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The inevitability to reduce CO2 emissions to avoid preventable climate change is widely being yelped. To minimise the impact of rapidly changing climate, this paper presents novel research findings and contributes to developing electrochromic argon gas-filled glazed smart windows retrofitted to the building with IoT based transparency control. In this, the comparative analyses of the daylighting, electrical lighting, solar heat gain, and space-heating load of the building using the dynamic thermal and electric lighting modelling methods based on real weather temperatures are presented. The daylighting analysis results implicate that the building with electrochromic argon gas-filled smart windows reduced 19% of daylight illuminance during summer months compared with the building retrofitted with double air-filled glazed windows daylight factor remains consistent. As such, the solar heat gains analysis results implicate at least 50 % annual solar heat gain reduction predicted in the building with electrochromic argon gas-filled smart windows in comparison to double air-filled windows. This leads to the conclusion of the space-heating energy analysis that implicates the highest contribution to the space heating demand is the solar heat gain caused by double air-filled glazed windows. The results confirm that the LED artificial electric lighting system requires fewer fittings and thus total power load compared to the fluorescent lighting system, throughout the year, to the building with electrochromic argon gas-filled glazed smart windows. The daylight controls are linked to the electrochromic argon gas-filled glazed smart windows, so they only operate when the glazing is tinted, or the daylight level drops below a set level; this will reduce the energy usage and also lower the space heating of the room.

The aim of this report is to present the root cause analysis on failed patient‐specific quality assurance (QA) measurements of pencil beam scanning (PBS) protons; referred to as PBS‐QA measurement. A criterion to fail a PBS‐QA measurement is having a 94%, 94 to >88%, and 3% per mm dose gradient with respect to depth on the failed measurements. We utilized a 2D/three‐dimensional (3D) gamma index analysis toolkit to investigate the effect of depth dose gradient. By utilizing this 3D toolkit, 43.1% of the failed measurements were improved. A feature among measurements that remained sub‐optimal after re‐analysis was a sharp >3% per mm lateral dose gradient that may not be well handled using the detector size of 5.0 mm in‐diameter. An analysis of the sampling of finite size detectors using one‐dimensional (1D) error function showed a large dose deviation at locations of low‐dose areas between two high‐dose plateaus. User error, large depth dose gradient, and the effect of detector size are identified as root causes. With the mitigation of the root causes, the goals of patient‐specific QA, specifically detecting actual deviation of beam delivery or identifying limitations of the dose calculation algorithm of the treatment planning system, can be directly related to failure of the PBS‐QA measurements.

Phosphate shortages and the ensuing pressures on food security have led to an interest in processed sewage sludge as a substitute for commercial fertilisers. The presence of heavy metals in this nutrient source causes concerns around environmental release and pollution. This work builds towards a resin-in-pulp sludge detoxification process. It showcases the kinetic and thermodynamic adsorption capabilities of the ion-exchange resins C107E (carboxylic acid functionality), MTS9301 (iminodiacetic acid) and TP214 (thiourea), with respect to Cu(II), Fe(II), Pb(II) and Zn(II), within a simulated sewage sludge weak acid (acetate) leachate. The isotherms produced in this complex system were quite different to those generated when single metals were investigated in isolation, with desorption of lower affinity species clearly observed at higher equilibrium concentration values. Mixed-metal isotherm data were fitted to common two-parameter isotherm models and also a novel modified Langmuir model, which better accounted for the effects of desorption and competition. Kinetic data were also fit to common two-parameter models; results suggesting the system was likely film diffusion-controlled and followed pseudo-2nd-order kinetics. C107E displayed rapid adsorption of lead (t

A series of conjugated microporous polymers (CMPs) based on bromophenol blue (BB) and bromocresol green (BG) have been synthesized via Sonogashira-Hagihara cross coupling reaction with surface areas up to 747 m2/g. The CMPs can be post functionalized with chlorosulfonic acid to yield corresponding sulfonated polymers with high acidity up to 7.67 mmol/g. The sulfonated CMPs showed excellent catalytic activity for the esterification of free fatty acids and transesterification of various vegetable oils and waste cooking oil as well as excellent reusability up to 4 consecutive runs without significant activity loss. These sulfonated CMPs have potential applications as recyclable acid catalysts for environmentally friendly biodiesel production from waste cooking oil.

