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101.
Raphaël Côte 《纯数学与应用数学通讯》2015,68(11):1946-2004
We consider finite energy corotational wave maps with target manifold teratumonline.com/cms/attachment/752e8342-01a6-4bdc-a579-1aca78867e8d/cpa21545-math-0001.png">. We prove that for a sequence of times, they decompose as a sum of decoupled harmonic maps in the light cone, and a smooth wave map (in the blowup case) or a linear scattering term (in the global case), up to an error which tends to 0 in the energy space. © 2015 Wiley Periodicals, Inc. 相似文献
102.
M.A. Loroño Gonzalez M. Loëte M.-T. Bourgeois M. Herman Yu.N. Ponomarev A.M. Solodov 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(15):2265-2278
Ethylene (ethene, H2C=CH2) is a naturally occurring compound in ambient air that affects atmospheric chemistry and global climate. The C2H4 spectrum is available in databases only for the 1000 and 3000 cm−1 ranges.In this work, the ethylene absorption spectrum was measured in the 6030-6250 cm−1 range with the use of a high resolution Bruker IFS 125HR Fourier-spectrometer and a two-channel opto-acoustic spectrometer with a diode laser. As a secondary standard of wavelengths, the methane absorption spectrum was used in both cases.A preliminary analysis was realized thanks to the tensorial formalism developed by the Dijon group that is implemented in the XTDS software package [39]. We considered the two combination bands ν5+ν9 and ν5+ν11 as an interacting dyad. Parameters for the ν9/ν11 dyad were fitted simultaneously from a re-analysis of previously recorded supersonic expansion jet FTIR data, while parameters for the v5=1 Raman level were taken from literature. More than 600 lines could be assigned in the 6030-6250 cm−1 region (and also 682 in the 2950-3150 cm−1 region) and effective Hamiltonian parameters were fitted, including Coriolis interaction parameters. The dyad features are globally quite well reproduced, even if there are still problems at high J values. 相似文献
103.
Jacquemin D Femenias A Chermette H Ciofini I Adamo C André JM Perpète EA 《The journal of physical chemistry. A》2006,110(17):5952-5959
We have optimized the ground-state geometry of nine series of increasingly long oligomers, using six hybrid density functionals (O3LYP, B3LYP, B97-1, B98, PBE0, and BHHLYP) combined with three different atomic basis sets. In each case, the obtained bond length alternation (BLA) is compared to the corresponding MP2 values. Three phenomenological categories have been set up. In the first, the BLA exponentially decreases, in which case all the tested functionals give results in very good agreement with MP2. In the second category fall the symmetric oligomers that, due to the Peierls theorem, show large BLA. For these chains, BHHLYP tends to give too large and quickly converging BLA wrt chain length, while O3LYP often leads to the opposite misjudgments, and the remaining hybrids provide valuable results. In the third category, one finds asymmetric compounds presenting significantly unequal bond lengths, for which the divergence between DFT and wave function approaches can be dramatic. Indeed, all hybrids yield too small BLA values, especially for long chain lengths. We also study the effect of chain conformation on the BLA. 相似文献
104.
105.
106.
Marcel?W.?C.?P.?Franse Klaas?te?NijenhuisEmail author Stephen?J.?Picken 《Rheologica Acta》2003,42(5):443-453
The structural and dynamical properties of a physical network in a discotic side-chain polymer solution have been studied. For that purpose, use has been made of rheological measurements and a statistical network model for the crosslinking of polymer. The goal of the investigation was to gain more insight into processes playing important roles in the subtle interactions between discotic side-chain polymers. A relatively simple mechanical model is presented to describe the mechanical behaviour of the solutions. Moreover, results are shown for the specific dynamic as well as structural properties of the physical networks in these solutions. 相似文献
107.
108.
