Results 41 to 50 of about 615,749 (292)

The hydrogen atom in electric and magnetic fields : Pauli's 1926 article

, 2002
The results obtained by Pauli, in his 1926 article on the hydrogen atom, made essential use of the dynamical so(4) symmetry of the bound states. Pauli used this symmetry to compute the perturbed energy levels of an hydrogen atom in a uniform electric ...
Becker H. G., Luc-Koenig E., Solov’ev E. A.   +2 more
core   +1 more source

Structural insights into an engineered feruloyl esterase with improved MHET degrading properties

FEBS Letters, EarlyView.
A feruloyl esterase was engineered to mimic key features of MHETase, enhancing the degradation of PET oligomers. Structural and computational analysis reveal how a point mutation stabilizes the active site and reshapes the binding cleft, expading substrate scope.
Panagiota Karampa, Konstantinos Makryniotis, Theofani‐Iosifina Sousani, Evangelos Topakas, Vangelis Daskalakis, Maria Dimarogona   +5 more
wiley   +1 more source

Is Schr\"{o}dinger's Conjecture for the Hydrogen Atom Coherent States Attainable

, 1993
We construct the most general SO(4,2) hydrogen atom coherent states which are the counterpart of Schr\"{o}dinger's harmonic oscillator coherent states. We show that these states cannot be localized and cannot follow the classical orbits.
A. O. Barut, B.G. Wybourne, D. Gaeta, Jr., Da Hsuan Feng, E. Schrödinger, Ivaylo Zlatev@f, J. A. Yeazell, J. A. Yeazell, Jr., J. Mostowski, J.C. Gay, L. Moorman, L.S. Brown, M. Nauenberg, R. Gilmore, R. Glauber, R. Shankar, Wei Min Zhang, Wei-Min Zhang@f   +17 more
core   +1 more source

A Reaction‐Induced Localization of Spin Density Enables Thermal C−H Bond Activation of Methane by Pristine FeC4+ [PDF]

, 2019
The reactivity of the cationic metal‐carbon cluster FeC4+ towards methane has been studied experimentally using Fourier‐transform ion cyclotron resonance mass spectrometry and computationally by high‐level quantum chemical calculations.
Geng, Caiyun, Li, Jilai, Schwarz, Helmut, Weiske, Thomas   +3 more
core   +1 more source

A methionine‐lined active site governs carbocation stabilization and product specificity in a bacterial terpene synthase

FEBS Letters, EarlyView.
This study reveals a unique active site enriched in methionine residues and demonstrates that these residues play a critical role by stabilizing carbocation intermediates through novel sulfur–cation interactions. Structure‐guided mutagenesis further revealed variants with significantly altered product profiles, enhancing pseudopterosin formation. These
Marion Ringel, Carl P. O. Helmer, Shani Zev, Ronja Driller, Emily Buhr, Markus Reinbold, Renana Schwartz, Gabriel Foley, Mikael Boden, Daniel Garbe, Gerhard Schenk, Dan Thomas Major, Bernhard Loll, Thomas Brück   +13 more
wiley   +1 more source

Noncommutative Coulombic Monopole

, 2005
We have constructed the appropriate Hamiltonian of the noncommutative coulombic monopole (i.e. the noncommutative hydrogen atom with a monopole). The energy levels of this system have been calculated, discussed and compared with the noncommutative ...
Armen Yeranyan, D. A. Varshalovich, E. Witten, L. D. Landau, Stefano Bellucci   +4 more
core   +1 more source

Engineered extracellular vesicles enriched with the miR‐214/199a cluster enhance the efficacy of chemotherapy in ovarian cancer

Molecular Oncology, EarlyView.
Loss of the miR‐214/199a cluster is associated with recurrence in ovarian cancer. Engineered small extracellular vesicles (m214‐sEVs) elevate miR‐214‐3p/miR‐199a‐5p in tumor cells, suppress β‐catenin, TLR4, and YKT6 signaling, reprogram tumor‐derived sEV cargo, reduce chemoresistance and migration, and enhance carboplatin efficacy and survival in ...
Weida Wang, Ayesha Alvero, Yi Qin, Mingjin Wang, Alexandra Fox, Yanfeng Li, Michael Millman, Amy Kemper, Gil Mor, Xian Shuang Liu, Michael Chopp, Zheng Gang Zhang, Yi Zhang   +12 more
wiley   +1 more source

8-[(1E)-1-(2-Aminophenyliminio)ethyl]-2-oxo-2H-chromen-7-olate

Acta Crystallographica Section E, 2010
The title Schiff base, C17H14N2O3, exists as an NH tautomer with the H atom of the phenol group transferred to the imine N atom. The iminium H atom is involved in a strong intramolecular N+—H...O− hydrogen bond to the phenolate O atom,
E. S. Aazam, A. F. El Husseiny, H. M. Al-Amri, Orhan Büyükgüngör   +3 more
doaj   +1 more source

Semi-classical analysis of real atomic spectra beyond Gutzwiller's approximation

, 2005
Real atomic systems, like the hydrogen atom in a magnetic field or the helium atom, whose classical dynamics are chaotic, generally present both discrete and continuous symmetries.
Benoît Grémaud, D. Delande, E. P. Bogomolny, E. P. Bogomolny, K. Weibert, L. S. Schulmann, M. C. Gutzwiller   +6 more
core   +1 more source

Hydrogen-bonding interactions in the crystalline-phase structures of cinnamic acid derivatives [PDF]

, 1999
Secondary interactions responsible for the crystalline-phase structures of various cinnamic acids and cinnamic acid esters drawn from the Cambridge Structural Database were studied with the help of the Cerius package implemented on an SGI workstation ...
Pálinkó, István
core   +1 more source