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81.
The main result of the present note states that it is consistent with the ZFC axioms of set theory (relying on Martin's Maximum MM axiom), that every Asplund space of density character ω1 has a renorming with the Mazur intersection property. Combined with the previous result of Jiménez and Moreno (based upon the work of Kunen under the continuum hypothesis) we obtain that the MIP renormability of Asplund spaces of density ω1 is undecidable in ZFC. 相似文献
82.
Summary In this work we re-examine the pole approximation frequently utilized to treat the interference between radiative emission
and autoionization. Special attention is accorded to the normalization of the diagonalized final states and we discuss their
possible implications.
To speed up publication, the authors of this paper have agreed to not receive the proofs for correction. 相似文献
83.
The aim of this work was construction of the new wavelet function and verification that a continuous wavelet transform with a specially defined dedicated mother wavelet is a useful tool for precise detection of end-point in a potentiometric titration. The proposed algorithm does not require any initial information about the nature or the type of analyte and/or the shape of the titration curve. The signal imperfection, as well as random noise or spikes has no influence on the operation of the procedure.The optimization of the new algorithm was done using simulated curves and next experimental data were considered. In the case of well-shaped and noise-free titration data, the proposed method gives the same accuracy and precision as commonly used algorithms. But, in the case of noisy or badly shaped curves, the presented approach works good (relative error mainly below 2% and coefficients of variability below 5%) while traditional procedures fail. Therefore, the proposed algorithm may be useful in interpretation of the experimental data and also in automation of the typical titration analysis, specially in the case when random noise interfere with analytical signal. 相似文献
84.
Avcı Davut Altürk Sümeyye Sönmez Fatih Tamer Ömer Başoğlu Adil Atalay Yusuf Zengin Kurt Belma Dege Necmi 《Molecular diversity》2021,25(1):171-189
Molecular Diversity - The World Health Organization (WHO) report shows that diabetes mellitus (DM) will be one of the ten deadly diseases in the near future. The best way to prevent DM is to... 相似文献
85.
Antigoni Kotali Anna Maniadaki Elvira Kotali Philip A. Harris Ewa Różycka-Sokołowska Piotr Bałczewski John A. Joule 《Tetrahedron letters》2017,58(6):512-515
A series of 4-phenyl-2-aryl-8-methyl-6-oxo-7-phenylhydrazo-2H,4H,6H,7H,8H[1,3,4,2]-oxadiazaborolo[2,3-b][1,3,2]oxazaborines were prepared in high yields via the reaction of phenylboronic acid with various N-acylhydrazones of 3-keto-2-(2′-phenylhydrazono) butanoic acid in the presence of 4 Å molecular sieves. These derivatives represent a novel class of zwitterionic, tetrahedral boron heterocycles. Single crystal X-ray analysis of a representative boron containing product is reported. 相似文献
86.
Linkui Bai Linxiang Cai Qinghua Liu Yunxu Qian Bo Yang 《Journal of Coordination Chemistry》2017,70(22):3759-3768
A series of novel dinuclear platinum(II) complexes with a chiral tetradentate ligand, (1R,1′R,2R,2′R)-N1,N1′-(1,2-phenylenebis(methylene))dicyclohexane-1,2-diamine (HL), and mono-carboxylic acid derivatives as ligands have been designed, synthesized, and characterized. In vitro cytotoxicity evaluation of synthesized complexes against human HepG-2, A549, HCT-116, and MCF-7 cancer cell lines has been conducted by MTT assays. All compounds showed antitumor activity to HepG-2 and HCT-116 cell lines. Compound L2 exhibited better cytotoxicity than that of carboplatin against HepG-2 and A549 cell lines and also showed comparable activity against HCT-116 cell line. 相似文献
87.
V. Torres-Zúñiga O. G. Morales-Saavedra E. Rivera R. Castañeda-Guzmán J. G. Bañuelos R. Ortega-Martínez 《Journal of Sol-Gel Science and Technology》2010,56(1):7-18
SiO2-based bulk and film sol–gel hybrid materials were prepared with a family of novel liquid crystalline (LC) amphiphilic azo-dyes
bearing oligo(ethylene glycol) spacers (named here RED-PEG-n, n = 2, 3, 4, 6). The catalyst-free-sonogel route was implemented to produce optically active hybrid monoliths and spin-coated
films with these materials. Comprehensive morphological, thermal, photo-acoustic and spectroscopic sample characterizations
were performed in order to elucidate the physical properties of these novel compounds within the sonogel environment. Film
samples were also studied via the nonlinear optical (NLO) second harmonic generation (SHG)-Maker fringes technique. Results
show that the chromophores were homogeneously embedded within the highly pure SiO2-sonogel network, showing a clear thermotropic mesogenic behavior. The push–pull structure of the implemented azo-dyes allowed
effective electrically-induced monomeric alignment within the sonogel confinement; thus, stable quadratic NLO-SHG-activity
in the organic–inorganic film samples was achieved despite the lack of glass transition temperature (T
g
) of the guest LC-compounds. 相似文献
88.
89.
Fatou Ba 《Tetrahedron letters》2010,51(4):605-608
Push-pull methylenepyran compounds 3 containing ferrocenyl or aryl groups are synthesized from reaction of condensation between γ-methyl-pyrylium salts 1 as precursors of γ-methylenepyrans and alkynylcarbene complexes 2 as Michaël-type acceptors. The new carbenes 3 evolve in CH2Cl2 solution at room temperature to provide spiro-fused-pyran-cyclopentenenone 4 and polysubstituted cyclopentenones 5. 相似文献
90.
Ümmühan Ocak Miraç Ocak Aysel Başoğlu Semanur Parlayan Dilek Başaran Hakan Alp Halit Kantekin 《Polyhedron》2010
A series of crown ethers carrying an anthracene group with nitrogen–sulfur donor atom, which differ in having three, four and five sulfur atoms in the macrocycle was designed and synthesized by the reaction of the corresponding macrocyclic compound and 9-chloromethyl-anthracene. The influence of metal cations such as Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ on the spectroscopic properties of the ligands was investigated in acetonitrile–dichloromethane (1:1) by means of absorption and emission spectrometry. Absorption spectra show isosbestic points in the spectrophotometric titration of Al3+, Zn2+, Fe2+, Fe3+, Cu2+, Hg2+ and Pb2+ the results of which disclosed the complexation compositions and complex stability constants of the novel ligands with these cations. The monoazapentathia crown ether showed sensitivity for Al3+ with linear range and detection limit of 2.6 × 10−6 M–2.6 × 10−5 M and 8.1 × 10−7 M, respectively. 相似文献