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Intumescent coatings employ the heat barrier effect of an expanded char in the fire protection of the underlying substrates. The effectiveness of an intumescent system is dependent on the strength and ability of the char to remain intact upon exposure to fire. Many approaches have been employed to measure the strength of the intumescent char, but there still remains the need for an established standard procedure. In the present study, the compressive strengths of reinforced and unreinforced intumescent chars are evaluated using the compression test for cellular materials (ASTM 1162 00). This standard procedure enabled easy evaluation of compressive strength by employing the principle of deformation force as a function of the axial displacement of char under an active load by using the common universal tensile testing machine. The force–deformation graph revealed an exponentially increasing curve with two distinct regions, an initial region of low force to high deformation representing the collapse of the cellular pores and a high-force–low-deformation region attributed to the bulk mass effect of the compressed char. The results showed that the force needed to compress a bauxite residue-reinforced char to 10% deformation increased by 59%, while the compression strength increased by 13.08% over the control char.

Vitreous enamels represent a class of coatings with different technological properties, mainly appreciated for the protection they guarantee to the covered substrates. This review introduces enamel coatings, describing their production technologies and presenting the main properties affecting the enamel’s durability. Firstly, this review article introduces the most important studies regarding the improvement in abrasion resistance, highlighting both successes and failures. Afterward, the work reveals an outlook about the resistance to chemicals, underlining the good resistance of enamels toward acidic chemicals and discussing the results of studies aimed to improve their performances toward alkaline solutions. This review also considers the corrosion protection property of enamels, highlighting the high barrier effect they provide against the absorption of aggressive substances toward metal substrates. Finally, new perspectives and possible future research paths are presented, being aware that this kind of coating offers both good product protection and functional integrity over time.

In January 2012, a serious accident polluted the Longjiang River with high concentrations of cadmium (Cd) and other concomitant metals and metalloids in the water. After emergency treatment (i.e., the addition of coagulants), these metals and metalloids were transferred from the water into the sediment through precipitation of the flocculent materials produced. In this study, the long-term distribution of six metals and metalloids in the sediment of the Longjiang River was investigated and their ecological risks were assessed. Approximately 1 year after the accident (i.e., late 2012), the average Cd content in the sediment of the affected sites decreased to 25.6 ± 19.5 mg/kg, which was 8 times higher than that of 3.16 ± 3.18 mg/kg in the upstream reference sites. In 2016 and 2017, the average Cd content in the sediment of the affected sites further decreased to 4.91 ± 2.23 and 6.27 ± 4.27 mg/kg, respectively. Compared with late 2012, the amounts of Zn, Pb, and Cu obviously decreased in 2016 and 2017, whereas there were no obvious differences in the As and Hg amounts during 3 years considered. Among metals and metalloids, the average contribution of Cd to the potential ecological risk index (RI) was 90%, 69%, and 70% in the affected areas in 2012, 2016, and 2017, respectively, suggesting that Cd was the most important factor affecting the ecological risk of metals in the Longjiang River. It should be noted that the average contribution of Hg to RI in the affected areas increased from 8% in 2012 to 25% and 23% in 2016 and 2017, respectively. The sequence of contribution of six elements was Cd > Hg > As>Pb > Cu ≈ Zn. A high ecological risk of metals and metalloids was found in the sediments of two reservoirs, probably owing to the barrier effect of the dam. This study will be useful for the environmental management of rivers affected by accidental pollution of metals and metalloids.

In this study, we fabricated and characterized nanometric chitosan (Cs)/laponite (La) nanocomposite nanogels for controlled drug delivery applications. Cs and Cs/La nanocomposite nanogels were formed by ionic gelation method using tripolyphosphate. The release of honey as a model drug was monitored using a blood glucose meter. The results of dynamic light scattering and field emission scanning electron microscopy demonstrated that in the wet state, the mean particle size of nanogels were 133 nm and 118 nm for Cs nanogels and Cs/La nanocomposite nanogels, moderately reducing to 32 nm and 95 nm at dried state, respectively. X-ray diffraction analysis confirmed exfoliated morphology for nanocomposite nanogels. Although honey loading increased the size of the nanogels, it had no effect on the morphology of nanocomposite nanogels. The loading efficiency and loading capacity of encapsulation decreased in nanocomposite nanogels. The honey release profile of nanocomposite nanogels began with a burst release, and showed lower values compared to Cs nanogels during the first hour. Our results corroborated to the higher cross-linking density and barrier effect of La in nanocomposite nanogels.

