Broad Channel Research Articles

Engineering 2D multi-hetero-interface in the well-designed nanosheet composite photocatalyst with broad electron-transfer channels for highly-efficient solar-to-fuels conversion

The hetero-interface quality and area in the semiconductor heterostructure are important to the photocatalytic performance of the heterostructure. The 2D hetero-interface between two 2D semiconductors has been widely proved to enhance the photocatalytic performance, because the larger contact area of the hetero-interface can effectively improve the charge separation behavior. However, engineering high-quality 2D multi-hetero-interface in the well-designed semiconductor composite to further enhance the charge separation and utilization is still a big challenge. Herein, we constructed the 2D multi-hetero-interface in the well-designed nanosheet (NS) composite photocatalyst through an in-situ oxidation treatment combined with the electrostatic self-assembly strategy. The negatively-charged binary Ti3C2Tx/(001)TiO2 heterojunction NSs with the intimate 2D contact interface was fabricated through a facile in-situ oxidation method, while the protonated g-C3N4 NSs were positively charged. Thus, the spontaneous electrostatic attraction behavior between the above opposite-charged materials of the Ti3C2Tx/(001)TiO2 heterojunction and the g-C3N4 NSs enables the 2D multi-hetero-interface to be constructed in the Ti3C2Tx/(001)TiO2/C3N4 NSs. As such, the 2D multi-hetero-interface offers broad electron-transfer channels to enhance the charge separation and utilization. Upon simulated sunlight irradiation, the optimal Ti3C2Tx/(001)TiO2/C3N4 NSs achieved about 4-fold enhancement on the photocatalytic H2 generation and 3-fold improvement on the photocatalytic CO2 reduction as compared to the pure (001)TiO2 or g-C3N4 NSs.

Comb-shaped anion exchange membranes: Hydrophobic side chains grafted onto backbones or linked to cations?

In order to investigate the relationship between the side chain topology of comb-shaped anion exchange membranes (AEMs) and membranes properties, two types of hydrophobic side chains attached AEMs that based on QAPPO are synthesized, namely side chains grafted onto backbones and side chains tethered to cations, resulting in AxSB-QAPPO and AxSC-QAPPO AEMs, respectively. Compared with AxSC-QAPPO, the side chains in AxSB-QAPPO AEMs are more inclined to facilitate the membranes to form broad and interconnected ion channels, promoting ion conduction and providing more free volume for the external water to enter the membranes, which are benefit to improving the ionic conductivity and chemical stability of the AxSB-QAPPO samples. At 80 °C, the OH− conductivity of A8SB-QAPPO is 101.2 mS cm−1, while the values for A8SC-QAPPO and QAPPO are only 56.1 and 48.5 mS cm−1 respectively. After the stability test, the weight and IC retentions of A8SB-QAPPO are 83.0% and 77.0%, respectively, while the values for A8SC-QAPPO are 76.5% and 68.0%, respectively, and the values for QAPPO are 56.0% and 42.0%, respectively. Besides, the influence of side chain length on the membranes properties is studied. The chemical stability for both AxSB-QAPPO and AxSC-QAPPO AEMs is enhanced by increasing the side chain length from 5 to 14. After the stability test, the IEC retentions of A5SB-QAPPO, A8SB-QAPPO, A14SB-QAPPO, A5SC-QAPPO, A8SC-QAPPO and A14SC-QAPPO are 60.0%, 78.0%, 90.0%, 49.0%, 70.0% and 75.0%, respectively. While for ionic conductivity, the AEMs with the side chain length of 8 exhibit the highest OH− conductivity. Hence, we speculate that the comb-shaped AEMs with hydrophobic side chains attached to backbones (AxSB-QAPPO) are superior to the membranes with the side chains linked to cations (AxSC-QAPPO), and the membranes performance can be further optimized by adjusting the side chain length.

