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Flexible packaging materials consisting of several layers of very dissimilar materials are currently considered for replacement by multilayer polyolefin films as well as functional flexible paper materials to improve recyclability. Such materials however lead to new challenges in processing on existing packaging machinery. This paper focuses on the sealing process of such materials, especially looking at pillow pouches and the challenges occurring at the junction between cross and fin seals where the total thickness jumps from two to four layers. It is shown that the application of conventional machinery and sealing tools does not lead to a gastight seal within the operational sealing window of such materials. The origin of the permanent failure is the lack of material fraction capable to flow as a viscous melt into the gap at the fin seal. The limited compressibility of the nonmelting materials and their bending stiffness tend to increase the gap. In case of paper, a flexible sealing jaw, equipped with an elastic insert, enables a focused application of pressure at the layer jump of a poorly compressible material. This results in clearly improved gas tightness of all selected materials in the range of the used test methods (leak size 10 mm). The leakage rate of papers was reduced from 3-4 mbar·l/s with rigid tools to 1 mbar·l/s with flexible tools. The leakage of 2 mbar·l/s with OPP/CPP material could be prevented and no leaks were detected. With OPP/PE, leak‐proof results were obtain within reduced temperature at 140°, which is near the level of acceptable seal quality with low shrinkage effect.

In triaxial test, a rubber membrane encloses the specimen. The membrane is specifically thin to a thickness of no influence on the test results. However, testing coarse-grained materials in triaxial test might be challenging due to the occurrence of membrane punching. In trial tests, the angular aggregate easily punches the membrane. A technique was explored to mitigate membrane punching due to sharp edges of angular materials. One method has filter paper inserted between two membranes and another method has aluminium foil instead of filter paper. The use of filter paper and aluminium foil as insert materials is successful in preventing the membrane punching. Consequently, the filter paper is not contributing to additional resistance when used as protection between two membranes as compared to aluminium foil. This paper investigates the performance of the protection materials by experiments. Essentially, the filter paper had no significant effect on test results; this fact was verified through numerical modelling and comparative tests by using rounded particles material.

Reflective cracking is frequently reported as the most common distress affecting resurfaced pavements. An asphalt rubber membrane interlayer (ARMI) approach has been traditionally used in Florida to mitigate reflective cracking. However, recent field evidence has raised doubts about the effectiveness of the ARMI when placed near the surface, indicating questionable benefits to reflective cracking and increased instability rutting potential. The main purpose of this research was to develop guidelines for an effective alternative to the ARMI for mitigation of near-surface reflective cracking in overlays on asphalt pavement. Fourteen interlayer mixtures, covering three aggregate types widely used in Florida, and two nominal maximum aggregate sizes (NMAS) were designed according to key characteristics identified for mitigation of reflective cracking, that is, sufficient gradation coarseness and high asphalt content. The dominant aggregate size range—interstitial component (DASR-IC) model was used for the design of all mixture gradations. A composite specimen interface cracking (CSIC) test was employed to evaluate reflective cracking performance of interlayer systems. In addition, asphalt pavement analyzer (APA) tests were performed to determine whether the interlayer mixtures had sufficient rutting resistance. The results indicated that interlayer mixtures designed with lower compaction effort, reduced design air voids, and coarser gradation led to more cost-effective fracture-tolerant and shear-resistant (FTSR) interlayers. Therefore, preliminary design guidelines including minimum effective film thickness and maximum DASR porosity requirements were proposed for 9.5-mm NMAS (35 µm and 50%) and 4.75-mm NMAS FTSR mixtures (20 µm and 60%) to mitigate near-surface reflective cracking.

This paper evaluates the thermal behaviour of recycled rubber membranes from End of Life Tyres (ELTs) reinforced with steel wool fibres, and their potential use as solar collectors. The thermophysical and heating properties of the rubber membranes with different steel wool fibre contents were evaluated. The thermal performance of a solar collector prototype manufactured with these membranes was also evaluated. It was proven that the addition of metallic fibres can increase the amount of heat absorbed and the heating rate in the membranes. However, fibre addition over 0.5%/v does not contribute to an increase in the temperature reached. A solar collector prototype fabricated with rubber membranes with 0.5%/v of fibres can transmit the heat absorbed by the membrane to the water, reaching a temperature of 45 °C, thus demonstrating that it can be used as new sustainable construction material for energy harvesting applications.

