Report No xxxx - Instytut Fizyki JÄdrowej PAN

More documents

Recommendations

Info

To obtain model derivatives, prepared compound was used in the nucleophilic substitution reaction with several amino acids. It appeared that the course of the reaction has been strongly affected by the conditions applied (Scheme 3) leading to N-phenyl substituted amino acids or to benzoimidazole derivarives. It was found that in both cases the differences in fluorine chemical shifts for different amino acids are large enough to use new marker in discussed investigations (Table 1). O N 2 Cl CF 3 + R CH COOH H 2 O NaHCO 3 HOOC O 2 N CH NH R CF 3 SO 3 Na NH 2 SO 3 Na (1) Cl O N CF 2 3 + R CH COOH NH SO Na 2 3 H 2 O NaHCO 3 NaO S 3 CF 3 N N ONa R (2) Scheme 3 Aminoacid Ala Gab Ser Phe Glh Tyr Thr Ile Leu Val 1 derivs. 17.05 17.15 17.56 17.72 17.79 17.84 17.86 17.78 17.97 18.25 2 derivs. 16.39 16.64 16.54 16.51 16.36 16.53 16.57 16.50 16.59 16.42 Table 1 84
MOLECULAR DYNAMICS OF TERT-BUTYL CHLORIDE CONFINED TO CPG (7.4 NM) Lidia Szutkowska, Barbara Peplińska, Stefan Jurga Institute of Physics, A. Mickiewicz University, ul. Umultowska 85, 61-614 Poznań, Poland The paper reports the proton and deuteron NMR study of molecular dynamics of tertbutyl chloride confined in CPG with pore diameter of 7.4 nm here denoted as TBCC. The 1 H and 2 H NMR lineshapes and spin-lattice relaxation times were measured in the temperature range 70 K ≤ T ≤ 292 K, thus covering all the phases which occur in the bulk state of TBC. The phase transition from liquid to solid phase I of the TBCC is invisible in temperature dependences of 1 H and 2 H spin-lattice relaxation times. The temperatures of the other phase transitions of TBCC are depressed, by about 23 K in comparison with bulk TBC. The values of 1 H, 2 H relaxation times T 1 are reduced indicating that the confinement strongly restricts molecular reorientation. Two exponential magnetization recoveries are observed in the temperature range corresponding to the solid phase II and III. The dynamical behaviour of the TBCC can be explained by assuming that the guest molecules form two distinct phases: the surface-affected phase, composed of molecules located at the pore surface, and the bulk-like phase located at the center of the pores. The relative amount of the surface-affected phase is significantly larger than the bulk-like phase compared to the results obtained for larger pore diameters of CPG [1- 3]. In phase III, the temperature dependences of 1 H and 2 H spin-lattice relaxation times of the bulk-like component of TBCC exhibit higher, shallower and wider minimum. This is attributed to the coexistence of subphases with different correlation times characterizing rotation of the tert-butyl group, as the consequence of confinement. The calculated activation energies and preexponential factors for C ’ 3 rotation in two dynamically different states of bulk-like phase obtained from both 1 H and 2 H T 1 data are given in Table I. The fact that the energies of the tert-butyl reorientation are much lower than in bulk TBC and lower than for TBCC with larger pore diameters [2,3], may result from a decrease of the intermolecular interactions in the bulk liquid phase of TBCC. This effect can be explained by the surface to volume ratio, increasing with the reduction of the pore diameters, where a large fraction of confining molecules experiences direct interaction with pore walls. The slowing down of the motion can be also due to geometrical restrictions and depends on the degree of reductio n of the pore siz e. ’ Table 1. Activation energies and the preexponential factors of the C 3 confined to 7.4 nm pore diameters CPG obtained from 1 H, 2 H T 1 . motion of bulk-like phase of TBC Subphase I Subphase II TBC in bulk [2] 1 H T 1 2 H T 1 E a (kJ/mol) 4.2 4.6 τ 0 (s) 1.4 E-11 2.2E-11 E a (kJ/mol) 4.2 4.6 τ 0 (s) 1E-10 1E-10 E a (kJ/mol) 15.5 τ 0 (s) 1E-14 1. L. Wasyluk, B. Peplinska, J. Klinowski, and S. Jurga, Phys. Chem. Chem. Phys. 4, 2392 (2002). 2. L. Wasyluk, B. Peplinska, S. Jurga, Solid State NMR 25, Iss.1-3, 2004 (in press) 3. L. Wasyluk, B. Peplinska, S. Jurga, Abstracts, XX International Seminar RAMIS 2003, P-68 85
Page 1 and 2:
The Henryk Niewodniczański INSTITU
Page 3 and 4:
Contents R. Banyś, A. Słowik, M.
Page 5 and 6:
J. Kolmas, M. Uniczko, E. Kalinowsk
Page 7 and 8:
Ł. Popenda, Z. Gdaniec, G. Dominia
Page 9 and 10:
USEFULNESS OF PROTON MAGNETIC RESON
Page 11 and 12:
INFLUENCE OF PARAMAGNETIC IONS ON F
Page 13 and 14:
NMR RELAXATION OF PAPER SAMPLES Bar
Page 15 and 16:
SPIN-LATTICE RELAXATION OF D 2 QUAN
Page 17 and 18:
INVESTIGATION OF NEUROPROTECTING EF
Page 19 and 20:
OPTICAL PUMPING OF 3 He Katarzyna C
Page 21 and 22:
NMR STUDY OF GELATION PROCESS OF LO
Page 23 and 24:
MRI INVESTIGATIONS OF HYDROGEL FORM
Page 25 and 26:
CHEMICAL SHIFT TITRATION AT THE INT
Page 27 and 28:
LOCAL DYNAMICS AND ORGANIZATION OF
Page 29 and 30:
1 H NMR DETECTION OF σ-ADDUCTS IN
Page 31 and 32:
HYDRATION OF WHEAT PHOTOSYNTHETIC M
Page 33 and 34: References: 1. H. Harańczyk On wat
Page 35 and 36: (EDV) and end-systolic (ESV) volume
Page 37 and 38: THE MOST STABLE POLYMORPHIC FORM OF
Page 39 and 40: A DETERMINATION OF ABSOLUTE SHIELDI
Page 41 and 42: DIAGNOTIC VALUE OF MRI IN CONVERSIO
Page 43 and 44: NMR AND FTIR STUDY OF MOLECULAR DYN
Page 45 and 46: EFFECTS OF INTERMOLECULAR INTERACTI
Page 47 and 48: 600000 Integral of 1D MRI profils [
Page 49 and 50: simultaneous analyse of the tempera
Page 51 and 52: 1 H NMR STUDIES OF PLATINUM(II) CHL
Page 53 and 54: 35 Cl-NQR STUDY OF ELECTRONIC STRUC
Page 55 and 56: 35 Cl- NQR AND 1 H-NMR STUDY OF MOL
Page 57 and 58: THE SYNTHESIS AND NMR ANALYSIS OF T
Page 59 and 60: STUDY OF MOTIONAL PROCESSES OF DRAW
Page 61 and 62: intensity (arb. units) 0,20 0,15 0,
Page 63 and 64: data for Cβ-nonplanar model 3 are
Page 65 and 66: T 1 DISPERSION AND SELF-DIFFUSION N
Page 67 and 68: A LOW FIELD MRI SYSTEM FOR HYPERPOL
Page 69 and 70: 1 H MAS NMR OF FLAVONOIDS Katarzyna
Page 71 and 72: EFFECT OF TEMPERATURE ON LIPOSOME S
Page 73 and 74: 1 H, 13 C NMR AND GIAO/DFT CALCULAT
Page 75 and 76: NMR STUDY OF THE HUMIC ACIDS EXTRAC
Page 77 and 78: NMR STUDY OF LAYERED ANGANITE La 1.
Page 79 and 80: MAGNETIC SUSCEPTIBILITY EVALUATION
Page 81 and 82: A NOVEL SOURCE OF MAGNETIC FIELD FO
Page 83: DETERMINATION OF AMINO ACIDS IN BOD
Page 87 and 88: MR MICROSCOPY IN COMPARISON OF YOUN
Page 89 and 90: NH CH CH 2 NH CH CO COONa n CH 2 m
Page 91 and 92: 35 Cl-NQR STUDY OF MOLECULAR DYNAMI
Page 93 and 94: 35 Cl-NQR STUDY OF THE SUBSTITUENT
Page 95 and 96: 13 C AND 1 H NUCLEAR MAGNETIC SHIEL
Page 97 and 98: 13 C CPMAS NMR OF ANTHOCYANINS AND
Page 99 and 100: INVESTIGATION OF TRANSESTERIFICATIO
Page 101 and 102: T 2 RELAXATION MAP OF ARTICULAR CAR
Page 103 and 104: MICROTOMOGRAPHY STUDIES OF TABLETS
Page 105 and 106: MAPPING OF THE BI-EXPONENTIAL DIFFU
Page 107 and 108: DEUTERIUM NMR IN RMn 2 D 2 (R = Y,
Page 109 and 110: The neutron scattering (IINS, QNS,
Page 111 and 112: STRUCTURE OF 4-QUINOLINONES ANALYSE
Page 113: NMR MULTIPOLE RELAXATION IN THE ROT
show all

Report No xxxx - Instytut Fizyki JÄ drowej PAN

Create successful ePaper yourself

Delete template?

Save as template?

Report No xxxx - Instytut Fizyki JÄdrowej PAN