检索结果-南通市图书馆

Evaluation of androgenic activity of Zingiber officinale and pentadiplandra brazzeana in male rats

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2002年第4期4卷 299-301页

作者： pierreKamtchouing GisèleYolandeMbongueFandio ThéophileDimo Hermine boukeng Jatsa Laboratoire de physiologie Animale Faculté des Sciences Université de Yaoundé I B.P.812 Yaoundé CamerounLaboratoire de Physiologie Animale Faculté des Sciences Université de Yaoundé I B.P.812 Yaoundé CamerounLaboratoire de Physiologie Animale Faculté des Sciences Université de Yaoundé I B.P.812 Yaoundé CamerounDépartement de Biologie et de Physiologie Animales Faculté des Sciences Université de Douala B.P. 24157 Douala Cameroun

Aim: Aqueous extracts of Zingiber officinale and pentadiplandra brazzeana were tested for their possible androgenic activity in male Wistar rats. Methods: The aqueous extracts of the two plants were gavaged separately to 2 groups of rats at a similar dose of 600 ***^***-1 for 8 days. At the end of the treatment, the animals were killed and the blood, testis, epididymis, seminal vesicles and prostate were collected for biochemical analysis. Results: The aqueous extract of Z. officinale significantly increased in the relative weight of the testis, the serum testosterone level, testicular cholesterol level and epididymal α-glucosidase activity. The aqueous extract of p. brazzeana significantly increased the weights of the testis, seminal vesicles and prostate. It also significantly increased the serum and testicular testosterone level. The fructose, α-glucosidase and cholesterol levels in p. brazzeanatreated rats were increased by 28%, 35% and 114%, respectively. Conclusion: The aqueous extracts of both p. brazzeana and Z. officinale have an androgenic activity, which seems to be more potent with p. brazzeana than with Z. officinale. (Asian J Androl 2002 Dec; 4: 299-301)

关键词： p. brazzeana Z. officinale testosterone androgenic activity

Theoretical prediction of structural,electronic and optical properties of quaternary alloy Zn_(1-x)be_xS_ySe_(1-y)

在线全文

学校读者我要写书评

暂无评论

Chinese physics b 2012年第3期21卷 321-327页

作者： Hacini K Meradji H Ghemid S El Haj Hassan F Laboratoire LpR D'epartement de PhysiqueFaculté des SciencesUniversité de Annaba Laboratoire de physique des Matériaux Faculté des SciencesUniversité Libanaise

Within density functional theory based on the full potentiM-linearized augmented plane wave method, we carry out the first-principles calculation of the structural, electronic, and optical properties of the zinc blende quaternary alloy Zn1-xbexSySe1-y. The perdew-burke-Ernzerhof generaized gradient approximation based on the optimization of total energy and the Engel-Vosko generalized gradient approximation based on the optimization of the corresponding potential are used. Our investigation on the effect of the composition on lattice constants, bulk modulus, band gap, optical dielectric constant, and refractive index shows a non-linear dependence. The energy gap Eg（x, y） has been determined over the entire compositions x and y. In addition, the energy band gap of the technologically important quaternary alloy Znl-xbexSySe1-y in conditions of being lattice matched to ZnS substrate has been investigated. It is noteworthy that the present work is the first theoretical study of the quaternary alloy of interest.

关键词： density functional theory full potential-linearized augmented plane wave method qua-ternary alloy lattice-matched substrate

New materials based on carbazole for optoelectronic device applications:Theoretical investigation

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2008年第4期19卷 488-492页

作者： K.Hasnaoui H.Zgou M.Hamidi M.bouachrine Unité de Recherche sur les Macromolécules et Modélisation Faculté des Sciences et TechniquesB.P.509 Boutalamine5200 ErrachidiaMorocco Unité de Chimie Théorique AppiquéeFaculté des Sciences et TechniquesB.P.509 Boutalamine5200 ErrachidiaMorocco Unité de Chimie Théorique Appliquée Faculté des Sciences et TechniquesB.P.509 Boutalamine5200 ErrachidiaMorocco Unité de Recherche sur les Macromolécules et Modélisation Faculté des Sciences et TechniquesB.P.509 Boutalamine5200 ErrachidiaMorocco

