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Bottom-up methods for the fabrication of nanoporous polymer membranes have numerous advantages. However, it remains challenging to fabricate nanoporous membranes that are mechanically robust and have aligned pores, that is, with a low tortuosity. Here, a mechanically robust thin-film composite membrane was fabricated consisting of a two-dimensional (2D) porous smectic liquid crystalline polymer network inside an anisotropic, microporous polymer scaffold. The polymer scaffold allows for relatively straightforward planar alignment of the smectic liquid crystalline mixture, which consisted of a diacrylate cross-linker and a dimer forming benzoic acid-based monoacrylate. Polymerized samples displayed a smectic A (SmA) phase, which formed the eventual 2D porous channels after base treatment. The aligned 2D nanoporous membranes showed a high rejection of anionic solutes bigger than 322 g/mol. Cleaning and reusability of the system were demonstrated by intentionally fouling the porous channels with a cationic dye and subsequently cleaning the membrane with an acidic solution. After cleaning, the membrane properties were unaffected; this, combined with numerous pressurizing cycles, demonstrated reusability of the system.

The photodegradation of 2-chlorobenzoic acid (2-CBA) in suspensions of TiO 2 was examined under different operational parameters. The optimal condition could be obtained through the experiment, i.e. that the concentration of 2-CBA was 30 mg/L and the dosing quantity of TiO 2 was 0.01 g under UV light in the case of pH 3.5. Above reaction process was in accordance with first order kinetics model. The influence on photocatalytic degradation caused by typical anions in eutrophicated water body such as NO 3 and H - and H 2 PO 4 , and the reaction route of 2-CBA could be predicted through the analysis on the intermediate.- was explored in this work, which revealed that both two anions had inhibitory effect on the degradation process. In addition, alcohol was introduced into the process to identify the degradation mechanism of 2-CBA with TiO 2 , and the reaction route of 2-CBA could be predicted through the analysis on the intermediate., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 Published by Elsevier B.V. on behalf of King Saud University.)

Metal-organic frameworks (MOFs) as additives in mixed matrix membranes (MMMs) for gas separation have gained significant attention over the past decades. Many design parameters have been investigated for MOF based MMMs, but the spatial distribution of the MOF throughout MMMs lacks investigation. Therefore, magnetically aligned and enriched pathways of zeolitic imidazolate framework 8 (ZIF-8) in Matrimid MMMs were synthesized and investigated by means of their N 2 and CO 2 permeability. Magnetic ZIF-8 (m-ZIF-8) was synthesized by incorporating Fe 3 O 4 in the ZIF-8 structure. The presence of Fe 3 O 4 in m-ZIF-8 showed a decrease in surface area and N 2 and CO 2 uptake, with respect to pure ZIF-8. Alignment of m-ZIF-8 in Matrimid showed the presence of enriched pathways of m-ZIF-8 through the MMMs. At 10 wt.% m-ZIF-8 incorporation, no effect of alignment was observed for the N 2 and CO 2 permeability, which was ascribed anon-ideal tortuous alignment. However, alignment of 20 wt.% m-ZIF-8 in Matrimid showed to increase the CO 2 diffusivity and permeability (19%) at 7 bar, while no loss in ideal selectivity was observed, with respect to homogeneously dispersed m-ZIF-8 membranes. Thus, the alignment of MOF particles throughout the matrix was shown to enhance the CO 2 permeability at a certain weight content of MOF.

Bacterial cellulose(BC) is a kind of extracellular polymer synthesized by bacteria and it has very wide applications in many fields. However, the application of BC in a large commercial scale can still not be fulfilled due to the low yield and demanding for BC membranes with very different properties. To this end, a new BC-producer Komagataeibacter rhaeticus TJPU03 was isolated from rotten orange peel, which produced 8.28 ± 0.27 g/L(dry weight) in standard HS medium at the 10th day. The membrane is easier to be purified by one-step alkaline treatment and the produced BC(K-BC) membranes possess homogeneous, looser and more porous three-dimensional network composed by thinner cellulose fibrils. However, the wet K-BC possesses stronger mechanical properties and exhibits lower toxicity and higher cytocompatibility to mammalian cell. Owing to the more porous and homogeneous network, K-BC possesses high loading capacity of cell and protein drugs. Also, it exhibits sustained-controlled release ability for proteinaceous drug. The high yield of this strain and the special characteristics of K-BC predict this strain to be a very promising BC-producer and broad applications of K-BC in the fields of wound healing, scaffolds of tissue engineering, tissue repair and regeneration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Oligonuclear complexes of d 4 -d 7 transition metal ion centers that undergo spin-switching have long been developed for their practical role in molecular electronics. Recently, they also have appeared as promising photochemical reactants demonstrating improved stability. However, the lack of knowledge about their photophysical properties in the solution phase compared to mononuclear complexes is currently hampering their inclusion into advanced light-driven reactions. In the present study, the ultrafast photoinduced dynamics in a solvated [2 × 2] iron(II) metallogrid complex are characterized by combining measurements with transient optical-infrared absorption and x-ray emission spectroscopy on the femtosecond time scale. The analysis is supported by density functional theory calculations. The photocycle can be described in terms of intra-site transitions, where the Fe II centers in the low-spin state are independently photoexcited. The Franck-Condon state decays via the formation of a vibrationally hot high-spin (HS) state that displays coherent behavior within a few picoseconds and thermalizes within tens of picoseconds to yield a metastable HS state living for several hundreds of nanoseconds. Systematic comparison with the closely related mononuclear complex [Fe(terpy) 2 ] 2+ reveals that nuclearity has a profound impact on the photoinduced dynamics. More generally, this work provides guidelines for expanding the integration of oligonuclear complexes into new photoconversion schemes that may be triggered by ultrafast spin-switching.

Application of forward osmosis (FO) is limited due to membrane fouling and, most importantly, high reverse salt fluxes that deteriorate the concentrated product. Polydopamine (PDA) is a widely used, easily applicable, hydrophilic, adhesive antifouling coating. Among the coating parameters, surprisingly, the effect of PDA coating temperature on the membrane properties has not been well studied. Polyethersulfone (PES) 30 kDa ultrafiltration membranes were PDA-coated with varying dopamine concentrations (0.5-3 g/L) and coating temperatures (4-55 °C). The quality of the applied coating has been determined by surface properties, water permeability and reverse salt flux using a 1.2 M MgSO 4 draw solution. The coating thickness increased both with the dopamine concentration and coating temperature, the latter having a remarkably stronger effect resulting in a higher PDA deposition speed and smaller PDA aggregates. In dead‑end stirred cell, the membranes coated at 55 °C with 2.0 g/L dopamine showed NaCl and MgSO 4 retentions of 41% and 93%, respectively. In crossflow FO, a low reverse MgSO 4 flux (0.34 g/m 2 ·h) was found making a very low specific reverse salt flux (J s /J w ) of 0.08 g/L, which outperformed the commercial CTA FO membranes, showing the strong benefit of high temperature PDA-coated PES membranes to assure high quality products.

