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31.
We study the kinetic behavior of a two-species aggregation-migration model in which an irreversible aggregation
occurs between any two clusters of the same species and a reversible migration occurs simultaneously between two different species. For a simple model with constant aggregation rates and
with the migration rates
KA(i;j)=K'A(i;j) ∝ijv1 and
KB(i;j)=K'B(i;j) ∝ijv2, we find that the evolution behavior of the system depends crucially on the
values of the indexes v1 and v2. The aggregate size
distribution of either species obeys a conventional scaling law for most cases. Moreover, we also generalize the two-species system to the multi-species case and analyze its kinetic behavior
under the symmetrical conditions. 相似文献
32.
We have studied the kinetic behaviours of irreversible aggregation-annihilation models with cluster removals. In the models, an irreversible aggregation reaction occurs between any two clusters of the same species and an irreversible annihilation reaction occurs simultaneously between two different species; meanwhile, the clusters of large size are gradually removed from the system. In a mean-field limit, we obtain the general solutions of the cluster-mass distributions for the cases with an arbitrary removal probability. We found that the cluster-mass distribution of either species satisfies a generalized or modified scaling form. The results also indicate that the evolution behaviours of the systems depend strongly on the details of the reaction events. 相似文献
33.
34.
Zhen-Quan Li 《Journal of Dispersion Science and Technology》2013,34(12):1624-1632
The dilational viscoelastic properties of hydrophobically modified partly hydrolyzed polyacrylamide and anionic surfactants (4,5-diheptyl-2-propylbenzene sulfonate and gemini surfactant C12COONa-p-C9SO3Na) in the absence or presence of electrolyte have been investigated at the decane–water interface by means of longitudinal method and the interfacial tension relaxation method. Experimental results show that at low surfactant concentration, the increase of the dilational modulus by the addition of surfactant molecules at low frequency might be explained by the mix-adsorption of the polymer chains and surfactant molecules. At the same time, polymer chain could sharply decrease the dilational modulus of surfactant film mainly due to the weakening of the strong interactions among long alkyl chains in surfactant molecules. At high surfactant concentration, the addition of surfactant molecules can decrease the dilational modulus of polymer solution due to the fast process involving in the exchange of surfactant molecules between the interface and the mixed complex formed by surfactant molecules and hydrophobic micro-domains. The added electrolyte, which results in screening of electrostatic interactions between the ionized groups, generally increases the frequency dependence of the interfacial dilational modulus. The data obtained on the relaxation processes via interfacial tension relaxation measurements can explain the results from oscillating barriers measurements very well. 相似文献
35.
本文应用紫外-可见吸收光谱研究了甲苯胺蓝在十二烷基苯磺酸钠中的聚合状态,分析了有表面活性剂存在下氯化钠对甲苯胺蓝解聚作用的影响。结果表明,无机盐促使十二烷基苯磺酸钠提前形成胶束(预胶束),造成甲苯胺蓝二聚体的解聚。 相似文献
36.
A competition model of three species in exchange-driven aggregation growth is proposed. In the model, three distinct aggregates grow by exchange of monomers and in parallel, birth of species A is catalyzed by species B and death of species A is catalyzed by species C. The rates for both catalysis processes are proportional to kj^v and ky respectively, where ν(ω) is a parameter reflecting the dependence of the catalysis reaction rate of birth (death) on the catalyst aggregate's size. The kinetic evolution behaviors of the three species are investigated by the rate equation approach based on the mean-field theory: The form of the aggregate size distribution of A-species αk(t) is found to be dependent crucially on the two catalysis rate kernel parameters. The results show that (i) in case of ν ≤O, the form of ak (t) mainly depends on the competition between self-exchange of species A and species-C-catalyzed death of species A; (ii) in case of ν 〉 0, the form of αk(t) mainly depends on the competition between species-B-catalyzed birth of species A and species-C-catalyzed death of species A. 相似文献
37.
