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The synergetic binary phosphazene/triethylborane (TEB) system is highly active and selective towards the ring‐opening alternating copolymerization of CO2 with different epoxides to prepare diverse CO2‐based polycarbonates (CO2‐PCs). In their Research Article (e202111197), Shaofeng Liu, Zhibo Li, and co‐workers report that this metal‐free organocatalyst can efficiently copolymerize CO2 with cyclohexene oxide under ambient conditions (1 atm pressure and room temperature), which is an environmentally friendly and more carbon‐balanced way toward CO2 utilization. [ABSTRACT FROM AUTHOR]

Keywords: ambient conditions; CO2 utilization; organocatalysts; polycarbonates; sustainable polymers EN ambient conditions CO2 utilization organocatalysts polycarbonates sustainable polymers 1 1 1 01/18/22 20220121 NES 220121 B Das synergetische b binäre Phosphazen/TEB-System ist hochaktiv und selektiv für die alternierende Ringöffnungs-Copolymerisation von CO SB 2 sb mit verschiedenen Epoxiden zur Herstellung verschiedener CO SB 2 sb -basierter Polycarbonate (CO SB 2 sb -PCs). Innenrücktitelbild: Synthesis of Diverse Polycarbonates by Organocatalytic Copolymerization of CO2 and Epoxides: From High Pressure and Temperature to Ambient Conditions (Angew. Ambient conditions, CO2 utilization, organocatalysts, polycarbonates, sustainable polymers. [Extracted from the article]

The coassembly of poly(ethylene glycol)-b-poly(glutamatesodium) copolymer (PEG113-PGlu100) with cationicgemini surfactants alkanediyl-α,ω-bis-(dodecyldimethylammoniumbromide) [C12H25(CH3)2N(CH2)SN(CH3)2C12H25]Br2(designated asC12CSC12Br2, S= 3, 6, and 12) have been studied by isothermaltitration microcalorimetry, cryogenic transmission electron microscopy,circular dichroism, small-angle X-ray scattering, zeta potential,and size measurement. It has been shown that the electrostatic interactionof C12CSC12Br2with the anionic carboxylate groups of PEG113-PGlu100leads to complexation, and the C12CSC12Br2/PEG113-PGlu100complexes are soluble even at the electroneutral point.The complexes display the feature of superamphiphiles and assembleinto ordered nanosheets with a sandwich-like packing. The gemini moleculeswhich were already bound with PGlu chains associate through hydrophobicinteraction and constitute the middle part of the nanosheets, whereasthe top and bottom of the nanosheets are hydrophilic PEG chains. Thesize and morphology of the nanosheets are affected by the spacer lengthof the gemini surfactants. The average sizes of the aggregates atthe electroneutral point are 81, 68, and 90 nm for C12C3C12Br2/PEG113-PGlu100, C12C6C12Br2/PEG113-PGlu100, and C12C12C12Br2/PEG113-PGlu100, respectively.Both C12C3C12Br2/PEG113-PGlu100and C12C12C12Br2/PEG113-PGlu100mainlygenerate hexagonal nanosheets, while the C12C6C12Br2/PEG113-PGlu100system only induces round nanosheets. [ABSTRACT FROM AUTHOR]

Two solution-processableacceptor–donor–acceptor(A-D-A) structured organic molecules with bithienyl-substituted benzodithiophene(BDTT) as central and donor unit, indenedione (ID) as acceptor unitand end groups, and thiophene (T) or bithiophene (bT) as π-bridges,D1 and D2, are designed and synthesized for the application as donormaterials in organic solar cells (OSCs). Two corresponding moleculeswith alkoxy side chains on BDT, DO1, and DO2 are also synthesizedfor comparison. The four compounds possess broad absorption coveringthe wavelength range 450–740 nm and relatively lower HOMO energylevels from −5.16 to about −5.19 eV. D2 and DO2 withbithiophene π-bridges demonstrate stronger absorbance and higherhole mobilities than the compounds with thiophene π-bridges.The power conversion efficiency (PCE) values of the OSCs based onthe organic compounds/PC70BM (1.5:1, w/w) are 6.75% forD2, 5.67% for D1, 5.11% for DO2, and 4.15% for DO1. The results indicatethat the molecules with thienyl conjugated side chains and bithiopheneπ-bridges show better photovoltaic performance. The PCE of theD2-based OSC are among the highest values in the OSCs based on thesolution-processed organic small molecules. [ABSTRACT FROM AUTHOR]

