Dialkyl Carbonate Synthesis via in Situ Generated Carbonyl Dibromide on Porous Glass

The design and construction of an absolute dilatometer of high sensitivity to measure the small expansions resulting from the adsorption of non-polar gases on to porous glass at liquid-air temperatures are described. The expansions measured with this instrument are the first recorded with a rigid adsorbent for the case in which the adsorption is, with certainty, physical in nature. Experiments in which the gases argon, nitrogen, oxygen, hydrogen and krypton were used as adsorbates are reported. The effect of organic matter adsorbed on to the glass from the atmosphere, of unknown composition, on the expansion characteristics is indicated. A technique for the removal of this organic matter in situ without affecting the area of the glass is described. The results have confirmed the correctness of an equation which has been derived by the author (Yates 1952) (∂ F /∂ V ) T = –3/2 K , where ∂ V is the volumetric expansion at constant temperature resulting from ∂ F , the surface free energy lowering, and where K is the bulk modulus of the adsorbent.

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A stimuli responsive material of perovskite quantum dots composited nano-porous glass

Journal of Materials Chemistry C ◽

10.1039/c8tc04383c ◽

2018 ◽

Vol 6 (41) ◽

pp. 11184-11192 ◽

Cited By ~ 10

Author(s):

Yuhong Han ◽

Jiayi Sun ◽

Shi Ye ◽

Qinyuan Zhang

Keyword(s):

Quantum Dots ◽

Porous Glass ◽

Confocal Microscope ◽

Stimuli Responsive ◽

Perovskite Quantum Dots ◽

Responsive Behavior

The water-responsive behavior of the perovskite halides composited porous glass was in situ imaged by a confocal microscope.

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In situ growth of TS-1 on porous glass beads for ammoximation of cyclohexanone

Chemical Engineering Journal ◽

10.1016/j.cej.2013.09.028 ◽

2014 ◽

Vol 235 ◽

pp. 75-82 ◽

Cited By ~ 20

Author(s):

C. Shen ◽

Y.J. Wang ◽

C. Dong ◽

G.S. Luo

Keyword(s):

Porous Glass ◽

Glass Beads ◽

In Situ Growth

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Carbon Nanofibers Grown In Situ on Porous Glass

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.50.1 ◽

2017 ◽

Vol 50 ◽

pp. 1-17

Author(s):

M. Alejandra Mazo ◽

Javier Sanguino ◽

Aitana Tamayo ◽

Juan Rubio

Keyword(s):

Surface Area ◽

Carbon Nanofibers ◽

Porous Glass ◽

Glass Surface ◽

Acid Leaching ◽

Glassy Matrix ◽

Broad Size Distribution ◽

Different Temperatures ◽

20 Nm

Carbon nanofibers (CNFs) were grown in situ on porous glass at different temperatures and times using a Ni acetate catalyst and CH4/N2 as a carbon source. The porous glass was obtained by acid leaching of phase separated borosilicate glass, which generates a broad size distribution of mesopores (≈20 nm). Subsequent impregnation with Ni acetate reduces the pore size to ≈ 4 nm but also creates new micropores, thus increasing the surface area. During thermal treatment the surface area decreases as temperature rises, mainly due to shrinkage of the glassy matrix; however new pores are created at ≈ 70 nm (mainly at 600 oC) associated to the generation of CNFs on the glass surface, indicating this temperature offers the best conditions. The CNFs grow inside and fill in the micro-mesopores in the porous glass. They do not grow at 500 oC as the Ni acetate is not transformed into metallic Ni. Ni deactivation occurs at temperatures over 700 oC, thus reducing the formation of CNFs. At 1000 oC the degradation of CH4 leads to a thickening of the CNFs. The thermal degradation of the CNFs occurs in two steps, the first (360-416oC) corresponding to CNFs grown on the glass surface and the second (518-649oC) to CNFs grown inside the glass pores. Treatment times over 2 h lead to the deactivation of Ni, pore shrinkage and hence lower CNF yields.

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Rendez vous with Saturn's rings

International Astronomical Union Colloquium ◽

10.1017/s0252921100101885 ◽

1984 ◽

Vol 75 ◽

pp. 743-759 ◽

Cited By ~ 2

Author(s):

Kerry T. Nock

Keyword(s):

Solar Energy ◽

Electric Propulsion ◽

Power Source ◽

Propulsion System ◽

Low Thrust ◽

Ring Plane ◽

The Earth ◽

Total Impulse ◽

Saturn's Rings

ABSTRACTA mission to rendezvous with the rings of Saturn is studied with regard to science rationale and instrumentation and engineering feasibility and design. Future detailedin situexploration of the rings of Saturn will require spacecraft systems with enormous propulsive capability. NASA is currently studying the critical technologies for just such a system, called Nuclear Electric Propulsion (NEP). Electric propulsion is the only technology which can effectively provide the required total impulse for this demanding mission. Furthermore, the power source must be nuclear because the solar energy reaching Saturn is only 1% of that at the Earth. An important aspect of this mission is the ability of the low thrust propulsion system to continuously boost the spacecraft above the ring plane as it spirals in toward Saturn, thus enabling scientific measurements of ring particles from only a few kilometers.

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