Relevant bibliographies by topics / J-couplings

Academic literature on the topic 'J-couplings'

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Published: 6 September 2023

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Journal articles on the topic "J-couplings"

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Gleeson, Ronan, Cecilie L. Andersen, Peter Rapta, Peter Machata, Jørn B. Christensen, Ole Hammerich, and Stephan P. A. Sauer. "A Combined Experimental and Theoretical Study of ESR Hyperfine Coupling Constants for N,N,N’,N’-Tetrasubstituted p-Phenylenediamine Radical Cations." International Journal of Molecular Sciences 24, no. 4 (February 8, 2023): 3447. http://dx.doi.org/10.3390/ijms24043447.

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A test set of N,N,N’,N’-tetrasubstituted p-phenylenediamines are experimentally explored using ESR (electron spin resonance) spectroscopy and analysed from a computational standpoint thereafter. This computational study aims to further aid structural characterisation by comparing experimental ESR hyperfine coupling constants (hfccs) with computed values calculated using ESR-optimised “J-style” basis sets (6-31G(d,p)-J, 6-31G(d,p)-J, 6-311++G(d,p)-J, pcJ-1, pcJ-2 and cc-pVTZ-J) and hybrid-DFT functionals (B3LYP, PBE0, TPSSh, ωB97XD) as well as MP2. PBE0/6-31g(d,p)-J with a polarised continuum solvation model (PCM) correlated best with the experiment, giving an R2 value of 0.8926. A total of 98% of couplings were deemed satisfactory, with five couplings observed as outlier results, thus degrading correlation values significantly. A higher-level electronic structure method, namely MP2, was sought to improve outlier couplings, but only a minority of couples showed improvement, whilst the remaining majority of couplings were negatively degraded.
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MATHEUS, R. D., F. S. NAVARRA, M. NIELSEN, and R. RODRIGUES DA SILVA. "J/ψ COUPLINGS TO OPEN CHARM MESONS FROM QCD SUM RULES." International Journal of Modern Physics E 14, no. 04 (June 2005): 555–67. http://dx.doi.org/10.1142/s0218301305003399.

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We employ QCD sum rules to calculate the J/ψ form factors and coupling constants with charmed mesons, by studying three-point correlation functions. In particular, we consider the J/ψD*D and J/ψDD vertices. We determine the momentum dependence of the form factors for kinematical conditions where J/ψ, D or D* are off-shell. Extrapolating to the pole of each of the form factors obtained, we determine the coupling constants. For both couplings, our results (within the errors) are compatible with estimates based on the constituent quark model.
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Kessler, H., D. F. Mierke, and T. Huber. "At last: J-couplings again." Journal of Molecular Graphics 11, no. 4 (December 1993): 263. http://dx.doi.org/10.1016/0263-7855(93)80018-m.

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Buevich, Alexei V., Josep Saurí, Teodor Parella, Nunziatina De Tommasi, Giuseppe Bifulco, R. Thomas Williamson, and Gary E. Martin. "Enhancing the utility of 1JCH coupling constants in structural studies through optimized DFT analysis." Chemical Communications 55, no. 41 (2019): 5781–84. http://dx.doi.org/10.1039/c9cc02469g.

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High accuracy for DFT-predicted 1JCH-couplings can be achieved without ad hoc corrections or empirical scaling by careful selection of the DFT method utilized for geometry optimization and J-coupling calculations.
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Laporta, V., F. Piccinini, A. D. Polosa, and V. Riquer. "J/ψ strong couplings to vector mesons." European Physical Journal C 48, no. 2 (October 24, 2006): 545–51. http://dx.doi.org/10.1140/epjc/s10052-006-0075-8.

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ROSNER, H., R. R. P. SINGH, W. E. PICKETT, W. H. ZHENG, and J. OITMAA. "ELECTRONIC STRUCTURE AND EXCHANGE IN Li2VOSiO4." International Journal of Modern Physics B 16, no. 11n12 (May 20, 2002): 1649–53. http://dx.doi.org/10.1142/s0217979202011111.

