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This chapter explores arcade videogames as interfaces for performance in the context of digital art. When a new medium is invented it inevitably undergoes experimentation, and the hardware and soft...

This study aims at improving the knowledge on the effects of gas injection, bubbles sizes and contaminants on oxygen transfer in microbubble clouds. First the effects of gas injection on oxygen transfer are studied and linked to several parameters that change together with changes in flow rate, namely bubble sizes and rise velocities. Oxygen transfer is then studied in the presence of contaminants that are shown to affect bubble size distribution, modify bubble dynamics and interfacial mass transfer. Oxygen transfer efficiencies are also measured in wastewater and compared with those obtained in aqueous solutions. The agreement between contaminated water in the lab (Triton X100) and wastewater experiments is emphasised as this offers the possibility to develop fundamental understanding relevant to wastewater under laboratory conditions. The role of the surfactants on the volumetric oxygen transfer coefficient is further analysed in terms of specific interfacial area and transfer coefficients, respectively. Interestingly, this shows that the increase in oxygen transfer efficiency as the concentration in Pentanol increases is due to the increase in interfacial area while the transfer coefficients decrease.

The remarkable adsorption capacity of graphene derived materials has prompted their examination in composite materials suitable for deployment in treatment of contaminated waters. In this study, crosslinked calcium alginate – graphene oxide beads were prepared and activated by exposure to pH 4 by using 0.1M HCl. The activated beads were investigated as novel adsorbents for the removal of organic pollutants (Methylene Blue dye and the pharmaceuticals Famotidine and Diclofenac) with a range of physicochemical properties. Effects of initial pollutant concentration, temperature, pH and adsorbent dose were investigated and kinetic models were examined for fit to the data. Maximum adsorption capacities qmax obtained were 1334, 35.50 and 36.35 mg g-1 for the uptake of Methylene blue, Famotidine and Diclofenac respectively. The equilibrium adsorption had an alignment with Langmuir isotherms while the kinetics were most accurately modelled using a pseudo- first –order and second order models according to the regression analysis. Thermodynamic parameters such as ΔG◦, ΔH◦ and ΔS◦ were calculated and the adsorption process was determined to be exothermic and spontaneous.

Hydrophobic membrane contactors represent a promising solution to the problem of recycling ammoniacal nitrogen (N-NH4) molecules from waste, water or wastewater resources. The process has been shown to work best with wastewater streams that present high N-NH4 concentrations, low buffering capacities and low total suspended solids. The removal of N-NH4 from rendering condensate, produced during heat treatment of waste animal tissue, was assessed in this research using a hydrophobic membrane contactor. This study investigates how the molecular composition of rendering condensate wastewater undergo changes in its chemistry in order to achieve suitability to be treated using hydrophobic membranes and form a suitable product. The main objective was to test the ammonia stripping technology using two types of hydrophobic membrane materials, polypropylene (PP) and polytetrafluoroethylene (PTFE) at pilot scale and carry out: (i) Process modification for NH3 molecule removal and (ii) product characterization from the process. The results demonstrate that PP membranes are not compatible with the condensate waste as it caused wetting. The PTFE membranes showed potential and had a longer lifetime than the PP membranes and removed up to 64% of NH3 molecules from the condensate waste. The product formed contained a 30% concentrated ammonium sulphate salt which has a potential application as a fertilizer. This is the first demonstration of hydrophobic membrane contactors for treatment of condensate wastewater.

In this work, antifouling hybrid ultrafiltration membranes were manufactured using polysulfone (PSf) and sulfonic acid functionalized TiO 2 nanotubes (TNTs-SO 3 H). TNTs-SO 3 H were first synthesized by performing a coupling reaction between 3-mercaptopropyl trimethoxysilane and hydroxyl groups on TiO 2 nanotubes with in situ oxidation using 30 wt% H 2 O 2 solution. Hybrid membranes containing TNTs-SO 3 H up to 5 wt% were then prepared from the blend solutions of PSf/TNTs-SO 3 H via a non-solvent induced phase separation (NIPS) method. The hybrid membranes were characterized using contact angle, Fourier transform infrared spectroscopy, scanning electron microscopy and surface zeta potential studies. The antifouling capability of hybrid membranes with bovine serum albumin and humic acid (HA) as model foulants were investigated in detail. Hybrid membranes exhibited better water permeability and antifouling performance during filtration of foulant solutions. The ultrafiltration of HA solutions of different concentrations was carried out at pH = 7 and 1 bar feed pressure, with the removal of HA from aqueous solution being controlled through the charged behaviour, porosity and exclusion of HA by hybrid membranes. The maximum removal of HA from 20 ppm aqueous solution was achieved using the hybrid membrane MTS-5 containing 5 wt% TNTs-SO 3 H.

