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Osmotic power generation has emerged as an advanced technology toward water-energy nexus to tackle global water pollution. It provides a sustainable use of salinity gradient from water resources yet encounters major obstacles caused by pressure-retarded osmosis (PRO) membrane fouling. Although membranes with good antifouling properties are widely studied, their antifouling functions are readily lost when scratches or detachments occur through physical damage during operation and chemical degradation by water and corrosive foulants. Consequently, it is important to develop antifouling membranes with autonomous self-healing capabilities. Herein, self-healable functionalized poly(ether sulfone) (PES) antifouling membranes have been fabricated via the sequential conjugation of the zwitterionic random copolymer [poly(1-(1-(1-adamantylcarbonyloxy)methyl)-3-vinylimidazolium bromide-co-1-(3-sulfopropyl)-3-vinylimidazolium-co-vinylamine)] (P(ADVI-co-SBVI-co-VA), abbreviated as PASV copolymer) and linear cyclodextrin polymer (LPCD) on polydopamine-preactivated PES supports. The self-healing behaviors rely on the judiciously designed "button-and-buttonhole" supramolecular network. Specifically, β-cyclodextrins in LPCD and adamantines in PASV act as "buttonholes" and "buttons", respectively. Under physical and chemical damages, the β-cyclodextrin "buttonhole" may sacrificially detach from the adamantine "button" of PASV but then recap another adamantine to restore the protective function. The antifouling and self-healing traits of as-functionalized PES-g-PASV-LPCD membranes were demonstrated by the superior antiprotein behaviors and improved antimicrobial performances on both nonaged and aged samples. In the PRO process, the modified membranes were effective in mitigating organic fouling and exhibited higher power density (79% of the initial value) than the nonmodified ones (47% of the initial value) in municipal wastewater testing. The strategy for engineering inherently healable and antifouling membranes paves a new pathway for the development of sustainable membranes for osmotic power production.

The implementation of photocatalysts for controlled/living radical polymerization upon visible light harvesting has emerged as a robust and powerful technique for the user-friendly synthesis of well-structured polymers with composition, spatiotemporal, and sequence control. Nevertheless, the incompatibility of present synthetic protocols with environmentally benign media, such as water, still poses a detrimental threat to their practical applications. In this article, the adoption of hPGM-ZnTPP hollow microspheres with pH sensitivity and excellent dispersibility in various reaction media, which are firmly immobilized yet accessible catalytic metalloporphyrin components as heterogeneous photocatalysts for the photoinduced electron/energy transfer-reversible addition–fragmentation chain transfer (PET-RAFT) polymerization, was demonstrated. Modulation of solution pH affected the performance of the catalysts, with the faster polymerization rate being observed in basic conditions rather than in acidic conditio...

In recent years, pressure retarded osmosis (PRO) has drawn considerable attention due to its feasibility of harvesting clean and sustainable osmotic power through a membrane process. When municipal wastewater is fed into this process, fouling in the porous substrate of the PRO membrane is the major concern since it can hinder the membrane performance tremendously and lower the power generation. In this work, sulfonated hyperbranched polyglycerol (SHPG) polymers with a dendritic architecture have been molecularly designed and then grafted onto the surface of polydopamine (PDA) coated poly(ethersulfone) (PES) hollow fiber membranes. Comparing to the pristine PES membranes, the SHPG modified PRO membranes show significantly improved resistance to protein adhesion and bacterial attachment due to the high wettability of their ionic polymer brushes. In PRO tests under different hydraulic pressures, the SHPG-grafted membranes show a lower flux reduction and a higher flux recovery rate of 94% vs. 87% in comparison with the pristine PES membranes. Therefore, the osmotic power generation can be significantly sustained by modifying the PRO membranes with SHPG polymers. This work may provide a versatile approach and useful insights for the design of membranes with antifouling properties in the molecular level.

Biomacromolecules, including matrix proteins, are important in shell-mineralization processes, such as inducing crystal nucleation, regulating crystal polymorphism and morphology. In this study, we identified the novel matrix protein hc-upsalin from the freshwater pearl mussel Hyriopsis cumingii, associated with its significantly high similarity to the known matrix protein upsalin in the freshwater mussel Unio pictorum. The full-length cDNA of hc-upsalin encodes 119 amino acids, including a potential signal peptide of 17 residues. The mature protein is characterized by high proportions of Gly (13.7%), Cys (11.8%), and Pro (11.8%), with a molecular weight of 11.4 kDa and a theoretical pI of 6.93. Hc-upsalin is specifically expressed in muscular tissues mostly in the mantle, with positive signals detected in dorsal epithelial cells of the mantle by in situ hybridization, and decreased expression of hc-upsalin leaded to random accumulation of tablet, suggesting its involvement in shell nacreous-layer biomineralization. Furthermore, hc-upsalin gene-expression patterns during pearl biomineralization indicated a potential role in the process of pearl nacreous-layer calcification.

