Spectroscopic analysis (IR, Raman and 1H NMR) of low molecular weight organic fraction extracted from soil

1999 ◽  
pp. 587-588
Author(s):  
O. Francioso ◽  
S. Sánchez-Cortés ◽  
C. Ciavatta ◽  
C. Marzadori ◽  
J. V. García-Ramos ◽  
...  
Keyword(s):  
Molecular Weight ◽  
1H Nmr ◽  
Spectroscopic Analysis ◽  
Low Molecular Weight ◽  
Organic Fraction

Study of oligomers and low molecular weight polycarbonate fractions by 13C and 1H NMR spectroscopy

1980 ◽  
Vol 22 (4) ◽  
pp. 1027-1037 ◽  
Author(s):  
Ya.G. Urman ◽  
S.G. Alekseyeva ◽  
V.V. Amerik ◽  
A.G. Balabushevich ◽  
B.M. Arshava ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Nmr Spectroscopy ◽  
1H Nmr ◽  
1H Nmr Spectroscopy ◽  
Low Molecular Weight

Molecular Dynamics in a New Solid Glucofuranose-Based Low-Molecular-Weight Organogelator as Studied by 1H NMR

2008 ◽  
Vol 33 (4) ◽  
pp. 431-438 ◽  
Author(s):  
M. Bielejewski ◽  
A. Rachocki ◽  
R. Luboradzki ◽  
J. Tritt-Goc
Keyword(s):  
Molecular Dynamics ◽  
Molecular Weight ◽  
1H Nmr ◽  
Low Molecular Weight

Chain Extension of Poly(butylene adipate) with 2,2’-(1,4- Phenylene)-bis(2-oxazoline)

2006 ◽  
Vol 11-12 ◽  
pp. 387-390 ◽  
Author(s):  
Si Yang Luo ◽  
Yu Zhang ◽  
Jing Bo Zhao
Keyword(s):  
Molecular Weight ◽  
Influencing Factors ◽  
1H Nmr ◽  
Reaction Temperature ◽  
Chain Extender ◽  
Chain Extension ◽  
Molar Ratio ◽  
Low Molecular Weight ◽  
Melt Polycondensation

Low molecular weight poly(butylene adipate) (PBA) was synthesized by melt polycondensation. The chain extension of the prepolymers was carried out using 2,2’-(1,4-phenylene)-bis(2-oxazoline) (PBOX) as chain-extender. The influencing factors including reaction temperature, oxazoline/-COOH molar ratio, and the molecular weight of prepolymers were studied. At the optimal chain-extending condition, PBA with Mn of 38583 and Mw of 125497 was prepared. The structure of the chain-extended PBA was also characterized by the FTIR and 1H NMR.

Sulfur Vulcanization of Simple Model Olefins, Part I: Characterization of Vulcanization Products of 2,3-Dimethyl-2-Butene

1992 ◽  
Vol 65 (2) ◽  
pp. 343-349 ◽  
Author(s):  
P. Versloot ◽  
J. G. Haasnoot ◽  
J. Reedijk ◽  
M. van Duin ◽  
E. F. J. Duynstee ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Double Bond ◽  
Simple Model ◽  
1H Nmr ◽  
Low Molecular Weight ◽  
Rp Hplc ◽  
Sulfur Vulcanization ◽  
Weight Model

Abstract To study the mechanism of the sulfur vulcanization of rubber, 2,3-dimethyl-2-butene (C6H12) was used as a simple, low-molecular-weight model alkene. Only equivalent allylic positions are present in this alkene. Treating C6H12 with a mixture of ZnO, S8, and the accelerator tetramethylthiuramdisulfide at 140°C yields a mixture of addition products (C6H11—Sn—C6H11). RP-HPLC in combination with MS and 1H-NMR shows that the products differ only in the length of the sulfur bridge. Small quantities of isomerized products have been found, in which a 1,3-shift of the double bond has occurred.

1H-NMR-based water-soluble low molecular weight compound characterization and free fatty acid composition of five kinds of Yunnan dry-cured hams

LWT ◽  
2019 ◽  
Vol 108 ◽  
pp. 174-182 ◽  
Author(s):  
Shuyun Liu ◽  
Guiying Wang ◽  
Zhichao Xiao ◽  
Yuehong Pu ◽  
Changrong Ge ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Acid Composition ◽  
1H Nmr ◽  
Water Soluble ◽  
Low Molecular Weight

Improved quality of 1H NMR spectroscopic data for enhanced metabolic profiling of low molecular weight metabolites in human serum

Metabolomics ◽  
2010 ◽  
Vol 7 (2) ◽  
pp. 270-277 ◽  
Author(s):  
Svenja Stolzenburg ◽  
Michael B. Lauridsen ◽  
Henrik Toft ◽  
Pierre A. Zalloua ◽  
Dorrit Baunsgaard
Keyword(s):  
Molecular Weight ◽  
Human Serum ◽  
1H Nmr ◽  
Metabolic Profiling ◽  
Spectroscopic Data ◽  
Low Molecular Weight

scholarly journals RESEARCH OF THE COMPOSITION OF PRODUCTS OF MICROWAVE PYROLYSIS OF WOOD

2021 ◽  
pp. 32-36
Author(s):  
O. I. Tuzhikov ◽  
T. V. Khokhlova ◽  
S. A. Orlova ◽  
O. O. Tuzhikov
Keyword(s):  
Molecular Weight ◽  
Spectroscopic Analysis ◽  
Liquid Fraction ◽  
Raw Material ◽  
Gas Mixture ◽  
Low Molecular Weight ◽  
Pyrolysis Process ◽  
Microwave Pyrolysis ◽  
Microwave Action ◽  
Composition Of Products

A method of microwave action on wood of various species was developed, as a result of which the pyrolysis process was carried out. Allocated solid, gaseous fractions, as well as as a result of condensation of a vapor-gas mixture, pyrolysate, which is a raw material for the production of low molecular weight organic compounds of various classes. Gas chromatography-mass spectroscopic analysis of the liquid fraction was carried out, the components included in its composition were identified. The proposed method allows liquefaction of wood for 20-30 minutes in the temperature range from 230 to 423 °С.

A high-performance oil-free backing pump for electron microscopes

1978 ◽  
Vol 36 (1) ◽  
pp. 110-111
Author(s):  
G.K.W. Balkau ◽  
E. Bez ◽  
J.L. Farrant
Keyword(s):  
Molecular Weight ◽  
Electron Microscope ◽  
Hot Spots ◽  
High Performance ◽  
Carbonaceous Material ◽  
Contamination Rate ◽  
Low Molecular Weight ◽  
Principal Source ◽  
Rotary Pumps ◽  
Electron Microscopes

The earliest account of the contamination of electron microscope specimens by the deposition of carbonaceous material during electron irradiation was published in 1947 by Watson who was then working in Canada. It was soon established that this carbonaceous material is formed from organic vapours, and it is now recognized that the principal source is the oil-sealed rotary pumps which provide the backing vacuum. It has been shown that the organic vapours consist of low molecular weight fragments of oil molecules which have been degraded at hot spots produced by friction between the vanes and the surfaces on which they slide. As satisfactory oil-free pumps are unavailable, it is standard electron microscope practice to reduce the partial pressure of organic vapours in the microscope in the vicinity of the specimen by using liquid-nitrogen cooled anti-contamination devices. Traps of this type are sufficient to reduce the contamination rate to about 0.1 Å per min, which is tolerable for many investigations.

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