Abstract This work aims to contribute to addressing the global challenge of recycling and valorising spent potlining; a hazardous solid waste product of the aluminium smelting industry. This has been achieved using a simple two-step chemical leaching treatment of the waste, using dilute lixiviants, namely NaOH, H2O2 and H2SO4, and at ambient temperature. The potlining and resulting leachate were characterised by spectroscopy and microscopy to determine the success of the treatment, as well as the morphology and mineralogy of the solid waste. This confirmed that the potlining samples were a mixture of contaminated graphite and refractory materials, with high variability of composition. A large quantity of fluoride was solublised by the leaching process, as well as numerous metals, some of them toxic. The acidic and caustic leachates were combined and the aluminium and fluoride components were selectively extracted, using a modified ion-exchange resin, in fixed-bed column experiments. The resin performed above expectations, based on previous studies, which used a simulant feed, extracting fluoride efficiently from leachates of significantly different compositions. Finally, the fluoride and aluminium were coeluted from the column, using NaOH as the eluent, creating an enriched aqueous stream, relatively free from contaminants, from which recovery of synthetic cryolite can be attempted. Overall, the study accomplished several steps in the development of a fully-realised spent potlining treatment system. Graphic Abstract

Hydrophilic hypercrosslinked porous polymer networks were synthesised from 2,2-biphenol (HHCP1) and bisphenol A (HHCP2) monomers, which were assessed for remediation of highly fluoridated water. The networks were hydrophilic and the hypercrosslinking radically altered the acidity of protonation sites within the polymeric scaffolds. The polymers were metallated to produce novel, hybrid Ca-loaded adsorbents. The metal-loading affected the electron distribution of the quinonoid structures formed during polymerisation. HHCP1 had a greater exchange capacity (6.34 ± 0.17 mmol g−1) and adsorbed more Ca2+, yet retained much of its original surface area, whereas HHCP2 was rendered non-porous upon metallation. Ca-loading included covalent interactions and formation of crystalline CaCO3 (vaterite), from preferential CO2 binding under ambient conditions. Both networks were effective defluoridating media, with Ca-loaded HHCP1 exhibiting a capacity among the highest yet reported for any extractant (267 ± 34 mg g−1). HHCP2-Ca had a lower capacity of 96.2 ± 10 mg g−1, but faster uptake kinetics and was more effective at lower concentrations, attributed to stronger binding interactions. Crystalline CaF2 (fluorite) was the dominant fluoride species formed, from both vaterite and covalently bound Ca. The networks could be used in a dynamic column system, extracted fluoride in the presence of multiple coexisting anions and were regenerable, with a potential pathway demonstrated for recovery of the adsorbed fluoride.

Sulfonated hyper-cross-linked polymers based on 4,4′-bis(chloromethyl)-1,1′-biphenyl (BCMBP) were synthesized via metal-free (SHCP-1) and conventional Lewis acid-catalyzed (SHCP-2) Friedel–Crafts alkylation routes. The sulfonated polymers possessed BET surface areas in excess of 500 m2·g–1. SHCP-1 was investigated for its ability to extract Sr and Cs ions from aqueous solutions via the ion-exchange reaction of the sulfonic acid moiety. Equilibrium uptake data could be accurately modeled by the Dubinin–Radushkevich isotherm, with maximum calculated loading values of 95.6 ± 2.8 mg·g–1 (Sr) and 273 ± 37 mg·g–1 (Cs). Uptake of both target ions was rapid, with pseudo second-order rate constants calculated as 7.71 ± 1.1 (×10–2) for Sr and 0.113 ± 0.014 for Cs. Furthermore, the polymer was found to be highly selective toward the target ions over large excesses of naturally occurring competing metal ions Na, K, Mg, and Ca. We conclude that hyper-cross-linked polymers may offer intrinsic advantages over other adsorbents for the remediation of aqueous Sr and Cs contamination.

