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Cairo, Egypt

Abd El-Rheemkh M.,Dokki | Zaki S.S.,National Research Center of Egypt
International Journal of ChemTech Research | Year: 2015

A field experiment was carried out at El-Tina Plain in Ismailia Governorate during summer season of 2014, to study the effect of different levels of soil salinity on the growth and yield and content of nitrogen, phosphorus and potassium and its relationship with nutrient balance of peanut plants. Soil salinity levels were 6.3, 7.6, 8.8,9.4,10.6 and 11.8dS m-1. All agricultural operations were similarly in all the different areas of salinity. Plant samples were taken and the values of crop in six different areas in soil salinity. Diagnosis and Recommendation Integrated system was used to determined nutritional balance. The results indicated that increasing soil salinity decreasing straw and grain yield by 47.7 and 53.6% respectively. While grain content of oil and protein decreased by 7.84 and 12.1% respectively. Nutrient indices showed that increasing soil salinity decreased N and P in peanut plants, while potassium was not affected. So it must be interest to N and P fertilization under saline soil conditions. © 2015, Sphinx Knowledge House. All rights reserved. Source

Marzouk M.A.,Dokki | Elbatal F.H.,Dokki | Abdelghany A.M.,National Research Center of Egypt
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2013

The effects of gamma irradiation on spectral properties of Cr 2O3-doped phosphate glasses of three varieties, namely sodium metaphosphate, lead metaphosphate and zinc metaphosphate have been investigated. Optical spectra of the undoped samples reveal strong UV absorption bands which are attributed to the presence of trace iron impurities in both the sodium and zinc phosphate glasses while the lead phosphate glass exhibits broad UV near visible bands due to combined absorption of both trace iron impurities and divalent lead ions. The effect of chromium oxide content has been investigated. The three different Cr2O3-doped phosphate glasses reveal spectral visible bands varying in their position and intensity and splitting due to the different field strengths of the Na+, Pb2+, Zn2+cations, together with the way they are housed in the network and their effects on the polarisability of neighboring oxygens ligands. The effects of gamma irradiation on the optical spectral properties of the various glasses have been compared. The different effects for lead and zinc phosphate are related to the ability of Pb2+,and Zn2+to form additional structural units causing stability of the network towards gamma irradiation. Also, the introduction of the transition metal chromium ions reveals some shielding behavior towards irradiation. Infrared absorption spectra of the three different base phosphate glasses show characteristic vibrations due to various phosphate groups depending on the type of glass and Cr2O3 is observed to slightly affect the IR spectra. Gamma irradiation causes minor variations in some of the intensities of the IR spectra but the main characteristic bands due to phosphate groups remain in their number and position. © 2013 Elsevier B.V. All rights reserved. Source

Taha F.S.,Dokki | Mohamed G.F.,Dokki | Mohamed S.H.,National Research Center of Egypt | Mohamed S.S.,Dokki | Kamil M.M.,Dokki
American Journal of Food Technology | Year: 2011

Sunflower seed defatted meal (SM) is an underutilized source of protein due to the presence of chlorogenic acid (CGA) which imparts a greenish color to sunflower meal protein products. The aim of the present study was to prepare a (CGA) extract from SM and evaluate its biological activity. The study included extraction of phenolic compounds from SM, using 80% methanol, 80% ethanol and 80% acetone. The methods of extraction used included conventional extraction (CE), microwave assisted extraction (MAE) and ultrasound assisted extraction (UAE). Results proved that acetone achieved highest phenolic extraction, acetone-CE, acetone-MAE and acetone-UAE extracted 1802.76, 3668.81 and 3093.31 mg total phenolics/100 g meal. For safe nutritional reasons ethanol was chosen to continue the investigation. Ethanol concentrations 80, 70, 60, 50% were examined and results indicated 60% to be the most efficient. Using solvent mixtures with MAE-3 min and UAE-30 min proved effective. All phenolic extracts had a good antioxidant activity ranging between 86-95% as measured by free radical scavenging activity and between 74-93% as measured by the P-carotene bleaching method. Some of the above extracts were chosen for further investigation. The 60% ethanol-MAE-3 min and 60% ethanol-UAE-30 min extracts were effective for delaying oxidation of flaxseed oil. UV Spectroscopic analysis and HPLC analysis indicated that the chosen extracts contained between 687.22-1243.51 mg CGA/100 g as measured by UV-spectrophotometry and between 726.27-923.45 mg CGA/100 g as determined by HPLC. All chosen extracts showed potential as antimicrobial and anticarcinogenic agents. In conclusion the CGA extract was successfully prepared and proved to have antioxidant, antimicrobial and anticarcinogenic properties. © 2011 Academic Journals Inc. Source