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Exchange couplings are calculated for Li2VOSiO4 using local density approximation (LDA). From a two band tight-binding model fitted to the LDA band structure and mapped to a Heisenberg model, the in-plane and inter-plane exchange integrals are obtained. While the sum of in-plane couplings J1+J2=9.5±1.5 K and the inter-plane coupling J⊥ ~ 0.2-0.3 K agree with recent experimental data, the ratio J2/J1 ~ 12 exceeds the reported value by an order of magnitude. Using geometrical considerations, high temperature expansions and perturbative mean field theory, we show that the LDA derived exchange constants lead to a remarkably accurate description of the properties of these materials including specific heat, susceptibility and Neél temperatures.
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Delaglio, Frank, Dennis A. Torchia, and Ad Bax. "Measurement of15N-13C J couplings in staphylococcal nuclease." Journal of Biomolecular NMR 1, no. 4 (November 1991): 439–46. http://dx.doi.org/10.1007/bf02192865.

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Farley, Kathleen A., Ye Che, Armando Navarro-Vázquez, Chris Limberakis, Dennis Anderson, Jiangli Yan, Michael Shapiro, Veerabahu Shanmugasundaram, and Roberto R. Gil. "Cyclic Peptide Design Guided by Residual Dipolar Couplings, J-Couplings, and Intramolecular Hydrogen Bond Analysis." Journal of Organic Chemistry 84, no. 8 (January 3, 2019): 4803–13. http://dx.doi.org/10.1021/acs.joc.8b02811.

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FASSOULIOTIS, DIMITRIS. "CHARGED TGC FROM 1999 DELPHI DATA." International Journal of Modern Physics A 16, supp01a (October 2001): 299–301. http://dx.doi.org/10.1142/s0217751x01006747.

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Measurements of the trilinear gauge boson couplings WWγ and WWZ are presented from data taken by DELPHI in 1999 at an energy ranging from 192 to 202 GeV. Values are extracted with respect to [Formula: see text] and Δ κγ, the differences of the WWZ charge coupling and of the WWγ dipole coupling from their Standard Model values, and λγ, the WWγ quadrupole coupling. The study uses data from the final states jjℓν, jjjj, ℓX, jjX and γX, where j represents a quark jet, l an identified lepton and X missing four-momentum. The observations are consistent with the Standard Model predictions.
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Rusakov, Yury Yu, Leonid B. Krivdin, Natalia V. Istomina, Ekaterina P. Levanova, and Galina G. Levkovskaya. "Conformational Analysis of 2-Formylselenophene by Means of 13C - 1H, 13C - 13C, and 77Se - 1H Spin - Spin Coupling Constants." Australian Journal of Chemistry 62, no. 7 (2009): 734. http://dx.doi.org/10.1071/ch09010.

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Theoretical energy-based conformational analysis of 2-formylselenophene performed at the MP2/6–311G** level together with experimental measurements and SOPPA/aug-cc-pVTZ-J calculations of its 13C–1H, 13C–13C, and 77Se–1H spin–spin coupling constants showed that this compound predominantly adopts the s-cis conformation. Most of the spin–spin coupling constants under study, especially vicinal 77Se–1H couplings, demonstrate remarkable stereochemical behaviour with respect to the internal rotation of the formyl group, which is of major importance in stereochemical studies of the related selenium-containing compounds.
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Dissertations / Theses on the topic "J-couplings"

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Sanz, Camacho Paula. "Synthetic, spectroscopic and structural studies of chalcogen peri-substituted heterocycles : a solid-state NMR perspective." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/15854.

