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81.
荧光光谱法研究钙试剂羧酸钠与牛血清白蛋白结合反应特征 总被引:17,自引:0,他引:17
不同温度下,研究了钙试剂羧酸钠与牛血清白蛋白作用的荧光猝灭光谱、同步荧光光谱、三维荧光光谱和紫外可见吸收光谱特征;分别用SternVolmer方程和LineweaverBurk双倒数方程等处理实验数据,得到了26℃时反应的结合常数为7.664×104mol/L,结合位点数为1.522,结合反应的标准焓变、标准熵变和标准吉布斯自由能变分别为-58.36kJ/mol,-101.7J/K和-27.958kJ/mol;分析所得光谱,证实了在实验浓度和温度范围内,CCS与BSA反应可形成具有一定结构的复合物,获得了CCS对BSA构型的影响等重要信息。 相似文献
82.
To study the coherence of thermodynamic data of the AgNO3-LiNO3 -RbNO3 ternary system, phase diagram of the binary system AgNO3 -LiNO3 has been obtained between 303 and 550 K by direct and differential thermal analysis technique. This system is characterized
by an eutectic point (25% mol. LiNO3 , 445±1 K) and a plateau due to the solid-solid transition in AgNO3 at 434±1 K. In the solid state the solubility of each component in the other seems to be nil or negligible (no more than
a few percents). Using other thermodynamic data, the excess properties of the binary liquid (AgNO3 - LiNO3 ) were calculated at 623 K.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
83.
Guo‐Xu Zhang Ying Xie Hai‐Tao Yu Hong‐Gang Fu 《Journal of computational chemistry》2009,30(12):1785-1798
The structural and electronic properties of five terminations of cubic lead titanate (PbTiO3) (110) polar surface were investigated by first‐principles total‐energy calculations using a periodic slab model. On the PbTiO termination, an anomalous filling of conduction band was observed, whereas on the O2 termination, two surface oxygen atoms formed a peroxo group, demonstrating that the electronic structures of the two stoichiometric terminations undergo significant changes with respect to bulk materials. However, for the three nonstoichiometric TiO‐, Pb‐, and O‐terminated surfaces, their electronic structures are very similar to bulk. Charge redistribution results for the five terminations confirmed that electronic structure and surface composition changes are responsible for their polarity compensation. However, which mechanism actually dominates the stabilization process depends upon energetic considerations. A thermodynamic stability diagram suggested that the two stoichiometric terminations are unstable; however, the three nonstoichiometric terminations can be stabilized in some given regions. Furthermore, this study indicates that the very different stabilities and surface states filling behaviors of the PbTiO3 (110) polar surface with respect to SrTiO3 and BaTiO3 ones seem to originate from the partially covalent characteristics of Pb O pairs. © 2008 Wiley Periodicals, Inc. J Comput Chem 2009 相似文献
84.
We describe a method for representing the nonlinear system of gas dynamics equations in quasilinear form with symmetric coefficient matrices and, moreover, with a positive definite matrix at the time derivative. 相似文献
85.
Sieck L. Wayne Heron John T. Green David S. 《Plasma Chemistry and Plasma Processing》2000,20(2):235-258
Reliable kinetic and thermodynamic data are required to model the evolution of electric discharge or electron-beam decomposition chemistry of gases in humid air streams. In this first segment of a continuing series, we provide a core database describing the initially dominant ion-neutral molecule reactions in humid air plasmas. Recommended reaction rate data and extrapolation tools are presented in a manner to facilitate prediction of reactivities and reaction channels as a function of temperature, pressure, and applied electric field. 相似文献
86.
87.
G. G. Gospodinov G. Baikusheva-Dimitrova 《Journal of Thermal Analysis and Calorimetry》2000,61(3):885-888
By using a DSK of the French firm Seteram, the standard enthalpies of formation of 5 tellurites and 5 tetratellurites of the
rare earths Gd, Tb, Dy, Tm and Yb were determined for the first time.
Three parallel determinations for each sample were compared. The results are very similar, which is an indication of the great
reliability of the method used and the correctness of the data obtained.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
88.
Mitchell J. Feigenbaum 《Journal of statistical physics》1987,46(5-6):925-932
The grand canonical version of the spectrum of singularities formalism is presented, relying naturally upon certain Markov transition graphs. The structure of a graph is simply determined by the close return times of the dynamical system described. Thus, an intimate connection exists between the shape of the singularity curve and a small but interesting set of dynamical properties. 相似文献
89.
We study the fate of the Onsager-Casimir reciprocity relations for a continuous system when some of its variables are eliminated adiabatically. Just as for discrete systems, deviations appear in correction terms to the reduced evolution equation that are of higher order in the time scale ratio. The deviations are not removed by including correction terms to the coarse-grained thermodynamic potential. However, via a reformulation of the theory, in which the central role of the thermodynamic potential is taken over by an associated Lagrangian-type expression, we arrive at a modified form of the Onsager-Casimir relations that survives the adiabatic elimination procedure. There is a simple relation between the time evolution of the redefined thermodynamic forces and that of the basic thermodynamic variables; this relation also survives the adiabatic elimination. The formalism is illustrated by explicit calculations for the Klein-Kramers equation, which describes the phase space distribution of Brownian particles, and for the corrected Smoluchowski equation derived from it by adiabatic elimination of the velocity variable. The symmetry relation for the latter leads to a simple proof that the reality of the eigenvalues of the simple Smoluchowski equation is not destroyed by the addition of higher order corrections, at least not within the framework of a formal perturbation expansion in the time scale ratio. 相似文献
90.
Gu-Qiang Li 《Theoretical and Mathematical Physics》2008,157(1):1496-1502
We use the brick-wall method to investigate the thermodynamic quantities around a charged dilaton black hole. We show that
all the thermodynamic quantities contain two terms: the first term has exactly the same form as in a flat space-time, but
the second term depends explicitly on the spin of the fields and therefore cannot be neglected.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 157, No. 1, pp. 154–160, October, 2008. 相似文献