Ideal wound dressing materials should be active components in the healing process. Bacterial cellulose (BC) has attracted a great deal of attention as novel wound dressing materials; however, it has no intrinsic antimicrobial activity. To explore the practical application values of BC and develop novel wound dressing materials, a series of composite membranes based on BC and polymeric ionic liquids (BC/PILs, composed of BC, and PILs formed by choline and different amino acids) with antimicrobial activity were synthesized by an ex situ method. The physicochemical and antimicrobial properties and biocompatibility of these membranes were systematically investigated. The results indicated that BC/PIL membranes with excellent properties could be obtained by adjusting the concentration and type of PILs. Several kinds of BC/PIL membranes exhibited good biocompatibility and high antimicrobial activity against Gram-positive and Gram-negative bacteria and fungus. The anionic PILs played important roles in the antimicrobial activity of BC/PIL membranes. The obtained membranes provided a novel promising candidate for wound dressing materials.

Chitin is the most widely distributed oceanic biomass resources. Its monomer unit, N-acetyl- D -glucosamine (NAG), contains precious atomic nitrogen and represents a potential feedstock for the manufacture of regenerative organic nitrogen chemicals. Herein, the conversion of NAG to the platform chemical, 3-acetamido-5-acetylfuran (3A5AF), catalyzed by amino acid ionic liquids, was investigated. The reaction, catalyzed by a very small amount of glycine chloride ionic liquid without any additives, could yield 43.22% 3A5AF in 10 min. By adding CaCl 2 , a higher yield up to 52.61% was obtained. This work demonstrated the conversion of chitin biomass to 3A5AF in higher yield without using a boron-based catalyst for the first time. Moreover, the ionic liquid catalyst exhibited excellent recyclability, and afforded 43.22-36.59% yield over during eight cycles. This research provides new and green procedures to convert shellfish fishery waste into value-added platform chemicals., (Copyright © 2019. Published by Elsevier B.V.)

An atomistic understanding of the photoinduced spin-state switching (PSS) within polynuclear systems of d 4 -d 7 transition metal ion complexes is required for their rational integration into light-driven reactions of chemical and biological interest. However, in contrast to mononuclear systems, the multidimensional dynamics of the PSS in solvated molecular arrays have not yet been elucidated due to the expected complications associated with the connectivity between the metal centers and the strong interactions with the surroundings. In this work, the PSS in a solvated triiron(II) metallogrid complex is characterized using transient optical absorption and X-ray emission spectroscopies on the femtosecond time scale. The complementary measurements reveal the photoinduced creation of energy-rich (hot) and long-lived quintet states, whose dynamics differ critically from their mononuclear congeners. This finding opens major prospects for developing novel schemes in solution-phase spin chemistry that are driven by the dynamic PSS process in compact oligometallic arrays.

A variety of biomedical applications requires tailored membranes; fabrication through a mix-and-match approach is simple and desired. Polymers based on supramolecular bis-urea (BU) moieties are capable of modular integration through directed non-covalent stacking. Here, it is proposed that non-cell adhesive properties can be introduced in polycaprolactone-BU-based membranes by the addition of poly(ethylene glycol) (PEG)-BU during immersion precipitation membrane fabrication, while unmodified PEG is not retained in the membrane. PEG-BU addition results in denser membranes with a similar pore size compared to pristine membranes, while PEG addition induces defect formation. Infrared spectroscopy and surface hydrophobicity measurements indicate that PEG-BU is retained during membrane processing. Additionally, PEG-BU incorporation successfully leads to poor cell adhesive surfaces. No evidence is observed to indicate PEG retention. The results obtained indicate that the BU system enables intimate mixing of BU-modified polymers after processing. Collectively, the results provide the first steps toward BU-based immersion precipitated supramolecular membranes for biomedical applications., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Managing the gas-liquid interface within gas-diffusion electrodes (GDEs) is key to maintaining high product selectivities in carbon dioxide electroreduction. By screening silver-catalyzed GDEs over a range of applied current densities, an inverse correlation was observed between carbon monoxide selectivity and the electrochemical double-layer capacitance, a proxy for wetted electrode area. Plotting current-dependent performance as a function of cumulative charge led to data collapse onto a single sigmoidal curve indicating that the passage of faradaic current accelerates flooding. It was hypothesized that high cathode alkalinity, driven by both initial electrolyte conditions and cathode half-reactions, promotes carbonate formation and precipitation which, in turn, facilitates electrolyte permeation. This mechanism was reinforced by the observations that post-test GDEs retain less hydrophobicity than pristine materials and that water-rinsing and drying electrodes temporarily recovers peak selectivity. This knowledge offers an opportunity to design electrodes with greater carbonation tolerance to improve device longevity., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Photoactive transition-metal complexes that incorporate heteroleptic ligands present a first coordination shell, which is asymmetric. Although it is generally expected that the metal-ligand bond lengths respond differently to photoexcitation, resolving these fine structural changes remains experimentally challenging, especially for flexible multidentate ligands. In this work, ultrafast X-ray absorption spectroscopy is employed to capture directly the asymmetric elongations of chemically inequivalent metal-ligand bonds in the photoexcited spin-switching Fe II complex [Fe II (tpen)] 2+ solvated in acetonitrile, where tpen denotes N , N , N ', N '-tetrakis(2-pyridylmethyl)-1,2-ethylenediamine. The possibility to correlate precisely the nature of the donor/acceptor coordinating atoms to specific photoinduced structural changes within a binding motif will provide advanced diagnostics for optimizing numerous photoactive chemical and biological building blocks., Competing Interests: The authors declare no competing financial interest.