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Chalcogen-containing materials are an area of increasing interest for spintronic applications. The synthesis, structures and reactivity of these novel compounds are normally studied by solution-state nuclear magnetic resonance (NMR) spectroscopy, density functional theory (DFT) calculations and single-crystal X-ray diffraction. In this thesis, a range of chalcogen-containing heterocycles has been explored, focussing on the solid-state nature and exploring the bulk samples. Therefore, all materials were studied by powder X-ray diffraction and solid-state NMR, in addition to conventional solution-state NMR and single-crystal X-ray diffraction. DFT calculations were also used to interpret the solid-state NMR spectra and to gain insight into the NMR parameters. In the first chapter of results, a series of mixed Te, Se acenaphthenes is investigated. 77Se and 125Te NMR parameters are explored to determine whether changes in the Te aryl-group have an impact on the local environments of both nuclei. Dynamics and the requirement to consider relativistic effects for calculations of NMR parameters of heavy atoms is discussed. In the second results chapter, a series of novel P-S and P-Se six-membered heterocycles are described in terms of their synthesis, reactivity, and 31P and 77Se local environments. We observed and measured some unusual “through-space” couplings that occur between molecules and which mechanism and pathways are supported by DFT calculations. In the third results chapter, these heterocycles are oxidised with O, S and Se and the NMR parameters are discussed in terms of the structure. Polymorphism, phase transitions and weak interactions are some of the phenomena present in these novel compounds. This thesis demonstrated that solid-state NMR is a very good probe to study Se- and Te-containing materials.
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Green, Timothy Frederick Goldie. "Prediction of NMR J-coupling in condensed matter." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:39ee4a7c-58f9-49fa-b14c-16bc03141e53.

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Nuclear magnetic resonance (NMR) is a popular spectroscopic method and has widespread use in many fields. Recent developments in solid-state NMR have increased interest in experiment and, alongside simultaneous developments in computational theory, have led to the field dubbed 'NMR crystallography.' This is a suite of methodologies, complementing the capabilities of other crystallographic methods in the determination of atomic structure, especially when large crystals cannot be made and when exploring materials with phenomena such as compositional, positional and dynamic disorder. NMR J-coupling is the indirect coupling between nuclear spins, which, when measured, can reveal a wealth of information about structure and bonding. This thesis develops and applies the method of Joyce for the prediction of NMR J-coupling in condensed matter systems using plane-wave pseudopotential density-functional theory, an important requirement for efficient treatment of finite and infinite periodic systems. It describes the first-ever method for the use of ultrasoft pseudopotentials and inclusion of special relativistic effects in J-coupling prediction, allowing for the treatment of a wider range of materials systems and overall greater user friendliness, thus making the method more accessible and attractive to the wider scientific community.
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Joyce, Siân Ann. "First principles prediction of nuclear magnetic resonance J-coupling." Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614709.

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Wigglesworth, Richard D. "The calculation of nuclear shielding and spin-spin coupling constants in the water and acetylene molecules." Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301581.

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Welderufael, Zenawi Teklay. "J-coupling predictor function building and large-scale NMR simulations of proteins and nucleic acids." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/409733/.

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This thesis discusses large scale quantum mechanical NMR simulations and fitting works, and deals with biomolecular spin systems. Chapter one introduces the theoretical background that underpins the simulation work. It describes spin and it properties, the interactions of spin with the magnetic field, the environment and it self and the Hamiltonians that describe those interactions. It also covers the Bloch equations that is normally used to predict the longitudinal and transverse relaxations. It further briefly describes the common relaxation mechanisms that are available for a spin system. It also included NMR experiments that are often used in the study of protein and nucleic acid systems. Chapter 2 summarizes the building of J-coupling predictor function. It provides the detail on how the estimator function was built. The function is required for NMR simulations and incorporates the functionality of J-coupling estimation, which provides J-coupling values for proteins and nucleic acids. After building the estimator function NOESY spectra simulation of ubiquitin and RNA stem loops spin systems was performed. Chapter 3 then discusses our simulation method, treating the system quantum mechanically along with an advanced and detailed description of NOE using Redfield relaxation theory. Chapter 4 reports on large–scale simulations and fitting of an exchanging 1H-15N HSQC spectra of calmodulin (PDB: 1CLL) upon stepwise addition of a ligand, that was analysed using a iii formalism that operates in the direct product of spin state space and chemical state space. It also presents the least squares technique for the fitting procedure and the Nelder-Mead simplex minimization technique used in the process. The chapter also highlights the data collated from the fitting work. Finally, chapter 5 concludes the thesis with the simulation of NOESY stem loops RNA spin system and fitting with respect to correlation time and frequency offset. It also explains how we fitted the data from theory to those from the experiment and why the diagonal peaks were eliminated from the fitting.
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Baust, Alexander Theodor [Verfasser], Rudolf [Akademischer Betreuer] Gross, and Jonathan J. [Akademischer Betreuer] Finley. "Tunable Coupling and Ultrastrong Interaction in Circuit Quantum Electrodynamics / Alexander Theodor Baust. Gutachter: Rudolf Gross ; Jonathan J. Finley. Betreuer: Rudolf Gross." München : Universitätsbibliothek der TU München, 2015. http://d-nb.info/1072758237/34.

