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81.
Nikolay A. Brusentsov Tatiana N. Brusentsova Elena Yu. Filinova Nikolay Y. Jurchenko Dmitry A. Kupriyanov Yuri A. Pirogov Andry I. Dubina Maxim N. Shumskikh Leonid I. Shumakov Ekaterina N. Anashkina Alexandr A. Shevelev Andry A. Uchevatkin 《Journal of magnetism and magnetic materials》2007
A dextran-ferrite magnetic fluid was successfully tested as magnetic resonance imaging (MRI) contrast agent. The same magnetic fluid was then combined with Melphalan, a chemotherapeutic drug, and used for magnetohydrodynamic thermochemotherapy of different tumors. The placement of the tumors in an AC magnetic field led to hyperthermia at 46 °C for 30 min. In combination with tumor slime aspiration, a 30% regression of ∼130 mm3 non-metastatic P388 tumors in BDF1 mice was reached, together with a life span increase of 290%. The same procedure associated with cyclophosphamide treatment of ∼500 mm3 metastases tumor increased the animal's life span by 180%. 相似文献
82.
Rustem R. Amirov Asiya R. Mustafina Zuleikha T. Nugaeva Svetlana V. Fedorenko Ella Kh. Kazakova Alexandr I. Konovalov Wolf D. Habicher 《Journal of inclusion phenomena and macrocyclic chemistry》2004,49(3-4):203-209
The stoichiometry and binding constant of the paramagnetic lanthanide ion(Gd3+) with sulfonatomethylated calix[4]resorcinarene (H8Xna4) were evaluated from the NMR relaxation data. Both 1H NMR spectroscopy and NMR relaxation data indicate that interaction of tetramethylammonium (TEMA) and N-methylpyridinium (MePy) cations with H8Xna4 in the presence of Ln3+ (Lu3+ or Gd3+) results in theformation of ternary complexes [Ln(G)H8X] with lanthanide ions,coordinated via sulfonate groups and organic cation included intothe cavity of H8Xna4. The inclusion of long-chainedN-decyl-(DePy) and N-cetylpyridinium (CPy) ions into H8Xna4 cavity leads to self-assembling which can be revealed by NMR relaxation method with Gd3+ probe ions. The excess of alkylpyridinium or TEMA cations leads to disassembling of (Gd)n(H8X)m(RPy)maggregates. 相似文献
83.
Vadim A. Bataev Eugeniy K. Dolgov Alexandr V. Abramenkov Vladimir I. Pupyshev Igor A. Godunov 《International journal of quantum chemistry》2002,88(4):414-425
The potential energy surface (PES) for the CHF2CHO molecule in the excited S1 state is calculated by the CASSCF method. The features of the 1‐ and 2‐D cross‐sections of PES are considered in comparison with those of the relative molecules. The vibrational frequencies are calculated in harmonic approximation and the vibrational energy levels for the inversion motion of the carbonyl fragment CCHaO and for the torsion motion of the CHF2‐top are calculated in anharmonic approximation by the 1‐ and 2‐D variational methods. The calculated data are compared with the experimental ones. The problems of the experimental data interpretation are considered. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002 相似文献
84.
A simple, single-step derivatization technique is presented for capillary GC-FID and GC-MS separation and identification of common protein and non-protein constituents of natural peptides as their tert-butyldimethylsilyl (TBDMS) derivatives. The tert-butyldimethyl-silylation of more than sixty compounds was accomplished with high yields and a single peak observed for each component. The TBDMS derivatives of both the protein and non-protein substances, moreover, exhibit excellent separation on apolar capillary columns and can be resolved completely using a polydimethylsiloxane or 5 % phenyl polydimethylsiloxane column and, complementarily, a 50 % phenyl polydimethylsiloxane column. Retention data and molar responses of the TBDMS derivatives on the polydimethylsiloxane column are compiled. Direct coupling of the 5 % phenyl polydimethylsiloxane column to an ion trap mass spectrometer enabled fast separation and identification of the investigated components, at nanomole to picomole levels, on the basis of retention and mass spectral data. The general usefulness of the method is demonstrated by research into new biologically active peptides isolated from entomopathogenic fungi. 相似文献
85.