Salinity gradient energy is a sustainable, renewable, and clean energy source. When waters with different salinities are mixed, the change in Gibbs free energy can be harvested as energy and only brackish water remains. Reverse electrodialysis is one of the technologies that can harvest this sustainable energy source. High power densities have been obtained in small lab scale systems, but translation to large industrial scale stacks is essential for commercialization of the technology. Moreover, power density is an important parameter, and efficiency, i.e., the amount of energy harvested compared to the amount of energy available in the feed waters, is critical for commercial processes. In this work, we systematically investigate the influence of stack size and membrane type on power density, thermodynamic efficiency, and energy efficiency. Results show that the residence time is an excellent parameter for comparing differently sized stacks and translating lab scale experimental results to larger pilot stacks. Also, the influence of undesired water permeability and co-ion diffusion (as reflected in permselectivity) is clearly visible when measuring the thermodynamic efficiency. An averaged thermodynamic efficiency of 44.9% is measured using Fujifilm Type 10 anion exchange and cation exchange membranes that have low water permeability and high permselectivity. This value comes close to the thermodynamic maximum of 50%.

Photoelectrocatalytic (PEC) system greatly improves the migration of photoexcited charges, retards the fast recombination of electron-hole and increases the lifetime of photogenerated holes. In this article, we constructed a novel PEC system to degrade berberine chloride form (BCF). XRD patterns indicated aging time was an important condition for the crystal type of TiO 2, and the best proportion of anatase/rutile was 80/20. The band gap energy of the TiO 2 was 3.01 eV. We demonstrated that a synergistic effect existed between photocatalysis (PC) and electrocatalysis (EC). Besides, we discussed the influence of pH, current density, the amount of catalyst and initial BCF concentration on the degradation of BCF. Electron spin resonance (ESR) through spin trap 5, 5-dimethyl-1-pyrroline-N-oxide (DMPO) and the scavenging experiments suggested that the reactive oxygen species (ROS) were superoxide radicals (O2·-), hydroxyl radicals (·OH) and sulfate radical (SO4·-) in PEC system. Furthermore, we compared the two pathway of formation DMPO-SO 4 adducts and found that SO4·- was the most major oxidized species in degrading BCF. We proposed a plausible reaction mechanism. Intriguingly, even under lower current and weaker light conditions, the PEC process maintained its effectiveness, demonstrating the feasibility of the PEC approach., (© 2018 The American Society of Photobiology.)

Divalent cations in feedwater can cause significant decreases in efficiencies for membrane processes, such as reverse electrodialysis (RED). In RED, power is harvested from the mixing of river and seawater, and the obtainable voltage is reduced and the resistance is increased if divalent cations are present. The power density of the RED process can be improved by removing divalent cations from the fresh water. Here, we study divalent cation removal from fresh water using seawater as draw solution in a Donnan dialysis (DD) process. In this way, a membrane system with neither chemicals nor electrodes but only natural salinity gradients can be used to exchange divalent cations. For DD, the permselectivity of the cation exchange membrane is found to be crucial as it determines the ability to block salt leakage (also referred to as co-ion transport). Operating DD using a membrane stack achieved a 76% reduction in the divalent cation content in natural fresh water with residence times of just a few seconds. DD pretreated fresh water was then used in a RED process, which showed improved gross and net power densities of 9.0 and 6.3%, respectively. This improvement is caused by a lower fresh water resistance (at similar open circuit voltages), due to exchange of divalent for monovalent cations., Competing Interests: The authors declare no competing financial interest.

Fe 2 O 3 /graphite (Fe 2 O 3 /C) and nano-TiO 2 -coated glass bead were prepared by impregnation and sol-gel method respectively and employed as the catalyst of a novel three-dimensional electrode photoelectrocatalytic (3-D PEC) system. The photoexcited electrons can transfer from TiO 2 , Fe 2 O 3 to counter electrode. It improves the migration of photoexcited charges, retards the fast recombination of electron-hole, and increases the lifetime of photogenerated holes (h + ). In addition, the cycle reaction of Fe 3+ /Fe 2+ on Fe 2 O 3 /C surface enhanced the Fenton reaction which can produce more hydroxyl radicals (·OH) and promote the capacity of mineralization of the pollutants. This novel 3-D PEC system showed excellent performance for the degradation of berberine chloride form (BCF). At the pH value of 3, 93% BCF was removed within 60 min; besides, 98.64% COD removal rate, 78.96% mineralization, 21.47% mineralization current efficiency, and just 3.16 kW h g -1 TOC energy cost were obtained in 120 min. In this study, we proposed the 3-D PEC mechanism. Electron spin resonance (ESR) and scavenging experiments suggest that the major reactive oxygen species (ROS) are superoxide radicals (O 2 ), ·OH, and h ·- ), ·OH, and h + ) is insignificant. This work provides a new dimension for the design of reactors for wastewater treatment and the construction of the 3-D PEC system can potentially be utilized in water purification.4 ·- ) is insignificant. This work provides a new dimension for the design of reactors for wastewater treatment and the construction of the 3-D PEC system can potentially be utilized in water purification.

With a fantastic combination of yeast fermentation and hydrogel membrane formation, a series of microorganism inspired porous hydrogel membranes (MIHM) with various mass ratios of yeast/sodium alginate (SA) were developed. The yeast cells were firstly activated by addition of glucose for generating byproduct carbon dioxide (CO 2 ), inducing the formation of porous structures. The ionic cross-linking between calcium chloride and SA was subsequently performed based on an egg-box model. It is of interest to note that the obtained MIHM hydrogel membranes exhibited decreased transparency and hierarchical porous structure with pore sizes varying from 2 nm to 1 mm, giving rise to significantly increased contact angle (CA) values from 63.65° to 107.83° and obviously decreased equilibrium swelling ratios from 79.72 to 18.05. Especially, the adsorption kinetics of crystal violet (CV) show that the MIHM hydrogel membrane exhibited an encouraging uptake capacity of 18.40 mg g -1 at 10 mg g -1 and the adsorption kinetics of CV could be well defined by a pseudo-first-order kinetic equation. Owing to great advantages in facile fabrication, high efficiency, low cost and desirable biocompatibility, the MIHM hydrogel membrane can be large-scale fabricated and used for industry and agriculture., Competing Interests: The authors declared that they have no conflicts of interest to this work. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (This journal is © The Royal Society of Chemistry.)