The effects of barreling of a particulate compact specimen caused by the end restraint and rubber membrane during a conventional triaxial test on the yield surface of a pressure-dependent and linearly elastic-perfectly plastic constitutive model are investigated via finite element analysis. The combined influence of the end restraint and rubber membrane results in barreling of the specimen which causes artifacts in the experimental deviator stress vs. strain curve determined in the triaxial test. Values of the shear-failure deviator strengths at varying confinement pressures have been modified to exclude the artifact caused by the specimen barreling, followed by the refinement of the yield-surface parameter set of the constitutive model. The refined set predicts the experimental curve better than the unrefined one does.

Balloonygen, an extended tabletop display embedded with a balloon-like deformable spherical screen, is a display that can seamlessly expose a spherical screen for three-dimensional contents, such as omnidirectional images, in a conventional flat display. By continuously morphing between a two-dimensional shape called tabletop and a three-dimensional shape called sphere, we render the benefits of a flat display and a spherical display to coexist and propose a smoother approach for information sharing. Balloonygen dynamically provides an optimal way to display the contents by inflating the rubber membrane installed at the center of a tabletop display and morphing between the two- and three-dimensional shapes. In this study, by prototyping and designing the application scenario, we discuss the advantages and disadvantages of this display and possible interactions involved.

Dielectric Elastomer Transducers (DETs) are solid-state electrostatic devices with variable capacitance that can convert electrical energy into mechanical energy and vice-versa. Recent theoretical and experimental studies demonstrated that DETs made of materials like silicone elastomer and natural rubber can operate at very high energy densities. Practical applicability of DETs is strongly affected by their reliability and lifetime, which depend on the maximum strain and electrical loads that are cyclically applied on such devices. To date, very little knowledge and experimental results are available on the subject. In this context, this paper reports on an extensive lifetime assessment campaign conducted on frame-stretched circular DET specimens made of a commercial styrenic rubber membrane subjected to cyclic electrical loading.

A multi-layer low-frequency broadband membrane-type acoustic metamaterial sound isolator were investigated. It is a multi-layer “plate-membrane-plate-membrane-plate” structure composed of light round whole plate and elastic rubber membrane. By simulation analysis towards single layer and multi-layer structure as well as different parameters that affect multi-layer structure, the corresponding acoustic insulation index of each frequency band was obtained. By comparison of the acoustic insulation curves under different circumstances, the acoustic insulation properties under different circumstances can be obtained by direct-view. The results of simulation analysis can enrich the research of multilayered metamaterials to a certain extent.

Performance textiles that protect human from different threats and dangers from environment are in high demand, and the advancement in functionalization technology together with employing advanced materials have made this an area of research focus. In this work, silicone rubber and environmentally friendly fluoropolymers have been employed to explore superomniphobic surface on cotton fabrics without compromising comfort much. It has been found that a cross-linked network between the rubber membrane and the fluoropolymers has been formed. The surface appearance, morphology, handle, thickness and chemical components of the surface of cotton fabrics have been changed. The coated fabrics showed resistance to water, aqueous liquid, oil, chemicals and soil. The comfort of the coated fabrics is different to uncoated cotton fabrics due to the existence of coated layers on the surface of cotton fabrics. This work would benefit the development and design of the next generation of performance textiles with balanced performance and comfort.

In a triaxial test of soil, a specimen in the cell is enclosed by a rubber membrane to separate soil particles from the surrounding water that represents the confining pressure. Upon increasing the confining pressure, this membrane penetrates the voids between the particles of the specimen and cause errors in triaxial test results, these errors lead to changes in shear strength and volume change measurements. Therefore, the results need to be corrected for membrane penetration. This paper emphasizes the importance of correcting triaxial test results for membrane penetration by presenting the influence of membrane penetration on shear strength and volume change measurements. It was concluded that the rubber membrane can produce apparent increase in volume change and shear strength either due to membrane penetration (when the test is at drained condition) or due to membrane compliance (when the test is at undrained condition).

Rubber membranes exhibit a particular nonlinear elastic behaviour known as hyper elasticity. Analysis has been proposed by utilizing the modified strain energy function from Gao’s constitutive model, in order to reveal the mechanical property of rubber membrane containing circular rigid inclusion. Rubber membrane is taken into incompressible materials under axisymmetric stretch, based on finite deformations theory. Stress distribution of different constitutive parameters has been analyzed by deducing the basic governing equation. The effects on membrane deformation by different parameters and the failure reasons of rubber membrane have been discussed, which provides reasonable reference for the design of rubber membrane.

