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Investigation of different potential instability phenomena is an essential part of a study of the structural behaviour of double-layer braced barrel vaults. In this context, the effects of the use of a reinforced concrete (RC) topping in composite action with double-layer grid-works on the instability behaviour of such structures were studied. Two types of double-layer flat grids and barrel vaults were considered: without any integral RC topping (non-composite grid-works) and with a RC topping in composite action with the spatial grid (composite grid-works). The primary models were selected and designed adopting a consistent procedure utilising the weight–density method. Initially, elastic buckling analyses were performed. Complementary studies included a series of non-linear finite-element analyses accounting for geometric and material non-linearities emphasising structural stability and the post-buckling behaviour. It was found that the presence of a rather thin layer of RC covering, in composite action with double-layer grids, increased both the initial buckling and the ultimate strengths of such structures substantially, and also significantly improved their post-buckling behaviour, resulting in much improved reliability against progressive failure and sudden loss of strength.

A thin and broadband frequency selective surface (FSS)-based magnetic absorber is presented for low-microwave frequency applications. The design consists of a double-layers of FSS with the combination of two different magnetic substrates, which provides a much broader bandwidth compared to existing single-layered designs. The magnetic materials are in-house made by mixing different ratios of carbonyl-iron powder with silicone elastomer polydimethylsiloxane (PDMS). The simple single-square loop (SSL) structure is used for both FSSs which are printed on a standard FR4 material using lossy resistive sheet. This configuration allows the use of a closed-form equivalent-circuit model for a fast and efficient bandwidth optimization. A genetic algorithm (GA) is utilized to obtain the design parameters for broadband absorption with minimum overall thickness. The measured results confirm that the proposed absorber operates from 0.78 to 4.8 GHz with -10 dB reflectivity. The design achieves 144% fractional-bandwidth with a 10.12 bandwidth-to-thickness ratio.

In this paper, several computer simulations have been carried out using lumerical FTDT software. As a result, the optimal layer thicknesses for antireflection coatings SiC/MgF2 and SiC/ZnO/MgF2 deposited on the surface of polished silicon were determined. Among the considered coatings, the double layer structure SiC (60 nm) + MgF2 (110 nm) has the lowest reflection (

The double-layer a-IGZO thin film transistors (DL-TFTs) using a quantum well channel and a top barrier can reduce the subthreshold swing and hysteresis by 0.73 $\times$ and 0.13 $\times$ , respectively, in the transfer characteristics using the bottom gate sweep as compared to the single-layer TFTs (SL-TFTs). The wide bandgap barrier on top of the narrow bandgap IGZO channel serves as a protection layer between the IGZO channel and the SiO2 top gate insulator to prevent plasma-induced damage on the IGZO channel caused by the S/D metal etching and the top gate insulator deposition. As for the mobility using the bottom gate operation with the top gate grounded, the DL-TFTs show higher mobility (1.06 $\times$ ) at the room temperature due to less Coulomb scattering caused by the plasma-induced damage for percolation conduction, while the SL-TFTs have higher mobility at low temperatures due to the improved hopping efficiency for thermally activated hopping. The hysteresis is temperature independent down to 160 K, indicating the electrons tunneling between the channel and the top gate insulator is dominant. As for the reliability, DL-TFT has a smaller Vth shift than SL-TFT under both positive bias temperature stress (PBTS) due to less subgap defect in the channel.

Surface complexation models (SCM), based mainly on the diffuse double layer (DDL) theory, have been used to predict zeta potential at the crude oil-brine-rock (COBR) interface with limited success. However, DDL is inherently limited in accurately predicting zeta potential by the assumptions that all the brine ions interact with the rock surface at the same plane and by the double layer collapse at higher brine ionic strength (>1M). In this work, a TLM-based SCM captured zeta potential trends at the calcite-brine interface with ionic strength up to 3 M. An extended DDL and TLM-based SCMs were used to predict the electrokinetic properties of a composite carbonate rock showing a different mineralogical composition. The extended TLM-based SCM captured the zeta potential prediction trends and magnitude, highlighting the contribution of the inorganic minerals and organic impurities on the composite carbonate surface. In contrast, the extended DDL-based SCM captured the zeta potential trends but failed to capture the magnitude of the measured zeta potential. Interestingly, the TLM-based SCM predicted a positive SP for the rock-brine interface, which could explain the oil-wet nature of composite carbonate rocks due to electrostatic adsorption of negatively charged carboxylic acids. Conversely, the DDL-based SCM predicted a negative SP, leading to an inaccurate interpretation of the electrokinetic properties at the rock-brine interface. Thus, the use of extended TLM-based SCM was required to accurately predict the zeta potential and account for the adsorption of carboxylic acids on the reservoir composite carbonate surface.

