Journal of Magnetic Resonance (1969)最新文献

{"title":"Double DEPT using adiabatic pulses. Indirect heteronuclear T1 measurement with B1 insensitivity","authors":"Seong-Gi Kim, Michael Garwood","doi":"10.1016/0022-2364(92)90224-U","DOIUrl":"10.1016/0022-2364(92)90224-U","url":null,"abstract":"","PeriodicalId":100800,"journal":{"name":"Journal of Magnetic Resonance (1969)","volume":"99 3","pages":"Pages 660-667"},"PeriodicalIF":0.0,"publicationDate":"1992-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-2364(92)90224-U","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85565248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hyperfine sublevel correlation spectroscopy (HYSCORE ) of disordered solids","authors":"J.J Shane, P Höfer , E.J Reijerse, E de Boer","doi":"10.1016/0022-2364(92)90215-S","DOIUrl":"10.1016/0022-2364(92)90215-S","url":null,"abstract":"","PeriodicalId":100800,"journal":{"name":"Journal of Magnetic Resonance (1969)","volume":"99 3","pages":"Pages 596-604"},"PeriodicalIF":0.0,"publicationDate":"1992-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-2364(92)90215-S","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81002818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measuring diffusion in inhomogeneous systems in imaging mode using antisymmetric sensitizing gradients","authors":"Xiaole Hong,&nbsp;W Thomas Dixon","doi":"10.1016/0022-2364(92)90210-X","DOIUrl":"10.1016/0022-2364(92)90210-X","url":null,"abstract":"<div><p>A principle for self-diffusion pulse-sequence design which cancels harmful cross terms involving both imaging and sample susceptibility-induced gradients by using antisymmetric diffusion-sensitizing-gradient pulses is proposed. A water diffusion coefficient of 1.94 × 10⁻⁵ cm² s⁻¹ was obtained by the cross-term-free sequence, a bipolar sensitizing-gradient pulse (BGP) scheme, while the conventional method gave 2.22 and 1.60 × 10⁻⁵ cm² s⁻¹ with sensitizing gradient running parallel and antiparallel to the imaging gradient, respectively. A diffusion coefficient of 1.38 × 10⁻⁵ cm² s⁻¹ was obtained from an apple, in fair agreement with 1.56 × 10⁻⁵ cm² s⁻¹ for its juice, using the BGP sequence. Although the conventional technique gave similar values for apple juice, it gave only about half as large a value for the whole apple, presumably because of internal gradients from inhomogeneous susceptibility. The rms value of these local gradients in the apple was estimated as 6.0 kHz/cm in our 200 MHz instrument.</p></div>","PeriodicalId":100800,"journal":{"name":"Journal of Magnetic Resonance (1969)","volume":"99 3","pages":"Pages 561-570"},"PeriodicalIF":0.0,"publicationDate":"1992-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-2364(92)90210-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79850730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isotopes in the physical and biomedical sciences. vol. 1. labelled compounds (part B)","authors":"W.S.B","doi":"10.1016/0022-2364(92)90228-Y","DOIUrl":"https://doi.org/10.1016/0022-2364(92)90228-Y","url":null,"abstract":"","PeriodicalId":100800,"journal":{"name":"Journal of Magnetic Resonance (1969)","volume":"99 3","pages":"Page 672"},"PeriodicalIF":0.0,"publicationDate":"1992-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-2364(92)90228-Y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136548831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A simple approach to measuring spin diffusion of abundant nuclei in dipolar-broadened solids","authors":"Jianzhi Hu,&nbsp;Chaohui Ye","doi":"10.1016/0022-2364(92)90212-P","DOIUrl":"10.1016/0022-2364(92)90212-P","url":null,"abstract":"","PeriodicalId":100800,"journal":{"name":"Journal of Magnetic Resonance (1969)","volume":"99 3","pages":"Pages 576-581"},"PeriodicalIF":0.0,"publicationDate":"1992-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-2364(92)90212-P","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80574163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimized recording of heteronuclear multidimensional NMR spectra using pulsed field gradients","authors":"Ad Bax ,&nbsp;Susan S Pochapsky","doi":"10.1016/0022-2364(92)90221-R","DOIUrl":"10.1016/0022-2364(92)90221-R","url":null,"abstract":"","PeriodicalId":100800,"journal":{"name":"Journal of Magnetic Resonance (1969)","volume":"99 3","pages":"Pages 638-643"},"PeriodicalIF":0.0,"publicationDate":"1992-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-2364(92)90221-R","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83261940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High pressure NMR","authors":"W.S.B","doi":"10.1016/0022-2364(92)90229-Z","DOIUrl":"https://doi.org/10.1016/0022-2364(92)90229-Z","url":null,"abstract":"","PeriodicalId":100800,"journal":{"name":"Journal of Magnetic Resonance (1969)","volume":"99 3","pages":"Pages 672-673"},"PeriodicalIF":0.0,"publicationDate":"1992-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-2364(92)90229-Z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136548829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ingress of water into solid nylon 6.6","authors":"P Mansfield,&nbsp;R Bowtell,&nbsp;S Blackband","doi":"10.1016/0022-2364(92)90206-M","DOIUrl":"https://doi.org/10.1016/0022-2364(92)90206-M","url":null,"abstract":"<div><p>The