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41.
Mohammad Ghashghaee Samira Shirvani Mehdi Ghambarian Ali Eidi 《Petroleum Science and Technology》2019,37(16):1910-1916
A two-stage thermocatalytic upgrading process using a novel catalyst was investigated to produce light olefins and liquid fuels from fuel oil. The upgraded oil from the first thermal stage demonstrated lower viscosity and higher crackability compared to the virgin feedstock. In the next step, the vapor-phase catalytic cracking of the upgraded fraction was implemented over a novel nanoporous composite catalyst, characterized by the XRD, FTIR, NH3- TPD, and N2 physisorption techniques. In total, more than 55?wt% of light olefins, particularly propylene (25.5?wt%) together with 25.4?wt% and 32.5?wt% of gasoline and diesel fuel were obtained in this process. 相似文献
42.
Differential scanning calorimetry (DSC) was used to investigate the protein denaturation characteristics of pork muscles from
four quality groups namely RFN (red, firm, and non-exudative), RSE (red, soft, and exudative), PFN (pale, firm, and non-exudative),
and PSE (pale, soft, and exudative). The thermograms indicated three endothermic peaks between 45°C to 90°C, corresponding
to denaturation of myosin (peak I), sarcoplasmic proteins (peak II), and actin (peak III). The myosin peak was much reduced
in PSE samples, while the actin peak remained almost identical in all groups. RFN and RSE samples were found to have very
similar protein denaturation characteristics and were not significantly different in their thermodynamic protein denaturation
parameters. PFN samples showed similar myofibrilar protein denaturation but significantly different sarcoplasmic protein denaturation
characteristics compared to normal (RFN) samples according to their DSC thermograms. Based on these findings, it was suggested
that the pale color in PFN pork is linked to sarcoplasmic protein denaturation. 相似文献
43.
Juri Saruta Ryotaro Ozawa Takahisa Okubo Samira R. Taleghani Manabu Ishijima Hiroaki Kitajima Makoto Hirota Takahiro Ogawa 《International journal of molecular sciences》2021,22(15)
Biomimetic design provides novel opportunities for enhancing and functionalizing biomaterials. Here we created a zirconia surface with cactus-inspired meso-scale spikes and bone-inspired nano-scale trabecular architecture and examined its biological activity in bone generation and integration. Crisscrossing laser etching successfully engraved 60 μm wide, cactus-inspired spikes on yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) with 200–300 nm trabecular bone-inspired interwoven structures on the entire surface. The height of the spikes was varied from 20 to 80 μm for optimization. Average roughness (Sa) increased from 0.10 μm (polished smooth surface) to 18.14 μm (80 μm-high spikes), while the surface area increased by up to 4.43 times. The measured dimensions of the spikes almost perfectly correlated with their estimated dimensions (R2 = 0.998). The dimensional error of forming the architecture was 1% as a coefficient of variation. Bone marrow-derived osteoblasts were cultured on a polished surface and on meso- and nano-scale hybrid textured surfaces with different spike heights. The osteoblastic differentiation was significantly promoted on the hybrid-textured surfaces compared with the polished surface, and among them the hybrid-textured surface with 40 μm-high spikes showed unparalleled performance. In vivo bone-implant integration also peaked when the hybrid-textured surface had 40 μm-high spikes. The relationships between the spike height and measures of osteoblast differentiation and the strength of bone and implant integration were non-linear. The controllable creation of meso- and nano-scale hybrid biomimetic surfaces established in this study may provide a novel technological platform and design strategy for future development of biomaterial surfaces to improve bone integration and regeneration. 相似文献
44.
Support vector machine based decision for mechanical fault condition monitoring in induction motor using an advanced Hilbert-Park transform 总被引:1,自引:0,他引:1
In this work we suggest an original fault signature based on an improved combination of Hilbert and Park transforms. Starting from this combination we can create two fault signatures: Hilbert modulus current space vector (HMCSV) and Hilbert phase current space vector (HPCSV). These two fault signatures are subsequently analysed using the classical fast Fourier transform (FFT). The effects of mechanical faults on the HMCSV and HPCSV spectrums are described, and the related frequencies are determined. The magnitudes of spectral components, relative to the studied faults (air-gap eccentricity and outer raceway ball bearing defect), are extracted in order to develop the input vector necessary for learning and testing the support vector machine with an aim of classifying automatically the various states of the induction motor. 相似文献
45.
Omnia M. El-Ahwany Ateyya A. Aboul-Enein Samira M. Abdel-Azim Noha A.K. Aboul-Gheit Salah A. Abo-EL-Enein 《Fullerenes, Nanotubes and Carbon Nanostructures》2020,28(6):435-445
AbstractIn this study, Fe–MgO catalyst substrates with various Fe and MgO combinations were evaluated for the growth of different types of carbon nanostructure materials (CNMs), particularly graphene nanoplatelets (GNPs) and carbon nanotubes (CNTs) via chemical vapor deposition using methane as a carbon source. The hydrogen yield was also determined as a valuable by-product in this process. Therefore, a set of Fe–MgO catalysts with different iron loadings (30, 80, 85, 90 and 100?wt %) were prepared by the combustion method to realize this target. The physicochemical properties of freshly calcined Fe–MgO catalysts were investigated by XRD, TPR and BET, while the as-grown CNMs were studied by HR-TEM, XRD and Raman spectroscopy. The results verified that the morphology of as-grown CNMs as well as the H2 yield was directly correlated to the iron content in the catalyst composition. The XRD and TPR results showed that various FeMgOx species with deferent levels of interactions were produced with the gradual incorporation of MgO content. TEM images indicated that GNPs were individually grown on the surface of high loaded iron-containing catalysts (90–100?wt %) due to the presence of highly aggregated iron particles. While multi-walled carbon nanotubes (MWCNTs) with uniform diameters were grown on the low iron-loaded catalyst (30%Fe/MgO) due to the formation of highly dispersed FeMgOx particles. On the other hand, GNPs/MWCNTs hybrid materials were grown on the surface of 80%Fe and 85%Fe/MgO catalysts. This behavior can be interpreted by the co-existence of highly aggregated and highly dispersed Fe2O3 particles in the catalyst matrix. The results demonstrated that the catalyst composition has a notable effect on the nature of CNMs products and H2 yield. 相似文献
46.
