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[en] Increasing numbers of galleries, museums and archives are including ink jet printed materials into their collections, and therefore displays. There is evidence that the instability of these prints is such that images can suffer deterioration in print quality or in extreme cases, a loss of information over an extended period of time. This is shorter than the period typically required for perceptible deterioration to occur in many other paper-based artworks. The image stability of prints is affected by a number of factors some of which have already been studied. However the role played by the ink solvent in the loss of image quality has yet to be explored. This paper will outline research being undertaken to investigate the effects of solvent content which may increase/promote the loss in image quality of the hard copy prints when stored or displayed under a range of temperature and humidity conditions.
[en] Pressure agglomeration of powders is widely applied in various industries and an increasing interest lies in the identification and description of contact mechanisms between particles, which are responsible for the compaction product properties. In this paper, the design and development of a novel micromanipulation particle tester (MPT) is presented. This device makes it possible to measure the deformation kinetics and resulting adhesion of two individual particles in contact under load, which are strongly influenced by the applied process conditions. The MPT set-up is, therefore, designed to offer a unique control over the process conditions most relevant to the compaction of powders: external stress, dwell or holding time at constant deformation, compression velocity as well as relative humidity and temperature determining the physical state and mechanical characteristics of hygrosensitive amorphous particles. The latter are often part of powder formulations, e.g. in the food industry, and have been used for force and contact-zone development studies with the MPT. The experimental results on the microscale level will deliver valuable quantitative information for an improved tailoring of pressure agglomeration process conditions of bulk solids. (paper)
[en] Present article is devoted to situation in waste storage and influence of wastes on underground waters. At the same time the article shows the results of research works on physical and mechanical properties of wastes and it proves that wastes do not have harmful effect on both underground waters and the environment.
[en] Inversion-based feedforward techniques have been known to deliver accurate tracking performance in the absence of plant parameter uncertainties. Piezoelectric stack actuated nanopositioning platforms are prone to variations in their system parameters such as resonance frequencies, due to changes in operating conditions like ambient temperature, humidity and loading. They also suffer from nonlinear effects of hysteresis, an inherent property of a piezoelectric actuator; charge actuation is applied to reduce the effects of hysteresis. In this work, we propose and test a technique that integrates a suitable feedback controller to reduce the effects of parameter uncertainties with the inversion-based feedforward technique. It is shown experimentally that the combination of damping, feedforward and charge actuation increases the tracking bandwidth of the platform from 310 to 1320 Hz
[en] The corrosion deterioration in metallic structural elements, with the consistent loss of his physical and mechanical properties, is cause by errors in the design or fabrication, that allows the accumulation of humidity and contaminants in the surfaces, or acceleration zones of the corrosion processes, as the bimetalics pairs. The aggressiveness of the environment and the productive processes that develop in industrial installations, causes the apparition of premature failures that engage the edification use. The identification of design errors is the first step in the conservation of these structures. the elimination and made a project adapted to the proper installations conditions, is essential procedures to prolong the edification useful life with an optimum and rational use of the resources that destined for this end. The investigation is about the results obtained in the diagnostic and the conservation of industrial installment, with large exploitation periods, in which existed evidences of failures by corrosion, specifically to the elimination of errors of design. (Author) 12 refs
[en] Electrochemical study on cut edge corrosion of prepainted Zn coated (GI) and 55%Al-Zn coated (GL) steels has been performed in wet-dry cyclic conditions. Maximum width of delaminated polymer coating from the cut edge for GI and GL specimens was evaluated under wet-dry cyclic conditions. The cyclic tests were carried out for 1000 h by changing of relative humidity, where the salt of NaCl was deposited on the specimen every 48 h. The cut edge corrosion test under NaCl deposit indicated that the delamination of the GL specimen progresses at a higher rate than the GI. The electrochemical corrosion monitoring was also performed under condition of alternate exposure to immersion in NaCl solution and drying at 60%RH and 25 .deg. C. On the basis of the results of the delamination tests and electrochemical measurements, the mechanism of cut-edge corrosion for GI and GL were discussed
[en] Recently, the humidity sensors have captivated huge attention for making human life more comfortable and to diagnose several diseases. Here, we reported the excellent humidity responsiveness of V0.5Sn0.5Se2 ternary alloy for human breath monitoring and touchless positioning interface. The resistive sensor based on direct vapour transport grown bulk crystal of V0.5Sn0.5Se2 ternary alloy is fabricated and explored for its static response in different humidity levels ranging from 20 to 90%. The sensor showed excellent dynamic switching characteristics between relative humidity of 20% and 90% with responsivity of 6.78%, response time of 3.2 s and recovery time of 2.3 s. Subsequently, the sensor is exploited for giant responsiveness for human breath monitoring and words recognitions. The sensor exhibited quite distinct response towards different words namely, “Pratik”, “Chetan” and “Mohit”. Besides, novel touch-less positioning interface is explained with respect to humidity variation. Overall, the results advocate development of resistive sensors for intended humidity, biomedical as well as for intelligent touch-less sensing applications.
[en] The swelling of cross-linked polymers of ethynyl-piperidol in the water and assessment of factors which impact on this process was studied. For the investigation were used eight cross-linked polymers of ethynyl vinyl trimethyl piperidol differing on rate of reticulation. The average value of water adsorption for eight cross-linked polymers of ethynyl vinyl trimethyl piperidol depending on relative humidity were defined. The isotherm of water adsorption by cross-linked polymer B 98⁕HCl was constructed.
[en] NPN-type small and medium power switching transistors in 3DK series are used to conduct analyses and studies of accelerating degradation. Through three group studies of accelerating degradation in different temperature–humidity constant stresses, the failure sensitive parameters of transistors are identified and the lifetime of samples is extrapolated from the performance degradation data. Average lifetimes in three common distributions are given, when, combined with the Hallberg–Peck temperature–humidity model, the storage lifetime of transistor samples in the natural storage condition is extrapolated between 10"5–10"7 h. According to its definition, the accelerating factor is 1462 in 100°C/100% relative humidity (RH) stress condition, and 25°C/25% RH stress condition. Finally, the degradation causes of performance parameters of the test samples are analyzed. The findings can provide certain references for the storage reliability of domestic transistors. (semiconductor devices)
[en] The filtration efficiency for nanoparticles down to 1 nm in size through glass fibrous filters was measured using an improved PSM-CNC system. In addition, the effects of relative humidity and particle charge were investigated for various nanoparticle diameters. The results show that the filtration efficiencies were independent of humidity and affected by particle charge in the case of particles below 100 nm in size. For particles smaller than 2 nm, the particle penetrations increased with decreasing particle size. These results suggest that the thermal rebound phenomena would be operative for nanoparticles with diameters below 2 nm, even though it would depend on the states of both the particles and the filter media. These results are particularly important for experimental investigations of the behavior of nanoparticles on a filter