Weighted Composition Operators between Different Hardy Spaces

Let and be two analytic functions defined on such that. The operator given by is called a weighted composition operator. In this paper we deal with the boundedness, compactness, weak compactness, and complete continuity of weighted composition operators from a Hardy space H _p into another Hardy space H _q . We apply these results to study composition operators on Hardy spaces of a half-plane. Submitted: November 20, 2001.     

L2 orbital stability of Dirac solitons in the massive Thirring model

We prove L² orbital stability of Dirac solitons in the massive Thirring model. Our method uses local well posedness of the massive Thirring model in L², conservation of the charge functional, and the auto–Bäcklund transformation. The latter transformation exists because the massive Thirring model is integrable via the inverse scattering transform method.     

Improvement in the physicochemical properties of titanium dioxide by surface modification with 1H-1-carboxylate of isopropyl-imidazole and 3-aminopropyltrimethoxysilane: case study—as a filler in polylactic acid composites

Journal of Thermal Analysis and Calorimetry - This work presents the surface functionalization of titanium dioxide nanoparticles with 1H-1-carboxylate of isopropyl-imidazole and...     

A decision-making tool for project investments based on real options: the case of wind power generation

This paper presents how to apply a decision-making tool based on real options to assess the investment in a wind energy plant.     

Applications of N′-alkylated derivatives of TsDPEN in the asymmetric transfer hydrogenation of CO and CN bonds

Arene/Ru(II) complexes of (R,R)-N-alkyl-TsDPEN ligands are effective in the asymmetric transfer hydrogenation of ketones and imines in formic acid/triethylamine solution. The complex derived from the N′-Bn derivative of TsDPEN reduces monocyclic imines in up to 60% ee, whilst the N′-Me derivative of TsDPEN forms a more active catalyst than the non-alkylated analogue and reduces ketones in up to 97% ee.     

On the convergence of FPT-DFT calculations of the Fermi contact contribution to NMR coupling constants

Calculations of the Fermi contact term of NMR couplings, J^FC(MN), using a single FC perturbation within the Finite Perturbation Theory-DFT frameworks are only reliable if they do not depend either on a) the size of the perturbation, and b) whether the perturbation is placed at the site of the M or N nucleus. In this short communication these two points are addressed by studying the ¹J^FC(MN) and ²J^FC(MN) linear response behavior in a set of small molecules. It is shown how such a linearity depends on the size of the finite perturbation, the basis set employed, and the chosen nucleus site. The dependence of SCF convergence requirements on the size of the perturbation is also discussed. Calculations are carried out employing the B3LYP and B3PW91 hybrid functionals and results are compared with both state-of-the-art calculations and experimental values. Received: 28 June 2000 / Accepted: 12 July 2000 / Published online: 23 November 2000     

Aminodiphenylphosphanes: Isotope‐induced chemical shifts 1Δ14/15N(31P), coupling constants 1J(31P,15N), and chemical shifts δ15N and δ31P

A series of aminodiphenylphosphanes 1 [Ph₂P‐N(H)tBu ( a ), ‐NEt₂ ( b ), ‐NiPr₂ ( c )], 2 [Ph₂P‐NHPh ( a ), ‐NH‐2‐pyridine ( b ), ‐NH‐3‐pyridine ( c ), ‐NH‐4‐pyridine ( d ), NH‐pyrimidine ( e ), NH‐2,6‐Me₂‐C₆H₃ ( f ), NH‐3‐Me‐2‐pyridine ( g )], 3 [Ph₂P‐N(Me)Ph ( a ), ‐NPh₂ ( b )], and N‐pyrrolyldiphenylphosphane 4 (Ph₂P‐NC₄H₄) was prepared and studied by NMR (¹H, ¹³C, ³¹P, ¹⁵N NMR) spectroscopy. The isotope‐induced chemical shifts ¹Δ^14/15N(³¹P) were determined at natural abundance of ¹⁵N by using HEED INEPT experiments. A dependence of ¹Δ^14/15N(³¹P) on the substituents at nitrogen was found (alkyl < H < aryl; increasingly negative values). The magnitude and sign of the coupling constants ¹J(³¹P,¹⁵N) (positive sign) are dominated by the presence of the lone pair of electrons at the phosphorus atom. The X‐ray structural analysis of 2b is reported, showing the presence of dimers owing to intermolecular hydrogen bridges in the solid state. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:542–550, 2001     

