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61.
Synthesis of 1, 4, 5, 6-Tetrahydro 2-methyl 4-pyrimidine carboxylic acid (Ectoïne) is achieved by thermal cyclization of N-Acetyl diaminobutyric acid, itself synthesized by acetylation of (L) 2,4-diaminobutyric acid. 相似文献
62.
Souad A. M. Al-Chalabi Alan R. Jones 《Particle & Particle Systems Characterization》1994,11(3):200-206
A mathematical model is described to predict Fraunhofer diffraction by statistically irregular particles. It is demonstrated that the particles are characterised by a probability distribution of radius and a correlation function in the surface. The results of calculation show that at angles not too far from the forward scattering direction and for irregularity heights within a limited range, the irregular particles may be represented approximately by spheres with a size distribution equal to the probability distribution of radius. However, the calculations are highly sensitive to the exact nature of the probability functions. Comparisons of the results with those of a simpler model are not satisfactory beyond the first forward scattering lobe. 相似文献
63.
Soumia Ramdani Amina Amar Kamal Belhsaien Souad El Hajjaji Said Ghalem Abdelmjid Zouahri 《Analytical letters》2018,51(15):2468-2487
In Algeria, few studies have been conducted on the evaluation of roadside soil pollution. A total of 34 soil samples (28 roadside and 6 off-road) was obtained at 0–20?cm depth along the RN 35 national road. Heavy metal (Cd, Cr, Cu, Fe, Ni, Pb, and Zn) contents were extracted using aqua regia digestion and determined using atomic absorption spectrometry. Background values of heavy metal contents were determined using the robust statistical method of median plus two times the median absolute deviation. Single- and multi-element pollution and ecological risk indices were calculated. The results showed that background values were 2.5?±?0.3, 64.9?±?8.1, 28.0?±?4.1, 29371.5?±?4403.0, 32.9?±?4.4, 72.2?±?12.8, and 445.1?±?62.9?mg/kg for Cd, Cr, Cu, Fe, Ni, Pb, and Zn, respectively. The results were all higher than their corresponding median values. Single-element pollution indices (enrichment factor and geoaccumulation index) showed that the pollution is primarily due to Pb and Zn. Multi-element pollution index (Nemerow index) indicated that only 3% of the soil samples are strongly contaminated, whereas 23% are seriously contaminated. The potential ecological risk index showed that Cd is the most harmful element, followed by Pb and Zn. 65% of the soil samples had moderate potential ecological risk, while only 3% had considerable potential ecological risk. This study may be used as a baseline for future monitoring and as a tool for decision-making regarding environmental protection policies and sustainability of this semiarid agroecosystem. 相似文献
64.
Souad Rakass Hicham Oudghiri Hassani Ahmed Mohmoud Fethi Kooli Mostafa Abboudi Eman Assirey Fahd Al Wadaani 《Molecules (Basel, Switzerland)》2021,26(5)
Removing methylene blue (MB) dye from aqueous solutions was examined by the use of nickel molybdate (α-NiMoO4) as an adsorbent produced by an uncomplicated, rapid, and cost-effective method. Different results were produced by varying different parameters such as the pH, the adsorbent dose, the temperature, the contact time, and the initial dye concentration. Adsorbent dose and pH had a major removal effect on MB. Interestingly, a lower amount of adsorbent dose caused greater MB removal. The amount of removal gained was efficient and reached a 99% level with an initial methylene blue solution concentration of ≤160 ppm at pH 11. The kinetic studies indicated that the pseudo-second-order kinetic model relates very well with that of the obtained experimental results. The thermodynamic studies showed that removing the MB dye was favorable, spontaneous, and endothermic. Impressively, the highest quantity of removal amount of MB dye was 16,863 mg/g, as shown by the Langmuir model. The thermal regeneration tests revealed that the efficiency of removing MB (11,608 mg/g) was retained following three continuous rounds of recycled adsorbents. Adsorption of MB onto α-NiMoO4 nanoparticles and its regeneration were confirmed by Fourier transform infrared spectroscopy (FTIR) analysis and scanning electron microscopy (SEM) analysis. The results indicated that α-NiMoO4 nanosorbent is an outstanding and strong candidate that can be used for removing the maximum capacity of MB dye in wastewater. 相似文献
65.
