R E A C T IO N K IN E T IC S 541.121/.128
541.124 : 542.943 1945
T he o x idation o f liquid hydrocarbons. I. T he chain form ation o f hydroperoxides and th eir decom position.
George, P ., Rideal, E . K ., and Robertson, A.
Proc. R oy. Soc. A , 185, 288-309 (M arch 14, 1946).
541.124 : 542.943 1946
T he oxidation o f liquid hydrocarbons. I I . The cncrgy-chain m echanism fo r the therm al oxidation o f tetralin . George, P ., and Robertson, A . Proc. R oy. Soc. A , 185, 309-36 (M arch 14, 1946).
541.124 : 542.943 1947
T he oxidation o f liquid hydrocarbons. II I . T he oxidation o f tetralin in the presence o f benzoyl peroxide a s a free radical chain reaction George, P. Proc.
R o y. Soc. A , 185, 337-51 (M arch 14, 1946).
541.124.7 : 537.568 see Abstr. 1905
541.126 1948
T he m echanism o f the hydrogen-oxygen reaction.
I. T he third explosion lim it. I I . T he reaction occurring between the second and third explosion lim its. III. T he influence o f salts. Willbourn, A . H., and Htnshel- wood, C. N . Proc. R oy. Soc. A, 185, 353-80 (A pril 5, 1946).—T h e influence o n th e th ird lim it o f (a) hydrogen-oxygen p ro p o rtio n s , (b) a d d itio n s o f N j, C 0 2 a n d steam w ere e xam ined, th e m easu rem en ts being m ad e m ainly a t 586°c in a silica vessel c o ated w ith KC1, w hich co n tro ls th e reactio n ch ain s. T h e results agree qualitatively, w ith the th eo ry th a t th e th ird lim it dep en d s u p o n th e b ran ch in g o f re ac tio n ch ain s. A n expression is derived fo r th e ra te o f fo rm atio n o f w ater in th e steady sta te a n d this lead s 210
lo a satisfacto ry d e scrip tio n o f th e th ird lim it. In II experim ents a re d escrib ed o n th e ra te o f 'r e a c ti o n betw een H 2 a n d 0 2 a t p ressures lying betw een the seco n d a n d th ird ex p lo sio n lim its. T h e eq u a tio n for th e ra te o f co m b in a tio n o f H 2 a n d 0 2 is facto rized by c o n sid erin g first th e c o n d itio n fo r th e th ird explosion lim it. T h is allow s th e d e te rm in a tio n o f m o st o f the c o n stan ts. W ith th e help o f these resu lts th e ra te e x p ressio n is tested a n d th e fo rm o f th e fu n ctio n d escribing th e initial re actio n is exam ined. It is c o n clu d ed th a t the ch ain s are p ro b a b ly in itiated by th e disso ciatio n o f H 2 : H 2 + M = 2H . In I I I the influence o f KC1, K I, C sC l, Cs, I, etc., o n th e ex
p lo sio n lim its a n d o n th e ra te o f th e re ac tio n o ccu rrin g betw een th e seco n d a n d th ird lim its is exam ined.
Iodides differ g reatly fro m th e o th e r halides. T he effect o f the salts is p ro b a b ly d u e to specific chem ical
in teractio n s. l. s. g.
541.126.2 1949
In itia l stag es o f the explosion o f nitroglycerine.
Vines, R . G., and Mulcahy, M. F . R . Nature, Loud., 157, 626 {M a y 11, 1946).— T h e d e to n a tio n o f a th in lay er o f n itroglycerine confined betw een a glass a n d a' b rass sh e e t w as p h o to g ra p h e d o n a ro ta tin g d ru n T cam cra. T w o d istin ct stages in th e sp re ad o f t h e ex p lo sio n co u ld b e d etected, co rresp o n d in g to velocities o f p ro p a g atio n o f 400 a n d 2 000 m /sec respectively. W ith a th ic k lay er a n initial very fast (5 000 m /sec) process w as also a p p are n t.
E L E C T R O C H E M IS T R Y 541.13
5 4 1 .1 3 3 :5 3 7 .3 1 2 .5 1950
E lectronic processes in liquid dielectric media.
