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81.
Andriy Panasyuk 《Annals of Global Analysis and Geometry》1997,15(4):313-324
Given a complex manifold Mi, structures of Poisson algebras on (Mi)=C(Mi,C) which are associated with a nondegenerate -closed (2,0)-form i on Mi are considered. It is shown that every isomorphism of Poisson structures (M1) (M2) is generated by a biholomorphic map :M2 M1 such that 2 = *1 相似文献
82.
Moralez JG Raez J Yamazaki T Motkuri RK Kovalenko A Fenniri H 《Journal of the American Chemical Society》2005,127(23):8307-8309
The design of nanostructured materials with tunable dimensions and properties that maintain their structural integrity under physiological conditions is a major challenge in biomedical engineering and nanomedicine. Helical rosette nanotubes (HRN) are a new class of materials produced through a hierarchical self-assembly process of low molecular weight synthetic organic modules in water. Here, we describe a synthetic strategy to tune their stability and hierarchy by preorganization of the self-assembling units, control of net charge per unit of nanotube surface area, amphiphilicity, and number of H-bonds per self-assembling module, and through peripheral steric (de)compression. Using these criteria, HRNs with tunable stability and hierarchical architecture were produced from self-assembling modules that (a) persist as individual molecules in solution, (b) self-assemble into HRN but denature at high temperature (<85 degrees C), (c) self-assemble into HRN whose structural integrity persists even in boiling water (>95 degrees C), and (d) self-assemble into well-dispersed short nanotubes, long nanotubes, ribbons, or superhelices. Given the biocompatibility, synthetic accessibility, and chemical and physical tunability of these materials, numerous applications in biomedical engineering, materials science, and nanoscience and technology are envisioned. 相似文献
83.
A series of conjugates of peptide nucleic acids (PNA) and Zr(IV) complexes was prepared. Their ability to hydrolyze DNA was tested using MALDI-TOF mass spectrometry and HPLC. The most efficient artificial restriction enzyme found, PNA conjugate with Zr(IV) complex of tris(hydroxymethyl)-aminomethane, cleaves DNA targets sequence selectively in close proximity to the Zr(IV) complex. It was demonstrated that cleavage products are substrates of terminal transferase. 相似文献
84.
Oleg Kasyan Elisabeth R. Healey Andriy Drapailo Mike Zaworotko Sebastien Cecillon Anthony W. Coleman Vitaly Kalchenko 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(1-2):127-132
The synthesis and X-ray structure investigation of the cone shaped monodecyloxythiacalix[4]arene, as well as the introduction of the reactive bromide or chloromethyl groups on it’s
upper rim are described. Preparation of the amphiphilic derivative of thiacalixarene bearing three hydrophilic diethoxyphosphoryl
groups at the upper rim and lipophilic decyloxy group at the lower rim is presented. 相似文献
85.
Yakovenko Georgiy G. Lukianov Oleh А. Bol’but Andriy V. Vovk Mikhailo V. 《Chemistry of Heterocyclic Compounds》2019,55(12):1211-1216
Chemistry of Heterocyclic Compounds - N-Boc-protected 5-formyl-1H-pyrazol-4-amines react with malonic acid in pyridine in the presence of pyrrolidine at 45–50°С or with malonic... 相似文献
86.
The anisotropic formation of elongated metal-oxide aggregates in water under intensive stirring is analyzed. It is treated in terms of anisotropic ballistically mediated aggregation kinetics in open systems. The basic kinetic equations describing the stages of homogeneous nucleation, independent growth, and ripening of the aggregates are formulated for the open system under the external influence with the stirring intensity as the main parameter governing the process. The most significant elongation of the aggregates is shown to evolve at the ripening stage. 相似文献
87.
David Smith Andriy Pysanenko Patrik Španěl 《Rapid communications in mass spectrometry : RCM》2010,24(7):1066-1074
A study has been carried out of the decay of ethanol in mouth‐exhaled and nose‐exhaled breath of two healthy volunteers following the ingestion of various doses of alcohol at different dilutions in water. Concurrent analyses of sequential single breath exhalations from the two volunteers were carried out using selected ion flow tube mass spectrometry, SIFT‐MS, on‐line and in real time continuously over some 200 min following each alcohol dose by simply switching sampling between the two volunteers. Thus, the time interval between breath exhalations was only a few minutes, and this results in well‐defined decay curves. Inspection of the mouth‐exhaled and nose‐exhaled breath data shows that mouth contamination of ethanol diminished to insignificant levels after a few minutes. The detailed results of the analyses of nose‐exhaled breath show that the peak levels and the decay rates of breath ethanol are dependent on the ethanol dose and the volume of ethanol/water mixture ingested. From these data, both the efficiency of the first‐pass metabolism of ethanol and the indications of gastric emptying rates at the various doses and ingested volumes have been obtained for the two volunteers. Additionally and simultaneously, acetaldehyde, acetic acid and acetone were measured in each single breath exhalation. Acetaldehyde, the primary product of ethanol metabolism, is seen to track the breath ethanol. Acetic acid, a possible secondary product of this metabolism, was detected in the exhaled breath, but was shown to largely originate in the oral cavity. Breath acetone was seen to increase over the long period of measurement due to the depletion of nutrients. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
88.
89.
Olga I. Kalchenko Sergiy O. Cherenok Andriy V. Solovyov Vitaly I. Kalchenko 《Chromatographia》2009,70(5-6):717-721
The addition of calix[4]arenes to MeCN/H2O or MeOH/MeCN/THF/H2O mobile phases improves LC separation of benzene or uracil derivatives on Separon SGX C18 or Separon SGX NH2 supports. Structure of the calixarenes and their host–guest supramolecular complexes with the analytes are discussed in context of the LC separation. 相似文献
90.
Andriy Romanyuk Roland Steiner Daniel Mathys Verena Thommen Peter Oelhafen 《Surface science》2008,602(9):L49-L52
In this letter, we report on the use of tin as an effective surfactant material for silver growing on silicon oxide. We observed that submonolayers of Sn pre-deposited on SiO2 result in earlier film coalescence and formation of smoother Ag layers. We suggest that Sn atoms reduce the Ag-adatom mobility resulting in experimentally observed increased island density and decreased film roughness. Angle-resolved X-ray photoelectron spectroscopy reveals that Sn remains under the Ag layer giving circumstantial evidence that at later stages of Ag film growth Sn does not influence the interlayer transport. 相似文献