In this work, graphene oxide (GO)−TiO2 nanocomposite was synthesized by in situ sol−gel reaction at pH=2 using GO nanosheets suspension and titanium isopropoxide precursor. The synthesized GO−TiO2 nanocomposite was explored as a filler to fabricate improved antifouling novel hybrid ultrafiltration membranes for removal of humic acid from aqueous solution. Membranes were fabricated from polymer blend solutions containing polysulfone and GO−TiO2 with varied loading amount (0–5 wt%) by the non-solvent induced phase separation (NIPS) method. Contact angle, atomic force microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and outer surface zeta potential studies were conducted in order to characterise the membranes in terms of roughness, structure, surface properties and charge. The porous hydrophilic hybrid membranes were shown to have an asymmetric structure with improved surface roughness. The water permeability and antifouling capacity of hybrid membranes with 10 ppm HA solution were dependent on the loading amount of GO–TiO2. Incorporation of GO–TiO2 nanocomposite was found to improve the antifouling characteristics of the membranes when challenged with HA solutions. Irreversible HA fouling was substantially reduced with increased loading of GO−TiO2 nanocomposite (wt%). The lowest irreversible fouling ratio (3.2%) was obtained for the membrane containing 5 wt% nanocomposite (to total wt% of PSf, MG−5). Ultrafiltration of HA solutions of varied concentrations using hybrid membranes was studied at pH=7 and 1 bar feed pressure. The removal efficiency of hybrid membranes for HA was controlled by the membrane surface charge concentration, porosity and HA exclusion. The membrane MG−5 had the highest HA removal efficiency for 10 ppm HA solution at pH=7.

The perceived attraction of nanotubular TiO2 in diverse applications has brought the researchers attention to focus on various aspects of nanotube synthesis and modification. In this work, the visible light activity of dye sensitized TiO2 nanotubes obtained in powder form via rapid breakdown anodization was investigated. Tetra (4-carboxy phenyl) porphyrin (TCPP) was used as a visible light sensitizing component on phase pure anatase TiO2 nanotubes (ATiNT). The effect of introducing two different anchoring groups between the dye and TiO2 nanotubes on photocatalytic activity was investigated. The visible light photocatalytic efficiency of the prepared ATiNT/TCPP composites was tested on a pharmaceutical compound, famotidine (FAM) in order to avoid degradation through photosensitization. For the given amount of TCPP load on ATiNT, the presence of a lengthy anchoring group between TCPP and ATiNT had a negative influence on the photocatalytic activity. Direct oxidation through visible-light-generated holes in the ATiNT/TCPP composite appeared to be the most significant pathway for FAM photocatalysis.

Members of the voltage-gated K+ channel subfamily (Kv1), involved in regulating transmission between neurons or to muscles, are associated with human diseases and, thus, putative targets for neurotherapeutics. This applies especially to those containing Kv1.1 α subunits which become prevalent in murine demyelinated axons and appear abnormally at inter-nodes, underlying the perturbed propagation of nerve signals. To overcome this dysfunction, akin to the consequential debilitation in multiple sclerosis (MS), small inhibitors were sought that are selective for the culpable hyper-polarising K+ currents. Herein, we report a new semi-podand – compound 3 – that was designed based on the modelling of its interactions with the extracellular pore region in a deduced Kv1.1 channel structure. After synthesis, purification, and structural characterisation, compound 3 was found to potently (IC50 = 8 µM) and selectively block Kv1.1 and 1.6 channels. The tested compound showed no apparent effect on native Nav and Cav channels expressed in F-11 cells. Compound 3 also extensively and selectively inhibited MS-related Kv1.1 homomer but not the brain native Kv1.1- or 1.6-containing channels. These collective findings highlight the therapeutic potential of compound 3 to block currents mediated by Kv1.1 channels enriched in demyelinated central neurons.