Investigating the photoinduced electronic and structural response of bistable molecular building blocks incorporating transition metals in solution phase constitutes a necessary stepping stone for steering their properties toward applications and performance optimizations. This work presents a detailed X-ray transient absorption (XTA) spectroscopy study of a prototypical spin crossover (SCO) complex [Fe II (mbpy) 3 ] 2+ (where mbpy = 4,4'-dimethyl-2,2'-bipyridine) with an [Fe II N 6 ] first coordination shell in water (H 2 O) and acetonitrile (CH 3 CN). The unprecedented data quality of the XTA spectra together with the direct fitting of the difference spectra in k space using a large number of scattering paths enables resolving the subtle difference in the photoexcited structures of an Fe II complex in two solvents for the first time. Compared to the low spin (LS) 1 A 1 state, the average Fe-N bond elongations for the photoinduced high spin (HS) 5 T 2 state are found to be 0.181 ± 0.003 Å in H 2 O and 0.199 ± 0.003 Å in CH 3 CN. This difference in structural response is attributed to ligand-solvent interactions that are stronger in H 2 O than in CH 3 CN for the HS excited state. Our studies demonstrate that, although the metal center of [Fe II (mbpy) 3 ] 2+ could have been expected to be rather shielded by the three bidentate ligands with quasi-octahedral coordination, the ligand field strength in the HS excited state is nevertheless indirectly affected by solvation effects that modifies the charge distribution within the Fe-N covalent bonds. More generally, this work highlights the importance of including solvation dynamics in order to develop a generalized understanding of the spin-state switching at the atomic level.

The removal of sulfamethazine (SMT), tetracycline (TC) and chloramphenicol (CP) from synthetic wastewater by raw (M 3 ) and nitrogen plasma modified steel shavings (M 3 -plN 2 ) was investigated using batch experiments. The adsorption kinetics could be expressed by both pseudo-first-order kinetic (PFO) and pseudo-second-order kinetic (PSO) models, where correlation coefficient r 2 values were high. The values of PFO rate constant k 1p and PSO rate constant k 2p decreased as SMT-M 3 >SMT-M 3 -plN 2 >TC-M 3 -plN 2 >TC-M 3 >CP-M 3 >CP-M 3 -plN 2 and SMT-M 3 >SMT-M 3 -plN 2 >TC-M 3 >TC-M 3 -plN 2 >CP-M 3 >CP-M 3 -plN 2 , respectively. Solution pH, adsorbent dose and temperature exerted great influences on the adsorption process. The plasma modification with nitrogen gas cleaned and enhanced 1.7-fold the surface area and 1.4-fold the pore volume of steel shavings. Consequently, the removal capacity of SMT, TC, CP on the adsorbent rose from 2519.98 to 2702.55, 1720.20 to 2158.36, and 2772.81 to 2920.11μg/g, respectively. Typical chemical states of iron (XPS in Fe2p3 region) in the adsorbents which are mainly responsible for removing antibiotics through hydrogen bonding, electrostatic and non- electrostatic interactions and redox reaction were as follows: Fe 3 O 4 /Fe 2+ , Fe 3 O 4 /Fe 3+ , FeO/Fe 2+ and Fe 2 O 3 /Fe 3+ ., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Reverse electrodialysis (RED) is a membrane-based renewable energy technology that can harvest energy from salinity gradients. The anticipated feed streams are natural river and seawater, both of which contain not only monovalent ions but also divalent ions. However, RED using feed streams containing divalent ions experiences lower power densities because of both uphill transport and increased membrane resistance. In this study, we investigate the effects of divalent cations (Mg 2+ and Ca 2+ ) on RED and demonstrate the mitigation of those effects using both novel and existing commercial cation exchange membranes (CEMs). Monovalent-selective Neosepta CMS is known to block divalent cations transport and can therefore mitigate reductions in stack voltage. The new multivalent-permeable Fuji T1 is able to transport divalent cations without a major increase in resistance. Both strategies significantly improve power densities compared to standard-grade CEMs when performing RED using streams containing divalent cations.

Topological structures of bio-architectonics and bio-interfaces play major roles in maintaining the normal functions of organs, tissues, extracellular matrix, and cells. In-depth understanding of natural self-assembly mechanisms and mimicking functional structures provide us opportunities to artificially control the natural assemblies and their biofunctions. Here, we report an intracellular enzyme-catalyzed polymerization approach for efficient synthesis of polypeptides and in situ construction of topology-controlled nanostructures. We reveal that the phase behavior and topological structure of polypeptides are encoded in monomeric peptide sequences. Next, we elucidate the relationship between polymerization dynamics and their temperature-dependent topological transition in biological conditions. Importantly, the linearly grown elastin-like polypeptides are biocompatible and aggregate into nanoparticles that exhibit significant molecular accumulation and retention effects. However, 3D gel-like structures with thermo-induced multi-directional traction interfere with cellular fates. These findings allow us to exploit new nanomaterials in living subjects for biomedical applications.

Carbon nanotube (CNT)-reinforced mesoporous hydroxyapatite (HA) composites with excellent mechanical and biological properties were fabricated successfully by the in situ chemical deposition of mesoporous HA on homogeneously dispersed CNTs. The CNTs are first synthesized in situ on HA nanopowders by chemical vapor deposition, and then, the HA particles with mesoporous structures are deposited in situ onto the as-grown CNTs by using cetyl trimethyl ammonium bromide as templates to form mesoporous HA encapsulated CNTs (CNT@meso-HA). The modification of CNTs by mesoporous HA leads to strong CNT-HA interfacial bonding, resulting in efficient load transfer between CNT and HA and improved mechanical properties of CNT/HA composites. More importantly, the mesoporous HA structure has a high specific surface area and large surface roughness that greatly promote the cell adhesion and proliferation, resulting in better biocompatibility and improved osteoblast viability (MC3T3-E1) compared to those fabricated by traditional methods. Therefore, the obtained CNT@meso-HA composites are expected to be promising materials for bone regeneration and implantation applications., (Copyright © 2017 Elsevier B.V. All rights reserved.)