ingress of water into Nylon 6.6 has been studied over a range of temperatures by nuclear magnetic resonance imaging techniques. The results have been used to extract the translational diffusion coefficient as a function of water concentration for various temperatures. These results in turn allow the activation energies to be evaluated. Other experiments have been made to measure the spin relaxation times <em>T</em>₁ and <em>T</em>₂. The results are interpreted using a two-phase exchange model from which good agreement for both the diffusion and relaxation-time data is obtained. High-pressure diffusion results also presented support the view that water is taken up preferentially at the amorphous amide sites in the Nylon and that pressure increases serve to force water onto sitccupied sites and/or onto occupied sites, giving up to three waters per amide site.</p></div>","PeriodicalId":100800,"journal":{"name":"Journal of Magnetic Resonance (1969)","volume":"99 3","pages":"Pages 507-524"},"PeriodicalIF":0.0,"publicationDate":"1992-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-2364(92)90206-M","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72241697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of scalar coupling constants by inverse Fourier transformation of in-phase multiplets","authors":"T Szyperski,&nbsp;P Güntert,&nbsp;G Otting,&nbsp;K Wüthrich","doi":"10.1016/0022-2364(92)90209-P","DOIUrl":"10.1016/0022-2364(92)90209-P","url":null,"abstract":"<div><p>A generally applicable new method for the determination of scalar coupling constants for spins with a single coupling partner, in particular ³<em>J</em>_{HN<em>α</em>}. in polypeptides, is described. It has the special advantage for use in protein structure determinations that no extra NMR experiments need to be recorded, and that NOE distance constraints and dihedral angle constraints from ³<em>J</em>_{HN<em>α</em>} can be derived from the same data sets. The scalar coupling constants are extracted from the in-phase multiplets of homonuclear [¹H, ¹H] NOESY spectra or heteronuclear [¹⁵N, ¹H ] COSY spectra through inverse Fourier transformation of the data points representing a cross peak along <em>ω</em>₂, and a subsequent nonlinear least-squares fit in the time domain. Practical applications are described for recombinant hirudin and the basic pancreatic trypsin inhibitor.</p></div>","PeriodicalId":100800,"journal":{"name":"Journal of Magnetic Resonance (1969)","volume":"99 3","pages":"Pages 552-560"},"PeriodicalIF":0.0,"publicationDate":"1992-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-2364(92)90209-P","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72387336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The 9 and 33 GHz EPR Spectra of Mn2+ impurity ions in polycrystalline calcite—Central transition","authors":"Y.P Zhang,&nbsp;H.A Buckmaster","doi":"10.1016/0022-2364(92)90208-O","DOIUrl":"10.1016/0022-2364(92)90208-O","url":null,"abstract":"<div><p>The 293 K EPR spectra of Mn²⁺ impurity ions in polycrystalline natural and synthetic calcite and in the calcite impurity in various coal samples have been studied at 9.2 and 33.3 GHz. The spectra obtained at these two frequencies were found to differ dramatically. At 9.2 GHz, the lineshapes of the central transition hyperfine resonances are in good agreement with previous measurements. The 33.3 GHz EPR spectrum has some features which have not been reported previously at Mn²⁺ concentrations below 1000 ppm. Computer simulation programs for both spin-Hamiltonian perturbation and diagonalization techniques were used to describe the mono- and polycrystalline spectra. It was found that the simulated spectrum using the spin-Hamiltonian diagonalization method agrees with previous 9.3 GHz monocrystal data within an error of 0.1 mT for the central transitions and of 0.13 mT for the noncentral transitions, whereas the simulation using the perturbation method had errors of 0.2 and 0.6 mT, respectively. An analysis of the polycrystalline hyperfine resonance lineshapes observed at 9.2 and 33.3 GHz for 1, 50, and 520 ppm Mn²⁺ concentrations has been performed using both simulation methods. The hyperfine resonance lineshapes observed at 9.2 GHz are due to the magnetic field angular variation caused by the axial zero field splitting (ZFS) term <em>C</em>₀²(<em>S</em>). The hyperfine resonance lineshapes observed at 33.3 GHz are shown to be due to the combined effect of A-tensor and g-tensor anisotropy, the axial ZFS, and the spin-spin interaction. The Mn²⁺ impurity ion EPR spectrum observed in an Alberta coal and several Argonne coal samples is shown, using lineshape analysis, to originate from their calcite mineral impurity. The lineshape broadening observed in coal samples is characteristic of a strong spin-spin interaction and may be due to interactions with the free radicals and other impurity ions as well as between Mn²⁺ ions.</p></div>","PeriodicalId":100800,"journal":{"name":"Journal of Magnetic Resonance (1969)","volume":"99 3","pages":"Pages 533-551"},"PeriodicalIF":0.0,"publicationDate":"1992-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0022-2364(92)90208-O","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88507243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}