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101.
Elyes Garoudja Walid Filali Slimane Oussalah Noureddine Sengouga Mohamed Henini 《半导体学报》2020,41(10):102401-102401-5
In this work, forward current voltage characteristics for multi-quantum wells Al0.33Ga0.67As Schottky diode were measured at temperature ranges from 100 to 300 K. The main parameters of this Schottky diode, such as the ideality factor, barrier height, series resistance and saturation current, have been extracted using both analytical and heuristics methods. Differential evolution (DE), particle swarm optimization (PSO) and artificial bee colony (ABC) have been chosen as candidate heuristics algorithms, while Cheung technic was selected as analytical extraction method. The obtained results show clearly the high performance of DE algorithms in terms of parameters accuracy, convergence speed and robustness. 相似文献
102.
Fadi Alakhras Emna Selmane Bel Hadj Hmida Ioannis Anastopoulos Zina Trabelsi Walid Mabrouk Noureddine Ouerfelli Jean François Fauvarque 《水科学与水工程》2021,14(1):36-45
In this study, the removal of monovalent and divalent cations, Na+, K+, Mg2+, and Ca2+, in a diluted solution from Chott-El Jerid Lake, Tunisia, was investigated with the electrodialysis technique. The process was tested using two cation-exchange membranes: sulfonated polyether sulfone cross-linked with 10% hexamethylenediamine (HEXCl) and sulfonated polyether sulfone grafted with octylamine (S-PESOS). The commercially available membrane Nafion® was used for comparison. The results showed that Nafion® and S-PESOS membranes had similar removal behaviors, and the investigated cations were ranked in the following descending order in terms of their demineralization rates: Na+ > Ca2+ > Mg2+ > K+. Divalent cations were more effectively removed by HEXCl than by monovalent cations. The plots based on the Weber–Morris model showed a strong linearity. This reveals that intra-particle diffusion was not the removal rate-determining step, and the removal process was controlled by two or more concurrent mechanisms. The Boyd plots did not pass through their origin, and the sole controlling step was determined by film-diffusion resistance, especially after a long period of electrodialysis. Additionally, a semi-empirical model was established to simulate the temporal variation of the treatment process, and the physical significance and values of model parameters were compared for the three membranes. The findings of this study indicate that HEXCl and S-PESOS membranes can be efficiently utilized for water softening, especially when effluents are highly loaded with calcium and magnesium ions. 相似文献
103.
E Rodriguez F Symoens P Mondon M Mallie MA Piens B Lebeau AM Tortorano F Chaib A Carlotti J Villard MA Viviani F Chapuis N Nolard R Grillot JM Bastide 《Canadian Metallurgical Quarterly》1999,48(2):181-194
This study investigated the source of infection and strain relatedness of Aspergillus fumigatus isolates from bronchial colonisation and invasive aspergillosis (IA) in four transplant patients. Environmental isolates from the patient's home and from the hospital and infecting isolates were obtained for patient A who developed IA. Clinic environmental and colonising isolates were obtained for patient B. Sequential isolates were obtained from various organs from patient C who developed IA and also from patient D who had a bronchitic aspergillosis that developed into IA. Ninety-one A. fumigatus isolates were analysed by three typing methods: multi-locus enzyme electrophoresis (MLEE), random amplified polymorphic DNA (RAPD) and sequence-specific DNA primers (SSDP). The three combined typing methods demonstrated a greater differentiation of isolates than the typing methods used separately or in pairs. This demonstrated the genotypic variability of A. fumigatus and facilitated better epidemiological analysis. Large polymorphisms were demonstrated for each patient isolate between and colonies within various samples. The relatedness of the isolates suggested nosocomially acquired aspergillosis for patient B, but the source of infection for patient A remained unclear. The results suggested at least three multiple infections among the four patients. This study enabled the identification of the source of infection and strain relatedness, which in turn facilitates the development of preventive measures for patient management in the future. 相似文献
104.
105.
This paper aims to define a control and management strategy for water pumping system which would be powered by a hybrid PV/diesel generator system with battery storage. The particularity of the proposed power management method is to ensure the water volume in need and to maximize the use of PV generator while limiting the use of the diesel generator. In order to capture the maximum power from PV generator, a fuzzy logic maximum power point tracking controller is applied. On the other hand, a PI regulator is used with a boost converter in order to adapt the voltage of the battery bank to the DC bus. The water flow of the pump is also controlled. The developed power management and control strategy has been implemented using SIMPOWER toolbox in Matlab/Simulink. The obtained satisfying simulation results prove the efficiency of the proposed solution that assures continuous supply of water and electricity. 相似文献
106.