Controls on the stratal architecture of lacustrine delta successions in low‐accommodation conditions

AbstractLake‐delta deposits in low‐accommodation conditions are only a few metres thick and in some cases non‐existent. Fluvial channels occur in many cases directly on top of fine‐grained lacustrine deposits with delta deposits apparently missing. The geomorphology and stratigraphy of modern deltas in Lake Eyre, Australia, and Lake Chad in Africa indicate that delta shorelines can develop in lakes, but in many cases build out into low‐accommodation settings due to highly dynamic lake‐water levels. This work suggests that low‐accommodation is critical in the development of lacustrine delta deposits and that high (frequency and magnitude) rates of lake‐level change result in ’telescoping’ deltas, the deposits of which are thin but extensive. The telescopic deltas have conformable beds, but with abrupt vertical facies changes; this apparent stratigraphic contradiction is the result of long horizontal distance translation of the depositional system. Details of two lacustrine units, in Uinta Basin in the USA and Junggar Basin in China, both of which show characteristics of telescoping, are used to develop a process based stratigraphic model for the deposits of such lake deltas. Lacustrine facies comprise cross‐stratified, ripple cross‐laminated, structureless or graded and sharp‐based sandstone beds, mudstone (structureless, laminated, rippled, rich in organic content), carbonate mudstone, ooid packstone and stromatolites. Three facies associations are critical for lake delta stratigraphy: channelized distributary deposits that occur in the delta topset; lake plain deposits that represent the fluvial overbank deposits and the subaerially exposed (at low lake level) lake deposits; and fine‐grained, lacustrine deposits. A key corollary of the proposed low‐gradient, telescoping lacustrine delta model is that broad and shallow channels dominate the system, but that decimetre to metre thick, gently dipping delta‐front beds form subtle deposits along the margins of the lakes. These delta depocentres migrate basinward and landward at high rates (tens of kilometres each year), building thin (metres) but laterally extensive (tens of kilometres) sandstone units through multiple transgression–regression cycles.

Ocean melting of the Zachariae Isstrøm and Nioghalvfjerdsfjorden glaciers, northeast Greenland

Zachariae Isstrøm (ZI) and Nioghalvfjerdsfjorden (79N) are marine-terminating glaciers in northeast Greenland that hold an ice volume equivalent to a 1.1-m global sea level rise. ZI lost its floating ice shelf, sped up, retreated at 650 m/y, and experienced a 5-gigaton/y mass loss. Glacier 79N has been more stable despite its exposure to the same climate forcing. We analyze the impact of ocean thermal forcing on the glaciers. A three-dimensional inversion of airborne gravity data reveals an 800-m-deep, broad channel that allows subsurface, warm, Atlantic Intermediate Water (AIW) (+1.[Formula: see text]C) to reach the front of ZI via two sills at 350-m depth. Subsurface ocean temperature in that channel has warmed by 1.3[Formula: see text]C since 1979. Using an ocean model, we calculate a rate of ice removal at the grounding line by the ocean that increased from 108 m/y to 185 m/y in 1979-2019. Observed ice thinning caused a retreat of its flotation line to increase from 105 m/y to 217 m/y, for a combined grounding line retreat of 13 km in 41 y that matches independent observations within 14%. In contrast, the limited access of AIW to 79N via a narrower passage yields lower grounded ice removal (53 m/y to 99 m/y) and thinning-induced retreat (27 m/y to 50 m/y) for a combined retreat of 4.4 km, also within 12% of observations. Ocean-induced removal of ice at the grounding line, modulated by bathymetric barriers, is therefore a main driver of ice sheet retreat, but it is not incorporated in most ice sheet models.

Ion exchange properties of natural titanium silicate caryochroite (Na,Sr)3{(Fe,Mg)2+10(OH)6[TiO(Si6O17)(OH)0.5]2}·8H2O with a 1D system of parallel wide channels: Experimental study and theoretical analysis of the topochemical mechanisms