This paper presents a review on the effect of rubber membranes on the measured stress and volume change data during the triaxial tests. In many instants, the error associated due to membrane penetration is measured to be close to the total sample volumetric strains. Hence, in addition to precise measurements, adopting an appropriate correction to the measured data is pivotal. This paper provides a detailed review on the methods used to estimate and reduce the influence of rubber membrane on the measured triaxial test results. The discussion therefore clearly highlights the stiffness, thickness, and diameter of the membrane used, to have significant influence on the measured deviatoric stress and the volume change data. The mean grain size of sample has an equally significant influence on the volume change. The methods in general are limited to test conditions, and therefore, it is practically uncertain to have a generalized correction procedure. Effectively, the outcome from this review work enhances the understanding of the reader towards the effect, methods, and corrections to be considered in triaxial testing due to rubber membrane and membrane penetration effects.

This paper addresses a study of air bubble creation in wastewater treatment system using both computational fluid dynamic (CFD) and experimental techniques. Based on the results found in this work, it was found that the bubble size depends on several factors such as flow rate, inlet pressure and contact angle for rubber membrane. Among these factors, it was found that the flow rate has the largest effect on the bubble size followed by membrane material contact angle. The punch size has a moderate effect on the bubble size while the punch length and punch direction have slight effect on bubble size. Finer bubbles are desired and they provide larger surface area and longer residency time which will improve the standard oxygen transfer.

Most of the existing methods that are used to measure the coefficient of earth pressure at rest (K0) are not suitable for coarse granular soil because of the rubber membrane; therefore, an apparatus to measure the K0 of coarse-grained soil should be developed. The aim of this article is to introduce a new-type apparatus for measuring the K0 of coarse granular soil. A method for correcting the effect of the side wall friction is proposed to ensure test accuracy. To compare it with the conventional water-bag type K0 oedometer, tests on a dry sand using both the new apparatus and the conventional K0 oedometer were performed. Results proved that the newly developed apparatus is more accurate than the water-bag type K0 oedometer. Of importance, some tests of coarse granular soils were taken for application of the apparatus. The results show that the K0 of the coarse granular soil is almost a constant value during the loading steps but changes greatly during the unloading steps. In addition, an equation is proposed to predict K0 changing with the overconsolidation ratio during unloading. The K0 of coarse granular soil decreases when the density increases, and the influence of the gradation on K0 is evident.

The structure and composition analysis of additives are key points of improving the quality and capability of lubricant. In this article, primary additives are separated from lubricant with rubber membrane dialysis, extraction method, column chromatography combined with element analysis, and infrared spectrometry. The result shows the compositions of antioxidant and extreme pressure and antiwear additive.

Summary: Objective: Three experiments (EXP) were conducted to investigate if air contaminated with PRRS virus (Ingelvac PRRS MLV vaccine containing the North American strain) can be sucked into ultrasound machines and then expelled back into an infected (EXP-1) or a clean environment (EXP-3) through the action of ventilation fans, and if covering the machines prevents exhaust expulsion of the virus (EXP-2). Materials and methods: The experimental apparatus basically comprised of a plastic chamber, an ultrasound unit HS 1201, a device that allowed for virus aerosolization and a pipe system that allowed the air to return into the chamber (EXP-1) or to be expelled into the atmosphere (EXP-3), or was blocked by using a rubber membrane (EXP-2). In EXP-1, different virus concentrations were tested (i. e. 104, 105 and 106 TCID50, each concentration in three replicates and two runs). In EXP-2, the highest concentration, i. e. 106 TCID50 was used (three replicates and two runs). EXP-3 immediately followed EXP-2 without introduction of new virus (two runs). Virus exhaust expulsion was monitored by swabbing the pipe system with the swabs being subjected to RT-nPCR and culture. Results: In EXP-1, 106 TCID50 PRRSV, but none of the other concentrations, gave constantly virus-positive results by RT-nPCR. In EXP-2, covering completely prevented virus exhaust expulsion. In EXP-3, two out of eight swabs were positive by RT-nPCR. Cell culture of positive swabs was negative. Conclusion: The study suggests exhaust expulsion of PRRSV through ultrasound machines equipped with a ventilator fan into an infected and a clean environment, but failed to demonstrate infectivity of the expelled virus. Preventing exhaust air expulsion by complete covering prevents the expulsion of the virus.

