Face-Fusion of Icosahedral Boron Hydride Increases Affinity to γ‐Cyclodextrin: closo,closo‐[B₂₁H₁₈]⁻ as an Anion with Very Low Free Energy of Dehydration

[Abstract] The supramolecular recognition of closo,closo‐[B₂₁H₁₈]⁻ by cyclodextrins (CDs) has been studied in aqueous solution by isothermal titration calorimetry and nuclear magnetic resonance spectroscopy. These solution studies follow up on previous mass‐spectrometric measurements and computations, which indicated the formation and stability of CD ⋅ B₂₁H₁₈⁻ complexes in the gas phase. The thermodynamic signature of solution‐phase binding is exceptional, the association constant for the γ‐CD complex with B₂₁H₁₈⁻ reaches 1.8×10⁶ M⁻¹, which is on the same order of magnitude as the so far highest observed value for the complex between γ‐CD and a metallacarborane. The nature of the intermolecular interaction is also examined by quantum‐mechanical computational protocols. These suggest that the desolvation penalty, which is particularly low for the B₂₁H₁₈⁻ anion, is the decisive factor for its high binding strength. The results further suggest that the elliptical macropolyhedral boron hydride is another example of a CD binder, whose extraordinary binding affinity is driven by the chaotropic effect, which describes the intrinsic affinity of large polarizable and weakly solvated chaotropic anions to hydrophobic cavities and surfaces in aqueous solution.K.I.A. and W.M.N. are grateful to the DFG for grant NA-686/8 within the priority program SPP 1807 “Control of London Dispersion Interactions in Molecular Chemistry”. J.H., J.F., and D.H. thank the Czech Science Foundation (grant number 17-08045S) and M.I.F.P., M.C.L, and J.A.S.L. thank the regional government Xunta de Galicia for financial support (Project Grupo Potencial Crecemento -GPC- ED431B 2017/59). J.M.O.-E. acknowledges financial support from the Spanish MICINN through project CTQ2018-094644-B-C22German Research Foundation; NA‐686/8Czech Science Foundation; 17‐08045SXunta de Galicia; ED431B 2017/5

Mechanical Stability Is Key for Large-Scale Implementation of Photocatalytic Surface-Attached Film Technologies in Water Treatment

[Abstract] Replacement of classical tertiary water treatment by chemical-free sunlight-driven photocatalytic units has been often proposed. Photocatalysts are required to be cost-effective, inert, chemically stable, reusable, and easy to separate and also that they are mechanically stable. The effect of mechanical stress on a photoactive TiO2 layer, and on its effectivity for degradation of phenol as a model pollutant, has been studied during photocatalytic water treatment using NUV–vis light. Sol–gel (SG) and liquid phase deposition (LPD) methods have been used to coat spherical glass beads with the photocatalyst (TiO2). Physicochemical characterization of coated glass beads has been performed by N2 adsorption–desorption isotherms, SEM, EDXS, and AFM. Phenol photocatalyzed degradation was carried out both in stirred batch and flow reactors irradiated with a medium-pressure Hg-vapor lamp (λ > 350 nm). Phenol concentration was determined by HPLC, and its photoproducts were identified using HPLC/MS. In the stirred batch reactor, all LPD-coated glass beads displayed higher catalytic activity than SG-coated ones, which increased with calcination temperature, 700°C being the most efficient temperature. Preliminary etching of the glass beads surface yielded dissimilar results; whereas, phenol photodegradation with SG-coated etched glass beads is twice faster than with unetched SG ones, the rate reduces to one-third using LPD etched instead of unetched LPD glass beads. Phenol photodegradation using LPD is similar both in stirred batch and flow reactors, despite the latter uses a lower catalyst load. LPD-etched catalyst was recovered and reused in the stirred batch reactor; its activity reduced sharply after the first use, and it also lost activity in successive runs, ca. 10% of activity after each “use and recover” cycle. In the flow reactor, activity loss after the first experiment and recycling (ca. 30%) was much larger than in the following runs, where the activity remained rather constant through several cycles. LPD is more adequate than SG for TiO2 immobilization onto glass beads, and their calcination at 700°C leads to relatively strong and reactive photocatalytic films. Still, TiO2-coated glass beads exhibited very low photoactivity compared to TiO2-P25 nanoparticles, though their separation is much easier and almost costless. The durability of the catalytic layer increases when using a flow reactor, with the pollutant solution flowing in a laminar regime through the photocatalyst bed. In this way, the abrasion of the photocatalytic surface is largely reduced and its photoactivity is better maintained.This research was partially supported by the Group React! and funded by the Ministerio de Economía y Competitividad (Spain, Project CTQ2015-71238-R MINECO/FEDER), and by the regional government of the Xunta de Galicia (Spain, Project GPC ED431B 2020/52)Xunta de Galicia; ED431B 2020/5

