Additive manufacturing of 3D flow-focusing millifluidics for the production of curable microdroplets.

Microfluidics plays a crucial role in the generation of mono-sized microdroplet emulsions. Traditional glass microfluidic chips typically lack versatility in generating curable droplets of arbitrary liquids due to the inherent hydrophilic nature of glass and to fabrication constraints. To overcome this, we designed a microdroplet generator with 3D flow-focusing capabilities that can be 3D-printed.

Helical polyamines.

Polymer microstructures rely on tacticity, yet exploration in polyamines has focused predominantly on atactic polymers. We introduce a method to synthesize a diverse library of and -cyanobenzenesulfonyl-activated-methyl aziridines using , , and racemic alaninol. Living anionic ring-opening polymerization of racemic sulfonyl aziridines yields soluble polymers, while enantiomerically-pure sulfonyl aziridines follow a dispersion polymerization with complete monomer conversion giving access to stereoblock copolymers.

Temperature promotes selectivity during electrochemical CO reduction on NiO:SnO nanofibers.

Electrolyzers operate over a range of temperatures; hence, it is crucial to design electrocatalysts that do not compromise the product distribution unless temperature can promote selectivity. This work reports a synthetic approach based on electrospinning to produce NiO:SnO nanofibers (NFs) for selectively reducing CO to formate above room temperature. The NFs comprise compact but disjoined NiO and SnO nanocrystals identified with STEM.

Correction: From the Birkeland-Eyde process towards energy-efficient plasma-based NO synthesis: a techno-economic analysis.

[This corrects the article DOI: 10.1039/D0EE03763J.].

Disorder to order: how halide mixing in MAPbIBr perovskites restricts MA dynamics.

Mixed-halide lead perovskites are of particular interest for the design of tandem solar cells currently reaching record efficiencies. While halide phase segregation upon illumination of mixed perovskites is extensively studied, the effect of halide disorder on A cation dynamics is not well understood, despite its importance for charge carrier diffusion and lifetime. Here, we study the methylammonium (MA) reorientational dynamics in mixed halide MAPbIBr perovskites by a combined approach of experimental solid-state NMR spectroscopy and molecular dynamics (MD) simulations based on machine-learning force-fields (MLFF).

Kinetic model for the dehydration of xylose to furfural from a boronate diester precursor.

A comprehensive kinetic model describes the dehydration of xylose starting from the boronate diester-protected xylose (PBAX). The model incorporates (de)esterification of PBAX, partitioning, and xylose dehydration, and aims to evaluate the effects of the solvent system on these steps. The model explores the effect of the water contents in monophasic solvent systems, and that of ionic strength and mixing in biphasic aqueous-organic systems.

Identification of two-dimensional copper signatures in human blood for bladder cancer with machine learning.

Currently, almost all available cancer biomarkers are based on concentrations of compounds, often suffering from low sensitivity, poor specificity, and false positive or negative results. The stable isotopic composition of elements provides a different dimension from the concentration and has been widely used as a tracer in geochemistry. In health research, stable isotopic analysis has also shown potential as a new diagnostic/prognostic tool, which is still in the nascent stage.

From the Birkeland-Eyde process towards energy-efficient plasma-based NO synthesis: a techno-economic analysis.

Plasma-based NO synthesis the Birkeland-Eyde process was one of the first industrial nitrogen fixation methods. However, this technology never played a dominant role for nitrogen fixation, due to the invention of the Haber-Bosch process. Recently, nitrogen fixation by plasma technology has gained significant interest again, due to the emergence of low cost, renewable electricity.

Simultaneous heteroepitaxial growth of SrO (001) and SrO (111) during strontium-assisted deoxidation of the Si (001) surface.

Epitaxial integration of transition-metal oxides with silicon brings a variety of functional properties to the well-established platform of electronic components. In this process, deoxidation and passivation of the silicon surface are one of the most important steps, which in our study were controlled by an ultra-thin layer of SrO and monitored by using transmission electron microscopy (TEM), electron energy-loss spectroscopy (EELS), synchrotron X-ray diffraction (XRD) and reflection high energy electron diffraction (RHEED) methods. Results revealed that an insufficient amount of SrO leads to uneven deoxidation of the silicon surface formation of pits and islands, whereas the composition of the as-formed heterostructure gradually changes from strontium silicide at the interface with silicon, to strontium silicate and SrO in the topmost layer.

Recruitment of receptors at supported lipid bilayers promoted by the multivalent binding of ligand-modified unilamellar vesicles.