K+ channels containing Kv1.1 α subunits, which become prevalent at internodes in demyelinated axons, may underlie their dysfunctional conduction akin to muscle weakness in multiple sclerosis. Small inhibitors were sought with selectivity for the culpable hyper-polarizing K+ currents. Modeling of interactions with the extracellular pore in a Kv1.1-deduced structure identified diaryldi(2-pyrrolyl)methane as a suitable scaffold with optimized alkyl ammonium side chains. The resultant synthesized candidate [2,2'-((5,5'(di-p-topyldiaryldi(2-pyrrolyl)methane)bis(2,2'carbonyl)bis(azanediyl)) diethaneamine·2HCl] (8) selectively blocked Kv1.1 channels (IC50 ≈ 15 μM) recombinantly expressed in mammalian cells, induced a positive shift in the voltage dependency of K+ current activation, and slowed its kinetics. It preferentially inhibited channels containing two or more Kv1.1 subunits regardless of their positioning in concatenated tetramers. In slices of corpus callosum from mice subjected to a demyelination protocol, this novel inhibitor improved neuronal conduction, highlighting its potential for alleviating symptoms in multiple sclerosis.

Nanostructured titania supported on activated carbon (AC), termed as integrated photocatalytic adsorbents (IPCAs), were prepared by ultrasonication and investigated for the photocatalytic degradation of acetaminophen (AMP), a common analgesic and antipyretic drug. The IPCAs showed high affinity towards AMP (in dark adsorption studies), with the amount adsorbed proportional to the TiO2 content; the highest adsorption was at 10 wt% TiO2. Equilibrium isotherm studies showed that the adsorption followed the Langmuir model, indicating the dependence of the reaction on an initial adsorption step, with maximum adsorption capacity of 28.4 mg/g for 10 % TiO2 IPCA. The effects of initial pH, catalyst amount and initial AMP concentration on the photocatalytic degradation rates were studied. Generally, the AMP photodegradation activity of the IPCAs was better than that of bare TiO2. Kinetic studies on the photocatalytic degradation of AMP under UV suggest that the degradation followed Langmuir-Hinshelwood (L-H) kinetics, with an adsorption rate constant (K) that was considerably higher than the photocatalytic rate constant (k r), indicating that the photocatalysis of AMP is the rate-determining step during the adsorption/photocatalysis process.

Numerous approaches have been suggested for differentiating point and diffuse sources of nitrate contamination, including nitrate stable isotopes, microbiological analyses, genetic markers and chemical markers. Each approach has its own strengths and limitations. As a result, the most appropriate approach to use largely depends upon the scenario and the context of the study. However, available data on nitrate source determination is highly fragmented and approach dependent, with very little if any interface between the different techniques. This makes it difficult for stakeholders to identify the most suitable approach to adopt in a specific scenario. Therefore, this paper examines the development and application of a decision-support tool to support environmental forensics studies for nitrate contamination. In particular, this tool can support policy makers, regulators and operators within the field in understanding the environmental hazards and processes resulting from nitrate contamination, and to implement appropriate actions for limiting the impacts that may arise from such contamination. The tool was developed using the IDEF0 modeling system, and evaluated by interviewing key stakeholders who suggested a number of important implications for practice.

Humans have represented data in many forms for thousands of years, yet the main sensory channel we use to perceive these representations today still remains largely exclusive to sight. Recent developments, such as advances in digital fabrication, microcontrollers, actuated tangibles, and shape-changing interfaces offer new opportunities to encode data in physical forms and have stimulated the emergence of 'Data Physicalization' as a research area. The aim of this workshop is (1) to create an awareness of the potential of Data Physicalization by providing an overview of state-of-the-art research, practice, and tools and (2) to build a community around this emerging field and start to discuss a shared research agenda. This workshop therefore addresses both experienced researchers and practitioners as well as those who are new to the field but interested in applying Data Physicalization to their own (research) practice. The workshop will provide opportunities for participants to explore Data Physicalization hands-on, by creating their own prototypes. These practical explorations will lead into reflective discussions on the role tangibles and embodiment play in Data Physicalization and the future research challenges for this area.

A novel, multimicrocapillary flow reactor (MμCFR) was constructed and applied to a series of sensitized photoadditions involving 2(5H)-furanones. The reactor allowed for rapid and energy-, time-, and space-efficient sensitizer screening, process optimization, validation, scale-up, and library synthesis.

