scholarly journals Comparative hydrogenation of the sunflower oil on platinum and nickel catalysts

2017 ◽  
pp. 4-13
Author(s):  
Kainaubek Toshtay ◽  
Ali Auyezov ◽  
Christophe Geantet
Keyword(s):  
Electron Microscopy ◽  
Platinum Catalyst ◽  
Solid Fat Content ◽  
Nickel Catalysts ◽  
Ni Catalyst ◽  
X Ray Diffraction ◽  
Adsorption Method ◽  
Supported Platinum ◽  
Transmission Electron ◽  
Hydrogenation Reactions

The paper considers the diatomite-supported platinum catalyst (1.0 wt% Pt/D) synthesized using colloid adsorption method. The catalyst was characterized by X-ray diffraction, N2 adsorption (BET), scanning electron microscopy and transmission electron microscopy. The activity of the platinum catalyst was investigated by sunflower hydrogenation at 0.5 MPa hydrogen pressure at temperature range from 90°C to 130°C and compared to a commercial Ni catalyst. All of the hydrogenation reactions were terminated at iodine value between approximately 72-86. The results demonstrated that Pt/diatomite catalyst exhibited the highest activity and selectivity at low temperature than the Ni catalyst in hydrogenation processes. Physical characteristics of hydrogenated products such as melting point and solid fat content were also examined.

scholarly journals Synthesis and Characterization of Chitosan-Polyaniline-Manganese Dioxide Nanocomposite for Removal of Methyl Orange Dye

2021 ◽  
Vol 33 (3) ◽  
pp. 671-676
Author(s):  
B.R.S. Rathore ◽  
N.P.S. Chauhan ◽  
M.K. Rawal ◽  
S.C. Ameta ◽  
R. Ameta
Keyword(s):  
Electron Microscopy ◽  
Methyl Orange ◽  
Manganese Dioxide ◽  
Oxygen Demand ◽  
Batch Adsorption ◽  
Significant Shift ◽  
X Ray Diffraction ◽  
Adsorption Method ◽  
Transmission Electron ◽  
Methyl Orange Dye

An ecofriendly polymer composite based on chitosan, polyaniline and manganese dioxide has been prepared using batch adsorption method and analyzed by Fourier transform infrared (FTIR), UV-vis, X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). FTIR results suggested the presence of functional groups like hydroxyl and amino groups and also shown a significant shift in IR bands in CS-PANI-MnO2 composite. The surface of composite was quite rough within the folds of pleated regions as observed from the SEM and TEM morphologies. The prepared composite was also utilized as an adsorbent for the treatment of methyl orange from the aqueous solution and achieved a reasonably good adsorption capacity of 96.2%. The biochemical oxygen demand (BOD) and chemical oxygen demand (COD) tests also suggested their suitability for the adsorption of methyl orange dye.

scholarly journals Synthesis, Characterization, and Catalytic Properties of Magnetic Fe3O4@FU: A Heterogeneous Nanostructured Mesoporous Bio-Based Catalyst for the Synthesis of Imidazole Derivatives

2020 ◽  
Vol 8 ◽  
Author(s):  
Maryam Banazadeh ◽  
Sara Amirnejat ◽  
Shahrzad Javanshir
Keyword(s):  
Electron Microscopy ◽  
Reaction Times ◽  
Sulfated Polysaccharide ◽  
X Ray Diffraction ◽  
Adsorption Method ◽  
Environmental Friendliness ◽  
X Ray ◽  
Transmission Electron ◽  
Ft Ir

In this protocol, Fucoidan (FU), a fucose-rich sulfated polysaccharide extracted from brown algae Fucus vesiculosus was used for in situ preparation of magnetic Fe3O4@FU. Nanoco magnetic properties of Fe3O4@FU were investigated by energy dispersive X-ray (EDX) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) adsorption method, and vibrating sample magnetometer (VSM). The catalytic activity of Fe3O4@FU was employed for the synthesis of tri- and tetra-substituted imidazoles through three- and four-component reactions respectively, between benzyl, aldehydes, NH4OAc and benzyl, aldehydes, NH4OAc, and amine under reflux in ethanol. It is worth nothing that excellent yields, short reaction times, chromatography-free purification, and environmental friendliness are highlighted features of this protocol.

