Glucose transformations over a mechanical mixture of ZnO and Ru/C catalysts: Product distribution, thermodynamics and kinetics

2021 ◽  
Vol 405 ◽  
pp. 126945
Author(s):  
Atte Aho ◽  
Simon Engblom ◽  
Kari Eränen ◽  
Vincenzo Russo ◽  
Päivi Mäki-Arvela ◽  
...  
Keyword(s):  
Product Distribution ◽  
Mechanical Mixture ◽  
Thermodynamics And Kinetics

Irradiation behavior of pyrolytic silicon carbide

1983 ◽  
Vol 41 ◽  
pp. 72-73
Author(s):  
R. J. Lauf
Keyword(s):  
Silicon Carbide ◽  
Fission Products ◽  
Thermodynamics And Kinetics ◽  
Neutron Fluences ◽  
Fuel Particles ◽  
Sic Coatings ◽  
Irradiation Behavior ◽  
Kinetics Of ◽  
Htgr Fuel

Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain a layer of pyrolytic silicon carbide to act as a miniature pressure vessel and primary fission product barrier. Optimization of the SiC with respect to fuel performance involves four areas of study: (a) characterization of as-deposited SiC coatings; (b) thermodynamics and kinetics of chemical reactions between SiC and fission products; (c) irradiation behavior of SiC in the absence of fission products; and (d) combined effects of irradiation and fission products. This paper reports the behavior of SiC deposited on inert microspheres and irradiated to fast neutron fluences typical of HTGR fuel at end-of-life.

Use of thermomechanical pulp fibers from waste woods for making eco-friendly cushioning material

TAPPI Journal ◽  
2010 ◽  
Vol 9 (7) ◽  
pp. 15-21 ◽  
Author(s):  
JI-YOUNG LEE ◽  
CHUL-HWAN KIM ◽  
JEONG-MIN SEO ◽  
HO-KYUNG CHUNG ◽  
KYUNG-KIL BACK ◽  
...  
Keyword(s):  
Impact Test ◽  
Product Distribution ◽  
Expanded Polystyrene ◽  
Thermomechanical Pulp ◽  
Fiber Structure ◽  
Pulp Fibers ◽  
Cationic Starch ◽  
Thermal Insulating ◽  
Surface Sizing ◽  
The Impact

Eco-friendly cushioning materials were made with thermomechanical pulps (TMPs) from waste woods collected from local mountains in Korea, using a suction-forming method without physical pressing. The TMP cushions had superior shock-absorbing performance, with lower elastic moduli than expanded polystyrene (EPS) or molded pulp. Even though the TMP cushions made using various suction times had many voids in their inner fiber structure, their apparent densities were a little higher than that of EPS and much lower than that of molded pulp. The addition of cationic starch contributed to an increase in the elastic modulus of the TMP cushions without increasing the apparent density, an effect which was different from that of surface sizing with starch. In the impact test, the TMP cushions showed a more ductile pattern than the brittle EPS. The porosity of the TMP cushion was a little less than that of EPS and much greater than that of molded pulp. The porous structure of the TMP cushions contributed to their excellent thermal insulating capacity, which was equivalent to that of EPS. In summary, the TMP packing cushions showed great potential for surviving external impacts during product distribution.

An NBO-TS predictive approach for torquoselectivity of ring opening in 3-substituted cyclobutenes

2017 ◽  
Author(s):  
Arpita Yadav ◽  
Dasari L V K Prasad ◽  
Veejendra Yadav
Keyword(s):  
Transition State ◽  
Ring Opening ◽  
Natural Bond Orbital ◽  
Theoretical Calculations ◽  
Lone Pair ◽  
Product Distribution ◽  
Acceptor Substituent ◽  
Important Contributor ◽  
Predictive Approach ◽  
Donor Substituent

<p>The torquoselectivity, the inward or outward ring opening of 3-substituted cyclobutenes, is conventionally guided by the donor and/or acceptor ability of the substituent (S). It is typically predicted by estimating the respective ring opening transition state (TS) barriers. While there is no known dissent in regard to the outward rotation of electron-rich substituents from the approaches of TS calculations, the inward rotation was predicted for some electron-accepting substituents and outward for others. To address this divergence in predicting the torquoselectivity, we have used reliable orbital descriptors through natural bond orbital theoretical calculations and demonstrated that (a) interactions <i>n</i><i><sub>S</sub></i>→s*<sub>C3C4</sub> for a lone pair containing substituent, s<sub>S</sub>→s*<sub>C3C4</sub> for a s-donor substituent, s<sub>C3C4</sub>→p*<sub>S</sub> for a resonance-accepting substituent and s<sub>C3C4</sub>→s*<sub>S</sub> for a s-acceptor substituent constitute the true electronic controls of torquoselectivity, and (b) reversibility of the ring opening event is an additional important contributor to the observed product distribution.</p>

Thermodynamics and kinetics of hydriding of the Zr(Ni0.75V0.25)2 laves phase

2004 ◽  
Vol 29 (2) ◽  
pp. 1-9
Author(s):  
Mustapha Boulghallat ◽  
Ahmed Jouaiti ◽  
Norbert Gérard
Keyword(s):  
Laves Phase ◽  
Thermodynamics And Kinetics ◽  
Kinetics Of

Structure and properties of gas-dynamic coatings and evaluation of their use in sliding friction pairs

2020 ◽  
pp. 260-266
Author(s):  
V.E. Arkhipov ◽  
T.I. Murav’eva ◽  
M.S. Pugachev ◽  
O.O. Shcherbakova
Keyword(s):  
Aluminum Oxide ◽  
Sliding Friction ◽  
Metal Layer ◽  
Structural Phase ◽  
Mechanical Mixture ◽  
Structural Factors ◽  
Coating Structure ◽  
Corundum Structure ◽  
Deposited Metal ◽  
Copper Zinc

The problems of changes in the coating structure depending on the composition of the sprayed mechanical mixture using copper particles and mixture of copper and zinc particles (" brass") and the effect of structural factors on the tribological properties of the deposited metal layer are considered. The results of X-ray structural, phase, chemical and durometric analyzes, as well as tribological testing of coatings are presented. It is found that structure with hardness of ≈102.7 HV is formed in the coating from mechanical mixture of particles of copper and aluminum oxide (corundum). Numerous pores are observed in the structure of the deposited metal layer, the main size of which does not exceed 2 μm. In the coating from mechanical mixture of particles copper, zinc and aluminum oxide (corundum), structure is formed based on copper with hardness of ≈106.5 HV, zinc — ≈49.7 HV, intermetallic compounds (γ- and ε-phases) — ≈168.7 HV, the mass fraction of which is 62.0, 7.9 and 24.2 %, respectively. Both coatings can be used in sliding friction pairs.

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