Response Spectrum Analysis of Suspension Bridges for Random Ground Motion

The response spectrum method of analysis for suspension bridges subjected to multicomponent, partially correlated stationary ground motion is presented. The analysis is based on the relationship between the power spectral density function and the response spectrum of the input ground motion and fundamentals of the frequency domain spectral analysis. The analysis duly takes into account the spatial correlation of ground motions between the supports, the quasi-static component of the response, and the modal correlation between different modes of vibration. A suspension bridge is analyzed under a set of important parametric variations in order to (1) compare between the responses obtained by the response spectrum method of analysis and the frequency domain spectral analysis; and (2) investigate the behavior of suspension bridges under seismic excitation. The parameters include the spatial correlation of ground motion, the angle of incidence of the earthquake, the ratio between the three components of ground motion, the number and nature of modes considered in the analysis, and the nature of the power spectral density function of ground motion. It is shown that the response spectrum method of analysis provides a fair estimate of responses under parametric variations considered in the study.     

A cost allocation approach for irrigation water in Upper Egypt

An approach for estimating irrigation water cost is presented and applied to Upper Egypt. Two cost models are used. The first model is to estimate the cost of irrigation water if controlled with a multi-purpose structure. The model is used in estimating the irrigation cost at the High Aswan Dam. The second model is to allocate the cost of irrigation structures and the cost of irrigation at the multi-purpose structures among the served areas. The two models are applied to estimate the cost of irrigation water at the different regions of Upper Egypt.     

Photoelectrochemical conversion of CO2 using nanostructured PbS–Si Photocathode

Journal of Applied Electrochemistry - A n-type nanostructured PbS thin films were prepared by chemical bath deposition onto flat Silicon (Si) and Silicon nanowires (SiNWs) which were derived from...     

UV-Protective Finishing of Cellulose/Wool Blended Fabrics

There is a growing need and special attention for using textile products to provide effective protection against such damage of UV-radiation, i.e., skin cancer, sun burn, and photo-aging, in the recent years. In this research work a new approach for upgrading the UV-protective properties of cotton/wool and viscose/wool blended fabrics for high quality/trans seasonal apparel, was investigated. Factors affecting the UVB-protection function of the aforementioned substrates such as type and concentration of finishing additives, as well as subsequent treatment with cu-acetate or dyeing with anionic or cationic dyes were studied. The experimental data show that: i) the enhancement in the UV-protection factor (UPF) of the finished fabrics is determined by the type of finishing additives, i.e., citric acid ≥ aspartic acid ≥ tartaric acid ≥ none, chitosan TEA.HCL ≥ choline chloride ≥ none, β-cyclodextrin CMC-30 PEG-600 > none, and Siligen® WW > W Siligen® PEP ≥ Leomin® NI-ET ≥ none, regardless of the used substrate, ii) UPF values are governed by the type of substrate, i.e., viscose/wool ≥ cotton/wool, irrespective of the used additives, iii) post-treatment with cu-acetate or post-dyeing with the used dyestuffs brings about a dramatic improvement in UPF values, and iv) UPF values are determined by the finishing regime and follow the descending order:

Resin finishing → post dyeing > resin finishing → posttreatment with Cu-acetate > resin finishing in presence of additives > resin finishing in absence of additives.     

An Efficient Tetrabutylammonium Fluoride (TBAF)‐Catalyzed Three‐Component Synthesis of 3‐Substituted Indole Derivatives under Solvent‐Free Conditions

An expedient and efficient one‐pot three‐component synthesis of 3‐substituted indoles has been developed by the reaction of indoles, active methylene compounds and aldehydes using a catalytic amount of tetrabutylammonium fluoride under solvent‐free conditions.     

Investigation of New Routes for the Synthesis of Mn4Si7

In this work, we investigated two different ways to synthesize the higher manganese silicide (HMS) Mn₄Si₇. In the first approach, a bulk material was subjected to a heating treatment at 773 K (500 °C) under high pressure (5 GPa) in a multianvil system, whereas in the second one, thin manganese layers deposited onto silicon substrate (Mn/Si) underwent a rapid thermal annealing at different temperatures under vacuum. The guiding principle of these investigations was to study HMS materials in a constrained environment. The atomic composition of the bulk system we studied was Mn₃₅Si₆₅. At room temperature and atmospheric pressure, the sample was made of two phases, namely Mn₂₇Si₄₇ and pure silicon, the latter one being in small quantity. X-ray diffraction measurements performed on this sample after high-temperature—high-pressure treatment evidenced a complete transformation of Mn₂₇Si₄₇ into Mn₄Si₇. Rapid thermal annealing performed on Mn/Si systems also led to the formation of Mn₄Si₇.     

Design,Construction and Characterization of AC Atmospheric Pressure Air Non-thermal Plasma Jet

This paper presents the design and construction of non-thermal plasma jet device which was built in plasma phys. Dept., NRC, AEA, Egypt with a plasma application group. This design will be useful to initiate research in different fields such as low temperature plasma, polymer and biomedical applications. The experimental operation of this device is conducted with power supply of (10 kV, 30 mA, and 20 kHz). The discharge process takes place by using Air as input gas with different flow rates. The experimental results showed that the maximum plasma jet length of 7 mm is detected at air flow rate of 12 L/min. The electrical characteristics of discharge at different flow rates of Air such as discharge voltage, current, mean power, power efficiency, and energy have been studied by using potential dividers and Lissajous figure techniques. The results of plasma jet temperature along the jet length showed that the jet plasma has approximately a room temperature at the end of jet column.     

Electrodeposition and characterization of NiMoW alloy as electrode material for hydrogen evolution in alkaline water electrolysis

The electrodeposition of ternary NiWMo alloys films from citrate ammonia-free electrolyte at room temperature was studied in an effort to evaluate the effect of applied potential on the composition limits, corrosion resistance and the electrocatalytic properties of the deposits towards the hydrogen evolution reaction (HER) in concentrated alkaline solution. The alloys were potentiostatically electrodeposited onto pure copper sheet substrates. The electrodeposits were characterized by means of field-emission scanning microscopy (FESEM) and energy dispersive X-ray analysis (EDXA). In an electrolyte where ${\text{MoO}}_4^{2?}/{\text{WO}}_4^{2?}=1:1$, at a given deposition potential, there is more Mo than W in the deposits, indicating an advantageous induced co-deposition of Mo compared to W. The nucleation mechanism, studied according to Scharifker-Hills theoretical model, revealed an instantaneous nucleation followed by a three-dimensional growth. On the hand, increasing ${\text{MoO}}_4^{2?}/{\text{WO}}_4^{2?}$ ratio in the electrolyte under the same deposition potential reduced both Ni and W content in the deposits. A different trend was observed in an equimolar solution, when applying more negative potentials, both Mo and W contents decreased leading to the enhancement of Ni amount. The stability in corrosive media and the catalytic performances of the coatings depended mainly on the applied overpotentials, A mechanism of induced co-deposition of molybdenum and tungsten with nickel is proposed and discussed.     

Effect of Ni3Nb precipitation on the corrosion resistance of Inconel alloy 625

Inconel is a registered trademark of the INCO family of companies.