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The self-assembly of an amino-acid substituted tetraphenylethylene (TPE) into a hydrogen-bonded dimeric capsule and an aggregate is reported. Depending on the conditions applied they exhibit bluish photoluminescence with QYs up to 24%.

Czwarta rewolucja przemysłowa i związana z nią transformacja cyfrowa rozwija się niezwykle dynamicznie wprowadzając istotne ulepszenia w przemyśle. Szczególnie obecna jest w procesach wytwórczych, zmieniając w sposób fundamentalny funkcjonowanie przedsiębiorstw. Jednak wiele rozwiązań technologicznych stosowanych w tym obszarze może być z powodzeniem wykorzystane również na innych płaszczyznach. Jedną z nich są siły zbrojne. W artykule autorzy dokonali analizy przykładowego procesu funkcjonowania żołnierzy w toku co-dziennego porządku dnia aby wskazać, że możliwie jest zastosowanie prostych rozwiązań z zakresu elektronicznego zbierania danych i uzyskanie wymiernych korzyści. Tak też określono główny cel badania. Aby go zrealizować autorzy dokonali szczegółowej analizy i oceny wy-branego procesu (ewidencjonowanie faktu opuszczania pododdziału przez podchorążych) wskazując jego niedoskonałości. Na tej podstawie zaproponowali rozwiązanie optymalizujące jego najważniejsze parametry (czas, niezawodność). Zaproponowane rozwiązanie, polegające na wykorzystaniu rejestratorów zbliżeniowych i błyskawicznym odczycie danych wychodzącego żołnierza pozwoliło na rozwiązanie problemu badawczego tj. odpowiedzi na pytanie: czy możliwe i zasadne jest wsparcie wybranych procesów funkcjonowania żołnierzy na pododdziale z wykorzystaniem nowoczesnych narzędzi przemysłu 4.0? Pozwoliło to zweryfikować hipotezę badawczą zakładającą, że zastosowanie prostych narzędzi wykorzystujących nowe technologie może w istotny sposób usprawnić funkcjonowanie badanego procesu. Osiągnięcie założonego celu badania było możliwe dzięki wykorzystaniu takich metod, narzędzi i technik badawczych jak analiza literatury, synteza, metoda obserwacyjna, analiza statystyczna, porównanie i wnioskowanie. Artykuł składa się ze wstępu a następnie z przeglądu literatury z obszaru zarówno rewolucji przemysłowej jak i modernizacji sił zbrojnych. Zasadniczą część stanowi badanie statystyczne czasów trwania procesu wypisywania się podchorążych w niezbędnej dokumentacji podczas opuszczania miejsca zakwaterowania, jego charakterystyka i ocena. Na tej podstawie zaproponowano możliwe rozwiązanie stwierdzonych niedociągnięć. Artykuł wieńczy podsumowanie przeprowadzonych analiz i wnioski końcowe, a także rekomendacje w zakresie dal-szych analiz.

A series of switchable polymeric materials based on Ag(i), Pd(ii) and Pt(ii) and ambidentate ligand has been synthesized and showed enhanced catalytic activity in Heck reaction in comparison with their mononuclear counterparts.

Hydrogen-bonded polymers are a class of highly dynamic supramolecular aggregates, whose self-assembly may be tuned by very mild external or internal stimuli. However, the rational design of chiral supramolecules remains challenging especially when flexible components are involved. The combination of the inherent weakness and dynamic nature of the intermolecular bonds that hold together such assemblies with unrestricted molecular motions introduces additional factors which may affect the self-assembly process. In this report the self-assembly of four amino acid-derived chiral biphenyldiimides into open-chain 1D supramolecular polymers is presented. While the primary driving force, COOH···HOOC hydrogen bonding, is responsible for the polymer growth in all cases, the amino acid side chains play an important role in either stabilizing or destabilizing the assemblies obtained, as deduced from studies of the thermodynamics of the self-assembly process. Furthermore, substantial differences in the structural factors governing the polymerization process between dynamic liquid and static solid are found. This work demonstrates the potential of the rather unexplored class of diimide-based organic dyes in the formation of well-organized chiral supramolecular assemblies with tunable properties.

Here, we report a reaction cascade employing the substituent-induced post-assembly modification of a Co(iii) complex. Unexpectedly, we found that the (triisopropylsilyl)alkynyl moiety introduced to the Sonogashira reaction with the bromo-functionalized Co(iii) assembly plays a "Trojan horse" role, triggering a subsequent, second step of the cascade, i.e. Co(iii) to Co(ii) reduction. The reported substituent-activated Sonogashira-redox cascade reaction might set a new direction in the construction of specific chemical sensors.

