More Electricity from Heat - C&EN Global Enterprise (ACS Publications)

Nov 6, 2010 - The device, called a plasma thermocouple, bears some resemblance to General Electrics thermionic converter (C&EN, Dec. 2, 1957, page 22)...
0 downloads 0 Views 183KB Size
static tandem, except for two ISO de­ gree magnets. These magnets are to bend the final beam, bringing it back to the negative ion source region. Here, it is accelerated u p to the high voltage terminal of the first seetion. In this setup, the test area winds u p in the first high voltage terminal area. But this is not so simple as it sounds, experts point out. While rigging up a target inside the high voltage terminal is by no means impossible, it t*ertainl\ is a w k w a r d and requires some pains­

taking design work. Van tie Craaff says. • Not Far Off· Most conference members shared Van d e Craalf's confi­ dence that three-stage tandems a r e a nuclear research tool of the not-toodistant future. But m u m \ oiced skep­ ticism about the feasibility of t h e four stage setup. It is sound in principle. the> concur. But is it practical in light of the delicate job necessar\ to line up the magnets and target accurate!) ? Is this extra energy output needed at present?

ANNOUNCING OPENING OF HOUSTON OFFICE

M o r e Electricity f r o m H e a t Los A l a m o s scientists d e v e l o p p l a s m a t h e r m o ­ c o u p l e ; t h e o r e t i c a l c o n v e r s i o n efficiency is o v e r 3 Q % ./Y c.HOLP of fixe scientists at Los Alamos National Laboratory. Los Alamos, N. M., have come u p with a new wrinkle in direct conversion of heat to electricity (C&KX, \ o \ . 3 , page 19). T h e device, called a plasma thermocouple, bears some resemblance to General Electrics thermionic con­ verter ( C & E X , Dec. 2, 1957, page 22) but has some important differences. T h e plasma thermocouple replaces the standard metal-metal junction of a thermocouple with a metal-plasma junc­ tion. It is theoretically capable of con­ verting heat to electricity with an effi­

ciency of 30'< or better, according to calculations by two Los Alamos con­ sultants. The best the Los Alamos team has done to date, however, is 5 ' ? . • Cesium Used. T h e plasma is gen­ erated when heat from the heat source ionizes cesium \ apor in a cell at a pres­ sure of from 0 . 1 - to 2-mm. mercury. Cesium is used because it vaporizes at a low t e m p e r a t u r e ( 6 7 0 ° C.) and, more important, because it has the lowest ionization potential (3.88 volts) of any element. But there are other possibili­ ties—rubidium, potassium, sodium, and lithium, for example.

To further expand its service to the chemical and petrochemical industriels, (.irdler Catalysts, Chemical Products Division of Chemetron Corporation has established a n oliice a t 4007 Rellaire Bhil, Houston 26, under the direction of Merle R. l i k e n s . Telephone number is Mohawk 4-3987.

...another service - i m p r o v e m e n t of

GIRDLER CATALYSIS

HOT ELECTRIC CURRENT

CHEMICAL PRODUCTS DIVISION CHEMETRON

CORPORATION

Louisville 1, Kentucky Telephone: Spring 8-4421

PLASMA

METAL COLD PLASMA

THERMOCOUPLE

This schematic shows a plasma t h e r m o c o u p l e capable of converting h e a t t o electricity with a theoretical efficiency" of 3 0 % . T h e plasma thermocouple uses one metal plus a gas instead of t w o metals used in n o r m a l thermocouples

PROBLEM SOLVER - -. 40-poge data book to facilitate studies of chemical reactions as on aid to selection of catalysts. Mail coupon for Sulfetm G245A. GIRDLER CATALYSTS CHEMICAL PRODUCTS DIVISION P. 0. Box 337 Louisville 1, Kentucky Send free copy of Data Book G245A. Company Name Company Address .. City Zone_ Your Name _ Position _.

NOV.

10.

19 58

— State __

C &ΕΝ

53

RESEARCH

EDUARD

BUCHNER • Bdukrd Buchner's epoch-making research in the fundamentals of fermentation, which established the fact that alcoholic fermentation could take place without the presence of yeast cells, earned Jbim the Nobel Prize in 1907.

NewText

Mk JfWl flfeSBn

" f O R È M O S I

^

r

?amPÎes ar*d specifications, write Dept. Λ\

K O O D

New Text

A N D C H E M I C A L C O M P A N Y

P. 0 . Box 539, Oakland 4, CaHfornîà

BOSTON 'Λ /ATLANTA, - - CHICAGO . CINCINNATI CLEVELAND 8. S . Wilson & Sons &t 8. Sweel Co. Howard Dock F.W.KaminCo. '7; ν Geo.£;Missbach.&C0. , HOUSTON KANSAS CITY MINNEAPOLIS ϊ/λ:/DETROIT NEW ORLEANS Vulcan Sates Co. M. H. Baker Co. Breffeiih & Sheahan Co. Joe Coulson Co. -~fy Harry Holland & Son, Γης. ; OKLAHOMA CITY 6AKLAND S L LOUIS NEW YORK Foremost Food & Chemical Co. H. ReisiTian Co. Ruilman Brothers Harry hi Baumstark & Col

54

C * ΕΝ

N O V . ΙΟ.

1958

New Help for Lubes Additives m a k e silicone l u b ­ ricants more effective a t high temperatures

• By 1907, Foremost's El Dorado Division was already a prize supplier of coconut oil and its by-products to American industry. El Dorado is still foremost in the purity and uniformity of its products.

aSm « Β

In the prototype, the electrode iii the hot end of the plasma is tanliclum. al­ though the researcher!» are investigating other materials, ('tipper and t-utitulum both have worked well in the cold e n d . Typical temperature of the pl-asma at the licit end is 2600 C ; at the cold e n d . 300 C. Resulting potential i s about «me millivolt per degree of tempera­ ture difference between the liot a n d cold ends; this means that t> pical vnltages that Los Alamos obtained are about 2 volts. An important advantage ol the plasma thermocouple over a vacuum cell (such as the thermionic converter » or a semiconducter thermocouple is the low impedance ol the plasma. .-Kndw ith its device, the Los Alamos group has been able to generate electricity con­ tinuously when it has put in L\ steady amount of heat. The research team, headed l>yC. M. Grover, has not yet tried to reach effi­ ciencies even approaching tlu>se theo­ retically possible», but it is continuing its studies. (anient tests are aimed at developing a plasma thermopile- that is, a unit which will convert the heat generated by fission directly to elcctricitv.

A NEW approach to develop ment of antioxidants for high temperature luhrieants has turned up a group ol con­ densed four- and five-ring aromatic compounds that hold viscosity increase in fluid silicone lubricants to only a moderate amount at tempera, tines as high as 550 F. How ever, Stanford Research Institute, which did the work, found no antioxidants that were effec­ tive on mineral oil. silane fluid, or syn­ thetic ester lubricants. Eilectivencss of the antioxidants was measured by reduction in viscosity increase com­ pared with a blank. Using General Electric's F-5C silicone fluid, condensed ring aromatic com­ pounds held the viscosity increase to only a moderate amount during; the test period. In blank experiments without an additive, the fluid was completely