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61.
Inconel is a registered trademark of the INCO family of companies. 相似文献
62.
63.
An EPRI project with the objective of developing an optimized 345 kV paper-polypropylene-paper pipe cable system is discussed. Highlights of the design and manufacture of the new reduced-wall cable are detailed. Pertinent aspects of a major corollary development, establishing a US domestic supplier of PPP, are described. Laboratory qualification tests suggest that reasonable cable optimization is achieved. An optimized PPP joint design is described. The economic advantages and versatility of this new cable system are summarized 相似文献
64.
The conflict between performance measured in terms of economic and income redistribution objectives, resilience and reliability of irrigated agricultural expansions in developing countries is investigated via a planning framework consisting of three sequential optimization models. The first model determines the most economic planning alternatives. The second model examines, in terms of an income redistribution criterion, the social attractiveness of each plan. The third model determines resilience and operating rules of the various alternatives. The planning framework is appled for a hypothetical agricultural expansion on the order of 30 000 hectares based on data from the Nile Delta in Egypt. The trade-off between system performance, reliability and resilience is derived. 相似文献
65.
Peel oils of lemon, grapefruit and navel orange were tested for insecticidal activities against larvae and adults of Culex pipiens and Musca domestica. Lemon peel oil was the most effective against larvae and adults of C. pipiens. Grapefruit peel oil was more toxic to adults of M. domestica while lemon oil, was more toxic Musca larvae. On the other hand, the orange peel oil was the least effective against larvae and adults of both species. The toxicity of oils applied to larval stages was extended to pupal and adult stages. C. pipiens adults appeared with paralyzed legs, while M domestica adults appeared normal. The weights of pupae treated as larvae were generally less than that of the control. All oils produced deleterious effects on fecundity of survivors of sublethal doses. The effect was obviously recorded in treated adults. Treatment of Culex & Musca with oils caused serious latent effect. 相似文献
66.
Allam M.E. Kinnick R.R. Greenleaf J.F. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1996,43(5):923-935
For pt. I see ibid., vol. 43, no. 5, p. 911-22 (1996). Pt. I presented the basic principles for applying high-resolution wide-band direction-of-arrival estimation techniques to pulsed-wave Doppler ultrasound. Such techniques provide high-resolution velocity profiles and enable the identification of multiple velocity components inside a sample volume. Another important application is the identification and rejection of wall clutter signals. A first and essential step in applying these techniques is to convert the wide-band echoes to narrow band. The 2D DFT projection method is used for this conversion. Two different narrow-band high-resolution methods are then applied to estimate the velocity distributions; the minimum variance (MV) and the multiple signal classification (MUSIC). Experimental results are presented to illustrate the potentials and limitations of applying wide-band DOA methods to different applications in pulsed-wave Doppler ultrasound 相似文献
67.
A new cerium oxide thermal barrier coating for superalloys has been investigated. The coating is applied by hot dipping superalloy substrates into a molten bath of low melting point Ce-Ni alloy. Annealing and selective oxidation of cerium at low oxygen activities produce a duplex coating of a continuous outer layer of cerium oxide (CeO2) and an inner composite CeO2-substrate layer.The effects of coating composition and processing variables on the microstructure and integrity of the coating on nickel- and cobalt-base alloys were studied in detail. Isothermal and cyclic oxidation tests showed that coating spallation could occur and was associated with the oxidation of nickel and cobalt incorporated in the coating. A model for the formation of the CeO2 barrier and the subscale region is proposed that explains the presence of unwanted nickel and cobalt. 相似文献
68.
H. S. Soliman F. M. Allam A. A. El-Shazly 《Journal of Materials Science: Materials in Electronics》1996,7(3):233-239
Seven Cd x Zn(1 ? x Te solid solutions with x = 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 and 1.0 were synthesized by fusing stoichiometric amounts of CdTe and ZnTe constituents in silica tubes. Each composition was used in the preparation of a group of thin films of different thicknesses. Structural investigation of the obtained films indicates they have a polycrystalline structure with predominant diffraction lines corresponding to (111) (220) and (311) reflecting planes, which can be attributed to the characteristics of growth with the (111) plane. The optical constants (the refractive index n, the absorption index k, and the absorption coefficient α) of Cd x Zn(1 \s -x) Te thin films were determined in the spectral range 500–2000 nm. At certain wavelengths it was found that the refractive index, n, increases with increasing molar fraction, x. It was also found that plots of α2 (hv) and α1/2 (hv) yield straight lines, corresponding to direct and indirect allowed transitions respectively obeying the following two equations: $$\begin{gathered} E_g^d = 1.583 + 0.277x + 0.197x^2 \hfill \\ E_g^{ind} = 1.281 + 0.111x + 0.302x^2 \hfill \\ \end{gathered}$$ 相似文献
69.
Fatma Allam Mohamed Elnouby Soraya A. Sabry K.M. El-Khatib Dalia E. El-Badan 《International Journal of Hydrogen Energy》2021,46(20):11419-11432
Microbial electrochemical cells (MXCs) have been developed as promising devices mainly for energy generation and wastewater treatment. Among the well-defined electroactive bacteria, Pseudomonas aeruginosa has been demonstrated for its electroactivity through mediated electron transfer in MXCs. In addition to phenazine pigments that mediate external electron transfer (EET), biofilm formation and rhamnolipid production are considered important factors affecting electricity generation by P. aeruginosa in MXCs. In the present study, a local electroactive strain of P. aeruginosa was isolated. Bacterial identification was done by Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), and 16S rDNA as P. aeruginosa FA17. Cyclic voltammetric studies showed the appearance of oxidation peaks which contributes to pyocyanin. Plackett-Burman designs were employed to optimize the composition of artificial wastewater (AWW) media for current generation (represented the mediated electron transfer), biofilm formation and rhamnolipid production by FA17. Ammonium chloride was the significant variable affecting electron transfer of FA17 for current generation in three-electrode set-up by using cyclic voltammetry analyses. While phosphate, Sodium dodecyl sulfate (SDS) and chlorides were the major factors influencing biofilm formation by FA17, phosphate, inoculum size, MgSO4.7H2O, pH, and SDS were the significant variables for rhamnolipid production. This study provides knowledge about the electrochemical behavior of mediated electron transfer catalyzed by P. aeruginosa FA17, biofilm formation, and rhamnolipid production in response to medium composition, which leads to the possibility for the future development of power produced by MXCs using the electroactive FA17. 相似文献
70.
Ayat N. El-Shazly Mahmoud A. Hamza Nageh K. Allam 《International Journal of Hydrogen Energy》2021,46(45):23214-23224
Herein, we report on the defect engineering of BiPO4 nanorods (NRs) via a facile room-temperature template-free co-precipitation method, followed by hydrogen treatment. The hydrogen treatment temperature determined the type of induced defects in the fabricated BiPO4 NRs and consequently their photocatalytic performance. Upon varying the annealing temperature, the x-ray diffraction (XRD) analysis showed phase transformation and x-ray photoelectron spectroscopy (XPS) analysis revealed variation in the oxygen vacancy content. At moderate treatment temperatures (200–300 °C), shallow defects were predominant, which extended the optical activity of the material to the visible region and increased the photocurrent 3 times when compared to that of bare BiPO4 NRs. However, treatment at higher temperatures completely altered the crystalline structure, destructed the morphology of the BiPO4 NRs, and severely affected the photoelectrochemical performance. 相似文献