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101.
Amina A. Aly Rabab W. Maraei Hoda G. M. Ali 《Journal of the American Oil Chemists' Society》2016,93(3):397-404
Moringa oleifera is grown all over the world as a crop for its nutritious pods, leaves and seeds. The purpose of the present study was to evaluate the oil percentage, density, iodine value, saponification value, acid value and fatty acid profile of Egyptian moringa Seed oils. Moringa seeds were irradiated using 60Co at dose levels of 0.0 (control), 5, 10 and 15 kGy and oil was extracted from unirradiated and irradiated samples. Results showed that the oil percentage and density were almost unaffected. Irradiation reduced the iodine value, whereas the acid and saponification values were increased in all irradiated samples. The oil was found to contain high levels of unsaturated fatty acids, especially an omega‐9‐fatty acid (oleic) (up to 76.29 %) at a dose level of 15 kGy. Also at the same dose level, the dominant saturated acids were palmitic, stearic acid and arachidic (the three up to 12.66 %). GC–MS revealed the presence of different compounds (more than 50) in the moringa oil extract, among them alkaloids, terpenoids steroids, saturated and unsaturated fatty acids, aromatic and aliphatic hydrocarbons and polyphenolic compounds. Phenolic and falvonoid were significantly increased by increasing irradiation dose levels. Also, the antioxidant activity of irradiated seed oil increased by increasing the phenolic and flavonoid contents. Moringa oleifera could be grown by wide scale production as a potentially valuable crop. However, isolation of individual compounds and their biological activities needs to be covered in future to enhance its pharmacological importance and to open new avenues of research. 相似文献
102.
Exploring bioaugmentation strategies for azo dye CI Reactive Violet 5 decolourization using bacterial mixture: dye response surface methodology
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Lamia Ayed Karima Bekir Sami Achour Abdelkrim Cheref Amina Bakhrouf 《Water and Environment Journal》2017,31(1):80-89
The use of response surface methodology based on statistical design of experiments is becoming increasingly widespread in several sciences such as analytical and environmental chemistry. In the present study, the decolourization and the degradation efficiency of CI Reactive Violet 5 (CIRV5) was studied using a novel bacterial consortium. CIRV5 (1000 p.p.m.) biodegradation was investigated under shaking condition in mineral salt medium solution (MSM) at a 7.5 pH and a 25°C temperature. The degradation pathways were also predicted, using UV‐visible spectroscopy analysis. Under optimal conditions, the bacterial consortium was able to decolourize the dye completely (>99%) within 8 h. The colour and chemical oxygen demand (COD) removal were 99.29 and 94.93%, respectively. Polymerase chain reaction (PCR) technique was utilized to detect the adhesin genes ‘icaA’ and ‘icaD.’ Our results showed that Staphylococcus aureus had a high decolourization capacity. Phytotoxicity study using Triticum turgidum ssp durum showed the no toxicity of the produced products. 相似文献
103.
In the present study it is shown that jet flows from innovative rectangular air diffusion grilles with lobed ailerons ensure higher mixing in a room than baseline jets from classical rectangular air diffusion grilles with straight ailerons. The experimental approach uses time resolved and classical large scale PIV measurements. 相似文献
104.
Summary
Static and dynamic light scattering data from polystyrene in cyclohexane and toluene mixed solvent are reported. It is found
from the Zimm plot analysis of the static data that if the subtraction of solvent signal is made properly then, the results
are consistent with those in toluene indicating a preferential adsorption of the good solvent. Contin analysis of the dynamic
data yields two modes unlike the dynamics of polystyrene in single solvent solutions which exhibit a single mode at all polymer
concentrations covered here. A possible interpretation of the fast and slow modes is given.
Keywords: Mixed Solvent; Dilute Polymer Solution; Preferential Adsorption; Static and Dynamic Light Scattering; Relaxation Modes.
Received: 28 May 1999/Accepted: 8 September 1999 相似文献
105.
Teresa Lavecchia Giuseppina Rea Amina Antonacci Maria T. Giardi 《Critical reviews in food science and nutrition》2013,53(2):198-213
In recent years, both food quality and its effect on human health have become a fundamental issue all over the world. As a consequence of this new and increased awareness, American, European, and Asian policymakers have strongly encouraged the research programs on food quality and safety thematic. Attempts to improve human health and to satisfy people's desire for healthcare without intake of pharmaceuticals, has led the food industry to focus attention on functional or nutraceutical food. For a long time, compounds with nutraceutical activity have been produced chemically, but the new demands for a sustainable life have gradually led the food industry to move towards natural compounds, mainly those derived from plants. Many phytochemicals are known to promote good health, but, sometimes, undesirable effects are also reported. Furthermore, several products present on the market show few benefits and sometimes even the reverse - unhealthy effects; the evidence of efficacy is often unconvincing and epidemiological studies are necessary to prove the truth of their claims. Therefore, there is a need for reliable analytical control systems to measure the bioactivity, content, and quality of these additives in the complex food matrix. This review describes the most widespread nutraceutics and an analytical control of the same using recently developed biosensors which are promising candidates for routine control of functional foods. 相似文献
106.