There is a significant cost to mitigate the infection and inflammation associated with the implantable medical devices. The development of effective antibacterial and anti-inflammatory biomaterials with novel mechanism of action has become an urgent task. In this study, a supramolecular polymer hydrogel is synthesized by the copolymerization of N-acryloyl glycinamide and 1-vinyl-1,2,4-triazole in the absence of any chemical crosslinker. The hydrogel network is crosslinked through the hydrogen bond interactions between dual amide motifs in the side chain of N-acryloyl glycinamide. The prepared hydrogels demonstrate excellent mechanical properties-high tensile strength (≈1.2 MPa), large stretchability (≈1300%), and outstanding compressive strength (≈11 MPa) at swelling equilibrium state. A simulation study elaborates the changes of hydrogen bond interactions when 1-vinyl-1,2,4-triazole is introduced into the gel network. It is demonstrated that the introduction of 1-vinyl-1,2,4-triazole endowes the supramolecular hydrogels with self-repairability, thermoplasticity, and reprocessability over a lower temperature range for 3D printing of different shapes and patterns under simplified thermomelting extrusion condition. In addition, these hydrogels exhibit antimicrobial and anti-inflammatory activities, and in vitro cytotoxicity assay and histological staining following in vivo implantation confirm the biocompatibility of the hydrogel. These hydrogels with integrated multifunctions hold promising potential as an injectable biomaterial for treating degenerated soft supporting tissues., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Here, N-acetyl-d-glucosamine (GlcNAc), the monomer composing the second most abundant biopolymer, chitin, was efficiently converted into 5-hydroxymethylfurfural (5-HMF) using ionic liquid (IL) catalysts in a water/dimethyl sulfoxide (DMSO) mixture solvent. Various reaction parameters, including reaction temperature and time, DMSO/water mass ratios and catalyst dosage were optimized. A series of ILs with different structures were analyzed to explore their impact on GlcNAc conversion. The substrate scope was expanded from GlcNAc to d-glucosamine, chitin, chitosan and monosaccharides, although 5-HMF yields obtained from polymers and other monosaccharides were generally lower than those from GlcNAc. Moreover, the IL N-methylimidazolium hydrogen sulfate ([Hmim][HSO 4 ]) exhibited the best catalyst performance (64.6% yield) when GlcNAc was dehydrated in a DMSO/water mixture at 180 °C for 6 h without the addition of extra catalysts. To summarize, these results could provide knowledge essential to the production of valuable chemicals that are derived from renewable marine resources and benefit biofuel-related applications., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

We demonstrate in situ construction and characterization of supramolecular aggregates from chlorin p6 (Cp6) molecules in tumor cells. Fully deprotonated Cp6 molecules in neutral condition were partially protonated inside the acidic lysosomes of cells and significantly increased the hydrophobicity of them that resulted in simultaneous formation of J-type aggregates. Importantly, the formation of J-aggregates was fully characterized in artificial tissues by UV-vis, circular dichroism (CD) and transmission electron microscope (TEM) techniques. Compared to the monomers, the J-aggregates exhibited 55-fold enhanced thermal conversion efficiency (η) at the optimal excitation wavelength (690 nm). The remarkably increased heat effect contributed to the stronger photoacoustic (PA) signals, leading to at least 2 orders of magnitude increase of the tumor-to-normal tissue ratio (T/N), which was defined as the PA signal ratio between tumor site and surrounding normal tissue. We envision that this proof-of-concept study will open a new way to develop tumor environment-induced self-assembly for variable biomedical applications.

Nitrogen and boron co-doped carbon dots (BCNDs1-3) were prepared from three kinds of borate via a facile hydrothermal method. The as-prepared BCNDs did not shift with the change of excitation wavelength and possess good water dispersibility, strong fluorescence emission with high fluorescent quantum yield of 29.01%, 51.42%, 68.28%, respectively. Subsequently, these BCNDs were exploited as excellent Hg(2+) ion and 2,4,6-trinitrophenol (TNP) probe. The efficient selective detection of Hg(2+) can be attributed to non-radiative electron/hole recombination annihilation through an effective electron transfer process and the detection of TNP can be attributed to the fluorescence resonance energy transfer process (FRET). The results show that the BCNDs2 is the most sensitive fluorescence probe for Hg(2+) ions and TNP detection as low as Hg(2+) 7.3nM and TNP 0.35μM compared with BCNDs1 and BCNDs3. The as-prepared BCNDs possess the advantages of good selectivity, fast response and a broad linear detection. They were applied to sensing and imaging of human umbilical vein endothelial cells, showing low cytotoxicity and good biocompatibility., (Copyright © 2016. Published by Elsevier B.V.)

In situ construction of self-assemblies with unique property in living systems is a promising direction in the biomedical field. The noninvasive methods for significant enzyme activity in living cells or living subjects are imperative and meantime challenge tasks. The dynamic process of self-assembly of chlorophyll-based molecules in complex biological systems can be monitored by photoacoustic signals, which supports a noninvasive way to understand and quantitatively measure the activity of caspase-1. Furthermore, the activity of caspase-1 enables reflection of the bacterial infection in the early stage. Here, we present a biocompatible self-assembly from chlorophyll-peptide derivatives and first correlate the dynamic equilibrium with ratiometric photoacoustic signals. The intracellular equilibrium was managed by a bacterial infection precaution protein, i.e., caspase-1. This system offers a trial of noninvasive method to quantitative detection and real-time monitoring of bacterial infection in the early stage.

The membrane electro-bioreactor (MEBR) is a novel technology, it treats wastewater by combining membrane filtration, electrokinetic phenomena, and biological processes in one reactor. This paper aims to deal with hard biodegradation and high concentration phenol wastewater. Investigating the influence factors such as initial concentration, voltage, pH value, temperature and mixed liquor suspended solids (MLSS) toward phenol degradation process in electrocatalytic process and membrane bioreactor (MBR), and then apply the optimum conditions in the MEBR system. Results of continuous flow experiments demonstrated that MEBR increased the quality of the treated wastewater than conventional MBR. The above technics followed the zero-order reaction kinetics. The removal efficiency of MEBR was about 11.1% higher for phenol than the sum of the two individual processes. With the help of gas chromatography/mass spectrometry (GC-MS), this qualitative analysis looks at the degradation products of phenol generated in MEBR, through which 2,6-di-tert-butyl-p-benzoquinone was confirmed as the main degradation product., (Copyright © 2016. Published by Elsevier Ltd.)

