Search

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents a new concept of A 2 B 2 O 7 pyrochlore materials design dedicated to thermal barrier coating based on the simultaneous use of several structural mechanisms responsible for phonon wave scattering. The basis for these analyses is the La 2 O 3 -Gd 2 O 3 -ZrO 2 ternary system, in which a smaller Gd3+ gadolinium atom was introduced into the La 2 Zr 2 O 7 compound in the substitution position A, with the simultaneous introduction of an excess B atom (Zr4+) and its partial localisation in position A. This resulted in the cumulative effect of the difference in mass and radius of rare earth elements cations, with the simultaneous formation of a non-stoichiometric type of lattice and the rattling effect. Initially, this effect was achieved using substitution atoms with a much smaller radius, such as Tm3+ or Yb3+, but without creating non-stoichiometric structures. Such systems were also characterised by a strong tendency to decompose into pyrochlore and fluorite phases. Using a new approach, a phase-stable material with ultra-low thermal conductivity was obtained, with a two-phase structure, which, however, was not formed as a result of the compound's decomposition but is the result of the presence of excess Zr4+ and a shift in the ternary system to the two-phase region. As a result, a material with extremely low thermal conductivity and a course independent of temperature increase was obtained, which suggests the maximum level of crystal lattice defect. In addition, thermal conductivity was effectively reduced by using relatively cheap rare earth oxides, reducing their amount compared to pyrochlore compounds based on lanthanum with ytterbium or thulium. [ABSTRACT FROM AUTHOR]

The prediction of the underwater-radiated noise for a vessel is classically performed at a model scale and extrapolated by semi-empirical laws. The accuracy of such a method depends on many parameters. Among them, the acoustic propagation model used to estimate the noise measured at a model scale is important. The present study focuses on the impact of the presence of a source in the transverse plane. The scattering effect, often neglected in many studies, is here investigated. Applying different methods for computation, we perform several simulations of the acoustic pressure field to show the influence of the scattered field. We finally discuss the results and draw some conclusions about the scattering effect in our experimental configuration.

The prediction of the underwater-radiated noise for a vessel is classically performed at a model scale and extrapolated by semi-empirical laws. The accuracy of such a method depends on many parameters. Among them, the acoustic propagation model used to estimate the noise measured at a model scale is important. The present study focuses on the impact of the presence of a source in the transverse plane. The scattering effect, often neglected in many studies, is here investigated. Applying different methods for computation, we perform several simulations of the acoustic pressure field to show the influence of the scattered field. We finally discuss the results and draw some conclusions about the scattering effect in our experimental configuration. [ABSTRACT FROM AUTHOR]

Based on the plane–strain assumption, a calculation model of pile–soil–pile vertical coupling vibration response considering the scattering effect of passive piles is established in this paper. Using this model, the vertical displacement expressions of pile core soil and pile surrounding soil, soil displacement attenuation function, and longitudinal complex impedance are obtained. Then, based on the strict pile–soil coupling effect, the displacement of the active pile under vertical load and scattering effect, as well as the displacement of the passive pile under incident waves, are solved separately. A new type of dynamic interaction factor for pipe group piles is derived by introducing scattering effect factors. A numerical example shows that the degenerate solution in this paper is in good agreement with the existing solution, which verifies the rationality of the solution. Considering the scattering effect is helpful in improving the accuracy of vibration response analysis of pile groups. The variation in parameters such as slenderness ratio, pile spacing, and outer diameter has significant effects on the interaction factor, and compared with the solid pile, the influence of parameter change on the pipe pile is smaller. [ABSTRACT FROM AUTHOR]

Manganese-Zinc (Mn-Zn) ferrite is a ceramic and soft magnetic material, which can be, used for the fabrication of passive elements integrated in power converters. The main, challenge related to these converters rely on their miniaturization and efficiency, enhancement. Digital Light Processing (DLP) is a potential additive manufacturing, technique to fabricate fine and complex Mn-Zn ferrite components. This paper focuses, on the analysis of the optical properties of the formulations containing Mn-Zn ferrite, powder. Different particle's sizes (71–1.3 µm) were used to study the influence of the, cured monolayer evolution and the optical properties of the ferrite. We compared, experimental data obtained on formulations with a low content of ferrite particles, (15%.wt) to the results issued from the Mie theory. High solid content (75%.wt) were, investigated to cover the practical applications of DLP and the role of light scattering, was analyzed and discussed in detail for this specific configuration. [ABSTRACT FROM AUTHOR]

Herein, a facile method is reported to fabricate a color conversion layer comprised of zinc oxide nanoparticles (ZnO NPs) and quantum dots (QDs) for micro-light emitting diode (μ-LED) displays. Further, 11-mercaptoundecanoic acid (MUA)-treated ZnO NPs (ZnO@MUA NPs) are synthesized via a high-energy ball milling method, which bypasses the need for complex synthesis processes and enables functional groups to attach to the surface, thereby facilitating the formation of ZnO@MUA NPs-QD hybrid composites (ZQCs). The particle size, surface characteristics, elemental composition, and binding energy are analyzed to elucidate the reaction mechanism and to confirm that the fabricated ZQC exhibits a chemically bonded structure. To ascertain the optimal molar concentration for incorporating the QDs, parameters such as QD bonding efficiency, quantity of bonded QDs, interparticle distance, and absolute photoluminescence quantum yield (PLQY) are evaluated as functions of molar concentration. As a result, the optimal molar concentration is found to be 1930 nM, giving a bonding efficiency of 96.8 %, along with the bonded QDs of 1.51 × 1011 per a unit area of 1 mm2 of ZnO NPs and a PLQY of 64.8 %. Furthermore, comprehensive optical analyses are performed to assess the potential of the ZQC as a color conversion material for μ-LED displays, in comparison to the use of pristine QDs and silica NP-QD composites. [Display omitted] • A novel color conversion material comprised of ZnO nanoparticles and quantum dots for displays. • Hybrid nanocomposite using MUA-treated ZnO nanoparticles via a high-energy ball milling method. • Outstanding enhancement in both the effective color conversion efficiency and color purity. [ABSTRACT FROM AUTHOR]