We propose an adsorption-desorption model for a deposit growth system, in which the adsorption and desorption of particles coexist. By means of the generalized rate equation we investigate the cluster (island) size distribution in the dynamic equilibrium state. The results show that the evolution behaviour of the system depends crucially on the details of the rate kernels. The cluster size distribution can take the scale-free power-law form in some cases, while it grows exponentially with size in other cases. 相似文献
38.
We propose a catalytically activated duplication model to mimic the
coagulation and duplication of the DNA polymer system under the
catalysis of the primer RNA. In the model, two aggregates of the
same species can coagulate themselves and a DNA aggregate of any
size can yield a new monomer or double itself with the help of RNA
aggregates. By employing the mean-field rate equation approach we
analytically investigate the evolution behaviour of the system. For
the system with catalysis-driven monomer duplications, the aggregate
size distribution of DNA polymers ak(t) always follows a power
law in size in the long-time limit, and it decreases with time or
approaches a time-independent steady-state form in the case of the
duplication rate independent of the size of the mother aggregates,
while it increases with time increasing in the case of the
duplication rate proportional to the size of the mother aggregates.
For the system with complete catalysis-driven duplications, the
aggregate size distribution ak(t) approaches a generalized or
modified scaling form. 相似文献
39.
SUN Yun-Fei CHEN Dan LIN Zhen-Quan KE Jian-Hong 《理论物理通讯》2009,51(6):1042-1054
We propose a solvable aggregation model to mimic the evolution of population A, asset B, and the quantifiable resource C in a society. In this system, the population and asset aggregates themselves grow through selfexchanges with the rate kernels Kl(k,j) = K1kj and K2(h,j) = K2kj, respectively. The actions of the population and asset aggregations on the aggregation evolution of resource aggregates are described by the population-catalyzed monomer death of resource aggregates and asset-catalyzed monomer birth of resource aggregates with the rate kerne/s J1(k,j)=J1k and J2(k,j) = J2k, respectively. Meanwhile, the asset and resource aggregates conjunctly catalyze the monomer birth of population aggregates with the rate kernel I1 (k,i,j) = I1ki^μjη, and population and resource aggregates conjunctly catalyze the monomer birth of asset aggregates with the rate kernel /2(k, i, j) = I2ki^νj^η. The kinetic behaviors of species A, B, and C are investigated by means of the mean-field rate equation approach. The effects of the population-catalyzed death and asset-catalyzed birth on the evolution of resource aggregates based on the self-exchanges of population and asset appear in effective forms. The coefficients of the effective population-catalyzed death and the asset-catalyzed birth are expressed as J1e = J1/K1 and J2e= J2/K2, respectively. The aggregate size distribution of C species is found to be crucially dominated by the competition between the effective death and the effective birth. It satisfies the conventional scaling form, generalized scaling form, and modified scaling form in the cases of J1e〈J2e, J1e=J2e, and J1e〉J2e, respectively. Meanwhile, we also find the aggregate size distributions of populations and assets both fall into two distinct categories for different parameters μ,ν, and η: (i) When μ=ν=η=0 and μ=ν=η=1, the population and asset aggregates obey the generalized scaling forms; and (ii) When μ=ν=1,η=0, and μ=ν=η=1, the population and asset aggregates experience gelation transitions at finite times and the scaling forms break down. 相似文献
40.
We propose an aggregation evolution model of two-species (A- and B-species) aggregates to study the prevalent aggregation phenomena in social and economic systems. In this model, A- and B-species aggregates perform self-exchange-driven growths with the exchange rate kernels K(k, l) = Kkl and L(k, l) = Lkl, respectively, and the two species aggregates perform self-birth processes with the rate kernels J1(k) = J1 k and J2( k ) = J2k, and meanwhile the interaction between the aggregates of different species A and B causes a lose-lose scheme with the rate kernel H(k,l) = Hkl. Based on the mean-field theory, we investigated the evolution behaviors of the two species aggregates to study the competitions among above three aggregate evolution schemes on the distinct initial monomer concentrations A0 and B0 of the two species. The results show that the evolution behaviors of A- and B-species are crucially dominated by the competition between the two self-birth processes, and the initial monomer concentrations Ao and Bo play important roles, while the lose-lose scheme play important roles in some special cases. 相似文献