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Current bioinks for 3D bioprinting, such as gelatin-methacryloyl, are generally low viscosity fluids at room temperature, requiring specialized systems to create complex geometries.Adding decellularized extracellular matrix microparticles derived from porcine tracheal cartilage to gelatin-methacryloyl creates a yield stress fluid capable of forming self-supporting structures. This bioink blend performs similarly at 25°C to gelatin-methacryloyl alone at 15°C in linear resolution, print fidelity, and tensile mechanics.This method lowers barriers to manufacturing complex tissue geometries and removes the need for cooling systems.

Hydrophobic alkyl side chains steer water toward the charge-ion pair, giving rise to large interconnected water clusters that promote ion conduction.

The application of 3D printing of thermoplastics by Material Extrusion (MatEx) has commonly been limited by their poor mechanical strength that results from voids and weak interfaces between printed layers. Here, we demonstrate that core–shell structured filaments made of polycarbonate-based thermoplastics can achieve synergistic improvement in their interfacial bonding from the combination of high-glass transition temperature (T g)/high-viscosity core and low-T g/low-viscosity shell. Tensile strength along the printing direction was enhanced with the core–shell filaments. Layer-interfacial bonding strength as determined by Izod impact tests of the 3D printed parts is significantly improved by using filaments either with only a core–shell T g mismatch or both T g/viscosity core–shell mismatch. The mechanical behavior can be rationalized in terms of improved inter-layer molecule diffusion by a low T g/viscosity shell, better printability at higher temperature due to the core with higher melt strength, and better bulk mechanical strength of high-viscosity/T g core.

The local environment within a hydrogel influences the properties of water, including the propensity for ice crystallization. Water-swollen amphiphilic copolymers produce tunable nanoscale environments, which are defined by hydrophobic associations, for the water molecules. Here, the antifreeze properties for equilibrium-swollen amphiphilic copolymers with a common hydrophilic component, hydroxyethyl acrylate (HEA), but associated through crystalline (octadecyl acrylate, ODA) or rubbery (ethylhexyl acrylate, EHA) hydrophobic segments, are examined. Differences in the efficacy of the associations can be clearly enunciated from compositional solubility limits for the copolymers in water (2.6 mol % ODA vs ≤14 mol % EHA), and these differences can be attributed to the strength of the association. The equilibrium-swollen HEA-ODA copolymers are viscoelastic solids, while the swollen HEA-EHA copolymers are viscoelastic liquids. Cooling these swollen copolymers to nearly 200 K induces some crystallization of the water, where the fraction of water frozen depends on the details of the nanostructure. Decreasing the mean free path of water by increasing the ODA composition from 10 to 25 mol % leads to fractionally more unfrozen water (66-87%). The swollen HEA-EHA copolymers only marginally inhibit ice (13%) except with 45 mol % EHA, where nearly 60% of the water remains amorphous on cooling to 200 K. In general, the addition of the EHA leads to less effective ice inhibition than analogous covalently crosslinked HEA hydrogels (19.9 ± 1.8%). These results illustrate that fluidity of confining surfaces can provide pathways for critical nuclei to form and crystal growth to proceed.

Micelles formed within coacervate phases can impart functional properties, but it is unclear if this micellization provides mechanical reinforcement of the coacervate whereby the micelles act as high functionality crosslinkers. Here, we examine how sodium dodecyl sulfate (SDS) influences the structure and properties of Pluronic F108-polyacrylic acid (PAA) coacervates as SDS is known to decrease the aggregation number of Pluronic micelles. Increasing the SDS concentration leads to larger water content in the coacervate and an increase in the relative concentration of PAA to the other solids. Rheological characterization with small angle oscillatory shear (SAOS) demonstrates that these coacervates are viscoelastic liquids with the moduli decreasing with the addition of the SDS. The loss factor (tan

