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Non-photochemical laser-induced nucleation (NPLIN) is a crystallisation method in which a highly structured phase is formed out of solution by exposure to a laser beam. NPLIN offers unprecedented spatiotemporal control and characterisation of nucleation. NPLIN is energy efficient compared to conventional crystallisation methods and can be implemented in continuous microfluidic reactors, enabling sustainable operation. However, its working principles are not yet fully understood. This study contains an evaluation of four proposed mechanisms and a description of an experimental setup involving an ultrahigh speed camera. Two mechanisms describe interaction of molecular polarisation with the electric field, either isotropically known as dielectric polarisation (DP), or anisotropically via the optical Kerr effect (OKE). The other two mechanisms involve cavitation bubble formation by nanoparticle heating through light absorption. This work contains a refined description of this so-called cavity-induced nucleation where its consequences are distinguished into two mechanisms, either based on concentration enhancement (CICEN) or due to pressure enhancement (CIPEN). Novel theoretical calculations in conjunction with experimental data suggest that NPLIN phenomena are based on DP or CICEN, potentially operating in concert. It is conjectured that the influence of DP and CICEN can be quantified further by development of a topological description of DP, simulations of CICEN and relating nucleation probabilities to the metastable zone width of various solutes. The calculations suggest that OKE and CIPEN have little significance because involved energies are several orders of magnitude below kBT . The proposed setup allows for observing the NPLIN phenomena and establishing dependence on cavitation bubbles, providing empirical validation. Solutions to experimental problems are provided, including reduction of sample fluid evaporation, aligning the nucleation site with the reg, LightX, Molecular Science & Technology

Non-photochemical laser-induced nucleation (NPLIN) is a process where a crystalline phase is formed out of solution by exposure to a laser beam. In NPLIN, the nucleation probability is strongly dependent on the beam intensity and weakly dependent on the wavelength. NPLIN offers a feasible alternative to energy-intensive industrial crystallisation methods. Although several mechanisms have been proposed, little is known about NPLIN at the molecular level. Some theories suggest that nucleation rates are enhanced through the heating of nanoparticles by absorption of electromagnetic energy. In this work, molecular dynamics simulations are performed on the clustering of ions in the vicinity of a heated nanoparticle in an aqueous supersaturated KCl solution. The spherical symmetry of a spherical nanoparticle in solution is exploited by modelling a laterally periodic water column of an initial length of 500 Angstrom enclosed between a planar iron(III) oxide nanoparticle surface and a graphene piston. A cavitation bubble is formed after nanoparticle heating, leading to an increase of clustered ions according to a bond order criterion. The clustering should correspond to nucleation in experimental systems because the clusters satisfy Delta G < 0 for locally valid NPT ensembles. The results corroborate concentration based NPLIN mechanisms as the clustering is visibly induced by local solute evaporation. Pressure based mechanisms appear ineffective because no effects of pressure waves are observed. Thermostatting the graphene sheet does not yield observable dissipation of the thermal energy generated through the nanoparticle heating and at the ion clustering sites and, obstructing completion of the cavitation cycle at a feasible simulation duration. It is suggested to repeat the simulations using a conically shaped system and a piston of higher transverse thermal conductivity., Applied Physics

info:eu-repo/semantics/published

Sustainability assessment has emerged as a key decision-support process in development cooperation in response to the growing acknowledgement of the impacts of global change. This paper aims at conceptualizing the effectiveness of sustainability assessment as applied in development cooperation, by focusing on the sustainability assessment practice by actors of the official Belgian Development Cooperation. The conceptualization of the effectiveness of sustainability assessment is synthesized in a set of issues and concerns, based on semi-structured interviews. The paper highlights the specificity of sustainability assessment in the development cooperation sector (e.g. through the cultural and discursive compatibility dimensions of assessment in a North-South context). Effectiveness is inherently linked to the expected functions of sustainability assessment in the decision-making process, which include fostering organizational change, shaping contextually adapted framings of sustainability and operationalizing the sustainability transition. These findings highlight the relevance of a discourse-sensitive approach to sustainability assessment if one is to strengthen its credibility and legitimacy., SCOPUS: ar.j, info:eu-repo/semantics/published

Recognizing the urgent need for sustainability, we argue that to move beyond the rhetoric and to actually realize sustainable development, it must be considered as a decision-making strategy. We demonstrate that sustainability assessment and sustainability indicators can be powerful decision-supporting tools that foster sustainable development by addressing three sustainability decision-making challenges: interpretation, information-structuring, and influence. Particularly, since the 1990s many substantial and often promising sustainability assessment and sustainability indicators efforts are made. However, better practices and a broader shared understanding are still required. We aim to contribute to that objective by adopting a theoretical perspective that frames SA and SI in the context of sustainable development as a decision-making strategy and that introduces both fields along several essential aspects in a structured and comparable manner. © 2014 by the authors., SCOPUS: re.j, info:eu-repo/semantics/published

The purpose of this paper is to identify and assess the implications of sustainable development for the future orientation of higher education, especially after the 2012 United Nations Conference on Sustainable Development (Rio. +. 20). A qualitative trend analysis is being used for this purpose, in the context of which three macro trends are combined: (1) higher education that has been developed via five periods; (2) sustainable development that has evolved through three stages; and (3) the nexus between sustainable development and higher education which has strengthened through three phases. The simultaneous analysis of the macro trends regarding their possible interactive effects (through an expert panel discussion) demonstrates that higher education and universities under the influence of sustainable development elements are entering into a new era in which the function of "higher education for sustainable development" could be interpreted as the seeds of a newly emerging mission for universities. In this regard, it is expected that the concept of "sustainable university" is likely to become more common to meet the emerging mission. Consistent with the Rio. +. 20 outcomes, the authors analyzed the concept of "sustainable university" and identified the fact that it is practically divided into three interrelated and complementary categories, namely social-, environmental-, and economic-oriented university in pursuit of actualizing sustainable development. © 2014 Elsevier Ltd., SCOPUS: ar.j, info:eu-repo/semantics/published

info:eu-repo/semantics/published

European agri-environment programmes are based on the common principle that farmers deliver environmental services for which society pays. Due to the voluntary nature of agri-environment measures (AEM), the issue of farmers' motives or reasons for participation has been an important topic of investigation in past years. The present paper examines farmers' rationale for participation in AEM against the backdrop of continued debate over whether to develop relatively simple measures that can be readily applied by many farmers or give greater priority to measures that are more targeted - i.e. to the specific management requirement of particular habitats or species - but are often more complex. The paper draws on empirical material from a case study in the Dyle valley, Belgium, including in-depth interviews, expert consultations and a mail survey. It was sought not only to identify and quantify the importance of separate reasons for participation, but also to reveal how these reasons and other elements of relevance were logically interrelated in the explanation that farmers themselves give for their participation. As a result, six modes or styles of participation were identified: opportunistic, calculative, compensatory, optimising, catalysing and engaged. The analyses suggest that there were notable differences in that both separate reasons for and modes of participation do vary with the complexity of the measures' requirements. Overall, the study demonstrates that participation in AEM is not simply a matter of weighing the money against the effort for adoption. Whereas money is an important driver for participation (in particular, for those adopting complex AEM) it plays widely differing roles depending on the level of farmers' reasoning (farm enterprise, single practice or landscape feature) and the importance they give to other considerations (environmental effect, production potential of land, goodness of fit, etc.). Practical implications are drawn for both policy

info:eu-repo/semantics/published