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Luminescent solar concentrators (LSCs) have recently emerged as valuable candidates for the realization of aesthetically pleasing solar windows for near-zero-energy consumption buildings. The growing demand by the building-integrated photovoltaic sector is urging the development of sustainable production methods that minimize the use of polluting organic solvents and hazardous materials, while still enabling industrial-grade LSCs. Here, we introduce a new class of benzothieno-benzothiophene (BTBT) derivatives as highly efficient reabsorption-free emitters for transparent LSCs featuring high stability and a solvent-free chemical access with sustainability factor as low as 21, 10 to 50 times lower than conventional LSC emitters. By embedding our BTBT emitters in optical-grade polymeric waveguides, we produced large-area (40 cm × 40 cm) LSCs with optical power efficiency as high as 3% (corresponding to an optical quantum efficiency of 54%). These results represent an important advancement toward sustainable solar glazing systems for green architecture.The growing demand for building-integrated photovoltaic technologies for near-zero-energy buildings is motivating the scientific community to develop devices that meet the functional, energetic, and aesthetic needs for sustainable architecture. Luminescent solar concentrators (LSCs) are emerging as valuable solutions to realize aesthetically pleasing semitransparent photovoltaic windows capable of converting urban buildings into energy generators. In this work, we report on efficient, transparent LSCs based on a novel class of reabsorption-free derivatives synthesized through a solvent-free route that massively improves the sustainability factor with respect to the state of the art. Optical-grade polymeric LSCs are produced via industrial methods with an optical power efficiency as high as 3% despite their transparency in the visible region. These results represent an important step forward for sustainable solar glazing systems for environmentally friendly architecture. Efficient and aesthetically pleasing solar technologies, such as LSC photovoltaic windows, are becoming essential for the widespread of zero-energy buildings. The more the LSC technology gains appeal, the higher the need becomes for efficient and sustainable materials and production routes. Through a new mechanochemical route, we produce efficient, reabsorption-free LSC emitters with a massively increased sustainability factor. The integration of such derivatives into industrial-grade LSCs leads to an optical efficiency of 3% for large-area devices.

International audience; Radioactive gas monitoring is an important topic for homeland security, medical research and metrology. Our research aims at developing a new ultrasensitive detection system based on timecoincidence techniques exploiting porous scintillators, which enhance the interaction probability of emitted ionizing radiations and concentrate the radioactive material by absorption of gases. Considering their fast scintillation [1] and compositional tunability [2], here highly-porous fluorescent hafnium based metal-organic frameworks nanocrystals are included in a polystyrene aerogel matrix to obtain a hierarchical pore size distribution particularly favorable for gas absorption and realizing a prototype scintillating detector tested for sensing the 85Kr, 222Rn, and 3H radioactive gas species.

The present contribution will be an overview of porous materials as radiation frequency converters, by integration of acceptor and donor into a single framework, for light upgrading and downgrading. Two active components will be co-assembled in varied molar fractions to reach the optimal balance. A few strategies of bond formation will be compared to form mix-ligand MOFs and PAFs. In some instances, even three components, each with its own function, can be comprised in the structures. The chromophore density and the distance between donors and acceptors can be fine-modulated, for benchmark efficiency. Morphology and size of the nanocrystals was also a parameter kept under control and excitation diffusion was modelled. Additionally, dynamics in porous materials will be addressed in detail by spectroscopic techniques: fast molecular reorientation and, specifically, dipole reorientation is a challenging task as explored in conjunction with gas diffusion. CO2 and Xe learn during diffusion steps, the shape and orientation of the channels, as detected by anisotropic line-shape analysis of 13C and hyperpolarized 129Xe NMR resonances. These spectroscopic observations, together with DFT and molecular dynamics simulations, help understand gas sorption and measure diffusion times by jump frequency of the gas species from site to site in the material, through orientation imprinting. Overall, a structure-property comparison among porous systems, from metal-organic to covalent and molecular porous materials, will be traced as regards the potentials to realize the desired performances. 1) Nature Photonics 2021 https://doi.org/10.1038/s41566-021-00769-z 2) Adv. Mater. 2019, 31, 1903309 3) Chem. Sci., 2019, 10, 730