Additive Manufacturing (AM) enables the direct production of complex geometries from computer-aided designs (CAD). The AM fabrication process is often executed in a layer-by-layer manner, whereby minute printing errors in one layer can manifest significant defects in the final part. In-situ quality monitoring and control are currently limited for AM processes and cause low repeatability. Recently. advanced imaging is increasingly invested in AM and leads to the proliferation of layerwise imaging data, which provides an opportunity to transform quality control of AM from post-build inspection to in-situ quality monitoring. However, existing methodologies for in-situ inspection primarily focus on key characteristics of image profiles that tend to be limited in the ability to analyze the variance components, as well as root causes and failure patterns that are critical to process improvement. This letter presents an Additive Gaussian Process with dependent layerwise correlation (AGP-D) to model the spatio-temporal correlation of layerwise imaging data for AM quality monitoring. The AGP-D consists of three independent GP modules. The first GP approximates the base profile, whereas the second and third GP capture the correlation within the same layer and among layers, respectively. Based on posterior predictions of new layers, Hotelling ${{\boldsymbol{T}}^2}$ and generalized likelihood ratio (GLR) control tests are formulated to detect process shifts in the newly fabricated layer and analyze root causes. The proposed methodology is evaluated and validated using both simulation data and real-world case study of a cylinder build fabricated by a laser powder bed fusion (LPBF) machine. Experimental results show the proposed AGP-D is effective for real-time modeling and monitoring of layerwise-correlated imaging data.

This study assesses the occurrence of trace elements (TEs) in sediments of the southern Caspian Sea. A total of 16 shoreline sediment samples and 15 seabed sediment samples along five coastal transects were studied. The mean concentration of TEs follows the order of Zn > V > Cr > Ni > Cu > Pb > Co > As > Sb > Mo > Cd. The TEs had an uneven, heterogeneous distribution within the shoreline and seabed sampling sites. This is due to that the study area comprises a large number of different pollution sources, also different sediment physicochemical characteristics. Levels of individual TEs within the seabed sediment transects were higher where their shoreline sites had higher concentrations, reflecting that the coastal sites play an important role in diffusing the contaminants towards the sea. The main anthropogenic source of TEs in this highly populated region, especially in the western part, is likely a large number of discharge points of greywater entering the sea. In addition, dominant fishing industry, tourism, intense agriculture, and textile and paper industry, as well as several other commercial activities, contribute significantly to the overall loading of TEs. Based on the statistical analyses, the organic matter and mud fraction had a strong explanatory value for the spatial variation of Cu, while oxyhydroxides of Fe and Mn had good explanatory factors to govern the spatial variation of other TEs. Pb and Zn had a relatively high partition coefficient (Kd), reflecting the affinity of these elements to be sorbed to the sediment phase. Cd and Sb had lower Kd, tending to remain in the aqueous phase. Geochemical indices indicated high enrichment of Cd, Sb, Zn, and Pb at a number of sampling sites, reflecting potential local sources of contamination. The Sisangan recreational area was identified as the most contaminated site. From a public health perspective, the non-carcinogenic risk of TEs was significant only at this site. The carcinogenic risks of Pb(II) and As(III) in adults, and Pb(II), Cd(II), and As(III) in children, were tolerable.

Most cells can sense and change their shape to carry out fundamental cell processes. In many eukaryotes, the septin cytoskeleton is an integral component in coordinating shape changes like cytokinesis, polarized growth, and migration. Septins are filament-forming proteins that assemble to form diverse higher-order structures and, in many cases, are found in different areas of the plasma membrane, most notably in regions of micron-scale positive curvature. Monitoring the process of septin assembly in vivo is hindered by the limitations of light microscopy in cells, as well as the complexity of interactions with both membranes and cytoskeletal elements, making it difficult to quantify septin dynamics in living systems. Fortunately, there has been substantial progress in the past decade in reconstituting the septin cytoskeleton in a cell-free system to dissect the mechanisms controlling septin assembly at high spatial and temporal resolutions. The core steps of septin assembly include septin heterooligomer association and dissociation with the membrane, polymerization into filaments, and the formation of higher-order structures through interactions between filaments. Here, we present three methods to observe septin assembly in different contexts: planar bilayers, spherical supports, and rod supports. These methods can be used to determine the biophysical parameters of septins at different stages of assembly: as single octamers binding the membrane, as filaments, and as assemblies of filaments. We use these parameters paired with measurements of curvature sampling and preferential adsorption to understand how curvature sensing operates at a variety of length and time scales.