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Baust, Alexander Theodor Verfasser], Rudolf [Akademischer Betreuer] [Gross, and Jonathan J. [Akademischer Betreuer] Finley. "Tunable Coupling and Ultrastrong Interaction in Circuit Quantum Electrodynamics / Alexander Theodor Baust. Gutachter: Rudolf Gross ; Jonathan J. Finley. Betreuer: Rudolf Gross." München : Universitätsbibliothek der TU München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:91-diss-20150611-1252065-1-0.

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Smith, Fiona Elizabeth. "Observation of the infrared spectrum of the doubly charged molecular ion D'3'7Cl'2'+." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323488.

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Bollero, Real Alberto. "Isotropic nanocrystalline (Nd,Pr)(Fe,Co)B permanent magnets." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2003. http://nbn-resolving.de/urn:nbn:de:swb:14-1069758225796-19366.

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Nanokristalline Permanentmagnete zeigen ungewöhnliche magnetische Eigenschaften aufgrund von Oberflächen- und Grenzflächeneffekten, die verschieden von denen massiver oder mikrokristalliner Materialien sind. Diese Arbeit zeigt Ergebnisse einer systematischen Untersuchung der Beziehung zwischen Mikrostruktur und magnetischen Eigenschaften von isotropen nanokristallinen (Nd,Pr)(Fe,Co)B-Permanentmagneten. Hochkoerzitive Magnete vom Typ (Nd,Pr)FeB wurden durch hochenergetisches Mahlen in der Kugelmühle oder Rascherstarrung hergestellt. Der Einfluss geringer Mengen von Zusätzen wie Dy und Zr und die Substitution von Nd durch Pr auf die magnetischen Eigenschaften wird dargestellt. Weiterhin wurde eine Einschätzung des Warmumformverhaltens dieser Materialien durchgeführt. Hochenergetisches Kugelmahlen einer Legierung mit der Anfangszusammensetzung Pr9Nd3Dy1Fe72Co8B6.9Zr0.1 führte, nach Glühbehandlung, zu fast einphasigem Magnetpulver mit einem maximalen Energieprodukt von (BH)max~140 kJm-3. Das hochenergetische Kugelmahlen wurde zu einer sehr vielseitigen Technik zur Herstellung hochleistungsfähiger Nanokompositmagnete weiterentwickelt. Das Zulegieren unterschiedlicher Anteile von weichmagnetischem alpha-Fe ist damit sehr effektiv möglich. Der Zusatz von 25 Gew.-% alpha-Fe führt zu einem hohen (BH)max=178kJm-3. Dies wird auf eine sehr effektive Austauschkopplung zwischen den hart- und weichmagnetischen Phasen zurückgeführt. Die Natur der intergranularen Wechselwirkungen kann durch die Wohlfarth´sche Remanenzanalyse (?deltaJ-plot¡§) beschrieben werden. Im speziellen wurden deltaJ-Diagramme für verschiedene (i) alpha-Fe Gehalte, (ii) Korngrößen und (iii) Austauschlängen erstellt. Es konnte gezeigt werden, dass in den Nanokompositmagneten auf Pr-Basis keine Spinumorientierung auftritt. Abschließend zeigt die Arbeit die Möglichkeit der Nutzung einer mechanisch aktivierten Gas-Festkörper-Reaktion auf, mit der eine sehr feinkörnige Mikrostruktur erhalten wird. Die Untersuchungen wurden mit stöchiometrischen Nd2(Fe1-xCox)14B-Legierungen begonnen (x=0-1). Die Verbindungen wurden unter höheren Wasserstoffdrücken und Temperaturen gemahlen, wodurch sie zu NdH2+delta und krz-(Fe,Co) (x=0-0.75) oder kfz-Co (x=1) entmischt wurden. Die Korngrößen des rekombinierten Nd2(Co,Fe)14B-Materials liegen im Bereich von 40-50 nm
Nanocrystalline permanent magnets present unusual magnetic properties because of surface/interface effects different from those of bulk or microcrystalline materials. This work presents results of a systematic investigation of the relationship between microstructure and magnetic properties in isotropic nanocrystalline (Nd,Pr)(Fe,Co)B permanent magnets. Highly coercive (Nd,Pr)FeB-type magnets have been produced using high energy ball milling and melt-spinning. The influence of small amounts of additives, Dy and Zr, and the substitution of Nd by Pr on the microstructural and magnetic properties are shown. An assessment of the hot deformation behaviour has been carried out. Intensive milling of an alloy with starting composition Pr9Nd3Dy1Fe72Co8B6.9Zr0.1 yields, after annealing treatment, nearly single-phase magnet powders with a maximum energy product (BH)max?î140kJm-3. Co has a beneficial effect on the intrinsic magnetic properties but also on the microstructure, with a mean grain size of 20nm. Intensive milling is used to produce high-performance nanocomposite magnets by blending this latter alloy with different fractions of soft magnetic alfa-Fe. Addition of 25wt.% alfa-Fe leads to a high (BH)max=178 kJm-3 due to an effective exchange-coupling between the hard and the soft magnetic phases. The intergrain interactions between the crystallites of the nanocomposite structure are analysed. Demagnetisation recoil loops of the nanocomposite magnets show relatively open minor loops due to the exchange-spring mechanism. Information about the intergrain interactions during demagnetisation are obtained by plotting the deviation of the demagnetising remanence from the Wohlfarth-model (¡§deltaJ-plot¡¨). Exchange-coupling phenomena are studied by analysing the evolution of the corresponding deltaJ values when varying (i) the alfa-Fe content, (ii) the annealing temperature, i.e. the grain size and (iii) the measurement temperature. Low temperature measurements do not reveal any sign of spin reorientation for these Pr-based nanocomposite magnets. The work concludes showing the possibility of using a mechanically activated gas-solid reaction to obtain an effective grain refined microstructure starting from stoichiometric Nd2(Fe1-xCox)14B alloys (x=0-1). These compounds were milled under enhanced hydrogen pressure and temperature leading to their disproportionation into NdH2+delta and bcc-(Fe,Co) (x=0-0.75) or fcc-Co (x=1). Grain sizes of recombined Nd2(Fe,Co)14B materials were found to be 40-50nm
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Aberra, Guebrou Samuel. "Influence des plasmons de surface propagatifs sur la cohérence de systèmes optiques." Phd thesis, Université Claude Bernard - Lyon I, 2012. http://tel.archives-ouvertes.fr/tel-00798779.