The photon upconversion based on triplet–triplet annihilation (TTA) is a mechanism that converts the absorbed low-energy electromagnetic radiation into higher energy photons also at extremely low excitation intensities, but its use in actual technologies is still hindered by the limited availability of efficient annihilator moieties. We present here the results obtained by the synthesis and application of two new fluorinated chromophores based on phenazine and acridine structures, respectively. Both compounds show upconverted emission demonstrating their ability as TTA annihilator. More interesting, the acridine-based chromophore shows an excellent TTA yield that overcomes the one of some of best model systems. By correlating the experimental data and the quantum mechanical modeling of the investigated compound, we propose an alternative efficient pathway for the generation of the upconverted emissive states involving the peculiar high-energy triplet levels of the dye, thus suggesting a new development strategy for TTA annihilators based on the fine tuning of their high-energy excited states properties.Graphical abstract

In this paper we consider the question of sampling for spaces of entire functions of exponential type in several variables. The novelty resides in the growth condition we impose on the entire functions, that is, that their restriction to a hypersurface is square integrable with respect to a natural measure. The hypersurface we consider is the boundary bU of the Siegel upper half-space U and it is fundamental that bU can be identified with the Heisenberg group Hn. We consider entire functions in Cn+1 of exponential type with respect to the hypersurface bU whose restriction to bU are square integrable with respect to the Haar measure on Hn. For these functions we prove a version of the Whittaker–Kotelnikov–Shannon Theorem. Instrumental in our work are spaces of entire functions in Cn+1 of exponential type with respect to the hypersurface bU whose restrictions to bU belong to some homogeneous Sobolev space on Hn. For these spaces, using the group Fourier transform on Hn, we prove a Paley–Wiener type theorem and a Plancherel–Pólya type inequality.

Porous materials provide a versatile and robust platform for the development of optical materials with unique photonic and scintillating properties. The rigid and directional connectivity of the frameworks allows for the effective inclusion of a high density of organic cromophores avoiding aggregation issues, while the precise spatial arrangement governs the intermolecular interactions between emitting moieties. Highly porous emitting framework (PEF) nanoparticles comprising diphenylanthracene moieties were generated by Yamamoto-type Ullmann coupling reaction[1]. The nanoparticles display a surface area of 680 m2 g-1 and excellent emission properties with a photoluminescence quantum yield ~ 0.70 and decay time of 3.9 ns. The effective inclusion of a porphyrin sensitizer through the accessible porosity generates self-standing sensitized triplet-triplet annihilation (sTTA) upconverters with upconversion quantum yield as high as 0.15, a record value for solid-state materials. We propose nanocrystalline MOFs based on zirconium oxy-hydroxy clusters as fast scintillators. The MOFs nanocrystals with diphenylanthracene ligands display photoluminescence quantum yield up to 0.64 ± 0.09 and high radioluminescence and scintillation under high-energy excitations. The encapsulation of nanocrystals with 50 nm size generates innovative composite fast scintillators with high light yield and fast time response and an ultrafast scintillation rise time of ~ 50 ps[2]. The co-assembly of two conjugated luminescent ligands with complementary absorption and emission properties in Zr-MOFs shows effective non-radiative energy transfer, allowing for fast exciton diffusion and fast emission with large Stokes shift (~ 6000 cm-1) which inhibites re-absorption processes. Notably, the MOF inclusion in a continuous polymeric matrix provides enhanced scintillating properties compared with the homo-ligand nanocrystals[3]. [1] Advanced Materials, 2019, 31, 1903309. [2] Nature Photonics, 2021,15, 393-400. [3] Nature Communications, ASAP.

The photon upconversion based on sensitized triplet-triplet annihilation (sTTA-UC) is a spin-flip mechanism exploited to recover the energy stored on dark triplet states in conjugated systems. In this process, a high-energy fluorescent singlet is created through the collision and fusion of two low-energy triplets belonging to different diffusing molecules. Its high yield in solution under low excitation intensity and noncoherent light highlighted the huge potential of sTTA-UC to provide a breakthrough in solar technologies. However, its diffusion-limited nature restrains its efficiency in the solid state. To overcome this issue, we propose a single-molecule system that is able to host simultaneously more than one triplet, thus enabling a diffusion-free intramolecular TTA. We obtain the first direct demonstration of intramolecular triplet fusion by tailored photoluminescence spectroscopy experiments, thus opening the way to realize a new family of single-molecule upconverters with huge potential in solar and lighting technologies by accessing the natural triplets' energy reservoir.

