The present research was conducted to reduce the sulfur content of Iraqi heavy naphtha by adsorption using different metals oxides over Y-Zeolite. The Y-Zeolite was synthesized by a sol-gel technique. The average size of zeolite was 92.39 nm, surface area 558 m2/g, and pore volume 0.231 cm3/g. The metals of nickel, zinc, and copper were dispersed by an impregnation method to prepare Ni/HY, Zn/HY, Cu/HY, and Ni + Zn /HY catalysts for desulfurization. The adsorptive desulfurization was carried out in a batch mode at different operating conditions such as mixing time (10,15,30,60, and 600 min) and catalyst dosage (0.2,0.4,0.6,0.8,1, and 1.2 g). The most of the sulfur compounds were removed at 10 min for all catalyst types. The maximum sulfur removal was 56% using (Ni+Zn)/HY catalyst at 1.2 g dose for 24 h. The adsorption kinetics and isotherm of sulfur removal were studied, and results indicated that desulfurization adsorption kinetic was 2nd order, and Temkin and Freundlich models were the best representation isotherm.
Desde la Salamanca de doradas piedras que tantas veces cantara, don Miguel de Unamuno dio a la literatura y al pensamiento españoles unas obras que, a pesar de muchos pesares, perdura viva, como viva fue su agónica existencia.
El bilbaíno Miguel de Unamuno (1864-1936) es autor de al menos, doce obras teatrales. Su costumbre de mezclar géneros literarios, sin distinguir claramente el drama de la novela dialogada, le llevó a preferir el teatro leído. De ahí que sus estrenos fuesen, frecuentemente, muy posteriores a las ediciones impresas.
Abstract:
The Bilbao Miguel de Unamuno (1864-1936) is the author of at least twelve plays. His habit of mixing genres,
... Show MoreEl presente trabajo es un estudio sintáctico y práctico en que se trata de explicar el funcionamiento de "ya" en la oración, el objetivo principal de este estudio es el análisis del complejo significado de "ya" teniendo en cuenta el modo de la acción del verbo sobre el que incide semánticamente el adverbio.
En este estudio empírico aclaramos los distintos valores de "ya" e intentamos demostrar que es un adverbio que significa una determinada modalidad del enunciado.
Pero antes de explicar detalladamente nuestro estudio presentaremos un resumen del adverbio en general , porque "ya" es uno de los adverbios de tiempo , este p
... Show MoreAll alive languages had passed linguistic changes that made the mother language not recognized by its present speakers. Some of these changes are: syntactical, semantical, orthographical, phonetical and lexical.During the period of changes which extends over centuries, there had been a lof of written texts, such as literately texts, biographies, personal memories and manuscripts which are conserved until now as a literatel, historic and linguistic testimonies.Spanish is one of these languages that had been changed, so, the poem of the Cid (1145) was written in a Spanish which differs from the Spanish in which Cervantes wrote the Don Quixote in (1605/1615) and the Spanish of both of them differs from the Spanish of Francisco Ayala and Azorin
... Show MoreIn this study, the stress-strength model R = P(Y < X < Z) is discussed as an important parts of reliability system by assuming that the random variables follow Invers Rayleigh Distribution. Some traditional estimation methods are used to estimate the parameters namely; Maximum Likelihood, Moment method, and Uniformly Minimum Variance Unbiased estimator and Shrinkage estimator using three types of shrinkage weight factors. As well as, Monte Carlo simulation are used to compare the estimation methods based on mean squared error criteria.
he effect of different cultural conditions on production of bioemulsifier from Serratia marcescens S10 was determined; different carbon and nitrogen sources were used such as: different oils include: edible (vegetable) oils (olive oil, sesame oil, sun flower oil and corn oil) and heavy oils (oil 150, oil 60, oil 40) as carbon sources and (NH4Cl, casein, (NH4)2SO4, peptone, tryptone, gelatin and yeast extract) as nitrogen sources were added to production media. Bioemulsifier was estimated by measuring the surface tension (S.T), emulsification activity (E.A) and emulsification index (E24%). The best results of bioemulsifier production from Serratia marcescens S10 were obtained at pH8 and incubated at 37ºC for 5days, using sesame oil
... Show MoreIn this paper we generalize Jacobsons results by proving that any integer in is a square-free integer), belong to . All units of are generated by the fundamental unit having the forms
our generalization build on using the conditions
This leads us to classify the real quadratic fields into the sets Jacobsons results shows that and Sliwa confirm that and are the only real quadratic fields in .
The cement slurry is a mixture of cement, water and additives which is established at the surface for injecting inside hole. The compressive strength is considered the most important properties of slurry for testing the slurry reliability and is the ability of slurry to resist deformation and formation fluids. Compressive strength is governed by the sort of raw materials that include additives, cement structure, and exposure circumstances. In this work, we use micro silica like pozzolanic materials. Silica fume is very fine noncrystalline substantial. Silica fume can be utilized like material for supplemental cementations for increasing the compressive strength and durability of cement. Silica fume has very fine particles size less
... Show MoreNonlinear diffraction patterns can be obtained by focusing a laser beam through a thin slice of the material. Here, we investigated experimentally the formation of the far field nonlinear diffraction patterns of cw laser beam at 532 nm passing through a quartz cuvette containing multi-wall carbon nanotubes (MWCNT's) suspended in acetone and in DI water at concentrations of 0.030.wt.%, 0.045 wt.%, 0.060 wt.%, and 0.075 wt.%. Our results show that increasing the concentration of both types of suspensions (MWCNTs in acetone and MWCNTs DI water) led to increase in the number of pattern rings which indicates an increase in their nonlinear refractive indices. Moreover, MWCNTs DI water suspension at a concentration of 0.075 wt. % was more effic
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