We report herein a facile and widely applicable microwave-assisted protocol for the synthesis of symmetrical diimides based on three structurally distinct aromatic dianhydrides: pyromellitic (PMA), biphenyl-tetracarboxylic acid (BPDA) and benzophenone-tetracarboxylic (BTDA) and five natural amino acids (Phe, Tyr, Ile, Lys, Cys). Fifteen symmetrical diimides with different structural characteristics containing a variety of functional groups can be produced with high yields and on a large scale.

International audience; Small π-conjugated molecules can be designed and synthesized to undergo controlled self-assembly forming low-dimensional architectures, with programmed order at the supramolecular level. Such order is of paramount importance because it defines the property of the obtained material. Here, we have focused our attention to four pyromellitic diimide derivatives exposing different types of side chains. The joint effect of different noncovalent interactions including π–π stacking, H-bonding, and van der Waals forces on the four derivatives yielded different self-assembled architectures. Atomic force microscopy studies, corroborated with infrared and nuclear magnetic resonance spectroscopic measurements, provided complementary multiscale insight into these assemblies.

The hierarchical self-assembly of l-tyrosine substituted naphthalenediimide has been explored in solution by NMR spectroscopy and in the solid-state by atomic force microscopy. Spontaneous non-covalent polymerisation led to the formation of a three-dimensional fibre-like supramolecular polymer with n-type semiconducting properties.

The functionalization of a spherical Keplerate-type polyoxometalate {Mo72V30} with a cationic azobenzene surfactant has been achieved through ionic self-assembly. The photoisomerisation reaction of this complex, which emerges in a light-triggered aggregation–disaggregation process, has been followed by 1H NMR spectroscopy, dynamic light scattering, absorption spectroscopy and scanning electron microscopy analyses.

Polycaprolactone (PCL) and polylactide (PLA) are the two most common biodegradable polymers with potential use in oral applications. Both polymers undergo mainly slow hydrolytic degradation in the human body. However, specific conditions of the oral cavity, like elevated temperature, low pH, and presence of saliva affect the rate of hydrolysis. The study examined the properties of solid samples of PCL and PLA subjected to degradation in phosphate buffered saline (PBS) and artificial saliva (AS) at temperatures of 37 or 42 &deg, C, and pH values 2 or 7.4. A number of tests were performed, including measurement of the degree of swelling, weight loss, molecular weight, differential scanning calorimetry, and thermogravimetry of polymers, as well as hardness and tensile strength. Additionally, topography and stiffness of surfaces using atomic force microscopy are presented. It has been noticed that in the artificial saliva, the processes of polymer degradation occur slightly more slowly, and the effects of temperature and pH are less pronounced. We believe that a layer of porcine gastric mucin from artificial saliva that adsorbed on the surface of polymers may have a key role in the observed differences, this layer resembles protective mucin coating tissues in the oral cavity.

Noncovalent self‐assembly creates an effective route to highly sophisticated supramolecular polymers with tunable properties. However, the outcome of this assembly process is highly dependent on external conditions. In this work, a monomeric naphthalene diimide (NDI), designed to allow solubility in a wide range of solvents, can assemble into three distinct noncovalent supramolecular species depending on solvent composition and temperature. Namely, while the self‐assembly in chlorinated solvents yields relatively short, hydrogen‐bonded nanotubes, the reduction of solvent polarity changes the assembly outcome, yielding π–π stacking polymers, which can further bundle into a more complex aggregate. The obtained polymers differ not only in their global morphology but—more strikingly—also in the thermodynamics and kinetics of their supramolecular self‐assembly, involving isodesmic or two‐stage cooperative assembly with kinetic hysteresis, respectively. Ultimately, three distinct assembly states can be accessed in a single experiment.

Packing constellations points in higher dimensions, the concept of multidimensional modulation exploits the idea drawn from geometry for searching dense sphere packings in a given dimension, utilising it to minimise the average energy of the underlying constellations. The following work analyses the impact of spherical shaping of the constellations bound instead of the traditional, hyper-cubical bound. Balanced constellation schemes are obtained with the N-dimensional simplex merging algorithm. The performance of constellations of dimensions 2, 4 and 6 is compared to the performance of QAM modulations of equivalent throughputs in the sense of bits transmitted per complex (two-dimensional) symbols. The considered constellations give an approximately 0:7 dB to 1 dB gain in terms of BER over a standard QAM modulation.