This paper describes an investigation into the performance and pullout capacity of an inflatable anchor system. The anchor system comprises a hydraulically inflated rubber membrane or packer that may be bored into place and then inflated to provide pullout resistance. A series of scaled physical model tests were used to study the anchor performance and pullout capacity. The model tests were done in a calibration chamber using cohesionless sand and anchors of various length, diameter, embedment depth and inflation pressure. The anchor behaviour during pullout is interpreted using finite element analysis that accounts for non-linear soil behaviour, inflation and subsequent deformation of the inflatable membrane, and anchor-soil interaction. The scaled model tests and interpretations assist with identifying the dominant mechanisms affecting the pullout capacity of inflatable anchor systems.

資料番号: AA0063716012

This article describes the currently operational version of the low-technology wind pump of high efficiency, as presented in [Valdes L-C, Raniriharinosy K. Low technical wind pumping of high efficiency. Renewable Energy 24 (2001) 275–301]. The pump, made entirely of wood and using roller bearings for the rotating links and a rubber membrane for water tightness, is of a more modular conception. Its manufacture is slightly more complicated, but its dimensioning has been greatly simplified, its reliability significantly improved and the use of wind energy optimised.

This paper deals with the problem of the transverse deflection of a natural rubber membrane that is fixed along a circular boundary. Uniaxial experiments were performed in order to characterize the constitutive behaviour of the rubber material in terms of several constitutive models available in the literature. These constitutive models were used to develop computational estimates for the quasi-static load–displacement response of a rigid spherical indentor that deflects the rubber membrane in a controlled fashion and to determine the deflected shape of the membrane at specified load levels. Both axisymmetric and asymmetric deflections of the rubber membrane were investigated. The paper provides a comparison of the experimental results for the membrane deflections with results derived from computational simulations.

The bubble column reactor (BCR) used in Part I was subjected to forced oscillations at high gas rates under jetting conditions. Two piston types were used: a flexible rubber membrane as used in Part I and a modification thereof to cause a more rigid, stiff piston behavior. The mass transfer performance differences between the piston types were quite remarkable, the former yielding peaking with respect to increased frequency and the latter produced monotonic increases up to an asymptote as the frequency was increased. The Benjamin–Ursell stability theory was found useful in tracking regimes of maximum enhancement. © 2005 American Institute of Chemical Engineers AIChE J, 2006

For effective medical treatment, sensors that can find foreign bodies such as tumors in early stage are required. This paper describes a new sensor for foreign body detection utilizing the fact that the property hardness of foreign bodies differs from that of normal tissues. It consists of a balloon probe, which is constructed with a thin rubber membrane inflated with compressed air, and an optical deformation analyzing system. Experiments are carried out using samples in which single hard balls are embedded to model single tumor in soft tissue. It was confirmed that this sensor can detect the existence of the hard ball and can also distinguish the inequality of size and hardness of the ball. Furthermore, experimental results detecting multi-objects showed that this sensor has the ability to detect the existence of multi objects and their relative positions simultaneously. By measuring the consistence of the arm and the abdomen of human body, it is proved that the sensor is also suitable for consistence measurement of human anatomy.

The Mullins effect in the small amplitude transverse vibration of a stretched rubber membrane is investigated. The fundamental frequency, which decreases with increasing softening, is determined for a specific class of stress-softening materials. Analytical relations for the membrane vibration frequency are illustrated graphically for three phenomenological models and two kinds of non-Gaussian molecular network models for rubber elasticity. The results demonstrate the role of the material parameters and, although no experimental data for the vibration of a rubber membrane currently are known, the theoretical predictions are characteristic of the frequency-stretch response reported in vibration experiments on rubber cords.

