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991.
Gerhard H. Findenegg Prof. Dr. Susanne Jähnert Dr. Dilek Akcakayiran Dr. Andreas Schreiber Dr. 《Chemphyschem》2008,9(18):2651-2659
In nanosized pores, liquid water can be thermodynamically stable down to temperatures well below the limit of homogeneous nucleation of bulk water (~235 K). Studies of water in such pores therefore offer an opportunity to reveal the anomalous behavior of deeply supercooled water. Herein we focus on recent studies of the limits of freezing and melting of water in the cylindrical pores of ordered mesoporous silicas with pore diameters in the range of 2–10 nm, based on vapor sorption measurements, calorimetric studies, NMR spectroscopy and cryoporometry, and neutron diffraction studies. 相似文献
992.
993.
Keller Hildegard Langer Elisabeth Lehner Harald Derflinger Gerhard 《Theoretical chemistry accounts》1978,49(2):93-100
The Algebraic Theory of Chirality Functions is derived by means of exclusively qualitative considerations. Hence, the significance of quantitative results is questionable. Moreover the construction of “Näherungsansätze” (”Approximation-Ansatz”), which may be interpreted as semiempirical methods, is achieved on the basis of plausibility and mathematical simplicity. Since physical arguments are not included, the consistency or inconsistency of “Näherungsansätze” with experimental results do not justify direct physical conclusions. 相似文献
994.
Dedicated to Professor Gerhard Kempter on the occasion of his 70th birthday Quinoxaline‐2‐aldoximes and ‐ketoximes ( 6 ) react with hydrazine, alkylhydrazines or arylhydrazines under acidic conditions to afford lH‐pyrazolo[3,4‐b]quinoxalines (flavazoles) ( 1 ). Since the oximes ( 6 ) are easily available from phenylenediamine, the herein described methodology provides a convenient two step entry to various functionalized flavazoles. Furthermore, acylation and alkylation of the 1‐unsubstituted lH‐pyrazolo[3,4‐b]quinoxalines 7 proceeds smoothly and in good yield to afford 31 different flavazoles 11 and 12. 相似文献
995.
Isothermal pressure (p)-mass fraction (w) phase diagrams were measured for CO2 + tetradecanoic acid at six temperatures from 328.2 K to 373.2 K and for CO2 + docosane at four temperatures from 343.2 K to 393.2 K as well as isobaric temperature (T)-mass fraction (w) phase diagrams for both systems at 34.5 MPa. In addition the isothermal and isobaric Gibbs phase prisms at 373.2 K and 34.5 MPa respectively were determined for the ternary system CO2 + tetradecanoic acid + docosane, and and isobaric miscibility window was found between 333 K and 385 K at 34.5 MPa. 相似文献
996.
D. Gerhard A. Hellweg I. Merke W. Stahl M. Baudelet D. Petitprez G. Wlodarczak 《Journal of Molecular Spectroscopy》2003,220(2):234-241
The microwave spectrum of o-chlorotoluene has been reinvestigated using molecular beam Fourier transform microwave (MB-FTMW) spectrometers in the frequency range of 4–23 GHz. Due to the high resolution of this molecular beam technique the analysis yielded improved rotational constants, centrifugal distortion constants, and, for the first time, the complete chlorine nuclear quadrupole coupling tensor. From the torsional fine structure the barrier to internal rotation of the methyl group was found to be 5.5798(52) kJ mol−1. Experimental results and ab initio calculations are compared. 相似文献
997.
998.
Lung Cancer: EGFR Inhibitors with Low Nanomolar Activity against a Therapy‐Resistant L858R/T790M/C797S Mutant
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Marcel Günther Michael Juchum Dr. Gerhard Kelter Prof. Dr. Heiner Fiebig Prof. Dr. Stefan Laufer 《Angewandte Chemie (International ed. in English)》2016,55(36):10890-10894
The treatment of non‐small‐cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) inhibitors is made challenging by acquired resistance caused by somatic mutations. Third‐generation EGFR inhibitors have been designed to overcome resistance through covalent binding to the Cys 797 residue of the enzyme, and these inhibitors are effective against most clinically relevant EGFR mutants. However, the high dependence of these recent EGFR inhibitors on this particular interaction means that additional mutation of Cys 797 results in poor inhibitory activity, which leads to tumor relapse in initially responding patients. A new generation of irreversible and reversible mutant EGFR inhibitors was developed with strong noncovalent binding properties, and these compounds show high inhibitory activities against the cysteine‐mutated L858R/T790M/C797S EGFR. 相似文献
999.
Wolfgang A. Herrmann Gerhard M. Lobmaier Martina Elison 《Journal of organometallic chemistry》1996,520(1-2):231-234
Oxometal complexes of molybdenum and tungsten in high oxidation states from stable adducts with 1,3-dimethylimidazoline-2-ylidene (L) 1. The first ‘carbene’ complexes of molybdenum(VI) [MoO2Cl(L)3]Cl (3a) and tungsten(VI) WO2Cl2(L)2 (4b) are reported. 相似文献
1000.
Jian-ping Gu Gerhard Hirsch Robert J. Buenker Ioannis D. Petsalakis Giannoula Theodorakopoulos Ming-bao Huang 《Chemical physics letters》1994,230(6):473-479
Ab initio MRD-CI calculations have been carried out on the ground and the eight lowest excited electronic states of LiAr, correlating with excited Li atom states up to 3d 2D. The ground (X2∑+ (2s)) and 2 2Σ+ (2p) electronic states are repulsive while the higher excited states show shallow Rydberg minima. Rates of radiative bound-bound and bound-free transitions have been also calculated. 相似文献