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An impurity-free Pb(Fe 1/2 Nb 1/2)O 3 (PFN) ceramic was prepared using a conventional solid-state reaction method with precisely controlled sintering temperature. The PFN ceramic exhibits monoclinic symmetry and shows a dense morphology with equiaxed grains of about 1–2 μm. It exhibits a diffused phase transition at approximately 381 K. From the data of dielectric loss tangent and the imaginary parts of impedance and electrical modulus, a non-Debye type dielectric relaxation was investigated, and it was found that the short-range hopping of oxygen vacancies contributes to the dielectric relaxation and the relaxation time distribution is temperature independent. The PFN ceramic exhibits slim ferroelectric hysteresis loops and a linear magnetic hysteresis loop, indicating that the PFN ceramic is paramagnetic; the band gap is estimated to be 2.04 eV. Photoconductivity and photovoltaic responses with a nonzero open-circuit voltage and short-circuit photocurrent were detected. Moreover, magnetoconductivity was measured. This work implies that the PFN ceramic is a potential candidate for magnetoelectric and photovoltaic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Methods for adaptation projections are varied, with no consistent method established. • Many methods of including adaptation in projections are not based on evidence. • Including adaptation in projections considerably influences estimated mortality. • Combination or framework methods have been developed in more recent years. • Adaptation uncertainty should be included in future health impact assessments. Exposure to high and low ambient temperatures can cause harm to human health. Due to global warming, heat-related health effects are likely to increase substantially in future unless populations adapt to living in a warmer world. Adaptation to temperature may occur through physiological acclimatisation, behavioural mechanisms, and planned adaptation. A fundamental step in informing responses to climate change is understanding how adaptation can be appropriately accounted for when estimating future health burdens. Previous studies modelling adaptation have used a variety of methods, and it is often unclear how underlying assumptions of adaptation are made and if they are based on evidence. Consequently, the most appropriate way to quantitatively model adaptation in projections of health impacts is currently unknown. With increasing interest from decisionmakers around implementation of adaptation strategies, it is important to consider the role of adaptation in anticipating future health burdens of climate change. To address this, a literature review using systematic scoping methods was conducted to document the quantitative methods employed by studies projecting future temperature-related health impacts under climate change that also consider adaptation. Approaches employed in studies were coded into methodological categories. Categories were discussed and refined between reviewers during synthesis. Fifty-nine studies were included and grouped into eight methodological categories. Methods of including adaptation in projections have changed over time with more recent studies using a combination of approaches or modelling adaptation based on specific adaptation strategies or socioeconomic conditions. The most common approaches to model adaptation are heat threshold shifts and reductions in the exposure–response slope. Just under 20% of studies were identified as using an intervention-based empirical basis for statistical assumptions. Including adaptation in projections considerably reduced the projected temperature-mortality burden in the future. Researchers should ensure that all future impact assessments include adaptation uncertainty in projections and assumptions are based on empirical evidence. [ABSTRACT FROM AUTHOR]

A solid inclusion is embedded in a soft matrix supported by a rigid substrate. To simulate finger palpation, a spherical indenter exerts a vertical load on the matrix surface, followed by a lateral motion. A deep inclusion first rises close to the surface, dives under the indenter, and emerges from the leeside of the traversing indenter. The inclusion trajectory is essentially symmetric about the axis where the inclusion lies. A shallow inclusion is first pushed sideways, but an instability causes it to jump spontaneously to the rear following an asymmetric path. Such instability is a specific feature in hyperelastic materials. [ABSTRACT FROM AUTHOR]

A binder-free Ni (oxy)hydroxide on Ni foam was prepared through an in-situ electrochemical activation method. Ni (oxy)hydroxide is active for the oxygen evolution reaction. The Ni (oxy)hydroxide directly formed on the surface of Ni foam as a binder-free catalyst not only exhibited large electrochemically active area, but also displayed low interfacial electronic resistance and low charge transfer resistance. Therefore, the optimized Ni (oxy)hydroxide exhibits an overpotential of 288 and 370 mV at 10 and 500 mA cm−2, respectively, in 1.0 M KOH for the oxygen evolution reaction, as well as favorable during 240 h at 100 mA cm−2. • Electrochemical activation method is a time and energy-saving method. • Strong electronic interaction between NiOOH and Ni favors electron transfer. • High valence Ni in NiOOH enhances the chemisorption of OH− during OER. • In situ formation of NiOOH layer reduces the interfacial electronic resistance. [ABSTRACT FROM AUTHOR]

Pediatric intracranial aneurysms are extremely rare. In this age group, cerebral vascular anomalies have been associated with the development of intracranial aneurysms. We present a case of a previously well 11-year-old boy who presented with seizures secondary to a giant, unruptured, and partially thrombosed right middle cerebral artery (MCA) aneurysm. Extensive workup for underlying infective and autoimmune etiology was negative. Of interest, this vascular lesion was found to originate from an anomalous M2 branch, which ran an aberrant parallel course within the Sylvian fissure to the main and distally bifurcating MCA. The patient underwent successful surgical clipping and excision of the giant aneurysm. Because of the infrequency of the diagnosis, clinical presentation, and its unique neurovascular anatomy, the management of this case is discussed in corroboration with current literature. In addition, highlighting this unusual case in an individual adds to the growing body of literature for better disease understanding, especially in the pediatric population. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metagenome sequencing reveals changes in functional genes under the impact of Ce(III). • The performance of the reactor began to drop when the Ce(III) content got to 25 mg/L. • Elevated Ce(III) concentration leads to shift of the dominant anammox bacteria. • Ca. brocadia and Ca. jettenia also have genes for other nitrogen metabolic pathways. • Ce(III) increased the abundance of functional genes associated with EPS production. The high Ce(III) content in ionic rare-earth tailings wastewater has hindered the application of anammox process in this field. Here, the effect of Ce(III) on the performance of anammox processes was investigated, and the evolution of microbial communities and functional genes was explored using metagenomic sequencing. The results showed that the reactor nitrogen removal rate decreased when the Ce(III) concentration reached 25 mg/L, although ammonia nitrogen removal (92.31%) and nitrogen removal efficiency (81.33%) remained at a high level; however, both showed a significant decreasing trend. The relative abundance of anammox bacteria increased continuously from P1–P5, reaching 48.81%, whereas the relative abundance of Candidatus jettenia reached 33.71% at P5, which surpassed that of Candidatus brocadia as the most abundant anammox bacteria, and further analysis of functional genes and metabolic pathways revealed that Candidatus brocadia was richer in biochemical metabolic genes, whereas Candidatus jettenia had richer efflux genes. [ABSTRACT FROM AUTHOR]