Cardiovascular disease is one of the leading causes of death in the United States and also a major disease nationwide. Over 700,000 coronary artery bypass graft (CABG) procedures are performed annually all around the world, of which 350,000 are performed in the United States. The use of mechanical stabilizers to isolate and immobilize the surface region of the heart is not without its limitations such as hemodynamic deterioration, and arrythmia induction requiring inotropic support. Consequently, the use of mechanical stabilizers leads to a poor immobilization of the surgical field in spite of significant forces of traction and retraction used with these devices. The primary goal of this research is to develop effective haptic (sense of touch) and visual servoing methods with the long-term goal of eliminating the need for mechanical stabilizers and extracorporeal support for CABG procedures. We present in this paper the results from our initial work in the area of tracking a deformable membrane using vision and providing haptic feedback to the user, based on the visual information through the vision hardware and the material properties of the membrane. In our first experiment, we track the deformation of a rubber membrane in real-time through stereovision while providing haptic feedback to the user interacting with the reconstructed membrane through the PHANToM haptic device. In the second experiment, we verify the ability of our vision system to track a point on a surface undergoing a complex 3D motion.

To estimate the transfer impedance of the respiratory system $$\left( {Z_{{\text{tr}}} } \right)$$ we applied pressure forcing at the mouth from 1 to 24 Hz in eight healthy subjects and used optoelectronic plethysmography (OEP) to measure volume changes of the chest wall and its different compartments: pulmonary rib cage $$\left( {RC_p } \right)$$ abdominal rib cage $$\left( {RC_a } \right)$$ and abdomen (AB). Spectral analysis allowed assessment of input impedance $$\left( {Z_{{\text{in}}} } \right)$$ and total $$\left( {Z_{{\text{tr}}} } \right)$$ and compartmental $$\left( {Z_{\text{p}} } \right),$$ $${Z_{{\text{RC}}_{\text{p}} } ,}$$ and $${Z_{{\text{AB}}} }$$ transfer impedances. As expected, averaged values of $${Z_{{\text{in}}} }$$ and $${Z_{{\text{tr}}} }$$ were similar at low frequencies (

A technique is proposed to predict the gassed power draw of mixed impeller systems as a weighted average of the gassed power draws of the individual impellers. The success of this method requires determining the gassed power draws of the individual impellers in the proper gassed environment. In the case of the upper impellers, this environment is provided by a rubber membrane sparger that distributes the gas evenly over the vessel cross section. Extensive comparisons of experimental gassed power draws of mixed impeller systems with model predictions verify the accuracy of the proposed technique. On propose une technique afin de predire la consommation de puissance en milieu aere de systemes de turbines multiples comme une moyenne ponderee de la consommation de puissance en milieu aere des turbines individuelles. Pour reussir, cette methode necessite qu'on determine les consommations de puissance en milieu aeree des turbines individuelles dans l'environnement d'aeration approprie. Dans le cas des turbines superieures, cet environnement est fourni par un aerateur a membrane de caoutchouc qui distribue le gaz de maniere egale au-dessus de la section transversale du reservoir. Des comparaisons extensives entre les consommations de puisance en milieu aere experimentales des systemes de turbines multiples et des predictions du modele demontrent la precision de la technique proposee.

Self-boring pressuremeter tests are presently used to assess in situ deformation characteristics of sand. To reach the desire testing depth with minimum disturbance, a consistent self-boring procedure is commonly adopted. High lateral stresses developed during insertion of the pressuremeter has led, in the past, to the adoption of a lantern to cover and protect the expandable rubber membrane section of the probe. This note summarizes an investigation of the influence of different lantern designs on the predicted shear modulus of the sand. Distinct steel strip lanterns were used and compared with the standard lantern used in the Camkometer. It is demonstrated that the interstrip friction of the steel lantern can affect the shear modulus from unload–reload loops of the test. The importance of this investigation is viewed as more practical than technical, since steel lanterns are less expensive, quicker, and simpler to construct than the standard Camkometer lantern. Key words: self-boring procedure, lanterns effect, unload–reload, interstrip friction, shear modulus, sand.

In order to generate weak shock waves with repeatability of better than 99%, a shock tube was constructed which, instead of rupturing conventional diaphragms, utilizes 0.5 mm to 1.0 mm thick rubber membrane to separate the driver and driven gases. Sudden leakage of the high-pressure gas which bulged the rubber membrane subsequently drove a weak shock wave into the low-pressure channel within a relatively short formation length. The rubber membrane was operated within its elastic limit and moved very quickly, giving good repeatability. With identical initial conditions for a series of experiments, the scatter of shock Mach number was found to be at most ±0.25% for shock Mach number ranging from Ms=1.02 to 1.55 throughout more than 100 runs.