Small-particle interlayers (lenticles) show some characteristic hydraulic properties and can affect the movement of unsaturated water. In this study, we developed a novel online capillary-water-absorption monitoring device and conducted three groups of comparison tests to simulate lenticle positions and thicknesses with respect to the capillary rise. The results show that the characteristic wetting front exhibits a fast rise in the early stage, a slow rise in the middle stage, and stability in the later stage. The motion of the capillary water in the lenticle is mainly transversal, with the upward curve being “flat,” and the longer is “flat,” the longer is the time needed for the water to move. The interlayer can form a capillary stagnation zone with moisture content close to saturation. The high interlayer may form a discontinuous corrugated capillary zone. Thus, when the wetting front reaches the “coarse-grain (lower)-fine-grain (upper)” interface, the “anti-capillary barrier effect” results in more moisture in the upper layer. Thus, when the wetting front of the capillary water reaches the “fine-grain (upper)-coarse-grain (lower)” interface, the “capillary barrier effect” causes the moisture content of the upper tailings to decreases sharply because of the horizontal movement of the water in the fine medium. It is clear that the presence of lenticles can retard the rise of capillary water by storing water.

Based on the discovery of the "natural orange soil layer" in the wall foundation of the Ming Great Wall in Huangzhong County, Xining City, northwest China, this paper reveals the mechanism behind the barrier effect of this layer on the salinity deterioration through the combination of qualitative judgment and quantitative testing. Based on this mechanism, the conventional lime soil was improved by adding modified polyvinyl alcohol as the cementing agent and fly ash, thereby generating a modified cushion material. Indoor tests of freeze-thaw and temperature-humidity cycles for the modified cushion material were then conducted alongside field tests of rammed restorations in the basal sapping zone with and without the modified cushion. The test results show that the modified cushion materials have excellent durability and act as a substantial barrier to salinity deterioration. The research results provide a new approach to repairing the basal sapping of earthen sites.

Blueberry is rich in anthocyanins, but accounting for 98.2% of the total anthocyanins are in blueberry peel and difficult to release, due to the barrier effect of the cell wall, and the oxidation of polyphenol oxidase also lead to anthocyanins loss. The blanching has a desired effect on the blueberry cell wall and polyphenol oxidase. Therefore, the influences of blanching were studied. The results indicated that the total anthocyanin content of the pulp from the whole blueberry blanching was 1.3 times higher than that of the crushed pulp blanching, and the anthocyanin content obtained from the steam blanching was 0.19 mg/100 g more than the boiling water; the maximum value of 125.35 mg/100 g was reached at 2 min of steam blanching, and the polyphenol oxidase activity was reduced to less than 10%, steam blanching showed a good effect on anthocyanins extraction. Based on the optimal blanching condition, the pulp from blanched blueberries was less red and more blue than the non-blanched, due to the more of malvidin-glycosides and the addition of delphinidin-glycosides and petunidin-glycosides; the retention rate remained at 82% and the degradation rate remained around 1.09 after 40 days. This study could be proposed to apply on the blueberry pulp production for improving the anthocyanins extraction rate and stability.

This paper aims to study the emptying barrier effect on the dangers caused by hydrocarbon liquids. For this work, the case study was a storage tank filled with benzene and the effect was studied by combination of event tree method ALOHA software and static analysis of SOLIDWORKS software. As a result, an increase in the safety ratio was observed with the event tree method. ALOHA modeling showed a decrease in the danger zones with each emptying rate. Finally, the static study showed that the danger applied to the tank decreased. This study presents the importance of the drain barrier in hydrocarbon plants on several levels: safety, environmental and goods (tank).

