In wide range of chemical, petrochemical and energy processes, it is not possible to manage without slurry bubble column reactors. In this investigation, time average local gas holdup was recorded for three different height to diameter (H/D) ratios 3, 4 and 5 in 18" diameter slurry bubble column. Air-water-glass beads system was used with superficial velocity up to 0.24 m/s. the gas holdup was measured using 4-tips optical fiber probe technique. The results show that the axial gas holdup increases almost linearly with the superficial gas velocity in 0.08 m/s and levels off with a further increase of velocity. A comparison of the present data with those reported for other slurry bubble column having diameters larger than 18" and H/D higher than 5 indicated that there is little effect of diameter on gas holdup. Also, local section-average gas holdups increase with increasing superficial gas velocity, while the effect of solid loading are less significant than that of superficial gas velocity.
Corrosion Resistance Enhancement for low carbon steel is very important to extend its life service, the coating process is one of the methods which can using to achieve this, and it's the most important in surface treatments to improve the properties of metals and alloys surfaces such as corrosion resistance. In this work, low carbon steel was nitrided and coated with nano zinc using gas phase coating technical, to enhance the resistance of corrosion. The process included adding two layers. The first, a nitride layer, was added by precipitating nitrogen (N) gas, and the second, a zinc (Zn) layer, was added by precipitating Zn. The process of precipitating was carried out at different periods (5, 10, and 15 minutes). Scan electron mi
... Show MoreThe article examines metaphors as one of the fundamental means used by D. Rubina when writing the novel “Parsley Syndrome” to form images of dolls as equal heroes of the work. The author of the article continues research related to the work of Dina Ilinichna Rubina, a representative of modern Russian prose.
The acoustic efforts of the glass were found in the meanings mixed with other linguistic, grammatical and morphological issues, as the glass was not allocated to the detective or separate chapters in the meanings. The glass-walled in the audio lesson according to the doctrine of the optical, has stated so in several places of its meaning. Glass is interested in mentioning the strong qualities that have a great impact in the chorus and replacements such as loudness, dishes, arrogance, whistling, repetition, and richness. Glass was concerned with the phenomenon of diphtheria great care, and explained its purpose of seeking lightness and ease of pronunciation, and Siboe agreed in its origins and issues, and the glass used three criteria in
... Show MoreIn this research prepare membranes pure silicon carbide (SiC) as well as gas Alloy (ammonia) and using a laser was leaked membrane of glass flooring. To Drasesh optical properties of membranes prepared depending on the technique (Swanepoel) and Adhrt results obtained in general increased permeability pure silicon membranes
Films of CdSe have been prepared by evaporation technique with thickness 1µm. Doping with Cu was achieved using annealing under argon atmosphere . The Structure properties of these films are investigated by X-ray diffraction analysis. The effect of Cu doping on the orientation , relative intensity, grain size and the lattice constant has been studied. The pure CdSe films have been found consist of amorphous structure with very small peak at (002) plane. The films were polycrystalline for doped CdSe with (1&2wt%) Cu contents and with lattice constant (a=3.741,c=7.096)A°, and it has better crystallinty as the Cu contents increased to (3&5wt%) Cu. The reflections from [(002), (102). (110), (112), and (201)]planes are more prominen
... Show MoreWe report here the observation of 16 µm superradiance laser action generated from optical pumping of CF4 gas molecules (which is cooled to 140 Kº by a boil-off liquid-N2) by a TEA-CO2 laser 9R12 line. Output laser pulses of 7 mJ and 200 ns have been obtained.
Electrochemical method was used to prepare carbon quantum dots (CQDs). Size of matter was nature when evaluate via X-ray diffraction (XRD). A distinct peak at 2θ equal to 31.6° and three other small peaks at 38.28°, 56.41° and 66.12° were observed. The measures of Fourier Transform Infrared Spectroscopy (FTIR) showed the bonds in the transmittance spectrum are manufactured with carbon nanostructures in view. The first peaks are the O–H stretching vibration bands at (3417 and 2922) cm−1, (C–O–H at 1400, and 1317) cm−1, (C–H), (C=C), (C–O–H), (C=O), and (C–O) bonds at 2850, 1668, 1101, and 1026 cm−1 sequentially. The transmission electron microscopy (TEM) results presented that the spherical CQDs are in shape and on a
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Through this study, I tried to identify the grammatical efforts of one of the most important authors of the footnotes that were built on the luminous benefits marked with (Explanation of Mulla Jami in Grammar), and he is Sheikh Isamah Allah Al-Bukhari, who died in the eleventh century AH, trying as much as possible to stay away from the path of tradition in repeating the efforts of Those who preceded me in explaining the grammatical efforts of many grammarians, and perhaps what helped me in this is the characteristics that characterize the notes owners that may distinguish them from other owners of grammatical authorship, as a result of what characterized the personality of the notes owners from the predominance of the in
... Show MoreBased on the theoretical ideas of E. Cassirer, a methodology is developed and an analysis of the painting work by J. Saleem, a representative of modern Iraqi painting, is carried out. While comparing the artistic programme of J. Saleem and the views of E. Cassirer, the methodological potential of the theory of the symbol for the art criticism analysis of the regional painting is clarified. Comparative analysis with the inclusion of the works of B. Buffet, B. Turetsky, J. Miro helps to see the multiple meanings of the same cultural symbol in thematically similar works of different years, created in different socio-cultural circumstances. The article shows that for regions with a shorter history (France, Russia, Spain, etc.), which have lo
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