Based on the plane–strain assumption, a calculation model of pile–soil–pile vertical coupling vibration response considering the scattering effect of passive piles is established in this paper. Using this model, the vertical displacement expressions of pile core soil and pile surrounding soil, soil displacement attenuation function, and longitudinal complex impedance are obtained. Then, based on the strict pile–soil coupling effect, the displacement of the active pile under vertical load and scattering effect, as well as the displacement of the passive pile under incident waves, are solved separately. A new type of dynamic interaction factor for pipe group piles is derived by introducing scattering effect factors. A numerical example shows that the degenerate solution in this paper is in good agreement with the existing solution, which verifies the rationality of the solution. Considering the scattering effect is helpful in improving the accuracy of vibration response analysis of pile groups. The variation in parameters such as slenderness ratio, pile spacing, and outer diameter has significant effects on the interaction factor, and compared with the solid pile, the influence of parameter change on the pipe pile is smaller.

The seismic input is the basis for the seismic safety analysis of dams, but current seismic input methods have not reasonably considered the influence of canyon scattering effects on the dynamic response of dams. In this paper, the total motion field of the canyon is deconstructed into the free field of a uniform half space and the scattering field of the canyon and they are obtained separately. The indirect boundary integral equation method (IBIEM) is used to determine the scattering field of the canyon, which is superimposed with the free field to obtain the seismic ground motion field (total motion field) of the canyon. The accuracy of the total motion field of the canyon is verified through reference solutions. In the finite element analysis of seismic ground motion field in the canyon, the total motion field at the truncation boundary of the canyon foundation is transformed into the equivalent seismic input loads and the interior of the canyon are simulated using the finite element method (FEM). Then, based on the wave input for the free field combined with the viscoelastic artificial boundary, a new wave input method for the total motion field combined with the viscoelastic artificial boundary is established. The seismic wave input method based on the finite element-indirect boundary integral equation method is applied to numerically determine the seismic response of a trapezoidal canyon. The differences in the seismic response of the canyon under free-field input and total motion field input are discussed. The results show that there is a certain deviation between the displacement and waveform obtained from the free-field input and the solutions obtained from the indirect boundary integral equation method. There is a large error for a large angle of incidence, and the errors increase with increasing seismic wave frequency. When the incident angle is 60°, the maximum error in the frequency domain reaches 92.3 %, and the maximum error in the time domain reaches 250 %. The displacement amplitude and waveform of the canyon obtained from the total motion field input showed agreement with the results of the indirect boundary integral equation method. The wave input method established in this paper has high calculation accuracy and reasonably considers the scattering effect of canyons, which provides a basis for more accurate predictions of the seismic response of dams on canyon foundations. • The scattering field motion of canyon sites is determined. • The earthquake ground motion field of canyon sites is determined based on IBIEM. • The influence mechanisms of scattering effects of canyon sites are revealed. • A new wave input method considering the scattering effect of canyons is established. • The wave input method suiting for canyon sites has high calculation accuracy. [ABSTRACT FROM AUTHOR]

In this study, we fabricated a random nanostructure (RNS) external light extraction composite layer containing high-refractive-index nanoparticles through a simple and inexpensive solution process and a low-temperature mask-free process. We focused on varying the shape and density of the RNSs and adjusted the concentration of the high-refractive-index nanoparticles to control the optical properties. The RNSs fabricated using a low-temperature mask-free process can use the distance between the nanostructures and various forms to control the diffraction and scattering effects in the visible light wavelength range. Consequently, our film exhibited a direct transmittance of ~85% at a wavelength of 550 nm. Furthermore, when the RNSs' composite film, manufactured using the low-temperature mask-free process, was applied to organic light-emitting diodes (OLEDs), it exhibited an external quantum efficiency improvement of 32.2% compared with the OLEDs without the RNSs. Therefore, the randomly distributed high-refractive-index nanoparticles on the polymer film can reduce the waveguide mode and total reflection at the substrate/air interface. These films can be used as a scattering layer to reduce the loss of the OLED substrate mode. [ABSTRACT FROM AUTHOR]

