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The removal of radioactive aqueous iodine is critical to the minimization of environmental impacts from nuclear energy production; however, its rapid and efficient removal at low-concentration level is still challenging. Herein, 2 nm metal–organic polyhedra (MOP) with a high binding affinity towards iodine are supramolecularly complexed with hydrophilic telechelic polymers and robust hybrid hydrogels with controlled hierarchical porosities can be obtained. The topologies of macromolecular ligands and the polymer/MOP concentrations are varied to elucidate the phase diagrams for hydrogel formation. The gels' meso-channel sizes and the distribution of hierarchical pores can be effectively regulated by varying the polymers' end groups and topologies. The meso-channels with optimized sizes favor the rapid diffusion of iodine while the homogenous distribution of MOP units maximizes the accessible area of MOP micropores, which cooperatively contributes to the high iodine capture efficiency. The MOP hydrogel demonstrated high absorption rate (2.336 g g−1 h−1) towards iodine molecules, surpassing most of the as-reported adsorbents. The work not only provides solutions for the robust formation of MOP-based hydrogels, but also paves new avenues for the effective treatment of low dose aqueous radioactive iodine. [ABSTRACT FROM AUTHOR]

The high‐speed impact‐resistanct materials are of great significance while their development is hindered by the intrinsic tradeoff between mechanical strength and energy dissipation capability. Herein, the new chemical system of molecular granular material (MGM) is developed for the design of impact‐resistant materials from the supramolecular complexation of sub‐nm molecular clusters (MCs) and hyper‐branched polyelectrolytes. Their hierarchical aggregation provides the origin of the decoupling of mechanical strengths and structural relaxation dynamics. The MCs' intrinsic fast dynamics afford excellent high‐speed impact‐resistance, up to 5600 s−1 impact in a typical split‐Hopkinson pressure bar test while only tiny boundary cracks can be observed even under 7200 s−1 impact. The high loadings of MCs and their hierarchical aggregates provide high‐density sacrificial bonding for the effective dissipation of the impact energy, enabling the protection of fragile devices from the direct impact of over 200 m s−1 bullet. Moreover, the MGMs can be conveniently processed into protective coatings or films with promising recyclability due to the supramolecular interaction feature. The research not only reveals the unique relaxation dynamics and mechanical properties of MGMs in comparison with polymers and colloids, but also develops new chemical systems for the fabrication of high‐speed impact‐resistant materials. [ABSTRACT FROM AUTHOR]

Cost‐effective, non‐fluorinated polymer proton exchange membranes (PEMs) are highly desirable in emerging hydrogen fuel cells (FCs) technology; however, their low proton conductivities and poor chemical and dimension stabilities hinder their further development as alternatives to commercial Nafion®. Here, we report the inorganic‐organic hybridization strategy by facilely complexing commercial polymers, polyvinyl butyral (PVB), with inorganic molecular nanoparticles, H3PW12O40 (PW) via supramolecular interaction. The strong affinity among them endows the obtained nanocomposites amphiphilicity and further lead to phase separation for bi‐continuous structures with both inter‐connected proton transportation channels and robust polymer scaffold, enabling high proton conductivities, mechanical/dimension stability and barrier performance, and the H2/O2 FCs equipped with the composite PEM show promising power densities and long‐term stability. Interestingly, the hybrid PEM can be fabricated continuously in large scale at challenging ~10 μm thickness via typical tape casting technique originated from their facile complexing strategy and the hybrids' excellent mechanical properties. This work not only provides potential material systems for commercial PEMs, but also raises interest for the research on hybrid composites for PEMs. [ABSTRACT FROM AUTHOR]

Coordinative supramolecular cages with adjustable cavities have found extensive applications in various fields, but the cavity modification strategies for multi‐functional structures are still challenging. Here, we present a tension‐driven self‐expansion strategy for construction of multi‐cavity cages with high structural complexity. Under the regulation of strain‐induced capping ligands, unprecedented heteromorphosis triple‐cavity cages S2/S4 were obtained based on a metallo‐organic ligand (MOL) scaffold. The heteromorphosis cages exhibited significant higher cavity diversity than the homomorphous double‐cavity cages S1/S3; all of the cages were thoroughly characterized through various analytical techniques including (1D and 2D) NMR, ESI‐MS, TWIM‐MS, AFM, and SAXS analyses. Furthermore, the encapsulation of porphyrin in the cavities of these multi‐cavity cages were investigated. This research opens up new possibilities for the architecture of heteromorphosis supramolecular cages via precisely controlled "scaffold‐capping" assembly with preorganized ligands, which could have potential applications in the development of multifunctional structures with higher complexity. [ABSTRACT FROM AUTHOR]

