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The ion-transfer (IT) experiments are reported at the water/neat 1,2-dichloroethane (DCE) interface for a wide class of hydrophilic ions, including metal cations, protons and some anions. The new mechanism of ion transfer involves transient interfacial ion pairing and shuttling of a hydrophilic ion across the mixed-solvent layer.

The crystal structures of native phosphatase of regenerating liver (PRL) -1 as well as the catalytically inactive mutant PRL-1/C104S in complex with sulfate are described. Structural and kinetic analyses place PRL-1 in the family of dual specificity phosphatases with closest structural similarity to the Cdc14 phosphatase and provide a molecular basis for catalytic activation of the PRL phosphatases.

A novel method to study electron-transfer (ET) reactions between ferrocene in 1,2-dichloroethane (DCE) and a redox couple of K3Fe(CN)6 and K4Fe(CN)6 in water is reported. The apparent heterogeneous rate constant for the ET reactions was obtained by fitting the experimental approach curves to the theoretical values.

A combination of steady-state voltammetry and scanning electrochemical microscopy is employed to study the electrochemistry of the individual molecules present in zeptoliter volumes. The volume and concentration of the solution is shown to highly change the number of redox molecules in the thin layer cell (TLC).

The first benzyl alkylation is shown for constructing the [sp.sup.3] C-C bond through Kumada coupling via Ni-catalyzed highly selective benzylic [sp.sup.3] C-O activation. The transformation has showed high efficiency and chemoselectivity and has offered new tools for assembling complex molecules.

The article explains the effects of trace amounts of water on the transfer of hydrophilic and hydrophobic ions to various low-polarity organic solvents. The hydrophobic ions are transferred to near organic solvents, whereas hydrophilic ions are only transferred to the water clusters.

A study reports electrochemical and angle-resolved X-ray photoelectron spectroscopy measurements of surface-bound porphyrazine monolayers in which the molecule-surface distance and molecular orientation of the porphyrazine are controlled through the design of the adsorbates. Results indicate that the shift in reduction potential upon surface binding is not a discontinuous function of the molecule-surface distance, but rather varies smoothly.

The possibility of electrochemical measurements at the nano-immiscible electrolyte solutions (ITIES) between an aqueous solution and a neat organic solvent is demonstrated. The transfers of strongly hydrated alkali metal cations from water to a less polar organic solvent, such as 1,2-dichloroethane (DCE), occur only in the presence of organic supporting electrolyte.

A new approach to investigate heterogeneous electron transfer (ET) reactions at an immiscible electrolyte solution (ITIES) is reported. Scanning electrochemical microscopy (SECM) with a three-electrode setup to investigate ET processes at an ITIES is employed to observe the Marcus inverted region for two totally different systems at a bare L/L interface.

Nd was used as the modifier to improve the NH3-selective catalytic reduction (SCR) performance of MnNOx catalyst used in NNOx abatement. The results of the activity test indicated that MnNdNOx-0.1 catalyst displayed remarkable catalytic activity and N2 selectivity in the temperature range of 50-300 °C. Characterization results proved the enhanced reducibility and the facilitated NH3 and NNOx adsorption over MnNdNOx-0.1 catalyst, accompanied by the existence of more Mn4+ and surface adsorbed oxygen species over its surface. The results of the in situ diffuse reflectance infrared Fourier transform study pointed out that the NH3-SCR reaction over the MnNdNOx-0.1 catalyst was mainly under the control of the Langmuir-Hinshelwood mechanism (≤100 °C); when the reaction temperature was over 200 °C, the Eley-Rideal mechanism was dominant. More adsorbed NNOx and NH3 species over the MnNdNOx-0.1 catalyst, along with the activation effect of Nd on the adsorbed reactants, had a facilitation impact on the SCR reaction process over the MnNdNOx-0.1 catalyst. [ABSTRACT FROM AUTHOR]

As the most straightforward synthetic strategy for cyclic polymers in theory, the traditional homodifunctional bimolecular ring-closure methods showed limited success for preparing pure cyclic polymers in practice even after several decades of development. A breakthrough was achieved in this paper to develop a successful homodifunctional bimolecular ring-closure method using a self-accelerating double strain-promoted azide-alkyne click reaction as the intermolecular and subsequent intramolecular coupling reactions. Because of the self-accelerating property of coupling reaction, this novel approach eliminated the usage of equimolar quantities between telechelic polymers and small molecule linkers, which was the prerequisite of traditional homodifunctional bimolecular ring-closure methods for pure cyclic polymers. More importantly, this approach could use an excess amount of small linkers to increase the intermolecular coupling reaction rate, further resulting in a significantly enhanced preparation efficiency of cyclic polymers. [ABSTRACT FROM AUTHOR]

A Rh(III)-catalyzed annulation between salicylaldehydes and diazo compounds with controllable chemoselectivity is described. AgNTf2 favored benzofurans via a tandem C-H activation/decarbonylation/annulation process, while AcOH led to chromones through a C-H activation/annulation pathway. The reaction exhibited good functional group tolerance and scalability. Moreover, only a single regioisomer of benzofuran was obtained due to the in situ decarbonylation orientation effect. [ABSTRACT FROM AUTHOR]

