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Title : C. Hart Merriam papers : including correspondence, papers relating to career with the United States Biological Survey, 1798-1972 (bulk 1871-1942)
Identifier : chartmerriampape011merr
Contributing Library : The Bancroft Library
Digitizing Sponsor : Sloan Foundation
Click here to view book online to see this illustration in context in a browseable online version of this book.
s^s ^?gppÂ» ff^prrwr yÂ»-rr December 14, 1316 Woodward & Lothrop nth and P ?>t;s., â Teshington Dear oirs: ITill you kir.aiy sand me with the bill the follow- ing books; Eva JI. Tawan: Fem^r and His Friends. Houghton, iiffjin Ho. 60pq Edith B. Davidson: Biimvikins-^iniriGS^Pooks ~ B^^ Bur^ios OhriBtmas Tree; Bunnikms-Boniaes i^i -^^mp 50p each Merrill; 3aEii>el Moose Book. BiP.Dutton & Go^ $3.50 Very truly yours.
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In document Infra red study of lipid water systems
(Page 118-124)

In document Infra red study of lipid water systems
(Page 118-124)

WATER SOLUBLE: SCAPS

40 (°) Beta-prime form

monoglycerides were prepared by Malkins’ method (82), but using di-isopropyl ether in the extraction to

75 cont a.inirig odd numbered chains. (You are here)

bond frequencies in the region 3646-3523cm observed in dilute

85 mole fraction of DpO became two phase at 115°G whilst a sample cont85 mole fraction of DpO was still one phase

The phase behaviour and structure of binary lipid/water systems

Infra Red Search and Track System

The Role and Functions of the Implementation Committee of the School in Improving the Quality of Education

UTILISATION OF INFRA-RED IN RADAR SYSTEM

The Issues of the Judicial System and the Jurisdiction of the Courts of the First Instance in the Republic of Austria

Relativism and Immutability of Values and the Impact of this on the Upbringing of Offspring

Differentiation of the Vegetative and Sporogenous Phases of the Actinomycetes: 1. The Lipid Nature of the Outer Wall of the Aerial Mycelium

Differentiation of the Vegetative and Sporogenous Phases of the Actinomycetes: 2. Factors affecting the Development of the Aerial Mycelium

The spectrum of the sub- phase of IIG18 obtained in this
study is shown in figures 35 and 36 and the earlier spectrum in
figure 38. Similarities are apparent but again there are marked
differences as followss-

i. More structure is observed, in this work, in the
117 0-134 Ocm-■*• region. The bands in this region now have the
appearance of those of a crystalline solid,

ii. The 7 20cm band is now split into two compon
ents at 7 50cm-’*' and 7 21cm-’*’ and the intense single band at

1463cm*"-*-, due to S (CB^)* in. the <=* phase spectrum is now split
into two components at 1406cm"’'*' and 1462cm-’*’, This latter

doublet has not been previously observed in the sub- oC pha.se
of HG18,

The splittings of the 7 20cm ^ and 1463cm*"•*- bands are
thought (99) to arise because of the nearest neighbour CHg
groups interacting to give the out-of-phase and in-phase modes.
This sort of behaviour is found in the highly crystalline

n-paraffins (24) and polyethylene (19?98) and it wan therefore
suggested (90), on the basis of the splitting of the 7 20cm- ’*'
band, that the sub- form had a crystalline lattice (or at

least a very ordered system) possibly of the common orthorhombic
type,

iii. Further evidence of the highly crystalline
nature of the sub- o C form can be seen in the splitting of the
single band associated with "^a( CE^) at 2930cm-’*' in the form,
into two components (table X and figure 36) and the general
intensification and narrowing of the bands in the CH stretch
region compared with the form. This behaviour has not

previously been reported. The components observed here have
similar relative intensities and positions to those found in
triclinic ***-820^/12 (^9) although in that case a further compon
ent was resolved at 2922cm"*1.

iv. In the earlier work (90) a single O(C=.0) band
— 1

has been observed at 1730cm in the sub- oC phase of MG 18

(figure 38). This is a shift to a higher frequency relative to
the oC phase and on the basis of this and the shift of ( OH) to
loY/er frequency upon going from the oC to sub-( OH) is now resolved as two broad comp

onents at 5342cm**1 (main component) and 3243cm"*1.

In this work V ( C s=:0) is resolved as two components at

1739cm**1 and 17 29cm"*1 (figure 37) • The lower frequency compon
ent now has increased intensity compared with the oc and sub-c>C
phases signifying an increase in the participation in the 11-
bonding scheme of this phase. However this component has

moved to a higher frequency relative to the oc. and sub-c* phases
and shows therefore a decrea.se in the E-bond strength. Also

V(OE) is resolved a.s two broad bands at 3408cm"*1 e.nd 3302cm*'1

The behaviour of MG12 upon rehea.ting is more complex than
that of any of the other 1-monoglycerides studied. At transition
C, 26.5°C below the l,c.-oC phase transition (B) a solid is

formed, the spectrum of which is shown as figure 37* The
spectrum is neither that of a sub- ©C , or p T. It has pairs
of bands at 1464cm~^, 1460cm"*1 and 7 23cm“1 , 7 21cm"*1 for £ (CHg)
and />( CH2) modes respectively* The bands in the 1340-1180cm~1
region show a structure similar to the sub~oC , There are seven
components in the CH stretch region (figure 37 t table X) showing
a marked similarity in position and relative intensity to those

of the sub- oC although there is also a component at 2950cm"*
which is not present in the spectrum of the sub- ©C of MG18

Also the \?(0H) band is markedly asymmetric at 3347cm"1
possibly showing the presence of further V (OH) components
whilst that of the sub- oC of T.1G18 is symmetric. The V (C ^ O )
absorption is present as a single component (figure 37) at
17 38cm*" which is in the same position as the higher frequency

*^( C = 0 ) component of the sub-^form, It would therefore

appear that any H-bonding in this phase is taking place solely
between OE groups.