The influence of mountain ranges on broad-front bird migration has been investigated for several decades. However, almost all the studies have focused on flight behaviour, and have rarely considered the quantitative effect of mountain ranges as a barrier. The present study investigates the spatial and temporal pattern of autumnal bird migration across the eastern part of the Alpine Arc (Austria). Migration intensity was recorded continuously using two dedicated bird radar systems during a full autumn migration season. One radar was located to the north in the Alpine Foreland region for the whole observation period, serving as a reference for the number of birds approaching the Alps. The second radar was moved between four locations across the Alps, operating for 21–26 days at each site. Our findings clearly show that topography significantly influences the spatial distribution of bird migration. Most birds flew lower than the main ridges, with only a small proportion detected above such altitudes (~ 3000 m above sea level). The daily pattern of migration was similar across sites, and there was no accumulation of birds (“Zugstau”) in front of the Eastern Alps. At only one of the inner-Alpine sites did the day-to-day pattern of migration intensities differ considerably from the pattern in the foreland of the Alps. This may be influenced by the wind conditions, causing birds to enter valleys of different geographic orientation. At a large scale, we did not find any evidence of a major barrier effect. In contrast to the south-west oriented central part of the Alpine Arc, where birds concentrate along the mountain ranges, the flux of autumnal bird migration appears to flow over and through the nearly perpendicularly oriented (with respect to their migratory direction) Eastern Alps. This demonstrates how the influence of mountain ranges as barriers depends on their spatial context.

There is a lack of research on the mechanisms by which isolation piles affect displacements in deep soil layers and the use of isolation piles to control the displacement and deformation of the existing tunnels adjacent to deep excavations. This paper examines a large, deep excavation project in which isolation piles were used to protect a nearby existing tunnel. A finite-element model that considers the small-strain characteristics of the soil was used to simulate this project. After the numerical model is verified, it is used in a parametric analysis of the mechanisms by which isolation piles control the displacement of deep soil layers and the deformation of tunnels near excavations. The results show that isolation piles have both a barrier effect and a traction effect on the surrounding soil and adjacent tunnels. When the traction effect is larger, isolation piles can exacerbate the horizontal displacement of the soil and tunnel within a certain depth range and actually increase tunnel deformation. Burying the isolation piles reduces this traction effect and improves their ability to isolate tunnels from displacement. All else being equal, isolation piles more efficiently control deformation if they are near the tunnel.

The insulating oil performance could be enhanced in high-voltage apparatus using barriers. The importance of the barrier in increasing the dielectric strength of the insulating oils in order to reduce the oil failure stresses had not been sufficiently studied. In this paper, the effects of the barrier variables on the insulation performance of the transformer oil for point-plate and plate-plate gaps were demonstrated. These variables are: gap space (d), the barrier location relative to the high-voltage electrode (a / d) %, barrier diameter (D), barrier thickness (e), electrode configurations (EC), the presence of contaminating particles, the weight of the contaminating particles (W) and the temperature of the insulating oil (T). The statistical t test was used to explain whether the effect of these parameters was significant or not. Furthermore, the above-mentioned variables were used as training variables to construct the prediction model of oil breakdown voltage considering barrier effect based on the artificial neural networks (ANN). The ANN model was developed based on the results from experimental works. Therefore, 784 samples were used as training data set and other 25 samples were taken as testing and validating samples. The results explained that the prediction ANN model had a high ability to expect the breakdown voltage for other different experiment cases. The average errors of the training and testing samples were 1.6%, and 2.66%, respectively. Therefore, the prediction accuracy could be considered as 98.4% for training and 97.34% for testing.

Implant-related infections (IRIs) which led to a large amount of medical expenditure were caused by bacteria and fungi that involve the implants in the operation or in ward. Traditional treatments of IRIs were comprised of repeated radical debridement, replacement of internal fixators, and intravenous antibiotics. It needed a long time and numbers of surgeries to cure, which meant a catastrophe to patients. So how to prevent it was more important than to cure it. As an excellent local release system, coating is a good idea by its local drug infusion and barrier effect on resisting biofilms which were the main cause of IRIs. So in this review, materials used for coatings and evidences of prevention were elaborated.

The European Journal of Wildlife Research introduces a new Topical Collection focused on Road Ecology. This Topical Collection aims to be a useful tool for the development of generalized principles and applications concerning wildlife-related aspects of Road Ecology. Submissions exploring new or lesser-known costs and potential benefits for wildlife coexisting with road networks are encouraged., MD was supported by a Juan de la Cierva Formación post-doctoral grant, FA by an FCT (Fundação para a Ciência e a Tecnologia) post-doctoral grant, MF by a University of Molise grant for PhD stays in foreign countries, and RB by a University of Alcalá post-doctoral grant.

