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941.
基于已有的动力学数据对单颗粒黄铁矿迁移转化进行了全过程模拟,分析讨论了各种因素对黄铁矿氧化过程和S释放率的影响,结果表明:随着颗粒尺寸的减小和炉膛温度的升高,黄铁矿颗粒的分解氧化过程加快,颗粒在炉内停留很短时间内温度即升高到共融点以上,使颗粒呈混熔态,进而导致灰沉积、结渣.颗粒氧化过程中S的释放主要受扩散控制,其释放速率与颗粒粒径成反比,与氧气浓度和炉膛温度成正比.  相似文献   
942.
In the applications of primary spectrum pyrometry, based on the dynamic range and the minimum sensibility of the sensor, the application issues, such as the measurement range and the measurement partition, were investigated through theoretical analyses. For a developed primary spectrum pyrometer, the theoretical predictions of measurement range and the distributions of measurement partition were presented through numerical simulations. And the measurement experiments of high-temperature blackbody and standard temperature lamp were processed to further verify the above theoretical analyses and numerical results. Therefore the research in the paper provides the helpful supports for the applications of primary spectrum pyrometer and other radiation pyrometers.  相似文献   
943.
A study of the dynamical fluctuation properties at various c.m. Energies in e+e- collisions is performed using the Monte Carlo method. The results suggest that, after the normalized factorial moments of 3-dimensional phase space are analyzed using an isotropical phase space partition, the NFM describing non-linear dynamical properties show a power-law scaling, I.e., the dynamical fluctuations in higher dimensional phase space are isotropic. For c.m. Energies √s≤80 GeV,the scaling exponents φq increase rapidly with the c.m. Energy and for c.m. Energies √s>80 GeV,the φq gradually saturate.  相似文献   
944.
For Ramanujan’s modular identities connected with his well-known partition congruences for the moduli 5 or 7, we had given, in an earlier paper, natural and uniform proofs through the medium of modular forms. Analogous (modular) identities corresponding to the (more difficult) case of the modulus 11 are provided here, with the consequent partition congruences; the relationship with relevant results of N J Fine is also sketched.  相似文献   
945.
A synthetic peptide corresponding to the signal sequence ofE. coli alkaline phosphatase has been synthesized by the solid phase method employing the transesterification method of cleavage from the resin. The protected peptide obtained after cleavage was purified to homogeneity by column chromatography on silica gel, followed by partition chromatography on SephadexLH-20 using organic solvents like chloroform and methanol as eluants.  相似文献   
946.
The translation inconsistency in the theory of nucleation is discussed in historical perspective. A theory is then developed, beginning with the classical phase integral, which not only allows all approximations to be well defined, but also leads to the most natural droplike model for the cluster. The theory makes it possible to apply, in a consistent manner, the thermodynamics of curved surfaces or, alternatively, moleculardynamic numerical computation schemes to the evaluation of the partition function of the cluster. If the cluster is treated as a macroscopic drop (having the free energy of a macroscopic drop), the result for the distribution of clusters differs in only a minor way from that prescribed by the conventional theory of nucleation. It is concluded that for liquid nuclei the conventional theory is consistent, but that a replacement factor may be necessary for solid nuclei. In general, however, the major problems confronting the theory involve the precise evaluation of the work of cluster formation.  相似文献   
947.
We study the limiting behavior of uniform measures on finite-dimensional simplices as the dimension tends to infinity and a discrete analog of this problem, the limiting behavior of uniform measures on compositions. It is shown that the coordinate distribution of a typical point in a simplex, as well as the distribution of summands in a typical composition with given number of summands, is exponential. We apply these assertions to obtain a more transparent proof of our result on the limit shape of partitions with given number of summands, refine the estimate on the number of summands in partitions related to a theorem by Erds and Lehner about the asymptotic absence of repeated summands, and outline the proof of the sharpness of this estimate.  相似文献   
948.
Based on bonding parameters such as Yang's Electronegative Force Gauge Y(i), electronic number of valence layer Z(i), number of combined hydrogen atoms h(i), number of bonding electron b(i), and quantum number such as the highest main quantum number of valence layer n(i), a novel atomic valence delta(i) (Y) is defined and a novel topological index (1)chi(Y) is derived from the atomic valence. The atomic valence is defined as delta(i) (Y) = (Z(i) - h(i))b(i)/n(i) (2)Y(i), while the topological index is expressed as (1)chi(Y) summation operator (i,j=1) (m) (delta(i) (Y)delta(j) (Y))(-1/2). Subsequently, the index (1)chi(Y) is utilized to study the structure-property relationships of complex organic compounds. The results of correlativity showed that the index is highly and extensively correlated with such properties as solubility of phenyl chlorides, gas chromatographic retention index of alkoxyl silanes, and toxicity of heterocyclic nitrogen-containing compounds. Moreover, predicted values are quite consistent with experimental ones when the index is employed to predict the partition coefficient (log P) of fatty alcohols, phenyl chlorides, and barbitals. Compared to the topological indices reported in the literature, the universality and reliability of (1)chi(Y) to the properties of complex organic compounds have been distinctively improved, and its calculating process is simple and convenient.  相似文献   
949.
An analytical expression for the phase shift contribution to the internal partition function for the Morse potential is derived by using an approximate Jost function. This function is shown to be a convergent sum. The numerical results obtained for H2 and HCl show the partition function to be a monotonically increasing function of temperature. This observation agrees with the results of Rogers and co-workers. Work supported in part by the Department of Atomic Energy, Government of India.  相似文献   
950.
赵凤珍 《数学研究》1996,29(1):84-86
本文用简便的方法,得到了一些Rogers-Ramanujan恒等式的广义形式.  相似文献   
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