P ro p erties o f m etal-am m onia solutions. O g g , R . A ., J r . J. A m er, Client. Soc., 68, 155 {Jan., 1946).—
E xtrem ely d ilute liq u id N H 3 so lu tio n s o f m etallic N a sh o w a m ark e d in crease in electrical c o n ductivity u p o n irra d ia tio n w ith visible lig h t. T h is effect was o b serv ed in th e tem p e ra tu re ra n g e —35 to — 75°c.
T h e q u a n tu m efficiency o f th is p h o to -co n d u ctiv ity is a n inverse fu n ctio n o f th e co n ce n tra tio n o f th e so lu tio n a n d th u s w ith re aso n a b le lig h t intensities, th e effect is ex p erim en tally observ ab le o n ly a t lo w co n cen tratio n s o f th e o rd e r o f 10~3m. D ilato m etric m easurem ents a t — 35°c, in w h ich m etallic N a w as ex tracted from so lu tio n s o f a b o u t 3 x 10_3m ind ic ated a volum e ch an g e o f ap p ro x im ately 700 cn ri/m o lc o f solute.
T h e q u a n tu m m echanical c o n sid eratio n s lead to the con clu sio n s, (a) th a t th e g ro u n d sta te o f th e system is a n “ S” sta te o f to ta l energy —4 800 cal/m o le in a c av ity o f ra d iu s 7 -6 x 10-8 cm ; (b) all o th e r states a re u n sta b le ; (c) p h o to -co n d u c tiv ity follow s a tran si
tio n fro m th e g ro u n d sta te to th e low est “ P ” state;
a n d {d) tw o electro n s tra p p e d in th e sam e cavity are ap p reciab ly stable w ith respect to eith er tw o electrons, in se p arate cavities o r o n e tra p p e d a n d o n e c o n d u c tin g electron. T h e a b so rp tio n sp e ctru m an d m agnetic susceptibility o f m etal a m m o n ia so lu tio n s a re in a t least q u alitativ e ag reem en t w ith these c alcu latio n s. [See A b s tr. 1894 (1946)]. w . r. a.
541.134 1951
R eproducibility o f the lead electrode and the e le ctro m otive force o f the lead stick -lead am algam cell a t 0° to 60°C. Bates, R . G ., Edelstein, M ., and
Acree, S. F . J. Res. N at. Bur. Stand., Wash., 36, 159-70 {Feb., 1946).—T h e p o ten tials o f 4 types o f so lid P b electrodes w ith resp ect to s a tu ra te d P b am a lg am w ere o b tain ed . A lth o u g h P b a n n eals sp o n tan eo u sly , th e surface c o n d itio n h a s a p ro fo u n d effect u p o n th e electrom otive force. U n tre a te d P b sticks w ere, in general, positive to P b th e surface o f w hich h a d been ren d ered strain-free. W h en e tc h ed in a m ix tu re o f nitric acid a n d P b n itra te, th ese sticks so o n reac h ed th e sam e p o ten tial. R em oval o f a ir fro m th e so lu tio n s im p ro v ed th e agreem ent a m o n g th e electrodes. T h e difference o f p o ten tial betw een stick lead a n d 8% P b am algam a t in terv als o f 5° fro m 0° to 60°c is given by th e eq u a tio n E = 0-005347 4- 0-0000201/, w here E is th e electrom otive force in in te rn atio n al volts a n d t is in degrees centigrade.
T h erm o d y n am ic c o n stan ts w ere c o m p u te d fro m th e te m p e ra tu re coefficient o f electro m o tiv e force.
