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排序方式: 共有132条查询结果,搜索用时 15 毫秒
101.
E. H. EL Kinani 《International Journal of Theoretical Physics》2000,39(6):1457-1462
We review the R-deformed Heisenberg algebra and its Fock space representation.We construct the R-deformed quantum mechanics in N dimensions, and proposea new R-deformed Virasoro algebra. 相似文献
102.
103.
Nor EL Houda Tahiri Hamza Saghrouchni Noureddine Hamamouch Mostafa El Khomsi Abdulhakeem Alzahrani Ahmad Mohammad Salamatullah Lyoussi Badiaa Lalla Aicha Lrhorfi 《Molecules (Basel, Switzerland)》2022,27(23)
During the postharvest period, citrus fruits are exposed to Penicillium italicum, Penicillium digitatum, and Geotrichum candidum. Pesticides such as imazalil (IMZ), thiabendazole (TBZ), orthophenylphenol (OPP), and guazatine (GUA) are commonly used as antifungals. Glyphosate (GP) is also used in citrus fields to eliminate weed growth. The sensitivity of fungal pathogens of citrus fruit to these pesticides and 1,8-cineole was evaluated, and the effect of GP on the development of cross-resistance to other chemicals was monitored over a period of 3 weeks. IMZ most effectively inhibited the mycelial growth and spore germination of P. digitatum and P. italicum, with minimum inhibitory concentrations (MICs) of 0.01 and 0.05 mg/mL, respectively, followed by 1,8-cineole, GP, and TBZ. 1,8-Cineole and GP more effectively inhibited the mycelial growth and spore germination of G. candidum, with minimum inhibitory concentrations (MICs) of 0.2 and 1.0 mg/mL, respectively, than OPP or GUA. For the spore germination assay, all substances tested showed a total inhibitory effect. Subculturing the fungal strains in culture media containing increasing concentrations of GP induced fungal tolerance to GP as well as to the fungicides. In soil, experiments confirmed that GP induced the tolerance of P. digitatum to TBZ and GP and the tolerance of P. italicum to IMZ, TBZ, and GP. However, no tolerance was recorded against 1,8-cineole. In conclusion, it can be said that 1,8-cineole may be recommended as an alternative to conventional fungicides. In addition, these results indicate that caution should be taken when using GP in citrus fields. 相似文献
104.
N. Ben Afkir E. Feddi J. Meziane Y. EL Kouari M. Zazoui A. Migalska-Zalas 《Opto-Electronics Review》2019,27(1):25-31
The impact ionization in semiconductor materials is a process that produces multiple charge carrier pairs from a single excitation. This mechanism constitutes a possible road to increase the efficiency of the p-n and p-i-n solar cells junctions. Our study considers the structure of InN/InGaN quantum dot solar cell in the calculation. In this work, we study the effect of indium concentration and temperature on the coefficient of the material type parameter of the impact ionization process for a p(InGaN)-n(InGaN) and p(InGaN)-i(QDs-InN)-n(InGaN) solar cell. Next, we investigate the effect of perturbation such as temperature and indium composition on conventional solar cell’s (p(InGaN)-n(InGaN)) and solar cells of the third generation with quantum dot intermediate band IBSC (p(InGaN-i(QD-InN)-n(InGaN)) by analyzing their behaviour in terms of efficiency of energy conversion at the presence of the impact ionization process. Our numerical results show that the efficiency is strongly influenced by all of these parameters. It is also demonstrated that decreased with the increase of indium concentration and temperature which contributes to an overall improvement of the conversion efficiency. 相似文献
105.
TADAYOSHI MASUDA JOHN F. YANAGIDA JAMES E. T. MONCUR SAMIR A. EL‐SWAIFY 《Natural Resource Modeling》2010,23(1):22-47
Abstract In this paper, we develop a land use allocation model to search for the optimal ratio of organic (nonchemical) and conventional (chemical‐use) farming acreage. The idea is to incorporate stochastic production frontiers (SPFs) to a multi‐criteria decision making (MCDM) model as technological constraints. The objectives of this model are to maximize net returns, minimize chemical inputs, and optimize organic inputs given environmental and ecological concerns. The compromise solutions suggest the desirable ratio of organic and conventional farming acreage and targetable operations for each farming system to improve regional welfare. This method was applied to the Kona coffee belt, Hawaii, and the analysis determined the optimal proportion of organic and conventional Kona coffee farming fields as 0.265 to 0.735 in terms of optimizing community benefits or regional welfare. 相似文献
106.
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. 相似文献
107.