Highlights • Automatic STN detection improves the efficiency and accuracy of target location. • Both spike independent and dependent features are useful for detection of STN. • Further research required for STN sub territories. Abstract Objective This study seeks to systematically review the selection of features and algorithms for machine learning and automation in deep brain stimulation surgery (DBS) for Parkinson's disease. This will assist in consolidating current knowledge and accuracy levels to allow greater understanding and research to be performed in automating this process, which could lead to improved clinical outcomes. Methods A systematic literature review search was conducted for all studies that utilized machine learning and DBS in Parkinson's disease. Results Ten studies were identified from 2006 utilizing machine learning in DBS surgery for Parkinson's disease. Different combinations of both spike independent and spike dependent features have been utilized with different machine learning algorithms to attempt to delineate the subthalamic nucleus (STN) and its surrounding structures. Conclusion The state-of-the-art algorithms achieve good accuracy and error rates with relatively short computing time, however, the currently achievable accuracy is not sufficiently robust enough for clinical practice. Moreover, further research is required for identifying subterritories of the STN. Significance This is a comprehensive summary of current machine learning algorithms that discriminate the STN and its adjacent structures for DBS surgery in Parkinson's disease. [ABSTRACT FROM AUTHOR]

The thermal, mechanical and durability properties of lightweight strain hardening cementitious composite (LSHCC) as well as the effectiveness of using LSHCC for structural retrofitting of unreinforced masonry (URM) wall is reported in this study. The proper range of water content, dosage of superplasticiser and viscosity modifying agent was explored from the survivability test of glass micro hollow bubble (3M-S15), which was much more fragile but effective in reducing the thermal conductivity of the composite than other studies. Then, the tensile properties of LSHCC with plastic-state density of about 1300–1400 kg/m 3 from different proportion of replacement of ordinary Portland cement (OPC) by fly ash (FA) and ground granulated blast-furnace slag (GGBS) as well as different volume fraction of polyvinyl alcohol (PVA) fibre were measured. The tensile ductility of LSHCC of replacement by FA was in general better than pure OPC or with GGBS blends. The tensile strength and ductility of LSHCC with 1.75% volume fraction of PVA fibre was about 3 MPa and 2–4%, respectively. The compressive strength ranged from 14 to 31 MPa. The thermal conductivity of selected LSHCC ranged from 0.34 to 0.51 W/m·K. The coefficient of water permeability of LSHCC was comparable with reference normal concrete and the engineered cementitious composite (ECC-M45) in the literature. The coefficient of chloride diffusivity of most LSHCC in this study was lower than the reference concrete because of the chloride binding of FA and GGBS. However, the carbonation rate of the LSHCC was generally higher. Three sets of LSHCC with similar tensile strength but different ductility were chosen for the evaluation of the effectiveness on structural retrofitting of an unreinforced masonry wall by in-plane and out-of-plane pushover analysis. The parameters of a finite element model with smeared crack material model was tuned based on the stress-strain relationship of LSHCC measured from the tensile tests in this study. There was no improvement of using LSHCC with 0.6% tensile ductility. By applying a 10 mm thick LSHCC with 2.2% and 4.4% tensile ductility on each side of an URM wall, the ductility of the retrofitted wall under in-plane loading was increased by 38% and 72%, respectively while it was increased by 164% for both kinds of LSHCCs for out-of-plane loading. [ABSTRACT FROM AUTHOR]

Prefabricated lightweight concrete building fasçade can improve the energy efficiency of buildings and reduce the carbon emission of transportation. However, it is essential to maintain the dimensional stability of the full scale element. The drying shrinkage of lightweight foamed concrete was investigated in this study. The hypothesis of using the drying shrinkage of normal weight concrete to approximate that of lightweight foamed concrete of dry density about 1500 kg/m 3 counterpart was verified. Three different strategies of reducing drying shrinkage were studied. The drying shrinkage of common ingredients of ordinary Portland cement (OPC) and ground granulated blast-furnace slag (GGBS) was commonly up to 2000–3000  μ ε . The use of magnesium expansive agent with different calcination conditions could not reduce the drying shrinkage. The use of calcium sulfoaluminate (CSA) cement with OPC and GGBS could significantly reduce the drying shrinkage within 1000  μ ε in standard testing environment. The formulation developed in laboratory was scaled up in a concrete production plant for prefabricated concrete elements. A lightweight full scale panel (the wet density was about 1700 kg/m 3 ) was fabricated. The drying shrinkage of the developed formulation with CSA cement was only 161  μ ε in the field test. A hygro-mechanical model was developed to model the diffusion, shrinkage and plastic strain evolution. The incremental stress-strain constitutive relationship of the hygro-mechanical model was derived for incorporating it into general finite element routine. The model parameters were calibrated by the drying shrinkage measurements in this study. The calibrated model demonstrated the cracking potential of three typical reinforced concrete panels of three different formulations studied in this study. [ABSTRACT FROM AUTHOR]

An ultrathin (thickness 1.0 nm) 2D nitrogen-doped hierarchically porous carbon (2DNHPC) film is developed by the nanocasting method; for comparison, a 3D nitrogen-doped ordered mesoporous carbon (3DNOMC) is also synthesized. Characterizations reveal that 2DNHPC is featured by an extremely high aspect ratio (several hundred) and a bimodal pore distribution. Such a 2D hierarchically porous structure is found to facilitate both the mass transfer of the reactive species and the utilization of active site in the electrode. First, 2DNHPC yields a larger limiting current than does 3DNOMC for the oxygen reduction reaction (ORR), revealing the key role of the low dimensional structure to facilitate the mass transfer. Second, at the loading of 500 μg cm −2 , 2DNHPC shows the same kinetic current with 3DNOMC, indicating that the two catalysts have the same active site and turnover frequency. In comparison, at a lower loading of 250 μg cm −2 , the kinetic current of 2DNHPC remains unchanged, which however seriously deteriorates for 3DNOMC. This result strongly highlights the effect of the carbon dimension on the utilization efficiency of the active site. Finally, it is noted that 2DNHPC yields a comparable ORR electrocatalytic activity and long-term stability with commercial Pt catalyst in both alkaline and acid media. [ABSTRACT FROM AUTHOR]

