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Herein, we report polyphosphonate covalent organic frameworks (COFs) constructed via P-O-P linkages. The materials are synthesized via a single-step condensation reaction of the charge-assisted hydrogen-bonded organic framework, which is constructed from phenylphosphonic acid and 5,10,15,20-tetrakis[p-phenylphosphonic acid]porphyrin and is formed by simply heating its hydrogen-bonded precursor without using chemical reagents. Above 210 °C, it becomes an amorphous microporous polymeric structure due to the oligomerization of P-O-P bonds, which could be shown by constant-time solid-state double-quantum 31 P nuclear magnetic resonance experiments. The polyphosphonate COF exhibits good water and water vapor stability during the gas sorption measurements, and electrochemical stability in 0.5 M Na 2 SO 4 electrolyte in water. The reported family of COFs fills a significant gap in the literature by providing stable microporous COFs suitable for use in water and electrolytes. Additionally, we provide a sustainable synthesis route for the COF synthesis. The narrow pores of the COF effectively capture CO 2 ., (© 2024. The Author(s).)

A newly synthesized series of bimetallic CPM-37(Ni,Fe) metal-organic frameworks with different iron content (Ni/Fe ≈ 2, 1, 0.5, named CPM-37(Ni 2 Fe), CPM-37(NiFe) and CPM-37(NiFe 2 )) demonstrated high N 2 -based specific S BET surface areas of 2039, 1955, and 2378 m 2 g -1 for CPM-37(Ni 2 Fe), CPM-37(NiFe), and CPM-37(NiFe 2 ), having much higher values compared to the monometallic CPM-37(Ni) and CPM-37(Fe) with 87 and 368 m 2 g -1 only. It is rationalized that the mixed-metal nature of the materials increases the structural robustness due to the better charge balance at the coordination bonded cluster, which opens interesting application-oriented possibilities for mixed-metal CPM-37 and other less-stable MOFs. In this work, the CPM-37-derived α,β-Ni(OH) 2 , γ-NiO(OH), and, plausibly, γ-FeO(OH) phases obtained via decomposition in the alkaline medium demonstrated a potent electrocatalytic activity in the oxygen evolution reaction (OER). The ratio Ni : Fe ≈ 2 from CPM-37(Ni 2 Fe) showed the best OER activity with a small overpotential of 290 mV at 50 mA cm -2 , low Tafel slope of 39 mV dec -1 , and more stable OER performance compared to RuO 2 after 20 h chronopotentiometry at 50 mA cm -2 .

Certain types of face masks are highly efficient in protecting humans from bacterial and viral pathogens, and growing concerns with high safety, low cost, and wide market suitability have accelerated the replacement of reusable face masks with disposable ones during the last decades. However, wearing these masks creates countless problems associated with personnel comfort as well as more significant issues related to the cost of fabrication, the generation of medical waste, and environmental contaminants. In this work, we present a facile spray-pressing technique for the production of P-masks with a potential scale-up prospect by adding a graphene layer on one side of meltblown fabric and a functional layer on the other side. In principle, this technique could be easily integrated into the present automatic mask production process and the masks have self-cleaning and/or self-sterilizing properties when it is exposed to solar or simulated solar irradiation., Competing Interests: 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., (© 2023 The Authors.)