The scattering phenomenon is known to be of great importance for the acoustic quality of a performance arts space. The scattering of sound can be achieved in different ways: it can be obtained by the presence of architectural and/or decorating elements inside a room (e.g., columns, statues), by the geometry and roughness of a surface (e.g., Quadratic Residue Diffuser (QRD)) and by the diffraction effect occurring when a sound wave hits the edges of an obstacle. This article deals with the surface scattering effects and the diffusion phenomenon only related to MDF and plywood panels tested by disposing the wells both horizontally and vertically. The test results undertaken inside a semi-reverberant room and inside a large reverberant room have been compared to highlight the success and the failure of the measuring methodologies. In detail, according to the existing standards and regulations (i.e., ISO 17497—Part 2), diffusion measurements have been undertaken on a few selected types of panel: two QRD panels (made of Medium Density Fiberboard (MDF) and plywood) with and without a smooth painted solid wood placed behind the QRD. The panels have been tested inside two rooms of different characteristics: a semi-anechoic chamber (Room A) and a large reverberant room (Room B). The volume size influenced the results that have been analyzed for both chambers, showing an overlap of reflections on panels tested inside Room A and a clear diffusion response for the panels tested inside Room B. In terms of the diffusion coefficient in all the octave bands between 125 Hz and 8 kHz, results should not be considered valid for panels tested in Room A because they were negatively impacted by extraneous reflections, while they are reliable for panels tested in Room B. [ABSTRACT FROM AUTHOR]

Abstract Coseismic electromagnetic (EM) signals that appear from the P arrival were observed in a volcanic area during the 2016 Kumamoto earthquake. In this study, we conduct numerical simulations to explain the coseismic EM signals observed for a M5.4 aftershock of the earthquake. Initially, we adopt a water-saturated half-space model, and its simulation result for a receiver with a depth of 0.1 m suggests that the magnetic signals do not show up at the arrivals of P, refracted SV–P and Rayleigh waves because the evanescent EM waves just counterbalance the localized magnetic signals that accompany P, refracted SV–P and Rayleigh waves. Then, we conduct numerical simulations on a seven-layer half-space model in which the second layer corresponds to an aquifer analogy and the six other layers refer to air-saturated porous media. When only the electrokinetic effect is considered, the simulated coseismic magnetic signals still appear from the S arrival. The combination of electrokinetic effect and surface-charge assumption is also tested. We find that signals before the S arrival are missing on the transverse seismic, transverse electric, radial magnetic and vertical magnetic components, although the situation on horizontal magnetic components is improved to an extent. Then, we introduce an artificial scattering effect into our numerical simulations given that the scattering effect should exist in the volcanic area. New numerical result shows good agreement with the observation result on the signal appearance time. Hence, the combination of electrokinetic and scattering effects is a plausible explanation of coseismic EM signals. Further investigations indicate that coseismic electric and/or magnetic signals are more sensitive to the scattering effect and the aquifer thickness than seismic signals.

This paper deals with the acoustic shielding of especially high-frequency sound by jet (Air Shield). In the shear layer of the jet, sound waves incident on the jet undergo reflection and / or scattering. We investigated the performance of the air shield with two methods. One method is the experiment of a sound source in static field with a finite width rectangular jet under subsonic speed. The other method is the numerical calculation with the similar condition with the experiment as a reference to understand the phenomenon of the experiment. The cause of sound attenuation under the air shield was discussed by considering a reflection model on the surface of jet and scattering effect in the shear layer of jet. As a result, it was found that the scattering occurred when the sound source frequency was 20kHz. When the sound source frequency was 5kHz, the reflectivity was close to the theoretical value. Because of these experimental results, the reduction effect can be obtained at the side, so it is best to install the air shield when the sound source at the position of the potential core as the air shield installation position.

The use of front‐face fluorescence spectroscopy, and three‐way chemometric analysis (like PARAllel FACtor analysis, PARAFAC), has been successfully applied for the analysis of unpretreated samples in the fields of food and environmental analysis. It would be desirable to evaluate the potential of this approach for the analysis of any real sample in any field of research. Even in the simplest of the real samples acquired with front‐face, the presence of scattering and inner filter effects will occur, potentially hampering the subsequent data analysis due to deviations from Beer‐Lambert's law. This paper addresses these concerns in practice, proposing a strategy of spectral preprocessing to mitigate these effects. This is done by measuring several data sets with different levels of scattering and inner filter effects by fluorescence in excitation‐emission mode. The results show that the occurrence of these interferents (sometimes neglected with front‐face mode) affects the fluorescence signal and interferes with any traditional analysis on these data, as much as they hamper the successful use of methods like PARAFAC. The proposed preprocessing strategy is based on one of the most traditional correction for the inner filter effect with right‐angle mode. However, we suggest applying a tunable factor, b, that will account for the degree of deviation from linearity between concentration of a given analyte and its fluorescence signal. It is demonstrated that by choosing a proper b‐value, this correction helps in finding an acceptable solution for the PARAFAC algorithm, in line with Beer‐Lambert's law. The behavior of PARAFAC for front‐face fluorescence analysis of data sets affected by scattering and inner filter effect is studied. The presence of inner filter and scattering highly affects the signals in front‐face fluorescence landscapes interfering both with traditional and chemometric analysis of the data. A strategy of spectral preprocessing is proposed that has proven to help finding an acceptable solution for the PARAFAC algorithm, if the appropriate value for the tunable parameter is chosen. [ABSTRACT FROM AUTHOR]