A series of new functional aminoacids were prepared in high yield via thiol–ene Michael additionbetween l-cysteine and monomethoxy oligo(ethylene glycol)(OEG) functionalized methacrylates (OEGxMA) and acrylate (OEGxA). These OEGylatedcysteine derivatives were converted into polymerizable N-carboxyanhydride (NCA) monomers using triphosgene. Subsequent ring-openingpolymerization (ROP) of these NCA monomers gave a series of OEGylatedpoly-l-cysteine (poly-EGxMA-Cor poly-EGxA-C) homopolypeptides. Dependingon the length of OEG side chains, poly-EGxMA-C and poly-EGxA-C polypeptides displayeddifferent solubility and secondary structure in water. More importantly,the obtained polypeptides can display reversible thermoresponsiveproperties in water when the xvalue is between 3and 5. The synthetic strategy represents a highly efficient methodto prepare nonionic functional polypeptides with tunable thermoresponsiveproperties. [ABSTRACT FROM AUTHOR]

Abstract: Diperylene bisimide bearing poly(ethylene glycol) chains (PEG-diPBI) were synthesized using click coupling reaction between mono-azido terminated PEG113 and bis-alkynyl functionalized diPBI. Then the PEG-diPBI self-assembled into micelles in water, which were characterized by cryo-TEM, UV–Vis spectrometry and fluorescence spectrometry. Furthermore, the PEG-diPBI was applied by continuous photolysis procedure, the result showed a broad absorption and very high efficiency of 1O2 generation (Φ Δ = 0.66). Moreover, the uptake of PEG-diPBI particles by human bladder carcinoma EJ cells was observed by confocal laser scanning microscopy. Also, phototoxicity experiment result was applied to PEG-diPBI, and gave the result that it is worth to investigate the properties of PEG-diPBI particles for photodynamic therapy. [Copyright &y& Elsevier]

A new type of DNA grafted polypeptide molecular brushwas synthesizedvia a combination of ring-opening polymerization (ROP) and click chemistry.This conjugation method provides an easy and efficient approach toobtain a hybrid DNA-grafted polypeptide molecular bottlebrush. Thestructure and assembly behaviors of this hybrid brush were investigatedusing electrophoresis, UV–vis spectroscopy, transmission electronmicroscopy (TEM), and atomic force microscopy (AFM). Hierarchicalsupramolecular assemblies can be obtained through hybridization oftwo kinds of polypeptide-g-DNA molecular bottlebrushescontaining complementary DNA side chains. We further demonstratedthat such polypeptide-g-DNA can be hybridized withds-DNA and DNA-grafted gold nanoparticles to form a supermolecularbottlebrush and hybrid bottlebrush, respectively. In addition, DNA-polypeptidehydrogel can be prepared by hybridization of polypeptide-g-DNA with a linker-ds-DNA, which contains the complementary “stickyends” to serve as cross-linkers. [ABSTRACT FROM AUTHOR]