Metal-organic frameworks (MOFs) have been investigated with regard to the oxygen evolution reaction (OER) due to their structure diversity, high specific surface area, adjustable pore size, and abundant active sites. However, the poor conductivity of most MOFs restricts this application. Herein, through a facile one-step solvothermal method, the Ni-based pillared metal-organic framework [Ni 2 (BDC) 2 DABCO] (BDC = 1,4-benzenedicarboxylate, DABCO = 1,4-diazabicyclo[2.2.2]octane), its bimetallic nickel-iron form [Ni(Fe)(BDC) 2 DABCO], and their modified Ketjenblack (mKB) composites were synthesized and tested toward OER in an alkaline medium (KOH 1 mol L -1 ). A synergistic effect of the bimetallic nickel-iron MOF and the conductive mKB additive enhanced the catalytic activity of the MOF/mKB composites. All MOF/mKB composite samples (7, 14, 22, and 34 wt.% mKB) indicated much higher OER performances than the MOFs and mKB alone. The Ni-MOF/mKB14 composite (14 wt.% of mKB) demonstrated an overpotential of 294 mV at a current density of 10 mA cm -2 and a Tafel slope of 32 mV dec -1 , which is comparable with commercial RuO 2 , commonly used as a benchmark material for OER. The catalytic performance of Ni(Fe)MOF/mKB14 (0.57 wt.% Fe) was further improved to an overpotential of 279 mV at a current density of 10 mA cm -2 . The low Tafel slope of 25 mV dec -1 as well as a low reaction resistance due to the electrochemical impedance spectroscopy (EIS) measurement confirmed the excellent OER performance of the Ni(Fe)MOF/mKB14 composite. For practical applications, the Ni(Fe)MOF/mKB14 electrocatalyst was impregnated into commercial nickel foam (NF), where overpotentials of 247 and 291 mV at current densities of 10 and 50 mA cm -2 , respectively, were realized. The activity was maintained for 30 h at the applied current density of 50 mA cm -2 . More importantly, this work adds to the fundamental understanding of the in situ transformation of Ni(Fe)DMOF into OER-active α/β-Ni(OH) 2 , β/γ-NiOOH, and FeOOH with residual porosity inherited from the MOF structure, as seen by powder X-ray diffractometry and N 2 sorption analysis. Benefitting from the porosity structure of the MOF precursor, the nickel-iron catalysts outperformed the solely Ni-based catalysts due to their synergistic effects and exhibited superior catalytic activity and long-term stability in OER. In addition, by introducing mKB as a conductive carbon additive in the MOF structure, a homogeneous conductive network was constructed to improve the electronic conductivity of the MOF/mKB composites. The electrocatalytic system consisting of earth-abundant Ni and Fe metals only is attractive for the development of efficient, practical, and economical energy conversion materials for efficient OER activity.

Gas-phase infiltration of the carbonylchloridogold(I), Au(CO)Cl precursor into the pores of HKUST-1 ([Cu 3 (BTC) 2 (H 2 O) 2 ], Cu-BTC) SURMOFs (surface-mounted metal-organic frameworks; BTC = benzene-1,3,5-tricarboxylate) leads to Au(CO)Cl decomposition within the MOF through hydrolysis with the aqua ligands on Cu. Small Au x clusters with an average atom number of x ≈ 5 are formed in the medium-sized pores of the HKUST-1 matrix. These gold nanoclusters are homogeneously distributed and crystallographically ordered, which was supported by simulations of the powder X-ray diffractometric characterization. Au x @HKUST-1 was further characterized by scanning electron microscopy (SEM) and infrared reflection absorption (IRRA) as well as Raman spectroscopy, time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma optical emission spectroscopy (ICP-OES).

Single crystals of the new metal-organic framework (MOF) In-adc (HHUD-4) were obtained through the reaction of linear acetylenedicarboxylic acid (H 2 adc) with In(NO 3 ) 3 · x H 2 O as a racemic conglomerate in the chiral tetragonal space groups P 4 3 22 and P 4 1 22. Fundamentally different from other MOFs with linear linkers and trans -μ-OH-connected infinite {MO 6 } secondary building units as in the MIL-53-type, the linear adc 2- linker leads to the formation of cis -μ-OH connected {InO 6 } polyhedra, which have otherwise only been found before for V-shaped ligands, as in CAU-10-H. A far-reaching implication of this finding is the possibility that trans -μ-OH/straight MIL-53-type MOFs will have polymorphs of CAU-10-H cis -μ-OH/helical topology and vice versa . HHUD-4 is a microporous MOF with a BET surface area of up to 940 m 2 g -1 and a micropore volume of up to 0.39 cm 3 g -1 . Additionally, HHUD-4 features good adsorption uptakes of 3.77 mmol g -1 for CO 2 and 1.25 mmol g -1 for CH 4 at 273 K and 1 bar, respectively, and a high isosteric heat of adsorption of 11.4 kJ mol -1 for H 2 with a maximum uptake of 6.36 mmol g -1 at 77 K and 1 bar. Vapor sorption experiments for water and volatile organic compounds (VOCs) such as benzene, cyclohexane and n -hexane yielded uptake values of 135, 269, 116 and 205 mg g -1 , respectively, at 293 K. While HHUD-4 showed unremarkable results for water uptake and low stability for water, it exhibited good stability with steep VOC uptake steps at low relative pressures and a high selectivity of 17 for benzene/cyclohexane mixtures.