A High Resolution Study of G.P. Zones in Aluminum - 4.2 at % Silver

1982 ◽  
Vol 40 ◽  
pp. 722-723 ◽  
Author(s):  
R. Gronsky
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Computer Simulations ◽  
Structural Characteristics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Resolution Study

The phenomenon of clustering in Al-Ag alloys has been extensively studied since the early work of Guinierl, wherein the pre-precipitation state was characterized as an assembly of spherical, ordered, silver-rich G.P. zones. Subsequent x-ray and TEM investigations yielded results in general agreement with this model. However, serious discrepancies were later revealed by the detailed x-ray diffraction - based computer simulations of Gragg and Cohen, i.e., the silver-rich clusters were instead octahedral in shape and fully disordered, atleast below 170°C. The object of the present investigation is to examine directly the structural characteristics of G.P. zones in Al-Ag by high resolution transmission electron microscopy.

Identification of calcium oxalate crystals in dried or fixed tobacco leaf

1984 ◽  
Vol 42 ◽  
pp. 288-289
Author(s):  
Vicki L. Baliga ◽  
Mary Ellen Counts
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Growth And Development ◽  
Polarized Light ◽  
Calcium Oxalate Crystals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

Epitaxy and texture analysis of Bi-Sr-Ca-Cu-O thin films on (100) MgO using Transmission Electron Microscopy

1990 ◽  
Vol 48 (4) ◽  
pp. 68-69
Author(s):  
J. T. Sizemore ◽  
D. G. Schlom ◽  
Z. J. Chen ◽  
J. N. Eckstein ◽  
I. Bozovic ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Critical Currents ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
Cell Axis ◽  
Transmission Electron ◽  
Synthesis Procedure

Investigators observe large critical currents for superconducting thin films deposited epitaxially on single crystal substrates. The orientation of these films is often characterized by specifying the unit cell axis that is perpendicular to the substrate. This omits specifying the orientation of the other unit cell axes and grain boundary angles between grains of the thin film. Misorientation between grains of YBa2Cu3O7−δ decreases the critical current, even in those films that are c axis oriented. We presume that these results are similar for bismuth based superconductors and report the epitaxial orientations and textures observed in such films.Thin films of nominally Bi2Sr2CaCu2Ox were deposited on MgO using molecular beam epitaxy (MBE). These films were in situ grown (during growth oxygen was incorporated and the films were not oxygen post-annealed) and shuttering was used to encourage c axis growth. Other papers report the details of the synthesis procedure. The films were characterized using x-ray diffraction (XRD) and transmission electron microscopy (TEM).

Devitrification products of rapidly solidified Ni-Nb amorphous alloys.

1990 ◽  
Vol 48 (4) ◽  
pp. 950-951
Author(s):  
G. A. Bertero ◽  
W.H. Hofmeister ◽  
N.D. Evans ◽  
J.E. Wittig ◽  
R.J. Bayuzick
Keyword(s):  
Electron Microscopy ◽  
Amorphous Structure ◽  
Sulphuric Acid Solution ◽  
X Ray Diffraction ◽  
High Fracture ◽  
Transmission Electron ◽  
Xrd Techniques ◽  
Rapidly Solidified ◽  
Electromagnetically Levitated

Rapid solidification of Ni-Nb alloys promotes the formation of amorphous structure. Preliminary results indicate promising elastic properties and high fracture strength for the metallic glass. Knowledge of the thermal stability of the amorphus alloy and the changes in properties with temperature is therefore of prime importance. In this work rapidly solidified Ni-Nb alloys were analyzed with transmission electron microscopy (TEM) during in-situ heating experiments and after isothermal annealing of bulk samples. Differential thermal analysis (DTA), scanning electron microscopy (SEM) and x-ray diffraction (XRD) techniques were also used to characterize both the solidification and devitrification sequences.Samples of Ni-44 at.% Nb were electromagnetically levitated, melted, and rapidly solidified by splatquenching between two copper chill plates. The resulting samples were 100 to 200 μm thick discs of 2 to 3 cm diameter. TEM specimens were either ion-milled or alternatively electropolished in a methanol-10% sulphuric acid solution at 20 V and −40°C.

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