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While metal oxides and metal sulfides have been extensively studied for gas sensing applications, there are no extensive reports on gas sensing properties of metal diborides. Here, for the first time, we have investigated the conductometric gas sensing behavior of HfB2 nanoparticles. The HfB2 nanoparticles is synthesized via a sol-gel method and characterized using X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The gas sensor is fabricated by drop casting the HfB2 nanoparticles on interdigitated Ag/Pd electrodes. The sensor exhibited a promising NO2 sensing performance at the operating temperature of 200 °C. Interestingly, it is found that resistance of the sensor decreases upon exposure to both oxidizing and reducing gases, which does not follow the gas sensing behaviors of the widely investigated metal oxides. In addition, the sensor response is minimally influenced by oxygen background concentration. These results highlight that HfB2 nanoparticles exhibit very unique sensing characteristics.

Green solvent mixes are applied in printed mesoscopic perovskite solar cells and modules, achieving 13.8% PCE at 1 cm2 and >9% PCE in a 220 cm2 module. This shows how green solvent engineering can aid improvement and scale-up in emerging technologies.

Carbon based Perovskite Solar cells (C–PSCs) have emerged as the most promising candidates for commercialisation in the field of perovskite photovoltaics, as they are highly stable, low cost and make use of easily scaled manufacturing techniques. However, the limited conductivity of the carbon electrode inhibits performance and represents a significant barrier to commercial application. Τhis work presents a scalable method for enhancing the carbon electrode conductivity through the integration of aluminium and copper grids into prefabricated C–PSCs. Adhered to the cells using an additional low temperature carbon ink, the metallic grids were found to dramatically reduce top electrode series resistance, leading to a large improvement in fill factor and efficiency. After grid integration, the 1 cm2 C–PSCs yielded power conversion efficiency (PCE) of 13.4% and 13% for copper and aluminium respectively, while standard C–PSCs obtained PCE of 11.3%. Performance is also significantly augmented in the case of larger-scale 11.7 cm2 modules, where PCEs went from 7.7% to 10% and 11% for aluminium and copper grids respectively. This technique offers a fast and low temperature route to high-performance, large-area C–PSCs and could therefore have serious potential for application to the high-volume manufacture of perovskite cells and modules.

Carbon aerogels (CAs) combine unique properties including ultra-high surface area, high electrical conductivity, corrosion resistance, and robust mechanical properties making them ideal materials for electrochemical applications. Traditional CA synthesis results in isotropic, random nanoporous networks that work well for applications relying on diffusional mass transport. However, many applications would benefit from integration of engineered macroporous network structures that enable directed pressure-gradient-driven mass transport. Here, we report on using 3D-printed sacrificial polymeric templates to generate templated CAs (t-CAs) with integrated engineered nonrandom macroporous network structures. Specifically, we used projection micro-stereo-lithography (PμSL) and two-photon polymerization direct laser writing (2PP-DLW) to fabricate millimeter-to-centimeter-sized 3D sacrificial polymeric templates with features ranging from tens of microns (PμSL) to 100s of nanometers (2PP-DLW). T-CAs were fabricated by infiltrating the templates with resorcinol-formaldehyde (RF) precursor solution, followed by carbonization at 1050 °C to simultaneously convert the RF gel to a CA and decompose the 3D-printed template, leaving an embedded templated macroporous network structure behind. X-ray computer tomography confirms integration of the macroporous architecture defined by the template. The templated macroporous architecture improves mass transport in t-CAs compared to traditional bulk CA as demonstrated by more uniform activation and their response in electrochemical cyclic voltammetry and galvanostatic charge-discharge tests.

Purpose A novel modelling approach is proposed to study ozone distribution and destruction in indoor spaces. The level of ozone gas concentration in the air, confined within an indoor space during an ozone-based disinfection process, is analysed. The purpose of this work is to investigate how ozone is distributed in time within an enclosed space. Design/methodology/approach A computational methodology for predicting the space- and time-dependent ozone concentration within the room across the consecutive steps of the disinfection process (generation, dwelling and destruction modes) is proposed. The emission and removal of ozone from the air volume are possible by means of a generator located in the middle of the room. This model also accounts for ozone reactions and decay kinetics, and gravity effect on the air. Finding This work is validated against experimental measurements at different locations in the room during the disinfection cycle. The numerical results are in good agreement with the experimental data. This comparison proves that the presented methodology is able to provide accurate predictions of the time evolution of ozone concentration at different locations of the enclosed space. Originality/value This study introduces a novel computational methodology describing solute transport by turbulent flow for predicting the level of ozone concentration within a closed room during a COVID-19 disinfection process. A parametric study is carried out to evaluate the impact of system settings on the time variation of ozone concentration within the space considered.

We describe a robust and scalable method to produce crinkled hexagonal boron nitride (h-BN) nanofoam from graphite in a single-step, leapfrog-like process. The conversion is based on carbothermic r...