Functionalisation of technological nanopores and investigation of their transport properties have attracted considerable interest from scientific as from technological point of view, among others due to their potential regarding molecular transport design. Asymmetric design of nanopore structure and functionalisation is expected to trigger increased and directed transport of ionic species. Based on this motivation, we demonstrate a layer-selective polymer functionalisation in a mesoporous double layer thin film to generate nanoscale step gradient architectures with asymmetric charge distribution by taking advantage of co-condensation and polymer modification techniques. Thereby, mesoporous silica and co-condensed mesoporous amino silica thin films are combined to double layered films with a film thickness of 300 – 400 nm in both sequential arrangements, respectively. Iniferter initiated polymerisation is used to selectively functionalise only the amino silica layer with polymers such as poly(2-(methacryloyloxy)ethyltrimethylammonium chloride) (PMETAC) in a grafting from approach. Investigation of the ionic pore accessibility of the mesoporous double layered films before and after layer-selective polymer functionalisation shows that the ionic pore accessibility is dominated by the bottom layer when overcoming the electrostatic repulsion of the top layer.

Background: Telmisartan and rosuvastatin calcium fixed-dose combination double-layer tablet is used for hypertension and hyperlipidemia treatment. Owing to the critical problem in establishing the specificity, precision, and accuracy of the USP analysis method and simultaneous analysis method for both components, an analysis method that could be applied to researchers in the field is urgently needed. Objective: To develop and validate a reversed phase-high-performance liquid chromatography method for the quantitative analysis of dissolution samples of telmisartan and rosuvastatin calcium fixed-dose combination double-layer tablets, as a hypertension and hyperlipidemia treatment. Methods: The developed analysis method was validated according to USP Category I requirements. The validity of the quantitative assay of the dissolution test solution was determined based on the system suitability, specificity, linearity, accuracy, precision, and solution stability of the assay for the components. Results: The developed method was selective and precise. The retention times of telmisartan and rosuvastatin calcium was 8.1 min and 2.8 min, respectively, and system suitability was 0.217 and 0.17, respectively. Both components showed linearity at 10–120% concentration. The accuracy and precision were also within acceptable limits. The drugs in the dissolution samples were stable for a long time, no interaction occurred between the excipients and active pharmaceutical ingredients, and no interference was observed in the analysis. Conclusion: The quantitative analysis of the double-layered formulation of telmisartan and rosuvastatin calcium was accurate, selective, and precise. Therefore, this method can be recommended for use in the industrial quality control of telmisartan and rosuvastatin calcium formulations.

The work presented in this paper concerns a method for the miniaturized frequency selective surface (FSS) based on the meander lines. A miniaturized dual-bandstop FSS structure based on meander lines with spiral-shape is proposed and simulated. The equivalent circuit and current distributions are introduced to explain the FSS performance. The size of the unit cell is 10 mm, which is about 0.037 wavelength at the first resonant frequency. Simulation results indicate that the proposed FSS has a frequency shift smaller than 1% for different polarizations with an oblique incident angle of 60°. A prototype of the FSS is fabricated and measured. The measurement results show that the FSS is polarization-insensitive and angle-insensitive.

Circular dichroism (CD) is widely used in enantiomer identification, photodetection, and circular polarization devices. Improving the CD signal of easily prepared 3D chiral nanostructures by design...

An inverse patchy colloid (IPC) refers to a particle having patches that are mutually repulsive while the bare particle–patch interactions are attractive. We model a system of charged IPCs with a s...

