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Hemiporphycene (HPc), a constitutional isomer of porphyrin, is studied under supersonic expansion conditions by means of laser-induced fluorescence (LIF), visible-visible hole-burning experiments, single vibronic level fluorescence (SVLF) techniques, and quantum chemical calculations. Only one trans form of jet-cooled HPc is observed, in contrast with solutions studies that evidence a mixture of two trans tautomeric forms separated in energy by ca. 1 kcal/mol. Reliable structural assignment is provided by simulating absorption and emission patterns at the DFT and TD-DFT levels of theory. The vibronic spectra are nicely reproduced for both electronic ground and lowest excited singlet states for the most stable trans form. In contrast with another porphyrin isomer, porphycene (Pc), no tunneling or photoinduced hydrogen transfer are detected. The lower symmetry of HPc compared with Pc and the concomitant non-equivalent positions of the inner-cavity nitrogen atoms result in a nonsymmetric double minimum potential for tautomerization, larger energy barrier, and a longer tunneling distance, with the average intramolecular hydrogen bonds length larger in HPc than in Pc. HPc readily forms hydrates that show red-shifted absorption relative to the bare molecule.

Making elastomeric composite materials via heteroaggregation of a binary colloidal suspension of Natural Rubber (NR) latex and Carbon Black (CB) filler is an interesting production method to obtain an efficient dispersion in the polymer matrix. This study successfully employs an original approach of field emission scanning electron microscopy (FESEM) to investigate for the first time the nanostructure evolution of a coagulum originated from the aggregation of NR globules with CB filler in suspension. More specifically, we exploited a chemical fixation method allowing simultaneous acquisition of backscattered electron (BSE) and secondary electron (SE) imaging modes. Additionally, the role of external physical stresses, like mechanical shear and sonication was also investigated in terms of structural effect induced on the formed coagulum at the nanoscopic scale. Our results highlight destabilization of NR globules, either induced by direct interaction with small CB aggregates or governed by solvent evaporation. Reduction in the size of CB agglomerates, obtained using sonication, highly improved filler distribution and confirmed that the size of CB aggregates is an important parameter responsible for the destabilization of NR globules.

On 25th September 2015, the Draft Universal Declaration of the Rights of Mankind was presented to the French President François Hollande by the former Minister of Environment Mrs. Corinne Lepage and her team. What is the contribution of this Declaration? What is meant by Rights of Mankind? Are these new rights useful? This article aims to answer these questions by defining the rights of mankind, distinguishing them from human rights and putting them into perspective together with the duties towards mankind. This essay also deals with the institutional implications of this Declaration: Should mankind be represented by some sort of entity or body in order for it to exercise these rights? Who is entitled to speak on behalf of mankind ?Keywords: Universal Declaration of the Rights of Mankind. Draft. Normative and institutional implications.