Reported herein is a Rh-catalyzed redox-neutral annulation of primary benzamides with diazo compounds, representing an efficient and economic protocol to isoquinolinones. The procedure exhibited good functional group tolerability, scalability, and regioselectivity, obviating the need for oxidants, and only environmentally benign N2 and H2O were released. Further utilization of the method provided an alternative route to functionalized isoquinolines. [ABSTRACT FROM AUTHOR]

A positivelycharged nanofiltration (NF) hollow fiber membranewith an antifouling feature has been fabricated and scaled up to pilotscale to treat colored wastewater from a dyestuff manufacturer withthe aid of the coagulation–flocculation (CF) process. An effectiveCF formulation, i.e., iron chloride/anionic polyacrylamide (IC/APAM)= 800/100 ppm, has been identified to treat the NF concentrate stream.The challenges of membrane fouling and processing concentrate streamscan be effectively managed by the integrated NF–CF process.The NF process is able to achieve 82% and 67% removal of color andchemical oxygen demand (COD) from the colored wastewater, respectively;while the CF process can remove 91% of color and 81% of COD from theNF concentrate stream. NF and CF were found to complement each other.The NF process alone always generates a concentrate stream, but itcan effectively reduce the wastewater volume. The CF processes areparticularly favorable for treating small volume concentrate streams.These advantages make the NF–CF process propitious for userslocated in land- or space-limited places and countries. [ABSTRACT FROM AUTHOR]

It has long been puzzling that water nanodroplets undergo simultaneously "supercooling" at freezing and "superheating" at melting. Recent progress (Sun et al. J. Phys. Chem. Lett.2013, 4, 2565, 3238) enables us to resolve this anomaly from the perspective of hydrogen bond (O:H-O) specific heat disparity. A superposition of the specific heat ?x(T) curves for the H-O bond (x = H) and the O:H nonbond (x = L) defines two intersecting temperatures that form the ice/quasi-solid/liquid phase boundaries. Molecular undercoordination (with fewer than four nearest neighbors in the bulk) stretches the ?H(T) curve by raising the Debye temperature TDH through H-O bond shortening and phonon stiffening. The ?H(T) stretching is coupled with the ?L(T) depressing because of the Coulomb repulsion between electron pairs on oxygen ions. The extent of dispersion varies with the size of a droplet that prefers a core-shell structure configuration?the bulk interior and the skin. Understandings may open an effective way of dealing with the thermodynamic behavior of water droplets and bubbles from the perspective of O:H-O bond cooperativity. [ABSTRACT FROM AUTHOR]

A mild and convenient protocol for direct synthesis of β-mannosides has been developed. Glycosylation of 4,6-O-benzylidene-protected mannosyi ortho-hexynyibenzoates with various alcohol acceptors catalyzed by gold(I) complex proceeded smoothly at 0 °C to room temperature and afforded the corresponding β-mannoside in high yield and satisfactory stereoselectivity. This reaction was applied to the total synthesis of acremomannolipin A and its analogue. [ABSTRACT FROM AUTHOR]

In this paper, we report the technical breakthroughs to synthesize outer-selective thin-film composite (TFC) hollow fiber membranes, which is in an urgent need for osmotic power generation with the pressure-retarded osmosis (PRO) process. In the first step, a defect-free thin-film composite membrane module is achieved by vacuum-assisted interfacial polymerization. The PRO performance is further enhanced by optimizing the support in terms of pore size and mechanical strength and the TFC layer with polydopamine coating and molecular engineering of the interfacial polymerization solution. The newly developed membranes can stand over 20 bar with a peak power density of 7.63 W/m2, which is equivalent to 13.72 W/m2 of its inner-selective hollow fiber counterpart with the same module size, packing density, and fiber dimensions. The study may provide insightful guidelines for optimizing the interfacial polymerization procedures and scaling up of the outer-selective TFC hollow fiber membrane modules for PRO power generation. [ABSTRACT FROM AUTHOR]

Dendrodolides A-M (1-13), 13 new 12-membered macrolides, were isolated from Dendrodochium sp., a fungus associated with the sea cucumber Holothuria nobilis Selenka, which was collected from the South China Sea. The structures of the dendrodolides were elucidated by means of detailed spectroscopic analysis and X-ray single-crystal diffraction. The absolute configurations were assigned using the modified Mosher method, exciton-coupled circular dichroism (ECCD), electronic solution and solid-state circular dichroism (ECD) supported by time-dependent density functional theory (TDDFT) ECD calculations, and X-ray analysis. A detailed conformational analysis of the 13 derivatives indicated that the conformation of the flexible macrolide ring plays a decisive role in their chiroptical properties. Thus, it is highly recommended to apply advanced levels of theory and to avoid simple comparison of ECD spectra to determine the absolute configurations of these derivatives. In an in vitro bioassay, compounds 1-5, 7-9, 11, and 12 exhibited different levels of growth inhibitory activity against SMMC-7721 and HCT116 cells. This is the first report of 12-membered macrolides from the fungus of the genus Dendrodochium. The coisolation of four pairs of epimers is extremely interesting and indicates the complexity of β-ketoreductase stereospecificity in the biosynthesis of enigmatic iterative fungal polyketides. [ABSTRACT FROM AUTHOR]