This Review addresses the use of X‐ray and neutron scattering as well as X‐ray absorption to describe how inorganic nanostructured materials assemble, evolve, and function in solution. We first provide an overview of techniques and instrumentation (both large user facilities and benchtop). We review recent studies of soluble inorganic nanostructure assembly, covering the disciplines of materials synthesis, processes in nature, nuclear materials, and the widely applicable fundamental processes of hydrophobic interactions and ion pairing. Reviewed studies cover size regimes and length scales ranging from sub‐Ångström (coordination chemistry and ion pairing) to several nanometers (molecular clusters, i.e. polyoxometalates, polyoxocations, and metal‐organic polyhedra), to the mesoscale (supramolecular assembly processes). Reviewed studies predominantly exploit 1) SAXS/WAXS/SANS (small‐ and wide‐angle X‐ray or neutron scattering), 2) PDF (pair‐distribution function analysis of X‐ray total scattering), and 3) XANES and EXAFS (X‐ray absorption near‐edge structure and extended X‐ray absorption fine structure, respectively). While the scattering techniques provide structural information, X‐ray absorption yields the oxidation state in addition to the local coordination. Our goal for this Review is to provide information and inspiration for the inorganic/materials science communities that may benefit from elucidating the role of solution speciation in natural and synthetic processes. [ABSTRACT FROM AUTHOR]

Commercial proton exchange membranes (PEMs) have high requirements for environmental humidity, which significantly narrows the applications of PEM-assembled fuel cells and raises the costs of humidity maintenance. Herein, polyvinyl alcohol and a nanosized metal oxide cluster (MOC) are complexed with glycerol and boric acid for the fabrication of hybrid hydrogels. The formation of dynamic reversible bonds and multiple supramolecular interactions among the structural units contributes to the simultaneous achievement of appreciable mechanical strength and (re)processability. The as-formed enriched hydrogen bonding networks provide highways for fast proton conduction, while the solvent molecules can be tightly trapped by the gels' nano-confined cavities. The appreciable proton conductivity and excellent water retention capacity project the application of the gel at low humidity. EIS analysis demonstrates that the proton conductivity of the resultant gel can reach as high as 4.7 × 10−4 S cm−1 at 30% relative humidity. Upon further assembly into a single fuel cell, the working plots of the as-assembled devices show satisfactory maximal power density of 141 mW cm−2 under dry gas conditions. Our design protocol opens up a new avenue for the fabrication of cluster-based gel PEMs applicable for use at low humidity. [ABSTRACT FROM AUTHOR]

Molecular granular materials (MGMs) are constructed with sub‐nanoscale molecular clusters (MCs) as the building units and they have recently been observed to possess enriched functionalities distinct from granular materials of colloid nanoparticles. Herein, the birth and recent research advances in MGMs are summarized with the topics covering the precise synthesis of MC assemblies with target topologies, the hierarchical relaxation dynamics and tuneable viscoelasticity, impact‐resistant capacity, and proton conductivity performance. The extremely small size of MC renders them two features: bulk diffusive dynamics with energy scale close to thermal fluctuation energy and the dominant volume fraction of surface structures. This finally leads to the hierarchical relaxation dynamics and broadly tuneable viscoelasticity of MGMs although the structural units are with small sizes and low Mw. Therefore, MGMs have been applied as impact resistant materials and proton conductors for the highly tuneable relaxation dynamics. [ABSTRACT FROM AUTHOR]

Fractal structures with self‐similarity are of fundamental importance in the fields of aesthetic, chemistry and mathematics. Here, by taking advantage of constructs the rational geometry‐directed precursor design, we report the construction of two fascinating Platonic solids, the Sierpiński tetrahedron ST‐T and the Sierpiński octahedron ST‐O, in which each possesses a fractal Sierpiński triangle on their independent faces. These two discrete complexes are formed in near‐quantitative yield from the multi‐component self‐assembly of truncated Sierpiński triangular kernel L1 with tribenzotriquinacene‐based hexatopic and anthracene‐based tetratopic terpyridine ligands (L3 and L4) in the presence of metal ions, respectively. The enhanced stabilities of the 3D discrete structures were investigated by gradient tandem mass spectrometry (gMS2). This work provides new constructs for the imitation of complex virus assemblies and for the molecular encapsulation of giant guest molecules. [ABSTRACT FROM AUTHOR]

This article, published in Angewandte Chemie, discusses the challenges and potential solutions in the synthesis of miktoarm star polymers. The authors, Mingxin Zhang, Panchao Yin, and their colleagues, propose the use of metal-organic polyhedra with logarithmic ligand exchange dynamics as templates for the reversible sorting and hybridization of miktoarm star polymers. This approach opens up new possibilities for the design of sustainable polymers. The article also briefly mentions other research topics such as visible-light photoswitchable benzimidazole azo-arenes, enantioselective synthesis of arylglycines, electrochemical diacetoxylation of alkenes, and the control of structural properties in supported/bulk metal oxides through catalyst post-treatment. [Extracted from the article]

Three new monoterpenoid alkaloids, melomorines A-C (1-3), along with melohemsine B (4), were isolated from the 70% ethanol extract of the aerial parts of Melodinus morsei. Structural elucidation of all the compounds was performed on the basis of spectral data. All the compounds were tested in vitro for cytotoxic activities. As a result, alkaloids 1, 2, and 4 exhibited cytotoxicities against all the five tested tumor cell lines with IC50 value of less than 20 μM. [ABSTRACT FROM AUTHOR]