A quantum-chemical investigation on the structural and optoelectronic properties of two materials based on carbazole is carried *** purpose is to display the effect of grafting the fluorine atoms on their optoelectronic and physico-chemical *** addition to solubility in the polar solvents and the modification in geometric parameters,the substitution of fluorine destabilizes the HOMO and LUMO levels,decreases the band gap energy and raises conjugation *** properties suggest the substituted fluorine compound as a good candidate for optoelectronic applications.

关键词： Conjugated polymers DFT theoretical investigation Carbazole Optoelectronic applications

Theoretical study of structural and electronic properties of oligo(thiophene-phenylene)s in comparison with oligothiophenes and oligophenylenes

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2008年第1期19卷 123-126页

作者： H.Zgou S.M.bouzzine S.bouzakraoui M.Hamidi M.bouachrine Unité de Recherche sur les Macromolécules et Modélisation Faculté des Sciences et TechniquesB.P.509 Boutalamine5200 ErrachidiaMorocco Unité de Chimie Théorique AppliquéeFaculté des Sciences et TechniquesB.P.509 Boutalamine5200 ErrachidiaMorocco Unité de Chimie Théorique Appliquée Faculté des Sciences et TechniquesB.P.509 Boutalamine5200 ErrachidiaMorocco Unité de Recherche sur les Macromolécules et Modélisation Faculté des Sciences et TechniquesB.P.509 Boutalamine5200 ErrachidiaMorocco

In this work, a quantum-chemical investigation on the structural and opto-electronic properties of oligo（thiophene-phenylene）（4Tp） is carried out. The results are discussed in comparison with the properties of corresponding oligothiophene （8T） and oligophenylene （8p）. As the opto-electronic properties of this type of conducting polymers are governed by their electronic band gap, we shall also present a comparison among HOMO, LUMO and band gap energies of these three materials.

关键词： Conjugated polymers Oligothiophene Oligophenylene Oligo(thiophene-phenylene) DFT

Existence of T-solution for Degenerated problem via Minty's Lemma

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2008年第3期24卷 431-438页

作者： Y.AKDIME E.AZROUL M.RHOUDAF Département de Mathématiques et Informatique facultédes sciences Dhar-Mahraz b. p 1796 Atlas Fès Maroc

We study the existence result of solutions for the nonlinear degenerated elliptic problem of the form, -div（a（x, u,△↓u）） = F in Ω, where Ω is a bounded domain of R^N, N≥2, a ：Ω×R×R^N→R^N is a Carathéodory function satisfying the natural growth condition and the coercivity condition, but they verify only the large monotonicity. The second term F belongs to W^-1,p′（Ω, w^＊）. The existence result is proved by using the L^1-version of Minty＇s lemma.

关键词： weighted Sobolev spaces truncations L^1-version of Minty's lemma

Energy calibration of laterally segmented electromagnetic calorimeters based on neutral pion detection

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2017年第11期28卷 164-171页

作者： Malek Mazouz faculté des sciences de Monastir 5000 Monastir Tunisia

This paper describes a method for energy calibration of laterally segmented electromagnetic calorimeters based on the detection of two-photon decays of π~0 *** calibration procedure performs a X^2 function minimization between the measured π~0 energy in the calorimeter and its expected energy deduced from the π~0 momentum direction. The performance of this technique is demonstrated with a Monte Carlo simulation of an experimental case where biased calibration coefficients are employed. The real calibration coefficients are restored with less than 1% relative accuracy when a sufficient number of π~0 is detected. This technique is applied to monitor daily the calibration coefficients of the calorimeter used in the Jefferson Lab Hall A DVCS experiments.