Ion-exchange properties of natural caryochroite (Na,Sr) 3 {(Fe,Mg) 2+ 10 (OH) 6 [TiO(Si 6 O 17 )(OH) 0.5 ] 2 }·8H 2 O, a microporous heterophyllosilicate with a one-dimensional system of broad zeolytic channels, related to nafertisite Na 3 {Fe 2+ 10 (OH) 6 [TiO(Si 6 O 17 )F 0.5 ] 2 }·2H 2 O, were studied in reactions with 1 N aqueous solutions of Rb, Cs, Ag, and Pb nitrates at 50 °C. In reactions with Rb + , Cs + , and Pb 2+ , sodium is partly replaced by nearly equivalent amounts of larger cations. In reactions with Pb 2+ and Ag + , additional processes involving H 2 O molecules take place: replacement of two H 2 O molecules with Pb 2+ + 2OH − and replacement of H 2 O molecule with Ag + + OH − , respectively. The geometrical-topological analysis of ion migration pathways in the nafertisite-type structures carried out using an approach based on the Voronoi-Dirichlet partition has shown that only Na + cations occurring at the centers of wide channels can take part in reactions with large alkaline cations proceeding in counter flows. In the reaction with Ag + , additional Na + ions are involved. Li + cations having a smaller radius can pass through the window between the channels, forming a 2D conducting layer. • Ion-exchange properties of natural titanosilicate caryochroite, a microporous heterophyllosilicate with a one-dimensional system of broad zeolytic channels, were studied in reactions with 1 N aqueous solutions of Rb, Cs, Ag, and Pb nitrates at 50 °C. • Three kinds of Na + cations in the caryochroite structure play different role in ion migration processes. • Li + cations having a smaller radius can pass through the window between the channels, forming a 2D conducting layer.

An ultrastructural study of the ovary cord organization and oogenesis in the amphibian leech Batracobdella algira (Annelida, Clitellata, Hirudinida)

This study reveals the ovary micromorphology and the course of oogenesis in the leech Batracobdella algira (Glossiphoniidae). Using light, fluorescence, and electron microscopies, the paired ovaries were analyzed. At the beginning of the breeding season, the ovaries were small, but as oogenesis progressed, they increased in size significantly, broadened, and elongated. A single convoluted ovary cord was located inside each ovary. The ovary cord was composed of numerous germ cells gathered into syncytial groups, which are called germ-line cysts. During oogenesis, the clustering germ cells differentiated into two functional categories, i.e., nurse cells and oocytes, and therefore, this oogenesis was recognized as being meroistic. As a rule, each clustering germ cell had one connection in the form of a broad cytoplasmic channel (intercellular bridge) that connected it to the cytophore. There was a synchrony in the development of the clustering germ cells in the whole ovary cord. In the immature leeches, the ovary cords contained undifferentiated germ cells exclusively, from which, previtellogenic oocytes and nurse cells differentiated as the breeding season progressed. Only the oocytes grew considerably, gathered nutritive material, and protruded at the ovary cord surface. The vitellogenic oocytes subsequently detached from the cord and filled tightly the ovary sac, while the nurse cells and the cytophore degenerated. Ripe eggs were finally deposited into the cocoons. A comparison of the ovary structure and oogenesis revealed that almost all of the features that are described in the studied species were similar to those that are known from other representatives of Glossiphoniidae, which indicates their evolutionary conservatism within this family.

The use of credit cards among low- and middle-income individuals in Colombia and the channels of monetary policy

Data for a retail credit card, which enables customers to finance purchases of semi-durable and non-durable goods, are used to show the way in which monetary policy and other interest rates affect the credit limits, the probability of use, and the value of purchases. This credit card, targeted at low- and middle-income individuals, is held by a quarter of employed labour force in Bogotá. Permanent and transitory incomes play an intuitive role in these three dimensions of the credit card. Credit limits are determined by the intervention interest rate, which supports the presence of the lending channel. The probability of use is determined by the usury interest rate while monthly purchases are affected by the interest rate charged by the financial institution and the usury interest rate, both indicative of the broad credit channel. Interestingly, after considering the customer’s observable characteristics, macroeconomic environment matters, mainly the labour market performance.