Optimization of three-dimensional (3D) print conditions for material extrusion of plastics by fused filament fabrication typically involves trade-offs between mechanical properties and dimensional ...

Layer-by-layer (LbL) assembly facilitates controlled coatings on a variety of surfaces with the ability to manipulate the composition through the thickness by selection of the complementary pairs. However, the characterization of these composition profiles tends to be destructive and requires significant compositional differences that can limit their utility. Here, we demonstrate the ability to non-destructively quantify the depth dependence of the allyl content associated with the selective incorporation of poly(sodium acrylate-co-allylacrylamide) (84 : 16 mol : mol) (allyl-PAA) in LbL films based on the assembly of poly(diallyldimethylammonium chloride) (PDAC)/poly(acrylic acid) (PAA) and PDAC/allyl-PAA. Although the atomic composition of the film is not dramatically influenced by the change between PAA and allyl-PAA, the absorption in the IR near 1645 cm−1 by the allyl group provides sufficient optical contrast to distinguish the LbL components with spectroscopic ellipsometry. The use of IR spectroscopic ellipsometry can determine the thickness of layers that contain allyl-PAA and also gradients that develop due to re-arrangements during the LbL process. With multiple films fabricated simultaneously, the location of the gradient between the 1st and 2nd series of multilayers (e.g., first PDAC/PAA bilayers and then PDAC/allyl-PAA bilayers) can be readily assessed. The results from a variety of different multilayer architectures indicate that the gradient is located within the thickness expected for the 1st deposited bilayer stack (PDAC/PAA or PDAC/allyl-PAA). These results are indicative of a dynamic dissolution–deposition process (in- and out- diffusion) during the fabrication of these LbL films. These results provide additional evidence into the mechanisms for exponential growth in LbL assemblies. The ability to quantify a gradient with the low contrast system examined indicates that spectroscopic IR ellipsometry should be able to non-destructively determine compositional gradients for most polymer films where such gradients exist.

Acoustic/elastic metamaterials that rely on engineered microstructures instead of chemical composition enable a rich variety of extraordinary effective properties that are suited for various applications including vibration/noise isolation, high-resolution medical imaging, and energy harvesting and mitigation. However, the static nature of these elastic wave guides limits their potential for active elastic-wave guiding, as microstructure transformation remains a challenge to effectively apply in traditional elastic metamaterials due to the interplay of polarization and structural sensitivity. Here, a tunable, locally resonant structural waveguide is proposed and demonstrated for active vibration bandgap switching and elastic-wave manipulation between 1000–4000 Hz based on 3D printed building blocks of zinc-neutralized poly(ethylene-co-methacrylic acid) ionomer (Surlyn 9910). The ionomer exhibits shape memory behavior to enable rearrangement into new shape patterns through application of thermal stimuli that tunes mechanical performance in both space and time dimensions (4D metamaterial). The thermally induced shape-reorganization is programed to flip a series of frequency bands from passbands to bandgaps and vice versa. The continuously switched bandwidth can exceed 500 Hz. Consequently, altering the bandgap from “on” to “off” produces programmable elastic-wave propagation paths to achieve active wave guiding phenomena. An anisotropic cantilever-in-mass model is demonstrated to predict the self-adaptive dynamic responses of the printed structures with good agreement between the analytical work and experimental results. The tunable metamaterial-based waveguides illustrate the potential of 4D printed shape memory polymers in the designing and manufacturing of intelligent devices for elastic-wave control and vibration isolation.