The association behaviors of single-chain surfactantdodecyltrimethylammoniumbromide (DTAB) with double hydrophilic block co-polymers poly(ethyleneglycol)-b-poly(sodium glutamate) (PEG113–PGlu50or PEG113–PGlu100) were investigated using isothermal titration microcalorimetry,cryogenic transmission electron microscopy, circular dichroism, ζpotential, and particle size measurements. The electrostatic interactionbetween DTAB and the oppositely charged carboxylate groups of PEG–PGluinduces the formation of super-amphiphiles, which further self-assembleinto ordered aggregates. Dependent upon the charge ratios betweenDTAB and the glutamic acid residue of the co-polymer, the mixturesolutions can change from transparent to opalescent without precipitation.Dependent upon the chain length of the PGlu block, the mixture ofDTAB and PEG–PGlu diblocks can form two different aggregatesat their corresponding electroneutral point. Spherical and rod-likeaggregates are formed in the PEG113–PGlu50/DTAB mixture, while the vesicular aggregates are observed in thePEG113–PGlu100/DTAB mixture solution.Because the PEG113–PGlu100/DTAB super-amphiphilehas more hydrophobic components than that of the PEG113–PGlu50/DTAB super-amphiphile, the former prefersforming the ordered aggregates with higher curvature, such as sphericaland rod aggregates, but the latter prefers forming vesicular aggregateswith lower curvature. [ABSTRACT FROM AUTHOR]

Abstract: A well-defined polysilsesquioxane with reactive Si–N bonds, poly(p-decyl anilino)silsesquioxane (PASQ), was successfully prepared using supramolecular template polymerization. The monomers 1,3-bis-(p-decyl anilino)-1,1,3,3-tetrachloro-disiloxanes first self-assembled into ladder superstructures (LSs) primarily through the synergistic interactions of hydrogen bonding and the van der Waals interactions, and then polymerized by adding water and triethylamine to produce a well-defined PASQ. The LSs was fully characterized using vapor pressure osmometry (VPO), UV–vis spectroscopy and X-ray diffraction (XRD). NMR and XRD measurements revealed that the PASQ was a ladder polymer. The reactivity of PASQ was confirmed by its Siacting with trimethylsilanol to form a ladder-like trimethylsiloxysilicate (LMQ). The ladder structure of LMQ was also thoroughly characterized, which further verified the ladder structural regularity of PASQ. [Copyright &y& Elsevier]

With the elaborate engineering of supra-amphiphiles basedon dualcharge-transfer interactions, the rational design and programmabletransformation of well-defined 1D and 2D nanostructures have beendemonstrated. First, H-shaped supra-amphiphiles are successfully obtainedon the basis of the directional charge-transfer interactions of naphthalenediimide and naphthalene, which self-assemble in water to form 2D nanosheets.Second, by complexation of the H-shaped supra-amphiphiles with pyrenederivatives, the 2D nanosheets transform into ultralong 1D nanofibers.Therefore, this line of research represents a successful example ofsupramolecular engineering and has enriched its realm. [ABSTRACT FROM AUTHOR]

With a rational design of the supra-amphiphiles, we have successfully demonstrated that not only the dimension of the self-assembled nanostructures, but also the packing fashion of the functional naphthalene diimide (a typical n-type chromophore), can be tuned in a noncovalent way in aqueous solution. Naphthalene diimide is incorporated into a bola-amphiphile as the rigid core, whereas viologen derivatives are used as the hydrophilic head. The bola-amphiphile self-assembles into two-dimensional nanosheets, in which naphthalene diimide adopts a 'J-type' aggregation. Water-soluble supramolecular complexation between viologen derivatives and the 8-hydroxypyrene-1, 3, 6-trisulfonic acid trisodium salt is used as a driving force for the formation of the supra-amphiphiles. Upon formation of the supra-amphiphiles, the nanosheets transform into ultralong nanofibers with a close packing of naphthalene diimide. Notably, just by mixing the two building blocks of the supra-amphiphiles in aqueous solution, a dimension-controlled evolution of the nanostructures is formed that leads to a different packing fashion of the n-type functional chromophores, which is facile and environmental friendly. [ABSTRACT FROM AUTHOR]