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Cette thèse expérimentale s'est attachée à l'étude des effets induits par l'extension spatiale desplasmons de surface sur l'émission de matériaux organiques et inorganiques. Le système estformé d'un ensemble d'émetteurs localisés émettant principalement des plasmons de surfacedélocalisés. Dans un premier temps, nous nous sommes intéressés à l'imagerie par microscopieplasmon, technique de plus en plus utilisée dans divers domaines, notamment la biologie. Nousavons montré que l'émission détectée en un point provient essentiellement de l'environnementet non du point observé, définissant ainsi un cercle d'influence lié à la longueur de propagationdu plasmon de surface. Quand le plasmon interagit plus fortement avec des émetteurs, ilpeut entrer en régime de couplage fort. Ce couplage fort se traduit par un changement dansles énergies du système et par l'apparition de nouveaux états hybrides excitons-plasmons, lespolaritons. Les différents émetteurs localisés (des chaines de colorants agrégés) ne sont alorsplus indépendants entre eux. Des mesures de diffusion montrent un effet collectif induit par lecouplage fort. Ces expériences ont été confirmées par des mesures de cohérence spatiale, réaliséesen ajoutant une expérience de fentes d'Young au dispositif de microscopie plasmon. Ilapparait qu'un état cohérent étendu sur plusieurs microns se forme, conformément aux prévisionsthéoriques. L'ensemble d'émetteurs se comporte alors comme une macromolécule, dontl'interaction est induite par le plasmon de surface.
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Books on the topic "J-couplings"

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Kachelriess, Michael. Quantum mechanics. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198802877.003.0002.

