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1.
Amro A. El-Baz M. Kamal T. Ewida M. Abbas Shouman Mahmoud M. El-Halwagi 《Clean Technologies and Environmental Policy》2005,7(2):78-86
The objective of this paper is to develop a systematic methodology for mass integration in drain systems and watersheds. Mass integration is a holistic approach to the tracking, transformation, and allocation of species and streams. The watershed and drain system is first discretized into reaches. The MFA model developed in part I of this work (Simulation and Application to Ammonium Management in Bahr El-Baqar Drain System) is used to describe the environmental phenomena that affect the fate and transport of targeted species and the operators that characterize the system inputs and outputs as they relate to the surroundings. Next, we develop an integration framework which encompasses sources, sinks, and interception technologies to aid in the development for nitrogen-management strategies. The simulation model was transformed into a synthesis model by introducing optimization variables and including models for the potential management strategies. The problem of minimizing negative environmental impact subject to technical, social, economic, and regulatory constraints was posed as a nonlinear optimization program whose solution identified and synthesized the most effective solution strategies. These mathematical models and management strategies were coded into a computer-aided tool using LINGO programming platform. The program can be readily modified to address a variety of cases. Tradeoffs and sensitivity analysis were established using the devised model. The devised framework was applied to an Egyptian drain system (Bahr El-Baqar) along with the outfall to Lake Manzala. The results of the case study provide solution strategies for nitrogen management along with their technical, economic, and environmental implications. 相似文献
2.
Tolaymat Thabet Abdelraheem Wael El Badawy Amro Dionysiou Dionysios Genaidy Ash 《Clean Technologies and Environmental Policy》2016,18(7):2279-2291
Clean Technologies and Environmental Policy - Economic value is no longer adequate by itself as a proxy for the value-added benefits (VAB) assumed to be generated by emerging technologies such as... 相似文献
3.
Ahmed I. A. Abd El-Mageed Ahmed Esmail Shalan Lamiaa A. Mohamed Hisham A. Essawy Fouad Taha Amro K. F. Dyab 《Polymer Engineering and Science》2021,61(1):234-244
Styrene as a monomer was emulsified in water using several magnetite nanoparticles concentration and pH values. Emulsified styrene drops were used as templates for polymerization, in presence of water soluble free radical initiator, and formation of composite particles. Styrene template drops stabilization was verified by light as well as scanning electron microscopy imaging, which ensured the participation of the particles in building up a mechanical barrier to stop oil drops coalescence. Furthermore, the produced polystyrene composites were strongly attracted to an external magnet. The difference in particles size as a function of pH was elucidated using zeta potential measurements, which indicated dominance of pH on the hydrophilicity of the particles and consequently the extent of emulsification, which in turn affected the size of the obtained microspheres. Under some circumstances, capsules were formed instead of particles. Thereby, it can be concluded that the magnetic microspheres are optimally formed at pH 2.3 independently of the magnetite content used. 相似文献
4.
Ultra-high molecular weight polyethylene (UHMWPE)/ graphene nanoplatelets (GNPs) nanocomposite coatings were developed to reduce friction and wear in the absence of liquid lubrication. UHMWPE nanocomposite powders with different loadings (0.25, 1, and 2 wt.%) of GNPs were prepared and electrostatic spraying technique was then used to deposit the nanocomposite powders on aluminum alloy to form a thin coating. Friction and wear tests were conducted on the coatings against a flat-end pin, made of hardened tool steel to determine the best loading of GNPs. That was further tested to investigate the effect of sliding speed and contact pressure on its tribological properties and to establish coating operating limits. Results showed that UHMWPE nanocomposite coating reinforced with 1 wt.% GNPs showed the best tribological performance. It reduced wear rate by about 51% as compared to the pristine UHMWPE coating. The coating sustained a maximum sliding speed of 1 m/s at a contact pressure of 4 MPa equivalent to a pressure and velocity (PV) value of 4 MPa.m/s. 相似文献
5.
During oil production from several wells in Arabian Gulf area, significant productivity decline was noticed. One of the reasons behind the productivity decline might be asphaltene precipitation. Production data of the particular wells were collected and analyzed. It was found that many of these wells were injected with scale and corrosion inhibitors in downhole and surface equipment. Thus, it was desired to investigate the potential of formation damage due to asphaltene in the presence of scale and corrosion inhibitors as field chemicals. The effect of asphaltenes on the wettability, surface, and interfacial tensions were measured in the presence of scale and corrosion inhibitors. It was observed that the scale inhibitor did not indicate any alteration of the wettability, while the presence of corrosion inhibitor indicates high potential for wettability change into oil-wet conditions especially in the presence of asphaltenic oil. Similar results were obtained from the measurements of surface and interfacial tensions, in which corrosion inhibitors showed a significant decrease in surface and interfacial tensions. To assess the potential of asphaltene precipitation in the presence of both inhibitors and to study the effect of asphaltenes on the oil productivity, flooding experiments were carried out and oil/water relative permeability was determined.The results of flooding displacements showed that the presence of scale inhibitors indicates no effect on the oil/water relative permeability even in the presence of asphaltenes, while a significant decrease in oil relative permeability associated with an increase of residual oil saturation was observed in the presence of corrosion inhibitors.Mixture of scale and corrosion inhibitors showed no effect on relative permeability curves. 相似文献
6.