Mahmoud Mohamed A. M. El-Demerdash Safinaz H. Gogary Tarek M. EL El-Nahas Ahmed M. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2018,92(12):2476-2484
Russian Journal of Physical Chemistry A - Atmospheric oxidation of methyl propanoate (MP) by the OH radical has been performed using density functional theory (BMK, BBIK) and ab initio (MP2,... 相似文献
108.
LAILA H. ABDEL‐RAHMAN RAFAT M. EL‐KHATIB LOBNA A. E. NASSR AHMED M. ABU‐DIEF 《国际化学动力学杂志》2014,46(9):543-553
The reactivity of few novel high‐spin Fe(II) complexes of Schiff base ligands derived from 2‐hydroxynaphthaldehyde and some variety of amino acids with the OH? ion has been examined in an aqueous mixture at the temperature range from 10 to 40°C. Based on the kinetic investigations, the rate law and a plausible mechanism were proposed and discussed. The general rate equation was suggested as follows: rate = kobs[complex], where kobs. = k1 + k2[OH?]. Base‐catalyzed hydrolysis kinetic measurements imply pseudo–first‐order doubly stage rates due the presence of mer‐ and fac‐isomers. The observed rate constants kobs are correlated with the effect of substituent R in the structure of the ligands. From the effect of temperature on the rate base hydrolysis reaction, various thermodynamic parameters were evaluated. The evaluated rate constants and activation parameters are in a good agreement with the stability constants of the investigated complexes. Moreover, the reactivity of the investigated complexes toward DNA was examined and found to be in a good agreement with the reported binding constants. 相似文献
109.
Novel Synthesis of Some Imidazolyl‐, Benzoxazinyl‐, and Quinazolinyl‐2,4‐dioxothiazolidine Derivatives
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Ali M. Youssef Ahmed K. EL‐Ziaty Wael S. I. Abou‐Elmagd Sayed K. Ramadan 《Journal of heterocyclic chemistry》2015,52(1):278-283
2‐(2,4‐Dioxothiazolidin‐5‐yl)acetic acid 1 and its chloride derivative 2 were allowed to react with different aromatic amines such as o‐phenylenediamine, o‐aminothiophenol, p‐aminoacetophenone, and anthranilic acid to give the biologically active nuclei such as imidazoles, thiazoles, benzoxazines, and quinazolines incorporated with the thiazolidindione nucleus. The antimicrobial activity of five of the synthesized compounds was examined against one gram positive bacteria (Staphylococcus aureus), one gram negative bacteria (Escherichia coli), and two fungi (Aspergillus flavus and Candida albicans). Four compounds showed moderate antibacterial and antifungal activities. 相似文献
110.
Hafiz Muhammad Rashad Javeed Mazhar Ali Milan Skalicky Fahim Nawaz Rafi Qamar Atique ur Rehman Maooz Faheem Muhammad Mubeen Muhammad Mohsin Iqbal Muhammad Habib ur Rahman Pavla Vachova Marian Brestic Alaa Baazeem Ayman EL Sabagh 《Molecules (Basel, Switzerland)》2021,26(11)
Lipoic acid (LA) and melatonin (MT) are pleiotropic molecules participating in plant stress resistance by modulating cellular biochemical changes, ion homeostasis, and antioxidant enzyme activities. However, the combined role of these two molecules in counteracting the detrimental impacts of salinity stress is still unknown. In the present study, we determined the effects of exogenous LA (0.5 µM), MT (1 µM) and their combination (LA + MT) on growth performance and biomass accumulation, photosynthetic pigments, enzymatic and non-enzymatic antioxidant activities, and ions homeostatic in canola (Brassica napus L.) seedlings under salinity stress (0, 100 mM) for 40 days. The results indicate that exogenous application of LA + MT improved the phenotypic growth (by 25 to 45%), root thickness (by 68%), number of later lateral roots (by 52%), root viability (by 44%), and root length (by 50%) under salinity stress. Moreover, total soluble protein, chlorophyll pigments, the concentration of superoxide dismutase (SOD), catalase peroxidase (CAT), and ascorbic peroxidase (ASA) increased with the presence of salt concentration into the growth media and then decreased with the addition of LA + MT to saline solution. Leaf protein contents and the degradation of photosynthetic pigments were lower when LA + MT treatments were added into NaCl media. The proline and phenol contents decreased in the exogenous application of LA + MT treatments more than individual LA or MT treatments under the salinity stress. The incorporation of LA or MT or a combination of LA + MT to saline solution decreased salinity-induced malondialdehyde and electrolyte leakage. In conclusion, the alteration of metabolic pathways, redox modulation, and ions homeostasis in plant tissues by the combined LA and MT application are helpful towards the adaptation of Brassica napus L. seedlings in a saline environment. The results of this study provide, for the first time, conclusive evidence about the protective role of exogenous LA + MT in canola seedlings under salinity stress. 相似文献