• Carbon fiber reinforced (CFR)-PEEK implants have been developed for spinal fixation in oncological disease. • CFR-PEEK implants constitute a feasible and effective way to restore stability as standard titanium. • Further studies are needed to clarify their potentially enormous oncological advantagess. In spinal oncology traditional titanium implants could significantly impair evaluation of postoperative imaging because of artifacts, potentially affecting proper planning and execution of radiotherapy and adequate radiological follow-up to rule out progression of the disease. This is why carbon fiber reinforced (CFR)-PEEK implants have been developed for spinal fixation. The advantages of this system include fewer artifacts on imaging, potentially improving the execution and quality of radiotherapy, with also a reduced scattering effect to neighboring tissues. A comparative clinical and radiological study between new CFR-PEEK and standard titanium implants is described. Data recorded for each case included patient demographics, clinical, radiological and surgical data, intra- and postoperative complications, follow-up information. The goal of this study was to verify the safety and effectiveness of CFR-PEEK devices compared to standard titanium implants. A total number of 78 patients were reviewed. 36 patients underwent CFR-PEEK fixation, while titanium implants were used for 42 patients. Functional recovery was obtained in both groups and registered at last follow-up in terms of axial pain and neurological status. No significative differences were found between the two groups in terms of post-operative clinical complications and hardware-related complications. CFR-PEEK implants constitute a feasible and effective way to restore stability in metastatic spine tumors. This study found a non inferior favorable profile in terms of intraoperative and postoperative complications and functional recovery, compared to titanium. Further prospective studies are needed to clarify the potential oncological advantage of their radiolucency. [ABSTRACT FROM AUTHOR]

• The EL efficiency of OLEDs is significantly improved by doping a solution processable multifunctional magnetic NPs Fe3O4@Au@SiO2 into PEDOT:PSS as composite HIL. • The efficiency increase mechanism is well analyzed by experimental characterization and theoretical simulation, which is finally attributed to the collective effects of light-scattering, localized surface plasmon resonance (LSPR) and the magnetic effect induced by the magnetic NPs in the HIL. Multifunctional nanomaterials have been widely utilized to optimize the performances of optoelectronic devices. In this work, magnetic composite nanoparticles (NPs) of Fe 3 O 4 @Au@SiO 2 are used as dopants to improve the quantum efficiency of electroluminescence of the tris-(8-hydroxyquinoline) aluminum-based organic light emitting devices (OLEDs). As a result, the performances of doped OLED (V on = 2.8 V, L = 23,400 cd/m2, EQE = 1.55) are obviously boosted as compared to the control device (V on = 2.9 V, L = 19,780 cd/m2, EQE = 1.27). Especially, the current efficiency of fluorescent green OLEDs can be 22.5 % enhanced by simply mixing the magnetic Fe 3 O 4 @Au@SiO 2 (0.5 wt‰) NPs into poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), yielding the maximum value of 4.62 cd/A. The efficiency enhancement could be attributed to the collective effects of light-scattering, localized surface plasmon resonance (LSPR) and magnetic effect induced by magnetic composite NPs. [ABSTRACT FROM AUTHOR]

The scattering phenomenon is known to be of great importance for the acoustic quality of a performance arts space. The scattering of sound can be achieved in different ways: it can be obtained by the presence of architectural and/or decorating elements inside a room (e.g., columns, statues), by the geometry and roughness of a surface (e.g., Quadratic Residue Diffuser (QRD)) and by the diffraction effect occurring when a sound wave hits the edges of an obstacle. This article deals with the surface scattering effects and the diffusion phenomenon only related to MDF and plywood panels tested by disposing the wells both horizontally and vertically. The test results undertaken inside a semi-reverberant room and inside a large reverberant room have been compared to highlight the success and the failure of the measuring methodologies. In detail, according to the existing standards and regulations (i.e., ISO 17497—Part 2), diffusion measurements have been undertaken on a few selected types of panel: two QRD panels (made of Medium Density Fiberboard (MDF) and plywood) with and without a smooth painted solid wood placed behind the QRD. The panels have been tested inside two rooms of different characteristics: a semi-anechoic chamber (Room A) and a large reverberant room (Room B). The volume size influenced the results that have been analyzed for both chambers, showing an overlap of reflections on panels tested inside Room A and a clear diffusion response for the panels tested inside Room B. In terms of the diffusion coefficient in all the octave bands between 125 Hz and 8 kHz, results should not be considered valid for panels tested in Room A because they were negatively impacted by extraneous reflections, while they are reliable for panels tested in Room B.

Coseismic electromagnetic (EM) signals that appear from the P arrival were observed in a volcanic area during the 2016 Kumamoto earthquake. In this study, we conduct numerical simulations to explain the coseismic EM signals observed for a M5.4 aftershock of the earthquake. Initially, we adopt a water-saturated half-space model, and its simulation result for a receiver with a depth of 0.1 m suggests that the magnetic signals do not show up at the arrivals of P, refracted SV–P and Rayleigh waves because the evanescent EM waves just counterbalance the localized magnetic signals that accompany P, refracted SV–P and Rayleigh waves. Then, we conduct numerical simulations on a seven-layer half-space model in which the second layer corresponds to an aquifer analogy and the six other layers refer to air-saturated porous media. When only the electrokinetic effect is considered, the simulated coseismic magnetic signals still appear from the S arrival. The combination of electrokinetic effect and surface-charge assumption is also tested. We find that signals before the S arrival are missing on the transverse seismic, transverse electric, radial magnetic and vertical magnetic components, although the situation on horizontal magnetic components is improved to an extent. Then, we introduce an artificial scattering effect into our numerical simulations given that the scattering effect should exist in the volcanic area. New numerical result shows good agreement with the observation result on the signal appearance time. Hence, the combination of electrokinetic and scattering effects is a plausible explanation of coseismic EM signals. Further investigations indicate that coseismic electric and/or magnetic signals are more sensitive to the scattering effect and the aquifer thickness than seismic signals. [ABSTRACT FROM AUTHOR]