Herein, we report a simple method for the preparation of cross-linked polymer of intrinsic microporosity (PIM-1)/Materials Institute Lavoisier chromium (III) terephthalate [MIL-101(Cr)] monoliths which involves direct impregnation of PIM-1 with MIL-101(Cr) powder by physical mixing in tetrachloroethane solvent. This procedure yields monoliths with high metal–organic framework (MOF) loading weight percentages of up to 80 wt% of MIL-101 powder with little loss of composite mechanical strength. From the nitrogen adsorption isotherms, it was observed that the PIM-1/80 wt% MIL-101(Cr) had good retention of MOF filler surface area and accessibility of its micropores with nearly no pore blocking effects. The hydrogen adsorption was also not far from the estimated hydrogen uptake capacity based on the MIL-101 weight percentage estimation. As a consequence of the highly porous nature of the hybrid material, PIM-1/MIL-101(Cr) composite has been considered as a promising material for inclusion in hybrid hydrogen storage cylinders. Moreover, these composites provided better handling compared to the crystalline powder MOFs without compromising the properties of MOF.

Microporous materials are predominantly formed as insoluble powders which means that they can be difficult to process. Here we report a new class of solvent-dispersible porous polymers synthesised by reversible addition–fragmentation chain transfer mediated polymerisation-induced self-assembly (RAFT-mediated PISA), formed from the polymerisation of divinylbenzene and fumaronitrile using a poly(ethylene glycol) macromolecular chain transfer agent (PEG macro-CTA). The particles have a dual morphology consisting of smaller spheres of 24–29 nm in diameter aggregated into larger particles of 204–262 nm in diameter. Gas sorption analysis showed the particles to have BET surface areas of 274 to 409 m2 g−1 with internal pore sizes centred around 1.8 nm and further larger pores arising from the sphere packing of the aggregates. The particles were found to be photoluminescent (emission λmax = 326 nm) when exposed to UV light which could be quenched by the addition of nitroaromatic compounds, for example, 99% of the emission was quenched in the presence of 38 ppm picric acid.

The methanol carbonylation catalyst, cis-[Rh(CO)2I2]–, has been heterogenised within a dispersible microporous polymer support bearing cationic functionality. The microporous polymer has a core-shell structure in which the porous and insoluble core (a co-polymer of divinylbenzene and 4-vinylpyridine) is suspended in solution by long hydrophilic poly(ethylene glycol) chains, allowing a stable suspension of the nanoparticles to form. Incorporation of 4-vinylpyridine as a co-monomer allows post-synthetic modification to generate N-methylpyridinium sites for electrostatic attachment of the anionic rhodium(I) complex. The dispersibility of the polymer-supported catalyst material facilitates the use of in situ transmission IR spectroscopy to obtain kinetic data for the oxidative addition of iodomethane to immobilised cis-[Rh(CO)2I2]– (the rate-limiting step of the carbonylation cycle). Remarkably, the oxidative addition proceeds faster than for the homogeneous system (Bu4N+ counter-ion, CH2Cl2, 25 °C). The polymer-supported catalyst was found to be active for methanol carbonylation, with a turnover frequency similar to that of the homogeneous analogue under the same conditions (10 bar CO, MeI/MeOH/CHCl3, 120 °C). The supported catalyst is easily recovered and is shown to maintain comparable activity upon recycling.

Functionalized hypercrosslinked polymers (HCPs) with surface areas between 213 and 1124 m2/g based on a range of monomers containing different chemical moieties were evaluated for CO2 capture using a pressure swing adsorption (PSA) methodology under humid conditions and elevated temperatures. The networks demonstrated rapid CO2 uptake reaching maximum uptakes in under 60 s. The most promising networks demonstrating the best selectivity and highest uptakes were applied to a pressure swing setup using simulated flue gas streams. The carbazole, triphenylmethanol and triphenylamine networks were found to be capable of converting a dilute CO2 stream (&gt, 20%) into a concentrated stream (&gt, 85%) after only two pressure swing cycles from 20 bar (adsorption) to 1 bar (desorption). This work demonstrates the ease with which readily synthesized functional porous materials can be successfully applied to a pressure swing methodology and used to separate CO2 from N2 from industrially applicable simulated gas streams under more realistic conditions.

