3-Homogeneous Groups and Block-Transitive 7–(v, k, 3) Designs

The classification of a block-transitive designs is an important subject on algebraic combinatorics. With the aid of MATLAB software, using the classification theorem of 3-homogeneous permutation groups, we look at the classification problem of block-transitive 7–(v, k, 3) design and prove our main theorem: If the automorphism group of a 7–(v, k, 3) design is block-transitive, then it is neither isomorphic to Affine Type Groups nor Almost Simple Type Groups

The Minimum Merrifield–Simmons Index of Unicyclic Graphs with Diameter at Most Four

The Merrifield–Simmons index iG of a graph G is defined as the number of subsets of the vertex set, in which any two vertices are nonadjacent, i.e., the number of independent vertex sets of G. In this paper, we determine the minimum Merrifield–Simmons index of unicyclic graphs with n vertices and diameter at most four

Fe-Electrocatalytic Deoxygenative Giese Reaction

A redox-neutral Fe-electrocatalytic deoxygenative Giese reaction is reported. Hydroxyl groups are among the most abundant functional groups. The advancement of efficient conversion reactions holds significant importance in medicinal and process chemistry. In this report, we present a redox-neutral Giese reaction via anodic oxidation to generate phosphonium ions and cathodic reduction to yield low-valent Fe catalysts. This reaction constitutes a ground-breaking account of a redox-neutral reaction utilizing Fe-catalyst and electrochemistry. It will facilitate the exploration of diverse novel reactions employing this redox cycle in the future

Enhanced hydrogen sorption on carbon and NiO in the presence of a piezoelectric element

Behaviors of hydrogen sorption on carbon and NiO in the presence of a piezoelectric element were studied. Initiation of this effort was based on the theoretical predictions and experimental evidences that charged species have capabilities to cluster hydrogen molecules. The piezoelectric element is able to autogenously generate charges in hydrogen pressure. Enhanced hydrogen sorption was observed from this study. The observed sorption enhancement supports the assumption that sorbent materials could hold more hydrogen if they are electrically charged. The greater enhancement observed from hydrogen sorption on NiO samples was attributed to the catalysis effect of nickel species, which might split hydrogen molecules into hydrogen atoms and thus make the effect of electric field on hydrogen sorption more effective. © 2009 American Chemical Society

Enhanced hydrogen sorption on carbonaceous sorbents under electric field

The effect of an applied electric field on hydrogen physisorption isotherm on carbonaceous sorbents was studied. Distinctive sorption enhancement was obtained by applying a positive electrical potential of 2000 V to platinum-supported carbon samples. The phenomenon was ascribed to stronger interactions between hydrogen and the sorbent. Theoretical studies suggested that, the interaction between hydrogen and neutral carbon is primarily the electrostatic attraction between the π-bonds of the aromatic rings and the σ-bonds of H2, which is classified as van der Waals interaction and is weak. However, the interaction between electrically charged carbon and hydrogen might involve orbital interactions between hydrogen and carbon, an interaction stronger than van der Waals attraction. Experimental studies indicated that the presence of platinum would induce dissociation of hydrogen molecules in to hydrogen atoms. The easier accessibility of the atomic orbital might favor the electron transfer from the atomic hydrogen to charged carbon. © 2009 Professor T. Nejat Veziroglu

Effect of piezoelectric material on hydrogen adsorption

In hydrogen storage applications, the primary issue for physisorption of hydrogen onto solid-state materials is the weak interaction force between hydrogen molecules and the adsorbents. It is found that enhanced adsorption can be obtained under an external electric field, because it appears the electric field increases the hydrogen adsorption energy. Experiments were carried out to determine hydrogen adsorption on activated carbon using the piezoelectric material PMN-PT as the charge supplier under hydrogen pressure. Results indicate that more than 20% hydrogen adsorption enhancement was obtained. Parameters related to hydrogen adsorption enhancement include the amount of the charge and temperature. Higher voltage and lower temperature promote the increase of adsorption capacity but room temperature results are very encouraging. © 2010 Elsevier B.V. All rights reserved

Effects of electric potential on hydrogen adsorption

Hydrogen adsorption isotherms of activated carbon and its mixture with platinum coated activated carbon under various electric potentials and hydrogen pressures were measured at ambient temperature. Results indicated that electric potential enhanced hydrogen adsorption. The higher the applied electric potential is, the higher the hydrogen adsorption capacity is in the experimental range of 0-3000 V. The total amount of hydrogen adsorption increases with the hydrogen pressure. However, the enhancement is more obvious at hydrogen pressures below 10 bars. The enhancement ratio can reach about 160% at 1.6 bars pressure and 3000 V applied electric potential, but decreases to about 20% at 80 bars pressure under the same voltage. The adsorption enhancement is much more significant for the mixture of platinum coated activated carbon and activated carbon at a ratio of 1-4. At 1.6 bars, the hydrogen adsorption capacity increases from 0.008 wt.% at 0 V to 0.058 wt.% at 2500 V, which is a 625% adsorption enhancement. At 83 bars, the hydrogen adsorption capacity increases from 0.43 wt.% at 0 V to 0.56 wt.% at 2500 V, about 30% adsorption enhancement. © 2009 Elsevier Ltd