 5 | Letters
Issue Date: May 17, 2004

what can the matter be

Department: Letters
MECHANOSYNTHETIC REACTIONS
As conceived by Drexler, to deposit carbon, a device moves a vinylidene-carbene along a barrier-free path to insert into the strained alkene, twists 90º to break a p bond, and then pulls to cleave the remaining s bond.
Credit: COURTESY K. ERIC DREXLER
8220lett1a
 
MECHANOSYNTHETIC REACTIONS
As conceived by Drexler, to deposit carbon, a device moves a vinylidene-carbene along a barrier-free path to insert into the strained alkene, twists 90º to break a p bond, and then pulls to cleave the remaining s bond.
Credit: COURTESY K. ERIC DREXLER

Oh dear, what can the matter be?

Some pictures are more revealing than the authors of their captions intended. Your article on the Smalley-Drexler nanotechnology debate includes one such picture, reprinted here (C&EN, Dec. 1, 2003, page 37).

The picture depicts the extrusion of a single molecule and the deposition of a single atom--but while the vinylidenecarbene moiety is shown one atom at a time, it emerges from a featureless gray tube. Clearly, the field of view this cylindrical object subtends is at most 10 atoms wide and a few thick, yet it is depicted with a perfectly smooth contour, and not as a polygonal atomic or molecular structure. Since not even metallic glass is amorphous on the scale illustrated, can you tell us what kind of matter it is supposed to be made of, and how we are to imagine it applying torque enough to shear a pi bond while allowing a reactive and strained molecule to slip through?

Do let us know soon--I'm sure we'd all like to order some from Acme Products before stock runs out.

Russell Seitz
Cambridge, Mass.

 

AIChE's alliance thoughts

As President of the American Institute of Chemical Engineers (AIChE), I read with interest the article "Council Discusses Partnering with AIChE" (C&EN, April 26, page 43). I attended the council meeting in Anaheim and was very pleased with the generally positive response from ACS leaders as reported in the article.

I would like to assure the readers of C&EN that AIChE has actively communicated with our members about the progress of discussions with ACS. In addition to communications previously sent to every AIChE member, we recently held an open forum at our meeting in New Orleans on April 25, in which ACS Board Chair James D. Burke participated. The forum was well attended, including four past AIChE presidents, at least one person who was a 50-year member of both<br > societies, and a spectrum of other AIChE and ACS members. The comments and questions from the floor reflected a broad base of support for continuing our partnering discussions.

Furthermore, we would like C&EN readers to be aware that AIChE has substantially stabilized its financial position since last reported in C&EN. AIChE is well positioned to maintain its own viability and seeks to develop a mutual opportunity to create value for ACS and AIChE members through collaborative activities between our societies. I look forward to continuing our discussions.

Bill Byers
Corvallis, Ore.

 

No confidence in No-D

In the article titled "Proton NMR Without Deuterated Solvents," Thomas R. Hoye mentioned briefly that one of the reasons for a deuterium solvent is to lock onto the magnetic field so that slight drifting does not cause artifactual signals in the spectrum (C&EN, March 22, page 38).

The deuterium-free technique works fine for routine 16­256 scan 1H nuclear magnetic resonance (assuming short relaxation times), but oftentimes it is also necessary to run a 13C NMR of the sample. A decent-looking 13C NMR takes much longer to acquire than a routine 1H for a variety of different reasons. This difference in time is sometimes long enough to cause artifactual peaks due to magnetic field drift to become apparent in the absence of a suitable deuterated solvent. And one can totally dismiss the idea of a 2-D NMR liquid experiment (especially a through-space interaction) without a deuterated solvent. The magnetic field drift in even the best of superconductive magnets would be enough to render the data useless.

I feel that it is necessary to point out that, although possible to conduct liquid NMR experiments without a deuterated solvent, there are severe limitations that seem to have been overlooked by the authors. Even though there appears to be one simple single-pulse experiment that will work without a deuterated solvent, there are many others that will not.