Keywords: Impact resistance; Molecular granular materials; Relaxation dynamics; Sub-nanoscale particle; Topological interaction EN Impact resistance Molecular granular materials Relaxation dynamics Sub-nanoscale particle Topological interaction 1 1 1 05/18/23 20230516 NES 230516 B Recent advances in b molecular granular materials (MGMs) which are assembled from molecular cluster (MC) units have been systematically reviewed from both molecular mechanisms and application aspects. Impact resistance, Molecular granular materials, Relaxation dynamics, Sub-nanoscale particle, Topological interaction The hierarchical structural dynamics endow MGMs with unique mechanical properties including tunable viscoelasticity and impact-resistant capacity. [Extracted from the article]

Objective To evaluate narcotic drugs utilization in our hospital in 2008~2013 and developing trend, so as to provide references for the narcotics reasonable application. Methods We collected the related data of narcotic using in clinical departments in 2008~2013 and the number of outpatient and hospitalization, and analyzed the data with statistical software. Results The increase of narcotic drugs consumption of in our hospital is out of the increase of the number of patients. Especially consumption of strong oral opioid analgesics increased year by year, the consumption of morphine tablets is less. Consumption of Dezocine and Butorphanol grow rapidly, while consumption of Fentanyl patch fluctuated largely. Consumption of weak opioid analgesics increased year by year as a whole. Consumption of sedative hypnotics had small growth. Conclusion There is misunderstanding in strong opioid painkillers in treatment of cancer pain, the spread of the cancer pain treatment remains to be further strengthened [ABSTRACT FROM AUTHOR]

A novel photoresponsive, water‐soluble supramolecular dendronized polymer (SDP) is prepared through a γ ‐cyclodextrin (γ ‐CD)‐coumarin host–guest interaction. The supramolecular formation, photoresponsive process, and fluorescence properties are investigated by nuclear magnetic resonance (NMR) techniques and spectrometric measurements. Upon different‐wavelength light irradiation, this supramolecular polymer undergoes noncovalent polymer and covalent polymer conversion due to coumarin cycloaddition and cleavage reactions. In addition, SDP for bioimaging in Michigan Cancer Foundation‐7 (MCF‐7) cells is performed and results show that the obtained SDP has good biocompatibility and is lysosome‐targetable. This research enriches the field of supramolecular dendrimers and the photo‐stimulation response material may have application prospects in organelle‐targeting applications. A novel photoresponsive water soluble supramolecular dendronized polymer (SDP) is prepared through a γ ‐cyclodextrin (γ ‐CD)‐coumarin host‐guest interaction. The supramolecular formation, photoresponsive process, and fluorescence properties are investigated by NMR techniques and spectrometric measurements. In addition, this SDP is used for bioimaging in MCF‐7 cells and results show that the obtained SDP is lysosome‐targetable. [ABSTRACT FROM AUTHOR]

The precise synthesis of miktoarm star polymers (MSPs) remains one of the great challenges in synthetic chemistry due to the difficulty in locating appropriate structural templates and polymer grafting/growing strategies with high selectivity and efficiency. Herein, ≈2 nm metal-organic polyhedra (MOPs), constructed from the coordination of isophthalic acid (IPA) and Cu 2+ , are applied as templates for the precise synthesis of 24-arm MSPs for their unique logarithmic ligand-exchange dynamics. Six different polymers are prepared with IPA as an end group and they further coordinated with Cu 2+ to afford the corresponding 24-arm star homo-polymers. MSPs can be obtained by mixing targeted homo-arm star polymers in solutions upon thermal annealing. The compositions of MSPs can be facilely and precisely tuned by the recipe of the star polymer mixtures used. Interestingly, the obtained MSPs can be sorted into homo-arm star polymers through a typical solvent extraction procedure. The hybridization and sorting process can be reversibly conducted through the cycle of thermal annealing and solvent treatment. The complex coordination framework not only opens new avenues for the facile and precise synthesis of MSPs and MOPs with hybrid functionalities, but also provides the capability to design sustainable polymer systems., (© 2023 Wiley-VCH GmbH.)

In expanding our research activities of superlattice engineering, designing new giant molecules is the necessary first step. One attempt is to use inorganic transition metal clusters as building blocks. Efficient functionalization of chemically precise transition metal clusters, however, remains a great challenge to material scientists. Herein, we report an efficient thiol-Michael addition approach for the modifications of cyclic titanium-oxo cluster (CTOC). Several advantages, including high efficiency, mild reaction condition, capability of complete addition, high atom economy, as well as high functional group tolerance were demonstrated. This approach can afford high yields of fully functionalized CTOCs, which provides a powerful platform for achieving versatile functionalization of precise transition metal clusters and further applications., (© 2023 Wiley-VCH GmbH.)