Previous works from our laboratory have firmly established that aerogels are a suitable substrate to elicit accelerated neurite extension. On non-conducting aerogels, in the presence of an externally-applied DC bias, neurons extended neurites which were preferentially aligned towards the anode. In this investigation, we sought to determine whether electrically-conductive carbon aerogels elicited a more robust alignment of neurites toward the anode than non-conductive aerogels due to the capacity of conductive aerogels to sustain a current, thereby providing a direct interface between neurons and the external electrical stimulus. To determine if this was the case, we plated PC12 neuronal cells on electrically conductive carbon aerolges derived from acetic acid-catalized resorcinol formaldehyde aerogels (ARF-CA) and subjected them to an external electric field. The voltages applied at the electrodes of the custom-built electro-stimulation chamber were 0 V, 15 V, and 30 V. For each voltage, the directionality and length of the neurites extended by PC12 cells were determined and compared to those observed when PC12 cells were plated on non-conductive aerogels subjected to the same voltage. The results show that the directionality of neurite extension was similar between conductive and non-conductive aerogels. A higher neurite length difference was observed on conductive aerogels with increasing voltage, 43% and 106% for 0-15 V and 0-30 V respectively, compared to non-conductive aerogels, 12% and 20%. These findings indicate that conductive carbon aerogels have a greater potential as scaffolds for nerve regeneration than non-conductive ones.

Multi-functional membranes with high permeance and selectivity that can mimic nature's designs have tremendous industrial and bio-medical applications. Here, we report a novel concept of a 3D nanometer (nm)-thin membrane that can overcome the shortcomings of conventional membrane structures. Our 3D membrane is composed of two three-dimensionally interwoven channels that are separated by a continuous nm-thin amorphous TiO2 layer. This 3D architecture dramatically increases the surface area by 6000 times, coupled with an ultra-short diffusion distance through the 2–4 nm-thin selective layer that allows for ultrafast gas and water transport, ∼900 l m−2 h−1 bar−1. The 3D membrane also exhibits a very high ion rejection (R ∼ 100% for potassium ferricyanide) due to the combined size- and charge-based exclusion mechanisms. The combination of high ion rejection and ultrafast permeation makes our 3DM superior to the state-of-the-art high-flux membranes whose performances are limited by the flux-rejection tradeoff. Furthermore, its ultimate Li+ selectivity over polysulfide or gas can potentially solve major technical challenges in energy storage applications, such as lithium–sulfur or lithium–O2 batteries.

Liquid chromatography-mass spectrometry methods were required to afford the rapid separation and detection of purines and small organic acids. These compounds are found in sweat and sebum and are potential biomarkers for the early detection of pressures sores. Two ultrahigh-performance supercritical fluid chromatography-mass spectrometry assays have been successfully developed for both classes of compounds. Separation for purines was achieved using a gradient of supercritical carbon dioxide and methanol with a 1-aminoanthracene sub 2 µm particle size column followed by positive ion electrospray ionization. Separation for organic acids was achieved using a gradient of supercritical carbon dioxide and methanol (50 mM ammonium acetate 2% water) with a Diol sub 2 µm particle size column followed by negative ion electrospray ionization. Calibration curves were created in the absence of internal standards and R2 values > 0.96 were achieved using single ion monitoring methods for the protonated purines and the deprotonated acids. The two new assays afford rapid analytical methods for the separation and detection of potential biomarkers in human sweat leading to the early detection and prevention of pressure sores.

IntroductionReal-world trial data comparing single- with multiple-inhaler triple therapy (MITT) in COPD patients are currently lacking. The effectiveness of once-daily single-inhaler fluticasone furoate (FF)/umeclidinium (UMEC)/vilanterol (VI) and MITT were compared in usual clinical care.MethodsINTREPID was a multicentre, randomised, open-label, phase IV effectiveness study comparing FF/UMEC/VI 100/62.5/25 µg via the ELLIPTA inhaler with a clinician's choice of any approved non-ELLIPTA MITT in usual COPD clinical practice in five European countries. Primary end-point was proportion of COPD Assessment Test (CAT) responders (≥2-unit decrease in CAT score from baseline) at week 24. Secondary end-points in a subpopulation included change from baseline in forced expiratory volume in 1 s (FEV1) and percentage of patients making at least one critical error in inhalation technique at week 24. Safety was also assessed.Results3092 patients were included (FF/UMEC/VI n=1545; MITT n=1547). The proportion of CAT responders at week 24 was significantly greater with FF/UMEC/VI versus non-ELLIPTA MITT (OR 1.31, 95% CI 1.13–1.51; p1 was significantly greater with FF/UMEC/VI (77 mL versus 28 mL; treatment difference 50 mL, 95% CI 26–73 mL; pConclusionsIn a usual clinical care setting, treatment with once-daily single-inhaler FF/UMEC/VI resulted in significantly more patients gaining health status improvement and greater lung function improvement versus non-ELLIPTA MITT.

We demonstrate the synthesis of high-surface-area, low-density refractory aerogels. The monolithic hafnium boride (HfB2) and zirconium boride (ZrB2) aerogels are prepared via borothermal reduction ...

