Antioxidant activities and total phenol content of Inula viscosa extracts selected from three regions of Morocco

Objective:To investigate antioxidant activity,total phenolic and flavonoid content of ethanol(E) and ethyl acetate(A) extracts of Inula viscosa aerial parts selected from three regions of Morocco(Imouzzer.Sefrou and Taounate).Methods:Antioxidants properties were measured by three different test systems of assay namely free radical scavenging activities against 2,2-diphenyI-1-picrylhydrazyl,total antioxidant capacity and iron-reducing capacity.Total phenolic content was measured by FolinCiocalteu reagent.Results:All the extracts showed significant antioxidant activities and contained important levels of phenols.The ethanol extract(0.3 mg/mL) from Sefrou showed the greatest antioxidant capacity in the three systems of assay,which was probably due to its high content of polyphenols(274.39±6.94) mg gallic acid equivalent/g dry extract.Total flavonoid content was found equal for all extracts.Conclusions:Our results of antioxidant assays were justified and partially supported the popular usage of the tested plants.The high antioxidant activity found in the plant from Sefrou and its great biomass in this region suggested that Inula viscosa is a good source of natural antioxidants compounds which might have benefits for health.

First-principles calculations to investigate structural,electronic,magnetic,optical and thermodynamic properties of RE_(2)Rh_(3)Ge(RE=Pr,Sm)

In this paper,we analyzed the physical characteristics of the ternary alloys RE_(2)Rh_(3)Ge(RE=Pr and Sm)using the first principles calculation based on functional density theory integrated in the Wien2k code.The calculated formation energies of Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are−5.3827 and−5.2782 eV/atom,respectively,showing that these alloys may exist stably.The results of the band structure and density of states indicate that all of the compounds tested are magnetic metals,and their magnetism is mostly related to the contribution of Pr and Sm atoms.The total magnetic moments of Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are 4.07245 and 11.16161μB/f.u,respectively.Thermodynamic parameters such as heat capacity at constant pressure,entropy,Debye temperature,lattice volume,compressibility coefficients,and Grüneisen parameter alloys were calculated using the Gibbs algorithm and studied in depth over a large temperature range of 0-900 K.The Debye temperature increases with increasing pressure and decreases with decreasing temperature.Moreover,the Debye temperatures calculated at p=0 GPa and T=300 K are equal to be 342 and 322 K for Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge,respectively.The optical characteristics such as the real and imaginary portions of the dielectric function,the absorption coefficient,the energy-loss function,and the refractive index were investigated and discussed in more depth.

Structural,microstructural and dielectric properties of Ba_(1-x)La_(x)Tie_(1-x/4)O_(3)prepared by sol gel method

Detailed structural and dielectric properties of Lanthanum-doped barium titanate Ba_(1-x)La_(x)Tie_(1-x/4)O_(3)ceramic powders BLTx(where x=0:00;0.10;0.20;0.30 and 0.40)/BT,BLT10,BLT20,BLT30 and BLT40,synthesized by the sol gel process,calcined at 900℃for 3 h and sintered at 1250○C for 6 h,have been investigated.The phase formation and crystal structure of the samples were checked by X-ray diffraction(XRD)and Raman spectroscopy.The samples crystallize in the pure perovskite structure that transforms from tetragonal to pseudocubic under doping with La;results that have been confirmed by Rietveld Refinement technique.The estimated average crystallite size of the samples was about 23 nm.Dielectric parameters(dielectric permittivity and losses)were determined in the temperature range room temperature(RT)-280℃and in the frequency range 500 Hz-2 MHz.La doping gives rise to a strong decrease of the ferro-to-paraelectric transition temperature,and the frequency dependence of the permittivity shows that the samples with x=0.00 and x=0.10 reach their resonance frequency.The frequency dependence of impedance and electric modulus properties were studied over a wide frequency range from 1 kHz to 2MHz at various temperatures to confirm the contributions from grains and grain-boundaries.The complex impedance analysis data have been presented in the Nyquist plot which is used to identify the corresponding equivalent circuit and fundamental circuit parameters;it was found that the grain boundaries resistance is dominant at room temperature.The frequency dependence of the parameters permittivity,losses and AC conductivity reveals that the relaxation process is of the Maxwell-Wagner type of interfacial polarization.

A novel CMOS charge-pump circuit with current mode control 110mA at 2.7V for telecommunication systems

This paper presents a novel organization of switch capacitor charge pump circuits based on voltage doubler structures. Each voltage doubler takes a DC input and outputs a doubled DC voltage. By cascading voltage doublers the output voltage increases up to 2 times. A two-phase voltage doubler and a multiphase voltage doubler structures are discussed and design considerations are presented. A simulator working in the Q-V realm was used for simplified circuit level simulation. In order to evaluate the power delivered by a charge pump, a resistive load is attached to the output of the charge pump and an equivalent capacitance is evaluated. To avoid the short circuit during switching, a clock pair generator is used to achieve multi-phase non-overlapping clock pairs. This paper also identifies optimum loading conditions for different configurations of the charge pumps. The proposed charge-pump circuit is designed and simulated by SPICE with TSMC 0.35-μm CMOS technology and operates with a 2.7 to 3.6 V supply voltage. It has an area of 0.4 mm^2; it was designed with a frequency regulation of 1 MHz and internal current mode to reduce power consumption.

Existence of Renormalized Solutions for Nonlinear Parabolic Equations

We give an existence result of a renormalized solution for a class of nonlin- ear parabolic equations b（x,u）/ t-div （a（x,t,u, u））＋g（x,t,u,u ）＋H（x,t, u）=f,in QT, where the right side belongs to LP＇ （0,T;W-1,p＇（Ω）） and where b（x,u） is unbounded function of u and where - div （ a （ x, t, u, u） ） is a Leray-Lions type operator with growth ｜u ｜p- 1 in V u. The critical growth condition on g is with respect to u and no growth condition with re sp ect to u, while the function H （x, t, u） grows as｜ u ｜p - 1.