Green chemistry preparation of MgO grit like nanostructures: efficient catalyst for the synthesis of 4H-pyrans and α,α′-bis(substituted-benzylidene) cycloalkanone derivatives

2016 ◽  
Vol 5 (3) ◽  
Author(s):  
Akbar Mobinikhaledi ◽  
Atisa Yazdanipour ◽  
Majid Ghashang
Keyword(s):  
Green Chemistry ◽  
Field Emission ◽  
Energy Dispersive ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
One Pot ◽  
Efficient Catalyst ◽  
X Ray ◽  
Edx Analysis

AbstractA grit like nanostructure of MgO was prepared in a medium of mulberry leaves extract and characterized on the basis of field emission scanning electronic microscopy (FE-SEM), X-ray diffraction (XRD), and energy dispersive X-ray (EDX) analysis. It was found to be an efficient catalyst for one-pot synthesis of 4

Field-Emission Scanning Electron Microscopy and Energy-Dispersive X-Ray Analysis to Understand the Role of Tannin-Based Dyes in the Degradation of Historical Wool Textiles

2014 ◽  
Vol 20 (5) ◽  
pp. 1534-1543 ◽  
Author(s):  
Annalaura Restivo ◽  
Ilaria Degano ◽  
Erika Ribechini ◽  
Josefina Pérez-Arantegui ◽  
Maria Perla Colombini
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Elemental Composition ◽  
Field Emission ◽  
Cross Sections ◽  
Morphological Changes ◽  
Energy Dispersive ◽  
X Ray ◽  
Edx Analysis ◽  
Scanning Electron

Abstract:An innovative approach, combining field-emission scanning electron microscopy (FESEM) with energy dispersive X-ray spectroscopy (EDX) analysis, is presented to investigate the degradation mechanisms affecting tannin-dyed wool. In fact, tannin-dyed textiles are more sensitive to degradation then those dyed with other dyestuffs, even in the same conservation conditions.FESEM-EDX was first used to study a set of 48 wool specimens (artificially aged) dyed with several raw materials and mordants, and prepared according to historical dyeing recipes. EDX analysis was performed on the surface of wool threads and on their cross-sections. In addition, in order to validate the model formulated by the analysis of reference materials, several samples collected from historical and archaeological textiles were subjected to FESEM-EDX analysis.FESEM-EDX investigations enabled us to reveal the correlation between elemental composition and morphological changes. In addition, aging processes were clarified by studying changes in the elemental composition of wool from the protective cuticle to the fiber core in cross-sections. Morphological and elemental analysis of wool specimens and of archaeological and historical textiles showed that the presence of tannins increases wool damage, primarily by causing a sulfur decrease and fiber oxidation.

Characterization of Shivirtui Zeolite Modified with Aluminum Oxyhydroxide Nanofibers

2019 ◽  
Vol 942 ◽  
pp. 40-49
Author(s):  
Yulia Murashkina ◽  
Olga B. Nazarenko
Keyword(s):  
Chemical Properties ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Aluminum Oxyhydroxide

Natural zeolite of Shivirtui deposit (Russia) was modified with nanofibers of aluminum oxyhydroxide AlOOH. Aluminum oxyhydroxide nanofibers were produced at the heating and oxidation of aluminum powder with water. The properties of modified zeolite were investigated by means of X-ray diffraction, transmission electronic microscopy, scanning electronic microscopy, low-temperature nitrogen adsorption, thermal analysis, and Fourier transform infrared spectroscopy. It was found that water content in the modified sample of zeolite was about 15 %. Based on the study of the physical and chemical properties, shivirtui zeolite modified with nanofibers of aluminum oxyhydroxide can be proposed for use as a flame-retardant additive to polymers.

The Competitive Growth of BiOI and BiSI in the Solvothermal Process

2011 ◽  
Vol 236-238 ◽  
pp. 1919-1922 ◽  
Author(s):  
Wen Jun Fa ◽  
Pin Jiang Li ◽  
Yan Ge Zhang ◽  
Li Li Guo ◽  
Jia Fan Guo ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Powder Diffraction ◽  
Energy Dispersive ◽  
Solvothermal Process ◽  
Competitive Growth ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray

BiOI nanolamellas and BiSI nanowires were synthesized using Bi(NO3)3·5H2O, (NH2)2CS and I2 as reactants in the solvothermal process with ethanol as the system media. The as-prepared samples were characterized by X-ray powder diffraction (XRD), scanning electronic microscopy (SEM), Energy-Dispersive X-ray Spectrometer (EDS). The competitive growth of BiOI and BiSI were investigated by changing the quantity of (NH2)2CS. A possible reaction mechanism was proposed.

