duced a hydrogen plasma contain­ment of 10,000 billion seconds per cc in a Tokamak "magnetic bottle" confinement system called Alcator. A Tokamak system, originally de­veloped in the Soviet Union, is a toroidal, or closed, magnetic con­tainment device.

Plasma containment is expressed as the product of plasma density and plasma confinement time. ''This quantity is a critically im­portant measure of success for fusion," Seamans says. "The Alca­tor result exceeds by a factor of five anything previously achieved any­where in the world, and it is 10 times better than previous typical levels."

Plasma containment at MIT was accomplished at about 10 million degrees Celsius. And, according to ERDA, it was "almost completely devoid of unwanted impurities." Seamans says that the MIT work is an important step toward ERDA's goal of building a demonstration fusion power plant by the end of the century.

Although the MIT work is a major advance, other problems will have to be solved before fusion power is a reality. For example, the density/ confinement time will have to be in­creased by a factor of 10 to 30. Also, plasma temperatures of more than 100 million degrees Celsius will be required before a controlled fusion reaction can be "ignited" success­fully.

Temperatures in excess of 100 million degrees Celsius have been produced previously in laboratories, but for considerably shorter periods of time. For example, scientists at the University of California's Lawrence Livermore Laboratory produced a confinement tempera­ture of 130 million degrees Celsius in July with a magnetic mirror, or open, fusion experiment.

Achieving the requisite time and temperature conditions for fusion power simultaneously will require new and larger equipment. Several units now are under construction or are being planned.

One is the Princeton Large Torus at Princeton University that will start up next month to further refine plasma confinement. Another is the Doublet III being built at General Atomic Co., La Jolla, Calif. This unit is expected to be able to achieve the simultaneous fusion reaction conditions needed to initi­ate a controlled fusion reaction but will use a nonfusable hydrogen/ deuterium fuel for test purposes. Finally, a Tokamak test reactor is planned for 1981 at Princeton Uni­versity that will use deuterium/ tritium fuel. D

Study reveals trends in corporate giving Manufacturing companies, includ­ing those that make chemicals, ap­parently are donating a sharply de­creasing share of their earnings to aid education. Fresh evidence of this trend came last week from the Council for Financial Aid to Edu­cation. The council is a nonprofit group based in New York City. Its chairman is John T. Connor, chair­man of Allied Chemical.

The council conducted a survey

Firms donate decreasing share of profits to schools % of ore-tax net income

1964 1966 1968 1970 1972 1974

Source: Council for Financial Aid to Education

of 799 U.S. companies jointly with the Conference Board, a nonprofit business research organization also based in New York City. The study reveals that the 50 chemical makers covered in the report pushed up ed­ucational aid to $22 million in 1974. This is 11% higher than in 1972. However, this dollar level has changed little since the mid-1960's and it represents a decrease as a percentage of pre-tax earnings. This percentage has dropped by half, from 0.48% in 1966 to 0.24% in 1974.

Manufacturing companies as a group have paralleled this perfor­mance by chemical makers over the past decade—the percentage of pre­tax earnings going to higher edu­cation from all such firms dropping from 0.40% in 1964 to 0.17% in 1974.

Even so, both chemical makers and manufacturers as a group favor education quite strongly for their donations. In 1974, education got 40% of the contributions from man­ufacturers and 46% of those from chemical makers. By contrast, edu­cation's part of the total contribu­tions of all 799 companies in the joint survey was 35% in 1974.

The survey brings out that the

total contributions to education by all the firms covered in the 1974 survey reached $445 million. This was 9% higher than the level in 1973, and it represents the fourth consecutive year in which a new all-time high has been set. Even so, the 1974 total was the equivalent of 0.32% of pre-tax earnings, down from 0.41% in 1971.

The council notes that its figures are not strictly comparable from year to year, because of variations in the number of companies cov­ered. However, the overall decline that it reveals in educational dona­tions from manufacturers is real and unmistakable. G

Nuclear power plant safe at any speed The Nuclear Regulatory Commis­sion has released a report apparent­ly intended to settle once and for all the question of the safety of the nuclear power reactors now in use. And according to the report—An Assessment of Accident Risks in U.S. Commercial Nuclear Power Plants—the risks to the general public involved in the operation of nuclear power plants are very low indeed.

In fact, a person has much more chance of dying or being injured from man-made or natural causes than from a nuclear reactor acci­dent. In a year, according to the re­port's calculations, chances of dying in an automobile accident are 1 in 4000; in a fire, 1 in 25,000; or in a hurricane, 1 in 2.5 million. Whereas, chances of dying as a re­sult of a nuclear reactor accident are only 1 in 5 billion.

Dr. Norman C. Rasmussen of Massachusetts Institute of Tech­nology's department of nuclear en­gineering, who directed the NRC study, says that the report shows that the risks associated with a possible nuclear reactor accident are very small in terms of risks nor­mally accepted by the public. But he points out that the report makes no judgment on the acceptability of nuclear risks, since that judgment must be made by a broad segment of society.

For example, the report esti­mates the chances of a very large accident—one that would result in 1000 or more fatalities—occurring is 1 in 1 million per year. For the 10 million people who might receive some exposure in such an accident, the normal incidence of latent can­cers would increase only from 17,000 to 17,170. The incidence of

Nov. 10, 1975C&EN 7