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Porous liquids (PLs) are a new type of fluid sorbent investigated mainly for the separation of gas mixtures. Here, we explore their application to the separation of miscible liquids, using MEG/water (MEG=monoethylene glycol) and EtOH/water as proof‐of‐principle. Recovery of used MEG is industrially important but its extraction into conventional solvents from water is difficult. PLs ZIF‐8@PDMS (PL1, PDMS=polydimethylsilicone) or ZIF‐8@sesame oil (PL2) each consisting of 25 wt % of the hydrophobic microporous material ZIF‐8 dispersed in PDMS or sesame oil respectively, were formulated and found to be exceedingly physically stable to sedimentation. A 5 nm PEEK membrane was used to provide a permeable barrier between the PL and the alcohol/water phase. MEG was selectively extracted through the membrane from approximately 50 : 50 wt % MEG/water mixtures into the PL phase and this procedure could be applied repeatedly. It was effective for MEG/water mixtures as dilute as 3 : 97 wt %. The PL could also be regenerated (80 °C at 0.01 bar) and re‐used, suggesting its potential for continuous, cyclic extraction. Furthermore, PL3 (silicalite‐1@PDMS) was effective in selective alcohol extraction from beverages. It shows potential for lowering the alcohol concentration in gin or wine due to its excellent chemical stability and nontoxicity. Overall, we show that the enhanced adsorption properties of PLs due the presence of empty pores, which provides unusually high gas solubilities, also makes them, in principle, applicable to liquid‐liquid separations. [ABSTRACT FROM AUTHOR]

Mechanochemistry has developed rapidly in recent years for efficient chemicals and materials synthesis. Twin screw extrusion (TSE) is a particularly promising technique in this regard because of its continuous and scalable nature. A key aspect of TSE is that it provides high shear and mixing. Because of the high shear, it potentially also offers a way to delaminate 2‐D materials. Indeed, the synthesis of 2‐D materials in a scalable and continuous manor remains a challenge in their industrialization. Here, as a proof‐of‐principle, the automated, continuous mechanochemical exfoliation of graphite to give multi‐layer graphene (MLG, ≈6 layers) by TSE is demonstrated. To achieve this, a solid‐and‐liquid‐assisted extrusion (SLAE) process is developed in which organic additives such as pyrene are rendered liquid due to the high temperatures used, to assist with the exfoliation, and simultaneously solid sodium chloride is used as a grinding aid. This gave MLG in high yield (25 wt%) with a short residence time (8 min) and notably with negligible evidence for structural deterioration (defects or oxidation). [ABSTRACT FROM AUTHOR]

A continuous, scalable, and solvent‐free method for the synthesis of various naphthalic imides and perylene diimides (PDIs) using twin‐screw extrusion (TSE) is reported. Using TSE, naphthalic imides were obtained quantitatively without the need for excess amine reactant or product purification. With good functional‐group tolerance, alkyl and benzyl amine derived PDIs (incl. commercial dyes) were obtained in 50–99 % yield. Use of K2CO3, enabled synthesis of more difficult aniline‐derived PDIs. Furthermore, an automated continuous TSE process for Pigments Black 31 and 32 is demonstrated, with a throughput rate of about 1500 g day−1, corresponding to a space time yield of about 30×103 kg m−3 day−1, which is 1–2 orders of magnitude greater than for solvent‐based batch methods. These methods provide substantial waste reductions and improved efficiency compared to conventional solvent‐based methods. [ABSTRACT FROM AUTHOR]

Although mechanochemical synthesis is becoming more widely applied and even commercialised, greater basic understanding is needed if the field is to progress on less of a trial-and-error basis. We report that a mechanochemical reaction in a ball mill exhibits unusual sigmoidal feedback kinetics that differ dramatically from the simple first-order kinetics for the same reaction in solution. An induction period is followed by a rapid increase in reaction rate before the rate decreases again as the reaction goes to completion. The origin of these unusual kinetics is found to be a feedback cycle involving both chemical and mechanical factors. During the reaction the physical form of the reaction mixture changes from a powder to a cohesive rubber-like state, and this results in the observed reaction rate increase. The study reveals that non-obvious and dynamic rheological changes in the reaction mixture must be appreciated to understand how mechanochemical reactions progress. [ABSTRACT FROM AUTHOR]

Texture synthesis has grown into a mature field in computer graphics, allowing the synthesis of naturalistic textures and images from photographic exemplars. Surprisingly little work, however, has been dedicated to synthesizing tileable textures, that is, textures that when laid out in a regular grid of tiles form a homogeneous appearance suitable for use in memory-sensitive real-time graphics applications. One of the key challenges in doing so is that most natural input exemplars exhibit uneven spatial variations that, when tiled, show as repetitive patterns. We propose an approach to synthesize tileable textures while enforcing stationarity properties that effectively mask repetitions while maintaining the unique characteristics of the exemplar. We explore a number of alternative measures for texture stationarity and show how each measure can be integrated into a standard texture synthesis method (PatchMatch) to enforce stationarity at user-controlled scales. We demonstrate the efficacy of our approach using a database of 118 exemplar images, both from publicly available sources as well as new ones captured under uncontrolled conditions, and we quantitatively analyze alternative stationarity measures for their robustness across many test runs using different random seeds. In conclusion, we suggest a novel synthesis approach that employs local histogram matching to reliably turn input photographs of natural surfaces into tiles well suited for artifact-free tiling. [ABSTRACT FROM AUTHOR]