Photooxygenation of 1,5-dihydroxynaphthalene to Juglone was studied in a falling film microreactor. Moderate conversion rates of up to 31% were achieved after just 160 s of exposure to visible light. In contrast, batch reactions gave much lower conversions of up to 14% after a prolonged time period of 10 min. The difference in performance is explained by the superior light penetration in the microfilm and the large gas-liquid contact area.

Two separate methods were used to prepare a tetra(4-carboxyphenyl)porphyrin (TCPP)-TiO2 composite. In method A TCPP was absorbed onto TiO2 in methanol at room temperature, whilst in method B TCPP was absorbed onto TiO2 in dimethylformamide (DMF) at reflux. Both composites exhibited the same physical and chemical characteristics as shown by FT-IR, SEM and UV–vis diffuse reflectance spectroscopy (DRS). The photocatalytic activity of both composites was then determined by HPLC monitoring of the photo-degradation of the pharmaceutical Famotidine under both visible and solar light irradiation. The recyclability of the composites was also examined by recovery of the composite post-reaction, although the absorbed TCPP was found to partially degrade, the recycled composite still exhibited catalytic behaviour. All reactions were monitored by HPLC which revealed that the photodegradation of Famotidine by the TCPP–TiO2 composites does not lead to complete mineralisation, but instead generates a range of intermediates/products. Investigation of these products by LC–MS–MS and DI–MS analysis found that one major degradation product was formed, the S-oxide of Famotidine. The TCPP–TiO2 composites were also screened in the photo-degradation of the pharmaceuticals tamsulosin and solifenacin using the optimised conditions developed for famotidine. However, the composites were found to be ineffective for the photo-catalytic degradation of these compounds, demonstrating that this class of composite are only effective for specific compounds.

A SPE-LC-MS/MS method was developed and validated for the determination of three active pharmaceutical ingredients [API A (3-([2-(diaminomethyleneamino)thiazol-4-yl]methylthio)-N′-sulfamoyl propanimid amide, API B 5-[(2 R)-2-[2-(2-ethoxyphenoxy)ethylamino]propyl]-2-methoxybenzenesulfonamide hydrochloride, API C 1-azabicyclo[2.2.2]octan-8-yl (1S)-1-phenyl-3,4-dihydro-1H-isoquinoline-2-carboxylate] in the wastewater of a chemical synthesis production facility. The SPE-LC-MS/MS method was validated in actual influent and effluent samples. Linearity, LOD, LOQ, repeatability, intermediate precision, and recovery were determined. An LOQ of 400 μg · L−1, 1.0 μg · L−1, and 6 μg · L−1, repeatability of 2.5% CV, 14.8% CV, and 11.9% CV, intermediate precision of 7.8% CV, 11.0% CV, and 8.7% CV and SPE recovery of 114%, 103%, and 91% was determined for API A, B, and C, respectively, in influent. An LOQ of 400 μg · L−1, 0.8 μg · L−1, and 6 μg · L−1, repeatability of 2.0% CV, 11.0% CV, and 10.9% CV, intermediate precisi...

A series of 4,4'-dimethoxybenzophenone mediated intra- and intermolecular photodecarboxylation reactions involving phthalimides have been examined under microflow conditions. Conversion rates, isolated yields and chemoselectivities were compared to analogous reactions in a batch photoreactor. In all cases investigated, the microreactions gave superior results thus proving the superiority of microphotochemistry over conventional technologies.

In recent years, concerns about the occurrence and fate of active pharmaceutical ingredients, solvents, intermediates and raw materials that could be present in water and wastewater including pharmaceutical industry wastewater has gained increasing attention. Traditional wastewater treatment methods, such as activated sludge, are not sufficient for the complete removal of active pharmaceutical ingredients and other wastewater constituents from these waters. As a result, complementary treatment methods such as membrane filtration, reverse osmosis and activated carbon are often used in conjunction with the traditional methods for treatment of industrial wastewater. Most of the literature published to date has been on the treatment of municipal wastewater. However, there is a growing body of research that looks at the presence of active pharmaceutical ingredients in industrial wastewater, the treatment of these wastewaters and the removal rates. This article, reviews these treatment methods and includes both traditional methods and advanced oxidation processes. The paper concludes by showing that the problem of pharmaceuticals in wastewaters cannot be solved merely by adopting end of pipe measures. At source measures, such as replacement of critical chemicals, reduction in raw material consumption should continue to be pursued as the top priority.