We report on the characterization of two imine type ligands containing photoresponsive azobenzene units as side groups and their transition metal ions complexes. The ligands, both free and in their complexes undergo trans- > cis photoisomerization after irradiation with UV light, but binding of metal ions reduces both the photoisomerisation reaction rates and cis isomer concentrations in the photostationary states. The greatest diminution in the photoisomerisation rate was observed for the complex containing Cd(II), the heaviest among the various transition metal ions tested in this study.

Rationale Compounds containing a urea or thiourea moiety form complexes with anions thanks to the ability to form quite strong hydrogen bonds. We have synthesized 1,3-bis(3-(2-pyridylureido)propyl)-1,1,3,3-tetramethyldisiloxane (1). Compound 1 contains two urea moieties connected by a long flexible linker; thus, it should be able to adopt a structure suitable for formation of quite stable complexes with anions. Methods The ability to form complexes of compound 1 with phosphates was tested by electrospray ionization mass spectrometry (ESI-MS). Full scan ESI mass spectra and collision-induced dissociation tandem mass (CID-MS/MS) spectra of the ions of interest were obtained on a quadrupole time-of-flight (QTOF) mass spectrometer. Results It has been found that compound 1 is not only much more prone to form complexes with the phosphate anion than with other inorganic anions, but it is also able to form complexes with organic phosphates, namely nucleotides and phospholipids. However, compound 1 is not able to form complexes with organic compounds not containing a phosphate group (e.g. nucleosides, sugars, glycerolipids). Conclusions Compound 1 can be regarded as selective towards phosphate-containing organic compounds. Formation of such complexes may have some interesting applications for identification of organic phosphates in crude extracts from biological materials. Copyright © 2015 John Wiley & Sons, Ltd.

We report the synthesis and characterization of a coordination architecture with a Fe(II) center obtained by subcomponent self-assembly in water. The complex is based on very rare hemi-iminal ligands spontaneously generated from commercially available materials. The complex can be further transformed into another species by oxidation reaction of both the metal center and organic ligand.

Self-assembly of multiple building blocks via hydrogen bonds into well-defined nanoconstructs with selective binding function remains one of the foremost challenges in supramolecular chemistry. Here, we report the discovery of a enantiopure nanocapsule that is formed through the self-assembly of eight amino acid functionalised molecules in nonpolar solvents through 48 hydrogen bonds. The nanocapsule is remarkably robust, being stable at low and high temperatures, and in the presence of base, presumably due to the co-operative geometry of the hydrogen bonding motif. Thanks to small pore sizes, large internal cavity and sufficient dynamicity, the nanocapsule is able to recognize and encapsulate large aromatic guests such as fullerenes C60 and C70. The structural and electronic complementary between the host and C70 leads to its preferential and selective binding from a mixture of C60 and C70., Individual hydrogen bonds are weak, so self-assembling multiple components via hydrogen bonding is a significant challenge. Here the authors report a robust, enantiopure nanocapsule held together by 48 cooperative hydrogen bonds, and use it for the selective binding of C70.

We describe here the generation of new donor-acceptor disulfide architectures obtained in aqueous solution at physiological pH. The application of a dynamic combinatorial chemistry approach allowed us to generate a large number of new disulfide macrocyclic architectures together with a new type of [2]catenanes consisting of four distinct components. Up to fifteen types of structurally-distinct dynamic architectures have been generated through one-pot disulfide exchange reactions between four thiol-functionalized aqueous components. The distribution of disulfide products formed was found to be strongly dependent on the structural features of the thiol components employed. This work not only constitutes a success in the synthesis of topologically- and morphologically-complex targets, but it may also open new horizons for the use of this methodology in the construction of molecular machines.

In the second half the 16th century, in Florence, group gathering specialists in the arts, enthusiasts of the antiquity, composers and poets, called Camerata, put examining the ancient culture for herself behind the target. Resurrecting an ancient Greek musical theatre was a basic task of those fans of the antiquity. An opera is a result of those treatments. From very beginning of the creation of the kind, operatic work sought the inspiration in the past. At first they referred to the classical mythology. Then to medieval history and modern history and national mythology. For centuries librettos were the best way of acquainting Europeans with the ancient legacy, history and the European culture. New historiography is combining historiography with literature, emphasizing all at the same time that history isn’t an image of the past. According to Hyden Whte the historical discourse is interpretation. Paul Ricoeur is convincing that a structural sameness is characterizing historiography with the fictional story. One and second are different ways of the narration. Historiography is writing the story which is talking about facts. Similarly is with the opera, being one of the most compound artistic kinds, since is combining features of the, dramatic and musical literary work which manifest itself in the form of the libretto, the music and the drama. Opera is writing and telling a story.