A light extraction structure and a flexible electrode have been developed to enhance the electroluminescence (EL) efficiency of flexible organic light-emitting diodes (FOLEDs). However, these structures are still influenced by optical losses, poor electrical stability, and low throughput, and are not suitable to be adopted into FOLEDs due to the surface roughness problem, low flexibility/adhesion, complicated process, and high temperature/pressure process. Here, to solve these problems, we demonstrate embedded Ag nanowires (AgNWs) in flexible substrate and highly flexible random nano pattern via easy/low-cost solution form process at atmospheric pressure and low temperature without any additional material. This study demonstrates an internal and external light extraction structure composed of double-sided nano-dimpled substrate PVB (DndP), which is directly fabricated on both sides of a flexible substrate (polyvinyl butyral, PVB) only in itself without additional material via the easy/low-cost transferring process using the anodic aluminum oxide (AAO) template by an anodization process-based solution form at atmospheric pressure and low temperature. Therefore, because the DndP and the substrate are composed of the same material, PVB, there is no light loss between their interfaces. In addition, a high-refractive-index TiO 2 nanoparticle, for the scattering effect, and AgNWs, for electrode flexibility, are embedded into the DndP via the covering method using the solution form. Such structures exhibit extraordinary mechanical flexibility due to the AgNWs embedded in the PVB substrate. Therefore, FOLEDs using such structures can be well adapted to flexible/rollable/foldable displays and wearable application devices. Moreover, the corrugated surface of FOLEDs by such structures can improve the current flow through increased surface area of electrodes and extract the trapped light through the scattering effect (Rayleigh, Mie), reducing the total reflection and coupled photon in metal/dielectric. In addition, the FOLEDs with such structures show color/spectrum-stable property and independence of viewing angles owing to their random nature. The final green FOLEDs with DndP, embedded scattering TiO 2 nanoparticle, and embedded AgNWs&PEDOT:PSS demonstrate an outstanding EL efficiency enhancement ratio of 2.23 time via internal and external light extraction without electrical short. • Demonstration of double-sided nano-dimpled substrate (PVB) as internal and external light extraction structure to improve electroluminescence efficiency of flexible organic light-emitting diodes. • Using easy/low-cost transferring process and anodization process-based solution form at atmospheric pressure and low temperature without additional material. • Embedded high-refractive-index TiO 2 nanoparticle in PVB substrate to improve scattering effect. • Embedded Ag nanowires (AgNWs) in PVB substrate to solve flexibility/adhesion/surface roughness problem of device. [ABSTRACT FROM AUTHOR]

In this paper, Ag@SiO2 core-shell nanoparticles (NPs) with different shell thicknesses were prepared experimentally and introduced into the photosensitive layer of mesoscopic hole-conductor-free perovskite solar cells (PSCs) based on carbon counter electrodes. By combining simulation and experiments, the influences of different shell thickness Ag@SiO2 core-shell nanoparticles on the photoelectric properties of the PSCs were studied. The results show that, when the shell thickness of 0.1 wt% Ag@SiO2 core-shell nanoparticles is 5 nm, power conversion efficiency is improved from 13.13% to 15.25%, achieving a 16% enhancement. Through the measurement of the relevant parameters of the obtained perovskite film, we found that this gain not only comes from the increase in current density that scholars generally think, but also comes from the improvement of the film quality. Like current gain, this gain is related to the different shell thickness of Ag@SiO2 core-shell nanoparticles. Our research provides a new direction for studying the influence mechanism of Ag@SiO2 core-shell nanoparticles in perovskite solar cells.

Graphical abstract Highlights • Highly conductive polysiloxanes based electrolytes with different viscosities were studied in DSSCs. • Bimodal TiO 2 showed better pore infiltration and light harvesting while maintaining a high surface area. • Lower charge transfer resistance was obtained for the bimodal TiO 2. • Efficient and stable quasi-solid-state DSSCs are achieved. Abstract In this article, we discuss the effect of the polysiloxane-based poly(ionic liquid) (PIL) electrolytes viscosity on the infiltration into mesoporous and bimodal TiO 2 thin films with different thickness, and consequently on the DSSC performance. The mesoporous films contain small mesopores of 8–10 nm, resulted from the use of Pluronic P123 surfactant (SOFT), resulting in high surface area. The DUAL (soft/hard) templated films have unique bimodal porous structures comprising 8–10 nm mesopores and 60–70 nm macropores resulted from the use of P123 and 130 nm polystyrene beads, which encouraged the electrolyte pore infiltration and light harvesting. Electrochemical impedance spectroscopy confirms the lower charge transfer resistance of the DUAL templated TiO 2 films as opposed to SOFT TiO 2 electrodes which corresponds to higher DSSC efficiency, despite having lower dye adsorption thanks to the improved PIL electrolyte infiltration within larger pores. The addition of ionic liquids to PIL significantly lowers the viscosity, increases the ionic conductivity and I 3 − diffusion rate, resulting in noticeable improvement in photovoltaic performance in both SOFT and DUAL templated photoanodes for all the observed thickness. [ABSTRACT FROM AUTHOR]