Abstract: Molecular self-assembly has become a versatile approach to create complex and functional nanoarchitectures. In this work, the self-assembly behavior of an anionic surfactant (sodium dodecylbenzene sulfonate, SDBS) and a hydrotropic salt (benzylamine hydrochloride, BzCl) in aqueous solution is investigated. Benzylamine hydrochloride is found to facilitate close packing of surfactants in the aggregates, inducing the structural transformation from SDBS micelles into unilamellar vesicles, and multilamellar vesicles. The multilamellar vesicles can transform into macroscale fibers, which are long enough to be visualized by the naked eye. Particularly, these fibers are robust enough to be conveniently separated from the surfactant solution. The combined effect of non-covalent interactions (e.g., hydrophobic effect, electrostatic attractions, and π–π interactions) is supposed to be responsible for the robustness of these self-assembled aggregates, in which π–π interactions provide the directional driving force for one-dimensional fiber formation. [Copyright &y& Elsevier]

Abstract: Two solution-processable star-shaped D–π–A organic molecules with triphenylamine (TPA) as donor unit, benzothiadiazole (BT) as acceptor unit and 4-hexyl-thienylenevinylene as pi conjugated bridge, S(TPA-TBTT) and S(TPA-TBTT-TPA), have been designed and synthesized for the application as donor materials in bulk-heterojunction organic solar cells (OSCs). The two molecules possess broader absorption from 350 to 700nm benefitted from the longer pi-bridge in the molecules but weaker absorbance and poorer solubility in comparison with their corresponding organic molecules with shorter vinylene pi-bridge. The OSC based on S(TPA-TBTT): PC70BM (1:3, w/w) exhibited J sc of 6.41mA/cm2, V oc of 0.75V, FF of 39.0% and power conversion efficiency of 1.90%, under the illumination of AM 1.5, 100mW/cm2. [Copyright &y& Elsevier]

Abstract: Branched alkylbenzenesulfonate gemini surfactants: sodium 6,6′-(propane-1,3-diylbis(oxy))bis(3-(2-propylpentyl)benzenesulfonate) (C8BC3C8B), sodium 6,6′-(propane-1,3-diylbis(oxy))bis(3-(3,5,5-trimethylhexyl)benzenesulfonate) (C9BC3C9B), and sodium 6,6′-(propane-1,3-diylbis(oxy))bis(3-(2,4,4-trimethylpentan-2-yl)benzenesulfonate) (T-C8BC3C8B) have been synthesized. Their interfacial activity and aggregation behavior in aqueous solution were studied by surface/interface tension measurement, electrical conductivity, isothermal titration microcalorimetry, 1H NMR spectroscopy, dynamic light scattering, steady-state fluorescence and cryogenic transmission electron microscopy. The critical aggregation concentration (CAC) and the minimum average surface area/molecule (A min) decrease with the decrease of the branching factor, i.e., in the order of T-C8BC3C8B, C8BC3C8B and C9BC3C9B. Moreover, alkyl side chain branches generate much more significant increases in CAC and A min for the gemini surfactants than single-chain surfactants. However, the branching factor does not change the air/water surface tension at CAC regularly. Instead, the air/water surface tension decreases with the increase of the carbon number of the hydrocarbon chains. In addition, it is noted that the branched gemini surfactants display high efficiency in reducing toluene/water interfacial tension. Interestingly, the increase in the branching factor leads to much more endothermic enthalpy of aggregation. All these three surfactants form spherical vesicles in aqueous solution and may present a parallel-displaced structure with a directional arrangement of the benzene ring in the vesicles. [Copyright &y& Elsevier]

Abstract: In the present work, in situ polymerization method was used to prepare nearly monodispersed microcapsules with long chain normal alkanes as core and melamine–formaldehyde (M–F) resin as shell at reaction temperature both above and below the cloud point of nonionic surfactant. A previously neglected point has been clarified, i.e., changing the reaction temperature is proved to be an effective way to tune the microcapsule size, surface pore size and density. Nano-scaled pores (from 5 to 200nm) on the microcapsule surface were formed by the self-assembly template of nonionic surfactant micelles at different reaction temperatures. The dynamic morphological evolution in the encapsulation process was illustrated, for the first time, by scanning electron microscopy (SEM) at different reaction time. It is the alteration of the hydrophilic–lipophilic balance of crosslinked M–F preploymer in the polymerization process that leads the micelle droplets to migrate inside out, and consequently forms nano- or submicron-pores on the microcapsule surface. The prepared microcapsules have close inner space, providing a good 3-dimensional environment for the confined crystallization of alkanes within the polymeric shell. This methodology is versatile and effective for the synthesis of other porous microspheres, which can be applied potentially for encapsulating lipophilic functional materials. [Copyright &y& Elsevier]

