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Sonia Jam Masume Ghalbi Ahangary Ahmad Tavasoli Kambiz Sadaghiani Ali Nakhaei Pour 《Reaction Kinetics and Catalysis Letters》2006,89(1):71-79
Summary An integrated process for producing liquid fuels from synthesis gas via a two-stage Fischer-Tropsch (FT) reaction is disclosed. An iron catalyst was used in the first bed of a fixed-bed reactor
followed by a ruthenium promoted cobalt catalyst in the second bed. The activity and selectivity of the dual-bed system were
assessed and compared with those using catalysts in a single bed system, separately. The methane selectivity in the dual-bed
reactor was about 11% less compared to that of the single-bed system. The C5+ selectivity for the dual-bed reactor was 19.7% higher than that of the single-bed system. 相似文献
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Preparation and characterization of Cu (II) supported on poly(8‐hydroxyquinoline‐p‐styrene sulphonate) and its application as catalyst for the synthesis of hexahydroquinolines 下载免费PDF全文
Ardeshir Khazaei Mahsa Tavasoli Vahid Jamshidi Fatemeh Gohari Ghalil Ahmad Reza Moosavi‐Zare 《应用有机金属化学》2018,32(7)
Cu ( II ) supported on poly(8‐hydroxyquinoline‐p‐styrenesulfonate) (Cu ( II )@PHQSS) was prepared and fully characterized by the different techniques including fourier transform infrared spectroscopy (FT‐IR), 1H NMR, 13C NMR, thermal gravimetric analysis (TGA), differential thermal gravimetric (DTG), differential thermal analysis (DTA), scanning electron microscope (SEM) and energy dispersive X‐ray analysis (EDS). Afterward, the Cu ( II )@PHQSS as nanostructured catalyst was used as catalyst for the synthesis of hexahydroquinolines. 相似文献
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Let ${(R, \mathfrak{m})}$ be a commutative Noetherian local ring of Krull dimension d, and let C be a semidualizing R-module. In this paper, it is shown that if R is complete, then C is a dualizing module if and only if the top local cohomology module of ${R, H _{\mathfrak{m}} ^{d} (R)}$ , has finite G C -injective dimension. This generalizes a recent result due to Yoshizawa, where the ring is assumed to be complete Cohen-Macaulay. 相似文献
4.
Let R be a commutative Noetherian ring. It is shown that the finitely generated R-module M with finite Gorenstein dimension is reflexive if and only if M p is reflexive for p ∈ Spec(R) with depth(R p) ? 1, and $G - {\dim _{{R_p}}}$ (M p) ? depth(R p) ? 2 for p ∈ Spec(R) with depth(R p) ? 2. This gives a generalization of Serre and Samuel’s results on reflexive modules over a regular local ring and a generalization of a recent result due to Belshoff. In addition, for n ? 2 we give a characterization of n-Gorenstein rings via Gorenstein dimension of the dual of modules. Finally it is shown that every R-module has a k-torsionless cover provided R is a k-Gorenstein ring. 相似文献
5.
Reza Davarkhah Elmira Farahmand Asl Mohammad Samadfam Maryam Tavasoli Parisa Zaheri Mojtaba Shamsipur 《Chemical Papers》2018,72(6):1487-1497
2-Thenoyltrifluoroacetone has been offered as a mobile carrier in organic phase for the transport and selective separation of yttrium from aqueous media using a liquid membrane system. Perceivably, the use of n-propylamine (PA) in the source phase enhances the transport of yttrium ions. The extraction and stripping conditions have entirely been evaluated and explained. The suggested method has been utilized for the separation of yttrium(III) from its binary mixtures with strontium(II) and some other cations such as Ni2+, Co2+, Ag+, Fe2+, Al3+, Cu2+, Hg2+and Cs+ in aqueous solutions of pH 5.4 in the presence of PA, while 1 M nitric acid was acting as a stripping agent in the receiving division. Cyanide ion and 5-sulfosalicylic acid have been used as masking agents to minimize the interferences from different transition metal ions and Al3+ in the source phase, respectively. 90Y in secular equilibrium with 90Sr in the source phase, was transferred to receiving phase and separated completely from its long-lived parent isotope. The activity of the transported 90Y was found to decay with a half-life 64.17 ± 0.05 h. The purity of yttrium-90 was comparable or better than the other applied liquid membrane systems for purification of yttrium-90. 相似文献
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Ardeshir Khazaei Mahsa Tavasoli Ahmad Reza Moosavi-Zare 《Research on Chemical Intermediates》2018,44(10):5893-5910
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This note makes a correction to the paper “Top local cohomology modules and Gorenstein injectivity with respect to a semidualizing module”. 相似文献
10.
Ahmad Tavasoli Saba Karimi Somayeh Taghavi Zahra Zolfaghari Hamideh Amirfirouzkouhi 《天然气化学杂志》2012,(5):605-613
An extensive study of Fischer-Tropsch (FT) synthesis on cobalt nano particles supported on γ-alumina and carbon nanotubes (CNTs) catalysts is reported.20 wt% of cobalt is loaded on the supports by impregnation method.The deactivation of the two catalysts was studied at 220 C,2 MPa and 2.7 L/h feed flow rate using a fixed bed micro-reactor.The calcined fresh and used catalysts were characterized extensively and different sources of catalyst deactivation were identified.Formation of cobalt-support mixed oxides in the form of xCoO yAl2O3 and cobalt aluminates formation were the main sources of the Co/γ-Al2O3 catalyst deactivation.However sintering and cluster growth of cobalt nano particles are the main sources of the Co/CNTs catalyst deactivation.In the case of the Co/γ-Al2O3 catalyst,after 720 h on stream of continuous FT synthesis the average cobalt nano particles diameter increased from 15.9 to 18.4 nm,whereas,under the same reaction conditions the average cobalt nano particles diameter of the Co/CNTs increased from 11.2 to 17.8 nm.Although,the initial FT activity of the Co/CNTs was 26% higher than that of the Co/γ-Al2O3,the FT activity over the Co/CNTs after 720 h on stream decreased by 49% and that over the Co/γ-Al2O3 by 32%.For the Co/γ-Al2O3 catalyst 6.7% of total activity loss and for the Co/CNTs catalyst 11.6% of total activity loss cannot be recovered after regeneration of the catalyst at the same conditions of the first regeneration step.It is concluded that using CNTs as cobalt catalyst support is beneficial in carbon utilization as compared to γ-Al2O3 support,but the Co/CNTs catalyst is more susceptible for deactivation. 相似文献