P H O T O C H E M IS T R Y 5 4 1 .1 4
541.141.1 1952
T he quantum yield in the photo-reaction between m ethyl iodide and n itric oxide. Iredale, T ., and McCartney, E . R . J. A m er. Chetn, Soc., 68, 144-5 {Jan., 1946).— W hen th e n itric oxide p ressu re is above 50 m m th e q u a n tu m yield reaches a v alu e betw een 0 -9 a n d 1 -2. T h is degree o f accuracy o f th e experi
m ental results perm its th e a d o p tio n o f th e in te r
p re ta tio n o f th e re ac tio n as C H 3I —> C H 3 4- I, C H 3 + N O - > C H jN O , I + I - > I 2. T h e back reactio n s, C H 3 4- I 2- > C.H3I + I, a n d C H 3 + I - >
C H 3I, begin to low er th e q u a n tu m yield o n ly w hen th e n itric o xide pressure is lo w .. T h e iodine form ed w as frozen o u t a n d titra te d w ith app ro x im ately 0 -0 0 5 n th io su lp h ate. T h e C H 3N O o r its decom posi
tio n p ro d u c t w as n o t identifiable. w. r. a. 541.141.7 : 535.343.4 see Abstr. 1860
541.148 : 541.183.55 see A bstr. 1955
C O L L O ID S . A D S O R P T IO N 541.18 541.18 : 532.582.7 see A bstr. 1815
541.182.2.053.: 532.529 see A bstr. 1814
541.182.6 1953
T heory o f the stab ility o f lyophobic colloids. Ver- wey, E . J. W . Philips Res. R ep., 1, 33M 9 {O ct., 1945).— T h e forces actin g betw een colloidal p articles a re a ssum ed to be d u e to a su p erp o sitio n o f a n a ttractiv e p o ten tia l c au sed by van d er W aa ls -L o n d o n forces, a n d a d o u b le lay er in te ra c tio n p o ten tial c au sed by th e in te rp e n e tratio n o f th e diffuse charges o f th e electrical d o u b le layers su rro u n d in g th e p articles in th e liq u id . It is assu m ed th a t th e d o u b le lay er p o te n tial is in d ep en d en t o f th e electrolyte co n c e n tra tio n a n d th a t it rem ain s c o n s ta n t w h en tw o particles m eet. A general exp ressio n fo r th e free energy o f a d o u b le lay er o r a d o u b le lay er system is derived, a n d fro m this a n e x p ressio n fo r th e in te ra c tio n p o ten tia l VR c an be o b tain ed . T h e resu lt o f the d o u b le layer in te ra c tio n is alw ays a rep u lsio n . In c o m b in a tio n w ith th e v an d e r W a a ls -L o n d o n attra c tiv e p o ten tial VA th is leads to to ta l p o te n tia l curves o f tw o types: {a) curves sho w in g a m axim um c o rresp o n d in g to positive values o f VR 4- VA, a n d
541.183 545.82
(b) curves fo r w hich VR + VA is everyw here negative.
T h e fo rm er type w o u ld c o rre sp o n d ro u g h ly to stab le sols o r suspensions. T h e th eo ry gives a q u a n titativ e e x p lan atio n o f th e S ch u lze-H a rd y ru le, a n d show s th a t u n d e r certain c o n d itio n s th e flocculation values o f m o novalent, div alen t a n d triv a len t io n s w ill be as 1 : ( i ) 6 : ( i ) 6- T h e v alu e fo u n d fo r th e v an der W aa ls -L o n d o n co n stan t agrees well w ith th e value p redicted by q u a n tu m theory.
541.183 1954
The equilibrium spreading pressure o f oleic acid and o f ethyl sebacate on concentrated salt solutions.
Donnison, J. A., and Heymann, E. Trans. Faraday Soc., 42, 1-5 {Jan.-Feb., 1946).— In all cases,' except th a t o f p o tassiu m fluoride, salts increase the eq u i
lib riu m sp reading p ressu re w ith increasing activity, giving an ap p ro x im ately lin e a r re la tio n in th e o rd er o f decreasing energy o f h y d ra tio n , viz.:
L i < N a < K < R b , a n d F < C l < B r < I < C N S.
H ow ever, in th e case o f ethyl sebacate, th e b eh av io u r o f th e catio n s is irregular. T h e results a re discussed visualizing tw o effects: (a) a n increase o f th e a ttra c tio n betw een th e o rg an ic m olecules a n d th e su b strate;
(6) an increase o f th e repulsive term s in th e system o f forces betw een th e m olecules o f th e film. B o th effects are d u e to th e presence o f ions in th e “ film p h ase” a n d w ill increase w ith decreasing energy o f h y d ra tio n o f th e ions.
