There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Titanium Dioxide Nanomaterials: Synthesis, Properties, Modifications, and Applications

Metal-organic frameworks (MOFs) are an emerging class of porous materials with potential applications in gas storage, separations, catalysis, and chemical sensing. Despite numerous advantages, applications of many MOFs are ultimately limited by their stability under harsh conditions. Herein, the recent advances in the field of stable MOFs, covering the fundamental mechanisms of MOF stability, design, and synthesis of stable MOF architectures, and their latest applications are reviewed. First, key factors that affect MOF stability under certain chemical environments are introduced to guide the design of robust structures. This is followed by a short review of synthetic strategies of stable MOFs including modulated synthesis and postsynthetic modifications. Based on the fundamentals of MOF stability, stable MOFs are classified into two categories: high-valency metal-carboxylate frameworks and low-valency metal-azolate frameworks. Along this line, some representative stable MOFs are introduced, their structures are described, and their properties are briefly discussed. The expanded applications of stable MOFs in Lewis/Bronsted acid catalysis, redox catalysis, photocatalysis, electrocatalysis, gas storage, and sensing are highlighted. Overall, this review is expected to guide the design of stable MOFs by providing insights into existing structures, which could lead to the discovery and development of more advanced functional materials.

Stable Metal-Organic Frameworks: Design, Synthesis, and Applications.

http://csmres.co.uk/cs.public.upd/article-downloads/lynch.pdf

Protein-nanoparticle interactions

Atmospheric water is a resource equivalent to ~10% of all fresh water in lakes on Earth. However, an efficient process for capturing and delivering water from air, especially at low humidity levels (down to 20%), has not been developed. We report the design and demonstration of a device based on a porous metal-organic framework {MOF-801, [Zr6O4(OH)4(fumarate)6]} that captures water from the atmosphere at ambient conditions by using low-grade heat from natural sunlight at a flux of less than 1 sun (1 kilowatt per square meter). This device is capable of harvesting 2.8 liters of water per kilogram of MOF daily at relative humidity levels as low as 20% and requires no additional input of energy.

https://science.sciencemag.org/content/sci/early/2017/04/12/science.aam8743.full.pdf

Water harvesting from air with metal-organic frameworks powered by natural sunlight

Structural influence of hydrotalcite on Pd dispersion and phenol hydrogenation

In this contribution, we report studies on nonspecific protein−DNA interactions of an enzyme protein bovine pancreatic α-chymotrypsin (CHT) with genomic DNA (from salmon testes) using two biologically common fluorescent probes:  1-anilinonaphthalene-8-sulfonate (ANS) and 2,6-p-toluidinonaphthalene sulfonate (TNS). TNS molecules that are nonspecifically bound to positively charged basic residues at the surface sites, not in the hydrophobic cavities of the protein, are preferentially displaced upon complexation of TNS-labeled CHT with DNA. The time-resolved fluorescence anisotropy of TNS molecules bound to hydrophobic cavities/clefts of CHT reveals that global tumbling motion of the protein is almost frozen in the protein−DNA complex. A control study on TNS-labeled human serum albumin (HSA) upon interaction with DNA clearly indicates that the ligands in the deep pockets of the protein cannot be displaced by interaction with DNA. We have also found that ANS, which binds to a specific surface site of CHT, is ...

Nonspecific Protein−DNA Interactions: Complexation of α-Chymotrypsin with a Genomic DNA

Picosecond to nanosecond reorganization of water in AOT/lecithin mixed reverse micelles of different morphology

A water-harvesting system can operate with a material that can take up and release water with minimum energy requirements and powered by low-grade energy sources, such as sunlight, in order to potentially allow its deployment into households, especially those located in sunny regions. A water-harvesting method and system can include vapor adsorption using a porous metal-organic framework. In certain embodiments, the porous metal-organic framework can include metal-organic framework in ambient air with low relative humidity, typical of the levels found in most dry regions of the world.

Sorption-based atmospheric water harvesting device

Vanadia and silica-supported vanadia have been characterized by XRD, ESR and chemisorption of oxygen at low temperature (COLT) to assess the nature of the vanadia dispersion on the support. Aniline alkylation studies on the effect of temperature and contact time on the conversion and selectivity of the products reveal that supported vanadia is significantly more active than vanadia and SiO 2 . The alkylation reaction proceeds through consecutive formation of secondary, tertiary and C-alkylated anilines. Reaction conditions can be favourably modified to get selectively N-ethylaniline over vanadia-silica. An attempt has been made to correlate dispersion and catalytic activity with the active species.

Shankar Narayanan

Papers

Structural influence of hydrotalcite on Pd dispersion and phenol hydrogenation

Nonspecific Protein−DNA Interactions: Complexation of α-Chymotrypsin with a Genomic DNA

Picosecond to nanosecond reorganization of water in AOT/lecithin mixed reverse micelles of different morphology

Sorption-based atmospheric water harvesting device

Characterization and aniline alkylation activity of vanadia and silica-supported vanadia catalysts