A porous treasure: Porous aromatic framework PAF‐1 (see picture, blue structure) has been lithiated, giving a reduced framework with an increased gas storage capacity compared to native PAF‐1 (by 22, 71, and 320 % for H2, CH4, and CO2, respectively). The reduced framework was examined spectroscopically, and the potential hydrogen storage capacity was calculated.

Steigerung durch Reduktion: Die Lithiierung des porösen aromatischen Gerüsts PAF‐1 (blaue Struktur) führt zu einem reduzierten Gerüst mit höherer Gasspeicherkapazität (um 22, 71 und 320 % für H2, CH4 bzw. CO2 im Vergleich zu PAF‐1). Das reduzierte Gerüst wurde spektroskopisch untersucht, und seine potenzielle Wasserstoffspeicherkapazität wurde berechnet.

The metal-organic framework beryllium benzene tribenzoate (Be-BTB) has recently been reported to have one of the highest gravimetric hydrogen uptakes at room temperature. Storage at room temperature is one of the key requirements for the practical viability of hydrogen-powered vehicles. Be-BTB has an exceptional 298 K storage capacity of 2.3 wt % hydrogen. This result is surprising given that the low adsorption enthalpy of 5.5 kJ mol(-1). In this work, a combination of atomistic simulation and continuum modeling reveals that the beryllium rings contribute strongly to the hydrogen interaction with the framework. These simulations are extended with a thermodynamic energy optimization (TEO) model to compare the performance of Be-BTB to a compressed H2 tank and benchmark materials MOF-5 and MOF-177 in a MOF-based fuel cell. Our investigation shows that none of the MOF-filled tanks satisfy the United States Department of Energy (DOE) storage targets within the required operating temperatures and pressures. However, the Be-BTB tank delivers the most energy per volume and mass compared to the other material-based storage tanks. The pore size and the framework mass are shown to be contributing factors responsible for the superior room temperature hydrogen adsorption of Be-BTB.

The steady-state production of a product produced through the growth of microorganisms in a continuous flow bioreactor is presented. A generalised reactor model is used in which both the classic well-stirred bioreactor and the idealised membrane bioreactor are considered as special cases. The reaction is assumed to be governed by Monod growth kinetics subject to non-competitive product inhibition. Inhibition is modelled as a decaying exponential function of the product concentration. This reaction scheme is well documented in the literature, although a stability analysis of the governing equations has not previously been presented. The performance of a well-stirred bioreactor with microorganisms death is also not currently available in the literature. The steady-state solutions for the models have been obtained, and the stability has been determined as a function of the residence time. The key dimensionless parameter (γ ) that controls the degree of non-competitive product inhibition is obtained by scaling of the equations, and its effect on the reactor performance is quantified in the limit when product inhibition is 'small'. The parameter γ is a scaled inhibition constant (K p ) that depends upon the substrate and product yield factors and the Monod constant

The steady-state production of a product produced through the growth of microorganisms in a continuous flow bioreactor is presented. A generalised reactor model is used in which both the classic well-stirred bioreactor and the idealised membrane bioreactor are considered as special cases. The reaction is assumed to be governed by Monod growth kinetics subject to non-competitive product inhibition. Inhibition is modelled as a decreasing linear function of the product concentration with a finite cut-off. This reaction scheme is well documented in the literature, although a stability analysis of the governing equations has not previously been presented.The steady-state solutions for the models have been obtained, and the stability has been determined as a function of the residence time. The key dimensionless parameter (γ ) that controls the degree of non-competitive product inhibition is obtained by scaling of the equations, and its effect on the reactor performance is quantified in the limit when product inhibition is 'small' and 'large'. The parameter γ is the reciprocal of a scaled inhibition constant (P m ) that depends upon the substrate and product yield factors and the Monod constant (γ = α s α p · K s P m ).  352 346 Asia-Pacific Journal of Chemical Engineering AN ANALYSIS OF CONTINUOUS FLOW BIO-REACTORS WITH COMPETITIVE Stability of the washout solutionThe Jacobian matrix evaluated at the washout steadystate solution is given by J (S * 0 , 0, 0) =

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Nanospace governs the dynamics of physical, chemical, material and biological systems, and the facility to model it with analytical formulae provides an essential tool to address some of the worlds' key problems such as gas purification, separation and storage. This paper aims to provide some analytical models to exploit building blocks representing various geometric shapes that describe nanostructures. In order to formulate the various building blocks, we use the continuous approximation which assumes a uniform distribution of atoms on their surfaces. We then calculate the potential energy of the van der Waals interaction between an atom and the structure to evaluate the location of the atom where the potential energy is at its minimum. We provide applications of the analytical models for some real structures where more than one type of building block is required.2010 Mathematics subject classification: 5100.