scholarly journals The Dehydrogenation Mechanism and Reversibility of LiBH4 Doped by Active Al Derived from AlH3

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 559 ◽  
Author(s):  
Qing He ◽  
Dongdong Zhu ◽  
Xiaocheng Wu ◽  
Duo Dong ◽  
Xiaoying Jiang ◽  
...  
Keyword(s):  
Reaction Products ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Scanning Calorimetry ◽  
Mass Spectral Analysis ◽  
X Ray ◽  
Mass Spectral ◽  
Al Composite ◽  
Dehydrogenation Mechanism

A detailed analysis of the dehydrogenation mechanism and reversibility of LiBH4 doped by as-derived Al (denoted Al*) from AlH3 was performed by thermogravimetry (TG), differential scanning calorimetry (DSC), mass spectral analysis (MS), powder X-ray diffraction (XRD), scanning electronic microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The results show that the dehydrogenation of LiBH4/Al* is a five-step reaction: (1) LiBH4 + Al → LiH + AlB2 + “Li-Al-B-H” + B2H6 + H2; (2) the decomposition of “Li-Al-B-H” compounds liberating H2; (3) 2LiBH4 + Al → 2LiH + AlB2 + 3H2; (4) LiBH4 → LiH + B + 3/2H2; and (5) LiH + Al → LiAl + 1/2H2. Furthermore, the reversibility of the LiBH4/Al* composite is based on the following reaction: LiH + LiAl + AlB2 + 7/2H2 ↔ 2LiBH4 + 2Al. The extent of the dehydrogenation reaction between LiBH4 and Al* greatly depends on the precipitation and growth of reaction products (LiH, AlB2, and LiAl) on the surface of Al*. A passivation shell formed by these products on the Al* is the kinetic barrier to the dehydrogenation of the LiBH4/Al* composite.

Study of the Synthesis of Mullite From Kaolin-α-Al2O3 and Kaolin-Al(NO3)3

2012 ◽  
Vol 1481 ◽  
pp. 11-17
Author(s):  
E. M. Lozada ◽  
O. Alanís ◽  
F. Legorreta ◽  
L. E. Hernández
Keyword(s):  
Combustion Method ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray ◽  
Crystallographic Study ◽  
Incomplete Reaction ◽  
Α Al2o3

ABSTRACTThe synthesis of mullite from kaolin clay and two precursors of aluminum: α-Al2O3 and Al(NO3)3 was investigated. In order to study the temperature effect, the system kaolin-α-Al2O3 was calcined in air in a range of 1200 to 1500°C, for 2 h. For the system kaolin-Al(NO3)3, the combustion method was employed, using urea as fuel, and calcined in air at 1500°C for 2 h. The products were characterized by X-ray diffraction, scanning electronic microscopy (SEM), energy dispersive spectroscopy and particle size analysis in order to analyze and compare their morphology and structure. The crystallographic study revealed an incomplete reaction between the kaolin and the α-Al2O3. Nevertheless, in the system kaolin-Al(NO3)3, it was obtained mullite with high purity and trace amounts of cristobalite.

Fabrication and Magnetic Properties of Fe3O4 Nanobranches via a Simple Solvothermal Method

2011 ◽  
Vol 335-336 ◽  
pp. 934-939
Author(s):  
Z. F. Zi ◽  
Y. N. Liu ◽  
Q.C. Liu ◽  
Jian Ming Dai ◽  
Yu Ping Sun
Keyword(s):  
Magnetic Properties ◽  
Single Phase ◽  
Solvothermal Method ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray ◽  
Water Solvent ◽  
Phase Spinel ◽  
Antisite Defects

Magnetite (Fe3O4) nanobranches were synthesized using an improved solvothermal technique in mixed ethanol and water solvent. Structural and magnetic properties were systematically investigated. X-ray diffraction results showed that the sample was single-phase spinel structure. The results of scanning electronic microscopy exhibited that the grains were regular like-branch with sizes from 3 to 6 μm in length and in diameter between 50 and 200 nm. The composition determined by energy dispersive spectroscopy was very close to the stoichiometry of Fe3O4. The saturation magnetizations (Ms) at 10 and 300 K of the synthesized Fe3O4nanobranches were much lower than the theoretical values. On one hand, it could be explained by obstructive magnetizing along their non-easy magnetic axes by the shape anisotropy of Fe3O4nanobranches, on the other hand, lesserMscan also be understood by the existence of antisite defects.