Nickle nanocrystals decorated on graphitic nanotubes with broad channels for fire hazard reduction of epoxy resin

Carbon nanotubes (CNTs) are a sort of carbon-based nanofillers blended into polymer nanocomposites to improve both of the flame retardancy and mechanical properties. However, the CNTs tend to entangle into bundles and the channels are too narrow to allow the entry of polymer chains, harmful to the dispersion and interaction within the polymer matrix. Therefore, by means of a facile pyrolysis method, boron and nitrogen co-doped larger-diameter graphitic nanotubes with decorated nickel nanocrystals (Ni/GNTs) were developed as flame retardant for epoxy resin (EP). The nanotubes are short but with large specific surface area. Compared to the commercial CNTs, the epoxy chain could infiltrate into the channels of Ni/GNTs which was approved by different techniques. The unique nanostructure endowed the product with strong interaction with the polymer matrix. The fire behaviors were examined by cone calorimeter tests, and the results showed that with the addition of 2 wt% Ni/GNTs, the peak of heat release rate and the total smoke production values of the nanocomposites were reduced by 43.5 % and 22.8 % compared with those of pure epoxy, respectively. Meanwhile, the flexural and tensile properties of EP/Ni/GNTs were also enhanced.

Impact of Monetary Policy on Private Investment: Evidence from Vietnam’s Provincial Data

This study sheds new light on the relationship between monetary policy and private investment using Vietnam’s provincial data and a system generalized method of moment (GMM) framework. To capture monetary policy’s effect, different indicators, viz. money supply, domestic credit to the private sector, interest rate and exchange rate are examined. We find that private investment is positively affected by respective monetary policies through broad money, domestic credit and interest rate channels, yet no credible evidence regarding the exchange rate’s effect. In which, such a surprising co-movement between real interest rate and private investment was illuminated through analysis of the economy’s distinctive characteristics over the two development stages (pre- and post-2012). Another notable finding is that economic development prospects of localities, which attract great attention and cause an intense competition between domestic and foreign investors, appear to be a major barrier to investment decisions of private firms.

Controls on microbial and oolitic carbonate sedimentation and stratigraphic cyclicity within a mixed carbonate‐siliciclastic system: Upper Cambrian Wilberns Formation, Llano Uplift, Mason County, Texas, USA

AbstractThe upper Cambrian Wilberns Formation in central Texas records deposition on a low‐gradient shelf within a mixed carbonate–siliciclastic tidal‐flat system that changes offshore to subtidal shelf and open‐marine oolitic skeletal shoals with large microbial mounds. Siliciclastic sediment is interpreted to have been delivered to the tidal flat by aeolian processes because of the narrow range in grain size and paucity of clay. Tidal influence is dominant as evidenced by reversing currents and desiccation on the tidal flat, and megaripples with reversing current indicators in offshore shoals. Intraclastic conglomerates were deposited in broad channels on the tidal flats during storm surges. Microbialite deposition is interpreted to be controlled by accommodation favouring amalgamated thin biostromes developed in the tidal flat vs. larger mounds with greater synoptic relief in the offshore, and current energy resulting in preferential elongation of offshore mounds in a NE–SW orientation. Intertidal mounds and biostromes grew in the presence of significant siliciclastic flux and trapped it within their structure, whereas offshore large buildups incorporated little siliciclastic component. Oolite and skeletal grainstone formed in tide agitated shoals associated with large subtidal microbial mounds. Storms extensively recycled and redistributed skeletal and oolitic sands from the offshore shoals across the shelf as thin sand sheets. Spatial mixing of siliciclastic and carbonate sediment occurred across the tidal flat and shelf. Low‐frequency and intermediate‐frequency stratigraphic cycles were driven by shifts in the shoreline and changes in rate of siliciclastic flux in response to relative sea‐level fluctuation. Random facies stacking and the lack of metre‐scale cyclicity are interpreted to reflect stratigraphic incompleteness and an episodic signal introduced by storms.

An Implicit Coupled 1D/2D Model for Unsteady Subcritical Flow in Channel Networks and Embayment

In this study, 1D and 2D shallow-water models were coupled to simulate unsteady flow in channel networks and embayment. The 1D model solved the 1D shallow-water equations (St. Venant) using the Preissmann box method and targeted long narrow reaches of the river networks, while the 2D model targeted broad channels and embayment and solved the 2D shallow-water equations using a semi-implicit scheme applied to an unstructured grid of triangular cells. The 1D and 2D models were solved simultaneously by building a matrix for the free surface elevation at every 1D junction and 2D cell center. Velocities were then computed explicitly based on the results at the previous time step and the updated water level. The originality of the scheme arose from a novel coupling method. The results showed that the coupled 1D/2D model produced identical results as the full 2D model in classical to benchmark problems with considerable savings in computational effort. Application of the model to the Pearl River Estuary in southern China showed that complex patterns of tidal wave propagation could be efficiently modeled.

