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101.
本讨论了一类广义的Lanchester模型在一些限制条件下的近似解,并给出了若干结论。 相似文献
102.
曼合布拜·热合木 《新疆大学学报(理工版)》2003,(1)
讨论了一类具有扩散率和 III类功能性反应的非自治捕食系统 ,证明了在适当条件下 ,系统是持久的 ,进一步如果系统是周期系统 ,则在一定条件下存在惟一全局稳定的周期解 . 相似文献
103.
《Electroanalysis》2003,15(17):1377-1388
It has been demonstrated that potentiometric and polarographic data coming from either acid? base or ligand titrations can be evaluated by the same set of equations and mathematical procedures involving mass‐balance equations written for any metal? ligand model, including polynuclear species. It is shown that the concept of the complex formation curves, used previously in modeling and refinement of stability constants in acid‐base titration, is of general nature and can be successfully used in polarographic and potentiometric experiments conducted as a function of pH or an excess of a ligand. It appears that the linear relationship ΔE vs. log [M], typical for potentiometric studies with ISE, holds also in the case of the study of kinetically mixed metal‐ligand system studied by polarography when the corrected shift in the polarographic signal is used. The relationship ΔE vs. log [M] applies equally to the acid‐base and ligand titration for both experimental techniques employed (potentiometry and polarography). The significance of the corrected shift is discussed and its meaning in the study of kinetically fast or slow metal? ligand systems is elaborated. Advantages of the acid‐base titration over the ligand titration are discussed. The generalized mathematical data treatment was successfully employed in the study of the CdII? (N‐(2‐hydroxyethyl)iminodiacetic acid) system. Results obtained from both analytical techniques (potentiometry with the use of an ion selective electrode, and two polarographic techniques) and analytical procedures (acid? base and ligand titrations) compare well with each other and with the literature data (the formation and stability constants of ML and ML2). In addition, a new complex M(HL) was identified and its stability constant is reported. 相似文献
104.
Donal O'Regan 《Journal of Mathematical Analysis and Applications》2006,324(2):1370-1380
In this paper we show that the solution set of certain Volterra inclusions defined between Fréchet spaces is a continuum. The proof relies on results in Banach spaces and on viewing a Fréchet space as a projective limit of a sequence of Banach spaces. 相似文献
105.
A.S Haja Hameed A Nixon Azariah P Ramasamy 《Journal of Physics and Chemistry of Solids》2003,64(1):147-153
The metastable zone width for the solution of organic nonlinear material: indole-3-aldehyde (IA) has been determined for the various solvents of acetone, methanol and ethyl acetate and the corresponding IA crystals have been grown by temperature lowering technique. The surface analysis on different planes of the grown crystals has been carried out. The range of transmission and powder second harmonic generation efficiency of IA have been reported. 相似文献
106.
TorstenLinB 《计算数学(英文版)》2003,21(4):401-410
We consider a singularly perturbed semilinear convection-diffusion problem with a boundary layer of attractive turning-point type. It is shown that its solution can be decomposed into a regular solution component and a layer component. This decomposi-tion is used to analyse the convergence of an upwinded finite difference scheme on Shishkin meshes. 相似文献
107.
108.
Carrier diffusion and recombination kinetics in all-inorganic CsPbI3 perovskite microcrystals directly synthesized in solution phase are reported. 相似文献
109.
G. Saravanan G. Jyothi Y. Suresh A. Annerao M. Ramakrishna M. Yogeshwar Reddy B. Ravibabu 《Chromatographia》2008,67(1-2):173-177
Levetiracetam is used in combination with other medications to treat certain types of seizures in people with epilepsy. Levetiracetam
is in a class of medications called anticonvulsants and it works by decreasing abnormal excitement in the brain. A chromatographic
separation was achieved on a YMC pack ODS AQ, 250 mm × 4.6 mm, 5 μm column using diluted phosphoric acid and acetonitrile
in the ratio 85:15 v/v. Forced degradation studies were performed on the levetiracetam drug substance. The drug substance was degraded to Imp-B
during acid and base hydrolysis. When the stress samples were assayed, the mass balance was matching. The sample solution
and mobile phase was found to be stable up to 48 h at 25 °C. The developed method was validated with respect to linearity,
accuracy, precision and robustness. 相似文献
110.
Effect of solution chemistry on the fouling potential of dissolved organic matter in membrane bioreactor systems 总被引:1,自引:0,他引:1
Dissolved organic matter (DOM) as a potent foulant in membrane bioreactor (MBR) systems has attracted great attention in recent years. This paper attempts to elucidate the effect of solution chemistry (i.e. solution pH, ionic strength, and calcium concentration) on the fouling potential of DOM with different characteristics. Results of microfiltration experiments showed that the fouling potential of DOM having higher hydrophobic content increased more markedly at low pH due to the reduced ionization of carboxylic and phenolic functional groups of aquatic humic substances. In contrast, the fouling potential of hydrophilic DOM components and the molecular size of DOM appeared to be less affected by solution pH. The more compact molecular configuration of DOM at high ionic strength contributed to form a denser fouling layer, and limited the amount of foulants retained by the membranes on the other hand. DOM fouling potential greatly increased with increasing calcium concentration. The magnitude of the increase, however, was independent of the hydrophobicity of DOM, suggesting strong interactions exist between calcium ions and hydrophilic DOM components. Moreover, it was observed that the main mechanism governing the effect of calcium ions on the molecular size of DOM transited from charge shielding to complex formation as calcium concentration increased. 相似文献