Laser devices aid fast-chemistry studies - C&EN Global Enterprise

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ingly endless series of solar rallies. Utilities will hold open houses to show off their solar research. In Austin, Tex., groups will race to build the most efficient greenhouse in the shortest time, with the winner to be included in the Guinness Book of Records. The race will be timed with a sundial. DOE will host its own "Sun Dial" in 10 major cities: DOE solar experts will man telephones to give advice on solar energy applications. The American Chemical Society will celebrate Sun Day at its Washington, D.C., headquarters with a solar cookout (using a solar cooker) and a display of solar equipment and information. Sun Day's planners emphasize that they do not want the event to become an antinuclear rally. Yet many in the nuclear industry are worried that Sun Day will, in the words of one industry observer, "be perverted by the most rabid antinuclear elements." The Society for the Advancement

of Fission Energy (SAFE), in Monroeville, Pa., is urging its members to counter with their own advertisements, information booths, and bumper stickers—all on the theme that nuclear and solar power are ideal partners. SAFE may have trouble selling that message to Sun Day participants, since in some cases the local Sun Day coordinator also is the local antinuclear activist. Although Solar Action Inc. will cease to exist as a legal entity after Sun Day, Hayes believes that there will be some "strings of continuity" between that organization and a national solar lobby group that he hopes to have functioning by early summer. He also hopes that the local Sun Day organizations, which exist now in most major cities, will remain as active lobbies at state level. D

Handler urges support for young scientists A lost generation of young scientists is a bleak prospect. Last week, a call for measures to counteract this potential problem came from Dr. Philip Handler, president of the National Academy of Sciences. As is the practice of the academy's president, Handler surveyed the state of U.S. science in his report to the membership at the academy's annual meeting in Washington, D.C. Scientifically, he found the past year to have been "marked by sterling accomplishment." But he also noted some disturbing developments. Symptomatic of one of them is the seeming discrepancy between a return of federal support of research to the previous high of 1967 and plaints from the scientific disciplines that available funds are "woefully insufficient" to support the scientific enterprise. From 1967 to 1977, Handler points out, the total community of employed Ph.D. scientists virtually doubled, from 135,000 to 267,000. The number of Ph.D.'s in the physical sciences grew 5.9% per year, in the social sciences 8.3% per year, and in the life sciences 9.5% per year. Although not all are engaged in research, the fraction of those who wish to probably has remained constant. Meanwhile, Handler notes, the work of science each year grows more sophisticated, requiring more elaborate equipment and more trained hands. If the value of this factor is merely 3.5% per year, Handler says, then the growth of the scientific community combined with increased sophistication would have required an increase in funding of 10% per year in constant dollars if the research community were to be maintained at the same level of relative effectiveness as it was in 1967. Funds available now are perhaps a third of this. Thus, the coming demographic decrease in the flow of young people into science may appear fortuitous—providing some of the brightest ones continue to opt for scientific careers. But, says Handler, that demographic decline already has been discounted by those responsible for universities' staffing patterns. "The opportunities of young scientists for tenure track positions are being severely restricted and young people know it," Handler says. "Hence, we could stand in danger of losing much of an entire generation of young scientists—a loss that should be simply unacceptable to the nation." To counteract this possibility, he

says, it is imperative that federal science-supporting agencies clearly recognize these circumstances and prepare to fund much larger numbers of postdoctoral fellows than ever before, and with longer tenure than in the past. Such positions would be designed for individuals more or less at the assistant professor level with the positions made definite for at least five years and renewable once. Such programs could provide opportunity for young and mid-career scientists while the present cohort of tenured faculty moves through time. "This will not be inexpensive," Handler says, "but it may prove absolutely essential." •

Laser devices aid fast-chemistry studies Fast chemistry is changing fast, Sir George Porter noted in a lecture at the National Academy of Sciences in Washington, D.C, last week. Porter outlined how laser spectroscopy is developing rapidly, producing hybrid instruments with improved capabilities. Significantly, the newest instruments permit scanning at lower input energies than before. That, says Porter, is an advantage in studying sensitive biological tissues, such as those conducting photosynthesis, that can yield misleading information if blasted with too much light energyLasers play the kingpin function in the fast-probe instruments. "The most powerful at the moment," says Porter, was developed at Bell Telephone Laboratories. It employs two lasers—one an excited-dye type and the other mode-locked. This instrument can deliver a weaker and hence less-disturbing excitation signal to the sample being studied. Though the signal coming out also is weaker, the instrument scans repeatedly to provide better data. An improved hybrid instrument is in the works. It will combine the advantages of repeat scanning used in the double-laser system with those of a device using a streak camera. In that, a laser drives electrons off a photocathode at rapid speeds to give one-picosecond pulses. Such instruments deliver a lower excitation signal to samples, a factor that already is proving important, Porter says. For instance, his group is studying the early events after light strikes chlorophyll molecules in a chloroplast, the seat of photosynthesis. Chlorophyll plays two roles: Most of the molecules simply catch the incoming photons of light, eventually May 1, 1978 C&EN