Thermoplastic elastomers based on ABA triblock copolymers are typically limited in modulus and strength due to crack propagation within the brittle regions when the hard end-block composition favors morphologies that exhibit connected domains. Increasing the threshold end-block composition to achieve enhanced mechanical performance is possible by increasing the number of junctions or bridging points per chain, but these copolymer characteristics also tend to increase the complexity of the synthesis. Here, we report an in situ polymerization method to successfully increase the number of effective junctions per chain through grafting of poly(styrene) (PS) to a commercial thermoplastic elastomer, poly(styrene)–poly(butadiene)–poly(styrene) (SBS). The strategy described here transforms a linear SBS triblock copolymer–styrene mixture into a linear-comb-linear architecture in which poly(styrene) (PS) grafts from the mid-poly(butadiene) (PBD) block during the polymerization of styrene. Through systematic variation in the initial SBS/styrene content, nanostructural transitions from disordered spheres to lamellar through reaction-induced phase transitions (RIPT) were identified as the styrene content increased. Surprisingly, maximum mechanical performance (Young's modulus, tensile strength, and elongation at break) was obtained with samples exhibiting lamellar nanostructures, corresponding to overall PS contents of 61–77 wt% PS (including the original PS in SBS). The PS grafting from the PBD block increases the modulus and the strength of the thermoplastic elastomer while preventing brittle fracture due to the greater number of junctions afforded by the PS grafts. The work presented here demonstrates the use of RIPT to transform standard SBS materials into polymer systems with enhanced mechanical properties.

Seeded growth rates of ritonavir in copovidone at 75% relative humidity (RH) and 50 °C were evaluated by single-particle tracking second harmonic generation (SHG) microscopy and found to be ∼3-fold slower for crystallites at the surface compared to the bulk. The shelf lives of final dosage forms containing amorphous solid dispersions (ASDs) are often dictated by the rates of active pharmaceutical ingredient crystallization. Upon exposure to elevated RH, the higher anticipated water content near the surfaces of ASDs has the potential to substantially impact nucleation and growth kinetics relative to the bulk. However, quantitative assessment of these differences in growth rates is complicated by challenges associated with discrimination of the two contributions (supersaturation and molecular mobility) in ensemble-averaged measurements. In the present study, "sandwich" materials were prepared, in which sparse populations of ritonavir single-crystalline seeds were pressed between two similar ASD films to assess bulk crystallization rates. These sandwich materials were compared and contrasted with analogously prepared "open-faced" samples, without the capping film, to assess the surface crystallization rates. Single-particle analysis by SHG microscopy time-series during in situ crystallization produced average growth rates of 3.8 μm/h for bulk columnar crystals with a particle-to-particle standard deviation of 0.9 μm/h. In addition, columnar crystal growth rates for surface particles were measured to be 1.3 μm/h and radiating crystal growth rates for surface particles were measured to be 1.0 μm/h, both with a particle-to-particle deviation of 0.4 μm/h. The observed appearance of radiating crystals upon surface seeding is attributed to reduced ritonavir solubility upon water adsorption at the interface, leading to higher defect densities in crystal growth. Despite substantial differences in crystal habit, correction of the surface growth rates by a factor of 4 from geometric effects resulted in relatively minor but statistically significant differences in the growth kinetics for the two local environments. These results are consistent, with viscosity being a relatively weak function of water absorption coupled with primarily diffusion-limited growth kinetics.

This paper presents a novel technique to improve geological understanding in regions of historic mining activity. This is achieved through inferring the orientations of geological structures from the imprints left on the landscape by past mining activities. Open source high resolution LiDAR datasets are used to fine-tune a deep convolutional neural network designed initially for Lunar LiDAR crater identification. By using a transfer learning approach between these two very similar domains, high accuracy predictions of pit locations can be generated in the form of a raster mask of pit location probabilities. Taking the raster of the predicted pit location centres as an input, a Hough transformation is used to fit lines through the centres of the detected pits. The results demonstrate that these lines follow the patterns of known mineralised veins in the area, alongside highlighting veins which are below the scale of the published geological maps.

Microwave heating provides an efficient method to rapidly heat materials through interaction of microwaves with the media. Here, we demonstrate the rapid synthesis of mesoporous cobalt oxide films through the heating of the silicon substrate by microwaves. A non-sol-gel approach based on cobalt nitrate-citric acid complex cooperative assembly with a poly[methoxy poly(ethylene glycol)methacrylate]-block-poly(butyl acrylate) (PMPEGMA-b-PBA) block copolymer was used to fabricate the cobalt oxide through a cobalt carbonate intermediate. The time required to convert cobalt carbonate to cobalt oxide with the full removal of the PMPEGMA-b-PBA template can be decreased by two orders of magnitude with microwaves in comparison to standard heating in a furnace at 350 °C. At the highest microwave power examined (1500 W), this can be accomplished within 2 s, while >5 min is required at 350 °C in a furnace. At a microwave power of