541.183.55 : 541.148 1955
P hoto-adsorption effects in the system pigment-fluid phase. Hedvall, J. A., and Nord, S. A rk. K em i M in. Geol., 17 A (No. 3) Paper 11, 11 p p . (1943).—
M easu rem en ts a re re p o rte d o f the a d so rp tio n o f p h th alcin s by suspensions o f re d a n d black H gS a n d b y C dS u n d e r irra d ia tio n a n d in darkness.
R esu lts in d icate th a t th e d im in u tio n o f c o n cen tratio n in the susp en sio n s ex p o sed to lig h t is d u e to a p h o to a d so rp tio n effect. T h e black H gS show s sim ilar ad so rp tio n cap acity in lig h t o r d a rk n ess, b u t th e re d H gS ad so rb s u p to 6 tim es as m u ch phen o lp h th alein in light as in d ark n ess. T h is difference m u st be co n nected w ith th e electronic stru c tu re o f th e tw o form s.
T h e ch an g e in surface activity th ro u g h ad d itio n o r rem oval o f a n excess o f one o f th e co m p o n en ts is evident in th e H gS a n d in C dS . T h e possibility o f a n analogy betw een th e B ecquercl o r p h o to -v o ltaic effect a n d th e p h o to -ad s o rp tio n effect is discussed.
N. M. B.
541.185 : 778.31 1956
Light-field ultram icrophotograpliy o f lyogels.
Hauser, E. A ., and Le Beau, D . S. J. A m er. Chem.
Soc., 68, 153-4 (Jan., 1946). S ee also Industr. and Engng Chem., 38, 335-8 (M arch, 1946).— A n u m b er o f c o lo u r p h o to g rap h s have b e en m ad e o f lyogels u sing K o d a ch ro m e A film. T h e absence o f an y g rain in th e developed film p erm its o f co nsiderable enlarge
m ent. E nlargem ents have been m ad e o n re g u la r p rin tin g p ap er usin g th e K o d a c h ro m e p ictu re as negative, a n d the resulting positive is term ed the
“ light-field u ltra m ic ro g rap h ” since it is really a reversed u ltram icroscopic effect. T h is tech n iq u e enables a satisfacto ry p rin t to be o b ta in e d fro m th e c o lo u r slide w herever a specific c o lo u r is n o t th e p re d o m in an t fa c to r in th e stu d y o f th e p re p ara tio n .
A sim ilar resu lt c a n b e o b tain e d w ith o u t using K o d a c h ro m e if th e d ark-field negative is exposed to a film a n d th e resu ltin g positive used fo r m ak in g th e
p rin ts. w . r. a.
C H E M IC A L S T R U C T U R E 541.2/.6
541.5 1957
T he electronic theory o f valency. Anantha- krishnan, S. V. Curr. Sci., 15, 33-5 (Feb., 1946).—
P roceedings o f a sym posium a t th e A n n u a l M eetin g o f th e In d ia n A cadem y o f Sciences, a t U d a ip u r, D e c., 1945.
541.57 : 536.413 : 536.763/.764 : 584.73 see A bstr. 1967
541.57 : 539.133 1958
M olecular constants and chem ical theories. V. Som e rem ark s on physical constants aiid theories o f higher valenccT states. Sa m u e l, R . J. Chem. Phys., 13, 572-84 (D ec., 1945).— R eplies to criticism [see A b str.
2512 (1945)] o f th e a u th o r’s e arlie r p a p ers [see A b str.
2514 (1945)].
541.57 : 539.133 see A bstr. 1921
541.612 -19 5 9
T he sta tistica l length o f long-chain molecules.
Treloar, L. R . G . Trans. Faraday Soc., 42, 77-82 (Jan.-Feb., 1946).— A "fo rm u la is derived fo r th e com plete fu n c tio n rep resen tin g th e p ro b a b ility o f a given distance betw een th e en d s o f a ch ain o f u n i
versally jo in te d e q u al links. T h e fo rm u la is c o m p u te d fo r ch ain s o f 25 a n d 100 lin k s. T h e d istrib u tio n fu n ctio n s d erived fro m th is fo rm u la are c o m p ared w ith th o se previously w o rk ed o u t b y a n in d ep en d en t m eth o d fo r p o lyisoprene a n d paraffin ch ain s. I t is sh o w n th at th e p o lyisoprene ch ain is statistically equivalent to a ra n d o m ly -jo in ted ch ain o f len g th co rresp o n d in g to 1 -42 lin k s p e r iso p ren e un it.