To reveal the engineering relationship among the electrical properties of embroidered conductive lines, the electrical properties and arrangements of conductive yarns, it is necessary to establish their equivalent resistance model. Embroidered conductive lines in textiles are usually fabricated by single-layer (conductive and nonconductive yarn used as upper and lower yarn) or double-layer embroidery technology (conductive yarns used as upper and lower yarn). Several researchers have proposed the simple resistance model for single-layer embroidered conductive line based on geometric structure of single conductive yarn in fabric. However, the double-layer conductive line has the contact resistance periodically interlaced by the upper and lower conductive yarns, and it made its equivalent circuit different from that of single-layer conductive line. In this work, a geometric model was built to describe the trace of conductive yarn in fabric, and in combination with Wheatstone Bridge theory, was applied to establish the equivalent resistance models of double-layer conductive lines with a certain width, consisted of various courses. First, the equivalent resistance model of double-layer conductive lines consisting of single course was proposed to calculate the contact resistance. Then, to obtain the electrical resistance of double-layer conductive lines with a certain width, the equivalent resistance model was extended from single course to multiple courses ([Formula: see text]). Finally, to validate the proposed equivalent resistance model, double-layer conductive lines with different embroidery parameters (stitch length and stitch spacing) on nonwoven fabric were fabricated and evaluated. The experimental results revealed that the proposed model accurately predicted the resistances of double-layer conductive lines.

Heterogeneous electrocatalysis and molecular redox catalysis have developed over several decades as two distinct ways to facilitate charge-transfer processes essential for energy conversion and storage. Whereas electrocatalytic reactions are driven by the applied voltage, molecular catalytic processes are driven by the difference between standard potentials of the catalyst and the reactant. Here, we demonstrate that the rate of electron transfer between a dissolved reactant and a molecular catalyst immobilized directly on the surface of a carbon nanoelectrode is governed by combination of chemical driving force and electrostatic potential drop across the double layer. DFT calculations show that varying the applied voltage alters the potential drop between the surface-bound and dissolved redox species. These results suggest a new route for designing next-generation hybrid molecular/electrocatalysts.

Low-efficiency charge transfer is a critical factor to limit the photocatalytic H2 evolution activity of semiconductor photocatalysts. The interface design is a promising approach to achieve high charge-transfer efficiency for photocatalysts. Herein, a new 2D/2D atomic double-layer WS2/Nb2O5 shell/core photocatalyst (DLWS/Nb2O5) is designed. The atom-resolved HAADF-STEM results unravel the presence of an unusual 2D/2D shell/core interface in DLWS/Nb2O5. Taking advantage of the advanced femtosecond-resolved ultrafast TAS spectra, the average lifetime of charge carriers for DLWS/Nb2O5 (180.97 ps) is considerably shortened as compared to that of Nb2O5 (230.50 ps), strongly indicating that the 2D/2D shell/core interface enables DLWS/Nb2O5 to achieve ultrafast charge transfer from Nb2O5 to atomic double-layer WS2, thus yielding a high photocatalytic H2 evolution rate of 237.6 μmol/h, up to 10.8 times higher than that of pure Nb2O5 nanosheet. This study will open a new window for the development of high-efficient photocatalytic systems through the interface design.

Specific ion effects play a vital role in a variety of colloidal and interfacial processes. However, few studies have reported the specific ion effects in the humus aggregation process, which strongly influence the transport and fate of environmental pollutants. In this study, soil humus colloids were prepared and characterized, and the specific ion effects on humus aggregation in electrolyte solutions were investigated at a variety of concentrations and pH values using dynamic light scattering methods. Activation energy (ΔE), which is known to reflect the dynamics and stability of a colloidal system, was used to quantitatively characterize the specific ion effects. The results showed that given ΔE value of 2.48 × 103 J mol−1 at pH 3.0, the electrolyte concentrations were 91.6, 58.2, 3.8, and 0.8 mmol L−1 for Na+, K+, Mg2+, and Ca2+, respectively, thus indicating significant specific ion effects in the humus aggregation process. Most importantly, decreasing the electrolyte concentrations increased the differences in the ΔE value between two cation species with the same valence (i.e., ΔENa – ΔEK and ΔEMg – ΔECa), while increasing the pH increased the magnitude of ΔEMg – ΔECa. However, the classic Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory and the double layer theory, as well as the currently widely used ionic hydration and dispersion effects, failed to predict the experimentally observed increase in the specific ion effects with decreasing electrolyte concentrations in a quantitative sense. These results have implications for the necessity of involving specific ion effects for a better understanding of humus aggregation and interactions in aqueous and soil systems.