The effect of the pore structure of SBA-15, which is tuned by varying the hydrothermal temperature (90–150 °C), is investigated on nitrogen-doped ordered mesoporous carbon. It is found that the pore structure of SBA-15 yields effects on both the composition and the pore structure of carbon, which thereby affecting its electrocatalytic activity for the oxygen reduction reaction (ORR). XPS reveals that the nitrogen content of the template-free carbon is 2.79 at.%, while dramatically increases to 4.48, 5.01 and 4.16 at.% for the three template-aided carbon catalysts with SBA-15 synthesized at 90, 130 and 150 °C, respectively. Nitrogen ad/desorption isotherms show that the specific surface area of the template-free carbon is 257 m 2 g −1 , which increases to 724, 731 and 691 m 2 g −1 for the above three carbons. Such changes correlate well with the electrochemical results. RRDE results show that the template-aided carbon catalysts yield better activity and selectivity for the ORR than does the template-free one. And the best performance is achieved for the carbon catalyst with SBA-15 synthesized at 130 °C, which coincidentally has the highest nitrogen content and surface area. [ABSTRACT FROM AUTHOR]

Hexagonal Bi 2 Te 3 nanosheets with uniform morphology were facilely synthesized through a hydrothermal method at 180 °C. X ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and selected area electron diffraction (SAED) were employed to characterize the Bi 2 Te 3 nanosheets. The results clearly indicate that uniform Bi 2 Te 3 nanosheets with a side length of 300–400 nm were obtained. Bi 2 Te 3 nanosheet/ZnO nanoparticle (Bi 2 Te 3 NS/ZnO NP) composite photoanodes were fabricated with Bi 2 Te 3 NS concentration in the range of 0–0.25 at.%. The effect of Bi 2 Te 3 NS contents in composite photoanode on the performance of dye-sensitized solar cells (DSSCs) was systematically investigated. The photocurrent density-voltage ( J-V ) characteristics indicate that the DSSCs with Bi 2 Te 3 NS/ZnO NP composite photoanode exhibit significantly improved photovoltaic performance. Typically, the highest energy conversion efficiency of 4.10% which is increased by 46.95% compared with that of the bare ZnO can be achieved in the DSSC with 0.15 at.% Bi 2 Te 3 NS embedding. The EIS results further confirm that a moderate amount of Bi 2 Te 3 NS in photoanode could not only improve the electrons transport and suppress the charge recombination rate, but also enhance the electron collection efficiency. Furthermore, the excellent thermoelectric performance of Bi 2 Te 3 NS in the photoanode could greatly increase the electron density and lower the temperature of the DSSCs effectively. All these results suggest that the Bi 2 Te 3 NS/ZnO NP composite photoanode could highly enhance the performance of the DSSCs. [ABSTRACT FROM AUTHOR]

Covalent organic framework (COF) is a novel platform to develop efficient and green safe heterogeneous photocatalysts. Additionally, multiple photoredox reactions and mechanism studies over porous catalysts remain to be further exploited. In this context, two benzofuran-embedded COFs (BF-COFs) with favorable solvent tolerance were constructed via tautomerism strategy. Attributing to the benzofuran-hetero[6]radialene knots, BF-COFs displayed as donor-acceptor properties, and exhibited wide visible light response range and well separation efficiency for photogenerated charges. Under visible-light, BF-COFs could promote the C-S bond formation reaction between β-ketoate ester and its analogues with NH 4 SCN, affording multi-substituted olefins (28 examples, upto 98% yield) efficiently. Moreover, the atomic economic strategy was also applicative to prepare L -proline derived olefins (≥ 99% ee), which could be further converted into the chiral amino-substituted thiazoles (99% yield and ≥ 99% ee). The research about BF-COFs sheds light on the green construction of C-S bond, (chiral) olefins and chiral amino thiazoles. [Display omitted] • Two benzofuran-heteroradialene joints-embedded BF-COFs were facilely constructed and proved to be donor-acceptor structures. • BF-COFs exhibit remarkable photocatalytic activity for the synthesis of multi-substituted olefins with upto 98% yield (28 examples). • BF-COFs can promote the synthesis of L -proline-derived olefins and amino-substituted thiazoles with maintained chirality (≥ 99% ee). • The photocatalytic mechanism for multi-substituted olefins synthesis were elaborated in detail. [ABSTRACT FROM AUTHOR]

[Display omitted] • Increasing the substrate concentration helped to improve the reactor tolerance. • In the P2 phase, side reactions impeded the removal of NO 2 –-N. • Filamentous bacteria, Ca and P synergistically promoted sludge granulation. • Anammox bacteria were reciprocal symbiosis with some heterotrophic bacteria. Most of the current studies have focused on the inhibition of anaerobic ammonium oxidation (anammox) by substrates, however, little attention has been paid to the recovery process of the reactor after inhibition. Therefore, we investigated the changes in reactor performance, granular sludge structure, and microbial community during the recovery phase after being inhibited by a high nitrogen load for 15 d. The nitrogen removal rate of the reactor was restored to pre-inhibition levels after 75 d of recovery, and the stoichiometric ratio converged to the theoretical value. The surface of the granular sludge developed into a broccoli-like structure, and the Ca and P contents of the granules increased from 6.88% and 4.39% to 24.42% and 13.88%, respectively. The abundance of the anammox bacterium Candidatus brocadia increased from 5.86% to 12.10%, and network analysis indicated that SMA102 and SBR1031 were positively correlated with the occurrence of Candidatus brocadia. [ABSTRACT FROM AUTHOR]

A solid inclusion is embedded at a depth in a hyperelastic soft matrix resting on a rigid substrate. External compression is applied via an indenter vertical to the substrate, but the loading axis is misaligned with the inclusion. In case of large offset distance, the inclusion dodges the advancing indenter by moving laterally. For small offset, the inclusion moves vertically downward initially but turns abruptly sideways once the indenter reaches a critical depth. The unique behavior of gel under large elastic deformation is investigated by finite element analysis. Southwell subcritical extrapolation method is used to estimate the maximum indentation depth before a lateral displacement of the inclusion becomes inevitable. • An inclusion is embedded in a soft matrix. • Indentation axis is slightly misaligned with the inclusion. • Once indenter reaches a critical depth, inclusion experiences an unstable lateral motion. • Initial nearly symmetric stress field thus becomes asymmetric. [ABSTRACT FROM AUTHOR]

Abstract: Recently, numerical solutions of stochastic differential equations have received a great deal of attention. Numerical approximation schemes are invaluable tools for exploring their properties. In this paper, we introduce a class of stochastic age-dependent (vintage) capital system with Poisson jumps. We also give the discrete approximate solution with an implicit Euler scheme in time discretization. Using Gronwall’s lemma and Barkholder–Davis–Gundy’s inequality, some criteria are obtained for the exponential stability of numerical solutions to the stochastic age-dependent capital system with Poisson jumps. It is proved that the numerical approximation solutions converge to the analytic solutions of the equations under the given conditions, where information on the order of approximation is provided. These error bounds imply strong convergence as the timestep tends to zero. A numerical example is used to illustrate the theoretical results. [Copyright &y& Elsevier]

Abstract: A one-dimensional (1-D) rectangular pre-stressed thin film clamped at two opposite ends is actuated by an electrostatic voltage applied to a pad directly underneath. The pre-stress is allowed to be either tensile or compressive in nature. At a critical applied voltage, the film becomes unstable and makes direct contact with the pad, leading to “pull-in”. An elastic model is constructed to account for the phenomenon over ranges of film–pad gap and residual stress. The results compare favorably with finite element analysis (FEA) in literature and experimental data, and possess distinct advantages over other available closed-form solutions. The model is further extended to a two-dimensional (2-D) axisymmetric diaphragm clamped at the periphery. Interrelationship between bridge–pad gap, residual membrane stress, critical voltage, and pull-in central deflection is derived such that new design criteria can be derived for micro-/nano-electromechanical devices. Implications for nano-structures are also discussed. [Copyright &y& Elsevier]

Abstract: In this paper, it is considered for a class of stochastic age-structured population equations with diffusions and Markovian switching. Most kind of equations are nonlinear and cannot be solved explicitly, so the construction of efficient computational methods is of great importance. The main aim of this paper is to develop a numerical scheme and investigate the convergence of numerical approximation. An example is given for illustration. [Copyright &y& Elsevier]

Abstract: The main aim of this paper is to investigate the exponential stability of the Euler method and the semi-implicit Euler method for stochastic delay Hopfield neural networks. The definition of MS-stability and GMS-stability of these two numerical methods is introduced. Under the conditions which guarantee the stability of the analytical solution, the Euler scheme is proved to be MS-stable and the semi-implicit scheme is to be MS-stable and GMS-stable. An example is given for illustration. [Copyright &y& Elsevier]

The provision of climate services for assessing and governing environmental problems such as poor air quality requires interactions between scientists and decision-makers. Air quality information services in China mainly focus on the coming days to weeks. However, users may benefit from air quality information on climate time-scales—from months to decades; hereafter air quality climate services. We focused on key decision-makers and stakeholders that are users of air quality climate services and conducted five workshops with these identified users to ascertain their priorities for air quality climate services, and the reasoning behind these priorities. We also conducted a choice-based conjoint experiment via an online survey distributed amongst regional and local Climate Centres and Environmental Monitoring Centres to assess quantitatively the decision-makers' needs. The results from the workshops and the survey showed that the needs for air quality climate services by users in China mainly relate to seasonal forecasting of winter haze events (PM 2.5 levels and/or the meteorological conditions conducive to the dispersion of the air pollution); there is also some interest in long-term projections of haze under climate change and a growing interest in ozone pollution in summer. Spatial relevance is perceived to be important to regional and city-level stakeholders who prefer information on the city-level, whilst national-wide information is important for national government agencies. A high level of reliability of forecasts was needed for uptake. The findings on the needs for air quality climate services by potential users can support researchers and policy-makers in developing the scientific capacity and providing tailored and effective air quality climate services in China. • To understand decision-maker needs on air quality climate services, qualitative and quantitative methods were conducted, and the results were compared and combined. • Decision-makers and stakeholders expressed a strong interest for seasonal forecasting for winter haze. • They also expressed a moderate interest for seasonal forecasting for summer ozone pollution, and a modest interest for long-term projections of haze under climate change. • A high level of reliability of forecasts was needed for uptake while multiple sources of uncertainties were recognised. [ABSTRACT FROM AUTHOR]

Abstract: The degradation of concrete structures is always accompanied by the formation of cracks. If cracks are detected at an early stage before significant degradation occurs, life of the structure can be extended by the performance of relatively low cost but timely maintenance measures. To detect and monitor cracking in concrete structures, where the crack locations are often not known in a-priori, a distributed optical crack sensor based on OTDR measurement of bend loss has been developed. In this paper, the sensing principle will be discussed and the fabrication of sensors for surface attachment and internal embedment is described. Experimental results are shown to demonstrate that the optical power loss versus crack opening relation at a particular point of bend loss is independent of the number of bends along the fiber. Then, the monitoring of single and multiple cracks under quasi-static loading is illustrated, followed by the detection of cracks under restrained dimensional change (caused by shrinkage or thermal effects). Finally, the sensor performance under cyclic loading is studied. Based on the test results, the potential of the sensor for practical applications is demonstrated. [Copyright &y& Elsevier]

Abstract: Cracks in structures may open in mixed mode under general loading conditions. In other words, there are both opening and shearing displacements along the crack. In our former work, a distributed fiber optic sensor has been developed for the detection and monitoring of purely opening cracks (or Mode I cracks). The sensing principle is based on the bending loss of an optical fiber intersecting the opening crack at an angle other than 90°. In the present work, the sensing concept is extended to the monitoring of mixed mode cracks. To obtain both the opening and shear displacements at the crack, two independent measurements are required. Based on theoretical simulation, the feasibility of various sensing strategies, including the use of two wavelengths and two fibers, are first investigated to identify the most promising approach. A method to solve the inverse problem of obtaining the crack displacements from the measured signal losses is then derived. Experiments are performed under controlled crack opening/shearing history to verify the sensing approach. Good agreement between derived opening/shearing displacements and imposed displacements has been obtained. [Copyright &y& Elsevier]

Abstract: The adhesion of films and coatings to rigid substrates is often measured using blister geometries, which are loaded either by an applied pressure or a central shaft. The measurement will be affected if there are residual stresses that make a contribution to the energy release rate. This effect is investigated using analytical solutions based on the principle of virtual displacements. A geometrically nonlinear finite element analysis is conducted for comparison. Furthermore, the relationships among strain energy release rate, load, deflection, and fracture radius are discussed in detail. Both analytical solutions and numerical results reveal that uniform tensile residual stresses reduce a specimen’s deflection if it experiences plate behavior under small loads. However, this effect becomes negligible when membrane stresses induced by the loading become dominant. [Copyright &y& Elsevier]

The strain energy release rate, G, is derived from first principles and is shown to be consistent with the exact numerical solution by Cotterell and Chen (Int. J. Fract. 86 (1997) 191). Comparison with the classical Rayleigh–Ritz energy method and other published methods shows that the gradual change in blister profile over the entire loading process must be considered for the correct G to be calculated. [Copyright &y& Elsevier]

An accurate closed-form analytical solution for the strain energy release rate for a thin rectangular film loaded by a central line force using the pull-off test is derived in the presence of a tensile residual stress. The theoretical constitutive relation and the strain energy release rate agree very well with two-dimensional nonlinear finite element analysis for the entire deformation regime ranging from bending plate to stretching membrane. Fracture modes for this pull-off test are also investigated based upon the finite element analysis, offering additional insights to the interfacial delamination. [Copyright &y& Elsevier]

Tensile residual stress in a plate or membrane clamped at the perimeter can be measured by either applying a uniform hydrostatic pressure or a central load via a cylindrical punch (with several different loading configurations). Analytical constitutive relations are derived here based on an average membrane stress approximation and are compared to finite element analysis results. The thickness and flexural rigidity of the film are not confined to a small range but will span a wide spectrum. The elastic responses of the blistering films are shown to be linear when the film is thick, relatively rigid, or subjected to a large residual stress, and cubic when the film is thin, flexible, or under a small residual stress. The linear-to-cubic transition is formulated. [Copyright &y& Elsevier]

A new theoretical model is presented for the mechanical response of a thin-walled bio-mimetic microcapsule upon indentation using an atomic force microscope. The membrane is strained by both bending moments and membrane stress in the presence of a tensile pre-stress. When the intrinsic membrane stress is large compared to the local stress around the indentation dimple, the constitutive relation is linear; and when it is small, a cubic relation is deduced. The new theory is rigorously compared to the existing models of: (i) membrane under pure bending by Boulbitch; and (ii) membrane under pure stretching by Yao et al., which are shown to be two limiting cases of our general solution. Published experimental data in literature show that AFM measurement always involves deformation mode of mixed bending and stretching. [Copyright &y& Elsevier]

A new theoretical model was developed for a pull-off adhesion test using an axisymmetric flat punch and a rectangular flat punch adhered to a thin polymer film interface. An elastic solution was derived to portray the mechanical integrity of the thin film. A mechanical energy release rate was calculated numerically. As the punch was pulled away from the adhered film, the film deformed under mixed bending and stretching. Both stiffness and thickness of the film were allowed to vary. The derived solid-film ‘pull-off’ events sharply contrast with the abrupt pull-off in solid–solid adhesion as predicted by the classical JKR theory. [Copyright &y& Elsevier]

The correlation between the mechanical property and the thermotropic transition of the phospholipid bilayer has been recently demonstrated (Chem. Phys. Lipids 110 (2001) 27). However, the role of thermal induced mechanical responses of phospholipid bilayer on the contact mechanics of liposome adhering on a cationic substrate has not been determined. In this study, confocal-reflectance interference contrast microscopy, phase contrast microscopy and contact mechanics modeling are applied to probe the adhesion mechanisms of liposomes in the presence of electrostatic interactions during the thermotropic transition of the lipid bilayer. When temperature increases from 23 to 49 °C at pH 7.4, the degree of liposome deformation (a/R) and adhesion energy of dipalmitoyl-sn-glycero-3-phosphocholine liposome increases by 10% and remains constant, respectively, on 3-amino-propyl-triethoxy-silane (APTES) modified substrate. The extents of increase in these two parameters are highly dependent on the physicochemical properties of the rigid substrate. At pH 4, the adhesion energies above and below the phase transition temperature (Tm) are increased by one order of magnitude due to the formation of the free silanol groups on APTES substrate. In hypotonic condition, the degree of vesicle deformation remains constant and the adhesion energy reduces by 20% during sample heating. Under all conditions, the adhesion energy of the adhering liposome spans a few orders of magnitude against the increase of liposome size as the surface area to volume ratio is maximized in smallest vesicle. [Copyright &y& Elsevier]

The physiochemical properties of phospholipid vesicle, e.g. permeability, elasticity, etc., are directly modulated by the chain-melting transition of the lipid bilayer. Currently, there is a lack of understanding in the relationship between thermotropic transition, mechanical deformation and adhesion strength for an adherent vesicle at temperature close to main phase transition temperature Tm. In this study, the contact mechanics of dimyristoyl-phosphatidylcholine (DMPC) vesicle at the main phase transition are probed by confocal reflectance interference contrast microscopy in combination with phase contrast microscopy. It is shown that DMPC vesicles strongly adhere on pure fused silica substrate at Tm and the degree of deformation as well as the adhesion energy is a decreasing function against the mid-plane diameter of the vesicles. Furthermore, an increase of osmotic pressure at the gel/liquid crystalline phase co-existence imposes insignificant changes in both the degree of deformation and adhesion energy of adherent vesicles when the lipid bilayer permeability is maximized. With the reverse of substrate charge, the mechanical deformation and adhesion strength for larger vesicles (mid-plane diameter >18 μm) are significantly reduced. By monitoring the parametric response of substrate-induced vesicle adhesion during main phase transition, it is shown that the degree of deformation and adhesion energy of adhering vesicle is increased and unchanged, respectively, against the increase of temperature. [Copyright &y& Elsevier]

This paper is concerned with the inversion of confluent Vandermonde matrices. A novel and simple recursive algorithm for inverting confluent Vandermonde matrices is presented. The algorithm is suitable for classroom use in both numerical as well as symbolic computation. Examples are included to illustrate the proposed algorithm. [Copyright &y& Elsevier]

• The relationship between moving bodies on the rotary table is presented based on kinematic theory. • Separately identification method for position independent geometric errors by double ball bar is presented. • A novel optimization identification method for identification of position dependent geometric errors is proposed. • The influence of installation errors on geometric errors identification is investigated based on sensitivity analysis. For the redundancy in definition of position independent geometric errors(PIGEs) and position dependent geometric errors(PDGEs), it is difficult to identify all geometric errors of rotational axis simultaneously. A novel identification method using boundaryless constraint optimization method(BCOM) is established to improve PIGEs and PDGEs identification accuracy of rotary axis. For PIGEs, the two different dimension errors are identified separately based on least square method through appropriate measurement direction by double ball bar(DBB), and thus decrease condition number of identification matrix. For PDGEs, the B-spline curve is applied to fit the geometric errors and the objective function has been established. Several measurement paths are conducted and geometric errors are figured out by iterations of objective function. Furthermore, setup errors of DBB are investigated and discussed based on the sensitivity analysis. Finally, Simulations and experiments are conducted and their results demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

• Microelectrode recordings performed during DBS surgery are stochastic and non-stationary, therefore, their interpretation is challenging. • Wavelet packet based features are explored to localize the pre-STN, STN and post-STN. • k - N N , support vector machine and random forest models are designed to detect the STN. • Proposed system achieves a maximum average accuracy of 85.01 % in the classification non-STN vs. STN with random forest. • Proposed method is a fast and reliable, therefore, it may facilitate real-time intraoperative STN identification. Deep brain stimulation (DBS) to the subthalamic nucleus (STN) is an effective neurosurgery that overcomes the motor system alternations of patients with advanced Parkinson's disease. The most challenging aspect of DBS surgery is the accurate identification of STN and its borders. In general, it is performed manually by a neurophysiologist using the microelectrode recordings (MERs). This process is subjective, and tedious and further, interpretation of MERs is difficult because of its inherent nonstationary variations. In this work, the wavelet-packet based features are proposed to automatically localize the STN and its subcortical structures using microelectrode recorded signals during DBS surgery. The study analyses 2904 MERs of 26 PD patients who underwent DBS implantation. The low and high order statistical parameters are extracted from the wavelet packet coefficients of MERs and used in the classifications, namely, non-STN vs. STN, pre-STN vs. STN and STN vs. post-STN. Most of the features are significantly different in STN and its subcortical regions, namely, pre-STN and post-STN. The proposed features achieve an average accuracy of 85 % in non-STN vs. STN, 87.2 % in pre-STN vs. STN and 77.7 % in STN vs. post-STN. The accuracy is improved by around 10 % in non-STN vs. STN and STN vs. post-STN when the transition error is 1 mm. The proposed features are found to be better than the wavelet features. The proposed approach could be a potential useful adjunct for the real-time rapid intraoperative identification of STN and its anatomical borders. [ABSTRACT FROM AUTHOR]

Understanding the impact of climate stressors on photovoltaic (PV) backsheet degradation in real-use conditions is critical to improve the accelerated testing exposures, extend the backsheet lifetime, and increase the confidence in PV reliability. In this work, a total of 33 PV module backsheets were retrieved from six climatic zones worldwide with 2 - 28 years of exposure. These modules included five types of backsheet air-side materials (or outer layer): poly(vinylidene fluoride) (PVDF), poly(tetrafluoroethylene-co-hexafluoropropylene-co-vinylidene fluoride) (THV), poly(vinyl fluoride) (PVF), poly(ethylene terephthalate) (PET), and polyamide (PA). Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) was used to identify air-side materials. The degradation induced color change, gloss loss, and chemical material changes analyzed using optical microscopy, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), colorimetry (yellowness index (YI)), and gloss measurements. PVDF, THV, and PVF air-side layer backsheets, in particular PVF, had minimal degradation in the air-side layer appearance and chemical structures after exposure in different climatic zones. The PET air-side backsheets exhibited obvious color increase (22.55 YI units after about 9 years exposure) and the PA/PA/PA backsheets showed large gloss loss (up to 76.4 %) relative to the unexposed backsheets. Severe cracks between cells that penetrated through the entire thickness of backsheets are observed on PA/PA/PA backsheets after 4-6 years of exposure in 6 climatic zones. The current indoor exposure standards were not sufficient to identify this degradation type. However, fluoropolymer based PV backsheets showed lower levels of degradation predictors and increased climatic resistance. Specific samples (PVF) showed little change from baseline after 28 years of outdoor exposure. • Retrieved module backsheet characterization. • Diverse climatic exposure. • Inhomogeneous backsheet degradation. [ABSTRACT FROM AUTHOR]

A facile high-temperature molten salt bath method was developed to effectively dope sulfur into carbon. Molten potassium sulfide acts as a high-concentration sulfur source and provides an immersion bath, thus favoring sulfur doping. Resultant sulfur-doped carbon shows an exceptionally high sulfur content of 1.50 at.%, manifesting its favorable effect on catalysing the oxygen reduction reaction. [ABSTRACT FROM AUTHOR]

Mispositioning of microelectrodes during deep brain stimulation surgery can incur serious complications for patients. Current practice of creating a burr hole for introduction of the microelectrode is done freehand and can cause trajectory misalignment. We aimed to create a sterilizable surgical adjunct to minimize error from burr hole placement. We designed and demonstrated clinical use of a 3D-printed surgical jig that can be mounted to the current Cosman-Roberts-Wells stereotactic frame. The jig allowed accurate placement of the perforating burr for creation of the burr hole. Intraoperative usage of the jig in 11 patients who underwent bilateral deep brain stimulation microelectrode placement for Parkinson disease demonstrated high accuracy of microelectrode placement, with an average 1.18 mm deviation (range, 0–2.7 mm) from intended trajectories. No intraoperative complications were encountered. This proof-of-concept study highlights the utility of 3D-printed surgical adjuncts that are fully customizable and rapidly produced to improve current surgical practice. The jig reduced surgery duration, need for multiple trajectories, and risk of potentially devastating neurological complications. As demonstrated, 3D-printed devices are useful as surgical adjuncts to optimize safety and efficacy in deep brain stimulation surgeries. [ABSTRACT FROM AUTHOR]

Nitrogen-doped ordered mesoporous carbon (NOMC) is studied as the support to synthesize a Pt/C N-doped catalyst for methanol oxidation reaction (MOR). The effects of carbon dimension and metal loading are investigated by nitrogen ad/desorption isotherms, transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical methods. Both TEM and XRD results show that platinum nanoparticles (Pt NPs) are highly dispersed on NOMC with a uniform and narrow distribution, while the dimension of NOMC has a considerable effect on the dispersion of Pt. For 10 wt% metal loading, the average diameter of Pt NPs on 2D-NOMC is 1.40 nm; smaller than that on 3D-NOMC (1.90 nm). XPS results reveal that a strong electronic interaction exists between Pt and NOMC, indicating the formation of Pt–N bonds at the interface. Such an interaction gets more pronounced in the case of low Pt loadings and low-dimensional supports; the reason is that the 2D support is more accessible to load Pt and the metal-support interface is better developed at low metal loadings. The electrochemical results are well correlated with the physiochemical characterizations. 1) The electrochemically active surface area of Pt is higher on the 2D-support than that on the 3D-one, confirming the better dispersion of Pt on NOMC-2D. 2) A positive shift in the potential is observed for the adsorption of oxygen-containing species onto Pt, which is indicative of the charge transfer from Pt to the support and the formation of Pt–N bonds. 3) Both onset and peak potentials are negatively shifted by ca . 50 mV for MOR on 10 wt% Pt/NOMC-2D, as compared with the commercial Pt/XC-72. The ratio of forward to backward current, a measure of poisoning tolerance, is 1.1 on Pt/NOMC-2D and 0.80 on Pt/XC-72R. This enhancement can be attributed to the bifunctional mechanism at the Pt/C N-doped interface. In MOR, CO-like intermediate species on Pt can be effectively stripped off by the adjacent active –OH species on carbon, generated at lower potentials. [ABSTRACT FROM AUTHOR]

A spherical inclusion is embedded in a soft gel block. A vertical force is applied on the gel surface by means of a spherical indenter. The loading axis is not aligned with the inclusion but placed at a horizontal offset displacement from the inclusion. The measurement of indentation force and inclusion trajectory are compared to the computational results from two-dimensional (2D) Finite Element Analysis (FEA) simulations. A discernible instability emerges when the indentation reaches a critical depth, in accordance with the Southwell instability theory. The three-dimensional (3D) trajectory shows distinct features that were previously not captured by the 2D FEA simulations. • Cancer tumor in body tissue is modeled as solid spherical inclusion embedded in a soft gel matrix. • Indentation on gel surface leads to unstable lateral motion of an inclusion aligned with the loading axis. • Behavior of off-axis inclusions can be predicted by the classical Southwell instability theory. • Mechanical force on the indenter is consistent with finite element analysis. • A viable model is established for palpation mechanics. [ABSTRACT FROM AUTHOR]

• Two PET-based backsheets were exposed to indoor UV accelerated weathering. • Single cantilever beam (SCB) tests were used to measure the adhesion in the backsheets. • Both backsheets showed high initial (unweathered) adhesion energies. • After moderate exposure, the polyurethane-based adhesives showed significant adhesion loss. • After high exposure, the PET outer layer showed appreciable UV-induced surface degradation. Delamination between layers in photovoltaic (PV) backsheets is often reported in the literature, causing voids that can collect moisture, diminish module backside heat dissipation, and reduce the backsheet's effectiveness as a physical barrier. While backsheets with weathering-resistant fluoropolymer outer layers have traditionally been used in modules, more recent backsheets using non-fluoropolymer outer layers, such as polyethylene terephthalate (PET), have been developed. These backsheets have shown signs of premature degradation, and their adhesion degradation, in particular, has not been widely studied. In the present work, the single cantilever beam (SCB) adhesion test was used to quantify the adhesion energy in two commercially available PET-based backsheets. To study the effect of minor changes in formulation, the backsheets were obtained from same manufacturer and product line but during different years. To study the effect of environmental variables on adhesion degradation, the backsheets were subjected to artificial weathering at controlled temperature, humidity, and ultraviolet (UV) radiation in an indoor weathering chamber, and the adhesion energy was quantified at several intervals of exposure time. Layering structure, composition, and adhesion failure mode were compared between the backsheets, using Raman and infrared spectroscopy and thermogravimetric analysis. The results show a large difference in initial (unexposed) adhesion energy between the backsheets, despite very similar structures and compositions. Following exposure, adhesion energy dropped significantly, primarily due to thermo-hydrolytic degradation of the polyurethane (PU)-based adhesive layers. Significant UV-induced adhesion degradation of the PET outer layer surface was also observed. The study represents an important step in understanding adhesion degradation in PET-based backsheets, suggesting ways in which adhesion integrity – and, correspondingly, module service life – can be improved. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a class of stochastic age-dependent population equations with Markovian switching is considered. The main aim of this paper is to investigate the convergence of the numerical approximation of stochastic age-dependent population equations with Markovian switching. It is proved that the numerical approximation solutions converge to the analytic solutions of the equations under the given conditions. An example is given for illustration. [Copyright &y& Elsevier]

Abstract: In this paper, a class of stochastic pantograph equations with Markovian switching is considered. The main purpose is to investigate the convergence of the Euler method of the equations. It is proved that the Euler approximation solution converge to the analytic solution in probability under weaker conditions. An example is provided to illustrate our theory. [Copyright &y& Elsevier]

Characterization of surface cracks is one of the key steps towards condititional assessment and understanding the durability of strain hardening cementitious composites (SHCCs). Under laboratory conditions, surface crack statistics can be obtained from images of specimen surfaces through manual inspection. This is subjective, time consuming and laborious. In order to automate this process a framework encompassing a deep learning model for rapid identification and computation of crack parameters of thin SHCC cracks in presented in this work. A tailored deep convolutiontional neural network (TDCNN) was trained to detect thin cracks and then crack parameters were computed using image processing technique. The proposed technique does not require optimal lighting conditions, proper surface treatment, and prior (manual) selection of the correct region for proper inference.. The results from the controlled study suggest that the inference ability of TDCNN is reasonably good, resilient against epistemic uncertainty and tunable for completely independent but adverse observations. From the crack pattern computed using TDCCN, crack parameters-average crack width (ACW) and crack density (CD) can be calculated to facilitate conditional and durability assessment in a practical environment. [ABSTRACT FROM AUTHOR]

It has been recently demonstrated that acyl chain mismatch of phospholipid bilayer composed of a binary lipid mixture induces component formation on the lateral plane of the bilayer [Biophys. J. 83 (2002) 1820–1883]. In this report, the contact mechanics of unilamellar vesicles composed of binary dimyristoyl-phosphatidylcholine (DMPC)/dipalmitoyl-phosphocholine (DPPC) mixtures on fused silica and amino-modified substrates is simultaneously probed by confocal-reflectance interference contrast microscopy (C-RICM) and cross-polarized light microscopy during gel to liquid crystalline transition of the lipid bilayer. C-RICM results indicate that the average degree of vesicle deformation for DMPC-rich and DPPC-rich vesicles adhering on fused silica substrate is increased by 30% and 14%, respectively, in comparison with that in pure DMPC and DPPC vesicles. Also, lateral heterogeneity induced by acyl chain mismatch increases the average magnitude of adhesion energy in DMPC-rich and DPPC-rich vesicles of all sizes by 6.4 times and 2.3 times, respectively. Similar modulation of adhesion mechanics induced by carbon chain difference is obtained on amino-modified substrate. Most importantly, the thermotropic transition of the mixed bilayer from gel (below Tm) to fluid phase (above Tm) further exemplifies the effect of acyl chain mismatch on the increases of degree of vesicle deformation and adhesion energy. [Copyright &y& Elsevier]

Adhesion of cells on biomaterial surface is resulted from the complex interplay of specific recognitions and colloidal interactions. Thus understanding the role of electrostatic interactions in bioadhesion may help to elucidate the physiochemical basis of cell signaling pathway on therapeutic devices. In this report, high-resolution reflection interference contrast microscopy, cross-polarized light microscopy and contact mechanics modeling are applied to probe the equilibrium adhesion of giant phospholipid vesicles on 3-amino-propyl-triethoxy-silane coated glass. Simultaneously, the effects of vesicle wall thickness, pH, osmotic stress and surface chemistry on the electrostatic interactions at the membrane–substrate interface are evaluated. The results show that both unilamellar vesicles (ULV) and multilamellar vesicles (MLV) strongly adhere on the cationic substrates at neutral pH. In the presence of electrostatic interactions, ULV is slightly deformed on the substrate as the dimension of its adhesive–cohesive zone is only 6–10% higher than the theoretical value of a rigid sphere with the same mid-plane diameter. The variances of contact angle and capillary length at different locations surrounding MLV are ten times higher than those of ULV. The adhesion energy of ULV with mid-plane diameter of 45 and 20 μm is determined as 3.8×10−12 and 8.6×10−12 J/m2, respectively, from the truncated sphere model. Moreover, the increase of osmotic stress induces irregular pattern in ULV''s adhesion disc and raises the adhesion energy by 10-fold. Finally, the reduction of pH further enhances the electrostatic attractions/repulsions between vesicle surface and cationic or anionic substrates and leads to an increase of adhesion strength. [Copyright &y& Elsevier]

High-resolution reflection interference contrast microscopy (HR-RICM) was developed for probing the deformation and adhesion of phospholipid vesicles induced by colloidal forces on solid surfaces. The new technique raised the upper limit of the measured membrane–substrate separation from 1 to 4.5 μm and improved the spatial resolution of the heterogeneous contact zones. It was applied to elucidate the effects of wall thickness, pH and osmotic stress on the non-specific adhesion of giant unilamellar vesicles (ULV) and multilamellar vesicles (MLV) on fused silica substrates. By simultaneous cross-polarization light microscopy and HR-RICM measurements, it was observed that ULV with the wall thickness of a single bilayer would be significantly deformed in its equilibrium state on the substrate as the dimension of its adhesive–cohesive zone was 29% higher than the theoretical value of a rigid sphere with the same diameter. Besides, electrostatic interaction was shown as a significant driving force for vesicle adhesions since the reduction in pH significantly increased the degree of deformation of adhering ULV and heterogeneity of the adhesion discs. The degree of MLV deformation on the solid surfaces was significantly less than that of ULV. When the wall thickness of vesicle increased, the dimension of contact zone was reduced dramatically due to the increase of membrane bending modulus. Most important, the adhesion strength of colloidal adhesion approached that of specific adhesion. Finally, the increase of osmotic stress led to the collapse of adhering vesicles on the non-deformable substrate and raised the area of adhesive contact zone. To interpret these results better, the equilibrium deformation of adhering vesicle was modeled as a truncated sphere and the adhesion energy was calculated with a new theory. [Copyright &y& Elsevier]

Electroactive organics with multiple redox centers have advantage to realize high capacity and energy density of lithium-ion batteries (LIBs). Herein, a novel multiredox organic molecule, viz. 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPT), is developed by densely assembling active sites in one molecule, which yields reversible four-electron storage and a high capacity of 347 mA h g−1 TPT at 0.10 A g−1 in carbonate electrolyte. Battery test reveals a superior cyclability with a capacity retention of 66% after 6000 cycles at 2.0 A g−1 and rate performance. Physiochemical characterizations and theoretical calculation are extensively performed to clarify the superior capacity and stability. Physicochemical characterizations reveal that the TPT evolves to diradicals upon accepting two electrons, and the quinoid structure upon accepting four electrons. The effective delocalization of the four charge over the four aromatic rings can remarkably stabilize the organic molecule against side reactions. The formation of a cathode electrolyte interface film contributes to the high cyclability during the battery test. The capacitive response of TPT is recognized as the dominant proportion in capacity, which contributes to the superior rate performance. This work offers an effective strategy on the rational design of high-capacity and stable organic cathode materials for LIBs. Schematic illustration of TPT-based lithium-ion battery. [Display omitted] • TPT molecules was explored as the cathode material in lithium-ion batteries. • TPT cathode shows capability of reversible four-electron storage. • TPT cathode yields a high specific capacity of 347 mA h g−1 TPT. • TPT cathode shows a superior cyclability. • TPT cathode shows capacity retention of 66% after 6000 cycles. [ABSTRACT FROM AUTHOR]

A microfluidic device was designed to investigate filtration of particles in an electrolyte in the presence of liquid flow. Polystyrene spheres in potassium chloride solution at concentrations of 3–100 mM were allowed to settle and adhere to a glass substrate. A particle free solution at the same concentration was then flushed through the microfluidic channel at 0.03–4.0 mL/h. As the hydrodynamic drag on the adhered particles exceeded the intersurface interaction with the substrate, “pull-off” occurred and the particles detached. Filtration efficiency, α, was shown to a function of both ionic concentration of the liquid medium and flow speed, consistent with a phenomenological model based on the classical DLVO theory. The results elucidates the underlying physics of filtration. [ABSTRACT FROM AUTHOR]