In this study, Ag@SiO2 nanoparticles were synthesized by a modified Stöber method for preparing the TiO2 mesoporous layer of carbon counter electrode-based perovskite solar cells (PSCs) without a hole transporting layer. Compared with normal PSCs (without Ag@SiO2 incorporated in the TiO2 mesoporous layer), PSCs with an optimal content of Ag@SiO2 (0.3 wt. % Ag@SiO2-TiO2) show a 19.46% increase in their power conversion efficiency, from 12.23% to 14.61%, which is mainly attributed to the 13.89% enhancement of the short-circuit current density, from 20.23 mA/cm2 to 23.04 mA/cm2. These enhancements mainly contributed to the localized surface Plasmon resonance effect and the strong scattering effect of Ag@SiO2 nanoparticles. However, increasing the Ag@SiO2 concentration in the mesoporous layer past the optimum level cannot further increase the short-circuit current density and incident photon-to-electron conversion efficiency of the devices, which is primarily ascribed to the electron transport pathways being impeded by the insulating silica shells inside the TiO2 network. [ABSTRACT FROM AUTHOR]

Background: Protocols including combination of surgery and radiotherapy are more and more frequent in the treatment of bone tumors of the spine. In metastatic disease, combination of surgery and radiotherapy is since long time accepted, as based on clinical evidence. In primary tumors, combination of surgery and radiotherapy can be considered in all the cases in which a satisfactory oncological margin cannot be achieved: high-grade malignancies, recurrent tumors, huge tumors expanding in an extracompartimental area, and when tumor-free margin requires unacceptable functional sacrifices. However, metal implants are an obstacle in the collaboration between surgeons and radiation oncologists. Carbon-fiber-reinforced polyethil-ether-ether-ketone (CFR-PEEK) composite implants could make easier and more effective the treatment as radiolucent and not interfering with ionizing radiation and accelerated particles. The purpose of this article is to report the preliminary results from a cohort of patients treated with CFR-PEEK and to evaluate the safety and the non-inferiority of the device respect the commonly used titanium implants.Materials and Methods: This study concerns an ambispective cohort series of 34 tumor patients (14 metastases and 20 primaries, most of them recurrent) submitted to thoracic and lumbar spine fixation with a CFR-PEEK composite implants. Oncologic surgery was palliative decompression and fixation in 9 cases, tumor excision in 21, and enbloc resection in 4. Data collected for this preliminary report were all intraoperative remarks, incidence of complications, changes in neurological status, local control, and survival. All the cases were followed 6-36 months (mean 13 months).Results: Only one intraoperative screw breakage occurred out of 232 implanted screws. Pain control and neurological improvement were the early clinical results. Two sacral screws loosening were found at 9 and 12 months in multilevel constructs performed on multirecurrent tumors. Six local recurrences were early found thanks to the implant radiolucency. Radiation oncologists' opinion was favourable as concerning better treatment planning on CT and lacking of scattering effect during the treatment.Conclusions: No artifacts on imaging studies mean early local recurrence detection. For radiation oncologists, no artifacts on imaging studies mean easier planning and no scattering effect means more effective and safe radiotherapy, particularly when particles are used. Moreover, it seems that the clinical use of CFR-PEEK composite implants may be safe and at least comparable with the commonly used titanium implants in terms of intraoperative complications, stability at weight bearing and at functional recovery. Larger patient series and longer follow-up are required to confirm these data. [ABSTRACT FROM AUTHOR]

Scattering effects are ubiquitous in practical wireless optical links. Here a transmission model with complete consideration of scattered light and beam wandering effects for underwater link is developed, with the aim to completely characterize the received quantum state of light through dense scattering medium. Based on this model, we show the influence of scattered photons on the improvement of the entanglement after transmission through turbid water may vary for different copropagation scenarios, i.e., the contribution of scattered light on entanglement transmission may be turned from positive to negative, with increase of the strength of underwater beam wandering. And the attenuation coefficient and aperture size are found to be the dominant factors affecting the entanglement through underwater link. While for the counterpropagation scenario, the scattered photons will severely deteriorate the entanglement transmission especially for the high-loss scattering links. These findings may shed light on quantum entanglement transmission and help to develop its applications through dense scattering medium.

The power conversion efficiency (PCE) of TiO 2 -based dye-sensitized solar cells (DSSCs) could be enhanced by modification of photoanodes. The effective blocking layer addition, one-dimensional nanostructure architecture, and scattering material design are the most important approaches to provide the high PCE of DSSCs and are critically reviewed in this work. The blocking layer generated the energy barrier can suppress the recombination of an electron in photoanode. One-dimensional (1D) nanostructures of a nanorod, nanotube and nanowire, promote the enhanced electron transport of DSSCs. The PCE of 1D nanostructure based DSSCs can potentially be improved by incorporating high surface area TiO 2 nanoparticles and constructing the multilayered 1D nanostructure arrays photoanodes. The scattering effect can be generated by mesoporous, core-shell and yolk-shell materials with the sizes architecture corresponding to the wavelength of incident light, enhancing the light harvesting. The high efficiency of TiO 2 -based photoanodes could be realized by optimizing the composition, size of materials, and thickness of photoanodes. [ABSTRACT FROM AUTHOR]