The metal-organic framework (MOF) [Zn(Isa-az-tmpz)]·~1-1.5 DMF with the novel T-shaped bifunctional linker 5-(2-(1,3,5-trimethyl-1H-pyrazol-4-yl)azo)isophthalate (Isa-az-tmpz) was obtained as a conglomerate of crystals with varying degrees of enantiomeric excess in the chiral tetragonal space groups P4 3 2 1 2 or P4 1 2 1 2. A topological analysis of the compound resulted in the rare 3,6T22 -topology, deviating from the expected rtl -topology, which has been found before in pyrazolate-isophthalate-functionalized MOFs using the supramolecular building layer (SBL) approach. 3,6T22 -[Zn(Isa-az-tmpz)]·~1-1.5 DMF is a potentially porous, three-dimensional structure with DMF molecules included in the corrugated channels along the a and b -axis of the as synthesized material. The small trigonal cross-section of about 6 × 4 Å (considering the van der Waals surface) prevents the access of N 2 and Ar under cryogenic conditions. After activation, only smaller H 2 (at 87 K) and CO 2 (at 195 K) are allowed for gas uptakes of 2 mmol g -1 and 5.4 mmol g -1 , respectively, in the ultramicroporous material, for which a BET surface area of 496 m 2 ·g -1 was calculated from CO 2 adsorption. Thermogravimetric analysis of the compound shows a thermal stability of up to 400 °C.

Objective: Transsignaling of interleukin (IL)-6 is a central pathway in the pathogenesis of disorders associated with chronic inflammation, such as Crohn disease, rheumatoid arthritis, and inflammatory colon cancer. Notably, IL-6 also represents an independent risk factor for coronary artery disease (CAD) in humans and is crucially involved in vascular inflammatory processes., Methods and Results: In the present study, we showed that treatment with a fusion protein of the natural IL-6 transsignaling inhibitor soluble glycoprotein 130 (sgp130) and IgG1-Fc (sgp130Fc) dramatically reduced atherosclerosis in hypercholesterolemic Ldlr(-/-) mice without affecting weight gain and serum lipid levels. Moreover, sgp130Fc treatment even led to a significant regression of advanced atherosclerosis. Mechanistically, endothelial activation and intimal smooth muscle cell infiltration were decreased in sgp130Fc-treated mice, resulting in a marked reduction of monocyte recruitment and subsequent atherosclerotic plaque progression. Of note, patients with CAD exhibited significantly lower plasma levels of endogenous sgp130, suggesting that a compromised counterbalancing of IL-6 transsignaling may contribute to atherogenesis in humans., Conclusions: These data clarify, for the first time, the critical involvement of, in particular, the transsignaling of IL-6 in CAD and warrant further investigation of sgp130Fc as a novel therapeutic for the treatment of CAD and related diseases.

It has been demonstrated that perfusion of myocardium with glutamic acid or tricarboxylic acid cycle intermediates during hypoxia or ischemia, improves cardiac function, increases ATP levels, and stimulates succinate production. In this study isolated adult rat heart cells were used to investigate the mechanism of anaerobic succinate formation and examine beneficial effects attributed to ATP generated by this pathway. Myocytes incubated for 60 min under hypoxic conditions showed a slight loss of ATP from an initial value of 21 +/- 1 nmol/mg protein, a decline of CP from 42 to 17 nmol/mg protein and a fourfold increase in lactic acid production to 1.8 +/- 0.2 mumol/mg protein/h. These metabolite contents were not altered by the addition of malate and 2-oxoglutarate to the incubation medium nor were differences in cell viability observed; however, succinate release was substantially accelerated to 241 +/- 53 nmol/mg protein. Incubation of cells with [U-14C]malate or [2-U-14C]oxoglutarate indicates that succinate is formed directly from malate but not from 2-oxoglutarate. Moreover, anaerobic succinate formation was rotenone sensitive. We conclude that malate reduction to succinate occurs via the reverse action of succinate dehydrogenase in a coupled reaction where NADH is oxidized (and FAD reduced) and ADP is phosphorylated. Furthermore, by transaminating with aspartate to produce oxaloacetate, 2-oxoglutarate stimulates cytosolic malic dehydrogenase activity, whereby malate is formed and NADH is oxidized. In the form of malate, reducing equivalents and substrate are transported into the mitochondria where they are utilized for succinate synthesis.

The main product of AA conversion by BAEC is PGI2. Other PGs were synthesized by confluent cells only in traces with exception of a HHT-like compound which has still to be characterized in more details. A significant release of HETE was only detected when BAEC were destroyed. Under these conditions about 1 pmole/10(5) cells 15- and 12 HETE were released by BAEC. Taken into account the amounts of HETE produced by endothelial cells as well as the partially contradictory activities of 12- and 15-HETE we suggest that an acclerated lipoxygenase activity reflects a lesion of endothelium, but is of minor physiological relevance as compared to the generation of HETE and other eicosanoids by blood cells.