In order to achieve semi-transparency in perovskite solar cells, the electrode materials must be as transparent as possible. In this work, MoOx/ITO/Ag/ITO (MoOx/IAI) thin films with high average transmittance of 79.90% between 400 nm and 900 nm were introduced as the top transparent electrode to explore its influences on optoelectronic properties of the fabricated perovskite solar cells. MoOx has been demonstrated previously as protection from sputtering damage using a conventional ITO top electrode, however it is shown here to provide protection from a sputtered IAI film that provides superior transparency and conductivity and is deposited using more favourable low temperature processing conditions. MoOx and Ag were thermally evaporated and ITO was radio-frequency magnetron sputtered at room temperature. The resulting semi-transparent solar cells showed power conversion efficiency of 12.85% (steady-state efficiency of 11.3%) along with a much-reduced degradation rate as compared to the reference device with only a Ag top electrode. With such a combination of performance and transparency, this work shows great promise in application of perovskite solar cells into window glazing products for building integrated photovoltaic applications (BIPV), powering internet of things (IoT) and combining into tandem solar cells with industrially mature photovoltaic technologies such as silicon and copper indium gallium di-selenide (CIGS).

We report the development of a dual-phase membrane for CO2 separation based on a molten hydroxide liquid phase and a nanoporous yttria-stabilized zirconia solid support phase, termed hydroxide/ceramic dual-phase (HCDP) membranes, that can operate in the flue gas temperature range of 250–650 °C. HCDP membranes demonstrate selectivity for CO2 over N2 greater than 1000 and CO2 permeability of 1.78 ± 0.16 × 10–10 mol m m–2 s–1 Pa–1 (5.32 × 105 barrer) at 550 °C with 20 vol% CO2, which is more than an order of magnitude greater than the best values for dual-phase and polymer membranes reported in the literature. We also demonstrate using three different experimental methods that CO2 absorption by molten hydroxides is reversible in the presence of water vapor at temperatures as low as 300 °C.

Perovskite solar cells (PSCs) have already achieved comparable performance to industrially established silicon technologies. However, high performance and stability must be also be achieved at large area and low cost to be truly commercially viable. The fully printable triple-mesoscopic carbon perovskite solar cell (mCPSC) has demonstrated unprecedented stability and can be produced at low capital cost with inexpensive materials. These devices are inherently scalable, and large-area modules have already been fabricated using low-cost screen printing. As a uniquely stable, scalable and low-cost architecture, mCPSC research has advanced significantly in recent years. This review provides a detailed overview of advancements in the materials and processing of each individual stack layer as well as in-depth coverage of work on perovskite formulations, with the view of highlighting potential areas for future research. Long term stability studies will also be discussed, to emphasise the impressive achievements of mCPSCs for both indoor and outdoor applications.

Complementary electronics has represented the corner stone of the digital era, and silicon technology has enabled this accomplishment. At the dawn of the flexible and wearable electronics age, the seek for new materials enabling the integration of complementary metal-oxide semiconductor (CMOS) technology on flexible substrates, finds in low-dimensional materials (either 1D or 2D) extraordinary candidates. Here, we show that the main building blocks for digital electronics can be obtained by exploiting 2D materials like molybdenum disulfide, hexagonal boron nitride and 1D materials such as carbon nanotubes through the inkjet-printing technique. In particular, we show that the proposed approach enables the fabrication of logic gates and a basic sequential network on a flexible substrate such as paper, with a performance already comparable with mainstream organic technology.

Made available in DSpace on 2021-06-25T15:05:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-04-26 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) U.S. Department of Energy by Lawrence Livermore National Laboratory Higher Education Commission, Pakistan Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Hexavalent chromium (Cr(vi)) is an noxious and highly toxic heavy metal that presents a serious threat to human health if present even in low concentrations in drinking water. Photocatalytic reduction of Cr(vi) to its less toxic Cr(iii) state is a potential strategy to combat Cr(vi) pollution, but the efficiency of the process is low, especially in the absence of hole scavenger organic reagents. To address this issue and prepare efficient photocatalysts for Cr(vi) removal from water, in this study, we explored Prussian blue (PB) as a co-catalyst for improving the photoreduction performance of different high surface area TiO2-based materials (titania or silica-titania nanoparticles and aerogels). The photocatalyst nanomaterials were surface-modified with nanocrystalline PB using the photodeposition route. The PB layer acts as an effective electron acceptor/mediator between the semiconductor photocatalyst and Cr(vi) species. All the PB-modified photocatalysts exhibit higher photocatalytic activity (up to 9 times faster) as compared to the unmodified photocatalysts towards reduction of Cr(vi). Importantly, the PB-modified photocatalysts exhibited high photocatalytic performance (98-99% reduction in 40 min for pH = 5.6 and in 10 min for pH = 3) without addition of organic reagents. The simple approach reported herein can be followed to prepare new PB-photocatalyst systems with improved photocatalytic performance towards Cr(vi) reduction and other target applications. Univ Sao Paulo, Inst Chem Sao Carlos, BR-13560970 Sao Carlos, SP, Brazil Sao Paulo State Univ UNESP, Inst Chem, BR-14800060 Araraquara, SP, Brazil Univ Peshawar, Inst Chem Sci, POB 25120, Peshawar, Pakistan Univ Fed Mato Grosso do Sul, Inst Phys, BR-79070900 Campo Grande, MS, Brazil Sao Paulo State Univ UNESP, Inst Geosci & Exact Sci, Dept Phys, BR-13506970 Rio Claro, SP, Brazil Lawrence Livermore Natl Lab, Phys & Life Sci Directorate, Livermore, CA 94550 USA Sao Paulo State Univ UNESP, Inst Chem, BR-14800060 Araraquara, SP, Brazil Sao Paulo State Univ UNESP, Inst Geosci & Exact Sci, Dept Phys, BR-13506970 Rio Claro, SP, Brazil FAPESP: 2013/24948-3 FAPESP: 2015/22828-6 FAPESP: 2016/10939-0 FAPESP: 2018/01934-0 FAPESP: 2018/19785-1 U.S. Department of Energy by Lawrence Livermore National Laboratory: DEAC52-07NA27344 Higher Education Commission, Pakistan: 9286