Integrated photocatalytic adsorbents (IPCAs) based on TiO2-activated carbon synthesized by an ultrasonic impregnation technique have been used for the photodegradation of indomethacin (IND) in aqueous solutions. The IPCAs in dark adsorption studies had high affinity toward IND with the amount adsorbed proportional to the TiO2 loading. The adsorption capacity increased from 0.597 to 0.657 mmol/g with increase in TiO2 content from 0.5 to 10% in IPCAs. Three adsorption models, Langmuir, Freundlich and Sips, were used to describe the adsorption isotherms while the adsorption kinetic data were fitted to pseudofirst order and pseudosecond order models. The adsorption isotherm study showed that the adsorption followed both Sips and Langmuir models with high regression coefficients (R2) and low standard error (SE) and sum of residual square error (SSE) values. The adsorption kinetic data are well represented by pseudosecond order model. The kinetics of photocatalytic degradation under UV were found to follow a La...

Integrated photocatalytic adsorbents (IPCAs) comprised of nanocrystalline titanium dioxide (TiO2) and activated carbon (AC) were prepared using an ultrasonic impregnation technique. The IPCAs were characterised by scanning electron microscopy (SEM) and Fourier-transform infrared (FT-IR) spectroscopy and were employed as catalysts for the photodegradation of famotidine-an active pharmaceutical ingredient-in aqueous solutions using illumination from a 125 W medium pressure mercury lamp. The degradation kinetics were found to follow a pseudo-first-order rate law and varying TiO2 loadings induced different increases in the apparent first-order rate constant of the process. The kinetic behaviour can be described in terms of a modified Langmuir–Hinshelwood (LH) model. The IPCA prepared using a 10% TiO2 to AC loading exhibited the highest rate constant with a K C and k r of 0.0172 L/mg and 0.237 mg/L/min, respectively. The LH model fits the experimental data and elucidates the effect of the TiO2 content of the IPCA on the degradation rate. The use of calcination (heat treatment) in IPCA preparation and its effect on photocatalytic and adsorption performance were also investigated. The present work demonstrates that the combination of TiO2 and AC results in a promising material for application in the degradation of organic pollutants. The values of the adsorption equilibrium constants, K C , and the rate constants, k r , for the photodegradation of famotidine were dependent on TiO2 content of IPCAs.

Irradiations of alkyl phenylglyoxylates with sulfur-containing carboxylates yielded the corresponding photodecarboxylative addition products in moderate to good yields of 26-58%. Reductive photodimerization competed with decarboxylative addition in all cases. The reaction protocol was successfully transferred to a microreactor. With potassium 2-(methylsulfanyl)propionate, photoadditions gave diastereomeric mixtures with low selectivity for the like-isomer.

This article presents a new model that elucidates the etiology and adult manifestation of obsessive-compulsive disorder (OCD). The author links transactional analytic and psychoanalytic concepts of...

We report both the preparation and sensor evaluation of a new metal-free calixarene bridged binuclear phthalocyanine.

We report the synthesis, catalytic, and biological properties of new bridged and cyclic ferrocenyl azolium compounds.

We report a new direct route for the selective preparation of novel partial cone O-aryl ether calix[4]arenes to be used as new platforms for the preparation of non-aggregated dyes. These partial cone conformers have the aromatic substituents lying within the calix[4]arene annulus via the upper rim.

The current work is amongst the first to examine the potential usefulness of the nitrile functional group in potentiometric analytical sensors for soft metals. Nitrile functionality has hereby been incorporated into a calix[4]arene skeleton to give a series of new cation selective hosts. The analytical sensing behaviour of these hosts was examined by Ion Selective Electrode (ISE) based potentiometry. In all cases a preference for soft metals was observed, explained primarily in terms of soft–soft compatibility between calix[4]arene nitrile hosts and metal guests in combination with a classical ‘lock and key’ best fit mechanism. Hosts 2, 3 and 4 showed very strong responses towards Hg(II) ions, with Ag(I) being the main interferant. The introduction of electron delocalising aromaticity proximal to the nitrile functionality was thought to reduce the availability of negative charge for cation coordination, apparently affecting the Hg(II) cation in particular. An acute fall in Hg(II) response coupled with the emergence of Ag(I) as the primary ion was observed for 7 and 8.