We introduce fluoride-selective anion exchange resin sorbents as sensitisers into membranes for water-gated field effect transistors (WGTFTs). Sorbents were prepared via metal (La or Al)-loading of a commercial macroporous aminophosphonic acid resin, PurometTM MTS9501, and were filled into a plasticised poly(vinyl chloride) (PVC) phase transfer membrane. We found a potentiometric response (membrane potential leading to WGTFT threshold shift) to fluoride following a Langmuir&ndash, Freundlich (LF) adsorption isotherm with saturated membrane potential up to ~480 mV, extremely low characteristic concentration c1/2 = 1/K, and picomolar limit of detection (LoD), even though ion exchange did not build up charge on the resin. La-loading gave a superior response compared to Al-loading. Membrane potential characteristics were distinctly different from charge accumulating sensitisers (e.g., organic macrocycles) but similar to the Cs+ (cation) selective ion-exchanging zeolite mineral &lsquo, mordenite&rsquo, We propose a mechanism for the observed threshold shift and investigate interference from co-solutes. Strong interference from carbonate was brought under control by &lsquo, diluting&rsquo, metal loading in the resin. This work sets a template for future studies using an entirely new &lsquo, family&rsquo, of sensitisers in applications where very low limit of detection is essential such as for ions of arsenic, mercury, copper, palladium, and gold.

MXenes are a recently discovered class of two-dimensional materials that have shown great potential as electrodes in electrochemical energy storage devices. Despite their promise in this area, MXenes can still suffer limitations in the form of restricted ion accessibility between the closely spaced multistacked MXene layers, causing low capacities and poor cycle life. Pillaring, a strategy where a secondary species is inserted between layers, has been used to increase interlayer spacings in clays with great success, but has had limited application in MXenes. We report a new amine-assisted pillaring methodology that successfully intercalates silica-based pillars between Ti3C2 layers. Using this technique, the interlayer spacing can be controlled with the choice of amine and calcination temperature, up to a maximum of 3.2 nm, the largest interlayer spacing reported for an MXene. Another effect of the pillaring is a dramatic increase in surface area, achieving BET surface areas of 235 m2 g-1, a sixty-fold increase over the unpillared material and the highest reported for MXenes using an intercalation-based method. The intercalation mechanism was revealed by different characterisation techniques, allowing the surface chemistry to be optimised for the pillaring process. The porous MXene was tested for Na-ion battery applications, and showed superior capacity, rate capability and remarkable stability compared with non-pillared materials, retaining 98.5% capacity between the 50th and 100th cycles. These results demonstrate the applicability and promise of pillaring techniques applied to MXenes, providing a new approach to optimising their properties for a range of applications. Porous MXenes are very promising materials for a range of applications including energy storage, conversion, catalysis and gas separations.

Poor air quality inside vehicles and its impact on human health is an issue requiring attention, with drivers and passengers facing levels of air pollution potentially greater than street-side outd...

Polymers of intrinsic microporosity (PIMs) are currently attracting interest due to their unusual combination of high surface areas and capability to be processed into free-standing films. However, there has been little published work with regards to their physical and mechanical properties. In this paper, detailed characterisation of PIM-1 was performed by considering its chemical, gas adsorption and mechanical properties. The polymer was cast into films, and characterised in terms of their hydrogen adsorption at −196 °C up to much higher pressures (17 MPa) than previously reported (2 MPa), demonstrating the maximum excess adsorbed capacity of the material and its uptake behaviour in higher pressure regimes. The measured tensile strength of the polymer film was 31 MPa with a Young’s modulus of 1.26 GPa, whereas the average storage modulus exceeded 960 MPa. The failure strain of the material was 4.4%. It was found that the film is thermally stable at low temperatures, down to −150 °C, and decomposition of the material occurs at 350 °C. These results suggest that PIM-1 has sufficient elasticity to withstand the elastic deformations occurring within state-of-the-art high-pressure hydrogen storage tanks and sufficient thermal stability to be applied at the range of temperatures necessary for gas storage applications.