541.68 : 539.31 see A bstr. 1940 541.68 : 539.374 see A bstr. 1942
C H E M IC A L P R O C E S S E S 542 542.943 : 541.124 see A bstr. 1945-1947
C H E M IC A L A N A L Y S IS 543/545
545.8 i960
Q u an titativ e analysis by the variation o f the specific activity o f an added radioactive isotope. Sue, P.
N ature, Lond., 157, 622 (M a y 11, 1946).
545.81 : 531.717 see A bstr. 1802
545.82 : 535.34-15 1961
R ecording infra-red analysers for butadiene and styrene p lan t stream s. Wright, N ., and Herscher, L. W . J. O pt. Soc. A m er., 3 6 ,1 9 5 -2 0 2 (April, 1946).—
O ptically th e in stru m e n t consists o f a d o u b le b eam system em ploying a single source o f ra d ia tio n , a split lens o r m irro r, a sam ple cell a n d v ario u s filters th ro u g h w h ich o n e o r b o th beam s m ay pass, a n d tw o electrically o p p o sed d etecto rs u p o n w hich th e beam s a re focused.
Selectivity o f w avelength is p ro v id ed by th e filters a n d by d etecto rs h av in g selectively ab so rb in g ra d ia tio n receivers. T h e d etecto rs a rc tw o o p p o sed arm s o f a n a.c. excited b o lo m e ter m ad e o f fine n ickel w ire em -212
548.73
bedded in a selectively a b so rb in g m edium . O p e ratio n o n p lan t stream s o f b u tad ien e-b u ten c gas m ixtures
548.0 : 539.31 : 537.228.1 = 3 1962
O n the piezoelectric A C -eflect o f Rochelle salt [S eig n ette] dielectrics. Matthias, B. H elv. Phys.
A cta, 16 (No. 2) 99-135 (1943) In Gentian.— A theory is given o f th e a n o m a lo u s elastic b eh av io u r o f Seignette dielectrics. T h e a p p a ra tu s a n d m eth o d o f m easu rin g th e p u re A E-effect a n d th e d a m p in g are described a n d th e results o f som e ex p erim en ts are d iscussed in
re la tio n to the theory. L. s. G.
548.12 = 4 1963
O n “ double” crystallographic groups. Opechowski, W . Physica, ’.v Grav., 7, 552-62 (June, 1940) In French.—T h e concept o f “ d o u b le g ro u p ,” in tro d u ced by B eth e [A bstr. 892 (1930)], is defined precisely by rep resen tin g th e g ro u p o f ro ta tio n s in term s o f a gro u p o f tran s fo rm a tio n s o f tw o com plex variables. T he general th eo ry is ap p lied to tetrah e d ra l a n d rh o m b o - hedral gro u p s, a n d p articu larly to th e p e rtu rb a tio n o f a sta te o f q u a n tu m n u m b e r J by fields w ith these
sym m etries. a. j. c. w.
548.524 : 669.6 = 393 1964
Form ation o f tin crystals. Brandsma, W . F ., and Stap, M . Physica, 's Grav., 10, 790 4 (D ec., 1943) In Dutch.— L iquid Sn w as allow ed to solidify p artially in a cast-iro n m o u ld , th e rem ain in g liquid being ru n off. T h e crystal fo rm atio n w as stu d ied at v arious rates o f cooling. G ro w th tak es place by d en d rite- fo rm atio n in th e basal plane, th e directio n s o f fastest g ro w th bein g th e base diag o n als. T h e crystals arc th u s plates p erp en d icu lar to th e te trag o n al axis, b u t
so m ew h at im perfect. a. j. c. w.
