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Communiols E-H: New polyketide metabolites from the coprophilous fungus Podospora communis
(2005-03-01)
Communiols E-H (1-4), four new polyketide-derived natural products containing furanocyclopentane, furanocyclopentene, cyclopentene, or γ-lactone moieties, have been isolated from two geographically distinct isolates of the ...
Electric and magnetic properties of polymer electrolyte/carbon black composites
(1998-12-01)
Measurements of 1H Nuclear Magnetic Resonance (NMR) relaxation times, Electron Paramagnetic Resonance (EPR) and AC Impedance Spectroscopy (IS) are reported for composites based on PEO8:LiClO4 and carbon black (CB), prepared ...
Bioactive guanidine alkaloids from Pterogyne nitens
(1995-12-01)
Bioactivity-guided fractionation of a methanolic CHCl 3 extract of the leaves of Pterogyne nitens afforded the known guanidine alkaloid pterogynidine [2] and three new guanidine alkaloids, nitensidines A [3], B [4], and C ...
Use of on-line liquid chromatography-nuclear magnetic resonance spectroscopy for the rapid investigation of flavonoids from Sorocea bomplandii
(Elsevier B.V., 2002-04-12)
This paper reports the identification of di- and triglycosylated flavonoids from Sorocea bomplandii (Moraceae) by liquid chromatography coupled on-line to nuclear magnetic resonance (LC-NMR). These glycosylated flavonoids ...
Carbon nuclear magnetic resonance spectroscopic fingerprinting of commercial gasoline: Pattern-recognition analyses for screening quality control purposes
(Elsevier B.V., 2010-06-30)
In this work, the combination of carbon nuclear magnetic resonance ((13)C NMR) fingerprinting with pattern-recognition analyses provides an original and alternative approach to screening commercial gasoline quality. Soft ...
Magnetic resonance study of the crystallization behavior of InF3-based glasses doped with Cu2+, Mn2+ and Gd3+
(2006-09-15)
The crystallization of fluoroindate glasses doped with Gd3+, Mn2+ and Cu2+ heat treated at different temperatures, ranging from the glass transition temperature (Tg) to the crystallization temperature (Tc), are investigated ...
Nuclear magnetic relaxation for the spin-degenerate Anderson model
(Elsevier B.V., 2014)
Thermal decomposition of acetylsalicylic acid (aspirin)
(1996-06-01)
The thermal decomposition of aspirin in air and dry air flux was investigated. Thermogravimetry-derivative thermogravimetry (TG-DTG), differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), infrared ...
Thermal Behavior and Spectroscopic Study of Neutral and Cationic Mononuclear Cyclopalladated Compounds
(2003-11-25)
The reactions of the precursor [Pd(N,C-dmba)(MeCN)2](NO 3) (1) (dmba = N,N-dimethylbenzylamine), with the proligands 3,5-dimethylpyrazole (Hdmpz), 2-quinolinethiol (qnSH) and 1,1′- bis(diphenylphosphine)ferrocene (dppf) ...
Pilomyxoid astrocytoma of the brainstem
(2013-04-15)
A pilomyxoid astrocytoma is a recently described tumor that occurs predominantly in the hypothalamic-chiasmatic region and is rarely found elsewhere. It has similar features as pilocytic astrocytomas, but has distinct ...