Evolutionary ecologists commonly use reaction norms, which show the range of phenotypes produced by a set of genotypes exposed to different environments, to quantify the degree of phenotypic variance and the magnitude of plasticity of morphometric and life-history traits. Significant differences among the values of the slopes of the reaction norms are interpreted as significant differences in phenotypic plasticity, whereas significant differences among phenotypic variances (variance or coefficient of variation) are interpreted as differences in the degree of developmental instability or canalization. We highlight some potential problems with this approach to quantifying phenotypic variance and suggest a novel and more informative way to plot reaction norms: namely 'a plot of log (variance) on the y-axis versus log (mean) on the x-axis, with a reference line added'. This approach gives an immediate impression of how the degree of phenotypic variance varies across an environmental gradient, taking into account the consequences of the scaling effect of the variance with the mean. The evolutionary implications of the variation in the degree of phenotypic variance, which we call a 'phenotypic variance gradient', are discussed together with its potential interactions with variation in the degree of phenotypic plasticity and canalization. [ABSTRACT FROM AUTHOR]

Agencies charged with nature conservation and protecting built-assets from fire face a policy dilemma because management that protects assets can have adverse impacts on biodiversity. Although conservation is often a policy goal, protecting built-assets usually takes precedence in fire management implementation. To make decisions that can better achieve both objectives, existing trade-offs must first be recognized, and then policies implemented to manage multiple objectives explicitly. We briefly review fire management actions that can conflict with biodiversity conservation. Through this review, we find that common management practices might not appreciably reduce the threat to built-assets but could have a large negative impact on biodiversity. We develop a framework based on decision theory that could be applied to minimize these conflicts. Critical to this approach is (1) the identification of the full range of management options and (2) obtaining data for evaluating the effectiveness of those options for achieving asset protection and conservation goals. This information can be used to compare explicitly the effectiveness of different management choices for conserving species and for protecting assets, given budget constraints. The challenge now is to gather data to quantify these trade-offs so that fire policy and practices can be better aligned with multiple objectives. [ABSTRACT FROM AUTHOR]

Aina VH Greig, Stuart E James, Angus D McGrouther, Giorgio Terenghi and Geoffrey Burnstock. Purinergic receptor expression in the regenerating epidermis in a rat model of normal and delayed wound healing. This study investigated changes in the protein expression of purinergic receptors in the regenerating rat epidermis during normal wound healing, in denervated wounds, and in denervated wounds treated with nerve growth factor (NGF), where wound healing rates are normalized. Excisional wounds were placed within denervated, pedicled, oblique, groin skin flaps, and in the contralateral abdomen to act as a control site. Six rats had NGF-treated wounds and six had untreated wounds. Tissue was harvested at day four after wounding. The re-epithelializing wound edges were analyzed immunohistochemically for P2X5, P2X7, P2Y1 and P2Y2 receptors, and immunostaining of keratinocytes was quantified using optical densitometry. In normal rat epidermis, P2Y1 and P2Y2 receptors were found in the basal layer where keratinocytes proliferate; P2X5 receptors were associated with proliferating and differentiating epidermal keratinocytes in basal and suprabasal layers; P2X7 receptors were associated with terminally differentiated keratinocytes in the stratum corneum. In the regenerating epidermis of denervated wounds, P2Y1 receptor protein expression was significantly increased in keratinocytes ( P < 0.001) but P2Y2 receptor protein expression was significantly decreased ( P < 0.001). Conversely, NGF treatment of denervated wounds, reduced expression of P2Y1 receptors ( P < 0.001) in keratinocytes but enhanced expression of the P2Y2 receptors ( P < 0.01) compared with untreated denervated wounds. In innervated wounds, NGF treatment enhanced P2X5 ( P < 0.001) and P2Y1 receptor protein ( P < 0.001) expression in keratinocytes. P2X7 receptors were absent in all experimental wound healing preparations. P2X5, P2X7, P2Y1 and P2Y2 receptor protein expression in the regenerating epidermis was altered both during wound healing and also by NGF treatment. Possible roles for purinergic signalling and its relation to NGF in wound healing are discussed. [ABSTRACT FROM AUTHOR]

Kein Lösungsmittel bedeutet kein Lösungsmittelabfall und keine Wiederaufbereitungskosten, weshalb derzeit ein großes Interesse an der Entwicklung von lösungsmittelfreien Methoden besteht. In einer neueren Studie wurden verschiedene Zeolithe durch das Vermahlen der trockenen Ausgangsstoffe und Erhitzen auf 180 °C synthetisiert. Die Methode könnte zu erheblichen Einsparungen in der Zeolithsynthese führen. [ABSTRACT FROM AUTHOR]

No added solvent means no waste solvent or recycling costs. Understandably the chemical industry is interested in developing approaches to increase the product to solvent ratio in synthesis. In recent work various zeolites were prepared by grinding the dry materials and then heating to 180 °C, and this method could lead to significant savings in zeolite synthesis. [ABSTRACT FROM AUTHOR]