Background: The main objective was to compare the outcome of single layer interrupted extra-mucosal sutures with that of double layer suturing in the closure of colostomies. Subjects and Methods: Sixty-seven patients with closure colostomy were assigned in a prospective randomized fashion into either single layer extra-mucosal anastomosis (Group A) or double layer anastomosis (Group B). Primary outcome measures included mean time taken for anastomosis, immediate postoperative complications, and mean duration of hospital stay. Secondary outcome measures assessed the postoperative return of bowel function, and the overall mean cost. Chi-square test and student t-test did the statistical analysis.. Results: Thirty-two patients were allocated to group A and 35 patients to group B. The mean time taken for anastomosis was significantly shorter in group A (23.25 ± 1.20 min in group A vs. 36.71 ± 1.93 min in group B; P

We consider a double-layer structure consisting of a bilayer graphene sheet and a two-dimensional electron gas, isolated in a very thin GaAs quantum well. The collective excitations are determined from the zeroes of the dynamical dielectric function within the random-phase approximation, taking into account the temperature effects. Numerical calculations present that two plasmon modes exist in the system, similar to those in other double-layer structures. While the optical mode continues in the interband single-particle excitation area, the acoustic mode only crosses the intraband single-particle excitation boundary and disappears. Also, our investigations show that plasmon properties in the system are affected significantly by most of the chosen factors. Plasmon frequency increases as the separation increases while the increase in carrier density decreases noticeably these frequencies. Temperature affects plasmon characters similarly to but more weakly than that does in monolayer grapheme—two-dimensional electron gas double-layer structures. Finally, the temperature can increase the effects of some other parameters on plasmon properties of the system, so this factor should be taken into account in calculations to improve the model for better results.

The ice-breaking process of the double-layer charge at a depth of 150 cm underwater is simulated by LS-DYNA. This paper analyzes the load type, shock wave pressure characteristics and propagation behavior of the double-layer charge during underwater explosion. By analyzing the impact of the shock wave pressure in the water under different charge intervals and time intervals on the shock wave pressure of the double charge, it is concluded that the peak pressure of the double charge explosion shock wave is jointly determined by the double charge. In this range, the second peak pressure value of the drug is greater than the pressure value of the first peak of the drug, and the attenuation is slow; the delay time of the upper charge has little effect on the peak pressure value of the shock wave in the water; the delay time is higher than that of the lower charge Initiation, at the same position, the total pressure peak of the shock wave formed by the delay of the upper charge is larger.

The purpose of the research is to assess the sound absorption performance (SAP) of acoustic metamaterials made of double-layer Nomex honeycomb structures in which a micro-orifice corresponds to a honeycomb unit. For this purpose, the influences of structural parameters on the SAP of acoustic metamaterials were investigated by using experimental testing and a validated theoretical model. In addition, the sandwich structure was optimized by the genetic algorithm. The research shows that the panel thickness and micro-orifice diameter mainly affect the second resonant frequency and second peak sound absorption coefficient (SAC) of the structure. The unit cell size is found to influence the first and second resonant frequencies and two peaks of the SAC. An extremely low side-length of the honeycomb core decreases the SAP of the structure for low-frequency noise signals. Additionally, the sandwich structure presents a better SAP when the diameter of micro-orifices on the front micro-perforated panel (MPP) exceeds that of the back MPP. The sandwich structure shows better noise reduction performance after the optimization aiming at the noise frequency outside trains.

A genetic algorithm was employed as a novel method to determine the best combination of materials for a double-layer electromagnetic shielding composite with good electromagnetic wave absorption efficiency at high frequencies from numerous magnetic materials. A carbonyl iron soft magnetic composite and a flaky FeNi soft magnetic composite were used to form the double-layer composite. The reflection and transmission parameters of the double-layer composite were measured using a vector network analyzer. The electromagnetic shielding effectiveness (SE) of the double-layer composite was calculated and analyzed. The double-layer composite was composed of two shielding materials with different electromagnetic parameters and demonstrated an excellent electromagnetic SE greater than 20 dB above 4 GHz; the ratio of the absorption efficiency (SEA) to SE (SEA/SE) was greater than 0.95, which indicates that more than 95% of the electromagnetic waves at high frequencies were attenuated by the shielding material, rather than being scattered into the surrounding environment. The double-layer composite exhibits excellent performance toward high electromagnetic waves absorption during the EMI shielding process.