Dr. Amina J. Yusuf Dr. Godwin A. Aleku Usman Rabiu Bello Dahiru Umar Liman 《ChemMedChem》2021,16(24):3635-3648
Snakebite envenomation (SBE) is an important public health issue that is now receiving renewed attention following its reclassification as a Neglected Tropical Disease (NTD). Most incidences occur in rural areas of resource-limited countries, as such, timely and appropriate medical care for SBE is often inaccessible. The administration of anti-snake venom serum (ASV) is the only effective definitive treatment of SBE, but treatment failure to available ASVs is not uncommon. Emerging evidence highlights the potential of small-molecule compounds as inhibitors against toxins of snake venom. This presents an encouraging prospect to develop an alternative therapeutic option for the treatment SBE, that may be amenable for use at the point of care in resource-constraint settings. In view of the pivotal role of natural products in modern drug discovery programmes, there is considerable interest in ethno-pharmacological mining of medicinal plants and plant-derived medicinal compounds toward developing novel snake venom-neutralising therapeutics. In this review, we compile a collection of medicinal plants used in the treatment of SBE in West Africa and highlight their promise as potential botanical drugs or as sources of novel small-molecule compounds for the treatment of SBE. The challenges that must be surmounted to bring this to fruition including the need for (sub) regional collaboration have been discussed. 相似文献
107.
Ghoumid Kamal Ghadban Amina Boukricha Sokaina Ar-reyouchi El Miloud Yahiaoui Reda Mekaoui Slimane Raschetti Marina Lepers Catherine 《Telecommunication Systems》2020,73(3):433-441
Telecommunication Systems - Optical code division multiple access (OCDMA) systems are attracting an increasing interest in optical fiber communication. This is due to the various advantages that... 相似文献
108.
Amina Meslem Ilinca Nastase Kamel Abed-Meraim 《Journal of Engineering Physics and Thermophysics》2008,81(1):106-111
An experimental investigation of flow in a turbulent isothermal air lobed jet is presented. A lobed jet is compared, in the
near field, with an isothermal axisymmetric jet with the same exit Reynolds number in terms of dynamics and mixing enhancement.
It was found that the streamwise variation of the volumetric flow rate is characterized by a slope is more than twice larger
than that for the reference circular jet. This high entrainment rate is governed, at the same time, by the turbulent structures
generated by the asymmetric shape of the nozzle and by the high convection in these structures induced by the inner and outer
penetration angles of their lobes.
Published in Inzhenerno-Fizicheskii Zhurnal, Vol. 81, No. 1, pp. 102–107, February–March, 2008. 相似文献
109.
A modeling technique of a subway network is performed in order to quantify the effect of insulated negative current rail on resonance frequencies. A DC track circuit is modeled by means of transmission line modeling (TLM) approach to perform line current and voltage calculation. Impedance and admittance required by TLM equations are first derived. System impedance is expressed in terms of internal and external impedance. The former is calculated using exact expression of a cylindrical conductor whereas the external impedance is taken as the sum of conductor's reactance considering a perfect conducting plane and the ground impedance. The well-known Carson's formulas for ground impedance are compared to Sunde's one to investigate frequency range applicability of the former. Simulations reveal that Carson's expressions are valid for frequencies up to 50 kHz. It appears, however, that using Cason's formulas for higher frequencies lead to underrating ground impedance. To investigate the accuracy impact of internal impedance, ground impedance and inductance on resonance frequencies, a sensitivity analysis is performed. A noticeable resonance effect is observed at 8 kHz for a 10 km length rail. Simulation results show the network impedance effect on track current and voltage. 相似文献
110.
Abderrahim Hammoud Brahim Meftah Mohammed Azzoune Lila Radji Boumazza Zouhire Mataoui Amina 《Journal of Nuclear Science and Technology》2013,50(9):1154-1160
Nuclear safety analysis remains of crucial importance for both the design and the operation of nuclear reactors. Safety analysis usually entails the simulation of several selected postulated accidents, which can be divided into two main categories, namely reactivity insertion accident (RIA) and loss of flow accident (LOFA). In this paper, thermal-hydraulic simulations of fast LOFA accident were carried out on the new core configuration of the material test research reactor NUR. For this purpose, the nuclear reactor analysis PARET code was used to determine the reactor performance by calculating the reactor power, the reactivity and the temperatures of different components (fuel, clad and coolant) as a function of time. It was observed that during the transient the maximum clad temperature remained well below the critical temperature limit of 110 °C, and the maximum coolant temperature did not exceed the onset of nucleate boiling point of 120 °C. It is concluded that the reactor can be operated at full power level with sufficient safety margins with regard to such kind of transients. 相似文献