A large predicted increase in population growth and dwindling phosphate resources has led to sewage sludge being an attractive alternative to commercial fertilisers. Among other contaminants, heavy metals are a barrier to unrestricted use of sewage sludge or sewage sludge ash as a phosphate source. This study will focus on the equilibrium isotherm behaviours of Cu2+, Fe2+, Pb2+ and Zn2+ towards C107E, MTS9301 and TP214 resins within acetic acid media, fit to the two parameter Freundlich, Langmuir, Temkin and Dubinin-Radushkevich (D-R) isotherm models. C107E and MTS9301 were both found to have comparable monolayer capacities for Cu2+ and Fe2+ (5 ± 1 vs 4.3 ± 0.7 mmol·g−1 and 2.1 ± 0.8 vs 2.3 ± 0.8 mmol·g−1 for Cu2+ and Fe2+, respectively). The Freundlich model implied heterogeneous binding for Pb2+ and Zn2+ adsorption to C107E and MTS9301. The monolayer capacities of MTS9301 for lead and zinc were calculated as 2.1 ± 0.2 mmol·g−1 and 3 ± 1 mmol·g−1, respectively. MTS9301 returned larger D-R free energy values than C107E, with the largest difference being Zn2+, displaying energies of 14.0 and 5.5 kJ·mol−1, respectively. TP214 displayed the lowest capacity for metals with Fe2+, Pb2+ and Zn2+ returning D-R energy values closer to physisorption mechanisms (6.0 ± 0.5, 7.1 ± 0.4 and 7.8 ± 0.5 kJ·mol−1, respectively), with copper returning a D-R energy relating to chemisorption (17 ± 1 kJ·mol−1). Overall, it was observed that the similarity of the C107E functionality to the free acetate anion led to the highest level of hindrance, seconded by the interaction between Fe2+, Pb2+ and Zn2+ to TP214, while copper displayed strong interaction with TP214 and MTS9301 displayed little or no hindrance by the acetate complexes in solution, with solution phase complexes affecting the homogeneity of binding within any ion exchange reaction.

A dispersible porous polymer (PEG113 -b-DVB800 -co-AA200 ) based on the controlled radical polymerization of divinylbenzene and acrylic acid with a poly(ethylene glycol) (PEG) macrochain transfer agent (macro-CTA) is synthesized and postsynthetically modified with anthracene. This blue-emitting porous polymer is used to encapsulate the yellow-emitting fluorophore rhodamine B into its core, resulting in a white-light emitting dispersion with a quantum yield of 38% and commission internationale de l'eclairage coordinates of (X = 0.33, Y = 0.32).

Homelessness is a social condition that people enter, and sometimes leave, through a number of social and personal causes, but whatever the causes of their entry into this condition, the homeless constitute a social formation systematically deprived of the rewards, security, and empowerment that society offers its more "normal" members. The shelter in which these homeless men spend their nights is part of a Protestant church, yet is clearly separated from it. It was built onto the back of the church, is invisible from the front and the main entrance, and the men have to approach it through a back alley out of sight of the regular churchgoers. The consistent viewing preference of the smoking lounge men was for violent, R-rated movies, which they borrowed from the local library. At the library from which the men borrow the videos, the librarian confirmed that the homeless consistently chose violent films to watch.

We present a high-speed and broadband time-domain terahertz spectroscopy system based on a single bidirectionally mode-locked fiber laser. This fiber ring laser generates two optical pulse trains having slightly different repetition rates and a slowly varying repetition rate difference in free running mode, eliminating the need for servo locking electronics. Using plasmonics-enhanced photoconductive antennas for terahertz emission and detection, the system generates sufficient output photocurrent on the detector for self-triggering. Acquired spectral data show agreement with the HITRAN water absorption line data up to 1.5 THz. The use of a single compact fiber laser system with simple data acquisition demonstrates the feasibility of a portable time-domain terahertz spectroscopy system with significant reduction in size, weight, and power consumption.

We report a self-triggered single-laser THz spectroscopy system with no moving parts or locking electronics. The simplicity of this architecture demonstrates the possibility of portable THz spectrometers with smaller size, weight and power requirements.

