AMORF/NANOYAPILI Mg-ESASLI İNCE FİLMLERİN HİDROJEN DEPOLAMA UYGULAMALARI İÇİN ÇOK ELEMENTLİ KAYNAKLARDAN ÜRETİMİ

A study was carried out for the production of Mg-based amorphous/nanostructured thin films from multi-elemental evaporation sources via thermal evaporation. Sources produced were Mg-Cu, Mg-Cu-Ni, Mg-Cu-Al, Mg-Cu-Al-Ni and all prepared by traditional powder metallurgy routes. The powder compacts in the as-sintered state were made of equilibrium phases and individual elements, but upon deposition, due to interaction in the vapor phase, refined structure yielded amorphous like thin films. The structure further refined by the sorption of hydrogen. The study showed that the powder metallurgy approach is applied with success to deposit amorphous/nanostructured thin films via thermal evaporation, and further implies that if the phase analysis were to be used as an evaluation method for hydrogen sorption characteristics, some other techniques instead of X-ray diffraction analysis have to be consideredBu çalışmada, Mg-esaslı amorf/nanoyapılı ince filmler ısıl buhar çöktürme yoluyla üretilmiştir. Tüm filmler, toz metalurjisi yöntemleri ile hazırlanmış çok elementli kaynakların buharlaştırılması ile elde edilmiştir. Hazırlanan kaynaklar Mg-Cu, Mg-Cu-Ni, Mg-Cu-Al, Mg-Cu-Al-Ni şeklindedir. Üretilen kaynakların, sinterlendikleri sıcaklıktaki denge fazlarını ve serbest halde elementleri içerdikleri görülmüştür. Buharlaştırma sonrası ise sistemdeki fazların büyük oranda zayıflaştığı/amorflaştığı, hidrürlemenin ise incelmeyi daha da fazla artırdığı tespit edilmiştir. Çalışma, önerilen yöntemin ısıl buharlaştırma ile amorf/nanoyapılı film oluşturmaya uygun olduğunu göstermekle birlikte, bu tarz filmlerde, hidrojen depolama davranışının takibinde, X-ışınları kırınımından farklı yöntemlerin kullanılması gerekliliğini ortaya koymaktadır

MDCT Findings of Denim-Sandblasting-Induced Silicosis: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Denim sandblasting is as a novel cause of silicosis in Turkey, with reports of a recent increase in cases and fatal outcomes. We aimed to describe the radiological features of patients exposed to silica during denim sandblasting and define factors related to the development of silicosis.</p> <p>Methods</p> <p>Sixty consecutive men with a history of exposure to silica during denim sandblasting were recruited. All CT examinations were performed using a 64-row multi-detector CT (MDCT). The nodules were qualitatively and semi-quantitatively analyzed by grading nodular profusion (NP) on CT images.</p> <p>Results</p> <p>Silicosis was diagnosed radiologically in 73.3% of patients (44 of 60). The latency period (the time between initial exposure and radiological imaging) and duration of silica exposure was longer in patients diagnosed with silicosis than in those without silicosis (p < 0.05). Nodules were present in all cases with centrilobular type as the commonest (63.6%). All cases of silicosis were clinically classified as accelerated and 11.4% had progressive massive fibrosis (PMF). Mild NP lesions were the most prevalent in all six zones of the lung. The NP score was significantly correlated with the duration of silica exposure, the latency period, presence of PMF, and pleural thickening. Enlarged lymphadenopathy was present in 45.5% of patients.</p> <p>Conclusions</p> <p>The duration of exposure and the latency period are important for development of silicosis in denim sandblasters. MDCT is a useful tool in detecting findings of silicosis in workers who has silica exposure.</p

5G Internet of Things: A survey

© 2018 The existing 4G networks have been widely used in the Internet of Things (IoT) and is continuously evolving to match the needs of the future Internet of Things (IoT) applications. The 5G networks are expected to massive expand today's IoT that can boost cellular operations, IoT security, and network challenges and driving the Internet future to the edge. The existing IoT solutions are facing a number of challenges such as large number of connection of nodes, security, and new standards. This paper reviews the current research state-of-the-art of 5G IoT, key enabling technologies, and main research trends and challenges in 5G IoT

A Survey on Virtualization of Wireless Sensor Networks

Wireless Sensor Networks (WSNs) are gaining tremendous importance thanks to their broad range of commercial applications such as in smart home automation, health-care and industrial automation. In these applications multi-vendor and heterogeneous sensor nodes are deployed. Due to strict administrative control over the specific WSN domains, communication barriers, conflicting goals and the economic interests of different WSN sensor node vendors, it is difficult to introduce a large scale federated WSN. By allowing heterogeneous sensor nodes in WSNs to coexist on a shared physical sensor substrate, virtualization in sensor network may provide flexibility, cost effective solutions, promote diversity, ensure security and increase manageability. This paper surveys the novel approach of using the large scale federated WSN resources in a sensor virtualization environment. Our focus in this paper is to introduce a few design goals, the challenges and opportunities of research in the field of sensor network virtualization as well as to illustrate a current status of research in this field. This paper also presents a wide array of state-of-the art projects related to sensor network virtualization