Background: The INTREPID study showed improved health status response and lung function in chronic obstructive pulmonary disease (COPD) usual care with single-inhaler fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) vs multiple-inhaler triple therapy (MITT; inhaled corticosteroid+long-acting muscarinic antagonist+long-acting β2-agonist [ICS+LAMA+LABA]). Aim: Evaluate INTREPID outcomes by prior medication strata. Methods: The open-label, phase IV INTREPID study included 3092 intent-to-treat (ITT) COPD patients who received non-ELLIPTA maintenance therapy for ≥16 weeks, had COPD Assessment Test (CAT) score ≥10 and ≥1 moderate/severe exacerbation in prior 3 years, randomised to FF/UMEC/VI 100/62.5/25µg via ELLIPTA or clinician choice of ICS+LAMA+LABA MITT in non-ELLIPTA devices for 24 weeks. Outcomes were analysed by prior medication strata (ICS+LAMA+LABA, ICS+LABA, LAMA+LABA). Results: Odds of CAT response and lung function improvement at Week 24 were statistically significantly greater for FF/UMEC/VI vs MITT in ICS+LAMA+LABA and ICS+LABA strata, and similar in LAMA+LABA stratum (Table). Adverse event incidence was broadly similar by prior medication strata. Conclusions: In usual care, FF/UMEC/VI significantly improved health status response and lung function vs MITT in patients on prior ICS-containing therapy. Method: GSK (206854/NCT03467425).

We aimed to determine the efficacy of multiple micronutrient supplementation on the biomarkers of iron, zinc, and vitamin A status across anthropometric status categories in Vietnamese school children. In this 22-week randomised controlled trial, 347 undernourished, normal weight, or overweight/obese children aged 6–9 years were allocated to receive every school day a multiple micronutrient supplement (10 mg iron, 10 mg zinc, 400 µg vitamin A) or a placebo. Haematological indices; circulating ferritin, zinc, and retinol (corrected for inflammation); and C-reactive protein were measured at baseline and 22 weeks. At week 22, linear mixed models showed that mean corpuscular volume increased by 0.3 fL, serum ferritin by 9.1 µg/L, plasma zinc by 0.9 µmol/L, and plasma retinol by 15%, and the prevalence of zinc deficiency decreased by 17.3% points in the intervention group compared to placebo. No intervention effects were found for other haematological indices, or the prevalence of anaemia. Multiple micronutrient supplementation for 22 weeks improved the biomarkers of zinc and vitamin A status and some biomarkers of iron status, and reduced the prevalence of zinc deficiency in Vietnamese school children.Trial registration: This trial was registered on 06/09/2016 at www.anzctr.org.au as ACTRN12616001245482.

Fabrication of boron carbide (B4C) parts through direct ink writing at room temperature has been demonstrated. The 3D printed B4C parts were made from aqueous, thixotropic ink consisting of B4C particles with a solid loading ranging from 50.0 to 59.3 vol%. The porous B4C parts were infiltrated with molten aluminum (Al) to form a dense B4C-Al cermet. Simple cubic samples with varied spacing between B4C filaments were printed to tailor the density profile within the part. The Rockwell hardness of such parts ranges from 20 to 90 Ra (60 kg) depending on the overall density of the B4C structure. Parts were printed with variable spacings between filaments to systematically determine the upper limit for Al infiltration (800 μm). Elemental analysis revealed a homogenous infiltration both between and within the filaments of 3D printed B4C. Keywords: Additive manufacturing, Boron carbide, Cermet, Direct ink writing

Roll-to-roll (R2R) processing of solution-based Cu2ZnSn(S,Se)4 CZT(S,Se)) solar cells on flexible metal foil is an attractive way to achieve cost-effective manufacturing of photovoltaics. In this work we report the first successful fabrication of solution-processed CZTS devices on a variety of titanium substrates with up to 2.88% power conversion efficiency (PCE) collected on flexible 75 μm Ti foil. A comparative study of device performance and properties is presented aiming to address key processing challenges. First, we show that a rapid transfer of heat through the titanium substrates is responsible for the accelerated crystallisation of kesterite films characterised with small grain size, a high density of grain boundaries and numerous pore sites near the Mo/CZTS interface which affect charge transport and enhance recombination in devices. Following this, wedemonstrate the occurrence of metal ion diffusion induced by thehigh temperature treatment required for the sulfurization of theCZTS stack: Ti4+ ions are observed to migrate upwards to the Mo/CZTS interface whilst Cu1+ and Zn2+ ions diffuse through the Mo layer into the Ti substrate. Finally, residual stress data confirm the good adhesion of stacked materials throughout the sequential solution process. These findings are evidenced by combining electron imaging observations, elemental depth profiles generated by secondary ion mass spectrometry, and x-ray residual stress analysis of the Ti substrate.