Bolaamphiphiles with l-glutamic acid headgroups and hybrid linkers, each composed of two rigid benzene rings and different polymethylene units, were designed, and morphological controls of the hierarchical self-assemblies were realized via changing solution pH and application to solid surfaces. At a low pH of 3, bolaamphiphiles formed hydrogels with water and molecules with short and long spacers formed nanofibers and helical nanoribbon−nanotubes, respectively. In a pH 12 aqueous solution, vesicles were observed from cryo-TEM measurements for amphiphiles with short spacers that could transfer to huge vesicles when cast onto a mica surface. Amphiphiles with longer spacers self-assembled into nanoparticles in a pH 12 aqueous solution while micellar fibers were formed on a mica surface. Those assemblies were characterized with UV−vis, CD, and FT-IR spectroscopy and AFM and TEM observations. With molecular structure modification and the fine tuning of conditions, morphology transitions between various nanostructures were obtained from the self-assembled bolaamphiphiles. The environmental pH can induce different interaction modes between the headgroups, and at high pH, there are strong interactions between molecular assemblies and the mica surface. It is suggested that the active headgroups, rigid necks, and flexible linkers with different lengths render molecules with diverse aggregation morphologies. [ABSTRACT FROM AUTHOR]

Abstract: Herein, we present a concept of combining host–guest chemistry with block copolymer self-assembly to fabricate an inner cross-linking block copolymer aggregate with photo-responsive switches on the basis of the reversible interaction between azobenzene and β-cyclodextrin, which can serve as a controllable supramolecular container to load and release guest molecules reversibly. The inner cross-link makes the block copolymer aggregates exhibit good stability, and the aggregates can keep their spherical morphologies during photo-irradiation treatment. When the switches are in on-state, cyclodextrins can bind with hydrophobic pyrene molecules; and when the switches are in off-state, pyrene molecules will get away from the cyclodextrins. The photo-controllable switches embedded in the aggregates endow this new supramolecular container with the capability to load and release guest molecules reversibly without structure disruption. It is anticipated that this line of work may open an avenue for fabricating new polymeric containers which can be used for controllable molecular transfer and catalysis. [Copyright &y& Elsevier]

Ultrahigh molecular weight polyethylene (UHMWPE) is a class of high-performance engineering plastics, exhibiting a unique set of properties and applications. Although many advances have been achieved in recent years, the synthesis of UHMWPE is still a great challenge. In this contribution, a series of zirconium and hafnium complexes, [2,6-(R1)2-4-R2-C6H2-N-C(camphyl)=C(camphyl)-N-2,6-(R1)2-4-R2-C6H2]MMe2(THF) (1-Zr: R1 = Me, R2 = H, M = Zr; 2-Zr: R1 = Me, R2 = Me, M = Zr; 1-Hf: R1 = Me, R2 = H, M = Hf; 2-Hf: R1 = Me, R2 = Me, M = Hf), bearing bidentate NN ligands with the bulky camphyl backbone were synthesized by the stoichiometric reactions of α-diimine ligands with MMe4 (M = Hf or Zr). All Zr and Hf metal complexes were analyzed using 1H and 13C NMR spectroscopy, and the molecular structures of complexes 1-Zr and 1-Hf were determined by single-crystal X-ray diffraction, revealing that the original α-diimine ligand was selectively reduced into the ene-diamido form and generated an 1,3-diaza-2-metallocyclopentene ring in the metal complexes. Zr complexes 1-Zr and 2-Zr showed moderate activity (up to 388 kg(PE)·mol−1(M)·h−1), poor copolymerization ability, but unprecedented molecular weight capability toward ethylene/1-octene copolymerization. Therefore, copolymers with ultrahigh molecular weights (>600 or 337 × 104 g∙mol−1) were successfully synthesized by 1-Zr or 2-Zr, respectively, with the borate cocatalyst [Ph3C][B(C6F5)4]. Surprisingly, Hf complexes 1-Hf and 2-Hf showed negligible activity under otherwise identical conditions, revealing the great influence of metal centers on catalytic performances. [ABSTRACT FROM AUTHOR]