The conversion of low-energy photons into radiation of higher energy is useful for bioimaging, 3D displays and other applications. In particular, upconversion of the infrared portion of the solar spectrum, which is typically not absorbed by the light-harvesting materials used in solar technologies, allows additional photons to be harnessed and boosts the efficiency of photovoltaic and photocatalytic devices. Therefore, low power photon upconversion of non-coherent light based on sensitized triplet-triplet annihilation (sTTA) has been recently recognized as a potential viable approach towards enhancing the efficiency of sunlight-powered devices through sub-bandgap photon harvesting. The sTTA permits the conversion of light into radiation of higher energy involving a sequence of photophysical processes between two moieties, respectively a light harvester/triplet sensitizer and an annihilator/emitter. High up-conversion yields under solar irradiance can be observed in low viscosity solutions of dyes, but in solid materials, which are better suited for integration in devices, the process is usually less efficient. The ability to control triplet excitons in the solid state is therefore crucial to obtain high performance solid upconverters. In this chapter, we will discuss the results obtained in several systems, such as dye-doped polymers/nanoparticles, amorphous/crystalline supramolecular structures and many others, highlighting the materials design guidelines to obtain efficient upconverters at the solid state that can match the strict requirements of solar technologies.

Abstract The Chinese Panorpa species without anal horn are normally assigned to the Panorpa davidi group. Here, we taxonomically revise the P. davidi group, which currently includes 17 known species and four new species: P. gaokaii sp. nov., P. huayuani sp. nov., P. uncinata sp. nov. and P. yaoluopingensis sp. nov. Panorpa shanyangensis Chou & Wang, 1981 and P. sexspinosa zhongnanensis Chou & Ran, 1981 are treated as junior synonyms of P. sexspinosa Cheng, 1949. We describe for the first time the male of P. stigmosa Zhou, 2006, and the females of P. curva Carpenter, 1938, P. davidi Navás, 1908, P. difficilis Carpenter, 1938, P. fructa Cheng, 1949, and P. jinchuana Hua, Sun & Li, 2001. A key to species of the group is provided. Phylogenetic analyses of maximum parsimony and maximum likelihood based on 79 morphological characters show that the newly defined P. davidi group is a well-supported monophyletic group and is sister to the genus Cerapanorpa Gao, Ma & Hua, 2016.

Little is known about the outcome predictors in peripheral neuropathy (PN). This prospective observational study aimed to identify possible factors predicting the functional abilities in older patients with PN undergoing motor rehabilitation. Data were collected in 80 PN patients, aged over 65 years, performing a standard inpatient motor rehabilitation program. The total Functional Independence Measure (FIM) score after rehabilitation, as well as efficiency and effectiveness in total-FIM, were the outcome measures. Backward multiple regression analyses identified the predictors of functional status. At the end of rehabilitation, total-FIM score was 102.66 ± 10.75, efficiency in total-FIM 0.64 ± 0.29 and effectiveness in total-FIM 48.81 ± 15.35%. Katz index at admission was a predictor of the final total-FIM score (beta 0.46, p

The sensitization of scintillation in polymeric composites based on fluorescent nanocomplexes. The archive contains 5 text files (including this annotation.txt) and one pdf file (ESI of the paper): 1. Annotation.txt (this file) 2. Nanomat_Scint_Sensitization_figure 2_Absorption_PL_TRPL _ energy transfer yield rate_Au8 superstructures and rhodamine 6G.TXT 3. Nanomat_Scint_Sensitization_figure 3_ RL spectra of the composite series as function of the emitter Rh6G concentration.txt 4. README Nanomat_scint.txt- where 2,3 files are described 5. nanomaterials-ESI.zip In this paper, the sensitization of scintillation was investigated in crosslinked polymeric composite materials loaded with luminescent gold clusters aggregates acting as sensitizers, and with rhodamine 6G as emitting dye. The findings enabled to give an expression of the sensitization efficacy as a function of the characteristic parameters of the employed luminescent systems and offer a guideline for the realization of composite materials with maximized sensitization effect. The name of the individual files is a short description of the content that has been explained with details in README.txt. All files are collected in one directory. The file 'README Nanomat_scint.txt' contains short description of the individual files.