The fully printable carbon triple-mesoscopic perovskite solar cell (C-PSC) has already demonstrated good efficiency and long-term stability, opening the possibility of lab-to-fab transition. Modules based on C-PSC architecture have been reported and, at present, are achieved through the accurate registration of each of the patterned layers using screen-printing. Modules based on this approach were reported with geometric fill factor (g-FF) as high as 70%. Another approach to create the interconnects, the so-called scribing method, was reported to achieve more than 90% g-FF for architectures based on evaporated metal contacts, i.e., without a carbon counter electrode. Here, for the first time, we adopt the scribing method to selectively remove materials within a C-PSC. This approach allowed a deep and selective scribe to open an aperture from the transparent electrode through all the layers, including the blocking layer, enabling a direct contact between the electrodes in the interconnects. In this work, a systematic study of the interconnection area between cells is discussed, showing the key role of the FTO/carbon contact. Furthermore, a module on 10 &times, 10 cm2 substrate with the optimised design showing efficiency over 10% is also demonstrated.

Electrically conducting substrates have shown much promise as neuronal scaffolds and in other biologic and biomedical applications where a smart and electrically interactive material is needed. Most materials that are inherently conducting are not suitable for biomedical applications and lack biocompatibility or biostability. On the other hand, biologically stable and compatible materials must first be manipulated, modified, and treated in order to impart the necessary electrical conductivity to the material. Here, the authors have investigated the response of PC-12 cells to two types of conducting carbon-based aerogels with different surface roughness. Results show that carbon-based aerogels support cell adhesion, proliferation, and neurite extension. The effects of surface roughness have also been investigated.

Synthesis of chlorine-free, rare earth oxide aerogels from the lanthanide series was achieved using a modified epoxide-assisted sol-gel method. An ethanolic solution of the hydrated metal nitrate, propylene oxide, and ammonium carbonate was found to gel upon heating to 333 K. Critical point drying of the wet gel in CO2 yielded monolithic aerogels. Most of the aerogels were amorphous as-prepared, but became nano-crystalline after calcination at 923 K in air. The aerogels had high surface areas (up to 150 m2/g), low densities (40–225 mg/cm3), and were photoluminescent.

Boron-doped and defect-engineered graphene aerogels are prepared using triphenyl boron as a boron precursor and subsequent heat treatments. The boron chemistry and concentration in the graphene lat...

Complex shaped boron carbide with carbon (B4C/C) at near-full densities were achieved for the first time using negative additive manufacturing techniques via gelcasting. Negative additive manufacturing involves 3D printing of sacrificial molds used for casting negative copies. B4C powder distributions and rheology of suspensions were optimized to successfully cast complex shapes. In addition to demonstrating scalability of these complex geometries, hierarchically meso-porous structures were also shown to be possible from this technique. Resorcinol-Formaldehyde (RF) polymer was selected as the gelling agent and can also pyrolyze into a carbon aerogel network to act as the sintering aid for B4C. Due to the highly effective distribution of in situ carbon for the B4C matrix, near-full sintered density of 97–98% of theoretical maximum density was achieved. Keywords: Boron carbide, Gelcasting, Negative additive manufacturing, Resorcinol formaldehyde, Sintering

Bactrocera cucumis is a lesser known native fruit fly in Australia. There are 44 reported hosts including cucurbits, papaws and tomatoes with a strong preference for cucurbits. Adult flies are not attracted to the known male lures such as cuelure, methyl eugenol or zingerone. They are weakly attracted to protein lures and a recently discovered cucumber volatile. For this reason, surveillance for this fruit fly remains problematic. Its range is predominantly coastal and appears to be centred north of Rockhampton in Queensland. It is known in the Northern Territory, Queensland and in New South Wales north of 29 o S latitude. Internationally, it is not reported in any Pacific countries or other parts of the world.

We report 3D printing of a ‘pure’ thermal cure cyanate ester for the fabrication of robust 3D printed structures through the formulation, tailoring and post processing of a custom ‘ink’ for Direct Ink Writing. Printed structures exhibit impressive thermo-oxidative stability, mechanical response.