The micro-perforated panel (MPP) has only one sound absorption peak, and the sound absorption performance is poor in the wide frequency range. Besides, the stiffness and strength of MPP are insufficient, so it can not bear the external load. In this study, double layers of hierarchical square honeycomb are placed within the air-back cavity of MPP to produce a sandwich structure. On the one hand, hierarchical honeycombs divide the air-back cavity into several sub-cavities. The perforations on the panel together with the sub-cavities form a series-parallel system of Helmholtz resonators. The sound absorption curve of the structure has multiple peaks and the half-absorption bandwidth is extensively widened. On the other hand, the hierarchical honeycomb with excellent load-bearing properties can strongly support the MPP to resist external loads. This new structure possesses both sound absorption and load bearing capabilities, and has practical application value in the noise reduction of high-speed trains and civil aircraft. Through theoretical and simulation analysis, the sound absorption performance of the structure is systematically studied and the influence of key parameters is quantified, providing guidance for the design of noise reduction materials.

Comparative studies are performed on the fundamental characteristics of charging classical dielectrics (PMMA) and ferroelectrics (LiNbO3) upon ion irradiation. Samples in experiments are irradiated with Ar+ ions having energies of 5–10 keV. General patterns are revealed in the kinetics of charging and typical differences in the characteristics of the current of the emitted ions, the displacement current (charge accumulation), and the surface potential. The first characteristic feature of charging ferroelectrics is the emergence of additional current in the detecting devices (the current of repolarization). The second feature is the presence of a double layer of charges on the surfaces of ferroelectrics. This double layer affects all kinetic characteristics of charging.

BACKGROUND Intestinal anastomosis is an operative procedure that is of importance in the practice of surgery. It is a very commonly performed technique in today’s surgical era. We wanted to study the postoperative complications like anastomotic leak and abscess formation and duration of hospital stay in single layer and double layer anastomosis and compare the same. METHODS In our prospective observational study, 80 patients were reviewed and were divided into 2 groups. Cases were allotted to either group based on the odd even method requiring single- and double-layer anastomosis, odd being single layer and even being double layer anastomosis. Intestinal anastomosis was carried out in single layer technique with delayed absorbable suture material and double layer technique with inner transmural layer with delayed absorbable suture material and seromuscular layer with non-absorbable suture material. RESULTS Each group had 40 patients, there was significant difference noted between the groups. Mean duration of hospital stay in single layer group was 17.85 ± 7.62 days and in double layer group was 26.20 ± 16.12 days (P = 0.043 *). In single group, mean time taken for anastomosis was 18.50 ± 1.73 and in double group was 29.05 ± 2.19. There was significant difference in time taken between two groups (P < 0.001). In single group, majority of subjects had no anastomotic Leak (95 %) and 5 % had leak. In double group 70 % had no leak and 30 % had leak. P value was statistically significant (P = 0.037). CONCLUSIONS Single layer anastomosis was better in terms of duration of hospital stay, postoperative anastomotic leaks and time taken for anastomosis. KEY WORDS Single Layer, Double Layer, Small Bowel, Duration of Hospital Stay, Anastomotic Leaks

In the present study a double layer mucoadhesive buccal film containing nanocarriers encapsulated with neem extract was fabricated through electrospinning and solvent casting techniques for dental therapeutic applications. The morphological, physical and mucoadhesive properties of the resulting electrospun and solvent cast oral films were mutually compared, and their drug release behavior and antibacterial activity were further investigated. Chitosan/poly(vinylalcohol) (PVA) as a mucoadhesive component and phenylalanine amino acid nanotubes (PhNTs)-containing neem extract as a drug nanocarrier were used to fabricate oral films. A poly(caprolactone) (PCL) layer was used as an impermeable backing layer to protect the mucoadhesive component from tongue movement and drug loss. The results indicated an interconnected porous and fully filled solid structures for electrospun and solvent cast films, respectively. The physicomechanical parameters of the samples such as pH, weight, thickness, folding endurance and tensile strength were also evaluated. The crosslinked electrospun buccal film indicated better swelling and mucoadhesive properties compared to the solvent cast film. In addition, the drug loading capacity and encapsulation efficiency of the solvent cast film showed lower experimental values than those of electrospun oral film. On the other hand, the electrospun oral film had a well-controlled release of neem extract up to 82% at oral pH, which is best fitted to the Weibull model, and demonstrated the highest antibacterial properties against S. mutans bacteria with high biocompatibility on L929 fibroblast cells. Generally, the synthesized electrospun mucoadhesive film has a better potential for oral therapeutic applications than the solvent cast film.