Microporous polymers are covalently bound, entirely organic materials which possess very high surface areas. These materials have been intensively studied within recent years and various interesting properties and possible applications have been discovered and described. This review article starts with the question, what makes microporous polymers special and are there certain features which differentiate them from other microporous materials? Indeed, there are some special structural and functional features found in microporous polymers which make them really unique and merit further exploration. We focus here on microporous polymers which are solution-processable, can be produced as thin films on electrodes by oxidative polymerizations, are π-conjugated organic semiconductors, or which provide the possibility to introduce and exploit distinct functional groups in an otherwise non-functional highly porous environment. Emerging applications for these microporous polymers which make explicit use of these unique features are further presented.

Two M

Conjugated microporous polymeric networks possessing thioxanthone groups were reported to initiate free radical and cationic polymerizations of vinyl monomers and cyclic ethers, respectively, under visible light irradiation. These new classes of Type II macrophotoinitiators with high porosity having large BET surface area of 500–750 m2 g–1 were prepared through different cross-coupling processes. Polymerizations are successfully achieved in conjugation with several co-initiators benefiting from hydrogen abstraction or electron transfer reactions stimulated by either visible light or natural sunlight irradiation. Photopolymerizations conducted by using knitted photoinitiators show better conversion and rate of polymerization than those obtained via Sonogashira–Hagihara coupling. The heterogeneous nature of the photoinitiators makes them easily separable from the media and more importantly reusable for further polymerizations while retaining the photocatalytic activity.

Microporous organic polymer networks with weakly coordinating cations in their backbone have been synthesised by metal catalysed C–C bond forming reactions. A functionalised tetraphenylphosphonium ion was synthesised and successfully used as a tecton in a co-polymerisation with tetrakis(4-bromophenyl) methane using nickel catalysed Yamamoto coupling and with triethynylbenzene in a palladium catalysed Songashira–Hagihara reaction. The microporous materials showed an apparent BET surface area of 1455 m2 g−1 and 540 m2 g−1, respectively. The Yamamoto product provide a CO2 uptake of 2.49 mmol g−1 at 273 K and 1 bar. After ion exchange with chloride CO2 uptake is further increased to 2.85 mmol g−1.

An alkaline form of ‘dry water’—a ‘dry base’—is prepared by the high-speed mixing of aqueous solutions of metal carbonates or organic amines with hydrophobic silica nanoparticles. Despite being mostly water, the dry base looks and flows like a powder, and adsorbs CO2 rapidly without any mixing because of its high surface-to-volume ratio. Unlike normal aqueous base solutions, dry bases can be non-corrosive because they do not readily wet surfaces.

Combinatorial Geometry (CG) is one formulation for computational geometric models that is commonly used in many neutron transport simulation codes. The use of CG is advantageous since it permits an accurate yet concise representation of complex reactor models with a nominal memory footprint. OpenCG is a software package for combinatorial geometry models being developed at the Massachusetts Institute of Technology. The goal for OpenCG is to provide an easy-to-use, physics agnostic library to build geometry models of nuclear reactor cores. OpenCG is a free, open source library with an easy-to-use Python interface to provide nuclear engineers a single, powerful framework for modeling complex reactor geometries. Compatibility modules for commonly used nuclear reactor physics codes, such as OpenMC, OpenMOC, and Serpent, are being concurrently developed for rapid and easy exportation of an OpenCG model directly into the relevant input file format for each code of interest. The present work describes OpenCG and describes some of the novel and useful algorithms included with the software package., National Science Foundation (U.S.). Graduate Research Fellowship Program (Grant 112237), United States. Department of Energy (Center for Exascale Simulation of Advanced Reactors (CESAR). Contract DE-AC02-06CH11357))

We review the design and use of microporous polymers for pre- and post-combustion capture of CO2. Microporous organic polymers are promising candidates for CO2 capture materials. They have good physicochemical stabilities and high surface areas. Ultrahigh-surface-area microporous organic polymers could find use in pre-combustion capture, while networks with lower surface areas but higher heats of sorption for CO2 might be more relevant for lower pressure, post-combustion capture. We discuss strategies for enhancing CO2 uptakes including increasing surface area, chemical functionalization to provide high-enthalpy binding sites and the potential for pore size tuning. © 2013 Society of Chemical Industry