Oxygen consumption of desert pupfish at ecologically relevant temperatures suggests a significant role for anaerobic metabolism.

Oxygen consumption is oftentimes used as a proxy for metabolic rate. However, pupfish acclimated to ecologically relevant temperatures may employ extended periods of anaerobism despite the availability of oxygen-a process we called paradoxical anaerobism. In this study, we evaluated data from pupfish exhibiting stable oxygen consumption.

The rotational dynamics of H adsorbed in covalent organic frameworks.

A combined inelastic neutron scattering (INS) and theoretical study was carried out on H adsorbed in two covalent organic framework (COF) materials: COF-1 and COF-102. These COFs are synthesized from self-condensation reactions of 1,4-benzenediboronic acid (BDBA) and tetra(4-(dihydroxy)borylphenyl)methane (TBPM) molecules, respectively. Molecular simulations of H adsorption in COF-1 revealed that the H molecules occupy the region between two eclipsed layers of the COF.

Exceptional ammonia uptake by a covalent organic framework.

Covalent organic frameworks (COFs) are porous crystalline materials composed of light elements linked by strong covalent bonds. A number of these materials contain a high density of Lewis acid boron sites that can strongly interact with Lewis basic guests, which makes them ideal for the storage of corrosive chemicals such as ammonia. We found that a member of the covalent organic framework family, COF-10, shows the highest uptake capacity (15 mol kg⁻¹, 298 K, 1 bar) of any porous material, including microporous 13X zeolite (9 mol kg⁻¹), Amberlyst 15 (11 mol kg⁻¹) and mesoporous silica, MCM-41 (7.

A crystalline imine-linked 3-D porous covalent organic framework.

A new crystalline porous three-dimensional covalent organic framework, termed COF-300, has been synthesized and structurally characterized. Tetrahedral tetra-(4-anilyl)-methane and linear terephthaldehyde building blocks were condensed to form imine linkages in a material whose X-ray crystal structure shows five independent diamond frameworks. Despite the interpenetration, the structure has pores of 7.

Reticular synthesis of covalent organic borosilicate frameworks.

This paper reports the synthesis and characterization of a new crystalline 3D covalent organic framework, COF-202: [C(C6H4)4]3[B3O6 (tBuSi)2]4, formed from condensation of a divergent boronic acid, tetra(4-dihydroxyborylphenyl)methane, and tert-butylsilane triol, tBuSi(OH)3. This framework is constructed through strong covalent bonds (Si-O, B-O) that link triangular and tetrahedral building units to form a structure based on the carbon nitride topology. COF-202 demonstrates high thermal stability, low density, and high porosity with a surface area of 2690 m2 g-1.

Designed synthesis of 3D covalent organic frameworks.

Three-dimensional covalent organic frameworks (3D COFs) were synthesized by targeting two nets based on triangular and tetrahedral nodes: ctn and bor. The respective 3D COFs were synthesized as crystalline solids by condensation reactions of tetrahedral tetra(4-dihydroxyborylphenyl) methane or tetra(4-dihydroxyborylphenyl)silane and by co-condensation of triangular 2,3,6,7,10,11-hexahydroxytriphenylene. Because these materials are entirely constructed from strong covalent bonds (C-C, C-O, C-B, and B-O), they have high thermal stabilities (400 degrees to 500 degrees C), and they also have high surface areas (3472 and 4210 square meters per gram for COF-102 and COF-103, respectively) and extremely low densities (0.