Selective inhibitors of voltage-activated K(+) channels are needed for the treatment of multiple sclerosis. In this work it was discovered that porphyrins bearing 2-4 carbon alkyl ammonium side chains predominantly blocked the Kv1.1 current whilst Kv1.2 was susceptible to a porphyrin bearing polyamine side chains.

Molecularly imprinted polymers (MIPs) for 2,4-dichlorophenoxyacetic acid were synthesized via a noncovalent approach with 4-vinylpyridine as functional monomer and ethylene glycol dimethacrylate as cross-linker in a methanol/water mixture. Templated polymers synthesized in this self-assembly approach rely on complex formation between the target analyte and functional monomers in porogenic solution prior to radical polymerization. Consequently, the achievable selectivity is governed by the nature and stability of these complexes. The nature of noncovalent interactions responsible for complex formation during imprinting of the template 2,4-dichlorophenoxyacetic acid (2,4-D) with the functional monomer 4-vinylpyridine has been investigated. Fourier transform infrared and 1H NMR spectroscopies provide the fundamental analytical basis for rationalizing the mechanisms of recognition during the imprinting process probing the governing interactions for selective binding site formation at a molecular level. Molecular modeling studies in explicit solvent (chloroform and water) corroborate the importance of hydrogen bonding in aprotic solvents and of hydrophobic interactions in protic media in agreement with the experimental spectroscopic investigations of prepolymerization solutions. Furthermore, chromatographic studies of the synthesized MIPs provided insight on the importance of size, shape, and functionality during selective 2,4-D rebinding processes confirming the results obtained during the prepolymerization studies.

Among the variety of biomimetic recognition schemes utilizing supramolecular approaches molecularly imprinted polymers (MIPs) have proven their potential as synthetic receptors in numerous applications ranging from liquid chromatography to assays and sensor technology. Their inherent advantages compared to biochemical/biological recognition systems include robustness, storage endurance and lower costs. However, until recently only few contributions throughout the relevant literature describe quantitative analytical applications of MIPs for practically relevant analyte molecules and real-world samples. Increased motivation to thoroughly evaluate the true potential of MIP technology is clearly attributed to the demands of modern analytical chemistry, which include enhanced sensitivity, selectivity and applicability of molecular recognition building blocks at decreasing costs. In particular, the areas of environmental monitoring, food and beverage analysis and industrial process surveillance require analytical tools capable of discriminating chemicals with high molecular specificity considering increasing numbers of complex environmental contaminants, pollution of raw products and rigorous quality control requested by legislation and consumer protection. Furthermore, efficient product improvement and development of new products requires precise qualitative and quantitative analytical methods. Finally, environmental, food and process safety control issues favor the application of on-line in situ analytical methods with high molecular selectivity. While biorecognition schemes frequently suffer from degrading bioactivity and long-term stability when applied in real-world sample environments, MIPs serving as synthetic antibodies have successfully been applied as stationary phase separation matrix (e.g. HPLC and SPE), recognition component in bioassays (e.g. ELISA) or biomimetic recognition layer in chemical sensor systems. Examples such as MIP-based selective analysis of flavones/flavonoids in wine, the determination of mycotoxins in beverages and analysis of organic contaminants in environment samples will elucidate the perspectives of this technology and will be contrasted with the challenges of rational MIP design providing control on binding site density, receptor capacity and selectivity.

A third and new extracellular xylanase (XynC) was purified from birchwood xylan-induced culture filtrates of the mesophilic fungus Penicillium capsulatum . Purified XynC is an acidic protein (p I 2.8), with a relative molecular mass of 22±0.4 kDa and, unlike XynA and XynB from the same source, is not glycosylated. pH and temperature optima of 3.8 and 48 °C, respectively, were determined for XynC using standard assay conditions. Thermal stability was appreciable at pH 5.0, with an estimated half-life of 25 h at 50 °C and retention of full activity after 2 weeks at 30 °C. Substrate specificity studies revealed that XynC was exclusively xylanolytic. Complete inhibition of enzyme activity by N -bromosuccinimide, Hg 2+ , and carboxylate-specific reagents suggested the presence of essential tryptophan, cysteine and aspartate/glutamate residues. Kinetic parameters were assessed using a range of soluble and insoluble xylans. Apparent K m values ranged from 7.02 to 31.94 mg ml −1 , while V max values were highest for the more soluble substrates. High performance anion exchange chromatography (HPAEC) analysis of the products of hydrolysis confirmed that XynC is an endoxylanase (EC 3.2.1.8) and indicated that substrate solubility and degree of substitution modulate hydrolysis and product formation.

