scholarly journals Direct Synthesis of Ti-Containing CFI-Type Extra-Large-Pore Zeolites in the Presence of Fluorides

Catalysts ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 257
Yichen Wang ◽  
Hongjuan Wang ◽  
Yuanchao Shao ◽  
Tianduo Li ◽  
Takashi Tatsumi ◽  

Ti-containing zeolites showed extremely high activity and selectivity in numerous friendly environmental oxidation reactions with hydrogen peroxide as a green oxidant. It will be in high demand to synthesize Ti-containing crystalline extra-large-pore zeolites due to the severe restrictions of medium-pore and/or large-pore zeolites for bulky reactant oxidations. However, the direct synthesis of extra-large-pore Ti-zeolites was still challengeable. Here, we firstly report a strategy to directly synthesize high-performance Ti-containing CFI-type extra-large-pore (Ti-CFI) zeolites assisted with fluorides. The well-crystallized Ti-CFI zeolites with framework titanium species could be synthesized in the hydrofluoric acid system with seed or in the ammonium fluoride system without seed, which showed higher catalytic activity for cyclohexene oxidation than that synthesized from the traditional LiOH system.

Sungsik Park ◽  
Gakuji Sato ◽  
Ryota Osuga ◽  
Yong Wang ◽  
Yoshihiro Kubota ◽  

2021 ◽  
Vol 5 (1) ◽  
Myungwoo Son ◽  
Jaewon Jang ◽  
Yongsu Lee ◽  
Jungtae Nam ◽  
Jun Yeon Hwang ◽  

AbstractHere, we demonstrate the fabrication of a Cu-graphene heterostructure interconnect by the direct synthesis of graphene on a Cu interconnect with an enhanced performance. Multilayer graphene films were synthesized on Cu interconnect patterns using a liquid benzene or pyridine source at 400 °C by atmospheric pressure chemical vapor deposition (APCVD). The graphene-capped Cu interconnects showed lower resistivity, higher breakdown current density, and improved reliability compared with those of pure Cu interconnects. In addition, an increase in the carrier density of graphene by doping drastically enhanced the reliability of the graphene-capped interconnect with a mean time to failure of >106 s at 100 °C under a continuous DC stress of 3 MA cm−2. Furthermore, the graphene-capped Cu heterostructure exhibited enhanced electrical properties and reliability even if it was a damascene-patterned structure, which indicates compatibility with practical applications such as next-generation interconnect materials in CMOS back-end-of-line (BEOL).

2004 ◽  
Vol 72 (1-3) ◽  
pp. 33-42 ◽  
A.S Maria Chong ◽  
X.S Zhao ◽  
Angeline T Kustedjo ◽  
S.Z Qiao

1986 ◽  
Vol 235 (3) ◽  
pp. 755-761 ◽  
K Miyazaki ◽  
N Okamura ◽  
Y Kishimoto ◽  
Y C Lee

A specific, sensitive and easily performed method for the determination of gangliosides in tissue was developed. After removal of water-soluble compounds, total lipids were extracted from tissue and then treated with 2,4-dinitrophenylhydrazine hydrochloride and dicyclohexylcarbodi-imide in dimethylformamide at 0 degrees C to form ganglioside hydrazides. After removal of excess reagents by column chromatography on silicic acid, the ganglioside 2,4-dinitrophenylhydrazides were eluted from the column and analysed by h.p.l.c. with the use of a silica-gel normal-phase column eluted with an isocratic chloroform/methanol/water/acetic acid system. The addition of CaCl2 improved the separation of GM3 ganglioside containing N-acetylneuraminic acid from that containing N-glycollylneuraminic acid. 2,4-Dinitrophenylhydrazide peaks were measured by the absorbance at 342 nm. Quantification of GM3, GM2, GM1, GD1a, GD1b, GT1b and LM1 gangliosides was linear in a range 0.02-1.6 nmol. GM4, GD3, GT1a and GQ1b gangliosides also yielded distinct peaks, although the range of linearity was not examined. This method was applied to the analysis of the total lipids of rat brain and hepatocytes.

2007 ◽  
Vol 62 (4) ◽  
pp. 180-186 ◽  
Ts. M. Ramishvili ◽  
V. V. Yushchenko ◽  
M. K. Charkviani

ACS Catalysis ◽  
2018 ◽  
Vol 8 (2) ◽  
pp. 1500-1509 ◽  
M. Haris Mahyuddin ◽  
Takahiro Tanaka ◽  
Yoshihito Shiota ◽  
Aleksandar Staykov ◽  
Kazunari Yoshizawa

2019 ◽  
Vol 9 (1) ◽  
Ahmad Asghari ◽  
Mohammadreza Khanmohammadi Khorrami ◽  
Sayed Habib Kazemi

AbstractThe present work introduces a good prospect for the development of hierarchical catalysts with excellent catalytic performance in the methanol to aromatic hydrocarbons conversion (MTA) process. Hierarchical H-ZSM5 zeolites, with a tailored pore size and different Si/Al ratios, were synthesized directly using natural kaolin clay as a low-cost silica and aluminium resource. Further explored for the direct synthesis of hierarchical HZSM-5 structures was the steam assisted conversion (SAC) with a cost-effective and green affordable saccharide source of high fructose corn syrup (HFCS), as a secondary mesopore agent. The fabricated zeolites exhibiting good crystallinity, 2D and 3D nanostructures, high specific surface area, tailored pore size, and tunable acidity. Finally, the catalyst performance in the conversion of methanol to aromatic hydrocarbons was tested in a fixed bed reactor. The synthesized H-ZSM5 catalysts exhibited superior methanol conversion (over 100 h up to 90%) and selectivity (over 85%) in the methanol conversion to aromatic hydrocarbon products.

2019 ◽  
Vol 7 (7) ◽  
pp. 3298-3306 ◽  
Xiaohua Zhang ◽  
Hengxiang Li ◽  
Bing Qin ◽  
Qun Wang ◽  
Xiaohan Xing ◽  

Porous graphitic carbon sheets grafted on microfibers were synthesized with the aid of a green activating–graphitizing agent K3[Fe(C2O4)3].

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