A series of alkalized polysulfones (APSF) were synthesized by several chemical reactions (chloromethylation, quaternization and alkalization). Among these reactions, chloromethylation and quaternization are two key reactions and have been studied in detail regarding the optimization of both chloromethylation and quaternization. FTIR and (1)H NMR spectrum confirmed the successful preparation of chloromethylated polysulfone. The best IEC of APSF was obtained for 1.68meqg(-1) under reaction time of 10h and reaction temperature of 45°C. The APSF membrane as a heterogeneous catalyst for the transesterification of soybean oil with methanol was prepared through the method of solvent evaporation phase inversion. The effects of co-solvent types, mass ratios of soybean oil/co-solvent, water content and free fatty acids (FFAs) content in soybean oil on the conversions using the APSF membrane during transesterification were studied. The reusability of the APSF membrane and the kinetics of the reaction catalyzed by the APSF membrane were also investigated., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Probiotics have shown beneficial effects on health and prevention of diseases in humans. However, a concern for application of probiotics is the loss of viability during storage and gastrointestinal transit. The aim of this study was to develop an encapsulation system to preserve viability of probiotics when they are administrated orally and apply Lactobacillus rhamnosus GG (LGG) as a probiotic model to evaluate the effectiveness of this approach using in vitro and in vivo experiments. LGG was encapsulated in hydrogel beads prepared using pectin, a food grade polysaccharide, glucose, and calcium chloride, and lyophilized by freeze-drying. Encapsulated LGG was cultured in vitro under the condition that mimicked the physiological environment of the human gastrointestinal tract. Compared to non-encapsulated LGG, encapsulation increased tolerance of LGG in the acid condition, protected LGG from protease digestion, and improved shelf time when stored at the ambient condition, in regard of survivability and production of p40, a known LGG-derived protein involved in LGG's beneficial effects on intestinal homeostasis. To evaluate the effects of encapsulation on p40 production in vivo and prevention of intestinal inflammation by LGG, mice were gavaged with LGG containing beads and treated with dextran sulphate sodium (DSS) to induce intestinal injury and colitis. Compared to non-encapsulated LGG, encapsulated LGG enhanced more p40 production in mice, and exerted higher levels of effects on prevention of DSS-induced colonic injury and colitis and suppression of pro-inflammatory cytokine production. These data indicated that the encapsulation system developed in this study preserves viability of LGG in vitro and in vivo, leading to longer shelf time and enhancing the functions of LGG in the gastrointestinal tract. Thus, this encapsulation approach may have the potential application for improving efficacy of probiotics., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this work, an electrocatalytic membrane was prepared to degrade aqueous tetracycline (TC) using a carbon membrane coated with nano-TiO₂ via a sol-gel process. SEM, XRD, EDS, and XPS were used to characterize the composition and structure of the electrocatalytic membrane. The effect of operating conditions on the removal rate of tetracycline was investigated systematically. The results show that the chemical oxygen demand (COD) removal rate increased with increasing residence time while it decreased with increasing the initial concentration of tetracycline. Moreover, pH had little effect on the removal of tetracycline, and the electrocatalytic membrane could effectively remove tetracycline with initial concentration of 50 mg·L -1 (pH, 3.8-9.6). The 100% tetracycline and 87.8% COD removal rate could be achieved under the following operating conditions: tetracycline concentration of 50 mg·L -1 , current density of 1 mA·cm -2 , temperature of 25 °C, and residence time of 4.4 min. This study provides a new and feasible method for removing antibiotics in water with the synergistic effect of electrocatalytic oxidation and membrane separation. It is evident that there will be a broad market for the application of electrocatalytic membrane in the field of antibiotic wastewater treatment.

This article mainly deals with the following dilemmas, which affect oil sorption and sorbent preparation: (1) hydrophobization could facilitate oil sorption but has adverse impacts on emulsion sorption; (2) micropores of conventional oil sorbent do not exhibit effective emulsion sorption. To solve the above contradictions, hydrophilic and hydrophobic sites were fabricated onto polypropylene (PP) nonwoven through electron beam radiation and subsequent ring-opening reaction. Further, a similar structure without a hydrophilic site was constructed as comparison to verify the dilemmas. An oil sorption and emulsion adsorption experiment revealed that the PP nonwoven with specific hydrophilic and hydrophobic sites is more suitable for oil cleanup. The hydrophobic site preserved its hydrophobicity and sorption capacity, and the hydrophilic site on PP surface effectively increased the affinity between the hydrophilic interface of emulsion and sorbent. The overlapped and intertwined structures could provide spaces large enough to accommodate oil and emulsion. In addition, the oil and emulsion sorption behaviors were systematically analyzed. The PP nonwoven fabricated in this study may find practical application in the cleanup of oil spills and the removal of organic pollutants from water surfaces.

Calcium silicate particle containing mesoporous SiO2 (CaSiO3@SiO2) was grafted on the surface of non-woven polypropylene. The PP non-woven grafted calcium silicate containing mesoporous SiO2 (PP-g-CaSiO3@SiO2) was used as the matrix to prepare bovine serum albumin (BSA) molecularly imprinted polysiloxane (MIP) by using silanes as the functional monomers and BSA as the template. PP non-woven grafted BSA-imprinted polysiloxane (PP-g-CaSiO3@SiO2 MIP) was characterized by scanning electron microscope (SEM), Fourier transform infrared spectometry (FTIR) and drilling string compensator (DSC). Influence factors on the rebinding capacity of the MIP were investigated, such as grafting degree, the pH in treating CaSiO3 and the type and proportion of silanes. The rebinding properties of BSA on PP-g-CaSiO3@SiO2 and MIP were investigated under different conditions. The results indicated that the rebinding capacity of MIP for BSA reached 56.32 mg/g, which was 2.65 times of NIP. The non-woven polypropylene grafted BSA-imprinted polysiloxane could recognize the template protein and the selectivity factor (β) was above 2.4 when using ovalbumin, hemoglobin and γ-globulin as control proteins. The PP-g-CaSiO3@SiO2 MIP has favorable reusability., (Copyright © 2015 John Wiley & Sons, Ltd.)

