Environment Effects on the ESR Spectrum of the Cation Radical of Dimethylketene in Low Temperature Matrices

1985 ◽  
Vol 58 (4) ◽  
pp. 1267-1272 ◽  
Author(s):  
Jun Fujisawa ◽  
Shin Sato ◽  
Kazuo Shimokoshi ◽  
Tadamasa Shida
Keyword(s):  
Low Temperature ◽  
Cation Radical ◽  
Esr Spectrum ◽  
Environment Effects

scholarly journals The ESR Spectrum of a π Cation Radical Trapped in a Single Crystal of Chloro(tetraphenylporphyrinato)cobalt(III)

1983 ◽  
Vol 56 (3) ◽  
pp. 822-826 ◽  
Author(s):  
Masahiro Kohno ◽  
Hiroaki Ohya-Nishiguchi ◽  
Kiyoko Yamamoto ◽  
Tosio Sakurai
Keyword(s):  
Single Crystal ◽  
Cation Radical ◽  
Esr Spectrum

Low-temperature ESR spectrum in a powder sample of Cu(C10H8N2)(H2O)2SO4

2004 ◽  
Vol 30 (10) ◽  
pp. 820-821 ◽  
Author(s):  
O. Kravchyna ◽  
A. Kaplienko ◽  
M. Kajnakova
Keyword(s):  
Low Temperature ◽  
Powder Sample ◽  
Esr Spectrum

Triplet ESR spectrum of the copper porphyrin cation radical

1982 ◽  
Vol 104 (7) ◽  
pp. 2057-2059 ◽  
Author(s):  
S. Konishi ◽  
M. Hoshino ◽  
M. Imamura
Keyword(s):  
Cation Radical ◽  
Esr Spectrum ◽  
Copper Porphyrin ◽  
Porphyrin Cation

Low-Temperature Optical and Resonance Raman Spectra of a Carotenoid Cation Radical in Photosystem II

1999 ◽  
Vol 103 (31) ◽  
pp. 6403-6406 ◽  
Author(s):  
John S. Vrettos ◽  
David H. Stewart ◽  
Julio C. de Paula ◽  
Gary W. Brudvig
Keyword(s):  
Low Temperature ◽  
Photosystem Ii ◽  
Raman Spectra ◽  
Resonance Raman ◽  
Cation Radical ◽  
Resonance Raman Spectra

Exsolution and inversion in pigeonite from the Whin Sill, Northern England

1978 ◽  
Vol 36 (1) ◽  
pp. 474-475
Author(s):  
P.P.K. Smith
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Homogeneous Nucleation ◽  
Silicate Mineral ◽  
Antiphase Boundaries ◽  
Two Phase ◽  
Primitive Form ◽  
The Core ◽  
Nucleation Mechanisms ◽  
And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

Low temperature x-ray microanalysis of frozen-hydrated tobacco leaves

1984 ◽  
Vol 42 ◽  
pp. 284-285
Author(s):  
S. Edith Taylor ◽  
Patrick Echlin ◽  
May McKoon ◽  
Thomas L. Hayes
Keyword(s):  
Low Temperature ◽  
Lemna Minor ◽  
Root Tips ◽  
Tobacco Leaves ◽  
X Ray ◽  
Whole Cells ◽  
Carbon Coated ◽  
The Right ◽  
Beam Currents ◽  
The University

Low temperature x-ray microanalysis (LTXM) of solid biological materials has been documented for Lemna minor L. root tips. This discussion will be limited to a demonstration of LTXM for measuring relative elemental distributions of P,S,Cl and K species within whole cells of tobacco leaves.Mature Wisconsin-38 tobacco was grown in the greenhouse at the University of California, Berkeley and picked daily from the mid-stalk position (leaf #9). The tissue was excised from the right of the mid rib and rapidly frozen in liquid nitrogen slush. It was then placed into an Amray biochamber and maintained at 103K. Fracture faces of the tissue were prepared and carbon-coated in the biochamber. The prepared sample was transferred from the biochamber to the Amray 1000A SEM equipped with a cold stage to maintain low temperatures at 103K. Analyses were performed using a tungsten source with accelerating voltages of 17.5 to 20 KV and beam currents from 1-2nA.

Bulk standards for low-temperature biological x-ray microanalysis

1984 ◽  
Vol 42 ◽  
pp. 282-283
Author(s):  
P. Echlin ◽  
M. McKoon ◽  
E.S. Taylor ◽  
C.E. Thomas ◽  
K.L. Maloney ◽  
...  
Keyword(s):  
Phase Separation ◽  
Low Temperature ◽  
Analytical Method ◽  
Salt Solutions ◽  
Absolute Concentration ◽  
Cooling Process ◽  
X Ray ◽  
The Absolute ◽  
Analytical Procedures ◽  
Electrical Conductors

Although sections of frozen salt solutions have been used as standards for x-ray microanalysis, such solutions are less useful when analysed in the bulk form. They are poor thermal and electrical conductors and severe phase separation occurs during the cooling process. Following a suggestion by Whitecross et al we have made up a series of salt solutions containing a small amount of graphite to improve the sample conductivity. In addition, we have incorporated a polymer to ensure the formation of microcrystalline ice and a consequent homogenity of salt dispersion within the frozen matrix. The mixtures have been used to standardize the analytical procedures applied to frozen hydrated bulk specimens based on the peak/background analytical method and to measure the absolute concentration of elements in developing roots.

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