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Dr Mounir Maafi

Job: Senior Lecturer

Faculty: Health and Life Sciences

School/department: Leicester School of Pharmacy

Address: 黑料网, The Gateway, Leicester, LE1 9BH.

T: +44 (0)116 257 7704

E: mmaafi@dmu.ac.uk

W: /hls

 

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Personal profile

Mounir Maafi is a senior lecturer at the Leicester School of Pharmacy and he is an active researcher in drugs photostability and stabilisation. He holds an engineer degree from the National Institute of Industrial Chemistry (Algeria), a DEA in Spectrochemical Analysis of Organic and Biological Materials from Paris 6 - Paris 7 Universities, and a PhD in physical/analytical chemistry from Paris 7 University. Dr Maafi has held several Research Fellow/postdoctoral positions including at the Institute of Topology and System Dynamics (Paris, France), the Department of Analytical Chemistry (Badajoz, Spain), the Karolinska Institute at the Karolinska Hospital (Stockholm, Sweden), and at the University of Glamorgan (Cardiff, UK). He has also held university teaching positions as an Associate Professor at Marne La Vallée University, Paris 7 university and CPCM-Paris in France, and at University of Glamorgan at Cardiff. Dr Maafi is an editor for E-Journal of chemistry and a referee for several journals. He speaks five languages and hopes to learn a few more.

Research group affiliations

Chemistry for Health

Publications and outputs


  • dc.title: Photokinetics of Photothermal Reactions dc.contributor.author: Maafi, Mounir dc.description.abstract: Photothermal reactions, involving both photochemical and thermal reaction steps, are the most abundant sequences in photochemistry. The derivation of their rate laws is standardized, but the integration of these rate laws has not yet been achieved. Indeed, the field still lacks integrated rate laws for the description of these reactions鈥� behavior and/or identification of their reaction order. This made difficult a comprehensive account of the photokinetics of photothermal reactions, which created a gap in knowledge. This gap is addressed in the present paper by introducing an unprecedented general model equation capable of mapping out the kinetic traces of such reactions when exposed to light or in the dark. The integrated rate law model equation also applies when the reactive medium is exposed to either monochromatic or polychromatic light irradiation. The validity of the model equation was established against simulated data obtained by a fourth-order Runge鈥揔utta method. It was then used to describe and quantify several situations of photothermal reactions, such as the effects of initial concentration, spectator molecules, and incident radiation intensity, and the impact of the latter on the photonic yield. The model equation facilitated a general elucidation method to determine the intrinsic reaction parameters (quantum yields and absorptivities of the reactive species) for any photothermal mechanism whose number of species is known. This paper contributes to rationalizing photokinetics along the same general guidelines adopted in chemical kinetics. dc.description: open access article

  • dc.title: Editorial: Recent advances in photokinetics dc.contributor.author: Maafi, Mounir dc.description: open access article

  • dc.title: Excitation Wavelength-Dependent Photochemistry dc.contributor.author: Maafi, Mounir dc.description.abstract: The dependence of photochemistry on excitation wavelength is not a recently observed phenomenon; nonetheless, it has, surprisingly enough, been largely ignored in the field. The reasons for this situation are not fully understood but might be related to a provisional extension of Kasha鈥檚 rule to photochemistry, or perhaps to a difficulty to justify the kind of short time-scales implied in such photochemistry, that challenges the usually held view giving predominance to fast internal conversion and vibrational relaxation. Regardless of the reasons, it is still a matter of fact that a complete and satisfactory interpretation for experimentally proven wavelength-dependent photochemistry is not yet available and the community endeavor to build a holistic understanding and a comprehensive view of the phenomenon. The present review is a non-exhaustive overview of the published data in the field, reporting on some of the most prominent features, issues, and interpretations. dc.description: open access article

  • dc.title: On photokinetics under polychromatic light dc.contributor.author: Maafi, Mounir dc.description.abstract: Since the dawn of photochemistry 150 years ago, photoreactions have been conducted under polychromatic light. However, despite the pivotal role that photokinetics should naturally play for such reactive photosystems, the literature lacks a comprehensive description of that area. Indeed, one fails to identify explicit model integrated rate laws for these reactions, a characteristic type for their kinetic behavior, or their kinetic order. In addition, there is no consensus in the community on standardized investigative tools to evaluate the reactivity of these photosystems, nor are there venues for the discussion of such photokinetic issues. The present work is a contribution addressing some of these knowledge gaps. It proposes an unprecedented general formula capable of mapping out the kinetic traces of photoreactions under polychromatic light irradiation. This article quantitatively discusses several reaction situations, including the effects of initial reactant concentration and the presence of spectator molecules. It also develops a methodology for standardizing actinometers and defines and describes both the spectral range of highest reactivity and the photonic yield. The validity of the model equation has been proven by comparing its results to both theoretical counterparts and those generated by fourth-order Runge鈥揔utta numerical calculations. For the first time, a confirmation of the 桅-order character of the kinetics under polychromatic light was established. dc.description: open access article

  • dc.title: On photokinetics under monochromatic light dc.contributor.author: Maafi, Mounir dc.description.abstract: The properties of photokinetics under monochromatic light have not yet been fully described in the literature. In addition, for the last 120 years or so, explicit, handy model equations that can map out the kinetic behaviour of photoreactions have been lacking. These gaps in the knowledge are addressed in the present paper. Several general features of such photokinetics were investigated, including the effects of initial reactant concentration, the presence of spectator molecules, and radiation intensity. A unique equation, standing for a pseudo-integrated rate law, capable of outlining the kinetic behaviour of any photoreaction is proposed. In addition, a method that solves for quantum yields and absorption coefficients of all species of a given photoreaction is detailed. A metric (the initial velocity) has been adopted, and its reliability for the quantification of several effects was proven by theoretical derivation, Runge鈥揔utta numerical integration calculations and through the model equation proposed. Overall, this study shows that, under monochromatic light, photoreaction kinetics is well described by 桅-order kinetics, which is embodied by a unifying model equation. This paper is aimed at contributing to rationalising pho