نتایج جستجو برای: nmr spectra
تعداد نتایج: 160021 فیلتر نتایج به سال:
Trifluormethylazosulfon-N,N-dimethylamid, Vibrational Spectra, NMR Spectra, Mass Spectra, Crystal Structure The reaction of Trifluoronitrosomethan with (CH3)2NS(0 )2NH2 in THF and Na2C 0 3 as base give the yellow liquid (CH3)2NS(0 )2NNCF3. The new compound melts at 283 K and were characterized by vibrational, NMR and mass spectra. In addition, the crystal structure of (CH3)2NS(0 )2NNCF3 has bee...
NMR spectroscopy is the go-to technique for determining the solution structures of organic, organometallic, and even macromolecular species. However, structure determination of nanoscale aqueous inorganic clusters by NMR spectroscopy remains an unexplored territory. The few hydroxobridged inorganic species well characterized by H Nuclear Magnetic Resonance spectroscopy (H-NMR) do not provide en...
UNLABELLED NMR chemical shift perturbation experiments are widely used to define binding sites in biomolecular complexes. Especially in the case of high throughput screening of ligands, rapid analysis of NMR spectra is essential. NvMap extends NMRViewJ and provides a means for rapid assignments and book-keeping of NMR titration spectra. Our module offers options to analyze multiple titration sp...
SUMMARY We present here the freely available Metabolomics Project resource specifically designed to work under the CcpNmr Analysis program produced by CCPN (Collaborative Computing Project for NMR) (Vranken et al., 2005, The CCPN data model for NMR spectroscopy: development of a software pipeline. Proteins, 59, 687-696). The project consists of a database of assigned 1D and 2D spectra of many c...
High-resolution NMR spectra under inhomogeneous fields via intermolecular double-quantum coherences.
High-resolution NMR spectroscopy is a powerful tool for analyzing molecular structures and compositions. Line-widths of conventional liquid NMR signals are directly proportional to the overall magnetic field inhomogeneity the sample experiences. In many circumstances, spatial and temporal homogeneity of the magnetic field is degraded. In this paper, a modified pulse sequence based on intermolec...
NMR analysis is a complex topic, from both the spectral interpretation and fundamental physics points of view. This section supplements the text on both of these fronts by first providing a concise summary of important general material, followed by the background necessary to interpret H-NMR spectra for molecules that have more complex signal splitting patterns. We assume that you are already f...
Semiochemicals are often produced in infinitesimally small quantities, so their isolation requires large amounts of starting material, not only requiring significant effort in sample preparation, but also resulting in a complex mixture of compounds from which the bioactive compound needs to be purified and identified. Often, compounds cannot be unambiguously identified by their mass spectra alo...
2H Magic-angle spinning nuclear magnetic resonance (MAS NMR), echo 27Al NMR, two-dimensional (2D) echo 1H MAS NMR and 1H, 27Al and 29Si MAS NMR have been applied to study the acid sites of dehydrated zeolites. The quadrupole coupling constants CQCC determined from 2H MAS NMR spectra of Si-OH-Al sites increase with the framework aluminium content of the zeolites from 208 Hz (H-ZSM-5) to 236 kHz ...
Proton nuclear magnetic resonance ((1)H NMR) spectra of leaves from 50 plant species were obtained at a spectrometer frequency of 470 MHz. Water present in leaf samples gives rise to characteristic spectral patterns. Most species show only one broad (1)H NMR peak; however, the leaves of some plants display complex, orientation-dependent spectra in which a common three-line pattern is discerned....
In the structural analysis of lignins by 13C-NMR, signal overlap limits definitive assignment and accurate inten sity measurement. Selective labeling by 13C-enrichment of a specific carbon in lignin enhances its signal intensity in the spectrum. Further enhancement of the specifically labeled carbons can be realized via difference spectra created from the enriched and unenriched samples. Diffe...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید