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We propose a new way of deriving the effective thickness in attenuated total reflection (ATR) spectroscopy, initially introduced by Hansen and Harrick in 1965. While following Hansen's approach, our derivation is more straightforward and includes an intermediate approximation that more closely aligns with results derived from Fresnel's equations, particularly for organic and biological materials. Using this intermediate approximation, we present improved estimations for the effective thicknesses with s- and p-polarized light. These estimations enabled us to enhance a recently developed ATR correction scheme that relies on effective thickness. Additionally, we examined the wavelength dependence of the product of wavenumber and effective thickness, observing that it bears a resemblance to the refractive index function of the sample. This similarity increases with the angle of incidence and the refractive index of the ATR crystal. Based on this observation, we introduce a simple correction scheme using the Kramers–Kronig transformed absorbance. This correction has the potential to address spectral shifts, facilitating applications in pattern recognition and spectra identification. [ABSTRACT FROM AUTHOR]

We present an attenuated total reflection (ATR) correction scheme capable of rectifying ATR spectra while considering the polarization state for arbitrary angles of incidence, provided that this angle exceeds the critical angle for the entire ATR spectrum. Due to its reliance on the weak absorption approximation, it cannot achieve perfect correction of the ATR spectra. However, comprehending its functionality may offer valuable insights into the concept behind the weak absorption approximation. Depending on the specific polarization state of an instrument accessory combination, this correction scheme may outperform the proprietary advanced ATR correction authored by ThermoFisher while being as user-friendly, but in contrast to the latter completely transparent with regard to its functionality. [ABSTRACT FROM AUTHOR]

This paper investigates the role of the adequate thickness of the Asmari reservoir formation zones on oil production in one of the Iranian carbonate oil fields. Adequate thickness is a term that includes the total gross thickness of rocks by lithofacies for a selected wellbore. The lithology of the Asmari formation in the studied area consists of dolomite, sandstone, lime, dolomitic-lime, sandstone-shale, and shale limestone dolomites. Based on the existing well-logs, the average shale volume, the effective arithmetic means of porosity in the gross intervals, and average water saturation or hydrocarbon-bearing increments of the studied field are calculated using well-logs. In wellbore #A, a depth interval of 2214 to 2296 m shows 9.6% average shale volume, 27.2% average water saturation, and 20.9% average porosity. A depth interval of 2213 to 2280 m, in wellbore #B, shows 6% average shale volume, 21.25% average water saturation, and 28.5% average porosity. Based on our petrophysical assessments, we divide the Asmari reservoir in the studied field into eight zones. Zone 1 is made of carbonate (calcareous and dolomitic), and zones 2-5 are mainly sandstone; zones 7 and 8 are calcareous and shale, and zone 6 is a mixture of all the rocks mentioned above. Among these eight zones, there are two primary hydrocarbon productive zones. The numerical calculation of in situ oil volume showed that zone 2 contains 65% of oil volume in this reservoir. With more than 80% sand, this zone has the highest net hydrocarbon column. [ABSTRACT FROM AUTHOR]

Abstract In the last years, the effective thickness concept has been used to calculate deflections, stresses and modal parameters in laminated glass beams and plates, which consists of using a monolithic element with equivalent bending properties to a laminated element, i.e. the thickness of the equivalent monolithic model is time and temperature dependent because the interlayers show a viscoelastic behavior. Multi-layered laminated glass panels are those with at least three monolithic glass layers and two viscoelastic interlayers which are commonly used in floors, roofs and other applications where a high level of security is required. In this paper, a static deflection effective stiffness for a laminated glass plate consisting of three glass layers and two polymeric interlayers is derived. This static effective thickness is then extended to the frequency domain using the correspondence principle. The models are validated by static experimental tests and operational modal tests carried out on a rectangular multi-layered laminated glass plate pinned supported at the four corners. [ABSTRACT FROM AUTHOR]