Multi-energy flow (MEF) analysis is the most fundamental issue in studying multi-energy carrier (MEC) systems. In the tight coupling MEC systems, the unified energy flow analysis is indispensable to tackle the problems of accuracy and in decomposition. Therefore, on the basis of the comprehensive node classification and modified Jacobian matrix, this paper proposes a unified energy flow analysis approach with Newton method considering initial guesses selection for complex MEC systems including electrical, gas, heating sub-networks. This approach is based on the presented convergence theorem, which can determine in advance whether the initialization can converge to results, since the Newton method, the main approach of the unified energy flow analysis, is sensitive to its initial guesses selection. Once the initialization can not converge, the proposed approach can help selecting proper initial guesses for Newton method to guarantee the convergence of the unified energy flow. Several cases are studied to demonstrate the effectiveness and applicability of the proposed approach on judging and choosing initialization for the unified energy flow analysis. • A unified energy flow analysis approach is proposed for multi-energy carrier systems. • The convergence theorem for Newton-Raphson solving energy flow is proposed. • The comprehensive node classification and several novel slack types are presented. • The more realistic heating Jacobian matrix is utilized. • Different scales of multi-energy carrier systems are considered. [ABSTRACT FROM AUTHOR]

A new polystyrene supported cyclic trimeric phosphazene base (PS-CTPB) was designed and synthesized. It was demonstrated that hypotoxic poly (ε -caprolactone) (PCL) can be directly prepared via ring-opening polymerization (ROP) by using PS-CTPB as catalyst. The PS-CTPB catalyst was prepared via immobilization of cyclic trimeric phosphazene base (CTPB) moiety on polystyrene microspheres to obtain a heterogeneous organocatalyst. The composition and chemical structure of the heterogeneous PS-CTPB was systematically characterized using solid-state 13C and 31P MAS NMR, FTIR, SEM and element analysis. It was found that immobilization of CTPB on PS microsphere maintained its excellent catalytic activity for ROP of ε -CL, δ -valerolactone (δ -VL), rac -lactide (rac -LA). Moreover, the heterogeneous PS-CTPB could be easily separated or recycled via simple filtration. Given that, the obtained polyesters contained negligible catalyst residual, so the obtained PCL samples have low cytotoxicity indicated from MTT assay. It was worth noting that the recycled PS-CTPB catalyst could be reused for another six consecutive cycles without significant decrease of catalytic activity. Image 1 • PS-CTPB is prepared via immobilization of cyclic trimeric phosphazene base moiety on polystyrene microspheres. • PS-CTPB exhibits highly efficient for ring-opening polymerization of cyclic esters. • PS-CTPB is easily recovered and reusable for six consecutive cycles without obvious deactivation. • The PCLs without catalyst-residue have been facilely synthesized using PS-CTPB by simple filtration. • MTT assay indicates that the resulting PCLs have low cytotoxicity. [ABSTRACT FROM AUTHOR]

We report the biomimetic synthesis of polyethylene glycol (PEG) grafted silica nanoplates templated by double hydrophilic PEG-b-poly-l-lysine diblock copolymers. The silica nanoplates can be re-dispersed in PEG selective solvents. The sizes of silica nanoplates can be tuned from a few hundred nanometers to tens of micrometers. [ABSTRACT FROM AUTHOR]