As for shimming in the absence of a deuterated solvent, or shimming on the FID (free induction decay), as it is commonly referred to, dilute samples will pose a great problem because the integral of the FID won't become apparent after one scan. There may be a need to wait for hundreds of scans to add until one can see which shimming direction is needed. And as for shimming being like riding a bike, I suppose that's a good analogy if your bike has as many controls as a 747, and 22 or more shimming gradients to boot.

Bernie O'Hare
State College, Pa.

 

Proper names

It is with disappointment that I continue to see such terms as mustard "gas" and nerve "gas" used in C&EN. While those terms are frequently used in the popular press, chemists and chemical engineers should know better. Mustard agent, depending on how well it has been purified, has a normal boiling point of about 217 °C; GB (sarin) boils at 158 °C; and VX boils at 298 °C. Therefore, none of these can be considered a gas at ambient conditions, though they will slowly vaporize.

These agents are weaponized by being packaged with an explosive to atomize the agent when the target is reached. In fact, the reason the 1995 Aum Shinrikyo sarin attack in the Tokyo subway killed 12 people instead of hundreds is because of the failure of the primary mechanism they intended to use to disperse the liquid agent.

Stanley I. Sandler
Newark, Del.

 

A rose by any other name ...

I enjoyed your article "Harnessing Nanotechnology" (C&EN, April 19, page 30). "Nanotechnology [that] refers implicitly to a set of capabilities at the atomic scale" truly has possibilities that are awe inspiring.

We have recently prepared a nanomaterial in our laboratory that is less than 1 nm across but is capable of sensing the pH of an aqueous solution. In the presence of sufficient base, it absorbs light at 550 nm, thus emitting a visible light signal. We plan to call this nanomaterial "phenolphthalein," subject to a patent search to see if the name is not already in use. You also report on "water- and stain-resistant textiles," and we have another project where we are nearing success on a water-repellent nanomaterial that is a triester of glycerol.

The only impediment to this new field may lie in its name. The word nanotechnology carries an implication of smallness that may drive away big investors. May I suggest a different name I found in the old literature; that is, chemistry.

Paul Haberfield
Brooklyn, N.Y.

 

Write and wrong

I read the article "Ethics 101" and was pleased to see the increasing interest in the human interactions part of our profession (C&EN, April 26, page 33). In researching for an upcoming book on career development for chemists, I found that one area within ethics was very high in people's minds.

The issues of credit and plagiarism touch many researchers deeply. The sharing of ideas and unpublished results is an integral part of the networking that goes on all over our profession. The use of someone else's ideas without acknowledgment or a thought of a possible credit as a coauthor can leave deep scars that stifle future collaborations. The most blatant, tangible form is using someone's already published work or writing without credit.

This is high on people's lists as unacceptable and unethical behavior because it is so personal, a stealing of one's ideas. This can be taught and learned, contrary to the viewpoint described by Brian P. Coppolla that falsifying results from an ingrained personality that is set by adulthood. Sharing or not sharing appropriate credit is not as deeply seated as a value of good versus bad. But we all desire to be recognized for our contributions, so there is an empathy within us to want to do that as well when we deal with others.

John C. Fetzer
Pinole, Calif.

Unfortunately, a course in ethics 101 comes too late both for chemistry majors and other students at the college level. The specifics of what represents a breach of ethical conduct should have been obvious to the student based on logic and background. Certainly, any individual brought up with an appreciation and devotion to ethical behavior would know that all previous workers in the field should be acknowledged, that their work should not be plagiarized, and that data should not be fudged nor eliminated to agree with a preconceived notion or possible result.

If the student is unaware of these facts, then he should not be in chemistry or college. Perhaps this judgment appears harsh, but certainly the integrity of scholarly work is threatened by anything less than strict adherence to ethical principles.

Nelson Marans
Silver Spring, Md.

 
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