Thermodynamic aspects of chemical reactions have a long history in the physical chemistry literature. In particular, biochemical cycles require a source of energy to function. However, although fundamental, the role of chemical potential and Gibb's free energy in the analysis of biochemical systems is often overlooked leading to models which are physically impossible. The bond graph approach wa...

Cycles in graphs play an important role in many applications, e.g., analysis of electrical networks, analysis of chemical and biological pathways, periodic scheduling, and graph drawing. From a mathematical point of view, cycles in graphs have a rich structure. Cycle bases are a compact description of the set of all cycles of a graph. In this paper, we survey the state of knowledge on cycle bas...

Cycles have a profound role in cellular life at all levels of organization. Well-known cycles in cell metabolism include the tricarboxylic acid and the urea cycle, in which a specific carrier substrate undergoes a sequence of chemical transformations and is regenerated at the end. Other examples include the interconversions of cofactors, such as NADH or ATP, which are present in the cell in lim...

The efficiency of the application of a chemically-modified activated carbon surface was investigated. The purpose of this study was to examine the effect of treatment with CaCl2 solution at a concentration of 2000 mg.L on the sorption of nitrate ions from aqueous solutions in successive sorption/t reatment cycles. The sorbent was initially subjected to chemical treatment with CaCl2 and subseque...

Thermal engines, particularly closed power cycles, are currently a focus of many studies mainly because they represent the only way to exploit renewable thermal energy. To increase exploitation available sources, this work investigates higher potential offered by complementary technology based on use reactive working fluids instead inert fluids: here-called “thermo-chemical” engine. Such cycle ...

in this paper, we introduce environmental systems engineering (ese) and describe some of its applications combined with process systems engineering (pse) to problems related to environmental systems. these systems—the water cycle and ecosystem cycles—are complex and highly dynamic, with an uncertainty level comparable to that of chemical systems. to illustrate the challenges of applying pse to...

The crack propagation evolution of carbonaceous mudstone under the action dry-wet cycles is an important cause unstable failure this type slope. This paper attempts to reveal mechanism mesocrack and macrocrack in from chemical, physical, mechanical perspectives. Firstly, soaking solution during was extracted for ion concentration test analyze chemical reactions mudstone. Then, CT scans were per...

This paper deals with adjacency matrices of signed cycle graphs and chemical descriptors based on them. The eigenvalues and eigenvectors of the matrices are calculated and their efficacy in classifying different signed cycles is determined. The efficacy of some numerical indices is also examined. Mathematics Subject Classification 2010: Primary 05C22; Secondary 05C50, 05C90

Methylcyclohexane (MCH)-toluene (TOL) chemical hydride cycles as hydrogen carrier systems are successful with the selective dehydrogenation of MCH to TOL, which has been achieved only using precious Pt-based catalysts. Herein, we report improved selectivity using non-precious metal nickel-based bimetallic catalysts, where the second metal occupies the unselective step sites.