548.572 1965
C leavage o f calcite. Tolansky, S., and Kham- savi, A . Nature, Loud., 157, 661-2 (M a y 18, 1946).—
O p tical interference m eth o d s w ere used fo r the e x am in atio n o f th e cleavage faces. E vidence is fo u n d fo r som e fo rm o f co arse m osaic block stru ctu re.
548.73 1966
O n the crystal structure o f phthalim ide. I. D e te r
m ination o f the space-group. Bagcht, S. N ., and Kasem, M.. A . Indian J. Phys., 19, 93-6 (June, 1945).— T h e axial ra tio s, o b ta in e d from X -ray studies, a re a : b : c — 2-98 : 1 : 0-4946. T h e space g ro u p is C 52/t— P 2 ,/h .
548.73 : 536.413 : 536.763/.764 : 541.57 1967 S tru ctu re and therm al properties o f crystals. V I. T he role o f hydrogen bonds in Rochelle salt. Ubbelohde, A. R ., and Woodward, I. Proc. Roy. Soc. A , 185, 448-65 (A pril 5, 1946).— X -ray m easu rem en ts o f changes in th e lattice spacings o f R o ch elle salt betw een — 90°c a n d 40°c were m ade, a n d th e th erm al pro p erties w ere co rre late d w ith crystal stru ctu re.
T h erm al ex p an sio n is largest in th e d irectio n o f the h y d ro g en b o n d s, b u t th is p red o m in an c e largely d isap p ears above th e u p p e r C urie p o in t. Betw een th e tw o C urie p o in ts, —20° an d 2 4 -5 °c, th e therm al ex p an sio n is a n o m a lo u s an d th ere is a hysteresis
a n d o f styrene-ethyl-benzene liq u id m ixtures is detailed.
effect. T h e th erm o d y n am ic changes a t th e u p p e r an d low er C urie po in ts a re discussed o n th e basis o f th e experim ental d ata. X -ray evidence show s th at over th e tran sitio n range o f tem peratures m easurable differences c a n be detected betw een subcrystalline d o m ain s w ith in a “ single” crystal. T hese differences reach a m axim um in c ertain d irections in th e crystal b u t a re insufficient to cause it to b re ak u p in to a pow der, w ith change o f phase, a t th e tw o C urie points, so th a t m o st o f th e p roperties o f a single crystal are re ta in e d o v er th e w hole range o f tem p eratu res. T he o nset o f an o m alo u s dielectric p ro p erties at th e low er C u rie p o in t is ascribed to th e stre tch in g o f sh o rt hydrogen b o n d s ow ing to th e therm al expansion o f the crystal. T h is changes th e b o nds from a p o lar to
a n o n -p o lar ch aracter. l. s. g.
548.73 : 538.221 1968
The stru ctu re o f cubanitc, C uFe
2
S3
, and the coordination o f ferrom agnetic iron. Buerger, M . J.
J. Am cr. Chetn. Soc., 67,2056 (Nov., 1945).— C u b an ite, w hich is ferrom agnetic a n d o rth o rh o m b ic , has space g ro u p Pcmn; th e cell, c o n ta in in g fo u r m olecules, has a = 6-45, 6 = 11 -095 an d c — 6-221 kX . By using intensity d a ta fro m W eissenberg p h o to g rap h s the stru c tu re consists o f C u ato m s a n d o n e-th ird o f the S a to m s a t th e eq u ip o in t 4c, w hilst the Fe a to m s and th e rest o f th e S ato m s are in the general positio n 8<7.
A p p ro x im ate p aram eters have been determ ined.
T h e m etals a re each su rro u n d e d by fo u r S ato m s in alm ost u n d isto rte d tetrah ed ral c o -o rd in atio n , and S ato m s a re su rro u n d ed by fo u r m etals in tetrah ed ral c o -o rd in a tio n . T h e stru c tu re m ay be regarded as m ad e u p o f vertical slices o f the w urtzite a rran g em en t jo in e d to identical b u t inv erted slices by m eans o f the sh a rin g o f o n e o f th e edges o f e ach F e co -o rd in atio n te trah e d ro n . T h u s th e F e ato m s a re b ro u g h t to g eth er in p a irs across th e sh a red edges, a n d suggests th at the F e a to m s are linked to o n e a n o th e r in pairs as well as bein g linked to fo u r S ato m s; an d th is unu su al linking ap p ears to be the cause o f th e ferrom agnetism
o f th e cry stal. w . r. a.