TiO 2 nanostructures with unique morphology, pseudo-square shaped, non-aggregated and exposed facets are of great interest in several fields including photovoltaic applications. In particular, 1-D TiO 2 nanorod or 2-D TiO 2 nanosheet based dye-sensitized solar cells (DSSCs) often show promising photovoltaic performance due to their 1-D and 2-D morphologies, respectively. Therefore, exploring TiO 2 with new nanostructure is essential. In this work, we report the synthesis of non-aggregated anatase TiO 2 nanoplates with {1 1 1} facets from TiOF 2 crystals by two-step hydrothermal process. The prepared TiO 2 nanoplates were employed as a supplementary light scattering layer in the photoelectrode, which resulted in 10% improvement in the photovoltaic performance of DSSC in comparison with the photoelectrode without TiO 2 scattering layer. Such improvements were attributed to the enhancement in light scattering due to the pseudo-square shaped 2-D plate-like morphology, higher dye loading, increase in electron lifetime and the decrease in electron recombination, which were examined by photovoltaic characterization, impedance analysis, UV–vis diffuse reflectance and absorbance spectra. [ABSTRACT FROM AUTHOR]

Potassium sulfide doped with silver (K 2 S:Ag) nanoparticles were used in bulk heterojunction organic solar cells to assist in harvesting more photons using an absorber layer composed of poly (3-hexylthiophene) and (6,6)-phenyl-C 61 -butyric acid methyl ester blend (P3HT:PCBM). The optical and electrical properties of the organic-molecule-blended thin photoactive films were investigated using optical spectrometers and a computer-interfaced source meter coupled with a solar simulator. The structure and composition of the nanoparticles were examined by high resolution scanning and transmission electron microscopies. The measured photovoltaic parameters indicated that solar cell performance was dependent on the concentration of K 2 S:Ag nanoparticles in the P3HT:PCBM blended film. Consequently, enhanced photocurrent was recorded from the devices with a short circuit current as high as 15.8 mA cm−2, fill factor of 57.2%, and power conversion efficiency of 5.12%, representing a 15% and 97% growth in fill factor and power conversion efficiency, respectively, compared to the reference device. The results were attributed to the occurrence of localized surface plasmon resonance and the light scattering effect of K 2 S:Ag in the photoactive medium. • Significant PCE growth has been recorded using K2S:Ag in P3HT:PCBM blend OSC. • Reduced charge recombination was attained by K2S:Ag in organic solar cells. • Organic solar cell has the potential to produce cheap and flexible solar panels. [ABSTRACT FROM AUTHOR]

The luminescent solar concentrator (LSC) absorbs large areas of solar photons and directs the down-converted fluorescence into solar cells for power generation.Enabling LSCs to effectively utilize the solar spectrum while maintaining a high degree of aesthetics is the key to their future applications.Here, the InP/ZnS quantum dots (QDs) are dropped into off-stoichiometric thiol-ene (OSTE) polymers for the fabrication of the LSC device.The effect of doping concentrations on the trade-off between optical efficiency and aesthetic properties has been discussed.A sufficient concentration of QDs is required to utilize more solar energy.However, due to the high concentration of QDs in the LSC device, attentions need to be paid to the scattering effect that degrades the optical performance and induces the deterioration of aesthetic parameters.When the QD concentration is 1.6 × 10−2 mg/mL, LSC obtains the optimal optical efficiency of 2.7%.The excellent aesthetic parameters with the color rendering index (CRI) of 92.94 and the average visible transmittance (AVT) of 81.87% are maintained at the same time.We anticipate that this work sheds light on design optimization for achieving high optical efficiency LSC devices with excellent aesthetic parameters. • The InP/ZnS QDs-based LSCs with thiol-ene polymers are fabricated. • The effect of QD concentration on optical and aesthetic properties is discussed. • The optical efficiency of 2.7% is achieved under the optimal QD concentration. • The aesthetic parameters with CRI of 92.94 and AVT of 81.87% are obtained. [ABSTRACT FROM AUTHOR]

Enhancing outcoupling efficiency and stabilizing emission spectra are of high technical importance in realizing high quality white transparent organic light emitting diodes (TOLEDs). In this work, we demonstrate a random nano-scattering layer (RSL) as a structure which can effectively address those tasks. The RSL contributes to bottom and top emissions by scattering and reflection, respectively. With the use of RSL, we achieved remarkable total efficiency enhancement of 101%. Also, a viewing angle independent stable white spectrum with a color rendering index of 79 was achieved. With its straight forward processing, our RSL can be readily applied to deal with various photonic applications to enhance both efficiency and emission spectra. [ABSTRACT FROM AUTHOR]

In thin film solid-state heterojunction solar cells (HSCs), titanium-dioxide (TiO 2 ) electrodes need to be optimized to have large specific surface area, controllable pore sizes, and superior light scattering properties. In this study, we synthesize hierarchical nanoporous TiO 2 beads with sub-micron diameters by a template-free, fast, and low-temperature synthetic scheme to satisfy the aforementioned requirements for HSCs. These nanoporous TiO 2 beads are composed of numerous TiO 2 nano crystallites that provide mesopores, and the inter-particle distances of size-controlled TiO 2 beads can provide additional controllable macropores. We report the first successful application of TiO 2 bead films (SP250, SP450) with controllable hierarchical nanostructure to be sensitized with Sb 2 S 3 for all-solid-state heterojunction solar cells (Sb-HSCs). The Sb-HSCs made using the controlled TiO 2 beads as photoanodes exhibit a superior light-to electricity conversion efficiency of 4.8%, yielding more than 15% enhancement in comparison with that (3.6%) of commercial TiO 2 nanoparticle (NP40) electrodes. The well-tailored photoanode with high surface area, fewer grain boundaries, multi-scale pore structure, and enhanced optical scattering results in much better infiltration of hole-conducting materials, decreased recombination with increased electron lifetime, and enhanced light scattering, which result in the enhanced photovoltaic properties. [ABSTRACT FROM AUTHOR]