Securing a wireless sensor network for human tracking: a review of solutions

Currently, wireless sensor networks (WSNs) are formed by devices with limited resources and limited power energy availability. Thanks to their cost effectiveness, flexibility, and ease of deployment, wireless sensor networks have been applied to many scenarios such as industrial, civil, and military applications. For many applications, security is a primary issue, but this produces an extra energy cost. Thus, in real applications, a trade-off is required between the security level and energy consumption. This paper evaluates different security schemes applied to human tracking applications, based on a real-case scenario.Junta de Andalucía P07-TIC-02476Junta de Andalucía TIC-570

Effect of hypoxia-inducible factor-1 alpha expression on survival in patients with metastatic cervical squamous cell carcinoma treated with first-line chemotherapy and bevacizumab

This study addresses the gap in understanding the prognostic relevance of hypoxia-inducible factor-1 alpha (HIF-1 alpha) expression in metastatic cervical squamous cell carcinoma (SCC) patients undergoing anti-vascular endothelial growth factor-based therapy. A retrospective multicenter study (n = 34) explored HIF-1 alpha expression via immunohistochemistry in patients treated with platinum chemotherapy and bevacizumab. Median progression-free survival (PFS) was significantly lower in the HIF-1 alpha low score group compared to the high score group (4.9 vs 12.9 months, P = 0.014). Similarly, the median overall survival (OS) was significantly reduced in the HIF-1 alpha low score group (8.3 vs 20.4 months, P = 0.006). This study, the first of its kind, highlights the prognostic significance of HIF-1 alpha expression in metastatic cervical SCC patients treated with bevacizumab-based therapy

Internet of Things for Sustainable Human Health

The sustainable health IoT has the strong potential to bring tremendous improvements in human health and well-being through sensing, and monitoring of health impacts across the whole spectrum of climate change. The sustainable health IoT enables development of a systems approach in the area of human health and ecosystem. It allows integration of broader health sub-areas in a bigger archetype for improving sustainability in health in the realm of social, economic, and environmental sectors. This integration provides a powerful health IoT framework for sustainable health and community goals in the wake of changing climate. In this chapter, a detailed description of climate-related health impacts on human health is provided. The sensing, communications, and monitoring technologies are discussed. The impact of key environmental and human health factors on the development of new IoT technologies also analyzed

Hydrogen sorption in crystalline and amorphous Mg-Cu thin films

A study was carried out to examine the hydrogenation behavior of 300 nm, Pd-capped, Mg-Cu thin films with Cu contents of 5, 10 and 15 at.%. The films were produced via thermal evaporation of Mg and Cu co-deposited onto glass substrates at two different temperatures: 298 and 223 K. The samples produced at 298 K were all crystalline, the structure being refined with increase in the Cu content. The films deposited at 223 K developed structures that were either refined, i.e. Mg(95)Cu(5); or amorphous, i.e. Mg(90)Cu(10) and Mg(85)Cu(15). The hydrogen sorption of the films was followed by resistance measurements, with the samples heated isochronally, initially under hydrogen and then under vacuum. The resistance data have shown that an increase in Cu content, or a decrease in the substrate temperature, improves the sorption characteristics of the films by reducing both the absorption and desorption temperatures. The lowest desorption temperature achieved was 323 K. The study suggests that an amorphous alloy of Mg(90)Cu(10) could be used as hydrogen storage medium as it would store 5.9 wt.% hydrogen in near-ambient conditions and could desorp it at around 100 degrees C. 2009 Elsevier B.V. All rights reserved

Isochronal hydrogenation of textured Mg/Pd thin films

Magnesium thin films of 350 nm, capped with Pd, were deposited on glass substrates and hydrogenated in two different conditions; namely isochronal and isothermal. As-deposited films were highly textured with Mg (001) parallel to the glass substrate. Experiments have shown that under isothermal conditions starting from 333 K, Mg films can absorb hydrogen producing MgH(2) with a random texture. When the films were heated slowly starting from the room temperature, hydrogenation gives rise to a textured MgH2, where (110) parallel to the substrate. (101) is also present in this texture as a minor component. Formation of the textured hydride in isochronal loading was discussed within the context of the lattice mismatch in a Mg to MgH(2) transformation

Ti modified Pd-Ag membranes for hydrogen separation

An investigation was carried out into Pd-Ag separation membranes to check whether a reduction in their Pd content was possible through the incorporation of a third element, namely Ti. For this purpose a combinatorial thin film deposition system was developed incorporating three sputter targets arranged in triangular form. The system had a substrate in the form of a magazine, 6 inch in diameter, accommodating 21 discs arranged again in triangular form aligned with the targets underneath. With this geometry, a library of thin film membranes was obtained in a single experiment covering a wide compositional field, Pd content up to of approx. 75%. The thin film library was then screened with respect their tendency to react with hydrogen. This was accomplished by the resistivity measurements carried out on the membranes, while they are subjected to heating-cooling cycle under hydrogen, the values being compared with identical cycle carried out under argon. Since permeability is a product of hydrogen solubility and diffusivity, membranes that react with hydrogen, i.e. either forming a solid solution or a hydride, delineate compositions which are candidates for separation membranes. In the present work, this procedure was applied to a portion of Ag-Ti Pd ternary system aiming for separation membranes with f.c.c. crystal structure. Mapping based on the resistivity measurement indicated, Ag35Ti22Pd43, Ag13Ti25Pd62 and their near compositions as possible candidates for separation membranes. Copyright (c) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved