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Thermal Parameters (thermal + parameter)
Selected AbstractsStudies on multiphased mixed crystals of NaCl, KCl and KICRYSTAL RESEARCH AND TECHNOLOGY, Issue 1 2009M. Priya Abstract Multiphased mixed crystals of NaCl, KCl and KI were grown by the melt method, for the first time. Densities and refractive indices of all the grown crystals were determined and used for the estimation of the composition in the crystal. Atomic absorption spectroscopic measurements were done to estimate the metal atom contents in the crystal. Lattice parameters and thermal parameters (Debye-Waller factor, mean square amplitude of vibration, Debye temperature and Debye frequency) were determined from the X-ray powder diffraction data. DC and AC electrical measurements were done at various temperatures ranging from 40 to 150°C. Activation energies were also estimated. The observed lattice parameters showed that the system exhibits three phases each nearly corresponds to NaCl, KCl and KI. The thermal and electrical parameters show a highly nonlinear bulk composition dependence. Results are reported. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Synthesis and crystal structure determination of 6,7-dihydro-2-methoxy-4-(substituted)-5H -benzo[6,7]cyclohepta[1,2- b ]pyridine-3-carbonitrileCRYSTAL RESEARCH AND TECHNOLOGY, Issue 4 2007A. M. Moustafa Abstract The compounds 6,7-dihydro-2-methoxy-4-(4-methylphenyl)-5H -benzo[6.7]cyclohepta[1,2 -b ]pyridine-3-carbonitrile (compound IIIa) and 4-(4-chlorophenyl)-6,7-dihydro-2-methoxy-5H -benzo[6,7]cyclohepta[1,2- b ]pyridine-3-carbonitrile (compound IIIb) were synthesized and their structures have been determined from three dimensional X-ray data using direct method and refined by full matrix least squares with anisotropic thermal parameters for non-hydrogen atoms to conventional R(gt) of 0.036 and 0.038 for the two compounds respectively. For compound (IIIa) the crystals are monoclinic, space group Cc, with a=11.2909 (5) Å, b=17.7755(8) Å, c=9.1437(4) Å and ,=95.428(3)°, while the crystals of the second compound (IIIb) are triclinic, space group P1, with a=8.7465(3)Å, b=10.3958(3)Å, c=10.9011(4)Å, ,= 108.3870(10)°, ,=101.3741(12)°, ,=97.9594(12)°. The molecular structure of the two compounds have nearly the same configuration, where the cyclohepta ring takes the boat shape and the methoxy and the carbonitrile groups are attached at the same position C2 and C8. The difference occurs only at the position C4, where the substituent is methylphenyl for compound (IIIa) and chlorophenyl for the other. The bond lengths, valency angles and the hydrogen bonding were calculated and fully discussed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] A simulation of the hydrothermal response to the Chesapeake Bay bolide impactGEOFLUIDS (ELECTRONIC), Issue 3 2005W. E. SANFORD Abstract Groundwater more saline than seawater has been discovered in the tsunami breccia of the Chesapeake Bay Impact Crater. One hypothesis for the origin of this brine is that it may be a liquid residual following steam separation in a hydrothermal system that evolved following the impact. Initial scoping calculations have demonstrated that it is feasible such a residual brine could have remained in the crater for the 35 million years since impact. Numerical simulations have been conducted using the code HYDROTHERM to test whether or not conditions were suitable in the millennia following the impact for the development of a steam phase in the hydrothermal system. Hydraulic and thermal parameters were estimated for the bedrock underlying the crater and the tsunami breccia that fills the crater. Simulations at three different breccia permeabilities suggest that the type of hydrothermal system that might have developed would have been very sensitive to the permeability. A relatively low breccia permeability (1 × 10,16 m2) results in a system partitioned into a shallow water phase and a deeper superheated steam phase. A moderate breccia permeability (1 × 10,15 m2) results in a system with regionally extensive multiphase conditions. A relatively high breccia permeability (1 × 10,14 m2) results in a system dominated by warm-water convection cells. The permeability of the crater breccia could have had any of these values at given depths and times during the hydrothermal system evolution as the sediments compacted. The simulations were not able to take into account transient permeability conditions, or equations of state that account for the salt content of seawater. Results suggest, however, that it is likely that steam conditions existed at some time in the system following impact, providing additional evidence that is consistent with a hydrothermal origin for the crater brine. [source] ROCK-SURFACE TEMPERATURES OF BASALT IN THE DRAKENSBERG ALPINE ENVIRONMENT, LESOTHOGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2007STEFAN GRAB ABSTRACT. Rock temperature data are presented for a variety of topographic localities at a high Drakensberg site. The objective is to investigate the spatiotemporal variations of surface rock temperatures in high Drakensberg basalt. The temperature results are then used to discuss possible implications for thermal stress fatigue and frost-induced weathering. TinytalkÔ data loggers and probes were used for rock-surface temperature recording. Long-term measurements were recorded over 12 months from May 2002 to April 2003, at a 1-hour logging interval and rock depth of 1 cm for a highaltitude (3300 m a.s.l.) interfluve and fracture site. Whilst the north-facing rock surface experiences negligible hours below ,3°C, the south-facing rock surface and interfluve sites are subjected to considerable periods below ,3°C, which falls within the ,frost cracking window'. It is concluded that the substantial contrasts of recorded rock thermal parameters over small spatial scales between various topographic settings, highlight that site-specific measurements across the broader scale are required for an adequate evaluation of regional weathering and its associated landform development. [source] Temperature and Thermal Balance Monitoring and Control in DialysisHEMODIALYSIS INTERNATIONAL, Issue 2 2003Franti, ek Lopot Temperature and thermal balance have been studied in an effort to explain better tolerance of ultrafiltration during isolated ultrafiltration and other convective techniques as compared to conventional hemodialysis. The large number of published studies has led to the conclusion that negative thermal balance of the extracorporeal circuit ameliorates hemodynamic stability by increased vasoreactivity and increased peripheral resistance. On the other hand, measurement of dialysis efficiency (urea removal) did not unequivocally confirm the theoretically predicted decrease in efficiency of "cool" dialysis. Another suggested application of temperature and thermal balance for assessing bioincompatibility is currently hampered by the ability of existing technology to evaluate thermal parameters of the extracorporeal circuit only. Publications on impact of negative thermal balance of the extracorporeal circuit on ultrafiltration-induced changes in blood volume give contradictory results. Further studies are needed for elucidation of the impact of thermal balance on overall biological response to dialysis. [source] The influence of thermal parameters on the acclimation responses of pinfish Lagodon rhomboides exposed to static and decreasing low temperaturesJOURNAL OF FISH BIOLOGY, Issue 3 2007C. M. Reber Pinfish Lagodon rhomboides acclimation rates were determined by modelling changes in critical thermal minimum (Tcrit min, ° C) estimates at set intervals following a temperature decrease of 3,4° C. The results showed that pinfish gained a total of 3·7° C of cold tolerance over a range of acclimation temperatures (Tacc, ° C) from (23,12° C), that cold tolerance increased with exposure time to the reduced temperature at all Tacc, but that the rate of cold tolerance accruement (mean 0·14° C day,1) was independent of Tacc. A highly significant (P < 0·001) multivariate predictive model was generated that described the acclimation rates and thermal tolerance of pinfish exposed to reduction in water temperature: log10Tcrit min= 0·41597 , 0·01704Tacc+ 0·04320Tplunge, 0·08376[log10 (t+ 1)], where Tplunge is plunge temperature (° C) and t is the time (days). A comparison of the present data, with acclimation rate data for other species, suggests that factors such as latitude or geographic range may play a more important role than ambient temperature in determining cold acclimation rates in fishes. [source] ELECTRICAL CONDUCTIVITY OF HEATED CORNSTARCH,WATER MIXTURESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 6 2009EDUARDO MORALES-SANCHEZ ABSTRACT Electrical conductivity (EC) of cornstarch,water mixtures in the range 10:90 to 70:30 (w/w) was studied as a function of temperature. An external resistive heating system equipped with an electronic device capable of monitoring EC in real time was used and EC of the mixtures was measured while heated at a rate of 5C/min. Results showed that EC went through four different temperature-dependent stages (A, B, C and D). Stage B (41C to 64C) showed a lower EC increasing rate when compared with that of Stage A (from 25C to 41C), probably as a result of starch granule swelling. In Stage C (64C to 78C), EC behavior was found to be dependent on water content. When water content was more than 50%, the value for EC increased. On the other side, EC decreased when water content was less than 50%. Stage C was related to starch gelatinization, according to differential scanning calorimetry results obtained in this study. In Stage D (78C to 92C), a steady increase in EC was observed, probably as a result of the total solubilization of starch in water. It was concluded that Stage C in EC graphs corresponded to cornstarch gelatinization, so it might be possible to use EC monitoring as an alternative technique to measure cornstarch thermal characteristics with different contents of water. PRACTICAL APPLICATIONS Electrical conductivity can be used as an adequate technique to monitor gelatinization, granule swelling and phase change of starch as a function of temperature in corn starch,water mixtures with a wide range of water contents. With this technique, it is also possible to calculate important thermal parameters, such as the beginning and end of the gelatinization and the energy activation for the heating process of cornstarch. This can lead to a better design and control of important industrial corn processes such as alkaline cooking. [source] PREDICTING TEXTURE ATTRIBUTES FROM MICROSTRUCTURAL, RHEOLOGICAL AND THERMAL PROPERTIES OF HAZELNUT SPREADSJOURNAL OF TEXTURE STUDIES, Issue 5 2008ROSSELLA DI MONACO ABSTRACT Eight trained assessors evaluated one visual, eight texture and four gustative attributes of 15 commercial spreads. In addition, 100 consumers evaluated the acceptability of the spreads. Rheological behavior of the samples was evaluated in transient (stress,relaxation test) and dynamic (strain and frequency sweep test) shear mode. Thermal measurements were also performed. Finally, the microstructure of the samples was analyzed by scanning electron microscopy. Partial least squares regression was used to predict acceptability from sensory attributes and texture from instrumental data. Scanning electron micrographs indicated that spreads differed in morphology, size and distribution of hazelnut particles. Overall liking of the spreads was found to be related to hazelnut flavor and texture attributes. Prediction of the most important texture properties from instrumental measurements was quite successful, especially for spreadability which was found negatively related to the consistency and flow indices and, secondly, for meltability which was found to be strongly dependent on measured thermal parameters. PRACTICAL APPLICATIONS This study contributes to knowledge development in the research area of acceptability, sensory and instrumental correlation for semi-solid foods. The results confirm that texture properties of spreadable foods play a most important role in consumer acceptability. The research also allows better understanding as to why no single measurement is able to predict all texture attributes adequately and why more appropriate tests need to be developed for an accurate prediction of some sensory attributes as perceived by the human senses. [source] Simplified heat exchange model for semiconductor laser diodes thermal parameters extractionLASER PHYSICS LETTERS, Issue 11 2005P. S. André Abstract By investigating the heat flow mechanism in a semiconductor laser diode, we demonstrate a comprehensive technique for optical device thermal parameters extraction to be used in the prediction of the laser performance This accurate and precise heat exchange model takes into account the relevant heat exchange mechanism and mechanical considerations of the laser diode mounting. We measured the thermal response of a semiconductor laser diode attach to a substrate, deriving from those the device thermal parameters such as heat capacity and thermal conductance for the device and subtract. From the estimated values a prediction of the real laser temperature response is obtained directly from the measurements realized in the substrate. (© 2005 by Astro, Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source] Physical properties of rocks from the upper part of the Yaxcopoil-1 drill hole, Chicxulub craterMETEORITICS & PLANETARY SCIENCE, Issue 6 2004Y. Popov Thermal conductivity, thermal diffusivity, density, and porosity were measured on 120 dry and water-saturated rocks with a core sampling interval of 2,2.5 m. Nondestructive, non-contact optical scanning technology was used for thermal property measurements including thermal anisotropy and inhomogeneity. Supplementary petrophysical properties (acoustic velocities, formation resisitivity factor, internal surface, and hydraulic permeability) were determined on a selected subgroup of representative samples to derive correlations with the densely measured parameters, establishing estimated depth logs to provide calibration values for the interpretation of geophysical data. Significant short- and long-scale variations of porosity (1,37%) turned out to be the dominant factor influencing thermal, acoustic, and hydraulic properties of this post impact limestone formation. Correspondingly, large variations of thermal conductivity, thermal diffusivity, acoustic velocities, and hydraulic permeability were found. These variations of physical properties allow us to subdivide the formation into several zones. A combination of experimental data on thermal conductivity for dry and water-saturated rocks and a theoretical model of effective thermal conductivity for heterogeneous media have been used to calculate thermal conductivity of mineral skeleton and pore aspect ratio for every core under study. The results on thermal parameters are the necessary basis for the determination of heat flow density, demonstrating the necessity of dense sampling in the case of inhomogeneous rock formations. [source] Detection and climatology of fronts in a high-resolution model reanalysis over the AlpsMETEOROLOGICAL APPLICATIONS, Issue 1 2010J. Jenkner Abstract The identification of low-level thermal fronts is particularly challenging in high-resolution model fields over complex terrain. Firstly, direct model output often contains numerical noise which spuriously influences the high-frequency variability of thermal parameters. Secondly, the boundary layer interferes via convection and consequently leaves its thermal marks on low levels. Here, an automated objective method for the detection of frontal lines is introduced which is designed to be insusceptible to consequences of small grid spacings. To this end, existing algorithms are readopted and combined in a novel way. The overall technique subdivides into a basic detection of fronts and a supplemental division into local fronts and synoptic fronts. The fundamental parts of the detection are: (1) a smoothing of the initial fields, (2) a definition of the frontal strength, and, (3) a localisation with the thermal front parameter. The local fronts are identified by means of a classification of open and closed thermal contours. The resulting data comprise the spatial outline of the frontal structures in a binary field as well as their type and movement. The novel methodology is applied to a 3 year high-resolution reanalysis over central Europe computed with the COSMO model using a grid spacing of 7 km. Grid-point based climatologies are derived for the Alpine region. Frequencies of occurrence and characteristics of motion are analysed for different frontal types. The novel climatology also provides quantitative evidence of dynamical properties such as the retardation of cold fronts ahead of mountains and the dissolution of warm fronts over mountains. Copyright © 2009 Royal Meteorological Society [source] Multipole electron-density modelling of synchrotron powder diffraction data: the case of diamondACTA CRYSTALLOGRAPHICA SECTION A, Issue 4 2010H. Svendsen Accurate structure factors are extracted from synchrotron powder diffraction data measured on crystalline diamond based on a novel multipole model division of overlapping reflection intensities. The approach limits the spherical-atom bias in structure factors extracted from overlapping powder data using conventional spherical-atom Rietveld refinement. The structure factors are subsequently used for multipole electron-density modelling, and both the structure factors and the derived density are compared with results from ab initio theoretical calculations. Overall, excellent agreement is obtained between experiment and theory, and the study therefore demonstrates that synchrotron powder diffraction can indeed provide accurate structure-factor values based on data measured in minutes with limited sample preparation. Thus, potential systematic errors such as extinction and twinning commonly encountered in single-crystal studies of small-unit-cell inorganic structures can be overcome with synchrotron powder diffraction. It is shown that the standard Hansen,Coppens multipole model is not flexible enough to fit the static theoretical structure factors, whereas fitting of thermally smeared structure factors has much lower residuals. If thermally smeared structure factors (experimental or theoretical) are fitted with a slightly wrong radial model (s2p2 instead of sp3) the radial scaling parameters (`,' parameters) are found to be inadequate and the `error' is absorbed into the atomic displacement parameter. This directly exposes a correlation between electron density and thermal parameters even for a light atom such as carbon, and it also underlines that in organic systems proper deconvolution of thermal motion is important for obtaining correct static electron densities. [source] On the application of an experimental multipolar pseudo-atom library for accurate refinement of small-molecule and protein crystal structuresACTA CRYSTALLOGRAPHICA SECTION A, Issue 2 2007Bartosz Zarychta With an increasing number of biomacromolecular crystal structures being measured to ultra-high resolution, it has become possible to extend to large systems experimental charge-density methods that are usually applied to small molecules. A library has been built of average multipole populations describing the electron density of chemical groups in all 20 amino acids found in proteins. The library uses the Hansen & Coppens multipolar pseudo-atom model to derive molecular electron density and electrostatic potential distributions. The library values are obtained from several small peptide or amino acid crystal structures refined against ultra-high-resolution X-ray diffraction data. The library transfer is applied automatically in the MoPro software suite to peptide and protein structures measured at atomic resolution. The transferred multipolar parameters are kept fixed while the positional and thermal parameters are refined. This enables a proper deconvolution of thermal motion and valence-electron-density redistributions, even when the diffraction data do not extend to subatomic resolution. The use of the experimental library multipolar atom model (ELMAM) also has a major impact on crystallographic structure modelling in the case of small-molecule crystals at atomic resolution. Compared to a spherical-atom model, the library transfer results in a more accurate crystal structure, notably in terms of thermal displacement parameters and bond distances involving H atoms. Upon transfer, crystallographic statistics of fit are improved, particularly free R factors, and residual electron-density maps are cleaner. [source] The invariom model and its application: refinement of d,l -serine at different temperatures and resolutionACTA CRYSTALLOGRAPHICA SECTION A, Issue 3 2005B. Dittrich Three X-ray data sets of the same d,l -serine crystal were measured at temperatures of 298, 100 and 20,K. These data were then evaluated using invarioms and the Hansen & Coppens aspherical-atom model. Multipole populations for invarioms, which are pseudoatoms that remain approximately invariant in an intermolecular transfer, were theoretically predicted using different density functional theorem (DFT) basis sets. The invariom parameters were kept fixed and positional and thermal parameters were refined to compare the fitting against the multi-temperature data at different resolutions. The deconvolution of thermal motion and electron density with respect to data resolution was studied by application of the Hirshfeld test. Above a resolution of sin,/,,,,0.55,Å,1, or d,,,0.9,Å, this test was fulfilled. When the Hirshfeld test is fulfilled, a successful modeling of the aspherical electron density with invarioms is achieved, which was proven by Fourier methods. Molecular geometry improves, especially for H atoms, when using the invariom method compared to the independent-atom model, as a comparison with neutron data shows. Based on this example, the general applicability of the invariom concept to organic molecules is proven and the aspherical density modeling of a larger biomacromolecule is within reach. [source] Five-dimensional structure refinement of natural melilite, (Ca1.89Sr0.01Na0.08K0.02)(Mg0.92Al0.08)(Si1.98Al0.02)O7ACTA CRYSTALLOGRAPHICA SECTION B, Issue 6 2001Luca Bindi The structure of a crystal of natural melilite from San Venanzo, Umbria (Italy) of the general formula X2T1(T2)2O7, where X = Ca0.945Sr0.005Na0.04K0.01, T1 = Mg0.92Al0.08 and T2 = Si0.99Al0.01, has been solved and refined as an incommensurate structure in five-dimensional superspace. The structure is tetragonal, superspace group P21m:p4mg, cell parameters a = 7.860,(1), c = 5.024,(1),Å, modulation vectors q1 = 0.2815,(3)(a* + b*), q2 = 0.2815,(3)(,a* + b*). The data collection was performed on a KumaCCD diffractometer. The structure was refined from 7606 reflections to final R = 0.0481. A special modification of the refinement program Jana2000 was necessary to take into account overlapping of satellite reflections m×n = ±1, which could not be properly separated in the integration procedure. The final model includes modulations of the atomic positions as well as modulations of the thermal parameters. The latter are induced by strong differences in the neighbourhood of the actual modulated positions. The occupational modulation was neither significant for X nor for T1 sites and the sites were supposed to be occupied only by Ca and Mg, respectively. As a consequence of the Ca and O positional modulations six-, seven- and eightfold Ca coordination occur throughout the structure and the thermal ellipsoid changes its shape correspondingly. The positional modulation of the atoms causes variations in the interatomic distances which, however, do not affect bond-valence sums considerably, but induce flattening and rotation in T1 and T2 tetrahedra, respectively. [source] Application of normal-mode refinement to X-ray crystal structures at the lower resolution limitACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2009Fengyun Ni The structural refinement of large complexes at the lower resolution limit is often difficult and inefficient owing to the limited number of reflections and the frequently high-level structural flexibility. A new normal-mode-based X-ray crystallographic refinement method has recently been developed that enables anisotropic B -factor refinement using a drastically smaller number of thermal parameters than even isotropic refinement. Here, the method has been systematically tested on a total of eight systems in the resolution range 3.0,3.9,Å. This series of tests established the most applicable scenarios for the method, the detailed procedures for its application and the degree of structural improvement. The results demonstrated substantial model improvement at the lower resolution limit, especially in cases in which other methods such as the translation,libration,screw (TLS) model were not applicable owing to the poorly converged isotropic B -factor distribution. It is expected that this normal-mode-based method will be a useful tool for structural refinement, in particular at the lower resolution limit, in the field of X-ray crystallography. [source] Structural improvement of unliganded simian immunodeficiency virus gp120 core by normal-mode-based X-ray crystallographic refinementACTA CRYSTALLOGRAPHICA SECTION D, Issue 4 2009Xiaorui Chen The envelope protein gp120/gp41 of simian and human immunodeficiency viruses plays a critical role in viral entry into host cells. However, the extraordinarily high structural flexibility and heavy glycosylation of the protein have presented enormous difficulties in the pursuit of high-resolution structural investigation of some of its conformational states. An unliganded and fully glycosylated gp120 core structure was recently determined to 4.0,Å resolution. The rather low data-to-parameter ratio limited refinement efforts in the original structure determination. In this work, refinement of this gp120 core structure was carried out using a normal-mode-based refinement method that has been shown in previous studies to be effective in improving models of a supramolecular complex at 3.42,Å resolution and of a membrane protein at 3.2,Å resolution. By using only the first four nonzero lowest-frequency normal modes to construct the anisotropic thermal parameters, combined with manual adjustments and standard positional refinement using REFMAC5, the structural model of the gp120 core was significantly improved in many aspects, including substantial decreases in R factors, better fitting of several flexible regions in electron-density maps, the addition of five new sugar rings at four glycan chains and an excellent correlation of the B -factor distribution with known structural flexibility. These results further underscore the effectiveness of this normal-mode-based method in improving models of protein and nonprotein components in low-resolution X-ray structures. [source] Structure of DsbC from Haemophilus influenzaeACTA CRYSTALLOGRAPHICA SECTION D, Issue 9 2004Man Zhang Bacterial DsbC proteins are involved in rearranging or reducing mismatched disulfide bonds folding within the periplasm. The X-ray structure of the enzyme from Haemophilus influenzae has been solved and compared with the known structure of the Escherichia coli protein. The proteins act as V-shaped dimers with a large cleft to accommodate substrate proteins. The dimers are anchored by a small N-terminal domain, but have a flexible linker region which allows the larger C-terminal domain, with its reactive sulfhydryls, to clamp down on substrates. The overall folds are very similar, but the comparison shows a wider range of hinge motions than previously thought. The crystal packing of the H. influenzae protein allows the movement of the N-terminal domain with respect to the C-terminal domain through motions in the flexible hinge, generating high thermal parameters and unusually high anisotropy in the crystallographic data. [source] Near-atomic resolution crystal structure of an A-DNA decamer d(CCCGATCGGG): cobalt hexammine interaction with A-DNAACTA CRYSTALLOGRAPHICA SECTION D, Issue 1 2003Boopathy Ramakrishnan The structure of the DNA decamer d(CCCGATCGGG) has been determined at 1.25,Å resolution. The decamer crystallized in the tetragonal space group P43212, with unit-cell parameters a = b = 44.3, c = 24.8,Å and one strand in the asymmetric unit. The structure was solved by the molecular-replacement method and refined to Rwork and Rfree values of 16.3 and 18.5%, respectively, for 5969 reflections. The decamer forms the A-form DNA duplex, with the abutting crystal packing typical of A-DNA. The crystal packing interactions seem to distort the local conformation: A5 adopts the trans/trans conformation for the torsion angles , and , instead of the usual gauche,/gauche+ conformations, yielding G*(G·C) base triplets. The highly hydrated [Co(NH3)6]3+ ion adopts a novel binding mode to the DNA duplex, binding directly to phosphate groups and connecting to N7 and O6 atoms of guanines by water bridges. Analysis of thermal parameters (B factors) shows that the nucleotides involved in abutting crystal packing are thermally more stable than other nucleotides in the duplex. [source] | ||||||||||||||||||||||||||||