In this work, a biosensing method based on in situ, fast, and sensitive measurements of ellipsometric parameters (Ψ, Δ) is proposed. Bare silicon wafer substrate is functionalized and used to bind biomolecules in the solution. Coupled with a 45° dual-drive symmetric photoelastic modulator-based ellipsometry, the parameters Ψ and Δ of biolayer arising due to biomolecular interactions are determined directly, and the refractive index (RI) of the solution and the effective thickness and surface mass density of the biolayer for various interaction time can be further monitored simultaneously. To illustrate the performance of the biosensing method, immunosensing for immunoglobulin G (IgG) was taken as a case study. The experiment results show that the biosensor response of the limit of detection for IgG is 15 ng/mL, and the data collection time is in milliseconds. Moreover, the method demonstrates a good specificity. Such technique is a promising candidate in developing a novel sensor which can realize fast and sensitive, label-free, easy operation, and cost-effective biosensing. [ABSTRACT FROM AUTHOR]

Polyamide composites are instrumental to modern desalination technology; however, reasons for the superior performance of polyamide membranes have been unclear. Models usually view membranes as an array of charged nanopores, however, observed discrepancies and inconsistencies call for more insights. Here ion conductance in polyamide membranes was analyzed using electrochemical impedance spectroscopy, focusing on the effects of salt type, concentration, and pH, which are compared with the conductance obtained for a dense linear polyamide Nomex® of similar superficial thickness. The results rule out the common view of polyamide membranes as homogeneous layers or nanopore arrays and indicate that they essentially behave as thin films of Nomex. The salt exclusion in both materials is so strong that uptake of protons (rather than sodium) dominates membrane conductivity, yielding a similar concentration-dependence. However, the conductivity of polyamide membranes is much higher and equivalent to sub-10 nm Nomex films. These findings are explained by the sponge-like structure of polyamide, containing voids separated by thin polymer films, which can be adequately modeled as a 3D random resistor network. This unique structure, combining very dense (hence highly selective) and extremely thin (hence reasonably permeable) films supported within a ~100 nm porous layer is what enables exceptional performance of polyamide membranes. [ABSTRACT FROM AUTHOR]

A film measuring method based on a new data model using a home-made microscopic white light spectral interferometer is proposed. It can improve the measuring accuracy of the thin film thickness at different OPDs. The influence of the effective thickness caused by the beam splitter prism in a Michelson interferometric objective is analysed and found not to be negligible while calculating the thin-film thickness. The linear relationship between the effective thickness and the optical path difference (OPD) can be removed by introducing a wavelength correction which made the effective thickness measurement more accurate. Some experiments on the film standard with calibrated film thickness showed that introducing a wavelength correction made the film thickness measurement more accurate at different OPDs. [ABSTRACT FROM AUTHOR]

The cross-sectional behaviour of laminated glass (LG) is characterised by a significant zigzag effect owing to the large stiffness mismatch between the glass and polymer layers. The approach incorporated in current glass design standards is based on the use of a monolithic model with an effective thickness, which suffers several sources of inaccuracy and limitations. In this paper, laminated shell elements with an alternating stiff/soft lay-up are enhanced and used to model LG structures, so as to accurately reproduce the through-thickness behaviour of LG with a minimal number of zigzag displacement parameters per node. In order to consider the influence of loading rate and temperature on the response of LG, a linear viscoelastic material model is adopted to simulate the polymer interlayer, which is formulated based on a recursive formula for stress calculation. Finally, several applications of the proposed modelling approach for two-ply and multi-ply LG structures are presented, considering typical deflection, stability and creep problems, where the benefits of the proposed approach are demonstrated through comparisons against monolithic shell models based on an effective thickness as well as 3D continuum models. [ABSTRACT FROM AUTHOR]

We present the results of experimental studies of the dependence of the diffraction efficiency of nonoblique transmission holograms formed in the sample of a (īī0)-cut photorefractive piezoelectric Bi1SiO crystal on the sample thickness and orientation angle of the grating vector at two fixed mutually orthogonal orientations of the linear polarization vector of the reading beam. It is shown that only if along with optical activity of the crystal, the electrooptic, inverse piezoelectric, and photoelastic effects are taken into account in the analytical diffraction model, it is possible to carry out satisfactory theoretical interpretation of the experimental data. [ABSTRACT FROM AUTHOR]