Reza Tavakkoli-Moghaddam Samira Vazifeh-Noshafagh Ata Allah Taleizadeh Vahid Hajipour Amin Mahmoudi 《工程优选》2017,49(1):136-160
This article presents a new multi-objective model for a facility location problem with congestion and pricing policies. This model considers situations in which immobile service facilities are congested by a stochastic demand following M/M/m/k queues. The presented model belongs to the class of mixed-integer nonlinear programming models and NP-hard problems. To solve such a hard model, a new multi-objective optimization algorithm based on a vibration theory, namely multi-objective vibration damping optimization (MOVDO), is developed. In order to tune the algorithms parameters, the Taguchi approach using a response metric is implemented. The computational results are compared with those of the non-dominated ranking genetic algorithm and non-dominated sorting genetic algorithm. The outputs demonstrate the robustness of the proposed MOVDO in large-sized problems. 相似文献
47.
The present work reports the synthesis of ZnFe2O4 and ZnO-Zn1-xMxFe2O4+δ (Ln?=?Sm, Eu and Ho) nanomaterials by conventional solid state reactions between Ln2O3, Zn(NO3)2, Fe(NO3)3·9H2O and/or FeCl3·6H2O raw materials at 800?°C for 10?h and 15?h. Stoichiometric and nonstoichiometric reactions were explored for the synthesis of ZnFe2O4. The two Fe sources (Fe(NO3)3 and FeCl3) were used to study the proper raw material type for the synthesis of the ZnFe2O4. The synthesized nanomaterials were characterized by powder X-ray diffraction (PXRD) technique. Rietveld analysis showed that the obtained materials were crystallized well in cubic crystal system with the space group Fd3m and lattice parameters a?=?b?=?c?=?8.4?Å. The rietveld data showed that the purity of ZnFe2O4 was increased from 14% to 88% when the Fe source was changed from FeCl3 to Fe(NO3)3 meanwhile the reaction time was changed from 10 to 15?h. However, the purity was increased to 96% when the stoichiometry of Zn:Fe was changed from 1:2 to 0.8:2 at 800?°C for 15?h. The PXRD data revealed that dopant ion type had a considerable influence on the crystal phase purity of the obtained materials. It was found that Yb2O3 decreased more the purity of the obtained target compared to the other dopant ions. Ultraviolet-visible spectra showed that the synthesized nanomaterials had strong light absorption in the visible light region. Photocatalytic performance of the as-synthesized ZnFe2O4 was investigated for the degradation of pollutant Malachite Green (MG) in aqueous solution under direct visible light irradiation. The degradation yield at the optimized condition (0.09?mL H2O2, 30?mg catalyst and 60?min) was 98%. 相似文献
48.
Ehteram Mohammad Ghotbi Samira Kisi Ozgur EL-Shafie Ahmed 《Water Resources Management》2019,33(15):5207-5230
Water Resources Management - Water allocation is an important issue for systems with multiple stakeholders. Individual and collective decisions are very important for such systems. Thus, a new... 相似文献
49.
Complementary proteomic approaches reveal mitochondrial dysfunction,immune and inflammatory dysregulation in a mouse model of Gulf War Illness 下载免费PDF全文
50.
Maghraoui S Ayadi A Audinot JN Ben Ammar A Jaafoura MH El Hili A Migeon HN Tekaya L 《Microscopy research and technique》2012,75(2):182-188
The subcellular behavior of aluminum and indium, used in medical and industrial fields, was studied in the gastric mucosa and the liver after their intragastric administration to rats, using, two of the most sensitive methods of observation and microanalysis, the transmission electron microscopy, and the secondary ion mass spectrometry. The ultrastructural study showed the presence of electron dense deposits, in the lysosomes of parietal and principal gastric mucosa cells but no loaded lysosomes were observed in the different studied hepatic territories. The microanalytical study allowed the identification of the chemical species present in those deposits as aluminum or indium isotopes and the cartography of their distribution. No modification was observed in control rats tissues. In comparison to previous studies describing the mechanism of aluminum concentration in the gastric mucosa and showing that this element was concentrated in the lysosomes of fundic and antral human gastric mucosa, our study provided additional informations about the types of cells involved in the phenomenon of concentration of aluminum and indium, which are the parietal and the principal cells of the gastric mucosa. Our study demonstrated that these cells have the ability to concentrate selectively aluminum and indium in their lysosomes, as a defensive reaction against intoxication by foreign elements. 相似文献