The effect of double-layer nanoparticles (DNPs) on vascular restenosis was investigated in this study, which were prepared by combining vascular endothelial growth factor (VEGF) and paclitaxel (PTX). Different blank NPs (Blank), VEGF NPs, PTX-NPs single-layer NPs (PTX-NPs), and DNPs were prepared with VEGF, PTX, polylactic-polyglycolic acid (PLGA), and polyvinyl alcohol (PVA), so as to analyze the cytotoxicity of NPs. Besides, different NPs were compared in terms of the characterization, encapsulation efficiency (EE), in vitro release (IVR), and cell proliferation inhibition ability. 30 adult New Zealand white rabbits were selected to construct a balloon injury model (BIM). Then, they were divided into 5 groups according to different treatment NPs, including a model group (BIM), a Blank group (BIM + Blank NPs); a PTX-NP group (BIM + PTX-NPs), a VEGF-NPs group (BIM + VEGF-NPs), and DNPs group (BIM + DNPs), with 6 rabbits in each group. There was a comparison on the histology, arterial stenosis, hyperplasia index (HI), and intimal thickness (IT) of arterial vessels from different groups, and immunohistochemistry was employed to analyze the changes of VEGF and C-reactive protein (CRP) protein expression levels in arterial tissues of different groups. The results showed that the cell survival rate (SR) was 88.69 ±3.17% and 90.64 ± 1.86% in turn when PLGA and PVA were both 100 ¿tg/mL. The polydispersity index (PDI), minimal Zeta potential (ZP), and average particle size (APS) of DNPs were 0.16 ±0.02, -8.45 ±0.07, and 242.26 ±2.58 nm, respectively. The drug loading (DL) of PTX and plasmid VEGF 165 in DNPs were 29.33% and 4.93%, respectively. The release of PTX from DNPs on the 30th day was close to 50%, and the cumulative release of deoxyribonucleic acid (DNA) was close to 75%. There was no obvious difference in the cell SR within 7 days after DNPs were added into Chinese Hamster ovary (CHO) cells and vascular smooth muscle cells (VSMC) compared with the control group (P > 0.05). The arterial stenosis, HI, and IT of the DNPs group were greatly lower than those of the model group (P < 0.05). The expression of VEGF protein in arterial tissues of DNPs group was higher in contrast to the model group (P < 0.01), while the expression of CRP protein was lower than that of the model group (P < 0.05). It showed that the DNPs combined with VEGF and paclitaxel administered by balloon infusion could obviously inhibit the vascular restenosis by increasing the expression of VEGF and reducing the expression of CRP, which provided a reference for the clinical prevention and treatment of postoperative vascular restenosis.

External control of chemical processes is a subject of widespread interest in chemical research, including control of electrocatalytic processes with significant promise in energy research. The electrochemical double-layer is the nanoscale region next to the electrode/electrolyte interface where chemical reactions typically occur. Understanding the effects of electric fields within the electrochemical double layer requires a combination of synthesis, electrochemistry, spectroscopy, and theory. In particular, vibrational sum frequency generation (VSFG) spectroscopy is a powerful technique to probe the response of molecular catalysts at the electrode interface under bias. Fundamental understanding can be obtained via synthetic tuning of the adsorbed molecular catalysts on the electrode surface and by combining experimental VSFG data with theoretical modelling of the Stark shift response. The resulting insights at the molecular level are particularly valuable for the development of new methodologies to control and characterize catalysts confined to electrode surfaces. This Perspective article is focused on how systematic modifications of molecules anchored to surfaces report information concerning the geometric, energetic, and electronic parameters of catalysts under bias attached to electrode surfaces., Heterogeneous electrocatalysis: characterization of interfacial electric field within the electrochemical double layer.

Fiber dispersion was one of the crucial factors, which influenced the mechanical properties of fiber reinforced metal matrix composites (FR-MMCs). The incomprehension of fiber dispersion mechanisms and the lack of control methods limited the developments and further applications of the 3D printed FR-MMCs. In this work, the tensile properties and microstructures of continuous carbon fiber reinforced SnPb matrix composites, which were fabricated by the double-layer printing head 3D printing process (DPP), were measured and observed. The dual mechanisms of capillarity pressure driving and nonuniform interface reaction driving in fiber dispersion were proposed. Besides, the dynamic of fiber dispersion was discussed. It was found that improving wicking performance could increase the dispersion of fibers. This research filled in the blank of fiber dispersion mechanisms of 3D printed FR-MMCs, and provided the methodological supports for further improving the performances of composites.