A 2-D numerical kinetic model considering flow velocity and adsorption is developed to simulate the bio-electro tower reactor (BETR). This new model considers the adsorbed amount when equilibrium qe as transient variable, which is superior to the old pseudo-first-order and the pseudo-second-order model which regards qe as a constant. We did research on the intensifying effect of electric field upon heavy metal ions adsorption process. The calculation result matches well with the experimental data. BETR is a coupling technique whose mechanism is that outer electric field can enhance the mass transfer rate when the solute is metal ions. Two kinds of carriers, pottery ball and 3-dimensional electrode (3DE), were used to support the biofilm layer; and organic wastewater that contains Zn(2+) is selected as a sample to validate the model. The 3DE carriers can be polarized by outer electric field, but pottery ball cannot. It is found that Zn(2+) transfers faster in 3DE carriers than in pottery ball (insulation materials); and an intensifying coefficientη is introduced to describe this effect in BETR., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A bis-rhodamine based fluorescent probe R1 for naked-eye detection of Fe(3+) with enhanced sensitivity compared to a mono-rhodamine derivative that shows selectivity for Hg(2+), has been synthesized. The 1:1 stoichiometric structure of R1 and Fe(3+) is confirmed using a Job's plot estimation and density functional theory calculations. The reversibility of R1 is verified through its spectral response toward Fe(3+) and S(2-) titration experiments. Using Fe(3+) and S(2-) as chemical inputs and the fluorescence intensity signal as outputs, R1 can be utilized as an INHIBIT logic gate at molecular level. Fluorescent imaging for Fe(3+) in living HL-7702 cells have also been successfully performed., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Objective: To fabricate polymeric nanocomposites with excellent photoluminescence, magnetic properties, and stability in aqueous solutions, in order to improve specificity and sensitivity of cellular imaging under a magnetic field., Methods: Fluoridated Ln(3+)-doped HAP (Ln(3+)-HAP) NPs and iron oxides (IOs) can be encapsulated with biocompatible polymers via a modified solvent exaction/evaporation technique to prepare polymeric nanocomposites with fluoridated Ln(3+)-HAP/iron oxide. The nanocomposites were characterized for surface morphology, fluorescence spectra, magnetic properties and in vitro cytotoxicity. Magnetic targeted cellular imaging of such nanocomposites was also evaluated with confocal laser scanning microscope using A549 cells with or without magnetic field., Results: The fabricated nanocomposites showed good stability and excellent luminescent properties, as well as low in vitro cytotoxicity, indicating that the nanocomposites are suitable for biological applications. Nanocomposites under magnetic field achieved much higher cellular uptake via an energy-dependent pathway than those without magnetic field., Conclusion: The nanocomposites fabricated in this study will be a promising tool for magnetic targeted cellular imaging with improved specificity and enhanced selection.

A method of high-throughput determination, which is based on ultrasound-assisted liquid-phase microextraction, was developed to measure directly the partition coefficients of n-octanol-water. In ultrasound-assisted liquid-phase microextraction, ultrasonic energy can facilitate the mass transfer process of six or more microextractors simultaneously. Therefore, high-throughput determination of n-octanol-water partition coefficients can be performed favorably, and the equilibrium time of each microextractor can be decreased effectively. Several experimental parameters including ultrasonic power and frequency, centrifugation conditions, extractant volume and sample concentration were analyzed and optimized at 25°C. Under the optimum conditions, it only takes 2 min to reach extraction equilibrium, and the solutions of sample can be separated by centrifugation in 4 min. After centrifugation, the concentrations in n-octanol phases are analyzed with gas chromatography. The method was further evaluated with eight reference compounds and the findings demonstrated that this method is suitable to determine the partition coefficients of organic compounds accurately and quickly. Next, the method was exploited to measure the partition coefficients of n-octanol-water containing 20 organic compounds, which cover the [Formula: see text] values from 0.05 to 4.36, with comparatively low relative standard deviation (RSD) directly. The results of this study illustrated that the RSD (n = 6) was under 3%., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

This study investigates the influence of key biomass parameters on specific oxygen uptake rate (SOUR) in a sponge submerged membrane bioreactor (SSMBR) to develop mathematical models of biomass viability. Extra-cellular polymeric substances (EPS) were considered as a lumped parameter of bound EPS (bEPS) and soluble microbial products (SMP). Statistical analyses of experimental results indicate that the bEPS, SMP, mixed liquor suspended solids and volatile suspended solids (MLSS and MLVSS) have functional relationships with SOUR and their relative influence on SOUR was in the order of EPS>bEPS>SMP>MLVSS/MLSS. Based on correlations among biomass parameters and SOUR, two independent empirical models of biomass viability were developed. The models were validated using results of the SSMBR. However, further validation of the models for different operating conditions is suggested., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A novel molecularly imprinted electrochemical sensor based on Fe3O4 nanobeads immobilized on graphene (Fe3O4-MIP@RGO) has been developed for detecting 17β-estradiol (17β-E2) in water using reversible addition fragmentation chain transfer (RAFT) polymerization technique. 17β-E2 can be detected by this electrochemical sensor through the response current change before and after binding 17β-E2. The Fe3O4-MIP@RGO-based sensor amplifies the response current in differential pulse voltammetry measurement, allowing the detection limit reaching 0.819 nM in a wide linear range from 0.05 to 10 μM. Moreover, Fe3O4-MIP@RGO-based sensor exhibits high selectivity and sensitivity towards 17β-E2. This MIP electrochemical sensor has a promising potential in the detection of 17β-E2 in water., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The organosilane-functionalized carbon dots (SiCDs) were synthesized using citric acid with N-(b-aminoethyl)-g-aminopropyl methyldimethoxy silane (AEAPMS). The as-synthesized SiCDs were characterized by IR, TEM, XPS, NMR and fluorescence. The SiCDs showed a strong emission at 455 nm with excitation at 365 nm. The SiCDs exhibited analytical potential as sensing probes for quercetin (QCT) determination. pH effect, temperature effect, interferences, and analytical performance of the method were investigated. It suggested that SiCDs exhibited high sensitivity and selectivity toward QCT: the linear ranges of SiCDs were estimated to be 0-40 μM while the limit of detection (LOD) was calculated to be 79 nM., (Copyright © 2015. Published by Elsevier B.V.)

Organic-inorganic membranes were obtained by stepwise modification of poly(ethyleneterephthalate) track membrane with nanoparticles of zirconium hydrophosphate. The modifier was inserted inside pores of the polymer, a size of which is 0.33 μm. Inner active layer was formed by this manner. Evolution of morphology and functional properties of the membranes were investigated using methods of porosimetry, potentiometry and electron microscopy. The nanoparticles (4 to 10 nm) were found to form aggregates, which block pores of the polymer. Pores between the aggregates (4 to 8 nm) as well as considerable surface charge density provide significant transport numbers of counter ions (up to 0.86 for Na(+)). The materials were applied to baromembrane separation of corn distillery. It was found that precipitate is formed mainly inside the pores of the pristine membrane. In the case of the organic-inorganic material, the deposition occurs onto the outer surface and can be removed by mechanical way. Location of the active layer inside membranes protects it against damage.

