Just One Step (just + one_step)

Distribution by Scientific Domains


Selected Abstracts


Petri net model of protocol conversion for CTF service: its universal coupling criteria and property analysis

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 5 2007
Xiaomin Zhu
Abstract Protocol conversion is a critical issue requiring much research attention. In this paper, the protocol conversion methodology proposed originally by Green is extended with the Petri nets theory to study application layer protocol conversion among more than two interfaces. The click-to-fax (CTF) service based on the Internet intelligent network (IIN) model is taken as an example to illustrate the extended part. A two-step Petri net modelling method is proposed, which is easier compared to constructing the overall model directly in just one step. Universal coupling criteria of Petri net model of protocol conversion (PNPC) are abstracted. The PNPC of CTF service is analysed using analytical techniques of Petri nets, which are proved to be effective in finding and eliminating potential bugs. The necessity of the concept of service layer is also emphasized. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Ultrathin polymeric interpenetration network with separation performance approaching ceramic membranes for biofuel

AICHE JOURNAL, Issue 1 2009
Lan Ying Jiang
Abstract Biofuel has emerged as one of the most strategically important sustainable fuel sources. The success of biofuel development is not only dependent on the advances in genetic transformation of biomass into biofuel, but also on the breakthroughs in separation of biofuel from biomass. The "separation" alone currently accounts for 60,80% of the biofuel production cost. Ceramic membranes made of sophisticated processes have shown separation performance far superior to polymeric membranes, but suffers fragility and high fabrication cost. We report the discovery of novel molecular engineering and membrane fabrication that can synergistically produce polymeric membranes exhibiting separation performance approaching ceramic membranes. The newly discovered Polysulfone/Matrimid composite membranes are fabricated by dual-layer coextrusion technology in just one step through phase inversion. An ultrathin dense-selective layer made of an interpenetration network of the two materials with a targeted and stable interstitial space is formed at the interface of two layers for biofuel separation. The combined molecular engineering and membrane fabrication approach may revolutionize future membrane research and development for purification and separation in energy, environment, and pharmaceuticals. © 2008 American Institute of Chemical Engineers AIChE J, 2009 [source]


Liquid-crystalline thermosets by the curing of dimeric liquid-crystalline epoxyimine monomers with 2,4-toluene diisocyanate

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2003
David Ribera
Abstract We studied the curing processes of several series of dimeric liquid-crystalline epoxyimine monomers with 2,4-toluene diisocyanate (TDI) alone or with added catalytic proportions of 4-(N,N -dimethylamino)pyridine. We obtained isotropic materials or liquid-crystalline thermosets with different degrees of order, which depended on the structures of the monomers. To fix ordered networks, we had to do the curing in two steps when TDI was used alone as the curing agent. However, when a tertiary amine was added in catalytic proportions, the ordered networks were fixed in just one step. In this way, we were able to fix both nematic and smectic mesophases. The significance of the polarization of the mesogen for obtaining liquid-crystalline thermosets was demonstrated. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2521,2530, 2003 [source]


Platinum Nanoelectrodes Embedded in an Insulating Alumina Matrix: An Innovative Approach,

CHEMICAL VAPOR DEPOSITION, Issue 4 2005
A. Battiston
A novel strategy, based on MOCVD, has been employed for preparation of ensembles of platinum nanoelectrodes. Pt/Al2O3 films with different Pt loading were deposited in just one step on glass capillaries. Nanocomposite films with varying Pt/Al atomic ratios were investigated by both cyclic voltammetry and TEM. Ensembles of nanoelectrodes with either overlap or no overlap of the diffusion layers of each nanoelectrode are obtained, depending on the Pt loading. From TEM measurements average Pt particle size of 3 , 7 nm was determined (Figure). [source]