Poly(ethylene glycol) (PEG) tends to be considered low fouling, which has led to its use in a wide variety of applications. Amphiphilic polyols, such as Antifoam 204, are commonly used as surfactants in fermentation processes due to their limited toxicity and low cost, but these polyols in aqueous solutions can unexpectedly swell membranes. Here we examine the interactions of PEG or poly(propylene glycol) (PPG) with amphiphilic substituted norbornene copolymers through swelling in dilute aqueous solution. The effect of molecular mass (Mn) of the polyol (PEG and PPG) in aqueous (1 wt% butanol) solution on the swelling and mechanical properties of a series of poly(alkyl norbornene-co-hexafluoroisopropanol norbornene) is systematically investigated using a quartz crystal microbalance with dissipation. At 10 ppm of PEG, the swelling is less than 20% for all of the copolymers examined and the swelling is independent of PEG Mn. Although PPG at the lowest Mn examined leads to similar swelling to PEG, the swelling induced by PPG increases with Mn to reach a maximum at Mn = 3.1 kg mol-1. Pluronic L121 is similar compositionally to Antifoam 204, but the equilibrium swelling is decreased by nearly a factor of 2, which is attributed to the higher Mn of Pluronic L121. The limited dependence on the alkyl chain in the copolymer suggest that the interactions between the polyol and hexafluoroisopropanol moiety in the copolymer drive the uptake by the membrane through bound water with the unassociated ether in the PPG that increases swelling with increasing Mn, but a finite size effect limits the swelling for sufficiently large polymer additives.

The flux of terrestrial dissolved inorganic phosphorous (DIP, i.e. PO43−) via rivers into coastal seas is usually calculated by simply multiplying its concentration with the corresponding water flow at the river mouth. Subsequent adsorption/desorption of DIP onto suspended sediment and the influence of salinity in the estuary are often overlooked. A series of DIP adsorption/desorption experiments under different salinities (0, 5, 15, 30) and suspended sediment concentrations (1–40 g L−1) were conducted in order to assess the potential influence of these factors on the overall DIP loading to the coastal zone. The effect of different sea-salt ions on DIP adsorption/desorption was also assessed by comparing different experimental solutions (NaCl solution, artificial seawater and real seawater). In estuaries, the adsorption of DIP to suspended sediments was greater than desorption, and the net adsorption increased with increasing concentration of suspended sediments and salinity. This enhanced DIP adsorption onto suspended sediment reduces the riverine discharge of DIP to coastal ecosystems. Disregarding this process, especially for the gated estuaries with high sediment resuspension, potentially leads to an overestimation of the terrestrial DIP input to the coastal region.

There are large knowledge gaps concerning environmental levels and fate of many organic pollutants, particularly for chemicals of emerging concern in tropical regions of the Global South. In this study, we investigated the levels of chlorinated paraffins (CPs) and dechloranes in air and soil in rural, suburban, and urban regions in and around Dar es Salaam, Tanzania. Samples were also collected near the city's main municipal waste dumpsite and an electronic waste (e-waste) handling facility. In passive air samples, short chain CPs (SCCPs) dominated, with an average estimated concentration of 22 ng/m3, while medium chain CPs (MCCPs) had an average estimated concentration of 9 ng/m3. The average estimated air concentration of ∑dechloranes (Dechlorane Plus (DP) + Dechlorane 602 + Dechlorane 603) was three to four orders of magnitudes lower, 2 pg/m3. In soil samples, MCCPs dominated with an average concentration of 640 ng/g dw, followed by SCCPs with an average concentration of 330 ng/g dw, and ∑dechloranes with an average concentration of 0.9 ng/g dw. In both air and soil, DP was the dominating dechlorane compound. Urban pulses were observed for CPs and dechloranes in air and soil. CPs were in addition found in elevated levels at the municipal waste dumpsite and the e-waste handling facility, while DPs were found in elevated levels at the e-waste handling facility. This suggests that waste handling sites represent important emission sources for these pollutants. Investigations into seasonal trends and environmental fate of CPs and dechloranes showed that monsoonal rain patterns play a major role in governing air concentrations and mobility, particularly for the less volatile MCCPs and dechloranes. This study is the first to report levels of CPs in air from sub-Saharan Africa, and DP, Dechlorane 602, and Dechlorane 603 in soil from sub-Saharan Africa.