Synthesis of Phosphanes Bearing 2‐Imino‐1,3‐thiazolidine Ligands – X‐Ray Analyses and NMR Spectroscopy

Pseudo‐ephedrine derived 2‐imino‐1,3‐thiazolidine 1 reacts with tris(diethylamino)phosphane by stepwise replacement of the diethylamino group to give the mono‐, bis‐ and tris(imino)phosphanes 2 , 3 and 4 , respectively, of which 4 could be isolated in pure state. The analogous reaction with diethylamino‐diphenylphosphane affords the imino‐diphenylphosphane 5 . The iminophosphanes react with sulfur or selenium to give the corresponding phosphorus(V) compounds. In contrast, the reaction of the iminophosphanes with oxygen is very slow; anhydrous trimethylamine N‐oxide reacts in the melt with the phosphanes to give the oxides 4(O) and 5(O) . The molecular structures of 4(O) (in mixture with 4 ), 4(Se) , 5(S) and 5(Se) were determined by X‐ray analysis. In all cases the ring‐sulfur and the phosphorus atoms are in cis‐positions at the C=N bonds. The analogous solution structures were determined by ¹H, ¹³C, ¹⁵N, ³¹P and ⁷⁷Se NMR spectroscopy. In the case of the compounds 5 , 5(O) , 5(S) and 5(Se) the isotope‐induced chemical shifts ¹δ^14/15N(³¹P) were determined, using INEPT‐HEED experiments.     

Implementation of atomic basis set composed of 1s Gaussian and 1s Slater-type orbitals to carry out quantum mechanics molecular calculations

A mixed atomic basis set formed with ls Slater-type orbitals and 1s floating spherical Gaussian orbitals is implemented. Evaluation of multicenter integrals is carried out using a method based on expansion of binary products of atomic basis functions in terms of a complete basis set, and a systematic analysis is performed. The proposed algorithm is very stable and furnishes fairly good results for total energy and geometry. An LCAO-SCF test calculation is carried out on LiH. The trends observed show that there are some combinations of mixed orbitals that are appropriate to describe the system. ©1999 John Wiley & Sons, Inc. J Comput Chem 20: 604–609, 1999     

Versatile behavior of 2-guanidinobenzimidazole nitrogen atoms toward protonation,coordination and methylation

The structure, dynamic behavior, protonation, methylation, and coordination sites of 2-guanidinobenzimidazole 1a were investigated. Structures of compounds [2-guanidinium-1,3,10-trihydrobenzimidazole]sulfate 1b , [2-guanidinium-1,3-dihydro-benzimidazole]sulfate 1c–1d , [2-guanidinium-1,3-dihydro-benzimidazole]tetrafluoroborate 1e , [2-guanidinium-1,3-dihydro-benzimidazole]chloride 1f , [2-guanidinium-1,3-dihydro-benzimidazole] perchlorate 1g , 2-guanidino-1-methyl-benzimidazole 2a , [2-guanidinium-1,3-dimethyl-benzimidazole]iodide 2b , [2-guanidinium-1-methyl-3-hydro-benzimidazole]chloride 2c , [2-guanidinium-1,10-dihydro-benzimidazole]acetate 3 , 2-guanidino-1-hydro-3-borane-benzimidazole 4a , 2-guanidino-1-methyl-3-borane-benzimidazole 4b , (2-guanidino-benzimidazole)dimethyltin 5 , [bis(2-guanidino-10-hydro-benzimidazole)nickel(II)] 6 , and [bis(2-guanidino-1,10-dihydro-benzimidazole)zinc(II)]nitrate 7 were determined based on ¹H, ¹³C, and ¹⁵N NMR spectroscopy. The X-ray diffraction structures of 2a, 2b, 3, 6 , and 7 were obtained. The results show that 1a has an open structure without an intramolecular hydrogen bond in DMSO or DMF. The imidazolic N-3 is the preferred basic site in solution for protonation, methylation, and coordination and not N-10 as was suggested from semiempirical calculations. Under strong acidic conditions, diprotonation occurs at N-3 and N-10. In the solid state, 3 and 6 were protonated preferently at N10 rather than at N-1. © 1997 John Wiley & Sons, Inc. Heteroatom Chem 8: 397–410, 1997