By comparison of the spectrum of this phase with a sub-oC
spectrum of MG18 (figures 35? 36 and 37) it can be seen that
this phase is possibly a modified sub-oC structure with H-bond
ing only talcing place between OH groups.

6) Transition G is due to the melting of the highest

melting or jj form. The p form has been studied extensively
by X-ray (82,85,95,96), infra-red (90,102-105) and P.M.R. (91).
From this evidence it is considered that the crystalline habit
of the p> form is monoclinic with layers of chains tilted at

55° (95) towards the end group plane with chain tilt alternating
in successive double layers.

The spectrum of the form of MG 18 has been previously
reported (90) and is shown as figure 38. The spectrum of (3
form of MG1# from this work is shewn as figures 35 and 36.

Again there are general similarities between the two, however
the spectrum from this work is of a greater resolution and
shows more detail especially in the region 1470-7 00cm"1.

There are seven components in the CH stretch region (figure
36 table X) however it was not possible to compare the intensity
of these with any of the other phases of 1IG18 since the spec
trum was obtained as a nujol mull whilst the others of 1IG18
were obtained by suitable heating cycles. The intensities of
the CH stretch components of the p and p
In the earlier work (90) a single component was observed
for *^(C=:0) at 1736cm**1 in the {3 form of MG 18 and. two bends
were observed for %>(0H) at 3307 cm*"1 and 3243cm*"1 (main comp
onent) (figure 58). This single S)(C=.0) band was also observed

in other l-monoglycerid.es by Barcelo et al (103).

In this work the Oil) absorption bands are present at

3 292cm“1 and 3238cm*"1 (main component) for MG18, which is a
shift to a lower frequency for the components relative to the

(3* phase of MG 11 signifying a further increase in the H-bcnd
strength upon going to the {3 form. There is also an increase
in intensity and narrowing of b?( Oil) components of the Bform

of MG11 relative to the j2 1 form of MG11.

The *9( C= 0) absorption is resolved as a doublet in the p
forms of all the 1-monoglycerides studied (table IX) . The lower
frequency component in the longer chain 1-monoglycerides (MG11,
MG 12, MG18) is of greater intensity than the other component
whilst in the case of I1G8 the reverse is found, (figure 32). It
therefore appears that the carbonyl may play a much larger role
in the H-bonding scheme of the longer chain compounds than the
shorter ones.

Assignments of the bands was made by comp
aring the MGS spectra with those of long chain saturated alcoh

ols ( 12 , 13 )? n-paraffins (29?242), acids (30, 35) and ethylene

glycol (57)* Further help in the assignment of the bands was
obtained from the spectra of DMG8. The following points arise:-

i. The 3 phase spectrum in figure 33 indicates

that the OH has not been completely replaced by OB, New bonds
at 1025cm”1 and 800cm”1 are assignable to OB in plane vibrations,

$(0D) , corresponding to the bands previously found at 1398cm""1

(1437 cm”1 in ethylene glycol (57)) and 1063cm"’1 in the non-

deuterated compound because the ratios of the frequencies betw

een the two compounds, 1398/1025 ** 1*36 and IO 63 / 8 OO = 1.34

of DMG8 the bands in the vicinity of any residual (3(0H) are
intensified (figure 33) and split into a large number of compon
ents. It is possible that the band at 1403cm"1 is the residual

p(0H) which has shifted to higher frequency due to the low temp
erature and appears more intense because of strong adjacent

bands. Also in the low temperature spectrum of MGS (figure 32)

ii. In the beam temperature spectrum of DMG8 (figure
33) a very broad band, quite weak, a,ppea,rs at approximately

1030cm"1 upon which all the other bands in the region 1200-

950cm"1 are superimposed. This broad band intensifies consider
ably at low temperature (figure 33) whilst remaining in the same
position. Because of this alteration in intensity, bands in this
region of the spectrum are drastically effected. The origin of
this band is not known.

iii. In the low tempere/bure spectrum of MGS there
are at least four .Jf(OH) bands (figure 32) at 633cm"1 , 668cm” 1 ,
775cm”1 and 800cm” 1 and these bands are more intense than the

two weak broad bands observed at 622cm and 642cm”-1 in the beam
temperature spectrum (figure 32). These bands are not observed
in the DMG8 spectra. The increase in frequency and intensity of

&(0H) vibrations with decreasing temperature and resolution into
multiple bands was observed in the case of pinacol (part I,

chapter III). In that case a broad, band at 626cm”1 a„t beam

°C, km/h

°F

°F, Knoten

°C, m/s

°C, km/h

°C, mph

°C, Knoten

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