Beidagang Wetland (BW) Nature Reserve is centrally situated in Tianjin City, experiencing an extreme industrial development. This study uses index characteristic analysis systems for assessing the individual and combined heavy metal pollution loading in the water during the spring and autumn seasons. By combining the pollution level of single pollutant, a more comprehensive evaluation of water quality in BW was achieved. Water quality was worst during autumn due to high level of Cd and Pb, which indicate the type of anthropogenic activities have a serious effect on heavy metal pollution in BW. In addition, high exchangeable amounts of Cd ( 40%) were found in the sediments of BW, indicating Cd pollution has emerged. There is a need for appropriate abatement actions curbing heavy metal loading and improving water quality of the BW Nature Reserve, thereby ensuring a sustainable management of its ecosystem services.

Cytochromes P450 17A1 (CYP7A1) and 21A2 (CYP21A2) catalyze key reactions in the production of steroid hormones, including mineralocorticoids, glucocorticoids, and androgens. With the ultimate goal of designing probes that are selectively metabolized to each of these steroid types, fluorinated derivatives of the endogenous substrates, pregnenolone and progesterone, were prepared to study the effects on CYP17A1 and CYP21A2 activity. In the functional assays, the hydroxylase reactions catalyzed by each of these enzymes were blocked when fluorine was introduced at the site of metabolism ( positions 17 and 21 of the steroid core, respectively). CYP17A1, furthermore, performed the 17,20-lyase reaction on substrates with a fluorine installed at the 21-position. Importantly, none of the substitutions examined herein prevented compound entry into the active sites of either CYP17A1 or CYP21A2 as demonstrated by spectral binding assays. Taken together, the results suggest that fluorine might be used to redirect the metabolic pathways of pregnenolone and progesterone to specific types of steroids.

Nanoparticle-functionalized 2D material networks are promising for a wide range of applications, but in situ formation of nanoparticles is commonly challenged by rapid growth. Here, we demonstrate controlled synthesis of small and dispersed iron oxide nanoparticles on reduced graphene oxide (rGO) networks through rapid localized heating with microwaves with low-cost iron nitrate as the precursor. The strong coupling of the microwave radiation with the rGO network rapidly heats the network locally to decompose the iron nitrate and generate iron oxide nanoparticles, while cessation of microwaves leads to rapid cooling to minimize crystal growth. Small changes in the microwave reaction time (

High porosity and surface areas of ordered mesoporous materials provide substantial capacity for loading of guest molecules and the well-defined morphology of such materials can control their transport for controlled release. Here, the loading and release of mitoxantrone from unmodified ordered mesoporous carbon films is monitored using UV/Vis spectroscopy. Organic-organic self-assembly of Pluronic F127 with phenolic resin leads to interconnected elliptical pores (≈2 nm) in the film after carbonization. Interestingly, the total loading (2.6 ± 0.4 μg/cm(2)) and release of mitoxantrone is independent of film thickness (50–400 nm), suggesting diffusion limitations in pore filling. With alternative template, the pore size increases to ≈5 nm and the mitoxantrone loading increases to 3.5 ± 0.9 μg/cm(2), but the loading still remains thickness independent. Using phosphate buffered saline at 37 °C, less than 60 % of the loaded mitoxantrone is readily released from the mesoporous carbon films over a two-week period. The release profile includes an initial burst with a modest fraction (< 20 %) of the loaded drug released within the first day, followed by a near linear release over the subsequent 5–9 days. Interestingly, the smaller pores (ca. 2 nm) release nearly 50 % more mitoxantrone over 2 weeks than the larger pores (ca. 5 nm), despite the lower initial loading. These results illustrate potential limitations as well as opportunities for the use of highly hydrophobic porous materials for the controlled release of hydrophobic biologically active compounds as drug delivery systems.

