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51.
52.
Artificial and highly selective antibodies (in the form of gel granules) against proteins can easily be synthesized by a simple, cost-effective imprinting technique [Liao, J.-L. et al., Chromatographia 1996, 42, 259-262]. Using the same method for synthesis of gel antibodies against viruses in combination with analysis by free zone electrophoresis in a rotating narrow bore tube we have shown that artificial gel antibodies against Semliki Forest Virus (wild type) can sense the difference between this virus and a mutant, although they differ in their chemical composition only by three amino acids in one of the three proteins on the surface of the virus particle. The reason for this extremely high resolution is explained by the fact that we use three types of selectivity: (i) shape selectivity (created by the close fit between the antigen and its imprint in the gel), (ii) bond selectivity in the contact area between the antigen and its imprint in the gel antibody, and (iii) charge selectivity, originating from slightly different structures or/and conformations of the antigens. 相似文献
53.
Ferenc Fülp Enik Forr Gbor Bernth Istvn Miskolczi Pirjo Vainiotalo Aarne Martinsen 《Journal of heterocyclic chemistry》1997,34(1):289-293
The Hammett-Brown electrophilic substituent constants σ+ for five heteroaryl-substituted phenyl groups were estimated via the ring-chain tautomeric equilibria of three sets of oxazolidines and 1,3-oxazines in deuteriochloroform solution. For oxazolidines derived from norephedrine and norpseudoephedrine, the σ+ values were also determined via the gas-phase ring-chain equilibria, by means of mass spectrometry. The results show that the heteroaromatic substituents studied have a slight electron-withdrawing character, with σ+ in the range -0.03 to 0.59. The gas-phase σ+ values are significantly higher than the solution values. 相似文献
54.
The excess volumes of mixing for methanol and ethanol with secondary amines (diethylamine, di-n-propylamine and di-n-butylamine) have been measured over the whole composition range at 293.15 and 323.15 K. The excess volumes have been fitted to an equation of the type $$V^E /cm^3 mol^{--1} = x \left( {1 - x} \right) \sum\limits_{n = 0}^3 { A_n \left( {1 - 2x} \right)^n } $$ The different temperature dependences of the mixtures were explained by means of the association theory. 相似文献
55.
Bla Ivn Joseph P. Kennedy Tibor Kelen Ferenc Tüdos 《Journal of polymer science. Part A, Polymer chemistry》1981,19(3):679-685
Colorless poly(vinyl chloride)s (PVC) containing up to 1.6 allylic chlorines per molecule have been prepared by controlled random dehydrochlorination with a strong base. The effect of temperature in the ?50 to +24°C range on the number of allylic chlorines and color of PVC has been investigated by ozonization experiments and UV–visible spectroscopy. A two-parameter kinetic model has been developed which quantitatively accounts for the observations and points the way for further research. 相似文献
56.
We investigate the regular and moving Liesegang pattern formation phenomena in an open system. First, simulations have been performed at fixed coupling between the reactive medium and the reservoir, later this control parameter was varied during the simulations resulting in various phenomena. We predicted and monitored for the first time various--dynamically changing--precipitation structures and a spatial hysteresis phenomenon, which is beyond the scope of the Turing instability. The dynamics of the reaction is well detectable using specific quantities: the total amount of precipitate and its center of gravity. 相似文献
57.
István Ilisz Zoltán Pataj Róbert Berkecz Aleksandra Misicka Dagmara Tymecka Ferenc Fülöp Hee Jung Choi Myung Ho Hyun Antal Péter 《Journal of chromatography. A》2010,1217(7):1075-1082
Reversed-phase high-performance liquid chromatographic methods were developed for the separation of enantiomers of eleven unnatural β2-amino acids on a new chiral stationary phase, using the 11-methylene-unit spacer of aminoundecylsilica gel for the bonding of (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid as selector. The nature and concentration of the acidic and organic modifiers, the pH, the mobile phase composition, and the structures of the analytes substantially influenced the retention and resolution. Separations were carried out at constant mobile phase compositions in the temperature range 7–40 °C and the changes in enthalpy, Δ(ΔH°), entropy, Δ(ΔS°), and free energy, Δ(ΔG°) were calculated. The elution sequence was determined in some cases: the S enantiomers eluted before the R enantiomers. 相似文献
58.
