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71.
Nonlinear Dynamics - In the present article, a combination of numerical and experimental studies is undertaken to comprehend the influence of noise on the responses of continuous-time dynamical... 相似文献
72.
Thin flakes of tin disulphide single crystals grown using direct vapour transport have been subjected to characterization to unfold their growth mechanism. Two types of spirals. viz. those having opposite orientation present on the same face and those present on the opposite finished faces are significantly discussed. 相似文献
73.
Single crystals of MoSe2 of fairly large size have been grown by the sublimation method. A careful study of microstructures on the as-grown faces has revealed a variety of surface patterns. All these features have been critically studied and the implications have been discussed. 相似文献
74.
Response surface methodology (RSM) was employed for optimization of medium components and cultural parameters in cost effective
cane molasses based medium for attaining high yield of succinic acid. The important factors obtained by “one-variable-at-a-time-approach”
(cane molasses, corn steep liquor, sodium carbonate, and inoculum density) were further optimized by RSM. The optimum values
of the parameters obtained through RSM (cane molasses 12.5%, corn steep liquor 7.5%, and sodium carbonate 25 mM) led to almost
double yield of succinic acid (15.2 g/l in 36 h) as against “one-variable-at-a-time-approach” (7.1 g/l in 36 h) in 500-ml
anaerobic bottles containing 300-ml cane molasses based medium. Subsequently, in 10-l bioreactor succinic acid production
from Escherichia coli was further improved to 26.2 g/l in 30 h under conditions optimized through RSM. This fermentation-derived succinic acid
will definitely help in replacing existing environmentally hazardous and cost-intensive chemical methods for the production
of succinic acid. 相似文献
75.
Ravi P. Agarwal 《Nonlinear Analysis: Theory, Methods & Applications》2010,72(6):2859-124
We consider a differential equation of fractional order with uncertainty and present the concept of solution. It extends, for example, the cases of first order ordinary differential equations and of differential equations with uncertainty. Some examples are presented. 相似文献
76.
Ravi P. Agarwal Donal O’Regan Svatoslav Staněk 《Central European Journal of Mathematics》2009,7(4):694-716
The paper is concerned with existence results for positive solutions and maximal positive solutions of singular mixed boundary
value problems. Nonlinearities h(t;x;y) in differential equations admit a time singularity at t=0 and/or at t=T and a strong singularity at x=0. 相似文献
77.
K. Pradeesh Monika Agarwal K. Koteswara Rao G. Vijaya Prakash 《Solid State Sciences》2010,12(1):95-98
Quasi-one-dimensional lead (II) iodide compound, C14H18N2Pb2I6, with unique crystal structure was synthesized and solved for the crystal structure. These novel inorganic-organic hybrids have high thermal stability of upto 300 °C and show excitonic and charge-transfer features in their optical properties. An attempt has been made to understand the structural and optical mechanisms between inorganic one-dimensional polymeric PbI nano ribbons and the guest organic moiety for future applications in nanoscaled electronic devices. 相似文献
78.
79.
Crystallization kinetics and thermodynamic properties of nucleated isotactic polypropylene (PP) are analyzed using Hoffman—Lauritzen crystallization theory to determine the mechanistic effects of the nucleators. Calorimetric data provides quantitative comparisons between nucleating efficiences of the (Millad) and (NJSTAR) nucleator in Metallocene (M) and Ziegler—Natta (ZN) PP. The two types of PP without nucleators showed similar crystallization behavior though the T°m for ZN-iPP was about 10°C higher than M-iPP. Both nucleators show significant improvement in crystallization rate in both types of PP. In addition, Millad outperforms NJSTAR. The magnitude of the kinetic response is,however, different and both the nucleators appear to function better in ZN than in Metallocene PP. nucleated PP shows predominantly the form. The amount of the form is thermal history dependent and changes with supercooling (T=T°m–Tc). Similar equilibrium melting temperature (T°m) in the nucleated and control PPs indicates the lack of any thermodynamic effect of the nucleator. All nucleated PPs show a much lower secondary nucleation rate constant, Kg.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
80.
Ravi P. Agarwal X.H. Tang Z.C. Wang 《Journal of Mathematical Analysis and Applications》1999,240(2):1
In this paper, we shall consider a class of neutral differential equations of the form
where τ (0, ∞), σ [0, ∞), Q(t) C([t0, ∞), R + ), r(t) C([t0, ∞), (0, ∞)) with r(t) nondecreasing on [t0 − τ, ∞). We shall show that all positive solutions of ( * ) can be classified into four types, A, B, C, and D, and we shall obtain sufficient and necessary conditions for the existence of A-type, B-type, and D-type positive solutions of ( * ), respectively. A sufficient condition for the existence of C-type positive solutions of ( * ) is also given. Finally, we shall offer a sharp oscillation result for all solutions of ( * ). Our results generalize and improve those established in B. Yang and B. G. Zhang (Funkcial. Ekvac.39 (1996), 347–362). 相似文献
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