A near-infrared (940 nm) image of skin tissue can be substantially enhanced using optical scanning technology (OST) that can reduce the scattering effect and remove the wrinkles or fine hair in the image. Using OST to create the skin tissue image ensured that the contour of blood vessels became more clear than that obtained from the divergent light source. In addition, the oxygen saturation of the blood vessels and tissues obtained using OST were approximately 98.65 and 93.17%, respectively, exhibiting an increase of more than 20% compared with that obtained using divergent light, and approached the value when measured using commercial pulse oximetry. Because the proposed method has a deep light penetration depth and high image intensity and resolution for oxygen saturation analysis, it is highly appropriate to be applied to future studies on diabetes and cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Optical scattering by biological tissues largely deteriorates the efficiency of the Raman analysis of these tissues. To evaluate the effect of scattering on Raman depth profiles (RDPs), we developed a simple method using a thin-layered sample mimicking real tissues and a conventional Raman microscope. The sample comprised three layers: a silicon wafer, a thin aqueous film containing Intralipid particles as scatters, and a fused silica window; this design was used to mimic real skin tissues quantitatively. The multi-scattering effect, which deteriorates spatial resolution, was clearly observed as broadening of RDPs. Decrease in Raman intensity was also systematically examined as a function of both the concentration of the Intralipid particles and depth of the film, and evaluated using Lambert-Beer's law. The abovementioned observations can be quantitatively explained on the basis of the scattering cross-section and concentration of the Intralipid particles, indicating that the method is useful for the quantification of the deterioration of Raman measurements due to optical scattering. [ABSTRACT FROM AUTHOR]

Sodium yttrium fluoride (NaYF4) nanoparticles (NPs) have been used to enhance the performance of optoelectronic devices such as polymer solar cells (PSCs). In this paper, we propose and demonstrate short circuit density (Jsc) enhancement induced by scattering and up-conversion (UC) effect of NPs in PSCs. The NaYF4 NPs were doped in active layer, functioning as highly efficient additive for improving the light harvesting, which leads to significantly increased photocurrent and power conversion efficiency (PCE) of inverted PSCs. The absorption spectrum shows that the doping devices have much stronger absorption, which is in accord with IPCE and transmittance spectrum. The absorption and electric field profile of the devices with or without NaYF4 NPs were performed using finite difference time domain (FDTD) simulation. It is approved that the NaYF4 NPs result in the absorption improvement by scattering and UC effect. [ABSTRACT FROM AUTHOR]

The sub-microspheres play multiple roles in enhancing dye adsorption and light-scattering to improve the performance of dye-sensitized solar cells (DSSCs). In this work, the well-defined 2 sub-microspheres with anatase granular-like nanocrystals are prepared in high yield by combining hydrolytic process with solvothermal treatment. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results indicated that plenty of rhombic nanoparticles with ~ 18 nm diameter having mutual contacts to neighboring nanoparticles were densely self-assembled into sub-microspheres, and abundant mesopores existed in the whole sub-microspheres with superior light scattering ability. The appropriate pore diameter and relatively high specific surface area of the as-obtained sub-microsphere result in a higher dye adsorption. As expected, by using the sub-microspheres as a scattering layer, a higher photovoltaic conversion efficiency of 10.15% is obtained for DSSCs. The sub-microspheres play multiple roles in enhancing dye adsorption and light-scattering to enhance the performance of dye-sensitized solar cells. In this work, the well-defined TiO2 sub-microspheres with anatase granular-like nanocrystals are facilely and reproducibly prepared in high yield by combining hydrolytic process with solvothermal treatment. The obtained sub-microspheres with appropriate pore diameter and relatively high specific surface area result in a larger amount of dye adsorption. [ABSTRACT FROM AUTHOR]

Abstract: NaYF4:Yb3+, Er3+ nanocomposites (NCs) are synthesized by a facile solvothermal approach and doped into PCDTBT:PCBM blend as a bifunctional additive to improve peformance of inverted polymer bulk heterojunction (BHJ) solar cells. The dependence of device performance on NaYF4:Yb3+, Er3+ NCs in the blend film is investigated. The results show that the short-circuit current density is apparently enhanced by doping NaYF4:Yb3+, Er3+ NCs into the active layer while maintaining the open-circuit voltage and fill factor, leading to an increase in power conversion efficiency. NaYF4:Yb3+, Er3+ NCs acts two kinds of roles for light absorption enhancement. Up-conversion (UC) emission from Yb3+ sensitized Er3+ dopants in the NaYF4:Yb3+, Er3+ NCs is observed. The photocurrent generated from UC near 980nm excitation can improve the utilization of solar photons in the near infrared (NIR). The scattering effect of NaYF4 nanoparticles (NPs) enhances the light absorption in visible region. The performance of polymer solar cell doped with NaYF4:Yb3+, Er3+ NCs is compared with that of undoped. The concept of integrating UC and scattering functionality into active layer suggests a promising and practical pathway for improving visible and NIR absorption of polymer solar cells. [Copyright &y& Elsevier]

Highlights: [•] ZnO micro-flowers were synthesized by a simple solution deposition method. [•] ZnO micro-flowers were used as scattering layer for dye-sensitized ZnO solar cells. [•] ZnO micro-flowers/nanoparticles bilayer solar cell has much higher conversion efficiency due to scattering effect. [ABSTRACT FROM AUTHOR]