Hydrogel photocatalysts for efficient energy conversion and environmental treatment

Photocatalysts have attracted great research interest owing to their excellent properties and potential for simultaneously addressing challenges related to energy needs and environmental pollution. Photocatalytic particles need to be in contact with their respective media to exhibit efficient photocatalytic performances. However, it is difficult to separate nanometer-sized photocatalytic materials from reaction media later, which may lead to secondary pollution and a poor recycling performance. Hydrogel photocatalysts with a three-dimensional (3D) network structures are promising support materials for photocatalysts based on features such as high specific surface areas and adsorption capacities and good environmental compatibility. In this review, hydrogel photocatalysts are classified into two different categories depending on their elemental composition and recent progresses in the methods for preparing hydrogel photocatalysts are summarized. Moreover, current applications of hydrogel photocatalysts in energy conversion and environmental remediation are reviewed. Furthermore, a comprehensive outlook and highlight future challenges in the development of hydrogel photocatalysts are presented.     

Caspase 1-independent IL-1beta release and inflammation induced by the apoptosis inducer Fas ligand

Anchietia salutaris tea is traditionally used in Brazil to treat allergies, suggesting it contains compounds with antagonistic activity on the allergic mediators. We have evaluated extracts and semi-purified fractions of Anchietia salutaris as a source of compounds having this type of antagonism on the contraction induced in guinea-pig lung parenchymal strips and on platelet aggregation and shape change. After 10 min pre-incubation dichloromethane extracts containing 30 or 100 microg mL(-1) inhibited the contraction induced by prostaglandin D2 (PGD2) in guinea-pig lung parenchymal strips with dose ratios (DR) of 0.76+/-0.14 and 0.93+/-0.19, respectively; the amount of inhibition depended both on the concentration and on the time of pre-incubation (DR after 30 min pre-incubation was 1.21+/-0.51). The dichloromethane extract and its semi-purified fractions also inhibited the contractions induced by U46619, a more potent, stable, synthetic agonist of thromboxane A2 (TxA2) prostanoid (TP) receptors, the receptors acted upon by PGD2 to produce lung contractions. The dichloromethane extract did not inhibit the lung parenchymal contractions induced by histamine, leukotriene D4 (LTD4) or platelet-activating factor (PAF). Platelet aggregation induced by U46619, adenosine 5'-diphosphate (ADP) or PAF was not inhibited by the dichloromethane extract. Indeed, the extract potentiated platelet aggregation induced by low concentrations of these agonists and also potentiated the shape change induced by U46619. These results imply that the dichloromethane extract of Anchietia salutaris and its semi-purified fractions contain an active principle that competitively inhibits TxA2 TP receptors, the stimulation of which causes lung parenchymal contraction. The inhibition seems to be selective for this receptor subtype, because the extract fails to inhibit platelet aggregation or shape change. This provides additional support of earlier reports suggesting the occurrence of TP receptor subtypes.     

Design of FIR linear phase filters with discrete coefficients usingHopfield neural networks

A novel method is presented for designing FIR linear phase filters with discrete coefficients using Hopfield neural networks. The proposed procedure is based on the minimisation of the energy function of the Hopfield neural network, and can produce a good solution to the design of FIR linear phase filters with discrete coefficients     

Murine coronavirus-induced subacute fatal peritonitis in C57BL/6 mice deficient in gamma interferon

Gamma interferon-deficient (IFN-gamma-/-) mice with a C57BL/6 background were infected intraperitoneally with mouse hepatitis virus strain JHM (JHMV). In contrast to IFN-gamma-+/- and IFN-gamma+/+ mice, JHMV persisted in IFN-gamma-/- mice and induced death during the subacute phase of the infection. Unexpectedly, infected IFN-gamma-/- mice showed severe peritonitis accompanying the accumulation of a viscous fluid in the abdominal and thoracic cavities in the subacute phase. Destructive changes of hepatocytes were not observed. Administration of recombinant IFN-gamma protracted the survival time of IFN-gamma-/- mice after JHMV infection. These results demonstrate that IFN-gamma plays a critical role in viral clearance in JHMV infection. They also show that a resultant persistent JHMV infection induces another form of disease in IFN-gamma-/- mice, which bears a resemblance to feline infectious peritonitis in cats.     

Effect of the addition of NH4F on anodic behaviors of DSA-type electrodes in H2SO4-(NH4)2SO4 solutions

The effect of NH₄F addition on the high-anodic behaviors of various DSA-type electrodes was investigated in a mixture of sulfuric acid and ammonium sulfate. The pronounced effect of NH₄ addition was observed on DSA-type Ti/RuO₂, Ti/IrO₂?TiO₂ electrodes, but not observed on the other electrodes studied. The close relationship was found between the increment of the electrode potential caused by the NH₄ addition and the quantity of F^? adsorbed on the electrode surface. The effect of NH₄F addition was considered to be resulted from the adsorption of F^? on the electrode surface, and the presence of adsorbed F^? was directly proved.     