In this contribution, we examine the mechanical behavior of laminated glass fabricated with relatively thin (<2 mm) glass components. It is shown that optimum light weight laminates are best achieved through the use of a relatively stiff, ionomer interlayer versus a traditional rubbery, poly-vinyl butyral (PVB) interlayer. We present results of bending experiments in which laminate deflection and glass stress development have been monitored as a function of load for various laminate structures. Interpretation of laminate mechanics using effective thickness theories is demonstrated. We present a formulation for computing the optimum specific stiffness and strength of a laminate for given loading/support conditions and establish theoretical limits to weight reduction for a defined monolithic glass performance target. [ABSTRACT FROM AUTHOR]

We introduce a simulation technique suitable to model the tunneling leakage current in the metal(polySi)/CaF 2 /Si(111) MIS structures using TCAD simulators Minimos-NT and ViennaSHE. The simulations are performed using the real physical parameters of the CaF 2 /Si tunnel barrier. The results obtained for the case of near-equilibrium carrier transport are in a good agreement with experimental data and also with the simulation results yielded by our reference physical model. The obtained non-equilibrium hot-electron tunnel leakages in the hypothetical transistors with CaF 2 as a gate dielectric are comparable to those in the structures with silicon dioxide. Being an important step forward for the device application of calcium fluorite, this work opens the possibility of simulating the characteristics of different silicon-based systems with crystalline insulators. [ABSTRACT FROM AUTHOR]

A practical, nondestructive method to determine the shear relaxation modulus behavior of viscoelastic polymer interlayers used in laminated glass is demonstrated. The method is based on a direct measurement of the laminate effective thickness using a four point bend test geometry or uniform pressure loading of laminate plates. The effective thickness expressions that incorporate the polymer shear modulus explicitly in the formulation are then used to calculate the polymer shear modulus in an inverse fashion. Comparison of this approach with dynamic mechanical analysis shows the new approach to be accurate over a wide range of test conditions. The approach described has the advantage of being able to characterize the polymer interlayer in situ. We have focused on laminated glass in this study, but the approach is applicable to any laminated combination of different material types consisting of a compliant core sandwiched between stiff skins. [ABSTRACT FROM AUTHOR]

For complicated structural components characterized by wide X-ray attenuation ranges, the conventional fixed-energy imaging mode cannot obtain all structural information using a single tube voltage. This limitation results in information shortage, because the effective thickness of components along the orientation of the X-ray penetration exceeds the limit of the dynamic range of the X-ray imaging system. To solve this problem, multi-energy image sequence fusion technology has been advanced. In this new method, the tube voltage is adjusted several times by matching the voltage and the effective thickness to obtain all the effective local information on an object. Then, the subset sequences in the multi-energy image sequence are extracted based on the recursive template, and that are fused to reconstruct the full projection information based on linear weighting. An accompanying experiment demonstrates that the new technology can extend the dynamic range of X-ray imaging and provide a complete representation of the internal structure of complicated structural components. [ABSTRACT FROM AUTHOR]

The effectiveness of polypropylene fibers as sorbents of oil-water emulsions was the object of the research in the present publication. Thus the sorption capacity of the synthetic material of the regional production with for emulsions of different concentration was investigated. [ABSTRACT FROM AUTHOR]

Abstract: In conventional X-ray imaging, the ray image of a complicated structural component (complex in shape or structure or composed of multiple materials) often appears to be overexposed or underexposed. This appearance is because of the variations in the effective thickness of the component along the orientation of the X-ray penetration exceed the limit of the dynamic range of the X-ray imaging system. Complete structural information cannot be obtained, and this lack will impact the quality of the X-ray image. To solve this problem, the technology of multi-voltage image stack reconstruction has been advanced. In this new method, the tube voltage is adjusted several times to accommodate the full necessary range of effective thickness, and then, the extracted images are fused to reconstruct the full projection information. The new technology can adequately enlarge the hardware potential to completely represent the internal structure information of a complicated structural component. [Copyright &y& Elsevier]

Abstract: Superhydrophobic coatings possess a strong water-repellent characteristic, which, among several other potential applications, enhances the mobility of water droplets over the surface. The coating traps air within its micropores, such that a submerged moving body experiences shear-free and no-slip regions over, respectively, the air pockets and the solid surface. This, in turn, may lead to significant skin-friction reduction. The coating maintains its superhydrophobicity as long as the air remains entrapped. It is therefore of great interest to precisely measure the amount of trapped air, which is particularly difficult to estimate for coatings with disordered microstructures. A novel method to measure the effective thickness and gas volume fraction of superhydrophobic coatings with either ordered or random microroughness is advanced. The technique is applied to both aerogel and electrospun fibrous coatings. The experiments utilize a sensitive weighing scale (down to 10−4 gm) and height gauge (down to 10μm) to determine the buoyancy force on an immersed, coated glass-slide substrate. The measured force is used to calculate the volume fraction of entrapped air. The coating’s effective thickness also follows from the same calculations. The sensitivity of our particular scale enables the measuring of thicknesses down to 3μm, which is not readily possible with conventional thickness gauges. Smaller thicknesses could be measured using more sensitive scales. [Copyright &y& Elsevier]

A precise evaluation of the active reaction zone in the electrodes is important to design an effective solid oxide fuel cell (SOFC). A scale analysis and one-dimensional numerical simulations are conducted to obtain a better understanding of the electrochemical reaction zone in a SOFC anode. In the scale analysis, the characteristic lengths of the electron, oxide ion, and gas transports are evaluated from their conservation equations. Relative comparisons of the characteristic lengths show that the transport phenomena in the SOFC anode are primarily governed by the oxide-ion conduction under standard operating conditions. The gas diffusion may affect the extent and the location of the active reaction zone at high temperature and/or low reaction gas concentration conditions. The one-dimensional numerical simulations for an anode provided detailed information such as the electric potential of electron- and ion-conducting phases, the gas concentration, and local charge-transfer current distributions. It is found that the electrochemical reaction actively occurs in the vicinity of the anode-electrolyte interface. The effective thickness increases as the characteristic length of the ion conduction is increased resulting in better power generation performance. The effective thickness is also increased when the gas-diffusion length is short. The cell performance is, however, lowered in this case because the low gas diffusivity yields the increase of the ohmic loss of ion conduction as well as the concentration overpotential. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.20373 [ABSTRACT FROM AUTHOR]

Abstract: We report on a simple processing procedure to retrieve the phase from spectral interferograms including a stationary-phase point. First, the numerical simulations are performed to demonstrate high precision of the phase retrieval from the spectral interferogram. Second, the feasibility of the procedure is confirmed in processing the experimental data from a dispersive Michelson interferometer comprising a cube beam splitter and a plate made of BK7 optical glass. From the retrieved spectral phase, the effective thickness of the BK7 optical glass is determined precisely. [Copyright &y& Elsevier]

This paper presents the results of an investigation into the post-buckling behaviour and ultimate strength of imperfect pitted steel plates used in ship and other marine-related structures. A series of elastic-plastic large deflection finite element analyses is performed on pitted steel plates. The effects of pitting corrosion on one side of the plates are introduced into the finite element models. The effects on plate compressive strength as a result of parametric variation of the pitting corrosion geometry are evaluated. A proposal on the effective thickness is concluded in order to estimate the ultimate strength and explore the post-buckling behaviour of pitted steel plates under uniaxial compression. [ABSTRACT FROM AUTHOR]

Abstract: The performance of laminated glass, which consists of two or more glass plies bonded together by polymeric interlayers, depends upon shear coupling between the plies through the polymer. This is commonly considered by defining the effective thickness, i.e., the thickness of a monolithic beam with equivalent bending properties in terms of stress and deflection. General expressions have been proposed on the basis of simplified models by Newmark and Wölfel–Bennison, but they are either difficult to apply or inaccurate. Here, a variational approach to the problem is presented. By choosing appropriate shape functions for the laminated-beam deformation, minimization of the strain energy functional gives new expressions for the effective thickness under any constraint- and load-conditions, embracing the classical formulations as particular cases. Comparisons with numerical experiments confirm the better accuracy of the proposed approach with respect to the previous ones. [Copyright &y& Elsevier]

Two new asymmetric slab optical waveguides with a left-handed media (LHM) cover or substrate are studied. The effective thickness is derived by using normalized waveguide parameters. An analytical method is then proposed to calculate the universal effective thickness. We show that negative effective thickness exists in the waveguide with a LHM substrate, unlike in conventional waveguide or other LHM waveguides studied previously. However, for the waveguide with a LHM substrate, the shape of high-order mode behaves like that of a traditional slab waveguide, and neither the fundamental mode nor the other higher order modes have the novel phenomena of negative effective thickness. Both TE and TM modes are discussed. [ABSTRACT FROM AUTHOR]

It is natural to treat the monolayer crystalline film as the surface fixed by the positions of atoms. However, this type surface is not well-suited to the monolayer crystalline film. It has been discovered that the mechanical properties of a monolayer crystalline film can be described exquisitely by its inscribed surface. Depending on this inscribed surface of armchair carbon nanotubes, the present study shows the reason why CNTs cannot be simply considered as a thin shell with constant thickness. Application of the present model to armchair CNTs predicts that the ranges of Young's modulus and effective thickness are respectively from 2.407 to 3.209 TPa and from 0.082 to 0.073 nm, which are in good agreement with previous theoretical studies and experimental observations. [ABSTRACT FROM AUTHOR]

Abstract: This research investigates the possibility to use highly absorbing materials to dampen indoor RH% variations. The practical MBV of sodium polyacrylate, cellulose-based material, perlite and gypsum is evaluated for a daily cyclic exposure that alternates high (75%) and low (33%) RH% levels for 8h and 16h, respectively. The adjustment velocity to RH% variations and the presence of hysteretic phenomena are also presented. The cellulose-based material proves to be the most suitable for moisture buffering applications. Starting from this material’s properties, the effect of thickness, vapour resistance factor (μ) and mass surface exchange coefficient (Z v) on sorption capacity is evaluated by the use of a numerical model. [Copyright &y& Elsevier]

As the first step in discussing the reliability of composite structures, a fundamental study was performed to obtain the scattering characteristics of glass–fiber reinforced plastics (GFRP) and woven carbon fiber reinforced plastics (WCFRP) as well as a reference metal. The Euler buckling load was obtained experimentally for each material. The experiments were conducted for specified rectangular specimens with simply supported edges. A new attachment to realize the simply support boundary conditions for composite materials have been prepared before these experiments. The scattering data in the results for GFRP and WCFRP composites were compared with those of a typical metal of aluminum alloy. The experimental data were also compared with numerical simulations including the uncertainties. [ABSTRACT FROM AUTHOR]

Abstract: We report on processing the spectral interference signals by a new method based on a windowed Fourier transform applied in the wavelength domain. First, the numerical simulations are performed to demonstrate high precision of the phase retrieval from the spectral signal. Second, the feasibility of the method is confirmed in processing experimental data from a dispersive Michelson interferometer comprising a cube beamsplitter made of BK7 glass. From the retrieved spectral phase difference, the effective thickness of the beamsplitter is determined precisely. [Copyright &y& Elsevier]

Abstract: In this paper, the moisture buffering capacity of spruce plywood is measured by recording the change in mass of a test specimen when the air relative humidity is changed between 33% RH and 75% RH. The aim is to represent diurnal cycles in indoor humidity with 33% RH maintained for 16h and 75% RH maintained for 8h. Measurements are taken using two different apparatuses, which provide different convective transfer coefficients between the air and the plywood, and the results are compared to a numerical model for validation. The validated numerical model is then used to investigate the effect of initial conditions, boundary conditions and thickness on the moisture buffering capacity of plywood. The results show that the buffering capacity of plywood depends on the initial conditions and thickness of the plywood as well as the surface film coefficient and humidity cycle. [Copyright &y& Elsevier]

Microwave far-field radiation was simulated using a coax cable inside which a ferroelectric layer with a ground plane was loaded. The ferroelectric layer was electrically biased via a planar permeable electrode allowing an RF electromagnetic field to penetrate, thereby causing reflection. By interpolating the normal-mode frequencies of the cavity resonator formed by the coax cable, it was determined the coupling between the loaded ferroelectric sample and the resonator is second order. An effective electric-bias configuration for a ferroelectric layer is thus proposed. [ABSTRACT FROM AUTHOR]

Analyzing the experimentally evaluated self-attenuation correction coefficients needed in activity determination by means of gamma-ray spectrometry, the effective thicknesses of bulk samples of three shapes were evaluated. The effective thicknesses deduced significantly differ from the geometrical sample thicknesses in “close” measuring geometry. [Copyright &y& Elsevier]

• O impedance related to radial diffusion and restricted planar diffusion; for tip closely to hole surface-Cyclopore membrane. • Equivalent circuits including Cole-Cole diffusion impedance (Z M), Cole-Davidson type impedance (Z W) and O impedance (Z O) proposed for different separation distances. • Difference in diffusion impedance on hole and that on flat surface on Cyclopore membrane for estimating membrane thickness. A new, feasible, on-line method was proposed to determine Cyclopore polycarbonate membrane thickness by scanning electrochemical impedance microscopy (SEIM) technique. The thickness is 8.4 µm, which close to the report technical data. Three effective impedances for equivalent circuit model including Cole-Cole diffusion impedance, Cole-Davidson type impedance and O impedance were firstly proposed for radial diffusion and restricted planar diffusion mode when tip electrode on flat or hole surface in Cyclopore membrane. Data analysis results showed that restricted planar diffusion emerged when tip electrode approach tightly to hole surface. Additionally, SEIM responses on the flat and hole surface were compared and could be applied for topographic imaging in the future work. [ABSTRACT FROM AUTHOR]

Nanopores have been emerged as a powerful tool for analyzing the structural information and interactional properties of a range of biomolecules. The spatial resolution of nanopore is determined by the diameter and effective thickness of its constriction region, but the presence of vestibule or stem structure in protein-based nanopore could negatively affect the sensitivity of the nanopore when applied for genome sequencing and topological analysis of DNA. Recently, alpha-hederin (Ah) has been reported to form a sub-nanometer scale pore structure in lipid membrane. With the simple structure and extremely small effective thickness, the Ah nanopore was shown to discriminate four different types of nucleotides. However, identification of a certain nucleotide in a strand of DNA, which is essential for genome sequencing, remains challenging. Here, we investigated the resolving capability of Ah nanopore to discriminate few nucleotides in a strand of single-stranded DNA, and the factors determining the sensitivity of Ah nanopore. The Ah nanopore was shown to be able to identify as few as three adenosine nucleotides in a strand of poly cytidine, in which the dwell time of the additional current blockade that represents the adenosine residue was in good agreement with their physical length. We also found that the lateral tension and chain pressure generated around the nanopore were influenced by pore's diameter and played as a dependent variables to determine the geometry of nanopore's constriction as well as the spatial resolution of the Ah nanopore. Alpha hederin (Ah) nanopore was synthesized to discriminate the subtle structural difference of nucleotides in a strand of DNA, which is critical for nanopore-based topological analysis of DNA. The Ah nanopore was shown to have a resolving power of identifying as few as three adenosine nucleotides in a strand of poly cytidine. The geometry of pore's constriction region as well as the effective thickness of nanopore, which determine the spatial resolution of nanopore, were found to be regulated by the diameter of Ah nanopore. Image 1 • Identification of nucleotides in stranded form is of importance for genome sequencing. • Ah nanopore with small effective thickness was fabricated by molecular self-assembly. • Diameter-dependent lateral tension determines the spatial resolution of Ah nanopore. • Subtle structural difference between purine and pyrimidine could be discriminated. • Ah nanopore could identify the presence of three adenosines in a strand of poly-C. [ABSTRACT FROM AUTHOR]

Dual-layer hydrophilic-hydrophobic hollow fiber membrane is a promising membrane that simultaneously shows enhanced vapor transfer coefficient and inhibited conductive heat loss in direct contact membrane distillation (DCMD). The presence of an effective water-intrudable hydrophilic layer enables to reduce the vapor transportation distance and improve the water flux in DCMD. The aim of this study is to estimate the water-intrudable hydrophilic layer thickness in a dual-layer hydrophilic-hydrophobic hollow fiber membrane comprising a PVDF/PEG inner layer and a PVDF outer layer. The water-intrudable hydrophilic layer thickness was precisely measured by a dye solution permeation method under simulated DCMD conditions. The results showed that the water-intrudable hydrophilic layer thickness was highly determined by the pore size and effective porosity of the PVDF/PEG inner layer. The applied hydraulic pressure contributed significantly to the difference in the thickness of the water-intrudable hydrophilic layer. The membranes with higher thickness percentages of the water-intrudable hydrophilic layer exhibited simultaneously enhanced permeate water flux and energy efficiency in DCMD. This study offered a simple and reliable approach for the estimation of the effective thickness of the water-intrudable hydrophilic layer for the dual-layer hydrophilic-hydrophobic hollow fiber membrane that contributes substantially to the desalination performance enhancement in DCMD. Image 1 • Dual-layer hydrophilic-hydrophobic HF membrane was fabricated for DCMD. • The thickness of the water-intrudable hydrophilic layer (WIHL) was measured. • Both spinning and operating parameters affected the WIHL thickness. • The WIHL thickness highly determined DCMD performance. [ABSTRACT FROM AUTHOR]

• Brittle failure of timber connections should be considered in the design. • A new proposal to obtain the related timber element effective thickness is given. • This method is based on a beam on elastic foundation model. • The only considered parameter is the slenderness of the fastener. • The results improve both the accuracy and the simplicity of the existing methods. The consideration of brittle failure of timber connections requires an adequate evaluation of the capacity of the involved failure planes. Their correct geometrical definition is therefore of utmost importance to obtain an accurate assessment of their capacity. This article presents a new approach to account for the effective thickness of the lateral planes of timber members in connections with large diameter fasteners loaded parallel-to-grain when the fasteners remain in its elastic range, which allows to consider the uneven load distribution along the fastener in a simple way. The proposal is based on a fitting of a beam on elastic foundation model and only requires the slenderness of the fastener as a parameter. It provides a both simple and accurate way to calculate the effective thickness of timber elements. [ABSTRACT FROM AUTHOR]

• The torsional response of laminated rectangular panels is here analyzed. • The proposed analytical model applies also to multilaminated packages. • The model captures the transition from 1D beam- to 2D plate-geometries. • Simple formulae for the rotation- and stress-effective thickness are provided. • Comparisons with numerical experiments confirm the accuracy of the proposed model. The torsional response of laminated rectangular panes composed by N glass plies of arbitrary thickness, coupled by N - 1 polymeric interlayers, is here analyzed. Under the quasi-elastic approximation, that considers the secant stiffness of the polymer, we use the classical hypothesis that the all glass plies rotate of the same angle of twist to derive the shape function for the strain field, whose actual form is found by energy minimization. When the width of the pane is much less that its length, we find formulae that apply to the geometry of a beam, representing the counterpart for laminates of the solution à la de Saint Venant for elements with thin rectangular cross sections. This approach extends to the case of torsion the Enhanced Effective Thickness (EET) method, already proposed for bending, and generalizes other previously proposed engineering methods, which are only applicable for beams composed of a limited number of glass plies. Comparison with numerical results for different geometries confirms the accuracy of the proposed formulation. This method can be conveniently applied for the preliminary design of cold-bent laminated cells for façades, as well as to study the lateral torsional buckling of in-plane-bent beams. [ABSTRACT FROM AUTHOR]

Thickness is not a well-defined quantity for two-dimensional (2D) materials. Hence, there are several choices adopted widely to assign the thickness of a 2D nanosheet: (a) the interlayer distance in layered bulk crystals; (b) the vertical distance between outmost atoms; (c) the value of (b) plus atomic van der Waals radius. Except these definitions of thickness, we determine the effective thickness of 2D pnictogen nanosheets based on continuum elastic theory combined with first principle calculations, from which the tension rigidities are extracted by fitting the strain energies of biaxially stretched samples with a quadratic relation on the lateral and transversal strains for blue phosphorene, arsenene, and antimonene. Whereas the bending rigidities are computed from the pnictogen nanotubes rolled from flat 2D nanosheets. Given the tension and bending rigidities, the effective thickness could be determined from the ratio between these two quantities. Our results indicate that the effective thickness, being much smaller than the widely used interlayer distance in the corresponding bulk material, is suited to describe mechanical properties of 2D nanosheets in a consistent way. [ABSTRACT FROM AUTHOR]