scholarly journals The Dehydrogenation Mechanism and Reversibility of LiBH4 Doped by Active Al* Derived from AlH3

2019 ◽  
Author(s):  
Qing He ◽  
Dongdong Zhu ◽  
Xiaocheng Wu ◽  
Duo Dong ◽  
Xiaoying Jiang ◽  
...  
Keyword(s):  
Reaction Products ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Scanning Calorimetry ◽  
Mass Spectral Analysis ◽  
X Ray ◽  
Mass Spectral ◽  
Al Composite ◽  
Dehydrogenation Mechanism

A detailed analysis of the dehydrogenation mechanism and reversibility of LiBH4 doped by active Al* derived from AlH3 was performed by thermogravimetry (TG), differential scanning calorimetry (DSC), mass spectral analysis (MS), powder X-ray diffraction (XRD), scanning electronic microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The results show that the dehydrogenation of LiBH4/Al* is a five-step reaction: (1) LiBH4 + Al → LiH + AlB2 + “Li-Al-B-H” + B2H6 + H2; (2) the decomposition of "Li-Al-B-H" compounds liberating H2; (3) 2LiBH4 + Al → 2LiH + AlB2 + 3H2; (4) LiBH4 → LiH + B + 3/2H2; (5) LiH + Al → LiAl + 1/2H2. And the reversibility of LiBH4/Al* composite is based on equation as follows: LiH + LiAl + AlB2 + 7/2H2 ↔ 2LiBH4 + 2Al. The extent of dehydrogenation reaction between LiBH4 and Al* greatly depends on the precipitation and growth of reaction products (LiH, AlB2 and LiAl, etc.) on the surface of Al*. A passivation shell of Al* formed by these products is the kinetic barrier to the dehydrogenation of LiBH4/Al* composite.

scholarly journals Structure and composition of soils

2010 ◽  
Vol 4 (4) ◽  
pp. 259-263 ◽  
Author(s):  
Snezana Nenadovic ◽  
Milos Nenadovic ◽  
Ljiljana Kljajevic ◽  
Vladimir Pavlovic ◽  
Aleksandar Djordjevic ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Porous Structure ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Characterization Methods ◽  
Soil Particles ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force

This paper presents a study of soils structure and composition using up to date technique, such as scanning electronic microscopy, atomic force microscopy, X-ray diffraction, X-ray fluorescence, as well as some other characterization methods. It was shown that soil particles have porous structure and dimensions in the range from several millimeters to several hundreds of nanometers and consist of different minerals such as kaolin, quartz and feldspate.

Synthesis and Characteristics of Melamine Formaldehyde Composites

2014 ◽  
Vol 1040 ◽  
pp. 393-398 ◽  
Author(s):  
Yakha Visurkhanova ◽  
Nina Ivanova ◽  
Gulsum Tusupbekova ◽  
Daria Izbastenova
Keyword(s):  
Catalytic Activity ◽  
Transition Metals ◽  
X Ray Diffraction ◽  
Melamine Formaldehyde ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray

Melamine formaldehyde composites have been synthesized with chlorides and micro- and nanoparticles of transition metals (Co, Ni, Cu) entered into polymer during the polycondensation of melamine with formaldehyde. The received composites were studied by the X-ray diffraction and scanning electronic microscopy and applied as catalysts to cathode activation in cyclohexanone electrohydrogenation. For composites of MF+MCl2 it was established higher catalytic activity than for МF+М0.

Effect of the Ratio of Zn/Y on Microstructure and Mechanical Properties of As-Cast Mg-4Zn-xY Alloys

2013 ◽  
Vol 395-396 ◽  
pp. 201-204
Author(s):  
Feng Wang ◽  
Ji Bao Li ◽  
Ping Li Mao ◽  
Zheng Liu
Keyword(s):  
Mechanical Properties ◽  
Tensile Testing ◽  
Energy Dispersive Spectrum ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray ◽  
Uniformity Coefficient ◽  
Microstructure And Mechanical Properties ◽  
Second Phases

In order to investigate the ratio of Zn/Y on as-cast Mg-4Zn-xY (x=1, 2, 3 in wt. %), microstructure and mechanical properties are analyzed by scanning electronic microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrum (EDS) and tensile testing. The results indicate that with the decrease of the ratio of Zn/Y, microstructures are refined more greatly and the spheroidization and uniformity coefficient are improved obviously, and the morphologies of second phases are changed from diversity to unity, resulting in an improvement of mechanical properties of alloys.

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