This work reports a new protein-directed, hydrogen-bonded assembly strategy to organize proteins and organic linkers into robust hybrid frameworks. The pconjugated carboxylate linkers are feasible to be anchored on the peptide backbone of proteins through hydrogen-bonded interaction and then by

Target compounds 4a- n were obtained by the reaction of 1-substituted phenyl-3-methyl-5-substituted phenylthio-4-pyrazolaldoximes (3) with chloromethylated heterocyclic compounds (ClCH 2-R 3) under reflux conditions in ethanol. Subsequently, the oxidation of 4a- e with KMnO 4 in HOAc at room temperature afforded eight new compounds, 5a- h. The synthesized compounds were characterized by physical constants, and the structures of the title compounds were confirmed by IR, (1)H NMR, (13)C NMR, and elemental analysis. The bioassay revealed that the compounds possessed antiviral activities. It was found that title compounds 4a and 4g had the same inactivation effects against TMV (EC 50 = 58.7 and 65.3 microg/mL) as the commercial product Ningnanmycin (EC 50 = 52.7 microg/mL). To the best of our knowledge, this is the first report on the antiviral activity of pyrazole derivatives containing an oxime moiety.

Constructing inorganic-organic hybrids with superior properties in terms of water adsorption and activation will lead to catalysts with significantly enhanced electrocatalytic activity in the hydrogen evolution reaction (HER) in environmentally benign neutral media. Herein, we report SiO -polypyrrole (PPy) hybrid nanotubes supported on carbon fibers (CFs) (SiO /PPy NTs-CFs) as inexpensive and high-performance electrocatalysts for the HER in neutral media. Because of the strong electronic interactions between SiO and PPy, the SiO uniquely serves as the centers for water adsorption and activation, and accordingly promotes the HER. The metal-free SiO /PPy NTs-CFs displayed high catalytic activity in the HER in neutral media, such as a low onset potential and small Tafel slope, as well as excellent long-term durability.

Herein, we report the first example of using mesoporous hydrogen‐bonded organic frameworks (MHOFs) as the protecting scaffold to organize a biocatalytic cascade. The confined microenvironment of MHOFs has robust and large transport channels, allowing the efficient transport of a wide range of biocatalytic substrates. This new MHOF‐confined cascade system shows superior activity, extended scope of catalytic substrates, and ultrahigh stability that enables the operation of complex chemical transformations in a porous carrier. In addition, the advantages of MHOF‐confined cascades system for point‐of‐care biosensing are also demonstrated. This study highlights the advantages of HOFs as scaffold for multiple enzyme assemblies, which has huge potential for mimicking complex cellular transformation networks in a controllable manner.

A modified Solid-Phase Microextraction (SPME) device has been used as a passive sampler to determine the time-weighted average (TWA) concentration of volatile organic compounds (VOCs) in air. Unlike conventional sampling with SPME, in which the fiber is extended outside its needle housing, during TWA passive sampling, the fiber is retracted a known distance into its needle housing. The SPME passive sampler collects the VOCs by the mechanism of molecular diffusion and sorption on to a coated fiber as collection medium. This process has been shown to be described by Fick's first law of diffusion, whereby determination of the amounts of analytes accumulated over time enable measurement of the TWA concentration to which the sampler was exposed. A series of fibers, 100-microm poly(dimethylsiloxane), 65-microm poly(dimethylsiloxane)/divinylbenzene, and 75-microm Carboxen/poly(dimethylsiloxane), were tested for their "zero sink", face velocity, and response time behavior. Of the fibers tested, that coated with 75-microm Carboxen/poly(dimethylsiloxane) was found to be an excellent passive sampler for VOCs. TWA passive sampling with a SPME device was shown to be almost independent of face velocity and to be more tolerant of high and low analyte concentrations and long and short sampling times, because of the ease with which the diffusion path length could be changed. It was found that environmental conditions, e.g., temperature, pressure, relative humidity, and ozone, have little or no effect on sampling. The 75-microm Carboxen/poly(dimethylsiloxane) fiber can retain VOCs for up to two weeks without significant loss. When the SPME device was tested in the field and the results were compared with those from National Institute of Occupational Health and Safety method 1501, good agreement was obtained.

An in situ strategy to simultaneously boost oxygen reduction and oxygen evolution (ORR/OER) activities of commercial carbon textiles is reported and the direct use of such ubiquitous raw material as low‐cost, efficient, robust, self‐supporting, and bifunctional air electrodes in rechargeable Zn‐air batteries is demonstrated. This strategy not only furnishes carbon textiles with a large surface area and hierarchical meso‐microporosity, but also enables efficient dual‐doping of N and S into carbon skeletons while retaining high conductivity and stable monolithic structures. Thus, although original carbon textile has rather poor catalytic activity, the activated textiles without loading other active materials yield effective ORR/OER bifunctionality and stability with a much lower reversible overpotential (0.87 V) than those of Pt/C (1.10 V) and RuO2 (1.02 V) and many reported metal‐free bifunctional catalysts. Importantly, they can concurrently function as current collectors and as ORR/OER catalysts for rechargeable aqueous and flexible solid‐state Zn‐air batteries, showing excellent cell performance, long lifetime, and high flexibility.

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