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delivering them as energy to the minority of chlorophyll molecules that perform photochemistry—that is, donate electrons to activate the biochemical machinery involved in photosynthesis. So far, Porter finds that the weaker laser pulse gives information that is more consistent with what others find using different methods. Thus, the light-catching chlorophylls remain excited for about 500 picoseconds after a pulse before delivering energy. However, if they can't deliver that energy because the secondary chlorophylls are shut down, they remain excited for about three times longer. Before the new lasers were available, Porter's group and others saw much lower values, probably because the intense pulses produced more than one excitation per unit. Such multiple events tend to annihilate one another. "These first steps in photosynthesis have been the 'dark' areas," Porter points out. "But they will be brought to light within the next five to 10 years." D

Bell Labs instruments have biomedical uses Biomedical research is not the area for which Bell Telephone Laboratories is best known. But it was the biomedical applications of two new instruments developed there that were drawing attention last week. These applications seem, for the moment, to be at least as important as the communications applications that triggered the development of these instruments in the first place. The first technique, called electron energy-loss spectroscopy, can pin-

point and identify individual atoms of low-atomic-weight elements in solids. Developed by Bell Labs scientists David C. Joy and Dennis M. Maher, the technique can be used to locate carbon atom impurities in silicon integrated circuits. Working in conjunction with Dr. Jonathan L. Costa and others at the National Institute of Mental Health, Dr. Joy and Dr. Maher have used the technique to locate exactly where the neurotransmitter, serotonin, is stored in blood platelets. The researchers find that lithium is stored in the same part of the platelet. This finding may be of significance in unraveling lithium's role in controlling mental depression. Electron energy-loss spectroscopy is a form of electron microscopy, in that a beam of electrons is passed through a thin slice of sample. The technique measures the slowdown of the electrons that is caused by their interaction with inner-shell electrons in the atoms of the sample. The amount of energy lost in an interaction is characteristic of a specific element. The other technique from Bell Labs being applied to biomedical problems is fluorometric analysis. This technique is already in use to measure lead levels in blood as a test for lead poisoning (C&EN, Feb. 3, 1975, page 18). The technique also can be used to monitor bilirubin levels in the blood of newborns, Dr. Angelo A. Lamola told the Society for Pediatric Research meeting in New York City last week. About 10% of babies, and most that are born prematurely, lack sufficient mechanisms to eliminate bilirubin, a breakdown product of the blood protein hemoglobin. If bilirubin levels build up beyond the blood's carrying capacity for the

Bell Labs photoanalytic Instrument helps determine risk of brain damage to baby 8

C&EN May 1, 1978

compound, it can enter the brain and cause irreversible brain damage. When bilirubin is either bound to blood albumin or treated with a detergent, it will fluoresce when exposed to blue light. For the test, the degree of fluorescence of one drop of blood is measured "straight" to determine bound bilirubin. Another drop is treated with detergent to measure unbound bilirubin, and the third is combined with excess bilirubin salt to measure any unoccupied bilirubin binding sites in the blood sample. D

Nader, activist groups blast energy program President Carter's honeymoon with at least one of the identifiable constituencies that helped elect him may be rapidly coming to an end. Last week Ralph Nader and a coalition of environmental and "consumer" issue activists lashed out at the Administration's energy program and warned ominously that if Carter didn't come around to their way of thinking they might just start thinking about someone else to support in 1980. In a prepared statement, the group declared that "we have waited patiently and silently for most of this past year. We have waited for this Administration to fulfill—or begin to fulfill—its oft repeated promises." Carter campaigned on an energy platform that subordinated nuclear energy to last resort status, while simultaneously committing himself to energy conservation and boosting soft energy technologies such as solar power. "Instead [the Administration] is devoting its imagination, enthusiasm and commitment to nuclear power, to massive subsidies for development of synthetic fuels." The group singles out as a major culprit energy chief James R. Schlesinger, whom the group denounces as "backsliding every day to the worn-out, inadequate energy policies of the Republican Administration in which he served." The coalition contends that Schlesinger is pro-industry in forming energy policies. To regain the favor of the environmental groups, the coalition declares that, among other things, the Administration must give up its plans to promote greater use of nuclear power and redirect federal energy R&D to give renewable energy resource development the highest priority. Otherwise, warns Anthony Z. Roisman, a lawyer for the Natural Resources Defense Council, "a lot of people are going to have to think about who they'11 support in 1980." D