548.73 : 669.65 1969
X -ra y studies o f binary alloys o f tin with transition m etals. Nial, O. Univ. Stockholm Inaug. Diss., 103 pp. (1945).— T h e system s stu d ied a re F e -S n , C o -S n , N i-S n , C r-S n , M n -S n , R u -S n , R h -S n , P d -S n , Ir-S n a n d P t-S n ; a n d in th e case o f rh en iu m a n d osm ium it is found th a t these a re n o t perceptibly soluble in tin. T h e lattice dim en sio n s a re determ ined fo r th e v ario u s ph ases in e ac h system an d th e tem peratu re ranges in w hich th ese phases exist a re found.
N ew e q u ilib riu m diag ram s a re set u p o n th e basis o f th e resu lts o b tain e d . S tru ctu ral an alogies a re d is
cussed. F e 3Sn, N ijS n a n d M n 3Sn b elong to the N i3Sn type, D O ,,. FeSn a n d C oS n b elo n g to the C o S n type B35. I rS n 2 a n d P tS n 2 a re iso m o rp h o u s w ith C a F j. F e S n 2, C o S n 2, M n S n 2 a n d R h S n 2 are a n alo g o u s w ith C uA L . T h e d a ta o f the phases o f the 213
CRYSTALLOGRAPHY 548
548.734.2 550.341.2
seism ological travel-tim e tab les are th eoretically derived fro m specific form s o f th e v a ria tio n o f the551.465
551.50 551.510.535
591.112.3
223-9 (Sept., 1945).— W u ’s suggestion th a t th ere m ay b e a h ig h p re p o n d era n ce o f positiv e io n s in th e E layer [A bstr. 311 (1946)] is sh o w n to b e u n ten a b le, firstly, b e cau se (co n trary to W u ’s su p p o sitio n ) th e dyn am o - th e o ry o f th e .5-field requires, a t m o st, a n excess o f 0-1 charges (1 0 ~ n e.s.u .) o f o n e sign o v er th e charges o f o p p o site sign in a co lu m n 1 cm 2 cross-section d ra w n v ertically in th e E layer; a n d secondly, becau se a co n ce n tra tio n o f p ositive io n s as p o stu late d by W u w o u ld p ro d u c e electric fields so large th a t th e a tm o sp h ere co u ld n o t h o ld to g eth e r u n d e r gravity ag ain st th e m u tu a l rep u lsio n o f its p a rts . v. c . a. f.
5 51.510.5 3 5 :5 5 1 .5 9 4 .1 3 1992
D iffusion o f ions in the ionosphere. Fe r r a r o, V . C . A . Terr. M agn. A tm os. E lect., 50, 215-22 (S ept., 1945).— T h e e q u atio n o f diffusion ap p licab le to th e io n o sp h e re is d eriv ed a fre sh a n d a n e rro r in H u lb u rt’s e arlie r d eriv a tio n [A bstr. 3278 (1928)] is c o rrected . I t is sh o w n th a t in th e E a n d F , layers diffusion is negligible, b u t th a t it begins to be p e r
cep tib le in th e F2 layer. A n a p p ro x im ate in te g ratio n o f th e e q u a tio n o f diffusion is c arrie d o u t o n the su p p o s itio n th a t in th e Ft, layer th e effective coefficient o f re co m b in atio n s is o f th e o rd e r o f 10-10, a n d th a t th e tem p e ra tu re a n d den sity o f th e a ir a re respectively o f th e o rd e r o f 1 000°k a n d 1010 m o lecu les/cm 2. T h e re su lts suggest th a t diffusion low ers th e F , lay er as a w hole by n o t m o re th a n a q u a rte r o f a scale heig h t, w hilst h a rd ly affecting th e m ax im u m electro n density.
v . c . A. F.
551.513 : 550.384 1993
O n th e relation between geom agnetism and the circulatory m otions o f the a ir in the atm osphere.
O n th e relation between geom agnetism and the circulatory m otions o f the a ir in the atm osphere.