scholarly journals Promoter Effect of Alkali Metal Oxides and Alkali Earth Metal Oxides on Active Carbon-Supported Ruthenium Catalyst for Ammonia Synthesis

1990 ◽  
Vol 63 (4) ◽  
pp. 1221-1225 ◽  
Author(s):  
Ken-ichi Aika ◽  
Toshikazu Kawahara ◽  
Shuzo Murata ◽  
Takaharu Onishi
Keyword(s):  
Alkali Metal ◽  
Metal Oxides ◽  
Active Carbon ◽  
Ammonia Synthesis ◽  
Earth Metal ◽  
Ruthenium Catalyst ◽  
Alkali Earth Metal ◽  
Alkali Earth ◽  
Promoter Effect

Crystallization Behavior and Microstructure of B2O3-Al2O3-SiO2 Glass-Ceramics

2008 ◽  
Vol 51 ◽  
pp. 149-154
Author(s):  
Han Ning Xiao ◽  
Tao Sun ◽  
Hua Bin Liu ◽  
Yin Cheng
Keyword(s):  
Activation Energy ◽  
Metal Oxides ◽  
Crystalline Phase ◽  
Crystallization Behavior ◽  
Glass Ceramics ◽  
Earth Metal ◽  
Crystallization Activation Energy ◽  
Alkali Earth Metal ◽  
Alkali Earth ◽  
Bulk Crystallization

The influences of B2O3/SiO2 ratio and different alkali earth metal oxides MO (M= Ba, Mg, Ca) on the crystallization behavior of B2O3-Al2O3-SiO2 (BAS) glass were investigated by means of DSC, XRD and SEM. With the reduction of B2O3/SiO2 ratio, the crystallization activation energy increases at first and then decreases, reaching the minimum value of 375.4 kJ·mol-1 when the B2O3/SiO2 ratio is 2.2. The crystalline indices (n) are all more than 4, which indicates that the glass is in bulk crystallization. When the glass was heated to 800°C, the primary precipitated crystalline phase was Al4B2O9. With the increase of temperature up to 1100°C, Al18B4O33 and Al5BO9 appeared and became the major crystalline phases in BAS glass-ceramics.

Rb2SeOCl4·H2O: a polar material among the alkali metal selenite halides with a strong SHG response

2016 ◽  
Vol 45 (44) ◽  
pp. 17723-17728 ◽  
Author(s):  
Qi Wu ◽  
Hongming Liu ◽  
Lei Kang ◽  
Zheshuai Lin ◽  
Xianggao Meng ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Alkali Metal ◽  
Earth Metal ◽  
Structure And Properties ◽  
Polar Material ◽  
Alkali Earth Metal ◽  
Alkali Earth

The synthesis, crystal structure and properties of Rb2SeOCl4·H2O, the first polar material among the A–Se–O–X systems (A = alkali metal or alkali-earth metal), is presented. It shows a powder SHG response of 8 times that of KDP.

Platinum doped alkali earth metal oxides as a qubit candidate

2020 ◽  
Vol 181 ◽  
pp. 109754
Author(s):  
Cuiqin Zhou ◽  
Zhenyu Li ◽  
Jinlong Yang
Keyword(s):  
Metal Oxides ◽  
Earth Metal ◽  
Alkali Earth Metal ◽  
Alkali Earth

Microstructure and Crystallization Kinetics Analysis of MO-B2O3-Al2O3-SiO2(M=Mg, Ca, Ba) Glass-Ceramics

2008 ◽  
Vol 368-372 ◽  
pp. 1415-1418
Author(s):  
Hua Bin Liu ◽  
Han Ning Xiao ◽  
Yao Ju Luo ◽  
Hong Wei Liao ◽  
Hai Bo Chen
Keyword(s):  
Activation Energy ◽  
Metal Oxides ◽  
Crystallization Kinetics ◽  
Glass Ceramics ◽  
Earth Metal ◽  
Aluminum Borate ◽  
Kinetics Analysis ◽  
Alkali Earth Metal ◽  
Alkali Earth ◽  
Crystal Phases

The effect of alkali earth metal oxides MO (M=Mg, Ca, Ba) on the crystallizing behavior and the microstructure of B2O3-Al2O3-SiO2 system (BAS) were studied. DSC, XRD and SEM were used to analyze the crystallization kinetics and to characterize the crystal phases and microstructures of the glass-ceramics. MO can effectively facilitate the formation of BAS glass, and the crystallinity of the glass increases in the order of MgO < BaO < CaO. For one given MO, the crystallinity of the glass is dependent on B2O3/SiO2 ratio: the lower the ratio is, the weaker the crystallinity of the glass will be. It was found that the early crystallization is aluminum metaborate (Al4B2O9) when the glass is heated at 800 °C, and it would transfer into aluminum borate(Al18B4O33) at temperatures over 1000 °C. The activation energy and the Avrami exponent of Al4B2O9 were calculated by Ozawa formulation.

Thermal degradation of poly(l-lactide): effect of alkali earth metal oxides for selective l,l-lactide formation

Polymer ◽  
2004 ◽  
Vol 45 (4) ◽  
pp. 1197-1205 ◽  
Author(s):  
Yujiang Fan ◽  
Haruo Nishida ◽  
Tomokazu Mori ◽  
Yoshihito Shirai ◽  
Takeshi Endo
Keyword(s):  
Thermal Degradation ◽  
Metal Oxides ◽  
Earth Metal ◽  
Alkali Earth Metal ◽  
Alkali Earth
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