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After a brief review of the operator approach to quantum mechanics, Feynmans path integral, which expresses a transition amplitude as a sum over all paths, is derived. Adding a linear coupling to an external source J and a damping term to the Lagrangian, the ground-state persistence amplitude is obtained. This quantity serves as the generating functional Z[J] for n-point Green functions which are the main target when studying quantum field theory. Then the harmonic oscillator as an example for a one-dimensional quantum field theory is discussed and the reason why a relativistic quantum theory should be based on quantum fields is explained.
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Kelly, Phil. Defending Classical Geopolitics. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228637.013.279.

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Three successive parts are presented within this article, all intended to raise the visibility and show the utility of classical geopolitics as a deserving and separate international-relations model: (a) a common traditional definition, (b) relevant theories that correspond to that definition, and (c) applications of certain theories that will delve at some depth into three case studies (the Ukrainian shatterbelt, contemporary Turkish geopolitics, and a North American heartland).The placement of states, regions, and resources, as affecting international relations and foreign policies, defines classical geopolitics. This definition emphasizes the application of spatially composed unbiased theories that should bring insight into foreign-affairs events and policies. Specifically, a “model” contains theories that correspond to its description. A “theory” is a simple sentence of probability, with “A” happening to likely affect “B.” Importantly, models are passive; they merely hold theories. In contrast, theories possess their own titles and perform actively when taken from such models.Various methodological challenges are presented: (a) combining concepts with theories, (b) estimating probability for testing theories, (c) claiming the “scientific,” (d) accounting for determinism, (e) revealing a dynamic environment for geopolitics, (f) separating realism from geopolitics, and (g) drawing classical geopolitics away from the critical. Certain theories that are placed within the geopolitical model are examined next: (a) heartlands and rimlands, (b) land and sea power, (c) choke points and maritime lines of communication, (d) offshore balancing, (e) the Monroe doctrine, (f) balances of power, (g) checkerboards, (h) shatterbelts, (i) pan-regions, (j) influence spheres, (k) dependency, (l) buffer states, (m) organic borders, (n) imperial thesis, (o) borders/wars, (p) contagion, (q) irredentism, (r) demography, (s) fluvial laws, (t) petro-politics, and (u) catastrophic events in nature. Additional theories apply elsewhere in the article as well.Of the three case studies, the Ukrainian shatterbelt represents the sole contemporary geopolitical configuration of this type, a regional conflict coupling with a strategic rivalry. Here, partisans of the civil war between the eastern and the western sectors of the country have joined with the Russians against the Europeans and Americans, respectively. Next, Turkey’s pivotal location has afforded it both advantages and disadvantages, a topic discussed at some length earlier in the article. Its “zero-problems” strategy of seeking positive relations with neighbors has now been forced to change tactics, reflective of new forces within and beyond the country. Finally, a North American heartland compares nicely to Halford Mackinder’s earlier Eurasia heartland thesis, with the American perhaps proving more stable, wealthy, and enduring, based in large part on its stronger geopolitical features.
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Book chapters on the topic "J-couplings"

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Bagby, Stefan. "J Coupling." In Encyclopedia of Biophysics, 1163–68. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-16712-6_306.

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Lidzey, D. G., D. D. C. Bradley, A. Armitage, T. Virgili, M. S. Skolnick, and S. Walker. "Strong Coupling in Organic Semiconductor Microcavities Based on J-Aggregates." In Multiphoton and Light Driven Multielectron Processes in Organics: New Phenomena, Materials and Applications, 357–70. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4056-0_26.

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Sørensen, Ole W. "Principles of Multidimensional NMR Techniques for Measurement of J Coupling Constants." In Computational Aspects of the Study of Biological Macromolecules by Nuclear Magnetic Resonance Spectroscopy, 51–56. Boston, MA: Springer US, 1991. http://dx.doi.org/10.1007/978-1-4757-9794-7_4.

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Chen, Zhong, Yuqing Huang, Yanqin Lin, and Shuhui Cai. "Accurate Measurement of Small J Couplings." In Annual Reports on NMR Spectroscopy, 157–83. Elsevier, 2011. http://dx.doi.org/10.1016/b978-0-12-385857-3.00004-9.