In the last 15 years, the attention dedicated to organic conjugated systems experienced outstanding growth because of the renewed interest in mechanisms involving triplet states such as singlet fission, thermally activated delayed fluorescence, and intersystem crossing enhanced phosphorescence. Photon upconversion via sensitized triplet–triplet annihilation ( sTTA) enables the conversion of low-energy photons into high-energy ones, and it has been proposed in multicomponent systems as an efficient managing strategy of non-coherent photons. This mechanism exploits the annihilation of two optically dark triplet states of emitter moieties to produce high-energy photons. The annihilating triplets are sensitized through Dexter energy transfer by a light-harvester, typically a conjugated molecule or a nanocrystal, so sTTA upconversion is usually performed in bi-component systems. The high yield observed at low excitation intensities stimulated thriving research in the field, leading to the development of a large family of fully organic and hybrid sTTA multicomponent upconverters. Here, we compare the evolution of these two families of systems with respect to the sTTA upconversion main figures of merit, highlighting the strengths and weaknesses of both approaches, according to the results reported in the literature. The data presented are also discussed in the perspective of future developments in the field, pointing out the challenges that are still to be faced for the technological use of the sTTA upconversion process.

In this work we study what we call Siegel--dissipative vector of commuting operators $(A_1,\ldots, A_{d+1})$ on a Hilbert space $\mathcal H$ and we obtain a von Neumann type inequality which involves the Drury--Arveson space $DA$ on the Siegel upper half-space $\mathcal U$. The operator $A_{d+1}$ is allowed to be unbounded and it is the infinitesimal generator of a contraction semigroup $\{e^{-i\tau A_{d+1}}\}_{\tau, Comment: 17 pages. Typos were fixed and the references updated

Rotors, motors and switches in the solid state find a favorable playground in porous materials, such as Metal Organic Frameworks (MOFs) and Porous Aromatic Frameworks (PAFs), thanks to their large free volume, which allows for fast dynamics. We fabricated MOFs and PAFs with reorientable linkers and benchmark mobility also at very low temperature, to reduce the energy demand for motion-activation and light stimulus-response.[1] A fast molecular rotor in a Zn-MOF endowed with continuous, unidirectional hyperfast rotation with energy barrier of 6.2 cal/mol and high frequency persistent for several turns is achieved (Figure 1). Ligh responsive porous switchable frameworks took advantage of quantitative photoisomerization in the solid state and porosity of the framework to modulate the gas adsorption in response to light.[2] MOF nanocrystals comprising high-Z linking nodes interacting with the ionizing radiation, arranged in an orderly fashion at a nanometric distance from ligand emitters showed ultrafast sensitization of the ligand fluorescence, thus supporting the development of new engineered scintillators.[3] References [1] A. Comotti, P. Sozzani et al. Nat. Chem. 12 (2020) 845; [2] A. Comotti, B. Feringa, et al. Nature Chem. 12 (2020) 595; [3] A. Comotti, A. Vedda, A. Monguzzi, et al. Nature Photonics (2021), https://doi.org/10.1038/s41566-021-00769-z. Financial support from the Italian Ministry of University and Research (MIUR) through the grant ‘Dipartimenti di Eccellenza-2017 Materials For Energy’ is acknowledged. This research was funded by the PRIN-2015CTEBBA-003.

The robotic manipulation of deformable linear objects (DLOs) such as cables is currently a challenge. In this work, we propose a set of skills based on data from tactile sensors mounted on the end effector fingertips to allow the robot to optimally grasp a DLO and follow its contour. These skills are applied to perform a wiring operation.

The interest in collaborative robotics applications keeps increasing with the advancing of the years. Such growth is due to the robot's flexibility in the production line and to the interactions that may happen with the human partner. However, human-robot collaboration is far from being adopted in practice, especially for complex industrial applications such as assembly tasks. This work formalises an architecture that models human and robot workflows and synchronises their activities, spots errors during the human task execution, and notifies the operator that something unexpected happened. The system has then been tested in an industrial collaborative assembly operation.

In this work we explore the theme of $L^p$-boundedness of Bergman projections of domains that can be covered, in the sense of ramified coverings, by "nice" domains (e.g. strictly pseudoconvex domains with real analytic boundary). In particular, we focus on two-dimensional normal ramified coverings whose covering group is a finite unitary reflection group. In an infinite family of examples we are able to prove $L^p$-boundedness of the Bergman projection for every $p\in(1,\infty)$., 24 pages