Keywords: crystallinity; electrochemistry; graphdiyne; interfaces; thin films EN crystallinity electrochemistry graphdiyne interfaces thin films 7732 7732 1 06/25/20 20200623 NES 200623 B Fabrication of ultrathin b and highly crystalline GDY film is of vital importance for studies of their intrinsic properties. This work reports the successful application of a liquid/liquid/gel system for confined synthesis of GDY film with high quality in a controllable way. [Extracted from the article]

Organocatalytic, metal‐free ring‐opening alternating copolymerization (ROAP) of epoxides and cyclic anhydrides to produce polyesters with well‐defined alternating structure remains a challenge despite several organocatalysts having been reported. Herein, the ROAP of cyclohexene oxide (CHO) with phthalic anhydride (PA) using a series of carboxylic acids as initiator in the presence of an organic cyclic trimetric phosphazene base (CTPB) as catalyst is reported. The molar ratio of CTPB to carboxylic acid is proven to be crucial to obtain polyester with well‐defined alternating structure without formation of polyether homopolymer. The effects of carboxylic acid, temperature and feed molar ratio on monomer conversions and resultant molecular weights of poly(PA‐alt‐CHO) are systematically investigated. This work enriches the opinion of initiator for the ROAP of epoxides and cyclic anhydrides. [ABSTRACT FROM AUTHOR]

• We incorporate the methine groups of heptamethine cyanines into the cyclic frame to construct a new near-infrared (NIR) molecular rotor Mu1. • Mu1 is superior to the traditional cyanines with high viscosity response, large stokes shift (˜100 nm), high photo-stability and selectivity. • Mu1 can ratiometrically track mitochondrial viscosity changes in live cells with high spatial and temporal resolution. We developed a new cyanine-derived near-infrared (NIR) molecular rotor Mu1 , which is superior to the traditional cyanines with high viscosity response, large Stokes shift (˜100 nm), and high photo-stability to detect the microscopic viscosity ratiometrically. The time-dependent density functional theory calculations highlighted the structure-optical properties of Mu1 as molecular rotor. Due to the mitochondria-actived fluorescence characteristics, Mu1 was used to track mitochondrial viscosity changes in live cells with high spatial and temporal resolution. This new type of NIR molecular rotor presented herein may open up new opportunities of NIR sensors for biomedical diagnosis and imaging applications. [ABSTRACT FROM AUTHOR]

A B-modified Mo 3 Si coating was fabricated on a pure Mo substrate by the plasma transferred arc (PTA) cladding process. The microstructure, phase constitution, and oxidation resistance of the coating were studied to determine the effect of B addition. The microstructure characterization shows that the coarse Mo 3 Si dendrites and few small dispersed Mo 5 Si 3 particles are uniformly distributed in the Mo 3 Si/Mo 5 SiB 2 eutectics matrix. Compared to both the pure Mo and Mo 3 Si reference materials, the B-modified Mo 3 Si coating exhibits a drastic improvement in oxidation resistance, which can be ascribed to a complete surface coverage by a borosilicate glass scale produced during the high temperature oxidation exposure to air at 1300 °C. Upon oxidation small additions of B into Mo 3 Si compound promotes the rapid formation of a dense and continuous borosilicate glass scale and improves its viscous flow on the coating surface, restricting the inward oxygen diffusion to the oxidation interface, and thereby enhancing its oxidation resistance. Image 1 • A B-modified Mo 3 Si coating was fabricated by the PTA process. • The microstructure and oxidation resistance of the coating were studied. • The B-modified Mo 3 Si coating exhibited a drastic improvement in oxidation resistance at 1300 °C in air. • Small addition of B into Mo 3 Si promoted the rapid formation and viscous flow of the borosilicate scale upon oxidation. [ABSTRACT FROM AUTHOR]