The use of additive manufacturing to 3D print aerogels has the potential to impact several important technologies such as energy storage, catalysis, and desalination. While there has been a great deal of focus on graphene aerogels, reports of 3D printed conventional carbon aerogels (CAs) are sparse. Activated CAs are particularly compelling because in addition to having a lower cost than a comparable graphene aerogel, they can achieve much higher surface areas (>3000 m2 g−1). Herein we report a 3D printable ink based on traditional resorcinol–formaldehyde sol–gel chemistry that can produce a final activated carbon aerogel with surface areas approaching 2000 m2 g−1 and good electrical conductivities (∼200 S m−1). Direct ink writing (DIW) is used to then fabricate electrodes, which demonstrate excellent electrochemical properties with a high specific capacitance of 215 F g−1 at 1 A g−1 and 83% capacitive retention at higher current densities (10 A g−1). The DIW electrode significantly outperformed its bulk counterpart and provides an example of how one can use 3D printed aerogel electrodes to overcome mass transport limitations and boost energy storage performance.

With an increasing demand for energy and concerns about the environment, scientists are trying to find a better way to generate green energy and store the generated energy efficiently. Biowaste could be an attractive source for the preparation of active materials for energy storing devices. In this project, a shell of pomegranate was used to prepare high surface area carbon for supercapacitor applications. The dry powder of pomegranate was chemically activated using various ratios of pomegranate and activating agent to produce carbon with a range of properties. The unactivated pomegranate-based carbon's surface area was 40 m2/g, which improved to 1459, 1737, and 2189 m2/g upon chemical activation using 1:1, 1:2, and 1:3 ratios of pomegranate: activating agent, respectively. The energy storage capacity was calculated using galvanostatic charge-discharge measurements, and the highest specific capacitance of 190 F/g at 1 A/g was observed for PG-2 (1:2 ratio of pomegranate: activating agent) carbon. Using the electrode, the symmetric supercapacitor devices were fabricated utilizing various electrolytes (aqueous, organic, and ionic liquid electrolytes). The highest energy density of 8.8, 39, and 68 Wh/kg were obtained for aqueous, organic, and ionic liquid electrolytes, respectively. On the other hand, the highest power density of 3950, 8943, and 11,316 W/kg have been achieved for the pomegranate-based carbon in aqueous, organic, and ionic liquid electrolytes, respectively. Our research suggests that pomegranate-based carbon could be an attractive material for the fabrication of energy storage devices.

Carbon aerogels (CAs) are a unique class of high surface area materials derived by sol–gel chemistry. Their high mass-specific surface area and electrical conductivity, environmental compatibility, and chemical inertness make them very promising materials for many applications, such as energy storage, catalysis, sorbents, and desalination. Since the first CAs were made via pyrolysis of resorcinol–formaldehyde (RF)-based organic aerogels in the late 1980s, the field has really grown. Recently, in addition to RF-derived amorphous CAs, several other carbon allotropes have been realized in aerogel form: carbon nanotubes (CNTs), graphene, graphite, and diamond. Furthermore, the popularity of graphene aerogels has inspired research into aerogels made of a host of graphene analog materials (e.g., boron nitride, transition metal dichalcogenides, etc.), with potential for an even wider array of applications. Finally, the development of three-dimensional-printed aerogels provides the potential for CAs to have an even broader impact on energy-related technologies. Here, we will present recent work covering the novel synthesis of RF-derived, CNT, graphene, graphite, diamond, and graphene analog aerogels.

The gas sensing characteristics of porous tungsten disulfide (WS 2 ) aerogel are investigated. The sensor is fabricated by integrating WS 2 aerogel onto a low power polycrystalline silicon microheater platform to provide control over the operating temperature. The WS 2 aerogel is characterized by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and thermal gravimetric analysis. The sensing performances of the WS 2 aerogel-based sensor to NO 2 , O 2 , NH 3 , H 2 , and humidity are investigated, indicating a p-type behavior. The optimum sensing temperature is found to be about 250 °C, when considering sensitivity, power consumption and response time. The role of O 2 in the sensor performance is probed and is found to be helpful for enhancing the sensitivity and recovery of the sensor in H 2 , humidity and NH 3 .

Nooreen Shaikh,1,2 Malcolm Johnson,3 David A Hall,4 Kian Fan Chung,1,2 John H Riley,3 Sally Worsley,5 Pankaj K Bhavsar1,2 1Experimental Studies, National Heart and Lung Institute, Imperial College London, 2Biomedical Research Unit, Royal Brompton and Harefield NHS Trust, London, 3Respiratory Global Franchise, GlaxoSmithKline, Uxbridge, 4Fibrosis and Lung Injury Development Planning Unit, GlaxoSmithKline, Stevenage, 5Respiratory Research & Development, GlaxoSmithKline, Uxbridge, UK Background: Intracellular mechanisms of action of umeclidinium (UMEC), a long-acting muscarinic receptor antagonist, and vilanterol (VI), a long-acting β2-adrenoceptor (β2R) agonist, were investigated in target cells: human airway smooth-muscle cells (ASMCs). Materials and methods: ASMCs from tracheas of healthy lung-transplant donors were treated with VI, UMEC, UMEC and VI combined, or control compounds (salmeterol, propranolol, ICI 118.551, or methacholine [MCh]). Cyclic adenosine monophosphate (cAMP) was measured using an enzyme-linked immunosorbent assay, intracellular free calcium ([Ca2+]i) using a fluorescence assay, and regulator of G-protein signaling 2 (RGS2) messenger RNA using real-time quantitative polymerase chain reaction. Results: VI and salmeterol (10–12–10–6 M) induced cAMP production from ASMCs in a concentration-dependent manner, which was greater for VI at all concentrations. β2R antagonism by propranolol or ICI 118.551 (10–12–10–4 M) resulted in concentration-dependent inhibition of VI-induced cAMP production, and ICI 118.551 was more potent. MCh (5×10–6 M, 30 minutes) attenuated VI-induced cAMP production (P