Hybrid nanorattles by spatial inclusion catalytic nanocores into hollow shells as nanoreactors have stimulated tremendous interests in advanced technologies for the sustainable production and conversion of energy. However, the nanoshells fabricated by inorganic compositions usually lack of desirable elasticity, permeability, and responsiveness to meet the requirement of increasingly complex and sophisticated catalytic systems. In this study, we describe a new strategy to construct a smart hybrid nanoreactor with an ultrathin and flexible polymer shell based on in situ thiol–ene photopolymerization. The morphological transitions in the hyperbranched poly(glycerol-co-N,N-diallyl glycidyl amine) (HPGD) shells of the Pt@hHPGD nanorattles result in the precise tuning of efficient mass transfer to encapsulated Pt nanocores in response to external stimuli. The fabricated Pt@hHPGD yolk–shell nanoreactors exhibited highly enhanced activity, longevity, and recyclability in catalyzing the hydrogenation of p-nitrophe...

Polycarbonate/poly(butylene terephthalate) (PC/PBT) blends exhibit wide applications in many fields. However, the blends usually exhibit poor mechanical and thermal properties because of the transesterification reaction occurred between molecules of the blend components. In this work, a small quantity of carbon nanotubes (CNTs) was introduced into the PC/PBT blend to prepare the ternary blend composites with balanced macroscopic properties. The dispersion of CNTs in the blend composites and the microstructural changes induced by CNTs were comparatively investigated. The results demonstrated that CNTs exhibit relatively homogeneous dispersion in the blend composites. Specifically, at relatively high content, CNTs form the percolated network structure. The crystallization ability of the PBT component is greatly enhanced with the aid of the nucleation effect of CNTs. Mechanical property measurements showed that CNTs exhibit strengthening and toughening effects on the PC/PBT blend, especially incorporating 2 wt% CNTs leads to the dramatic increase of tensile ductility. Further results showed that the blend composites also exhibit excellent antistatic performance. It is believed that the simultaneously improved fracture toughness and antistatic performance endow the blend composites with more potential applications.

Small quantities of maleic anhydride grafted styrene-ethylene-butylene-styrene (SEBS-g-MAH) copolymer and carbon nanotubes (CNTs) were introduced into polycarbonate (PC)/poly(butylene terephthalate) (PBT) blends. The results demonstrated that simultaneously adding SEBS-g-MAH and CNTs greatly enhanced the fracture toughness of the samples and the impact strength increased with increasing CNT content. The morphologies, the dispersion of CNTs, the relaxation behaviors and the crystallization behaviors of samples were systematically investigated. SEBS-g-MAH formed the dispersed particles in the system. The particle diameter was decreased in the blend composites. CNTs exhibited homogeneous dispersion in the blend composites and they also formed a percolated network structure at relatively high content. The transesterification between PC and PBT components was suppressed by SEBS-g-MAH, and the crystallization ability of the PBT component was greatly enhanced. The toughening mechanisms were mainly related to the suppressed transesterification, the decreased elastomer particle size, and the formation of a CNT network structure.

Photoinduced electron/energy transfer-reversible addition–fragmentation chain transfer (PET-RAFT) polymerization has become a powerful and eco-friendly toolkit to create well-defined macromolecular buildups while exhibiting composition, sequence and spatiotemporal control. Although PET-RAFT polymerization is generally much more convenient than living ionic polymerization, it is still a great challenge to regulate the polymerization upon multiple external stimuli and to simplify the procedures of post-polymerization purification. In this contribution, hHPGE-PFPPNRu nanocomposites were engineered as catalyst supports to firmly accommodate ruthenium–bipyridine complexes for heterogeneous catalysis of PET-RAFT polymerization. The manipulation of reaction temperature modulated the performance of the nanocatalysts, with a pronounced acceleration of the polymerization kinetics being identified at a temperature above the lower critical solution temperature (LCST) of poly(N-isopropylacrylamide) (PNIPAM) brushes compared to that below it. Consequently, the control of RAFT polymerization can be achieved upon the dual-stimuli of light and heat. Moreover, these nanocatalysts conferred radical polymerizations with myriad attractive features such as the adaptability of diverse monomer formulations and reaction media, exquisite control over the molecular variables, oxygen tolerance, and catalyst doses in the ppm range. Owing to the robust mechanical nature of nanocomposites, the separation and reuse of the nanocatalysts were readily realized by rapid centrifugation, and they showed inappreciable catalyst leakage along with consistent catalytic performance even after multiple polymerization runs.

A new compound, namely, [Zn(L)2]n (1) was obtained by the reaction of 2-methyl-4-(4H-1,2,4-triazol-4-yl) benzoic acid (HL) with ZnSO4&middot, 7H2O, and the compound was characterized by single-crystal X-ray diffraction, infrared spectroscopy, elemental analysis, powder X-ray diffraction (PXRD), and thermogravimetric analysis. The linear HL ligands were deprotonated to be L&minus, anions and act as two-connectors to link Zn2+ to form a two-dimensional (2D) lay structure with (4, 4) topology. The large vacancy of 2D framework allows another layer structure to interpenetrate, resulting in the formation of 2D + 2D &rarr, 2D parallel interpenetration in 1. The weak interactions, such as hydrogen bonding and &pi, &ndash, &pi, stacking interactions, connect the adjacent 2D layers into a three-dimensional (3D) coordination polymer. The solid-state UV-visible spectroscopy and luminescent property have also been studied.

