Acidity and Catalytic Activity of Zirconium and Titanium Sulfates Heat-Treated at High Temperature. Solid Superacid Catalysts

1990 ◽  
Vol 63 (1) ◽  
pp. 244-246 ◽  
Author(s):  
Kazushi Arata ◽  
Makoto Hino ◽  
Nobutsugu Yamagata
Keyword(s):  
Catalytic Activity ◽  
High Temperature ◽  
Solid Superacid ◽  
Heat Treated ◽  
Superacid Catalysts

Preparation of solid superacid catalysts by chemical modification of oxides. II.

1991 ◽  
Vol 56 (7) ◽  
pp. 1417-1426
Author(s):  
Tomáš Hochmann ◽  
Karel Setínek
Keyword(s):  
Catalytic Activity ◽  
Chemical Modification ◽  
Lewis Acids ◽  
Solid Superacid ◽  
Acid Properties ◽  
Hydrocarbon Reactions ◽  
Superacid Catalysts

Acid properties of the oxides Al2O3, SiO2, TiO2, SnO2, Sb2O3, ZrO2 and ZrSiO4 were modified by the action of Lewis acids. The acids ( AlCl3, TiCl4, PCl5, SbF5 and P2O5) were deposited on the oxides by sublimation at 150, 250 and 350°C. The strength and number of acid centres of the prepared catalysts and their catalytic activity in hydrocarbon reactions were determined.

Effect of high temperature during grain filling on starch synthesis in the developing barley grain

1998 ◽  
Vol 25 (2) ◽  
pp. 173 ◽  
Author(s):  
M. A. B. Wallwork ◽  
S. J. Logue ◽  
L. C. MacLeod ◽  
C. F. Jenner
Keyword(s):  
Catalytic Activity ◽  
High Temperature ◽  
High Temperatures ◽  
Starch Synthesis ◽  
Grain Filling ◽  
Soluble Starch ◽  
Barley Grain ◽  
Starch Synthase ◽  
Heat Treated ◽  
C 30

Plants of malting barley variety Schooner were exposed to 5 days of high temperatures (up to 35°C) during mid grain filling under controlled environment conditions. Grains from heat treated plants accumulated c. 30% less starch than grains from control plants (21/16°C; 14 h day). Reduced starch deposition was not limited by assimilate levels in heat treated grains, but high temperature reduced the conversion of sucrose to starch. The reduction in starch synthesis appeared to result from the effects of diminished catalytic activity of a number of enzymes in the committed pathway of starch synthesis, and/or delayed recovery of enzyme activity in the cooler recovery conditions. Reductions of 11–75% in the activity of the enzymes under investigation followed high temperature exposure. In addition, ADPglucose pyrophosphorylase, branching enzyme and granule bound starch synthase showed increased activity during exposure to moderate temperatures (28–32°C), but reduced activity at high temperatures, while soluble starch synthase showed an immediate loss of activity, even at moderate temperatures. Sucrose synthase and UDPglucose pyrophosphorylase showed the greatest reduction in catalytic activity after plants were returned to cooler conditions. Individual enzymes showed variation in the level of recovery under the cooler temperature conditions which followed the heating period.

UNS G61200

Alloy Digest ◽  
1991 ◽  
Vol 40 (4) ◽  
Keyword(s):  
Fracture Toughness ◽  
High Temperature ◽  
Heat Treating ◽  
Case Hardening ◽  
Steel Mills ◽  
Temperature Performance ◽  
Treated Condition ◽  
Heat Treated ◽  
High Fatigue ◽  
Heat Treated Condition

Abstract UNS G62100 is a tough, shock resisting, case-hardening chromium-vanadium steel. It has high fatigue resistance in the heat treated condition. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on low and high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: SA-458. Producer or source: Alloy steel mills and foundries.

LUCEFIN GROUP C45U (1.1730)

Alloy Digest ◽  
2020 ◽  
Vol 69 (1) ◽  
Keyword(s):  
High Temperature ◽  
Cold Work ◽  
Hard Case ◽  
Medium Carbon ◽  
Hardened Zone ◽  
Temperature Performance ◽  
Treated Condition ◽  
Heat Treated ◽  
Heat Treated Condition ◽  
Cold Work Tool Steel

Abstract Lucefin Group C45U is a medium-carbon, non-alloy cold-work tool steel. It is primarily used in the non-heat-treated condition. For special applications it is used in the quenched and tempered condition. Owing to its low hardenability, C45U develops a fully hardened zone that is relatively thin, even when quenched drastically. Thicker sections have a hard case over a tough core. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on high temperature performance as well as forming and joining. Filing Code: TS-784. Producer or source: Lucefin S.p.A.

STRESS RELAXATION BEHAVIOUR AND MECHANISM OF HEAT TREATED INCONEL 718 IN HIGH TEMPERATURE ENVIRONMENTS

2013 ◽  
Vol 21 (1) ◽  
pp. 43-51
Author(s):  
O. Bapokutty ◽  
◽  
Z. Sajuri ◽  
J. Syarif ◽  
◽  
...  
Keyword(s):  
High Temperature ◽  
Stress Relaxation ◽  
Inconel 718 ◽  
Relaxation Behaviour ◽  
Heat Treated

From Ru nanoparticle-encapsulated metal–organic frameworks to highly catalytically active Cu/Ru nanoparticle-embedded porous carbon

2017 ◽  
Vol 5 (10) ◽  
pp. 4835-4841 ◽  
Author(s):  
Pradip Pachfule ◽  
Xinchun Yang ◽  
Qi-Long Zhu ◽  
Nobuko Tsumori ◽  
Takeyuki Uchida ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
High Temperature ◽  
Porous Carbon ◽  
Metal Organic Frameworks ◽  
Ammonia Borane ◽  
Carbon Composites ◽  
High Catalytic Activity ◽  
Catalytically Active ◽  
Metal Organic

High-temperature pyrolysis of Ru nanoparticle-encapsulated MOF (Ru@HKUST-1) afforded ultrafine Cu/Ru nanoparticle-embedded porous carbon composites (Cu/Ru@C), which show high catalytic activity for ammonia borane hydrolysis.

The Study on Solid Superacid Synthesis of K12A with Manufacturing Equipment

2012 ◽  
Vol 583 ◽  
pp. 285-288
Author(s):  
Dong Mei Zhao ◽  
Xue Peng Liu
Keyword(s):  
Catalytic Activity ◽  
Metal Oxide ◽  
Design Method ◽  
Orthogonal Design ◽  
Manufacturing Equipment ◽  
Solid Superacid ◽  
Orthogonal Design Method ◽  
Superacid Catalyst ◽  
Calcined Temperature ◽  
Very High

By orthogonal design method, Catalytic activity of /ZrO2 solid superacid is studied, and the influence of catalyst characteristic and structure by manufacturing equipment is issued. It is concluded that the best prepared conditions of the superacid catalyst /ZrO2 for the synthesis of Octyl-Polyglycoside are followed:(1) PH=9.5; (2) calcined temperature at 500; (3) M(H2SO4)=0.5mol/L. Using this kind of catalyst the conversion of glueoside may reach as high as 96% in the synthesis of OCtyl-Polyglycoside and the selectivity is very high for the synthesis of Octyl-Polyglycoside. By introducing other metal oxide, the catalytic activity of complex solid superacid is studied.

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