M P te Booy A Faber E de Jonge E P Wolterink W Riethorst T Beugeling A Bantjes J Over B W K?nig 《Journal of chromatography. A》1990,503(1):103-114
The optimization of a new process for the extraction of human coagulation factor VIII (FVIII) from plasma with the tailor-made affinity matrix dimethylamino-propylcarbamylpentyl-Sepharose CL-4B (C3-C5 matrix) is described. First, plasma is applied to DEAE-Sephadex A-50 anion exchanger in order to separate a number of proteins, including coagulation factors II, IX and X (prothrombin complex), from FVIII. Subsequently, the unbound fraction of the ion exchanger, containing FVIII, is contacted with the C3-C5 affinity matrix. Optimization of the FVIII affinity chromatographic procedure is accomplished in terms of the ligand density of the matrix, adsorption mode (batch-wise versus column-wise adsorption and matrix to plasma ratio), and conditions of pH and conductivity to be applied on washing and desorption. In scale-up experiments, by processing 20 l of plasma, the recovery (340 U VIII:C/kg plasma) and the specific activity (s.a.) (1.2 U VIII:C/mg protein) are better than those obtained by cryoprecipitation (recovery 300 U VIII:C/kg plasma, s.a. 0.3 U VIII:C/mg protein). The newly developed process using the specially designed C3-C5 affinity matrix has potential application in the process-scale purification of FVIII. 相似文献
109.
K. te Nijenhuis 《Colloid and polymer science》1981,259(10):1017-1026
Summary This second paper on the ageing of aqueous gelatin gels (1–5%) deals with the mechanism of the renaturation process. The maximum gelation temperature, i. e. the gel temperature, increases with increasing concentration. For the heat of cross-linking a value of tent/xv84550604164284/xxlarge916.gif" alt="Delta" align="BASELINE" BORDER="0">H° = - 442 kJ/mol was found, corresponding with mono-helices of 24 windings and a length of 230 Å. The influence of the thermal history is considerable, and the heat of activation of the rate determining step is very small. Hence, the temperature dependence of the degree of ageing is not caused by temperature dependence of the reaction rate constant, but by the increase in stability of small structures which accompanies a decrease in temperature.
te>Zusammenfassung Diese zweite Veröffentlichung betreffs der Alterung von 1–5% Lösungen von Gelatin in Wasser behandelt den Mechanismus des Renaturationprozesses. Die maximale Gelierungstemperatur, d. h. die Geltemperatur, nimmt zu mit zunehmender Konzentration. Für die Verknüpfungswärme wurde gefunden tent/xv84550604164284/xxlarge916.gif" alt="Delta" align="BASELINE" BORDER="0">H° = -442 kJ/mol. Dieser Wert korrespondiert mit Monohelices von 24 Windungen und einer Länge von 230 Å. Die Abhängigkeit von der thermischen Geschichte ist bedeutend und die Aktivierungsenergie des geschwindigkeitsbestimmenden Reaktionsschrittes ist sehr klein. Demnach wird die Temperaturabhängigkeit des Alterungsgrades nicht verursacht durch die Temperaturabhängigkeit der Reaktionsgeschwindigkeitskonstante, sondern durch die Zunahme der Stabilität kleiner Strukturen mit abnehmender Temperatur. te> 相似文献
110.
Belletête M Durocher G Hamel S Côte M Wakim S Leclerc M 《The Journal of chemical physics》2005,122(10):104303
The molecular structure of three ladder oligo(p-aniline)s, 5,11-diethyl-6,12-dimethylindolo[3,2-b]carbazole (DIMER 2P), 14-ethyl-5,8-dihydro-diindolo[3,2-b:2',3'-h]carbazole (TRIMER 2P), and 5,8,14-triethyl-diindolo[3,2-b:2',3'-h]carbazole (TRIMER 3P) were investigated by first principles calculations at the Hartree-Fock (HF6-31G*) and density functional theory (DFTB3LYP6-31G*) levels. It is found that the agreement between theoretical and x-ray geometrical parameters is good and rather similar for both theoretical methods. The nature and the energy of the first two singlet-singlet electronic transitions have been obtained by Zerner intermediate neglect of differential overlap/spectroscopy semiempirical calculations performed on the HF6-31G* and DFTB3LYP6-31G* optimized geometries, as well as time-dependent density functional theory (TDDFT) calculations performed on the DFTB3LYP6-31G* optimized structures. For all the compounds and for all the theoretical approaches, it is observed that the S(1)<--S(0) electronic transition (pipi*) is weakly allowed and polarized along the short axis (y) of the molecule. On the other hand, the S(2)<--S(0) electronic transition of each oligomer possesses a much larger oscillator strength and is polarized along the long (x) molecular axis. It is found that TDDFT calculations provide the best overall agreement between the energies and the corresponding optical transitions obtained from the absorption bands (0-0 peaks) measured in dichloromethane as well as providing a good evaluation of the bathochromic shifts caused by the increase in the conjugation length or by the presence of extra alkyl chains on the nitrogen atoms in TRIMER 3P compared to TRIMER 2P. 相似文献