Actinomycetes are a diverse family of filamentous bacteria that produce a plethora of natural products relevant for agriculture, biotechnology and medicine, including the majority of the antibiotics we use in the clinic. Rather than as free-living bacteria, many actinomycetes have evolved to live in symbiosis with among others plants, fungi, insects and sponges. As a common theme, these organisms profit from the natural products and enzymes produced by the actinomycetes, for example, for protection against pathogenic microbes, for growth promotion or for the degradation of complex natural polymers such as lignocellulose. At the same time, the actinomycetes benefit from the resources of the hosts they interact with. Evidence is accumulating that these interactions control the expression of biosynthetic gene clusters and have played a major role in the evolution of the high chemical diversity of actinomycete-produced secondary metabolites. Many of the biosynthetic gene clusters for antibiotics are poorly expressed under laboratory conditions, but they are likely expressed in response to host-specific demands. Here, we review the environmental triggers and cues that control natural product formation by actinomycetes and provide pointers as to how these insights may be harnessed for drug discovery.

Surface lubricity on TiO2-coated galvanised steels can be controlled by solution depositing perfluorooctanoic (C8), lauric (C12) or stearic (C18) acids to avoid lubricating oils/emulsions or substrate pre-etching to remove surface oxide that add cost and waste. Water contact angles reveal increased surface hydrophobicity on coated samples that correlate with linear friction testing, suggesting water contact angle can be used to screen lubricity compounds. Linear friction testing shows that C12 and C18 lower the coefficient of friction (μ) by 50–60% compared with uncoated substrates whilst C8 drops μ from 0.31 to 0.22. Surfaces have been characterised by X-ray photoelectron spectroscopy, scanning electron microscopy and atomic force microscopy, whilst infrared confirms that as-deposited coatings contain physisorbed and deprotonated acids chemisorbed through esters and thermal gravimetric analysis confirms increasing loadings from C8 to C12 to C18. Surface washing removes physisorbed material and lowers μ by increasing surface organisation and alkyl chain packing that enhances frictional energy dissipation through steric quenching. Copyright © 2017 John Wiley & Sons, Ltd.

The importance of the oxidation state of an oxidizer and its impact on gaseous oxygen and total gas production in nanocomposite thermite combustion was investigated by probing the reaction and ignition properties of aluminum nanoparticles (Al-NPs) with both cupric oxide (CuO) and cuprous oxide (Cu2O) nanoparticles. The gas release and ignition behavior of these materials were tested with >105 K/s temperature jump (T-jump) heating pulses in a high temporal resolution time-of-flight mass spectrometer (ToF-MS) as well as in an argon environment. Reactivity was tested using a constant volume combustion cell with simultaneous pressure and optical measurements. A variety of Cu2O particle sizes ranging from 200 to 1500 nm were synthesized and found to release oxygen at ∼1200 K, which is higher than the values found for a variety of CuO particle sizes (∼1000 K). Both oxides were found to ignite around 1000 K, which implies a consistent ignition mechanism for both through a condensed phase pathway. The higher oxid...

Understanding the mechanisms that promote the assembly and maintenance of host-beneficial microbiomes is an open problem. Empirical evidence supports the idea that animal and plant hosts can combine ‘private resources’ with the ecological phenomenon known as ‘community bistability’ to favour some microbial strains over others. We briefly review evidence showing that hosts can: (i) protect the growth of beneficial strains in an isolated habitat, (ii) use antibiotics to suppress non-beneficial, competitor strains, and (iii) provide resources that only beneficial strains are able to translate into an increased rate of growth, reproduction, or antibiotic production. We then demonstrate in a spatially explicit, individual-based model that these three mechanisms act similarly by selectively promoting the initial proliferation of preferred strains, that is, by acting as a private resource. The faster early growth of preferred strains, combined with the phenomenon of ‘community bistability,’ allows those strains to continue to dominate the microbiome even after the private resource is withdrawn or made public. This is because after a beneficial colony reaches a sufficiently large size, it can resist invasion by parasites without further private support from the host. We further explicitly model localized microbial interactions and diffusion dynamics, and we show that an intermediate level of antibiotic diffusion is the most efficient mechanism in promoting preferred strains and that there is a wide range of parameters under which hosts can promote the assembly of a self-sustaining defensive microbiome. This in turn supports the idea that hosts readily evolve to promote host-beneficial defensive microbiomes., Author summary Host-associated microbiomes are complex communities, harbouring a great diversity of beneficial, neutral, or harmful species. Microbiome composition can have a significant effect on the health status and fitness of the host, and thus host species are selected to evolve mechanisms that favour the assembly of certain kinds of microbiomes over others. As we demonstrate, both by reviewing the literature and by using a detailed, spatially explicit, mathematical model, a host species can employ several cost-effective mechanisms to promote the establishment of beneficial bacteria, for example antibiotic producers, and to prevent the invasion of harmful microbes. These mechanisms include the host providing private resources in the form of a food source or inhabitable space that the preferred antibiotic-producing species are able to use to their advantage against species that are harmful to the host. After an antibiotic-producing species establishes itself with the help of the host, its colony is now self-sustaining, even if host resources now become publicly available, and can provide a reliable safeguard against parasites.