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Claridge, Timothy D. W. "Separating shifts and couplings: J-resolved spectroscopy." In High-Resolution NMR Techniques in Organic Chemistry, 233–46. Elsevier, 2009. http://dx.doi.org/10.1016/s1460-1567(08)10007-1.

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Bax, Ad, Geerten W. Vuister, Stephan Grzesiek, Frank Delaglio, Andy C. Wang, Rolf Tschudin, and Guang Zhu. "[2] Measurement of homo- and heteronuclear J couplings from quantitative J correlation." In Methods in Enzymology, 79–105. Elsevier, 1994. http://dx.doi.org/10.1016/s0076-6879(94)39004-5.

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Taber, Douglass F. "The Krische Synthesis of Bryostatin 7." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0090.

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The bryostatins, as exemplified by bryostatin 75, are an exciting class of natural products. In addition to being effective antineoplastic agents, they show activity against Alzheimer’s disease. The central ring-forming step in the synthesis of 5 reported (J. Am. Chem. Soc. 2011, 133, 13876) by Michael J. Krische of the University of Texas, Austin is the triply convergent coupling of the chirons 1 and 2 with the linchpin reagent 3. The preparation of 1 and of 2 showcases the hydrogen transfer strategy for carbon–carbon bond construction developed by the Krische group. The synthesis of 2 began with the previously described double coupling of the simple starting materials 6 and 7. The product diol 8 had >99% ee. Ozonolysis of 8 was followed by a reductive coupling with the allene, which installed the gem dimethyl substituents of 2, and also the third oxygenated stereogenic center. The preparation of 1 proceeded from the aldehyde 10, prepared by Sharpless asymmetric dihydroxylation of 3-pentenenitrile. The chelate-controlled addition of propargyl zinc 11 led to the alkyne 12. Reductive coupling of the alkyne of 12 with the aldehyde of 13, again following a Krische procedure, delivered 1. The triply convergent Keck-Yu condensation of 1 with 3, and then with 2, gave, after some manipulation, the desired tetrahydropyran 4. Selective hydrolysis of the methyl ester in the presence of the acetates followed by selective silylation of two of the three secondary hydroxyls gave a suitable substrate for Yamaguchi cyclization to give 14. Selective oxidative cleavage of two of the three alkenes then gave an intermediate keto aldehyde that was carried on to bryostatin 7 5 following known procedures. The key to the synthesis of the complex bryostatin 7 5 was the ready supply of the chirons 1 and 2, prepared by the simple but powerful enantioselective reductive couplings developed by the Krische group. These couplings will have many other applications in target-directed synthesis.
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"Chapter 7 Separating shifts and couplings: J-resolved spectroscopy." In High-Resolution NMR Techniques in Organic Chemistry, 259–75. Elsevier, 1999. http://dx.doi.org/10.1016/s1460-1567(99)80010-5.

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Salvador, Pedro. "Dependencies of J-Couplings upon Dihedral Angles on Proteins." In Annual Reports on NMR Spectroscopy, 185–227. Elsevier, 2014. http://dx.doi.org/10.1016/b978-0-12-800185-1.00005-x.

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Claridge, Timothy D. W. "Separating Shifts and Couplings: J-Resolved and Pure Shift Spectroscopy." In High-Resolution NMR Techniques in Organic Chemistry, 295–313. Elsevier, 2016. http://dx.doi.org/10.1016/b978-0-08-099986-9.00008-7.

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Conference papers on the topic "J-couplings"

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Lehotai, Levente, Szabolcs Tóth, Viktor Pajer, Imre Seres, János Csontos, Ádám Börzsönyi, Károly Osvay, et al. "Advanced numerical simulation of high energy thin plate post-compression in 3+1D." In Advanced Solid State Lasers. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/assl.2022.jw3a.9.

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Energy scaling of the thin-plate post-compression technique was investigated with pulse energies up to 10 J by utilizing a novel 3+1D numerical simulation environment, with special focus on the few-to-single-cycle temporal regime and spatio-temporal couplings.
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Zaradny, Marek Bogdan. "Direct-coupled-resonators bandpass filters with arbitral end-coupled-series-immittances: Aspect of the couplings among terminations and resonators with arbitral non-inertive and inertive immittnaces and J-inverters." In 2017 MIXDES - 24th International Conference "Mixed Design of Integrated Circuits and Systems". IEEE, 2017. http://dx.doi.org/10.23919/mixdes.2017.8005266.

