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101.
Christopher J. Pillidge Lucy M. Sheehy Amal Shihata Zhao-Yan Pu Marian Dobos Ian B. Powell 《International Dairy Journal》2009,19(4):222-227
Partial 16S rRNA gene sequencing of Lactococcus lactis subsp. cremoris strains from our collection identified strains containing sequences diagnostic of both subspecies L. lactis subsp. lactis and L. lactis subsp. cremoris together in the same strain. The presence of a plasmid-encoded 16S rRNA pseudogene partly explained this result. Twenty-four out of 46 L. lactis subsp. cremoris strains tested by PCR contained this pseudogene. However, further analysis showed that five of these 24 strains also contained chromosomal 16S rRNA genes with sequences typical of L. lactis subsp. lactis. Genetic and phenotypic tests indicated these strains were otherwise normal L. lactis subsp. cremoris strains. Past recombination events between the 16S rRNA pseudogene and chromosomal 16S rRNA genes may explain this phenomenon. Genomic heterogeneity for both 16S rRNA and other gene sequences was observed for L. lactis subsp. cremoris SK11 from different laboratories, indicating caution is needed when integrating data from diverse sources for nominally the same strain. 相似文献
102.
Barkat Ali Khan Abid Farid Muhammad Rafique Asi Hamidullah Shah Amal Khattak Badshah 《Food chemistry》2009
A supervised trial was conducted in guava orchards during 2001 and 2002 to study residue dissipation rates of two organophos insecticides, trichlorfon and dimethoate at Kohat, NWFP, Pakistan. The insecticides were sprayed at recommended doses of 80 and 120 g a.i./100 l water on the fruits of guava when the fruits were semi ripe. The treated guava fruits were randomly sampled in triplicates (2 kg per field replicate) at 0, 3, 7, 14, and 21 days intervals after insecticide application. The samples were extracted in ethyl acetate and were cleaned up through Florisil column with ethyl acetate as eluent. The cleaned up extracts were analyzed for residues by HPLC method. The residues were found to have half-lives of 2.8–3.3 days for dimethoate and 1.7–2.0 days for trichlorfon. Based on the dissipation pattern of the insecticide residues in relation to their respective prescribed maximum residue limits, withholding periods of 3 and 9 days are suggested for guava after treatment with dimethoate and trichlorfon. 相似文献
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Amal Bouazizi Ghada Zaibi Abdul Basir Mounir Samet Abdennaceur Kachouri 《国际射频与微波计算机辅助工程杂志》2019,29(4)
In this paper, a meandered loop antenna, useful for medical cardiac monitoring application, more specifically, for heart beating close scrutiny is designed and experimentally tested. The proposed antenna is operating at the MICS band displays a high flexibility which allowing it to be curved easily around the heart's wall. In both, Simulation and measured results the antenna shows a sensitive nature any change introduced in heart's model size and would certainly bring about a noticeable shift in the antenna's resonant frequency. Linking the frequency variations taking place in concord with the heart movement turns out to stand as an effective key that provides extremely valuable information about the heart's activities. A correspondence between the obtained frequency variation linking with the change in size of the heart. In addition to the frequency response evaluation, the antenna characteristically displays an omni‐directional radiation pattern, which necessarily fits it for in‐body operation. 相似文献
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107.
Amal A. Hassan Faten H. Fahmy Abd El-Shafy A. Nafeh Mohamed A. Abu-elmagd 《国际可持续能源杂志》2017,36(6):545-562
The optimal design of renewable-based distributed generations (DGs) is a challenging issue in order to maximise their benefits and to overcome power quality problems. Therefore, this paper proposes a methodology for optimal allocation and sizing of renewable DG units to minimise total power losses over radial distribution systems. The planning problem is formulated as a single objective nonlinear mixed integer-constrained optimisation problem and is solved by using the augmented Lagrangian genetic algorithm (ALGA) by combining the objective function and the nonlinear constraints. In that case, the ALGA solves a sequence of sub-problems where the objective function penalises the constraints violation in order to obtain the best solution. The proposed technique is applied to IEEE radial test systems including 33-bus, 69-bus and 119-bus and is implemented with different scenarios including all possible combinations and various types of renewable DG units to prove the effectiveness of the proposed methodology. 相似文献
108.
Hamida Y. Mostafa Ebaa A. El-Shamy Amal S. Farag Nadia G. Kandile 《Egyptian Journal of Petroleum》2013,22(4):471-479
Neat ethylacetoacetate (EAA) and its mixtures with a co-solvent and an anti-solvent have been studied for refining of heavy wax distillate fraction to produce substantially non-carcinogenic base oil. The co-solvent and anti-solvent used are dipropylene glycol (DPG) and ethylene glycol (EG) respectively. The solubility characteristics of the main solvent and its mixed solvent systems were studied. Selection of the optimum solvent mixture and extraction variables has been studied. The effect of co-solvent and anti-solvent addition on the carcinogenic potential and raffinate quality has been determined under clearly comparable conditions. 相似文献
109.
Amal Elleuch Ahlem Boussetta Kamel Halouani Yongdan Li 《International Journal of Hydrogen Energy》2013
NiO-Samaria-Doped-Ceria (NiO-SDC) composite powders was synthesized by a traditional mechanical mixing process and tested as anode material for Direct Carbon Fuel Cell (DCFC), which uses almond shell biochar as fuel and molten carbonate-doped ceria composite as electrolyte. A three-layer pellet cell, viz. cathode (Lithiated NiO-SDC), composite electrolyte and anode (NiO-SDC) is fabricated by a die-pressing, screen printing and sintering method. 相似文献
110.
Devi Chandrasekhar Kakarla Krishna Murthy Jyothinagaram Amal Kumar Das Venimadhav Adyam 《Journal of the American Ceramic Society》2014,97(9):2858-2866
We have prepared polycrystalline R2NiMnO6 (R = Nd, Eu, Gd, Dy, and Y) samples by conventional solid‐state reaction and all the samples have shown monoclinic structure with P21/n space group. With the decrease in rare‐earth ionic size (<rR>), the <Ni–O–Mn> bond angle decreases, correspondingly a decrease in ferromagnetic (FM) Curie temperature is noticed. In the dielectric measurement, the dielectric anomaly shifts to high temperature with the decrease in the <rR> and shows no correlation with the FM Curie temperature and hints the absence of apparent magnetodielectric (MD) coupling. Appearance of multiple relaxations in the dielectric study suggests the electrical heterogeneity of the system. The dielectric/impedance analysis has revealed a close correlation between dc conductivity and the dielectrics; in fact, both dc resistivity and the grain relaxations follow the variable range hopping mechanism. The thermal activation of charge carriers at the grain boundary led to Maxwell–Wagner interfacial polarization. Finally, dielectric study under magnetic field showed no effect, it implies that not only the intrinsic MD is absent, but also the extrinsic MD due to the lack of magnetoresistance. 相似文献