Oceanography of the Gulf of Artabro (northwestern Iberian Peninsula) in early spring: General patterns

The COPLA 393 cruise was carried out from 22-29 March 1993 on the continental shelf located between the Sisargas Islands and Cape Prior (northwest Spain). Forty-one stations distributed into five sections perpendicular to the coast were sampled, with the aim of investigating spring conditions in the Gulf of Artabro. Salinity and temperature profiles were obtained, and nutrients, chlorophyll, primary production, light, specific composition and abundance of plankton (including bacteria and phytoflagellates) were determined. The present study provides the first survey of conditions prevailing at the beginning of the spring in the entire Gulf of Artabro. The hydrographic situation is relatively complex, with a quite well defined thermic-saline front perpendicular to the coastline in the central part of the Gulf of Artabro. The water west of the frontal area was more saline (13.2 °C; 35.85 psu), whereas east of the front colder and less saline waters prevailed (12.8 °C; 35.75 psu). When the cruise was carried out, the primary production (35-155 mg C m⁻³ h⁻¹) and chlorophyll a concentration ( 2 mg m⁻³) were relatively low and a dispersion of the phytoplankton communities was observed. Mean biomass of the microzooplankton and the mesozooplankton were typical of winter (8.8 and 23 mg dw, respectively). Bacteria (1.5 X 10⁵ cel ml⁻¹) and microflagellates (phytoflagellate autotrophs: 790 cel ml⁻¹ and heterotrophs: 960 ml⁻¹) also had low abundances. The atmospheric conditions, which favoured an early spring bloom in February, had changed. There were areas with phytoplankton typical of winter, with predominance of microflagellates, cryptophyceae and small dinoflagellates, and other areas with low abundance of phytoplankton but with a high specific diversity. The latter were the remains of the spring bloom, which had occurred some days before the beginning of the cruise. Therefore, we suggest that the bloom-dispersion regime may be a common feature, existing normally in this gulf, as a consequence of the occurrence of early blooms in winter and the varying environmental conditions in the February-March period.La campaña COPLA 393 se llevó a cabo entre el 22 y el 29 de marzo de 1993 en la plataforma continental comprendida entre las islas Sisargas y el cabo Prior. Se muestrearon 41 estaciones distribuidas en cinco secciones perpendiculares a la costa. Su objetivo fue investigar las condiciones hidrográficas y la floración de primavera en el golfo de Artabro. Se obtuvieron perfiles de salinidad y temperatura, datos de nutrientes, clorofila, producción primaria, luz incidente, composición específica y cuantificación del plancton (in- cluyendo bacterias y fitoflagelados). Su estudio ha proporcionado, por primera vez en la totalidad del golfo de Artabro, información acerca de las condiciones reinantes al comienzo de la primavera. La situación hidrográfica es relativamente compleja, con un frente térmico y salino bastante bien definido perpendicular a la línea de costa en la parte central del golfo de Artabro. Hay agua más salina al oeste (13,2 °C; 35,85 ups) de la zona frontal y al este un cuerpo de agua más fría y de menor salinidad (12,8 °C y 35,75 ups). Cuando se llevó a cabo la campaña, la producción primaria (35-155 mg C m⁻³ h⁻¹) y la concentración de clorofila a ( 2 mg m⁻³) eran bajas y se observa una dispersión de las comunidades de fitoplancton. Tanto el microzooplancton como el mesozooplancton presentan biomasas medias típicas de invierno (8,8 y 23 mg de peso seco, respectivamente). También bacterias (1,5 X 10⁵ células ml⁻¹) y microflagelados (fitoflagelados autótrofos: 790 células ml⁻¹ y heterótrofos: 960 células ml⁻¹) mostraron bajas abundancias. Las condiciones atmosféricas que favorecieron una temprana proliferación primaveral de fitoplancton en febrero habían cambiado. Hay zonas con fitoplancton propio del invierno, con predominio de microflagelados, criptofíceas y pequeños dinoflagelados junto con otras de baja abundancia de fitoplancton, pero una alta diversidad específica. Son los restos de la floración primaveral que tuvo lugar días antes del comienzo de la campaña. Por ello, el régimen proliferación-dispersión debe darse corrientemente en este golfo como consecuencia de la proliferación temprana y de las cambiantes condiciones ambientales en febrero-marzo.Instituto Español de Oceanografí