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Takano, Junpei, Susumu Igarashi, Alexander Molodozhentsev, and Hirohiko Someya. "Linear Coupling Resonance Correction of the J-PARC Main Ring." In Proceedings of the 2nd International Symposium on Science at J-PARC — Unlocking the Mysteries of Life, Matter and the Universe —. Journal of the Physical Society of Japan, 2015. http://dx.doi.org/10.7566/jpscp.8.012022.

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Das, Kamalika, Bidhan Hazra, and Manbendra Chandra. "Plasmon-exciton coupling in hollow gold nanoprisms -J-aggregate hybrids." In International Conference on Fibre Optics and Photonics. Washington, D.C.: OSA, 2016. http://dx.doi.org/10.1364/photonics.2016.th2e.1.

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Bethardy, G. A., Jungsug Go, and David S. Perry. "Experimental evidence for distinct classes of coupling mechanism in intramolecular vibrational redistribution." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/oam.1991.thq3.

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Sub-Doppler infrared absorption spectra of jet- cooled 1-butyne and trans-ethanol exhibit contrasting patterns of molecular eigenstates. In the presence of intramolecular vibration energy redistribution, frequency resolved spectra reveal that transitions to zero order upper state, v, J, K a , K c levels are fragmented into clumps of molecular eigenstates. The number and frequencies of these discrete features contain information about the nature of the intramolecular coupling. In the methyl C-H stretch of ethanol at 2990 cm-1 between J = 0 to 2, the number of coupled states increases sharply and is comparable to the rovibrational state density. In contrast, the actetylenic and methyl C-H stretches of 1-butyne at 3333 cm-1, respectively, exhibit coupling that is approximately independent of J and coupled state densities comparable to the purely vibrational state density. It is therefore concluded that a rotationally mediated coupling mechanism such as Coriolis or centrifugal coupling is involved in ethanol whereas only anharmonic coupling is apparent in 1-butyne.
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Esteban, R., D. Melnikau, D. Savateeva, A. Sanchez-Iglesias, M. Grzelczak, M. K. Schmidt, L. M. Liz-Marzan, J. Aizpurua, and Y. P. Rakovich. "Strong coupling detected in the photoluminescence of J-aggregate/plasmon hybrid systems." In 2016 Progress in Electromagnetic Research Symposium (PIERS). IEEE, 2016. http://dx.doi.org/10.1109/piers.2016.7734490.

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Gimatdin, Rifat, Pavel Kupriyanov, Georgy Mozzhukhin, Bulat Rameev, and Vladimir Chizhik. "J-coupling in NMR-spectra of Organophosphorus Liquids in Earth's Magnetic Field." In 2023 Photonics & Electromagnetics Research Symposium (PIERS). IEEE, 2023. http://dx.doi.org/10.1109/piers59004.2023.10221331.

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Gonzalez, Jorge, Karl N. Kirschner, Maral Basma, and Robert J. Woods. "A NON-EMPIRICAL APPROACH TO DETERMINING ROTAMER POPULATIONS FROM SCALAR J-COUPLING VALUES." In XXIst International Carbohydrate Symposium 2002. TheScientificWorld Ltd, 2002. http://dx.doi.org/10.1100/tsw.2002.482.

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Anwar, Muhammad Sufian, Hamza Nawaz, Arslan Kiyani, and Muhammad Ali Babar Abbasi. "Mixed coupled quarter-wavelength resonator filter utilizing J/K inverters and coupling-path phases." In 2020 International Conference on UK-China Emerging Technologies (UCET). IEEE, 2020. http://dx.doi.org/10.1109/ucet51115.2020.9205371.

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Wang, Hai, Andrea Toma, Haiyu Wang, Hong-Bo Sun, and Remo Proietti Zaccaria. "Dynamics between J-aggregates and surface plasmon polaritons in strong coupling regime (Conference Presentation)." In Nanoimaging and Nanospectroscopy IV, edited by Prabhat Verma and Alexander Egner. SPIE, 2016. http://dx.doi.org/10.1117/12.2240072.

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