From the analyses of the satellite altimeter Maps of Sea Level Anomaly (MSLA) data, tidal gauge sea level data and historical sea level data, this paper investigates the long-term sea level variability in the East China Sea (ECS). Based on the correlation analysis, we calculate the correlation coefficient between tidal gauge and the closest MSLA grid point, then generate the map of correlation coefficient of the entire ECS. The results show that the satellite altimeter MSLA data is effective to observe coastal sea level variability. An important finding is that from map of correlation coefficient we can identify the Kuroshio. The existence of Kuroshio decreases the correlation between coastal and the Pacific sea level. Kurishio likes a barrier or a wall, which blocks the effect of the Pacific and the global change. Moreover, coastal sea level in the ECS is mainly associated with local systems rather than global change. In order to calculate the long-term sea level variability trend, the empirical mode decomposition (EMD) method is applied to derive the trend on each MSLA grid point in the entire ECS. According to the 2-D distribution of the trend and rising rate, the sea level on the right side of the axis of Kuroshio rise faster than in its left side. This result supports the barrier effect of Kuroshio in the ECS. For the entire ECS, the average sea level rose 45.0 mm between 1993 and 2010, with a rising rate of (2.5±0.4) mm/a which is slower than global average. The relatively slower sea level rising rate further proves that sea level rise in the ECS has less response to global change due to its own local system effect.

Internal bags for packaging dry foods into boxes of recycled paperboard, collected in Dresden and Zurich in June 2013, were investigated with regard to the layer composition and the barrier efficiency against substances migrating from the recycled fibers. The layers were identified by microtome cuts and Fourier transform infrared spectroscopy, often after wet-chemical separation of the layers. The barrier efficiency was tested with five surrogate substances and classified between 1 and 5, with class 1 having no significant barrier effect, 4 being a virtually tight barrier consisting of polymeric material and 5 including an aluminum foil. Merely 17 of the 87 bags (20 %) consisted of paper or polyethylene that constituted insignificant barriers. Bags of oriented polypropylene, substantially reducing migration (class 2), were encountered in 32 % of the packs; those with more efficient, but still incomplete barriers (class 3) in 16 % and virtually tight barriers (classes 4 and 5) in 32 % of the products. This is a strong move toward efficient barriers compared to the findings in 2010. Efficient or tight barriers were found for nearly all food types, which suggests that there are no important technical obstacles against the inclusion of a barrier layer into all bags to protect the food against contamination from the recycled paper board.

The resistive switching characteristics of Au/p-NiO/n-SrTiO3(STO)/Pt memory cells are investigated. Two types of bipolar switching with opposite polarity coexist in the cell and can be repeatedly adjusted by the electroforming polarity. The conduction mechanisms of low resistance and high resistance states are dominated by electron tunneling and interface barrier effect, respectively. The impact of electroforming polarity on the switching mechanism and the distribution of defects are discussed. The results indicate that these two types of switching originate from a variation of interface barrier respectively at the NiO/STO p–n junction and STO/Pt Schottky contact.

The change in the compositions of thermal barrier and antioxidant coatings for C-SiC composite materials was examined. Data are reported on the compositions and properties of bi-, tri-, and multilayer coatings. The mechanism of the barrier effect of several compositions is elucidated. The prospects for use of the new compositions of barrier coatings for increasing the temperature of use of the composite materials are demonstrated.

After-cataract is the most common complication in cataract surgery. Implementing a sharp posterior optic edge has, together with improved cortical aspiration, drastically reduced its rate. The impact of optic design and material has been systematically studied in detail in Vienna in a series of prospectively randomized intra-individual comparison studies using objective evaluation methods. Circular rhexis-optic overlap is essential for the durability of the posterior sharp optic edge barrier effect. Using haptics with a capsular bag design and a slim junction to the optic enhanced it further. The use of fibrosis-inducing optic materials has been shown to prolong the barrier effect, which was decreased after anterior capsule polishing. Although the incidence of clinically significant after-cataract has been significantly reduced by these conventional measures, it still cannot be completely avoided.