Ranking of the Lena River Sections by the Complexity of Channel Processes and of Their Management

We substantiate the use of the previously developed methods to classify sections of the largest river (Lena) from the types of channel processes and special aspects of their management, i. e. water resource use, exploitation of the river as the water transport way, development of riverine areas and construction of river crossings for service lines. For assessing the complexity of river channel reconfguration and implementing regulatory measures we use certain indicators of channel stability, the channel pattern, river runoff, conditions of effective discharge, composition of bed-material load, occurrence of riffes and characteristics of their regime. It is shown that the indicator of complexity of channel processes management is represented by the amount of channel dredging performed to ensure normal navigation conditions. On the Lena river (from the Osetrovo port to the estuary) there are 10 reaches which differ both in the features and the degree of complexity of channel processes and, accordingly, in the conditions for their management. The study identifed the most diffcult (for channel management) sections; for the broad foodplain, unstable and compound braided channel we determined the main water management and water transport problems associated with channel processes.

Effects of Forming Gas Annealing and Channel Dimensions on the Electrical Characteristics of FeFETs and CMOS Inverter

In this study, ferroelectric FETs (FeFETs) and CMOS inverters are fabricated and analyzed, exhibiting 13% of 593 devices with sub-60 mV subthreshold swing (SS) at room temperature. Forming gas annealing (FGA) is found to not only enhance ferroelectricity but also significantly improve FeFET electrostatics. The experimental results indicate that FeFET with a narrow width shows weaker ferroelectric properties, and SS of sub-60 mV/dec with ID change less than two orders of magnitude. However, FeFET with a broad channel width reveals stronger ferroelectric properties, and SS of sub-60 mV/dec is over 2 orders of magnitude of Id. Finally, typical voltage transfer characteristics (VTCs) of a FeFET CMOS inverter with double sweeps at various VD from 0.6 to 2 V are demonstrated. The results show that hysteresis in a FeFET CMOS inverter could have both clockwise (CW) and counter-clockwise (CCW) loops.

Deep‐water sediment transport patterns and basin floor topography in early rift basins: Plio‐Pleistocene syn‐rift of the Corinth Rift, Greece

AbstractOur current understanding on sedimentary deep‐water environments is mainly built of information obtained from tectonic settings such as passive margins and foreland basins. More observations from extensional settings are particularly needed in order to better constrain the role of active tectonics in controlling sediment pathways, depositional style and stratigraphic stacking patterns. This study focuses on the evolution of a Plio‐Pleistocene deep‐water sedimentary system (Rethi‐Dendro Formation) and its relation to structural activity in the Amphithea fault block in the Corinth Rift, Greece. The Corinth Rift is an active extensional basin in the early stages of rift evolution, providing perfect opportunities for the study of early deep‐water syn‐rift deposits that are usually eroded from the rift shoulders due to erosion in mature basins like the Red Sea, North Sea and the Atlantic rifted margin. The depocentre is located at the exit of a structurally controlled sediment fairway, approximately 15 km from its main sediment source and 12 km basinwards from the basin margin coastline. Fieldwork, augmented by digital outcrop techniques (LiDAR and photogrammetry) and clast‐count compositional analysis allowed identification of 16 stratigraphic units that are grouped into six types of depositional elements: A—mudstone‐dominated sheets, B—conglomerate‐dominated lobes, C—conglomerate channel belts and sandstone sheets, D—sandstone channel belts, E—sandstone‐dominated broad shallow lobes, F—sandstone‐dominated sheets with broad shallow channels. The formation represents an axial system sourced by a hinterland‐fed Mavro delta, with minor contributions from a transverse system of conglomerate‐dominated lobes sourced from intrabasinal highs. The results of clast compositional analysis enable precise attribution for the different sediment sources to the deep‐water system and their link to other stratigraphic units in the area. Structures in the Amphithea fault block played a major role in controlling the location and orientation of sedimentary systems by modifying basin‐floor gradients due to a combination of hangingwall tilt, displacement of faults internal to the depocentre and folding on top of blind growing faults. Fault activity also promoted large‐scale subaqueous landslides and eventual uplift of the whole fault block.

