Results 221 to 230 of about 66,931 (265)

IR and/or NMR Spectra-Structure Correlations for Organonitrogen-Containing Compounds

Applied Spectroscopy, 1988
IR and/or NMR spectra-structure correlations have been developed which aid in the elucidation of molecular structure of organonitrogen-containing compounds.
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Spectroscopic studies on soil organic fractions i. ir and nmr spectra

Soil Biology and Biochemistry, 1977
Abstract A study has been made using i.r. and n.m.r. spectroscopic techniques to investigate ten different organic fractions extracted in a series of mild organic solvents from a brown soil from Sardinia. The experimental results gave useful information about the nature of the extracted samples, which differ considerably from one another. Some of the
O. Sciacovelli, N. Senesi, V. Solinas, C. Testini   +3 more
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NMR, IR and Raman spectra study of the structure of borate and borosilicate glasses

Journal of Non-Crystalline Solids, 1989
Abstract Comparative studies on the IR and NMR of some binary borate systems and ternary borosilicate systems were made. The results of NMR in R 2 OB 2 O 3 , La 2 O 3 B 2 O 3 and Na 2 OB 2 O 3 SiO 2 glass systems were measured and calculated using the phase diagram model.
Tang Yongxing, Jiang Zhonghong, Song Xiuyu   +2 more
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The13C NMR, UV and IR spectra of 2-fluoropyridine methyl derivatives

Chemistry of Heterocyclic Compounds, 1999
13C NMR, UV, and IR spectra of methyl derivatives of 2-fluoropyridine have been recorded. The influence of the substituents on the spectral characteristics of the compounds has been discussed. The electronic spectra have been calculated by a modified INDO method. Transition energies, intensities, and assignments are compared with UV spectra.
A. Puszko, H. Ciurla
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Analysis of NMR and FT-IR spectra on the bis(substituted cyclopentadienyl)dichlorides of titanium and zirconium

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2008
The NMR and FT-IR spectra of 10 (etaC6H9CRR'-Cp)2MCl2 (M=Ti, Zr) were measured. Results indicate that the metal atom formed bond combination with the center of cyclopentadienyl. NMR spectra move to high field when electronegativity decreases. The electronegativity difference of Ti and Zr mainly influences their IR spectra at the far-infrared range. The
Jianbo, Zhang, Zhenqiang, Xu, Yueru, Zong, Zhenhua, Xu, Shoushan, Chen   +4 more
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E-Homolupane Derivatives Substituted in Position 17 and 22a. 1H NMR, 13C NMR and IR Spectra

Collection of Czechoslovak Chemical Communications, 1995
A series of derivatives with various oxygen functionalities in positions 17,22a or 19,20 was prepared from diene I and olefin XVI by addition and oxidation reactions. The structure of the obtained compounds was confirmed by 1H NMR, 13C NMR and IR spectroscopy.
Václav Křeček, Stanislav Hilgard, Miloš Buděšínský, Alois Vystrčil   +3 more
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13C NMR, 1H NMR and IR spectra of a series of monochloroesters of aliphatic short chain carboxylic acids

Tetrahedron, 1981
Abstract 13 C chemical shifts for 14 isomeric monochloroesters of aliphatic carboxylic acids from propanoic acid to hexanoic acid have been determined. Comparisons are made with the literature values for methyl monochloro-octanoate isomers. Substituent effects for all positions are given.
Maija T. Pitkänen, Ilpo O.O. Korhonen, Jorma N.J. Korvola   +2 more
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NMR and IR spectra-structure correlations for carbonyl containing compounds in various solvents

Journal of Molecular Structure, 1996
Abstract The δ 13 CO chemical shifts and the carbonyl stretching frequencies ν CO are affected by their physical surroundings, and information about the chemical structure can be obtained by study of δ 13 CO and ν CO in various solvents or solvent systems.
R.A. Nyquist, R. Streck, G. Jeschek
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Multimodal Machine Learning for Molecular Identification Based on IR, Raman, and NMR Spectra

The Journal of Physical Chemistry Letters
Accurate molecular structure recognition is vital in chemistry and drug discovery, yet single-spectrum methods often struggle with limited accuracy and robustness. Here, we present a multimodal machine learning framework based on our previously developed TranSpec to integrate IR, Raman, and NMR spectra for precise structure prediction.
Sheng Wu, Shengjiao Ji, Mingzhi Yuan, Jun Jiang, Yi Luo, Wei Hu   +5 more
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Coordination Properties of Magnesium in Chlorophyll from IR and NMR Spectra

1968
The infrared (IR) and nuclear magnetic resonance (NMR) spectra of chlorophyll are best interpreted on the basis that the central magnesium atom of the chlorophyll always has a coordination number larger than 4. In electron-donor solvents, chlorophyll exists as monomer, with solvent molecules filling the axial position(s).
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