Abd El-Salam A.M.E.,Dokki | Nemat A.M.,National Research Center of Egypt | Magdy A.,National Research Center of Egypt
Archives of Phytopathology and Plant Protection | Year: 2011

The biological activities of two species of bacteria isolated from soil of cotton fields identified as Bacillus subtilis strain NRC313 (BS NRC313) and Bacillus thuringiensis strain NRC335 (BT NRC335) were evaluated against the third larval instar of the cotton leafworm, Spodoptera littoralis (Boisd.). The different entomopathogenic bacteria of BS NRC313and BT NRC335 contained 10 × 108 cell/ml, and caused mortality of 100 and 97.3% for the above mentioned strains, respectively. Concentrations of 2.5 × 108 to 10 × 108 cell/ml of strains BS NRC313 and BT NRC335 were applied to the larvae: LC50 were 3.3 × 108 and 3.9 × 108 cell/ml respectively. The influence of exposure to toxin concentrations manifested in terms of decreasing the adult emergence and prolongation of the generation period. The percentage of larvae that survived and succeeded to pupate increased by decreasing the concentration. The longevity of adult emergence that resulted from larvae treated with Bacillus subtilis were 6.0±0.51 and 9.0±0.63 days at 5 × 108 and 2.5 × 108 cell/ml, respectively compared with 9.8±0.47 in control. The results indicated that Bacillus subtilis was more potent than Bacillus thuringiensis. Field applications of B. thuringiensis, B. subtilis and Reldan achieved 55.6, 67.4 and 89.4% reduction of the cotton leafworm larvae Spodoptera littoralis in clover plants under field conditions. © 2011 Taylor & Francis. Source

Abdel-Shafy H.I.,Dokki | Mansour M.S.M.,Egyptian Petroleum Research Institute
AWWA/AMTA 2014 Membrane Technology Conference and Exposition | Year: 2014

The aim of the present study is to investigate the efficiency of the membrane bioreactor (MBR) for the elimination of Pharmaceutical Active Compounds (PhAC's). For this purpose, natural separated urine was artificially contaminated with selected pharmaceuticals at 20 mg/l each. The pharmaceuticals are Levofloxacine, Ibuprofen and Atorvastatin. Microfiltration MBR pilot scale was examined for the removal of this artificially contaminated urine. The necessary transmembrane pressure difference is applied by the water head above the membrane (gravity flow) since a high value of this parameter is considered as crucial for the removal of these micropollutants. Pharmaceuticals were, in general, removed to a greater extent by the MBR integrated system. Few macro-parameters were determined for the studied natural human urine samples. It was observed that when the urine was artificially contaminated with pharmaceutical active (in combination), the level of COD increased. The average pH of the contaminated urine was 6.22. The averages values of the natural human urine was 6755, 2026, 547, 4.2, 13786, 14660 and 5725 mg/l for COD, BOD, total phosphates, nitrates, K, Na and Ca successively. The MBR process give high removal efficiency when applied on the artificial contaminated urine sample where 85%, 98% and 91% removal efficiency for Levofloxacine, Ibuprofen and Atorvastatin respectively. Concentration of the final effluent was 3, 0.4 and 1.8 mg/l for Levofloxacine, Ibuprofen and Atorvastatin successively. It was concluded that the PhAC's can be safely removed from urine that can be used as fertilizers without any environmental hazard. Copyright © 2014 by the American Water Works Association. Source

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