A design procedure is proposed to minimize water infiltration into landfills by optimizing the water diversion length of inclined covers with capillary barrier effect (CCBE). This design procedure is based on a conceptual, mathematical and numerical approach and aims at selecting materials and optimizing layer thickness. Selection among candidate materials is made based on their hydraulic conductivity functions and on a threshold infiltration rate imposed on the designer. The capillary break layer (CBL; bottom layer) is characterized by a weak capillarity, while the moisture retention layer (MRL; upper layer) is characterized by a compromise between strong capillarity and high hydraulic conductivity. The thickness of the CBL corresponds to the height where suction reaches its maximum value for a given infiltration rate. This height can be calculated using the Kisch [Geotechnique9 (1959)] model. The optimal thickness of the MRL is determined by applying an adaptation of the Ross [Water Resources Research26 (1990)] model. The results obtained using the proposed design procedure were compared to those obtained from numerical simulations performed using a finite element unsaturated seepage software. The procedure was applied for two cover systems; one where deinking by-products (DBP) were used as MRL and sand as CBL and another where sand was used as MRL and gravel as CBL. Using this procedure, it has been shown that an infiltration control system composed of thin layers of sand over gravel is highly efficient in terms of diversion length and that its efficiency can be enhanced by placing a hydraulic barrier – such as a layer of DBP – above the MRL.

Virtual negotiations are expected to differ from face-to-face negotiations in terms of both negotiator behavior and outcomes. Nonetheless, competing theories and mixed results characterize this literature. This paper meta-analytically reviews studies that compared face-to-face negotiation with virtual negotiation (e.g., audio, email/text, video-conferencing). Competing predictions from psychological distance theory and the barrier effect perspective were tested. Overall, results supported the psychological distance theory in that face-to-face negotiations were less hostile and resulted in higher profit than virtual negotiations. Three moderators (negotiation mode, anonymity in virtual negotiation, and further interaction within the experiment) were hypothesized to impact virtual negotiation. While some moderators were significant, they did not completely account for findings across all studies. Results and discussion provide a note of caution for individuals embracing e-business and conducting Internet negotiations as well as suggestions for future research.

The effect of the nature of dislocation density distribution through the thickness of a hardened layer on diffusion processes which occur in friction pairs is studied. This phenomenon is explained on the basis of existing ideas about the dislocation structure of material. 4 refs., 3 figs.

The effect of various barrier materials on the microstructure of electroplated Copper films was investigated. Analysis of the Cu was performed at the as-deposited, room temperature stabilized, and annealed states. It shows that the barrier material can have a dramatic effect on the properties of electroplated Cu.

The charge collection efficiency of a diode with a retrograde well was estimated using focused ion beam irradiation at 400 keV and 2 MeV. The retrograde well was found to effectively suppress a collection of charge carriers created by energetic particles. The charge collection efficiency of the diode with the retrograde well was ~ 25 % lower than that with the conventional well when 400 keV ~ 2 MeV protons were irradiated normal to diodes. This result was in good agreement with device simulation.

We describe techniques of reliable metallization in InP-based systems for application to discrete and opto-electronic integrated circuits (OEIC’s). Strong metallurgical interaction between Au and InP-based compounds can cause serious contact degradation in light emitting diodes (LED’s). By analyzing this interaction in detail, an improved thin Au/Zn/Au p-contact technique has been developed. The results are compared with Pt/Ti contacts, and it has shown that both provide sufficient reliability under temperature and current stresses in LED’s. We then describe a metallization technique for flip-chip bonding of opto-electronic devices on other semiconductor chips for OEIC applications. An acceptable reaction barrier effect of Pt in AuSn/Pt/Ti metallization structure has been demonstrated and this structure has been used for a high-reliability, flip-chip integrated GalnAs/InP PIN photodiode/GaAs amplifier receiver circuit. We also discuss requirements for metallization for future monolithic OEIC’s by taking up an example of metal-semiconductor-metal photodiodes in InP-based systems.

We consider the perturbation of a stratified rotating fluid due to the crossing of a mountain ridge. The behaviour of the solutions is examined in the primitive Navier-Stokes equations in linear form studied by Queney. We produce the Green's functions of the problem at ground level at any distance from the perturbing ridge; in this sense it is an extension of the theory presented by Pierrehumbert. Furthermore, we discuss the relative contribution of the different terms and we examine the behaviour of small-scale waves with altitude. This work is also relevant for the parametrization of the subgrid physical effect in large numerical models, like the barrier effect of the Alps or the Rocky Mountains.

1. The effect of substituents on the frequencies and intensities of Raman spectrum lines has been studied in the compounds X3M-CH2-CH=CH2, where M=Si, Ge, and X=F, Cl, Br. 2. Whereas the frequencies increase in the normal electronegativity series CH3 < Br < Cl < F, the intensities increase in the series F < Cl < CH3 < Br. 3. The concept of a “barrier effect” at the silicon and germanium atoms in the compounds studied has been refined.