Hydrogen storage in Mg: A most promising material

Life expectancy in most countries has been increasing continually over the several few decades thanks to significant improvements in medicine, public health, as well as personal and environmental hygiene. However, increased life expectancy combined with falling birth rates are expected to engender a large aging demographic in the near future that would impose significant burdens on the socio-economic structure of these countries. Therefore, it is essential to develop cost-effective, easy-to-use systems for the sake of elderly healthcare and well-being. Remote health monitoring, based on non-invasive and wearable sensors, actuators and modern communication and information technologies offers an efficient and cost-effective solution that allows the elderly to continue to live in their comfortable home environment instead of expensive healthcare facilities. These systems will also allow healthcare personnel to monitor important physiological signs of their patients in real time, assess health conditions and provide feedback from distant facilities. In this paper, we have presented and compared several low-cost and non-invasive health and activity monitoring systems that were reported in recent years. A survey on textile-based sensors that can potentially be used in wearable systems is also presented. Finally, compatibility of several communication technologies as well as future perspectives and research challenges in remote monitoring systems will be discussed.

Wearable Sensors for Remote Health Monitoring.

One-dimensional coordination polymers: applications to material science

▪ Abstract Metal-hydrogen (M-H) systems are interesting from both a theoretical and a practical point of view. M-H systems are utilized for energy-storage systems, in sensor applications, and in catalysis. These systems are often exploited as models for studying basic material properties, especially when the size of these systems is small and nonbulk-like contributions become dominant. Surfaces, nanocrystals, vacancy- and dislocation-rich materials, thin films, multilayers, and clusters as systems of major interest are addressed in this review. We show that the hydrogen solubility of M-H systems is strongly affected by the morphology and microstructure of and the stress between regions of different hydrogen concentration. For small-sized systems, surface- or interface-related sites become important and change the overall solubility as well as the phase boundaries of M-H systems. In thin films deposited on stiff substrates, compressive stresses evolve during hydrogen loading because the films are effective...

HYDROGEN IN METALS: Microstructural Aspects

Hydrogen storage alloys are of particular interest as a novel group in functional materials owing to their potential and practical applications in Ni/MH rechargeable batteries. This review is devoted to the specific alloy families developed for high-energy and high-power Ni/MH batteries in the last decades, especially for EV, HEV and PHEV applications. The scope of the work encompasses principles of Ni/MH batteries, electrochemical hydrogen storage thermodynamics and kinetics, prerequisites for hydrogen storage electrode alloys and recent advances in hydrogen storage electrode alloys. Rare earth AB5-type alloys, Ti- and Zr-based AB2-type alloys, Mg-based amorphous/nanocrystalline alloys, rare earth-Mg–Ni-based alloys and Ti–V-based alloys are highlighted. Additionally, the challenges met in developing advanced hydrogen storage alloys for Ni/MH rechargeable batteries are pointed out and some research directions are suggested.

Advanced hydrogen storage alloys for Ni/MH rechargeable batteries

We present the concept of the Vitality Bracelet, a wrist-worn device that helps users in bringing more balance in their daily life, especially a balance between stressful and relaxing situations. On the one hand, the Vitality Bracelet comprises the measurement of your skin conductance, reflecting the current level of arousal of your autonomic nervous system. These skin conductance measurements are analyzed in real-time to give an indication of upcoming tension, but they could also be recorded and visualized to present an overview of the daily or weekly tension patterns. On the other hand, the Vitality Bracelet offers paced breathing exercises, supporting instant relaxation as well as general health and vitality on the long run. This chapter describes the design, development and a first evaluation of the Vitality Bracelet concept.

The Vitality Bracelet: Bringing Balance to Your Life with Psychophysiological Measurements

Disclosed is a hydrogen storage material comprising a magnesium hydride. Said magnesium is stabilized in the fluorite structure. Preferably, the magnesium is at least partly substituted by an element such that the magnesium hydride is stabilized in the fluorite structure. In an advantageous embodiment, the hydrogen storage material also comprises a catalytically active material. Furthermore, an electrochemically active material, as well as an electrochemical cell comprising the above hydrogen storage material are disclosed.

Hydrogen storage material with high storage capacity

The invention relates to powering of an electric circuit (110, 206), and in particular to powering of the electric circuit using mechanical impact or sudden mechanical shock. A device, system and method are disclosed where mechanical impact is converted into electrical energy. In order e.g. to decrease complexity and increase the efficiency of how to provide energy for e.g. portable devices and to increase the amount of energy provided with alternative energy sources such as mechanical impact, a device, system and method using certain shapes, construction and method is provided using a first material (104, 112) and a piezoelectric material (106). In particular, e.g. at least a part of a surface (116) of the device is an impact part suited for a mechanical impact from which the piezoelectric material (106) generates electrical energy. The invention is particularly suited for a ball (102) or electronic systems like a mobile phone (202).

Powering an electric circuit using mechanical impact

In order to find a stress indicator that can be used to monitor stress with wearables, we compare the almost instantaneous effects of psychological stress on skin conductance, with the effects on the stress hormone cortisol, peaking about 20-30 min later. We modelled this relation deploying a convolution of the height of the skin conductance peaks with the cortisol stress response curve, and used it to determine a skin conductance-derived estimate of stress-induced cortisol. We then conducted a first experiment to validate this model, comparing the stress-induced cortisol estimates with cortisol as measured in saliva samples. Participants (N=46) completed stressful, boring, and performance tasks in a controlled laboratory setting. Salivary cortisol samples were taken at regular moments. Based upon the pattern of measured salivary cortisol before and after the performed stressful task we divided subjects in high-cortisol responders and low-cortisol responders. For both groups, we found substantial correlations between the skin conductance-based stress-induced cortisol estimates and the measured salivary cortisol. In addition, the (Fisher-corrected) mean within-participant correlation between these variables was found to be 0.48 which proved to be significantly different from zero. These findings support the use of the skin conductance-based stress-induced cortisol estimates as a stress indicator reflecting in-body cortisol levels.

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Deriving a Cortisol-Related Stress Indicator From Wearable Skin Conductance Measurements: Quantitative Model & Experimental Validation

Disclosed is a hydrogen storage material comprising a magnesium-containing intermetallic compound which can form a hydride with hydrogen. The intermetallic compound comprises an alloy of magnesium and a trivalent metal selected from the group of Sc, Y, La and the rare earth elements. Preferably, the intermetallic compound comprises a scandium-magnesium alloy. In an advantageous embodiment, the hydrogen storage material also comprises a catalytically active material. Furthermore, an electrochemically active material, as well as an electrochemical cell comprising the above hydrogen storage material are disclosed.

Martin Ouwerkerk

Papers

The Vitality Bracelet: Bringing Balance to Your Life with Psychophysiological Measurements

Hydrogen storage material with high storage capacity

Powering an electric circuit using mechanical impact

Deriving a Cortisol-Related Stress Indicator From Wearable Skin Conductance Measurements: Quantitative Model & Experimental Validation

Metal hydride battery material with high storage capacity