Individual layer thickness dependent mechanical properties of amorphous/amorphous NiNb/ZrCuNiAlSi nanolaminates were evaluated via nanoindentation testing. While hardness only slightly increases, the magnitude of pile-up around residual indentation was estimated to be effectively decreased at reduced individual layer thickness. By ruling out the effect of the ratio of effective elastic modulus over yield strength of the multilayers, the variation trend of pile-up may attribute to the high capacity of work hardening derived from decreasing the layer thickness. The mechanism behind the enhanced work hardening of the amorphous composites was proposed, and may path a new way to fabricate metallic glasses with improved plasticity.

Increasing exposure chances of humans to low-energy gamma-rays occur with the rapid application expansion of nuclear technology, which tend to induce carcinogenic and mutagenic effects on living bodies, and then need to be protected from. PbWO4 has excellent gamma-rays attenuating ability while Pb displays a weak shielding property of low-energy gamma-rays from 40 keV to 88 keV. Here, crystal defect engineering with Ce doping is applied to fabricate the crystal structure of PbWO4 for tailoring its low-energy gamma-rays shielding property. Characterization with XRD, Raman, XPS, XRF, SEM and TEM techniques indicates cerium ions have been introduced into the lattice of PbWO4 crystals during the doping process. In addition, Ce doping amount plays key roles in tuning the crystal defects in PbWO4 including ion substitution, charge compensation and structural deformation. Importantly, PbWO4 doped with 10 mol% Ce displays an optimal mass attenuation coefficient (2.61 cm2/g) to 59.5 keV gamma-rays and shows a 39% increase ratio to the PbWO4 without doping. In addition, typically anisotropic PbWO4 crystals are found at 40 mol% Ce doping amount, which give its potential versatility. This work provides a solution to make up for PbWO4 to shield low-energy gamma-rays that could further promote its application in personal protection, such as clothing.

The capability to spatiotemporally regulate polymerization kinetics in response to dual external stimuli of light and magnetism offers exciting pathways to precisely manipulate polymer composition and sequence. Herein, we report a strategy that adopts snowman-shaped Fe3O4@aSiO2-click-ZnPTPP Janus nanocomposites with a high magnetization value (12.9 emu g−1) and stably confined but accessible catalytic metalloporphyrin moieties as the nanocatalysts for photo-induced electron transfer reversible addition–fragmentation chain transfer (PET-RAFT) polymerization. This method enables the synthesis of diverse polymeric structures from a large range of monomers using ultralow concentrations of nanocatalysts (less than 10 ppm) with simple modulation of light and magnetism. In addition, the nanocatalysts are found to be oxygen-tolerant, and they exhibit non-agglomeration during polymerization. Finally, repeated regeneration of the used nanocatalysts by magnetic extraction or facile centrifugation effectively reduces or even eliminates the contamination and/or decomposition on the final polymer products.

C20H18CoN12O2, monoclinic, C2/c (no. 15), a = 17.6924(15) Å, b = 11.3253(10) Å, c = 12.8536(11) Å, β = 128.029(10)° V = 2028.7(3) Å3, Z = 4, R gt(F) = 0.0258, wR ref(F 2) = 0.0890, T = 296(2) K.

Four new metal&ndash, organic coordination polymers [Cu(L)(mpa)]&middot, 3H2O (1), [Co(L)(mpa)]&middot, H2O (2), [Zn(L)(mpa)]&middot, H2O (3), and [Cd(L)(mpa)(H2O)]&middot, H2O (4) were synthesized by reactions of the corresponding metal(II) salts based on mixed ligands of 1,4-di(1H-imidazol-4-yl)benzene (L) and 4-methylphthalic acid (H2mpa), respectively. The structures of the complexes were characterized by elemental analysis, FT-IR spectroscopy, and single-crystal X-ray diffraction. Compound 1 exhibits a binodal 4-connected three dimensional (3D) architecture with (65&middot, 8)-CdSO4 topology, while complexes 2 and 3 are isostructural and have two-dimensional (2D) layer structure with (4, 4) sql topology based on the binuclear metal subunits. Complex 4 has the same 2D layer structure with (4, 4) sql topology as complexes 2 and 3, but the inclined interpenetration of parallel sets of layers result in the formation with 2D + 2D &rarr, 3D framework. The activated sample 1 shows selective CO2 uptake over N2. The photoluminiscent properties together with quantum yield (QY) and luminescence lifetime are also investigated for complexes 3 and 4 in the solid state at room temperature.