Metal-organic frameworks (MOFs) have been recognized as compelling platforms for the development of miscellaneous applications because of their structural diversity and functional tunability. Here, we propose that the electrocatalytic properties could be well modified by incorporating missing linkers into the MOF. Theoretical calculations suggest the electronic structure of MOFs can be tuned by introducing missing linkers, which improves oxygen evolution reaction (OER) performance of the MOF. Inspired by these aspects, we introduced various missing linkers into a layered-pillared MOF Co2(OH)2(C8H4O4) (termed as CoBDC) to prepare missing-linker MOFs. Transmission electron microscope and synchrotron X-ray measurements confirmed that the missing linkers in the MOF could be introduced and well controlled by our strategy. The self-supported MOF nanoarrays with missing linkers of carboxyferrocene exhibit excellent OER performance with ultralow overpotential of 241 mV at 100 mA cm−2. This work opens a new prospect to develop efficient MOF-based electrocatalysts by introducing missing linkers.

A bacteriophage cocktail (designated ECP-100) containing three Myoviridae phages lytic for Escherichia coli O157:H7 was examined for its ability to reduce experimental contamination of hard surfaces (glass coverslips and gypsum boards), tomato, spinach, broccoli, and ground beef by three virulent strains of the bacterium. The hard surfaces and foods contaminated by a mixture of three E. coli O157:H7 strains were treated with ECP-100 (test samples) or sterile phosphate-buffered saline buffer (control samples), and the efficacy of phage treatment was evaluated by comparing the number of viable E. coli organisms recovered from the test and control samples. Treatments (5 min) with the ECP-100 preparation containing three different concentrations of phages (10 10 , 10 9 , and 10 8 PFU/ml) resulted in statistically significant reductions (P ‫؍‬ <0.05) of 99.99%, 98%, and 94%, respectively, in the number of E. coli O157:H7 organisms recovered from the glass coverslips. Similar treatments resulted in reductions of 100%, 95%, and 85%, respectively, in the number of E. coli O157:H7 organisms recovered from the gypsum board surfaces; the reductions caused by the two most concentrated phage preparations were statistically significant. Treatment with the least concentrated preparation that elicited significantly less contamination of the hard surfaces (i.e., 10 9 PFU/ml) also significantly reduced the number of viable E. coli O157:H7 organisms on the four food samples. The observed reductions ranged from 94% (at 120 ؎ 4 h posttreatment of tomato samples) to 100% (at 24 ؎ 4 h posttreatment of spinach samples). The data suggest that naturally occurring bacteriophages may be useful for reducing contamination of various hard surfaces, fruits, vegetables, and ground beef by E. coli O157:H7.

Above-room-temperature polar magnets are of interest due to their practical applications in spintronics. Here we present a strategy to design high-temperature polar magnetic oxides in the corundum-derived A2BB'O6 family, exemplified by the non-centrosymmetric (R3) Ni3TeO6-type Mn(2+)2Fe(3+)Mo(5+)O6, which shows strong ferrimagnetic ordering with TC = 337 K and demonstrates structural polarization without any ions with (n-1)d(10)ns(0), d(0), or stereoactive lone-pair electrons. Density functional theory calculations confirm the experimental results and suggest that the energy of the magnetically ordered structure, based on the Ni3TeO6 prototype, is significantly lower than that of any related structure, and accounts for the spontaneous polarization (68 μC cm(-2)) and non-centrosymmetry confirmed directly by second harmonic generation. These results motivate new directions in the search for practical magnetoelectric/multiferroic materials.

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A cocktail of six lytic bacteriophages, SalmoFresh™, significantly (p < 0.05) reduced the number of surface-applied Salmonella Kentucky and Brandenburg from stainless steel and glass surfaces by > 99% (2.1–4.3 log). Both strains were susceptible to SalmoFresh™ in the spot-test assay. Conversely, SalmoFresh™ was unable to reduce surface contamination with a Salmonella Paratyphi B strain that was not susceptible to the phage cocktail in the spot-test assay. However, by replacing two SalmoFresh™ component phages with two new phages capable of lysing the Paratyphi B strain in the spot-test assay, the target range of the cocktail was shifted to include the Salmonella Paratyphi B strain. The modified cocktail, SalmoLyse™, was able to significantly (p < 0.05) reduce surface contamination of the Paratyphi B strain by > 99% (2.1–4.1 log). The data show that both phage cocktails were effective in significantly reducing the levels of Salmonella on hard surfaces, provided the contaminating strains were susceptible in the spot-test (i.e., spot-test susceptibility was indicative of efficacy in subsequent surface decontamination studies). The data also support the concept that phage preparations can be customized to meet the desired antibacterial application.