WO3–TiO2 monolithic catalysts for high temperature SCR of NO by NH3: Influence of preparation method on structural and physico-chemical properties, activity and durability

2007 ◽  
Vol 72 (3-4) ◽  
pp. 253-261 ◽  
Author(s):  
Motonobu Kobayashi ◽  
Katsunori Miyoshi
Keyword(s):  
High Temperature ◽  
Preparation Method ◽  
Chemical Properties ◽  
Monolithic Catalysts ◽  
Physico Chemical ◽  
Scr Of No

Chitosan-Nanocellulose Composites for Regenerative Medicine Applications

2020 ◽  
Vol 27 (28) ◽  
pp. 4584-4592 ◽  
Author(s):  
Avik Khan ◽  
Baobin Wang ◽  
Yonghao Ni
Keyword(s):  
Regenerative Medicine ◽  
Preparation Method ◽  
Chemical Properties ◽  
Biological Properties ◽  
Next Generation ◽  
Structure Property ◽  
Physico Chemical ◽  
Structure Property Relationship ◽  
Attractive Candidate ◽  
Fundamental Understanding

Regenerative medicine represents an emerging multidisciplinary field that brings together engineering methods and complexity of life sciences into a unified fundamental understanding of structure-property relationship in micro/nano environment to develop the next generation of scaffolds and hydrogels to restore or improve tissue functions. Chitosan has several unique physico-chemical properties that make it a highly desirable polysaccharide for various applications such as, biomedical, food, nutraceutical, agriculture, packaging, coating, etc. However, the utilization of chitosan in regenerative medicine is often limited due to its inadequate mechanical, barrier and thermal properties. Cellulosic nanomaterials (CNs), owing to their exceptional mechanical strength, ease of chemical modification, biocompatibility and favorable interaction with chitosan, represent an attractive candidate for the fabrication of chitosan/ CNs scaffolds and hydrogels. The unique mechanical and biological properties of the chitosan/CNs bio-nanocomposite make them a material of choice for the development of next generation bio-scaffolds and hydrogels for regenerative medicine applications. In this review, we have summarized the preparation method, mechanical properties, morphology, cytotoxicity/ biocompatibility of chitosan/CNs nanocomposites for regenerative medicine applications, which comprises tissue engineering and wound dressing applications.

A New Method of Producing Carbon Anode by High-Temperature Mould Pressing

2011 ◽  
Vol 415-417 ◽  
pp. 611-616
Author(s):  
Yao Wu Wang ◽  
Nai Xiang Feng ◽  
Jing You
Keyword(s):  
High Temperature ◽  
Bulk Density ◽  
Electrical Resistance ◽  
Chemical Properties ◽  
New Method ◽  
Carbon Anode ◽  
Crushing Strength ◽  
Industrial Carbon ◽  
Physico Chemical ◽  
Carbon Anodes

Laboratory-scale carbon anodes were produced by a new method of high-temperature mould pressing, and their physico-chemical properties were studied in laboratory. The results showed that the bulk density of carbon anodes produced by high-temperature mould pressing are 1.61-1.63g/cm3, they are higher than industrial carbon anode by 0.06 g/cm3, but the specific electrical resistance is higher and crushing strength is lower.

The preparation method and composition of the viscose as factors in its physico-chemical properties in the ripening process

1971 ◽  
Vol 3 (6) ◽  
pp. 642-645
Author(s):  
V. G. Kulichikhin ◽  
B. L. Biber ◽  
E. B. Kostikova ◽  
D. N. Arkhangelskii ◽  
M. A. Ginzberg ◽  
...  
Keyword(s):  
Preparation Method ◽  
Chemical Properties ◽  
Ripening Process ◽  
Physico Chemical

scholarly journals The Influence of the Preparation Method on the Physico-Chemical Properties and Catalytic Activities of Ce-Modified LDH Structures Used as Catalysts in Condensation Reactions

Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6191
Author(s):  
Alexandra-Elisabeta Stamate ◽  
Rodica Zăvoianu ◽  
Octavian Dumitru Pavel ◽  
Ruxandra Birjega ◽  
Andreea Matei ◽  
...  
Keyword(s):  
Preparation Method ◽  
Mixed Oxides ◽  
Condensation Reaction ◽  
Chemical Properties ◽  
Precipitation Method ◽  
Synthesis Methods ◽  
Molar Ratios ◽  
Base Catalysts ◽  
Physico Chemical ◽  
Co Precipitation

Mechanical activation and mechanochemical reactions are the subjects of mechanochemistry, a special branch of chemistry studied intensively since the 19th century. Herein, we comparably describe two synthesis methods used to obtain the following layered double hydroxide doped with cerium, Mg3Al0.75Ce0.25(OH)8(CO3)0.5·2H2O: the mechanochemical route and the co-precipitation method, respectively. The influence of the preparation method on the physico-chemical properties as determined by multiple techniques such as XRD, SEM, EDS, XPS, DRIFT, RAMAN, DR-UV-VIS, basicity, acidity, real/bulk densities, and BET measurements was also analyzed. The obtained samples, abbreviated HTCe-PP (prepared by co-precipitation) and HTCe-MC (prepared by mechanochemical method), and their corresponding mixed oxides, Ce-PP (resulting from HTCe-PP) and Ce-MC (resulting from HTCe-MC), were used as base catalysts in the self-condensation reaction of cyclohexanone and two Claisen–Schmidt condensations, which involve the reaction between an aromatic aldehyde and a ketone, at different molar ratios to synthesize compounds with significant biologic activity from the flavonoid family, namely chalcone (1,3-diphenyl-2-propen-1-one) and flavone (2-phenyl-4H-1benzoxiran-4-one). The mechanochemical route was shown to have indisputable advantages over the co-precipitation method for both the catalytic activity of the solids and the costs.

