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Water treatment through interface photothermal conversion using solar energy is a sustainable strategy for freshwater supply. Because the preparation method of highly efficient photothermal conversion materials with commercial value is the only way for the industrialization of solar steam generation, the preparation method and the rational design of photothermal materials are particularly important. In this work, the high-efficiency photothermal conversion material MXene nanosheets and low thermal conductivity SiO2 were coated on a hydrophilic poly-(tetrafluoroethylene) (HPTFE) membrane by a commercial continuous spraying system to produce a SiO2/MXene/HPTFE Janus membrane. They possess excellent mechanical properties, high stability, and 93.0% light absorption. The prepared evaporator can be used for water treatment with a photothermal evaporation rate of 1.53 kg m–2 h–1, achieving a uniform and effective 85.6% solar thermal conversion efficiency, which is superior to most reported work. The removal rate of wastewater and organic pollutants can reach 99.9%. At the same time, the two-dimensional Janus membrane has excellent salt resistance and self-cleaning ability, making it easy to store and transport. It is also used to build sensor systems. The sensor has an excellent light response and can accurately measure solar radiation density and temperature in a short time. Therefore, the use of commercial spraying systems provides a cost-effective and energy-saving strategy for photothermal evaporators and sensors to reduce the use of photothermal materials, achieve higher photothermal evaporation rates, and expand the application direction of photothermal materials. [ABSTRACT FROM AUTHOR]

This paper focuses on identifying structural features responsible for resolution of heavy isotope coded peptides during reversed-phase chromatography. This was achieved by using labeled coding agents that varied in structure, number of deuterium atoms, placement of deuterium in the coding agent, and the functional group targeted by the reagent. Six coding agents were examined. Deuterated versions of the coding agents studied included succinic anhydride-[sup.2][H.sub.4], acetic acid 2,5-dioxopyrrolidin-1-yl ester-[sup.2][H.sub.3], propionic acid 2,5-dioxopyrrolidin-1-yl ester-[sup.2][H.sub.5], pentanoic acid 2,5-dioxopyrrolidin-1-yl ester-[sup.2][H.sub.9], [3-(2,5-dioxopyrrolidin-1-yloxycarbonyl)-propyl]- trimethylammonium chloride-[sup.2][H.sub.9], and the commercial ICAT-[sup.2][H.sub.8] reagent. It was found that these labeling agents vary widely in both their absolute and relative contribution to the chromatographic isotope effect. Relative effects were evaluated by normalizing resolution for the number of deuterium atoms in the derivatized peptide. The single, most dominant effect was the placement of deuterium atoms relative to hydrophilic functional groups in the coding agent. It was concluded that the probability of a deuterium atom interacting with the stationary phase of a reversed-phase chromatography (RPC) column and impacting resolution is greatly diminished by placing it adjacent to a hydrophilic group, as explained by solvophobic theory. But peptide size and coding agent size were also seen to correlate inversely with the magnitude of the isotope effect. This effect was explained as being due to the relative size of the coding agent versus that of the coding agent-peptide conjugate.

Tris(hydroxymethyl)aminomethane (Tris) is grafted onto the surface of a [Ni.sub.6]-substituted polyoxotungstate formed in situ to generate a three-connected polyoxometalate building block. The cooperative assembly of Tris functionalized three-connected building blocks and rigid 1,3,5-benzenetricarboxylate has provided an unprecedented cubic polyoxometalate-organic molecular cage with high thermal and hydrothermal stability.

A bifunctional thiourea-tertiary amine-catalyzed asymmetric hydroxymethylation of 3-substituted oxinoles is developed by using paraformaldehyde as the C1 unit. The major feature of this approach has employed the paraformaldehyde as a hydroxymethylation C1 unit, which is activated by chiral bifunctional thiourea organocatalysts.

A new short approach to (--)-lepadins A--C has been developed based on a stereocontrolled Diels--Alder reaction employing a chiral dienophile. With this approach, (--)-lepadin B is synthesized from 5-deoxy-d-ribose in 13 steps with 14.8% overall yield. The cis-decahydroquinoline core containing five stereocenters could be rapidly constructed via stereoselective cycloaddition and subsequent five-step one-pot hydrogenation--cyclization. [ABSTRACT FROM AUTHOR]

A new method for fabrication of thin film nanofibrous composite (TFNC) ultrafiltration (UF) membrane consisting of an ultrathin poly(acrylonitrile-co-acrylic acid) (PAN-AA) barrier layer based on a polyacrylonitrile (PAN) nanofibrous support layer was proposed in this study. First, a thin PAN-AA nanofibrous layer was electrospun and deposited on a thicker PAN nanofibrous substrate. Then, the as-prepared PAN-AA nanofibers were swollen in the alkaline buffer solution and merged imperceptibly as an integrated nonporous hydrogel layer on the PAN substrate. The PAN-AA hydrogel layer was cross-linked with different bivalent metal cations (Ca2+, Mg2+) to form an ultrathin barrier layer, of which the thickness and porosity were optimized by controlling the depositing time of PAN-AA nanofibers and pH value of buffer solution. Proteins with different molecular weights were used to evaluate the ultrafiltration performance of the resultant composite membranes. Due to its hydrophilic and negative charged barrier layer, the PAN-AA-Mg and PAN-AA-Ca TFNC UF composite membranes exhibited excellent permeate flux (221.2 and 219.2 L/m² h) and rejection efficiency (97.8% and 95.6%) for bovine serum albumin (BSA) aqueous solution (1 g/L) at 0.3 MPa. The PAN-AA TFNC UF membranes could be used to retain solutes, of which the radius was larger than 4.6 nm. [ABSTRACT FROM AUTHOR]