Lithium ion capacitors (LICs) are energy storage devices integrating the complementary features of both supercapacitors and lithium ion batteries to simultaneously reach high energy and power densities. One of the major challenges in LIC technology is the kinetic imbalance between the faradaic insertion anode and capacitive cathode. Therefore, the design of electrode materials is crucial to enhance the rate performance of anode and the capacitance of the cathode in LIC devices. In this work, novel LICs were demonstrated with nanostructured cathode and anode. A vertically-aligned carbon nanoflakes (VACNFs) cathode provided high electrochemically active surface area and excellent conductivity, while a metal organic framework (MOF) derived carbonized nickel cobalt oxide (cNiCo2O4) anode ensured fast conversion reactions and remarkable cyclability. Electrochemical characterization of individual electrode confirmed that both electrodes exhibited good electron and ion transport capability. The LICs were fabricated with optimized electrode active materials loading to deliver high energy densities at desired charge/discharge rates. The devices exhibited energy density up to 136.9 W h/kg (at 200 W/kg). At higher power density of 40 kW/kg, under which a full charge-discharge can be finished within 4 s, the LICs could still deliver an energy density of 26.44 W h/kg. The devices also showed a good cycle stability (≈90% capacitance retention after 9000 cycles, under current density of 4 A/g) within the voltage range of 1–4.2 V.

One key limitation of lithium metal electrodes is their propensity for dendrite formation that limits their use in commercial batteries. Here, a simple surface modification method was demonstrated ...

The cooperative assembly of functional precursors with block copolymers (BCPs) is a powerful, general route to fabricate ordered mesoporous materials, but the precise tuning of the mesopore size generally requires trial and error to obtain the correct BCP template or appropriate swelling agent. Here, we demonstrate the ability to effectively modulate both expansion and contraction of the ordered cylindrical mesopores relative to those obtained from cooperatively assembled Pluronic F127, resol, and tetraethylorthosilicate. The two key physical parameters for the swelling agents are their hydrophobicity, as quantified by the octanol-water partition coefficient (Kow), and Hansen solubility parameters that describe the interactions of the solvent with the different components of the BCP template. Four low volatility solvents are examined that span a wide Kow with up to 90 wt % solvent relative to the Pluronic F127. Glycerol triacetate (Kow < 1) can decrease the average mesopore size from 5.9 to 4.8 nm due to segmental screening of the interactions in the Pluronic F127 to decrease chain stretching at intermediate loadings. A modest increase in mesopore size to 8.1 nm can be achieved with trimethylbenzene (TMB, Kow = 3.42). Dioctyl phthalate (DOP), which is slightly more hydrophobic (Kow = 8.1), is more effective than TMB at expanding the pore size (maximum: 13.5 nm) without loss of ordered structure. A more hydrophobic solvent, tris (2-ethylhexyl) trimellitate (Kow = 12.5), is less effective at increasing the pore size (maximum: 8.2 nm). The Hansen solubility parameters for DOP most closely match those of the hydrophobic segment in the Pluronic F217 template. We attribute this similarity, which is related to the solvent quality, to the improved efficacy of DOP in increasing the pore size. These results illustrate that both the Hansen solubility parameters (relative to the hydrophobic segment of the template) and relative hydrophobicity of the swelling agent determine the obtainable pore sizes in cooperatively assembled ordered mesoporous materials.

Polymer membranes represent a low cost, low energy solution to separating biologically derived chemicals from fermentation. However, the performance of these membranes is commonly limited by fouling caused by biological components, but additives are also included in typical fermentation broths that can interact with the polymer membrane. Here, we examine how a common polyol antifoam agent (Antifoam 204) dramatically swells and plasticizes a high performing biobutanol membrane copolymer of hydroxyhexafluoroisopropyl and n-butyl substituted norbornene. When equilibrated against 1 wt % (aq) butanol, the solvent in the copolymer increases from 40 vol % at 1 ppm of antifoam and >80 vol % at 100 ppm of antifoam. The effect of the antifoam on the properties of the copolymer as determined by QCM-D is much more significant than that of the butanol concentration. Even with 4 wt % butanol (greater than typically viable for biobutanol), the copolymer swells