Defect localization by an extended laser source on a hemisphere

The primary goal of this study is to localize a defect (cavity) in a curved geometry. Curved topologies exhibit multiple resonances and the presence of hotspots for acoustic waves. Launching acoustic waves along a specific direction e.g. by means of an extended laser source reduces the complexity of the scattering problem. We performed experiments to demonstrate the use of a laser line source and verified the experimental results in FEM simulations. In both cases, we could locate and determine the size of a pit in a steel hemisphere which allowed us to visualize the defect on a 3D model of the sample. Such an approach could benefit patients by enabling contactless inspection of acetabular cups.Peer reviewe

Inactivation of E. coli and S. aureus by novel binary clay/semiconductor photocatalytic macrocomposites under UVA and sunlight irradiation

The disinfection efficiency of several novel photocatalytic macrocomposites made of Ecuadorian clay mixed with two semiconductor materials (TiO2, ZnO) has been evaluated with Staphylococcus aureus and Escherichia coli as target bacteria. They have been tested under two irradiation sources (UVA lamp and sunlight) in different configurations. Two different semiconductor/clay ratios (60/40 and 80/20) were tested at 10–20 g·L–1 (with UVA) and 20–40 g·L–1 (with sunlight) composite loadings. With the presence of the photocatalyst, a four- to five-fold increase in the inactivation rate by UVA was observed with respect to single UVA inactivation, while the performance with sunlight reaches up to six-fold. The particular effect of nature, ratio and loading on the inactivation kinetics depends on the specific bacterial species tested. In this case, the inactivation of S. aureus was faster in comparison with E. coli, probably due to the interaction between bacteria and the catalytic material and the associated ζ-potential. In general, the 80% ZnO composites at maximum loading show the highest efficiency, comparable to that of nanosized semiconductors. The ability of these composites to maintain a high disinfection efficiency after three uses, together with their low cost and ease of recovery, make these composites an attractive option for wider use in water disinfection facilities

1-(3-Chloro-4-fluoro­phen­yl)-5-(2-diazo­acet­yl)-4-phenyl­pyrrolidin-2-one

In the title compound, C18H13ClFN3O2, the pyrrolidine ring adopts an envelope conformation and the planar part is rotated by 4.3 (6)° from the plane of the benzene ring and is almost perperdicular both to the diazo­acetyl unit [dihedral angle = 78.93 (7)°] and the phenyl ring [dihedral angle = 86.07 (7)°]. In the crystal, mol­ecules are linked into a three-dimensional framework by C—H⋯O inter­actions. The mol­ecular conformation is stabilized by an intra­molecular C—H⋯O hydrogen bond

Defect Localization By an Extended Laser Source on a Hemisphere

The primary goal of this study is to localize a defect (cavity) in a curved geometry. Curved topologies exhibit multiple resonances and the presence of hotspots for acoustic waves. Launching acoustic waves along a specific direction e.g. by means of an extended laser source reduces the complexity of the scattering problem. We performed experiments to demonstrate the use of a laser line source and verified the experimental results in FEM simulations. In both cases, we could locate and determine the size of a pit in a steel hemisphere which allowed us to visualize the defect on a 3D model of the sample. Such an approach could benefit patients by enabling contactless inspection of acetabular cups. © 2021, The Author(s).Open access funded by University of Helsinki Library

Slaughter weight rather than sex affects carcass cuts and tissue composition of Bisaro pigs

Carcass cuts and tissue composition were assessed in Bisaro pigs (n=64) from two sexes (31 gilts and 33 entire males) reared until three target slaughter body-weights (BW) means: 17 kg, 32 kg, and 79 kg. Dressing percentage and backfat thickness increased whereas carcass shrinkage decreased with increasing BW. Slaughter weight affected most of the carcass cut proportions, except shoulder and thoracic regions. Bone proportion decreased linearly with increasing slaughter BW, while intermuscular and subcutaneous adipose tissue depots increased concomitantly. Slaughter weight increased the subcutaneous adipose tissue proportion but this impaired intramuscular and intermuscular adipose tissues in the loin primal. The sex of the pigs minimally affected the carcass composition, as only the belly weight and the subcutaneous adipose tissue proportions were greater in gilts than in entire males. Light pigs regardless of sex are recommended to balance the trade-offs between carcass cuts and their non-edible compositional outcomes.Work included in the Portuguese PRODER research Project BISOPORC – Pork extensive production of Bísara breed, in two alternative systems: fattening on concentrate vs chesnut, Project PRODER SI I&DT Medida 4.1 “Cooperação para a Inovação”. The authors are grateful to Laboratory of Carcass and Meat Quality of Agriculture School of Polytechnic Institute of Bragança ‘Cantinho do Alfredo’. The authors are members of the MARCARNE network, funded by CYTED (ref. 116RT0503).info:eu-repo/semantics/publishedVersio