Partially substituted calix[4]arene ethyl ester derivatives were synthesized as important precursors for new series of non-symmetrical ion and molecule receptors by reacting p-t-butyl calix[4]arene and ethyl bromoacetate. Characteristics of PVC-membrane ion-selective electrodes based on the mono- and di-ester derivatives were compared to those of the well-known calix[4]arene tetraester cationophore. Sodium selectivity is only manifested with the tetraester derivative, whereas the diester complexes potassium and caesium, as well as sodium. Energy-minimized structures for the complexes show the ester groups are involved in sodium complexation for the tetraester and diester derivatives, whereas for the monester, the aryl macrocycle is more important. This provides an excellent example of the critical importance of preorganization on host-guest selectivity, which in turn defines the selectivity of chemical sensors based on such receptors. The influence of this selective ion-binding behavior on the characterization of these derivatives using mass spectroscopy is discussed.

A series of derivatisation reactions between p-t-butyl calix[4]arene and ethyl bromoacetate were carried out in order to prepare 1,3 diester substituted calix[4]arene. Mass spectral data, obtained from direct injection of samples, indicated that the reactions were rich in the desired product. Since the ultra violet (UV) spectra of the desired product and possible impurities are very similar, liquid chromatography (LC) chromatographic data seemed to corroborate these results. However, when on-line LC-UV-MS was carried out and each LC peak subjected to MS analysis as it eluted, a very different picture emerged. It was found that many of these reactions actually contained high levels of the monoester product which, having less affinity for sodium in the MS, is therefore seriously underestimated in any direct injection assay. LC-diode array detection (DAD) methods were also used to help successfully identify and characterise the compounds being formed in these complex reactions. The overall results obtained in this paper allowed the optimal reaction conditions to be determined for this reaction. LC-MS analysis of the chromatographic peaks also identified the presence of two isomers of the diester substituted calix[4]arene (1,3 and 1,2 diesters). The combination of LC and UV/MS detection is required for accurate analysis of the products of such reactions.

A novel continuous-flow photoreactor with parallel capillaries was constructed and successfully tested for the DMBP-sensitized addition of isopropanol to furanones. Complete conversions were achieved after a maximum of 10 min of irradiation with a single 350 nm lamp. The results were compared to analogous batch experiments using a conventional Rayonet chamber reactor equipped with 16 UVA lamps. The capillary tower generally showed higher space-time yields.

The synthesis of a propranolol amide derivative of p-allylcalix[4]arene is described, which has been designed to behave as a molecular sensor capable of distinguishing chiral amines on the basis of their shape and chirality. This molecule can discriminate between the enantiomers of phenylalaninol through the quenching of the fluorescence emission in methanol in contrast to an (S)-dinaphthylprolinol calix[4]arene derivative, which can discriminate between the enantiomers of phenylglycinol, but not phenylalaninol. The separation between the naphthyl fluorophores and the hydrogen-bonding sites within the chiral cavity can be tuned to recognize guest amines with similar separation between aryl groups and hydrogen-bonding sites. The formation of metal ion complexes of the p-allylcalix[4]arene propranolol amide derivative is shown to induce a more regular and rigid cone conformation in the calix[4]arene macrocycle, which generates a significant enhancement in the observed enantiomeric discrimination.

The DMBP-sensitized addition of isopropanol to furanones was studied in a novel LED-driven microchip reactor. Complete conversions were achieved after just 2.5 to 5 min of irradiation with 6 × 365 nm high-power LEDs. The results were compared to analogous experiments using a conventional batch reactor.

Ion-selective optode membranes incorporating calix[4]arene derivatives for cation recognition, and a lipophilic acidochromic dye for transduction have been prepared. The response of the resulting optode membranes has been measured over the range 400–800 nm. Comparisons are made between the analytical performance of a commercially available pH indicator (ETH 5294) and an alternative dye 9-(4-diethylamino-2-octadecanoatestyryl)-acridine with respect to dynamic range, selectivity and stability/lifetime. K exch values and other membrane parameters have been estimated by means of fitting experimental data to theoretically derived equations.