Results 131 to 140 of about 3,683 (180)
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Age determination of the open cluster NGC 2287 (M41)
Astrophysics and Space Science, 1988We have estimated the age of the open cluster NGC 2287 (M41) by taking into account the rotation of the member stars.
KÜÇÜK, İBRAHİM, ERYURTEZER, D
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Spectroscopic Investigations of Mesoporous M41S Silica Phases
MRS Proceedings, 1994AbstractMesoporous silica phases of the M41S type were investigated by SiK XANES spectroscopy and the results compared with the information provided by 29Si MAS NMR spectroscopy. The results show that the pore walls are more ordered than in “truly” amorphous silica phases (as, e.g., glass) and indicate a relationship of their structure to layered ...
Michael FrÖBa +8 more
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Mesoporous M41S materials in capillary gas chromatography
Chemical Communications, 1997M-41S materials anchored to glass capillary columns via sol–gel techniques can be advantageously utilised for gas chromatographic separations.
M. Raimondo +4 more
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2023
The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements. They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements. They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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Petroleum Science and Technology, 2018
The catalytic cracking of isopropylbenzene was investigaded over hybrid ZSM-12/MCM-41 and HZSM-12/MCM-48 micro-mesoporous materials, in order to verify the effect of the acid site of the accessibil...
Sanny W. M. Machado +6 more
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The catalytic cracking of isopropylbenzene was investigaded over hybrid ZSM-12/MCM-41 and HZSM-12/MCM-48 micro-mesoporous materials, in order to verify the effect of the acid site of the accessibil...
Sanny W. M. Machado +6 more
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The modification of M41S materials: addition of metal clusters and nanoparticles
New Journal of Chemistry, 2010The incorporation of various molecular metal clusters, with well defined stoichiometry, into M41S materials has been investigated. The grafting of simple metal clusters, such as [Ru3(CO)12] and [PPN]2[Fe4(CO)13], and the larger, and in one instance, bimetallic, clusters [(dppe)2Cu][Cu6Fe4(CO)16] and [PPh4][Ru10(μ6-C)(μ-H)(CO)24] has been achieved ...
Nicole S. Hondow +6 more
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Chemical modification of high-quality large-pore M41S materials
Journal of Materials Chemistry, 2002M41S materials with a pore diameter of 80 A and MCM-41 materials with a pore diameter of 30 A were grafted with a variety of trimethoxysilanes and chlorosilanes. The obtained hybrid materials were characterised by thermogravimetric analysis, nitrogen adsorption measurements and multi nuclear MAS NMR.
Benedikt Lindlar +6 more
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ChemInform Abstract: The Synthesis and Properties of M41S and Related Mesoporous Materials
ChemInform, 1998AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
J. C. VARTULI +4 more
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Development of a formation mechanism for M41S materials
19941. Summary The influence of surfactant/silica molar ratio(Sur/Si) in M41S syntheses was studied in the simple synthesis system consisting of tetraethylorthosilicate(TEOS), water, and the cetyltrimethylammonium(CTMA) cation at 100°C. As the Sur/Si increased from 0.5 to 2, the siliceous products obtained were identified and could be classified into ...
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Postsynthesis Hydrothermal Restructuring of M41S Mesoporous Molecular Sieves in Water
The Journal of Physical Chemistry B, 1999A high-quality Si−MCM-41 was prepared with the composition of SiO2, 0.2; TEAOH, 0.25; CTMABr, 35 in H2O using fumed silica as the silica source. The quality of the compounds was assessed using different analytical techniques such as XRD, N2 adsorption−desorption measurement, UV−vis absorption, FTIR, and 29Si MAS NMR.
Laiyuan Chen +3 more
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