Size exclusion behavior of polymers in amide solvents

Summary The size exclusion chromatography of neutral polymers and polymers containing ionic groups was investigated using N,N-dimethylacetamide (DMA) as mobile phase. As reported previously for N,N-dimethylformamide (DMF), acrylonitrile polymers containing charges, even those at terminal end groups, showed markedly small retention volumes and multimodal peaks by refractive index and 280 nm UV detectors. In DMA containing small amounts of LiBr the peaks of the ionic polymers were shifted to small retention volumes while neutral polymers with analogous chemical structures did not show the same behavior. As in the case of DMF the peculiarities observed in DMA were attributed to the formation of supramolecular structures by the interaction of the ionic groups in the polymer and the ionic species from DMA decomposition.     

The electrocatalytic activities of the Pd-doped MnO2 for the chlorine evolution reaction

The anodic evolution of chlorine on the massive β-MnO₂ doped with various amounts of Pd was investigated in acidic chloride solution. A second-order relation was found between the rate of the chlorine evolution reaction and the number of active Pd sites at the electrode surface. And it was confirmed that, in the relatively low doped electrodes, the active sites are more effectively dispersed on the surface with microscopic homogeneity. From the activation energies, it was also suggested that the reaction mechanism on the MnO₂ doped with relatively small amounts of Pd is somewhat different from that on the pure PdO electrode.     

Molecular species of 1-O-alk-1′-enyl-2-acyl-, 1-O-alkyl-2-acyl- and 1,2-diacyl glycerophospholipids in Japanese oysterCrassostrea gigas (Thunberg)

Molecular species of 1-O-alk-1′-enyl-2-acyl-, 1-O-alkyl-2-acyl-, and 1,2-diacyl-sn-glycero-3-phosphoethanolamine (EPL) andsn-glycero-3-phosphocholine (CPL) of Japanese oysterCrassostrea gigas were analyzed by selectedion monitoring gas chromatography/mass spectrometry using electron impact ionization. The characteristic fragment ions, [RCH=CH+56]⁺ due to the alkenyl residue in thesn-1 position and [RCO+74]⁺ due to the acyl residue in thesn-2 position of alkenylacylglycerols, [R+130]⁺ due to the alkyl residue in thesn-1 position and [RCO+74]⁺ due to the acyl residue in thesn-2 position of alkylacylglycerols, [RCO+74]⁺ due to the acyl residues in thesn-1 and/orsn-2 positions of diacylglycerols, and [M−57]⁺ being indicative of the corresponding molecular weight, were used for structural assignments. For alkenylacyl EPL and CPL, 19 and 16 molecular species were determined, respectively. Two molecular species, 18∶0alkenyl-22∶6n−3 and 18∶0-alkenyl-22∶2-non-methylene interrupted diene (NMID), amounted to 53.2% and 47.9%, respectively. The alkylacyl EPL and CPL consisted of 16 and 20 molecular species, respectively, and the prominent components were 18∶0alkyl-22∶2NMID, 20∶1alkyl-20∶1n−11 (27.4%) and 20∶1alkyl-20∶2NMID (16.3%) in the former, and 16∶0alkyl-20∶5n−3 (23.0%) and 16∶0alkyl-22∶6n−3 (21.6%) in the latter. For the diacyl EPL and CPL, 14 and 51 molecular species were determined, respectively. The major molecular species were 18∶0–20∶5n−3 (37.4%), 16∶0–20∶5n−3 (14.2%) and 18∶1n−7–22∶2NMID (13.2%) in the former, and 16∶0–20∶5n−3 (33.4%) and 16∶0–22∶6n−3 (22.3%) in the latter. It was found that there were significant differences in the molecular species between the alkylacyl and diacyl EPL and the alkylacyl and diacyl CPL; the number of molecular species was larger in CPL than in EPL, while the number of total carbons and double bonds of the major molecular species were larger in the EPL than in the CPL. Alkenylacyl EPL were similar to alkenylacyl CPL in molecular species composition.     

Brave induction: a logical framework for learning from incomplete information

This paper introduces a novel logical framework for concept-learning called brave induction. Brave induction uses brave inference for induction and is useful for learning from incomplete information. Brave induction is weaker than explanatory induction which is normally used in inductive logic programming, and is stronger than learning from satisfiability, a general setting of concept-learning in clausal logic. We first investigate formal properties of brave induction, then develop an algorithm for computing hypotheses in full clausal theories. Next we extend the framework to induction in nonmonotonic logic programs. We analyze computational complexity of decision problems for induction on propositional theories. Further, we provide examples of problem solving by brave induction in systems biology, requirement engineering, and multiagent negotiation.     

Novel Method to Measure the Creep Strength of Adhesively Bonded Butt Joints Subjected to Constant Loading Using a Hydro-Pneumatic Testing Machine

This article proposes a new method to measure the creep strength of adhesively bonded joints using a hydro-pneumatic testing machine and a specimen holder, on which multi-specimens can be mounted in one testing machine. Creep tests were conducted on stainless steel butt joints bonded with epoxy adhesives. A hydro-pneumatic loading system was introduced to avoid successive failures of multi-specimens as well as to achieve a stable and constant loading through the experiments. Even after a failure occurs in one of the joints and thus generates an impact, the loading system is capable of absorbing the shock so that the other remaining joints do not fail simultaneously. It was experimentally verified that choke valves, which were introduced in the hydraulic circuit of the system, worked as a damper when failure occurred. Additionally, it was established that automatic reloading to the remaining specimens after the failure was short enough compared with the creep rupture time. As this new method relates to the efficiency of creep testing, the utility of the proposed approach with the multi-specimen setup has been verified.