Islam Amro Raed Abu Zitar Hussein Bahadili 《International Journal of Speech Technology》2011,14(2):65-76
In this paper, a replacement algorithm for Linear Prediction Coefficients (LPC) along with Hamming Correction Code based Compressor
(HCDC) algorithms are investigated for speech compression. We started with an CELP system with order 12 and with Discrete
Cosine Transform (DCT) based residual excitation. Forty coefficients with transmission rate of 5.14 kbps were first used.
For each frame of the testing signals we applied a multistage HCDC, we tested the compression performance for parities from 2
to 7, we were able to achieve compression only at parity 4. This rate reduction was made with no compromise in the original
CELP signal quality since compression is lossless. The compression approach is based on constructing dynamic reflection coefficients
codebook, this codebook is constructed and used simultaneously using a certain store/retrieve threshold. The initial linear
prediction codec we used is excited by a discrete cosine transform (DCT) residual, the results were tested using the MOS and
SSNR, we had acceptable ranges for the MOS (average 3.6), and small variations of the SSNR (±5 db). 相似文献
7.
Hagir B. ElMaki Samia M. AbdelRahamanWisal H. Idris Amro B. HassanElfadil E. Babiker Abdullahi H. El Tinay 《Food chemistry》2007,100(1):362-368
White bean seeds were subjected to soaking in distilled water for 1, 2 and 3 days. In order to perform complete processing, the seeds were cooked until soft. Effects of soaking and/or cooking of white bean seeds on antinutritional factors, mineral contents and HCl-extractability were studied. Phytic acid and polyphenol contents of all cultivars were reduced. Soaking alone and soaking, followed by cooking, reduced mineral contents of the cultivars, but HCl-extractability was significantly (P ? 0.01) improved to varying extents, depending on cultivar type. Soaking and/or cooking treatment was thus found to be an effective technique and caused further improvement in the availability of both major and trace minerals in white bean. 相似文献
8.
Millet protein was solubilized by chymotrypsin; the soluble protein was conjugated to galactomannan under controlled conditions (60 °C, 76% RH) or polymerised by transglutaminase (TGase). SDS–PAGE patterns showed that the conjugated and polymerised proteins had higher molecular mass bands above the stacking gel. SDS–PAGE patterns also indicated that the digest was conjugated to galactomannan and polymerised by TGase. The free amino groups (OD340) of the conjugated and polymerised digest were greatly reduced. Although the chymotrypsin digest was considerably insoluble between pH 2.0 and 5.0, galactomannan conjugate was completely soluble at all levels of pH. TGase polymer was slightly insoluble at pH 4.0. Galactomannan conjugate resisted heat-induced aggregation, even after heating at 90 °C for 20 min, while TGase polymer resisted heat-induced aggregation up to 70 °C, after which its solubility started to decline. The emulsifying properties of the conjugate and the polymerized proteins were greatly improved, compared to the native and chymotrypsin digests. 相似文献
9.
El-Baz Amro A. Ewida M. Kamal T. Shouman M. Abbas El-Halwagi Mahmoud M. 《Clean Technologies and Environmental Policy》2004,7(1):51-61
This paper is aimed at developing a systematic and generally applicable methodology for material flow analysis in drainage systems and watersheds. In particular, this research has focused on developing a mathematical framework and application for the management of nitrogenous species (primarily ammonium ions). Nitrogen compounds are among the most important species contributing to ecological cycles. Indeed, the environmental and biological aspects of water systems and their surrounding systems are highly impacted by nitrogen compounds as they contribute to the quality, nutrition, and toxicity of these systems. A material flow model was developed to deal primarily with the water phase while including pertinent information on the solid and air phases as they interface with the water medium. Both spatial and discrete temporal dimensions were included to account for nitrogen flow and transformation. The model includes the various environmental phenomena that influence the fate and transport of targeted species (e.g., volatilization, precipitation, sedimentation, uptake by biota, adsorption, chemical and biochemical reactions, etc.). Furthermore, the model includes material flow analysis operators (or transfer functions) that characterize the system inputs and outputs as they relate to the surroundings. The aforementioned material flow analysis tools were combined in a computer-aided modeling platform to provide a complete material flow analysis and yield useful insights on the transport and fate of targeted species. The simulation results shed light on the system performance. Actual data for an Egyptian drainage system (Bahr El-Baqar) along with the outfall to Lake Manzala were used to illustrate the usefulness and applicability of the developed model. Comparison with the measured data confirmed the validity and fidelity of the model. 相似文献
10.
Costanza J El Badawy AM Tolaymat TM 《Environmental science & technology》2011,45(17):7591-2; author reply 7593-5