Noureddine Benkeblia Patrick Varoquaux Barbara Gouble Ghalem Selselet‐Attou 《Journal of the science of food and agriculture》2000,80(12):1772-1778
The O2 and CO2 respiration rates of untreated and irradiated onion bulbs (Allium cepa) at 0.15 and 0.30 kGy were measured at 4, 10 and 20 °C. The O2 respiration rate increased for 24 h after treatment from 0.19 mmole kg−1 h−1 at 20 °C for control samples up to 0.26 and 0.39 mmole kg−1 h−1 for 0.15 and 0.3 kGy irradiated onions respectively. Respiratory quotient (RQ) increased with temperature. The Q10 of the respiration of the control samples (1.61) was lower than that of any other plant tissue, but it increased with storage duration and irradiation dose. The respiration rate of control onions increased steadily over 25 weeks of storage at 4 °C, while that of the irradiated samples decreased during the same period after a peak observed after irradiation treatment. The apparent Km for the Menten–Michaelis equation was determined on a new respirometer and averaged 1.6 kPa at 10 °C and 6.3 kPa at 20 °C. However, at this higher temperature (20 °C) apparent Km varied with O2 partial pressure, proving that the respiration of onion bulbs does not follow a Menten–Michaelis‐like process. The Fermentative Index (FI) of onions was measured under anoxic conditions as CO2 production rates in mmole kg−1 h−1 at 4, 10 and 20 °C. © 2000 Society of Chemical Industry 相似文献
107.
Mayouf Sellami Vincent Caignaert Meriem Hamdad Ahmed Bekka Noureddine Bettahar 《Journal of Alloys and Compounds》2009,482(1-2):13-18
A new pyrochlore solid solution with formula Bi1.5Sb1.5Cu1−xMnxO7 has been synthesized using ceramic method at 1000 °C. The cell parameter decreases linearly with increasing manganese concentration. Rietveld refinements for (B1.5Mn0.5)(Sb1.5Mn0.5)O7 compound using X-ray powder diffraction data confirmed an overall A2B2O7 cubic pyrochlore structure with a = 10.42749 (4) Å and Fd-3m symmetry. The reliability factors are Rwp = 3.48%; Rp = 2.37%; Rexp = 1.65% and RBragg = 1.58%. The magnetic susceptibility measurements achieved between 4 and 300 K indicate a paramagnetic behaviour with an oxidation state “2+” of the manganese ion. The electric resistance measured using complex impedance spectroscopy method put in evidence a decrease of the electric resistance with the temperature, which reached 5 × 102 Ω at 675 K. Dielectric properties depend on the variation of frequency and temperature, results indicate a conductive compound. 相似文献
108.
109.
Noureddine Benkeblia Patrick Varoquaux Norio Shiomi & Hideki Sakai 《International Journal of Food Science & Technology》2002,37(2):169-175
The effects of γ-irradiation, maleic hydrazide (MH) and carbamate isopropyl, N-phenyl (CIP) on the carbohydrate content, respiration rate (RR) sprouting and rotting of red onion bulbs ( Allium cepa L.) c.v. Rouge Amposta stored at 4, 10 and 20 °C were investigated. Between 6 and 8 weeks soluble sugars increased in concentration and varied between 6.0 and 6.5% fresh weight both at 10 and 20 °C. However, this peak did not exceed 6.0% fresh weight at 4 °C. The basal amount of soluble sugars was about 3% fresh weight. The content appeared to be influenced by temperature, with greater accumulation at 10 and 20 °C than at 4 °C. The RR increased when the bulbs sprouted, whereas it was reduced by the following treatments: irradiation, MH and CIP, the respiration of irradiated bulbs decreased during the final stage of storage because of the death of the sprouts. The chemical treatment used were effective in controlling sprouting of the bulbs during storage, although not as effective as irradiation and chilling. 相似文献
110.
A detailed theoretical treatment of a one- (1D) and three-dimensional (3D) photothermal deflection (PTD) technique is presented. Important effects of the probe beam size occur in PTD experiments when the radius of this beam is of the order of magnitude of the thermal diffusion length. The calculation of this effect is checked by experiments in paraffin oil at low modulation frequency as well as for 1D and for 3D. In this last case, we have considered two kinds of deflection: normal and transverse, and we have studied their variation for different values of the pump beam radius. The coincidence between theoretical and experimental curves confirms the validity of our theoretical model. 相似文献