Polyhexamethylene biguanide (PHMB) is a broad-spectrum antiseptic which avoids many efficacy and toxicity problems associated with antimicrobials, in particular, it has a low risk of loss of susceptibility due to acquired antimicrobial resistance. Despite such advantages, PHMB is not widely used in wound care, suggesting more research is required to take full advantage of PHMB&rsquo, s properties. We hypothesised that a nanofibre morphology would provide a gradual release of PHMB, prolonging the antimicrobial effects within the therapeutic window. PHMB:polyurethane (PU) electrospun nanofibre membranes were prepared with increasing PHMB concentrations, and the effects on antimicrobial activities, mechanical properties and host cell toxicity were compared. Overall, PHMB:PU membranes displayed a burst release of PHMB during the first hour following PBS immersion (50.5&ndash, 95.9% of total released), followed by a gradual release over 120 h (&le, 25 wt % PHMB). The membranes were hydrophilic (83.7&ndash, 53.3&deg, ), gradually gaining hydrophobicity as PHMB was released. They displayed superior antimicrobial activity, which extended past the initial release period, retained PU hyperelasticity regardless of PHMB concentration (collective tensile modulus of 5&ndash, 35% PHMB:PU membranes, 3.56 &plusmn, 0.97 MPa, ultimate strain, &gt, 200%) and displayed minimal human cell toxicity (&lt, 25 wt % PHMB). With further development, PHMB:PU electrospun membranes may provide improved wound dressings.

Effectiveness studies complement conventional randomised controlled trials by providing a holistic view of treatments in the setting of usual clinical practice. We present the protocol for the ongoing INTREPID (INvestigation of TRelegy Effectiveness: usual PractIce Design; ClinicalTrials.gov identifier: NCT03467425) study, a randomised, open-label, 24-week effectiveness study of once-daily fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI; Trelegy) delivered by the ELLIPTA inhaler versus non-ELLIPTA multiple-inhaler triple therapy in patients with chronic obstructive pulmonary disease (COPD) in usual practice settings. INTREPID was designed to provide evidence of FF/UMEC/VI effectiveness in patients with COPD managed in routine healthcare systems across multiple European countries. Between study initiation and end-of-study visits, patients will receive their medication and care as they would ordinarily receive it, from their usual healthcare provider at their usual healthcare centre. Study-specific intervention will be minimal. The primary end-point will be the proportion of COPD assessment test (CAT) responders, defined as a clinically meaningful improvement from baseline of ≥2 units, at week 24. The CAT was chosen as it provides health status information relevant to patients, physicians, health technology agencies and payers. Lung function (forced expiratory volume in 1 s) and critical inhaler errors will also be assessed in a subgroup of patients. The strengths and weaknesses of the protocol and some of the challenges associated with conducting this multicountry study, such as differences in healthcare systems and treatment practices across sites, will also be discussed., The INTREPID COPD study is investigating the real-world effectiveness of fluticasone furoate/umeclidinium/vilanterol delivered by ELLIPTA versus multiple-inhaler triple therapies in Europe. This article presents the protocol and discusses effectiveness studies in COPD. http://bit.ly/2ZzBAo3

Poly(4,4′-oxydiphenylene-oxydiphthalimide) (POO) was thermally treated at 773 K for 1, 15 and 60 min under argon atmosphere resulting in free-standing films with intermingled characteristics between polymer and carbon-rich derivatives. Degradative thermal analysis performed by pyrolysis-gas chromatography/mass spectroscopy (Py-GC/MS) revealed CO2 among the major products of thermal decomposition which according to electron paramagnetic resonance (EPR) passed through a radical process. X-ray diffraction (XRD) revealed thermal treated samples with semicrystalline organization that was attributed to the development of lamellae structure. Moreover, Atomic force microscopy (AFM) showed an increase in the roughness of the samples that acquired pronounced roughcast-like surface. Hence, there was an enhancement of mechanical strength and dielectric permittivity. From the data collected a mechanism of thermal decomposition was proposed.

A MoS2/graphene hybrid aerogel synthesized with two-dimensional MoS2 sheets coating a high surface area graphene aerogel scaffold is characterized and used for ultrasensitive NO2 detection. The combination of graphene and MoS2 leads to improved sensing properties with the graphene scaffold providing high specific surface area and high electrical and thermal conductivity and the single to few-layer MoS2 sheets providing high sensitivity and selectivity to NO2. The hybrid aerogel is integrated onto a low-power microheater platform to probe the gas sensing performance. At room temperature, the sensor exhibits an ultralow detection limit of 50 ppb NO2. By heating the material to 200 °C, the response and recovery times to reach 90% of the final signal decrease to