Jnos Madarsz Petra Bombicz Czugler Mtys Ferenc Rti Gbor Kiss Gyrgy Pokol 《Thermochimica Acta》2009,490(1-2):51-59
Detailed study on identification and thermal decomposition of solid title compounds 1 and 2 crystallized from the used aqueous ammonia solutions of Pd(NH3)2(NO2)2 and Pt(NH3)2(NO2)2, has been carried out. Beyond the composition of complexes 1 and 2, their trans square planar configuration have already been recognized by reference IR spectra and powder XRD patterns, nevertheless their exact molecular and crystal structure as of trans-Pd(NH3)2(NO2)2 (1, Pd-NN) and trans-Pt(NH3)2(NO2)2 (2, Pt-NN) has been determined by single crystal X-ray diffraction (R = 0.0515 and 0.0341), respectively. Despite their compositional and configuration analogy, they crystallize in different crystal systems and space groups. The crystals of 1 (Pd-NN) are triclinic (space group No. 2, P-1, a = 5.003(1) Å, b = 5.419(1) Å, c = 6.317(1) Å, α = 91.34(2)°, β = 111.890(10)°, γ = 100.380(10)°), while those of 2 (Pt-NN) are monoclinic (space group No. 5, C2, a = 7.4235(16) Å, b = 9.130(2) Å, c = 4.4847(10) Å, β = 99.405(7)°).The pyrolytic processes of 1 and 2 (which might be sensitive to shock and heat) have been followed by simultaneous thermogravimetric and differential thermal analysis (TG/DTA), while the evolved gaseous species have been traced in situ by online coupled TG/DTA–EGA–MS and TG–EGA–FTIR instruments in He and air. Pd and Pt powders, forming as final solid products in single step, are captured and checked by TG and XRD. Whilst the unified evolved gas analyses report evolution of N2, H2O, NH3, N2O, NO, and NO2 gases as gaseous product components in the exothermic decomposition of both trans-Pd(NH3)2(NO2)2 (1) and trans-Pt(NH3)2(NO2)2 (2) starting from ca. 230 and 220 °C, in sealed crucibles with a pinhole on the top, respectively. 相似文献
59.
Dr. Matteo P. Placidi Prof. Dr. Mauro Botta Dr. Ferenc K. Kálmán Dr. Gisela E. Hagberg Dr. Zsolt Baranyai Andreas Krenzer Alexandria K. Rogerson Prof. Dr. Imre Tóth Prof. Dr. Nikos K. Logothetis Priv.‐Doz. Dr. Goran Angelovski 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(35):11644-11660
A series of low molecular weight lanthanide complexes were developed that have high 1H longitudinal relaxivities (r1) and the potential to be used as dual frequency 1H and 19F MR probes. Their behavior was investigated in more detail through relaxometry, pH‐potentiometry, luminescence, and multinuclear NMR spectroscopy. Fitting of the 1H NMRD and 17O NMR profiles demonstrated a very short water residence lifetime (<10 ns) and an appreciable second sphere effect. At lower field strengths (20 MHz), two of the complexes displayed a peak in r1 (21.7 and 16.3 mM ?1 s?1) caused by an agglomeration, that can be disrupted through the addition of phosphate anions. NMR spectroscopy revealed that at least two species are present in solution interconverting through an intramolecular binding process. Two complexes provided a suitable signal in 19F NMR spectroscopy and through the selection of optimized imaging parameters, phantom images were obtained in a MRI scanner at concentrations as low as 1 mM . The developed probes could be visualized through both 1H and 19F MRI, showing their capability to function as dual frequency MRI contrast agents. 相似文献
60.
Lajos Simon S. Gizella Talpas Ferenc Fülp Gbor Bernth Gyula Argay Alajos Klmn PL Sohr 《Journal of heterocyclic chemistry》1995,32(1):161-167
trans-Perhydro-1,4-benzoxazepin-3-ones 2a-c were synthesized and transformed to condensed-skeleton perhydro-trans-1,4-benzoxazepines 3a,b , the thiones 4a,b , the urea derivatives 5a,b , and N-acylated compounds 6a-e . Compounds 6b,d were ring-opened by hydrochloric acid in ethanol to yield trans-2-(1-carbethoxyethoxy)-1-acylaminomethylcyclohexane derivatives 7b,d . The 1H- and 13C-nmr investigation and X-ray analysis of 5b and 6c,d proved that the expected N-acylated derivatives were formed and that both rings of the trans anellated compounds have a chair conformation. 相似文献