The development of model systems that mimic biological interactions and allow the control of both receptor and ligand densities, is essential for a better understanding of biomolecular processes, such as the recruitment of receptors at interfaces, at the molecular level. Here we report a model system based on supported lipid bilayers (SLBs) for the investigation of the clustering of receptors at their interface. Biotinylated SLBs, used as cell membrane mimics, were functionalized with streptavidin (SAv), used here as receptor.

Correction: Influenza as a molecular walker.

[This corrects the article DOI: 10.1039/C9SC05149J.].

Evaluation of two aza-crown ether-based multiple diglycolamide-containing ligands for complexation with the tetravalent actinide ions Np and Pu: extraction and DFT studies.

Two multiple diglycolamide (DGA)-containing extractants where the DGA arms are tethered to the nitrogen atoms of two aza-crown ether scaffolds, a 9-membered aza-crown ether containing three 'N' atoms (L) and a 12-membered aza-crown ether containing four 'N' atoms (L), were evaluated for the extraction of the tetravalent actinide ions Np and Pu. The tripodal ligand with three DGA arms (L) was relatively inferior in its metal ion extraction properties as compared to the tetrapodal ligand with four DGA arms (L) and Pu ion was better extracted than Np ion with both the ligands. A solvation extraction mechanism, where species of the type ML(NO) are extracted, was found to be operative for both the ligands involving both the tetravalent actinide ions.

Maskless Spatioselective Functionalization of Silicon Nanowires.

Spatioselective functionalization of silicon nanowires was achieved without using a masking material. The designed process combines metal-assisted chemical etching (MACE) to fabricate silicon nanowires and hydrosilylation to form molecular monolayers. After MACE, a monolayer was formed on the exposed nanowire surfaces.

Atomic force microscopy of confined liquids using the thermal bending fluctuations of the cantilever.

We use atomic force microscopy to measure the distance-dependent solvation forces and the dissipation across liquid films of octamethylcyclotetrasiloxane (OMCTS) confined between a silicon tip and a highly oriented pyrolytic graphite substrate without active excitation of the cantilever. By analyzing the thermal bending fluctuations, we minimize possible nonlinearities of the tip-substrate interaction due to finite excitation amplitudes because these fluctuations are smaller than the typical 1 Å, which is much smaller than the characteristic interaction length. Moreover, we avoid the need to determine the phase lag between cantilever excitation and response, which suffers from complications due to hydrodynamic coupling between cantilever and fluid.

Integrated mechano-optical hydrogen gas sensor using cantilever bending readout with a Si3N4 grated waveguide.

We demonstrate a proof of concept of a novel and compact integrated mechano-optical sensor for H(2) detection based on a microcantilever suspended above a Si(3)N(4) grated waveguide. The fabricated devices are mechanically and optically modeled and characterized. Sensing operation of the sensor is demonstrated with 1% H(2) in N(2).

Nanometer arrays of functional light harvesting antenna complexes by nanoimprint lithography and host-guest interactions.

We show an approach based on a combination of site-directed mutagenesis, NIL and multivalent host-guest interactions for the realization of engineered ordered functional arrays of purified components of the photosynthetic system, the membrane-bound LH2 complex. In addition to micrometer-scale patterned structures, we demonstrated the use of nanometer-scale hard NIL stamps to generate functional protein arrays approaching molecular dimensions.

Fluorescence of dyes adsorbed on highly organized, nanostructured gold surfaces.

It is shown that fluorescent dyes can be adsorbed selectively on gold nanoparticles which are immobilized on a glass substrate and that the fluorescence originating from the adsorbed dyes exhibits significantly less quenching when compared to dyes adsorbed on bulk gold. Self-assembled monolayers of lissamine sulfide molecules have been studied both on bulk gold and on glass surfaces bearing gold nanoparticles. Gold nanoparticles have been arranged in ordered, two-dimensional patterns, with periodicity in the microm range and used as substrate for the fluorescent dyes.

Guest encapsulation and self-assembly of molecular capsules in polar solvents via multiple ionic interactions.

Herein we report the formation and characterization of a novel type of capsules resulting from the self-association between oppositely charged complementary building blocks in MeOH/H2O. The assembly is based on the interaction between tetraamidinium calix[4]arenes 1a-d and tetrasulfonato calix[4]arene 2. Evidence for the formation of the expected 1:1 assemblies is provided by proton NMR, ESI-MS, and ITC.

Noncovalent Synthesis Using Hydrogen Bonding.

Hydrogen bonds are like human beings in the sense that they exhibit typical grouplike behavior. As an individual they are feeble, easy to break, and sometimes hard to detect. However, when acting together they become much stronger and lean on each other.