Mohsen K. A. Regal Safa S. Shaban Souad A. El‐Metwally 《Journal of heterocyclic chemistry》2019,56(1):226-233
5‐Amino‐thieno[3,2‐c]pyrazole derivative 2 was prepared by Gewald reaction in a one‐pot procedure. The amino group of compound 2 like primary aromatic amine formed the diazonium salt when treated with NaNO2/HCl, followed by coupling with different nucleophiles to yield the azo coupling products 3a – d . The reactivity of 5‐amino‐thienopyrazole 2 has been investigated towards different electrophilic reagents such as aromatic aldehydes, alkyl halide, acid chloride, acid anhydride, phenyl isothiocyanate, carbon disulfide, ethyl glycinate, and thioacetamide, which afforded the reaction products 4 – 14 , respectively. 相似文献
66.
Mohamed Hachi Ahmed Slimi Asmae Fitri Souad ElKhattabi Adil Touimi Benjelloun Mohammed Benzakour 《Molecular physics》2020,118(8)
ABSTRACTThis study aims to evaluate the characteristics of novel organic D-π-A-π-D class small-molecules by using carefully the density functional theory, and time-dependent density functional theory calculations. Thedesigned sequence of (D-A) BHJ-1a to BHJ-4a in organic Bulk Heterojunction (BHJ) solar cells has been comprehensively analysed. Thiéno[2,3-b]indole (TI) has been used as donor, and Diketopyrrolopyrrole (DPP) as acceptor for all compounds. In order to improve the electronic, photovoltaic, and opticalproperties, we have substituted thiophene unit with furan, thieno[2,3-b]thiophene, thiazole and thiazolothiazole as π-bridge moieties. Thus, the result shows that the wise choice of the π-bridge units plays a significant role in improving Egap, producing a high bathochromic shift, and increasing VOC as well as a theoretical power conversion efficiency (PCE) over 7%. Interestingly, BHJ-4a with suitable π-bridge presents the optimal electronic properties with low band gap (1.870?eV) and high VOC (1.534?eV). Furthermore, we have modelled a Bulk heterojunction organic photovoltaic cells based on donor-PCBM complex in order to achieve the optimum Egap and VOC. Consequently, the obtained results provide a new way to design BHJ small molecule donors with higher power conversion efficiency. 相似文献
67.
Ghyati Souad Kassou Said El Jai Mostapha El Kinani El Hassan Benhamou Mabrouk Chang Sheng Hsiung 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7213-7228
Journal of Thermal Analysis and Calorimetry - Polymer/clay-based composites were prepared via solution intercalation method using natural clay and poly (ethylene) glycol (PEG4000) as organic... 相似文献
68.
69.
Hartmut Schnberg Souad Boulmaz Michael Wrle Lorenz Liesum Arthur Schweiger Hansjrg Grützmacher 《Angewandte Chemie (International ed. in English)》1998,37(10):1423-1426
A pocket suitable for bonding transition metals is formed by the 5-phosphanyl group and the olefinic unit of the central seven-membered ring, which has a rigid boat conformation, of the ligand troppPh ( 1 ). This new ligand system allows the synthesis and isolation of stable d9 and d10 rhodium complexes 2 and 3 , respectively. 相似文献
70.
Soukaina Foulal Souad El Hajjaji Laszlo Trif Abdelaziz Sabbar Imane Chtioui Dominique De Caro Christophe Faulmann Pascale De Caro 《Journal of Thermal Analysis and Calorimetry》2017,127(3):1879-1888
Nanoparticles of two molecule-based conductors, namely TTF·TCNQ and TTF[Ni(dmit)2]2, have been prepared in organic solution in the presence of ionic or nonionic species bearing a long-chain alkyl group, acting as growth-controlling agents. The size, morphology, and state of dispersion of the nanoparticles depended on the nature of the growth-controlling agent and the reaction temperature. In the presence of a long-chain alkyl-based ionic liquid at ?50 °C, electron micrographs evidence that TTF·TCNQ nano-objects are frequently elongated, whereas TTF[Ni(dmit)2]2 nanoparticles are aggregated. In the presence of a neutral long-chain alkyl-based imine at room temperature, nanoparticles are spherical (mean diameter <20 nm) and well dispersed. Vibration spectra evidence that the amounts of charge transfer for TTF·TCNQ and TTF[Ni(dmit)2]2 as nano-objects are very similar to those for the same phases as bulk materials. According to the thermoanalytical investigations, the prepared nanoparticles are stable thermally up to approximately 200 °C, and their decomposition is generally a multi-step process. Their heat treatment results in various sulfur-containing volatiles (CS2, SO2, H2S); moreover, HCN is also detected in the case of nitrogen-containing molecules (TCNQ). 相似文献