This work provides a promising way to improve the hemocompatibility of PVDF membrane. An amphiphilic copolymer (PVDF-g-PACMO) having PVDF backbones and poly(N-acryloylmorpholine) (PACMO) side chains was synthesized via atom transfer radical polymerization (ATRP). It is found that the grafting degree of the PACMO increases linearly with the increase of ACMO concentration in the reaction solution. The PVDF-g-PACMO membrane was prepared via immersed phase inversion method. The structure and performances were evaluated by X-ray photoelectron spectroscopy, field emission scanning electron microscopy, water contact angle, and filtration experiment. The hemocompatibility of the membranes were preliminarily investigated by protein adsorption, platelet adhesion, anticoagulant evaluation and hemolysis test. The results indicate that the PVDF membrane functionalized by PACMO can suppress the protein adsorption and platelet adhesion, and shows an improved hemocompatibility., (© 2014 Wiley Periodicals, Inc.)

Poly(methacrylic acid)-MnO(OH)2/SiO2 core-shell microspheres were prepared by sol-gel hydrolysis of tetraethylorthosilicate (TEOS) in the presence of poly(methacrylic acid)-Mn(II) (PMAA-Mn(2+)) as template with ammonium hydroxide anion as catalyst and n-octadecyltrimethoxysilane (C18TMS) as pore-directing reagent. The PMAA-Mn(2+) core was prepared by incubation of Mn(2+) cations with PMAA microspheres via the coordination between carboxylate anion group on PMAA microsphere and Mn(2+) cations. During this process, the Mn(II) species were formed as white Mn(OH)2 precipitates at first, which were subsequently oxidized into brown MnO(OH)2 in air. The Mn2O3/mesoporous silica (Mn2O3/m-SiO2) double-shelled hollow microspheres (DSHMs) were prepared through calcination of the PMAA-MnO(OH)2/SiO2 core-shell microspheres at 600 °C for the selective removal of PMAA template and pore-directing organic component from C18TMS, during which the crystalline structure of DSHM was developed into Braunite-1Q via the reaction between Mn2O3 inner-shell and silica outer-shell by annealing the DSHMs under higher temperatures of 800 and 900 °C. The Mn2O3 hollow microspheres (HMs) were prepared through the selective removal of the silica layer from the DSHMs by sodium hydroxide aqueous solution, which exhibited structure integrity and good ethanol dispersity due to the presence of mesoporous structure., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The study mainly investigated the synergetic adsorption of hydrogen bonding and hydrophobic interaction. To simplify the adsorption driving forces and binding sites, the hydrophilic and hydrophobic microdomain was introduced onto polypropylene (PP) nonwoven. The amphiphilic structure was constructed for the adsorption of bisphenol A (BPA). A solvent shielding experiment was conducted to calculate the contributions of diverse interactions. Also, a specific structure without hydrophilic microdomain was constructed as comparison to determine the adsorption rate and quantify the diffusion behaviors. On the basis of double-exponential model, the adsorption process can be distinctly divided into three stages, namely film diffusion stage, intralayer diffusion stage, and dynamic equilibrium stage. The adsorption rate was dramatically improved due to the influence of hydrophilic microdomain and participation of hydrogen bonding adsorption. Discussions on adsorption priority were also proposed. The results of surface energy heterogeneity revealed that the hydrophilic microdomain or the hydrogen bonding site was occupied preferentially.

Fluorescent-magnetic iron oxide coated fluoridated HAp/Ln(3+) (Ln = Eu or Tb) nanocomposites were prepared. After transforming hydrophobic fluoridated HAp/Ln(3+) nanorods into hydrophilic ones, iron oxide particles were coated on their surface via thermal decomposition of Fe(acac)3. Fluorescent-magnetic nanocomposites developed in this study demonstrate excellent fluorescent-magnetic properties and prominent biocompatibility.

A bio-cathode microbial fuel cell (MFC) with tubular membrane was integrated to construct a microbial fuel cell-tubular membrane bioreactor (MFC-TMBR) system, in which the bio-cathode MFC was developed as a biosensor for COD real-time monitoring in TMBR and the performance was analyzed in terms of its current variation caused by operation parameters. With a constant anode potential, the effect of HRT demonstrated that higher rate of mass transport increased the response of the system. The system was further explored an inverse relationship between TMP and current peak by using EPS concentration under the different MLSS concentration. The sensor output had a linear relationship with COD up to 1000mg/L (regression coefficient, R(2)=0.97) and MLSS (regression coefficient, R(2)=0.94). The simple and compact bio-cathode MFC biosensor for TMBR using MFC-TMBR integrated system showed promising potential for direct and economical COD online monitoring, and provided an opportunity to widen the application of MFC-based biosensor., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

A facile one-pot approach is successfully developed to construct the stable Au nanochains with silica shell via self-assembly and classical Stöber process. The resulting Au chain@SiO2 nanoparticles holds great promise for serving as a safe, reusable, and high-performance photothermal agent against cancer., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Dynamic rheological behaviors of α-cellulose 1-ethyl-3-methylimidazolium chloride ([Emim]Cl)/dimethylsulfoxide (DMSO) solutions were investigated in a large range of cellulose concentrations (0.1-10 wt%) at 25°C. The overlap concentration c* and the entanglement concentration ce for cellulose in [Emim]Cl/DMSO were determined to be 0.5 wt% and 2.0 wt% respectively, and the exponents of the specific viscosity ηsp versus cellulose concentration c were determined as 1.1, 2.1 and 4.7 for dilute, semidilute unentangled and entangled regimes respectively, which were in accordance with the scaling prediction for neutral polymer in θ solvent. Under the same cellulose concentration, the complex viscosity η*, the reptation time τrep and the relaxation time of a segment between entanglements τe all decreased with increasing DMSO content in the solvent, while the number of entanglements of cellulose chains and the molar mass of an entanglement strand Me both remained unchanged., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

A novel kind of cell-like particles as temperature-responsive catalysts was presented in this paper. First, uniform α-Fe₂O₃shuttle-like nanoparticles were prepared by homogeneous hydrolysis. Then, these α-Fe₂O₃particles were coated by Au nanoparticles (AuNPs), SiO₂and poly (N-isopropylacrylamide) (PNIPAM), respectively. After the removal of SiO₂layer by etching with HF solution, the cell-like particles were prepared when the α-Fe₂O₃, AuNPs, and PNIPAM were as cell nucleus, catalysts, and cell membranes, respectively. These cell-like particles showed a novel temperature-responsively catalytic performance because the PNIPAM shell could change its hydrophilicity and swelling capacity under different temperature. When the temperature was 25°C, the yield of 4-aminophenol (4-AP) from 4-nitrophenol (4-NP) by reduction of NaBH₄was about 100% in 15 min, while the yield of 4-AP was about 90.5% in 40 min. when the temperature was 40°C.