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101.
102.
《Mathematical Methods in the Applied Sciences》2018,41(1):386-406
We address the question of mean biomass volumetric productivity optimization, which originates from the simplification of dynamics of microalgae in a batch bioreactor process with light incidence. In particular, the stability of the model is analyzed, some optimality necessary conditions for the nonsmooth optimization problem obtained through the inclusion of different photoperiods are studied, and the model is applied in the particular case of Chlamydomonas reinhardtii microalgae to validate our results. 相似文献
103.
Based on the cure characteristics of the Natural Rubber/Sulfur/N–t–butylbenzothiazole– 2–sulfenamide (NR/S/TBBS) system, a kinetic model with induction, curing, and overcure periods was chosen to simulate the cure reaction of this system. Cure-curves reflecting the development of torque were recorded as a function of cure time for NR compounds by a rubber processing analyzer. The cure curves were then non-linear fitted. The results show that the simulated curves fit well with the experimental curves. Rate constant K 2 for formation of activated crosslink precursors is much higher than rate constant K 6 for crosslink degradation under the same cure condition. Reaction activation energy E 2 and E 6 calculated from K 2 and K 6 through the Arrhenius equation showed that E 6 is higher than E 2. The increase of sulfur dosage led to the decrease of E 6 and E 2, but E 6 decreased more evidently. 相似文献
104.
105.
J. Belmonte‐Beitia 《Mathematical Methods in the Applied Sciences》2013,36(8):974-982
The dark soliton solutions corresponds to certain heteroclinic orbits for related autonomous planar differential equations. In this paper, we give a proof of the existence of upper and lower bounds of these heteroclinic orbits and find these bounds of explicit form. We put it into practice for a particular case of the derivative nonlinear Schrödinger equation. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
106.
Novel optical orthogonally modulation scheme for superimposing DPSK signals on dark RZ signals 总被引:1,自引:0,他引:1
Yufeng Shao Yaoqiang Xiao Lili Cheng Huiwen Xu Yazhi Pi 《Optics Communications》2008,281(14):3658-3667
A configuration of transmitter for superimposing DPSK signals on dark RZ signals was proposed. The transmitter comprises two optical phase modulators and a delayed line Mach-Zehnder interferometer. A new orthogonally modulation format with tunable duty cycle and extinction ratio in the optical domain was generated and discussed. The results show that the proposed modulation format offers significant advantages in offering high spectral efficiency values, high extinction ratio, and requiring electronics with reduced bandwidth. 相似文献
107.
QIAO Qing-Peng TANG Jian LI Xue-Qian 《理论物理通讯》2008,50(11):1211-1218
Following previous study, in the littlest Higgs model (LHM), the heavy photon is supposed to be a possiL dark matter candidate and its relic abundance of the heavy photon is estimated in terms of the Boltzman- Lee-Weinba time-evolution equation. The effect of the T-parity violation is also considered. Our calculations show that when Higmass MH taken to be 300 GeV and do not considering T-parity violation, only two narrow ranges 133 〈 MAH 〈 135 Ge and 167 〈 MAH〈 169 GeV are tolerable with the current astrophysical observation and if 135 〈 MAH 〈 167 GeV there must at least exist another species of heavy particle contributing to the cold dark matter. As long as the T-pari; can be violated, the heavy photon can decay into regular standard model particles and would affect the dark matt abundance in the universe, we discuss the constraint on the T-parity violation parameter based on the present dat Direct detection prospects are also discussed in some detail. 相似文献
108.
109.
Veronika Barii Milica Cvijeti Stokanovi Ivana Flanjak Kristina Doko Antun Jozinovi Jurislav Babi Drago ubari Borislav Mili
evi Ines Cindri urica A
kar 《Molecules (Basel, Switzerland)》2020,25(22)
Chocolate is considered as both caloric and functional food. Its nutritional properties may be improved by addition of fiber; however, this may reduce polyphenols content. The aim of this research was to determine the influence of cocoa shell addition (as a source of fiber) and its combination with different ingredients (cocoa butter equivalents (CBE), emulsifiers, dairy ingredients) on polyphenols of dark and milk chocolates. Total polyphenol (TPC) and total flavonoid (TFC) contents were determined spectrophotometrically, identification and quantification of individual compounds by high pressure liquid chromatography and antioxidant capacity by ferric reducing antioxidant power (FRAP) assay. Results showed that even though addition of cocoa shell to chocolate results in reduced contents of TPC, TFC, and individual compounds, it is not significant compared to ones reported by other authors for commercial chocolates. Other ingredients influence determined values for all investigated parameters; however, additional research is needed to reveal exact mechanisms and implications. 相似文献
110.
In this paper, two novel bismaleimide resins based on 9, 9-bis[4-(4-maleimidophenoxy) phenyl] fluorene (PFBMI), 9, 9-bis[4-(4-maleimidophenoxy)-3-methylphenyl]fluorene (MFBMI), and 2, 2’-diallyl bisphenol A (DABPA) were prepared. Their curing mechanism and curing kinetic were carefully investigated by Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The thermal mechanical properties of the composites based on these BMI resins and the glass cloth were obtained by Dynamic mechanical analysis (DMA), displaying that the novel resins whose Tg were 296°C and 289°C had excellent thermal performance. In addition, Thermogravimetric analysis (TGA) results showed that both the cured PD and MD resins possessed good thermal stability, and their T5% were all higher than 410°C. 相似文献