Generation of homozygous double haploid (DH) lines by androgenesis is a promising alternative to selfpollination programs across generations. Despite the routine use of anther culture in peppers, there are still many bottlenecks and improvements in methodology are required. The aim of this study was to determine the effects of the structure of the nutrient medium (semi-solid and double layer) and the addition of biotin and ascorbic acid to the nutrient media on obtaining haploid embryos by anther culture method. MS (Murashige and Skoog 1962) medium containing 4 mg l-1 NAA, 0.1 mg l-1 BAP, 0.25% activated charcoal, 30 g l-1 sucrose, and 10 mg l-1 AgNO3 (silver nitrate) were used as the basal nutrient medium. A total of 8 nutrient media compounds were studied using 0.05 mg l-1 biotin and 0.5 mg l-1 ascorbic acid separately or together in semi-solid and bi-layer (double-phase) nutrient media. Solidification of nutrient media was achieved with 7 g 1-1 agar. The cultured anthers were subjected to high-temperature pre-treatments at 35 °C in continuous dark conditions for 2 days. Then they were taken to a climate chamber at of 25 °C temperature adjusted to 16/8 hour photoperiod. It has been observed that the success of obtaining embryos of semi-solid medium was higher than double-layer medium. The addition of biotin and ascorbic acid to the nutrient medium provided 8.8 fold increases in embryo regeneration compared to the control medium. In the presence of only one of biotin or ascorbic acid in the nutrient medium, the number of embryos increased compared to the control.

The radiation of a double‐layer spherical dielectric lens equipped with a conformal spherical‐disk PEC reflector and excited by elementary sources located on the antenna axis of rotation is considered. The sources are either a radial electric dipole or a tangential magnetic dipole. Using the analytical inversion of the static part of the homogeneous‐lens problem with the aid of the Abel integral transform, developed earlier for plane‐wave scattering, each of the considered problems are cast to the Fredholm second‐kind infinite matrix equation with elements containing only the elementary functions. This guarantees convergence and enables accurate characterisation of the considered lens antennas in terms of directivity and total radiated power, in wide frequency range. It is demonstrated that the best directivity is provided by the quasi‐Luneburg lens configuration with dielectric constants of the core and the shell being 2 and 1.1, respectively, shell thickness being 0.1 of the outer lens radius, and reflector size around 30°. This performance, however, is spoiled by the whispering‐gallery‐mode resonances that can be effectively alleviated by the introduction of the moderate losses to the shell material.

In this paper, we propose a new intelligent temperature-controlled ventilated double-layer Trombe wall system for cold climate zones. This system consists of an insulation layer, an inner air chann...

The application of electrochemical potentials to surfaces is an easy and direct way to alter surface charge density, the structure of the electrochemical double layer, and the presence of electrochemically activated species. On such electrified interfaces the formation of biofilms is reduced. Here we investigate how applied potentials alter the colonization of surfaces by the marine bacterium Cobetia marina and the marine diatom Navicula perminuta. Different constant potentials between -0.8 and 0.6 V as well as regular switching between two potentials were investigated, and their influence on the attachment of the two biofilm-forming microorganisms on gold-coated working electrodes was quantified. Reduced bacteria and diatom attachment were found when negative potentials and alternating potentials were applied. The results are discussed on the basis of the electrochemical processes occurring at the working electrode in artificial seawater as revealed by cyclic voltammetry.

Thin-walled tubes are widely used as energy absorption devices because of their excellent crashworthiness. In this paper, a novel tubular configuration with a double-layer sinusoidal corrugated sec...

Heat gain through glazing is a major source of the space cooling load in subtropical cooling-dominant climates. Application of energy-efficient glazing systems can significantly reduce the energy consumption of air conditioning in summer. Thus, it has become a popular research topic. In this study, a sample of silica aerogel glazing was developed and prepared. Two identical insulated boxes were then constructed; one faÇade was equipped with the aerogel glazing sample and the other was prepared with a conventional double-layer glazing. An onsite measurement of the boxes’ internal thermal properties was then conducted. The two boxes were placed within the same outdoor environment. The temperature, humidity, and enthalpy values were calculated with the boxes facing different orientations and in a variety of weather conditions. The performance of the silica aerogel glazing was then evaluated by both experimental and theoretical analysis. The results of this study will provide a basis for aerogel glass building application guidelines.