Talyzin AV Tsybin YO Peera AA Schaub TM Marshall AG Sundqvist B Mauron P Züttel A Billups WE 《The journal of physical chemistry. B》2005,109(12):5403-5405
Prolonged hydrogenation of C(60) molecules by reaction with H(2) at elevated temperature and pressure results in fragmentation and collapse of the fullerene cage structure. However, fragments can be preserved by immediate termination of dangling bonds by hydrogen. Here we demonstrate that not only fullerene fragments but also hydrogenated fragmented fullerenes (e.g., C(58)H(40) and C(59)H(40)) can be synthesized in bulk amount by high-temperature hydrogenation of C(60). We confirm successful synthesis of these species by matrix-assisted laser desorption ionization time-of-flight mass spectrometry and complete speciation of the resultant complex fullerene mixtures by high-resolution field desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry. 相似文献
86.
Kuzma M Jegorov A Hesso A Tornaeus J Sedmera P Havlícek V 《Journal of mass spectrometry : JMS》2002,37(3):292-298
The product ion mass spectra (collisionally induced dissociation mass spectra) of 12 different cyclosporins modified at every N-methylated amino acid residue with respect to cyclosporin A were compared and the effect of N-demethylation on ring opening mechanisms was evaluated. The four preferential protonation sites were identified in [MeBmt(1)]-cyclosporins. Three sites represented the N-methylated nitrogens of Sar(3), MeLeu(6) and MeLeu(9), while the remaining one represented the lactone group formed by the intramolecular N,O-acyl shift. Selective N-demethylation resulted either in the deletion of the entire fragment ion series or its substantial attenuation. The structures of three new natural cyclosporins in the study were supported by NMR data. 相似文献
87.
Albina Y. Ziganshina Sergey V. Kharlamov Dmitry E. Korshin Rezeda K. Mukhitova Ella Kh. Kazakova Shamil K. Latypov Vitaly V. Yanilkin Alexandr I. Konovalov 《Tetrahedron letters》2008,49(36):5312-5315
A new molecular capsule based on viologen-resorcinarene and sulfonatomethylene-resorcinarene is synthesized and its redox-controlled stability is investigated. 相似文献
88.
Ekaterina V. Shevaldina Ksenia A. Opredelennova Olga A. Chichvarina Yury Ya. Spiridonov Alexandr F. Smol'yakov Pavel V. Dorovatovskii Sergey K. Moiseev 《应用有机金属化学》2019,33(11)
α‐Ferrocenylalkylation of azoles or S‐nucleophiles with FcCH(R)OH (Fc = ferrocenyl) can be accomplished under acid‐free conditions as one‐pot process via an intermediate formation of the α‐ferrocenylalkyl carbonates FcCH(R)OC(O)OEt. The reaction allows the alkylation of acid sensitive substrates like imidazole derivatives or sodium N,N‐diethyldithiocarbamate. The reaction with ambident azoles proceeds as the N‐alkylation. Some α‐ferrocenylalkyl azoles were found to exhibit plant growth stimulating or herbicidal effects on corn seeds or act as the herbicide safeners against sulfonylurea herbicides. 相似文献
89.
Dr. Jinhua Sun Artem Iakunkov Dr. Igor A. Baburin Boby Joseph Prof. Vincenzo Palermo Dr. Alexandr V. Talyzin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(3):1103-1108
COF-1 has a structure with rigid 2D layers composed of benzene and B3O3 rings and weak van der Waals bonding between the layers. The as-synthesized COF-1 structure contains pores occupied by solvent molecules. A high surface area empty-pore structure is obtained after vacuum annealing. High-pressure XRD and Raman experiments with mesitylene-filled (COF-1-M) and empty-pore COF-1 demonstrate partial amorphization and collapse of the framework structure above 12–15 GPa. The ambient pressure structure of COF-1-M can be reversibly recovered after compression up to 10–15 GPa. Remarkable stability of highly porous COF-1 structure at pressures at least up to 10 GPa is found even for the empty-pore structure. The bulk modulus of the COF-1 structure (11.2(5) GPa) and linear incompressibilities (k[100]=111(5) GPa, k[001]=15.0(5) GPa) were evaluated from the analysis of XRD data and cross-checked against first-principles calculations. 相似文献
90.
We present a generalization of the concept of semiholonomic jets within the framework of higher order prolongations of a fibred manifold. In this respect, a compilation of our 2-fibred manifold approach with the methods of natural operators theory is used. 相似文献