Over the past several years, organocatalyzed polymerization reactions have attracted considerable attention, and these efforts have led to major advances. A large number of organic compounds have been proven active for the polymerization of a large variety of monomers. In particular, phosphazene bases (PBs) are a family of extremely strong, non‐nucleophilic, and uncharged auxiliary bases, and have shown their remarkable potential as organocatalysts for the ring‐opening polymerization (ROP) of cyclic monomers. By deprotonation of weak acids or in combination with lithium cation, PBs significantly enhance the nucleophilicity of the initiator/chain‐end, thus allowing fast and usually controlled anionic polymerization. In this feature article, the recent advances in phosphazene‐catalyzed ROP of cyclic esters are summarized. This review is divided into three sections, including general features, design and synthesis, and catalytic applications. It aims to provide a critical analysis of PB‐mediated ROP systems and a useful guide for the further design of organocatalysts applied to polymer synthesis. An outlook is given at the end. Phosphazene bases (PBs) are a family of extremely strong and non‐nucleophilic bases having remarkable potential as organocatalysts for different types of polymerization reactions. This feature article emphasizes the general features and synthetic methods of PBs and focuses on their applications in the ring‐opening polymerization of cyclic ester monomers. [ABSTRACT FROM AUTHOR]

The first utilization of nitrogen‐doped graphdiyne (NGDY) as an efficient catalytic promoter for hydrogen evolution reaction (HER) is reported. X‐ray powder diffraction and X‐ray photoelectron spectroscopy studies indicate the presence of strong interactions between NGDY and MoS2, which should effectively facilitate the charge transport behavior and improvement of the HER kinetics. The creative hybridization of MoS2 and NGDY endows such heterostructure with structural and compositional advantages for boosting the catalytic activity (low overpotential of 186 mV at 10 mA cm−2 and Tafel slope of 63 mV dec−1) and extraordinary stability (higher than all reported MoS2‐based materials and even better than that of commercial Pt and almost all benchmarked electrocatalysts). All of the results not only demonstrate that NGDY can be used as an effective catalytic promoter for hydrogen production, but also provide new strategy for fabricating efficient water‐splitting electrodes. The creative hybridization of MoS2 and nitrogen‐doped graphdiyne endows such heterostructure with structural and compositional advantages and highly associated interactions, which effectively facilitate the charge transport behavior and hydrogen evolution reaction (HER) kinetics, leading to greatly enhancement in the intrinsic HER catalytic activities and outstanding stability in acidic conditions. [ABSTRACT FROM AUTHOR]

The linear alkyl chain length effect on the assembly of non ‐ planar perylene bisimides (PBIs, 1 with ‐ C6H13; 2 with ‐ C12H25) has been investigated. It was suggested that π–π stacking predominated in assemblies of 1 with short alkyl chains, while both π–π stacking and van der Waals interactions contributed to the hierarchical assembly of 2 with longer alkyl chains. Thus, by changing the linear chain length, the hierarchical assembly of PBIs modified on bay positions could be manipulated effectively. More information can be found in the Full Paper by Zongxia Guo, Zhibo Li et   al. on page   2827 in Issue 21, 2017 (DOI:10.1002/asia.201700984). [ABSTRACT FROM AUTHOR]

Size of destiny! 2D crystallization of rylene diimide ‐ based n ‐ type semiconductors was explored at the liquid/HOPG interface by means of scanning tunneling microscopy (STM). It was found that the dimension size of the aromatic core affects the surface assembly behaviors of such n ‐ type semiconductors. The 2D patterns and the surface chirality can also be tuned by solvent nature. In addition, the long ‐ range ordered properties of the monolayers can be adjusted by changing the molecular symmetry. More information can be found in the Full Paper by Zongxia Guo, Zhibo Li et al. on page   1104 in Issue 10, 2017 (DOI: 10.1002/asia.201700271). [ABSTRACT FROM AUTHOR]

Review: most recent progress in stimuli-responsive polypeptides over the past decade; 51 refs. [ABSTRACT FROM AUTHOR]