Behavior of Catapleiite under Heating and Crystal Structure of its High-Temperature Transformation Product, a New Phase Na6Zr3[Si9O27] with Nine-membered Rings of SiO4 Tetrahedra

Thermal behavior of catapleiite, ideally Na2ZrSi3O9 ⋅ 2H2O, has been investigated with the X-ray diffraction, electroconductivity measurements using impedance spectroscopy, dynamic scanning calorimetry, thermal gravimetry, and infrared spectroscopy. The high-temperature transformation product of catapleiite obtained after annealing of catapleiite at 1000°C has been studied. This is a new microporous zirconosilicate, ideally Na6Zr3[Si9O27], representing a new structural type. It is hexagonal, P63/mcm, a = 11.5901(9), c = 9.9546(9) A, V = 1158.05(16) A3. Its crystal structure model has been obtained using single-crystal X-ray diffraction data and refined by the Rietveld method on the basis of the powder X-ray diffraction data (R = 3.87%). The structure is based on the heteropolyhedral framework, which substantially differs from that of catapleiite and is built by nine-member rings Si9O27 formed by SiO4 tetrahedra linked with isolated ZrO6 octahedra. Extraframework Na cations are located in broad channels of the framework and between the tetrahedral Si9O27 rings.

Nanocomposite electrodes for high current density over 3\u2009A\u2009cm\u22122 in solid oxide electrolysis cells

Solid oxide electrolysis cells can theoretically achieve high energy-conversion efficiency, but current density must be further increased to improve the hydrogen production rate, which is essential to realize widespread application. Here, we report a structure technology for solid oxide electrolysis cells to achieve a current density higher than 3 A cm−2, which exceeds that of state-of-the-art electrolyzers. Bimodal-structured nanocomposite oxygen electrodes are developed where nanometer-scale Sm0.5Sr0.5CoO3−δ and Ce0.8Sm0.2O1.9 are highly dispersed and where submicrometer-scale particles form conductive networks with broad pore channels. Such structure is realized by fabricating the electrode structure from the raw powder material stage using spray pyrolysis. The solid oxide electrolysis cells with the nanocomposite electrodes exhibit high current density in steam electrolysis operation (e.g., at 1.3 V), reaching 3.13 A cm−2 at 750 °C and 4.08 A cm−2 at 800 °C, corresponding to a hydrogen production rate of 1.31 and 1.71 L h−1 cm−2 respectively.

DYNAMICS OF WOUND HEALING AFTER INTRAORAL PIERCING WITH MEDICAL STEEL CLIPS IN EXPERIMENTAL ANIMALS

Introduction. In modern dentistry, medical steel, along with other materials used for dental implantation, is considered as biocompatible or bio-tolerant materials. Among the commonest complications caused by piercing, there are hypertrophic scarring, pain, swelling and infection. Therefore, the research on clinical and morphological changes in tongue and cheek tissues during experimental piercing with medical steel clips on animals and further evaluation of the consequences of this procedure seem to be quite relevant. The purpose of the study was to determine the effect of clips made of medical steel on the dynamics of the wound healing in tissues of the cheek and tongue following the implantation in test animals. Materials and methods. The experiment was conducted on the chinchilla line rabbits (n=8) in 2015. The animals were implanted with medical steel clips in soft tissue of the tongue and cheeks. Histological studies were performed on 7th, 14th, 28th and 60th days following the implantation to study the dynamics of the change in the pierced channel. Results and conclusions. The study has shown the purulent process in the tongue and cheeks tissues following the implantation of medical steel clips can be observed from the 7th to 60th days. Thus, we can suggest that the damaging effect of medical steel clips on tongue and cheek tissues in the test animal promotes purulent inflammation. The rabbits with implanted clips in the tongue and cheek had broad wound channels, containing purulent exudates, inflammatory infiltrates were found in the walls of the wound channel. During the experiment, the histological specimens of the cheeks and tongue showed a large amount of granulation tissue, signs of immaturity and secondary inflammation, slow transformation of granulation tissue into the connective tissue that causes a lack of complete epithelisation and promotes deep skin wounds. The impairment of nerve endings in the form of oedema of the endo- and perineuria as a consequence of the implantation of medical steel clips can be manifested by persistent pain syndrome, loss of local sensitivity and distortion of taste sensation. In future, we are planning to investigate the dynamics of the wound healing after intraoral implantation of clips made of other materials in the test animals.