scholarly journals PCL/POSS Nanocomposites: Effect of POSS Derivative and Preparation Method on Morphology and Properties

Polymers ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 33 ◽  
Author(s):  
Mónica Cobos ◽  
Johnny R. Ramos ◽  
Dailyn J. Guzmán ◽  
M. Dolores Fernández ◽  
M. Jesús Fernández
Keyword(s):  
Preparation Method ◽  
Chemical Properties ◽  
Surface Hydrophobicity ◽  
Polyhedral Oligomeric Silsesquioxanes ◽  
Melt Compounding ◽  
Physico Chemical ◽  
Amino Derivatives ◽  
The One ◽  
Crystalline Aggregates

The incorporation of polyhedral oligomeric silsesquioxanes (POSS) molecules as nanoparticles into polymers can provide improved physico-chemical properties. The enhancement depends on the extent of dispersion of the nanofiller, which is determined by the compatibility with the polymer that is by the POSS type, and the processing method. In this study, poly(ε-caprolactone)/POSS derivatives nanocomposites (PCL/POSS) were obtained via solution-casting and melt compounding. Two amino-derivatives containing different alkyl substituents, and ditelechelic POSS-containing hybrid PCL masterbatch were used as nanofillers. The effect of preparation method, POSS content and type on the morphology, thermal, mechanical, and surface properties of nanocomposites were studied. Morphological analysis evidenced the formation of POSS crystalline aggregates, self-assembled POSS molecules of submicrometer size dispersed in the polymer matrix. The best dispersion was achieved using the ditelechelic POSS-containing hybrid PCL masterbatch, and comparing the two amino-POSS derivatives, the one with longer alkyl chain of substituents exhibited better degree of dispersion independent of preparation method. DSC analysis showed the role of POSS derivatives as nucleating agents for PCL. The incorporation of POSS derivatives into the PCL matrix improved thermal stability. The preparation method, POSS type and content had influence on mechanical properties of nanocomposites. POSS nanoparticles enhanced the surface hydrophobicity of PCL.

scholarly journals USING MELT HIGH-TEMPERATURE TREATMENT FOR PROCESSING FOUNDRY WASTES OF HEAT-RESISTANT ALLOY

2019 ◽  
Vol 62 (3) ◽  
pp. 222-227
Author(s):  
A. G. Тyagunov ◽  
Е. Е. Baryshev ◽  
G. V. Tyagunov ◽  
Т. K. Кostina ◽  
K. Yu. Shmakova
Keyword(s):  
High Temperature ◽  
Crystallization Process ◽  
Chemical Properties ◽  
High Temperature Treatment ◽  
Critical Temperatures ◽  
Heat Resistant ◽  
Technical Requirements ◽  
Melt Treatment ◽  
Physico Chemical ◽  
Temperature Dependences

At present time, metallurgical wastes are used in metallurgical alloys production more and more. The volume accumulation and increase of return age effect on charge pollution by undesirable elements and nonmetallic inclusions. As a result, structure and properties of the casting inevitably get worse. This circumstance must influence on polytherm’s character of physical properties of the melt, necessary temperature and time parameters of the heat-resistant alloy’s melting accordingly. We have researched the temperature dependences of electrical resistance and kinematic viscosity of liquid heat-resistant composites based оn Ni – Nb – Cr – Mo systems. The critical temperatures were determined for the EP902 alloy. Heating up to these temperatures leads to irreversible changes in direction of the melt improving. Interaction was found between the amount of foundry waste and features of temperature dependences of the melt physico-chemical properties. An increase in the amount of foundry waste using in remelting results in the critical temperatures increasing. Influence of the melt conditions on crystallization process and on the structure of hard metal has been studied. The process of alloy EР902 solidification was researched by differential thermal analysis method. It has shown that the crystallization process starts with extraction of solid solution on the base of γ-phases and ends with forming of the eutectic based on the Ni3Nb intermetallic compound. Heating of the melt over the critical temperature leads to an increase of supercooling and does not effect on the eutectic temperature. The processing mode of the high temperature melt treatment was proposed based on the research results of physico-chemical properties of the liquid metal and process of the melt crystallization. It allows obtaining the highest quality of casting of heat-resistant EР902 alloy, which contains significant amount of foundry waste in the charge. The mechanical tests were implemented for experimental samples melted out by the optimal mode of high-temperature melt treatment (HTTM). Application of HTTM for the melts, contained 50 % of foundry waste in charge, allows obtaining the level of strength and plastic properties exceeding the technical requirements, stabilizing and combining it from melt to melt.

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