关键词： Electromagnetic calorimeters Energy calibration Detector modeling and simulations Data processing methods

Enhancing optical absorption in visible light of ZnO co-doped with europium and promethium by first-principles study through modified becke and Johnson potential scheme

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2019年第4期37卷 416-421页

作者： A.G.El Hachimi M.L.Ould NE A.El Yousfi A.benyoussef A.El Kenz Laboratory of Condensed Matter and Interdisciplinary sciences (LaMCScI) Associé Au CNRST (URAC 12) Département de Physique B.P.1014 Faculté des SciencesUniversité Mohammed V Hassan Ⅱ Academy of Science and Technology

by using first-principles calculations we studied the electronic, optical and magnetic properties of ZnO co-doped with Eu and pm. In this calculation, we used Wien2 k code based on full potential linearized augmented plane waves(Fp-LApW) method with the modified becke-Johnson(mbJ) approximation. This correction gives good band gap compared to experimental band gap. The introduction of Eu and pm codoping leads to an increase in the band gap. Electrons can transit easily from the valence band to the conduction band, which results in an enhancement of visible light absorption in a wider absorption range. Absorption spectra reach a high value in visible and infrared light regions. With the significance of the obtained results, the studied compounds may potentially find spintronic and optoelectronic applications.

关键词： Zinc oxide Rare earth Density functional theory Modified becke-Johnson Magnetic properties Spintronics

An investigation of merging and diverging cars on a multi-lane road using a cellular automation model

在线全文

学校读者我要写书评

暂无评论

Chinese physics b 2012年第11期21卷 565-572页

作者： K.Jetto H.Ez-Zahraouy A.benyoussef Laboratoire de Magnétisme et de la physique des Hautes Energies Universit'e Mohammed V Faculté des Sciences Ecole Hassania des Travaux publics KM 7 Route DEL JADIDAB.P 8108OasisCasablancaMaroc

In this paper, we have investigated two observed situations in a multi-lane road. The first one concerns a fast merging vehicle. The second situation is related to the case of a fast vehicle leaving the fastest lane back into the slowest lane and targeting a specific way out. We are interested in the relaxation time T, i.e., which is the time that the merging （diverging） vehicle spends before reaching the desired lane. Using analytical treatment and numerical simulations for the NaSch model, we have found two states, namely, the free state in which the merging （diverging） vehicle reaches the desired lane, and the trapped state in which T diverges. We have established phase diagrams for several values of the braking probability. In the second situation, we have shown that diverging from the fast lane targeting a specific way out is not a simple task. Even if the diverging vehicle is in the free phase, two different states can be distinguished. One is the critical state, in which the diverging car can probably reach the desired way out. The other is the safe state, in which the diverging car can surely reach the desired way out. In order to be in the safe state, we have found that the driver of the diverging car must know the critical distance （below which the way out will be out of his reach） in each lane. Furthermore, this critical distance depends on the density of cars, and it follows an exponential law.

关键词： traffic flow merging and diverging area intelligent transportation system cellular au-tomation

Computer modelling and analysis of the photodegradation effect in a-Si:H p–i–n solar cell

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2015年第1期36卷 52-59页

作者： A.F bouhdjar L.Ayat AM.Meftah N.Sengouga AF.Meftah faculté des sciences Laboratoire des Matériaux Semi-conducteurs et Métalliques Université Mohammed Khider B.P. 145Biskra 07000 Algérie Laboratory of Semiconductor Devices physics Physics Department University of Béchar P.O. Box 417 Béchar 08000Algeria

Using a previous model, which was developed to describe the light-induced creation of the defect density in the a-Si：H gap states, we present in this work a numerical modelling of the photodegradation effect in the a-Si：H p–i–n solar cell under continuous illumination. We first considered the simple case of a monochromatic light beam with a wavelength λ between 530–540 nm non uniformly absorbed, then the global standard solar spectrum（AM1.5） illumination is taken into account. The photodegradation is analysed on the basis of the resulting changes in the free carrier＇s densities, recombination rate, band structure, electrical potential and field, space charge, and current densities. Changes in the cell＇s external parameters： the open circuit voltage Voc, the short circuit current density Jsc, the fill factor FF and the maximum power density pmaxare also presented.

关键词： a-Si:H Staebler–Wronski effect p–i–n