Unmanned Aerial Vehicles (UAVs) for Monitoring Macroalgal Biodiversity: Comparison of RGB and Multispectral Imaging Sensors for Biodiversity Assessments

Developments in the capabilities and affordability of unmanned aerial vehicles (UAVs) have led to an explosion in their use for a range of ecological and agricultural remote sensing applications. However, the ubiquity of visible light cameras aboard readily available UAVs may be limiting the application of these devices for fine-scale, high taxonomic resolution monitoring. Here we compare the use of RGB and multispectral cameras deployed aboard UAVs for assessing intertidal and shallow subtidal marine macroalgae to a high taxonomic resolution. Our results show that the diverse spectral profiles of marine macroalgae naturally lend themselves to remote sensing and habitat classification. Furthermore, we show that biodiversity assessments, particularly in shallow subtidal habitats, are enhanced using six-band discrete wavelength multispectral sensors (81% accuracy, Cohen’s Kappa) compared to three-band broad channel RGB sensors (79% accuracy, Cohen’s Kappa) for 10 habitat classes. Combining broad band RGB signals and narrow band multispectral sensing further improved the accuracy of classification with a combined accuracy of 90% (Cohen’s Kappa). Despite notable improvements in accuracy with multispectral imaging, RGB sensors were highly capable of broad habitat classification and rivaled multispectral sensors for classifying intertidal habitats. High spatial scale monitoring of turbid exposed rocky reefs presents a unique set of challenges, but the limitations of more traditional methods can be overcome by targeting ideal conditions with UAVs.

Unconventional monetary policy and the credit channel in the euro area

We disentangle credit supply and demand and we then embed this information into a Bayesian threshold VAR model to investigate the importance of the demand channel and the broad credit channel in the transmission of unconventional monetary policy on the macroeconomy during financial stress periods. We find that during such periods, UMP shocks boost aggregate demand for loans, increase agents’ net worth and revitalize credit to firms and households. In addition, counterfactual analysis suggests that non-standard policy measures aiming at stimulating loan demand and relaxing banks’ balance sheet constraints would provide a significant support to economic activity, prices and the financial sector.

Three-Dimensional Stable Cation-Exchange Membrane with Enhanced Mechanical, Electrochemical, and Antibacterial Performance by in Situ Synthesis of Silver Nanoparticles.

In this study, a simple and facile approach was proposed to synthesize silver nanoparticles (AgNPs) loaded cation-exchange membranes (CEMs). A wide analytical study involving scanning electronic microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy was accomplished to corroborate that the in situ generated AgNPs were uniformly dispersed in the polymer matrix. In addition, as a result of the proposed synthesis strategy, the cross-linking structure inside the membrane was formed. The proper particle size and dispersibility of the AgNPs improved the mechanical properties of the membranes. Besides, the optimal AgNP-loaded CEM exhibited excellent bacterial killing activities against Gram-negative bacteria and showed a controlled improvement in the electrochemical performance of the prepared membranes. These effects were caused by the obtained distribution of AgNPs near ion-exchange groups that increased the aggregation of water molecules around them, improving the efficiency of ion transport due the formation of array broad ion-transport channels. The optimized CEM [sulfonated polysulfone (60SPSF)-C3#-Ag-2] exhibited an enhanced NaCl removal ratio of 67.5% with a high current efficiency (96.9%) and a low energy consumption (5.84 kWh kg–1). The distance of the inhibition zone from the boundary of the membrane of SPSF-C3#-Ag-2 reached 4.8 mm. These results led us to suggest that the proposed synthesis strategy may have potential applications in the field of antibacterial and desalting ion-exchange membranes.