Effect of crystallization on purity of volatile metallic magnesium prepared from a one-step multi-region condensation process under vacuum condition

SiO2 nanotubes with good chemical purity and well defined morphology were synthesized successfully in a one-step gas phase condensation process using gold catalyst. The as-synthesized products were characterized by transmission electron microscopy and nanoprobe X-ray energy dispersive. In the observations, a growth mechanism of the nanotubes is suggested. The new synthetic route to prepare SiO2 nanotubes is favorable to satisfy the special needs in commercial and industrial application and can be easily applied to other semiconductor materials.

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Electrochemical Properties of Blockcopolymer Templated Mesoporous Silicates with Heteropolyacids clusters

MRS Proceedings ◽

10.1557/proc-756-ee1.10 ◽

2002 ◽

Vol 756 ◽

Author(s):

Hui Suk Yun ◽

Makoto Kuwabara ◽

Hao Shen Zhou ◽

Itaru Honma

Keyword(s):

Electrochemical Properties ◽

Electrode Materials ◽

Precursor Solution ◽

Proton Conductors ◽

Condensation Process ◽

Li Ion Battery ◽

Mesoporous Silicates ◽

Mesoporous Silicate ◽

One Step ◽

Li Ion

ABSTRACTIn this paper, we have studied a method of loading 12-tungstophosphoric acid (H3PW12O40; PWA) into blockcopolymer templated (designated EO20PO70EO20; Pluronic P-123) mesoporous SiO2 framework without a disordering of mesostructure and without remarkable decrease of specific surface area through one-step condensation process. A precursor solution is initially prepared by TEOS (tetraethoxysilane) hydrolyzed with templating polymer (eg. triblock copolymer), and then mixed directly with PWA to condense mesoporous silicate products that incorporate PWA clusters in the framework. Heteropolyanions are possibly incorporated in the framework silicates. Electrochemical properties of these PWA impregnated mesoporous silicates were studied as electrode materials of Li ion battery as well as solid proton conductors.

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First Eu3+@Organo-Si(HIPE) Hybrid Macro-Mesocellular Foams Generation and Associated Luminescent Properties

MRS Proceedings ◽

10.1557/proc-1111-d04-15 ◽

2008 ◽

Vol 1111 ◽

Author(s):

Nicolas Brun ◽

Béatriz Julian-Lopez ◽

Peter Hesemann ◽

Guillaume Laurent ◽

Hervé Deleuze ◽

...

Keyword(s):

Nitrogen Adsorption ◽

Luminescent Properties ◽

Condensation Process ◽

Large Set ◽

Porous Networks ◽

Organically Modified Silicates ◽

Internal Phase ◽

One Step ◽

Emulsion Process ◽

Hybrid Foams

AbstractUsing both β-diketone and malonamide organosilane derivatives and silica Si-HIPE macro-mesocellular foams (acronym refers to the High Internal Phase Emulsion process), organically modified silicates (ORMOSILs) with chelating functionality have been synthesized. The organic functionalities have been anchored to the silica porous networks by both a two-steps grafting method, relating to grafted gOrgano-Si(HIPE), and a one-step co-condensation process, relating to Organo-Si(HIPE). The loading of monoliths by lanthanides was performed by impregnation of an europium (III) salt in solution, leading to a new Eu3+@(g)Organo-Si(HIPE) hybrid foams series. The resulting materials have been thoroughly characterized via a large set of techniques such as SEM, TEM, SAXS, mercury intrusion porosimetry, nitrogen adsorption, FTIR and 29Si CP MAS NMR. Luminescence behavior of this Eu3+@Organo-Si(HIPE) series was also studied and the effects of environment and europium concentration will be discussed.

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An Interactive Minicomputer Program for the Indexing and Simulation of Electron Diffraction Patterns

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092670 ◽

1976 ◽

Vol 34 ◽

pp. 542-543

Author(s):

R.P. Goehner ◽

W.T. Hatfield ◽

Prakash Rao

Keyword(s):

Electron Diffraction ◽

Real Time ◽

Pattern Analysis ◽

Flow Diagram ◽

Hard Copy ◽

Time Analysis ◽

Real Time Analysis ◽

Transmission Electron ◽

One Step ◽

Diffraction Patterns

Computer programs are now available in various laboratories for the indexing and simulation of transmission electron diffraction patterns. Although these programs address themselves to the solution of various aspects of the indexing and simulation process, the ultimate goal is to perform real time diffraction pattern analysis directly off of the imaging screen of the transmission electron microscope. The program to be described in this paper represents one step prior to real time analysis. It involves the combination of two programs, described in an earlier paper(l), into a single program for use on an interactive basis with a minicomputer. In our case, the minicomputer is an INTERDATA 70 equipped with a Tektronix 4010-1 graphical display terminal and hard copy unit.A simplified flow diagram of the combined program, written in Fortran IV, is shown in Figure 1. It consists of two programs INDEX and TEDP which index and simulate electron diffraction patterns respectively. The user has the option of choosing either the indexing or simulating aspects of the combined program.

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Nutrient-regulated gene expression in eukaryotes

Biochemical Society Symposium ◽

10.1042/bss0730085 ◽

2006 ◽

Vol 73 ◽

pp. 85-96 ◽

Cited By ~ 8

Author(s):

Richard J. Reece ◽

Laila Beynon ◽

Stacey Holden ◽

Amanda D. Hughes ◽

Karine Rébora ◽

...

Keyword(s):

Gene Expression ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Transcriptional Control ◽

Direct Interaction ◽

Signalling Pathways ◽

A Cell ◽

One Step ◽

Higher Eukaryotes ◽

Regulated Gene Expression

The recognition of changes in environmental conditions, and the ability to adapt to these changes, is essential for the viability of cells. There are numerous well characterized systems by which the presence or absence of an individual metabolite may be recognized by a cell. However, the recognition of a metabolite is just one step in a process that often results in changes in the expression of whole sets of genes required to respond to that metabolite. In higher eukaryotes, the signalling pathway between metabolite recognition and transcriptional control can be complex. Recent evidence from the relatively simple eukaryote yeast suggests that complex signalling pathways may be circumvented through the direct interaction between individual metabolites and regulators of RNA polymerase II-mediated transcription. Biochemical and structural analyses are beginning to unravel these elegant genetic control elements.

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