The ion distribution and its dynamic at the interface between solid and liquid play the main role in many applications. Measuring the solution at the solid–liquid interface in situ and noninvasively has been challenging because the electrolyte solution is volatile. Traditional ion beam analysis suffers from the energy straggling caused by the thick window and high-resolution analysis requires in-vacuum measurement. In this work, a cell with a 25 nm thick entrance window was fabricated. Solution of 0.1 mol/l BaCl2 was measured with 2 MeV He+ at the solid-electrolyte interface. It was revealed that a double layer structure was observed from the RBS spectrum. After measuring the cell for 4 h, there was no visible damage to the window. Therefore, this method can be used to measure the electrolyte solution in a vacuum in situ. It can also be expanded to measure gas or other volatile samples.

This study reports that photodetectors based on double‐layer ZnO nanorods grown on AZO seed layer by hydrothermal method. Compared with the photodetectors with single‐layer nanorods, the on/off ratio of the photodetectors with double‐layer ZnO nanorods is increased by ∼2.52 times, the photoresponsivity is increased ∼5.50 times, the sensitivity is increased ∼3.34 times and the response time was shortened by 0.97 and 6.65 s, respectively. Furthermore, the photocurrent derivative also shows that the photodetectors based on double‐layer ZnO nanorods has a faster response speed.

This case report illustrates the successful use of the double-layer amniotic membrane technique in a child with glaucoma and aniridia. A 3.5-year-old girl with bilateral congenital glaucoma as well as aniridia, lens coloboma, nystagmus, and strabismus had been followed up since birth. Medical treatment did not result in the desired intraocular pressure improvement. An Ahmed glaucoma valve was implanted bilaterally. In a follow-up visit at 2 years of age, there were complaints of redness with watery discharge in the right eye. A biomicroscopic evaluation revealed tube erosion of the conjunctiva. The eroded area was dissected from the surrounding tissue and the area was closed using the new double-layer amnion membrane technique. After the surgery, the intraocular pressure was normal. Subsequent follow-up indicated that the erosion defect was closed and stabilized. The double-layer amniotic membrane technique can be used successfully in cases of conjunctival tube erosion. To the authors' knowledge, this is the first published pediatric case report of using the novel technique of amniotic membrane transplantation for tube erosion.

In the approximation of a thin double layer, simple dependences of the acoustic fields excited in an electrokinetic electroacoustic transducer on the velocity of the Helmholtz—Smolukhovsky osmotic movement are obtained. From the dependencies it follows that in the absence of losses, when the nonlinearity of the fluid motion equation does not yet affect and there is no turbulent mode of fluid motion in the transducer body, the magnitudes of the amplitudes of the acoustic velocity and pressure linearly depend on the magnitude of the Helmholtz—Smolukhovsky electroosmotic motion velocity.

Magnesium alloys have found widespread application as engineering and functional materials in automobile, aerospace, electronics, and biomedical industries. However, these alloys are susceptible to corrosion, and the development of new anticorrosion coatings on Mg alloys surface is urgently needed. In this work, pristine and doped double-layer silane coatings were applied to the AZ91D Mg alloy surface in order to improve its corrosion resistance properties in a 3.5% NaCl solution. The doped silane coatings consisted of KH-550 as the bottom layer and Nd(NO3)3-doped bis-(γ-triethoxysilylpropyl)-tetrasulfide (BTESPT) as the top layer. The effect of Nd(NO3)3 concentration on the corrosion inhibition properties of silane coatings was studied, and the highest corrosion resistance was achieved when the Nd(NO3)3 concentration was 5 × 10−3 mol/L. Compared to the pristine coating, the doped coating had enhanced hydrophobicity with a water contact angle of 108° and, to the best of our knowledge, one of the lowest corrosion current densities (1.51 × 10−2 μA/cm2) reported to date for treated AZ91D. These significant improvements were attributed to the presence of the Si-O-Nd network in the doped coating, leading to the uniform and homogeneous nature and excellent anticorrosion properties of Nd-doped silane coating.

The FeZnO (iron zinc bimetallic oxide) was synthesised using the ultrasound-assisted method and further converted into FeZnOAC (iron zinc bimetallic oxide-doped activated carbon) by treating it with activated carbon. As developed FeZnOAC is effectively used for the adsorption of Fuchsine dye from an aqueous dye solution. A 200 mg of FeZnOAC was sufficient for the rapid removal of Fuchsine (>97.64%) dye. The kinetic adsorption data is well fitted with a pseudo-second-order model. The Langmuir isothermal model shows a high regression coefficient (R2) than the Freundlich with a Qmax of 333.33 mg g−1. The dye adsorption at varying temperatures (i.e. 298–318 K) was based on a multi-layered statistical physics model. The n value (n