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The present research aimed to electrodeposit and characterize Ni-W alloys for different technological parameters, being an example of “induced co-deposition”, in which a certain metal (for example: Mo, W) can be co-deposited as an alloy, but it cannot be measured in its pure state. The investigated characteristics were the efficiency current, the average thickness, and the structural properties of the obtained deposits. The current efficiency decreases with an increased applied current density, and the tungsten content remains constant at around 11% for different current densities (10 mA·cm−2 and 16 mA·cm−2, respectively). An increase in the temperature of the electrolyte leads to the inclusion of more tungsten. The deposit tungsten content and the current efficiency are directly related to pH. The deposit hardness directly relates to the alloy composition, deposit morphology, and coating thickness. The higher hardness, approximatively 100 HV were measured and the optimal brightness were observed for the alloys obtained at increased current density (i = 16 mA·cm−2, T = 50°C, pH = 8), or to a basic pH (i = 10 mA·cm−2, T = 50°C, pH = 9.23). The scanning electron microscopy (SEM) technique was used to analyze the surface morphology, and energy dispersive spectroscopy (EDS) analysis was carried out to determine the composition of the alloys. The metallic surface brightness (%) was evaluated using the miniature spectrometer, based on the reflection property of the electrodeposited metallic layer, scanning the all-wavelength range between 200-1100 nm.

The recent use of digital Distributed Ledger Technology (DLT) in the healthcare domain can surpass the existing limitations in the centralized IT systems, such as the lack of security, access control or immutability of the electronic health information. If we discuss about clinical information, this innovative informatics advance gives back the control to the data owner. In decentralized environments, smart contracts allow trustable agreements grounded by irreversible transactions, which permit transparency and traceability. Moreover, smart contracts are the living heart of the decentralized applications that run on DTL. In this work, our attention is focused on medical equipments that helps health staff to diagnose and treat patients keeping much of their clinical data taken in dynamics. Hence, we propose a smart contract-based decentralized application framework for the management of devices, targeting also medical services, meant to facilitate the interaction of the involved entities. Our testing environment is the Ethereum platform, extensively used recently in the healthcare domain, being itself a smart operating system that allows decentralized applications to run on it.

Intelligent assistive technologies represent a concept that refers to products and services that can offset functional limitations, facilitate independent life, improve their quality of life, and enable people with disabilities to reach their own potential. This paper presents a medical recovery exergaming that includes a Microsoft Kinect Motion Sensor, designed for upper limb rehabilitation, especially for old people with brain disorders. The game is 3D and during the game, the user has to pick up the red or green apples according to a level, and different angles of inclination of the neck, hand, shoulder, and so on are measured and then a total score is generated. To know if the patient has progressed in his medical recovery, the final score should be increased. In order to find the score that a subject without a locomotor system disorder can achieve, we have optimized the game with mathematical modeling and canonical analysis by applying response surface methodology and multiple nonlinear regression. The exergaming based on VR active games represents a useful tool in physical and cognitive rehabilitation for people with motor impairments or brain disorders, considering the advantage of home-training. info:eu-repo/semantics/publishedVersion

Without data we cannot understand the pandemic. Only based on good data can we know how the disease is spreading, what impact the pandemic has on the lives of people around the world, and whether the countermeasures countries are taking are successful or not. But even the best available data on the coronavirus pandemic is far from perfect. In this chapter we present the latest data together with detailed explanations of what we can learn from this data: where does the data come from and what are the limitations that we need to be aware of. And what does the data tell us about the coronavirus pandemic in a particular country, Romania.

As the interest toward communication-based vehicle safety applications is increasing, the development of secure wireless communication techniques has become an important research area. In this context, the article addresses issues that are related to the use of the visible light communication (VLC) technology in vehicular applications. Thus, it provides an extensive presentation concerning the main challenges and issues that are associated to vehicular VLC applications and of some of the existing VLC solutions. Moreover, the article presents the aspects related to the design and intensive experimental evaluation of a new automotive VLC system. The experimental evaluation performed in indoor and outdoor conditions shows that the proposed system can achieve communication distances up to 50 m and bit error ratio (BER) lower than 10&minus, 6, while being exposed to optical and weather perturbations. This article provides important evidence concerning the snowfall effect on middle to long range outdoor VLC, as the proposed VLC system was also evaluated in snowfall conditions. Accordingly, the experimental evaluation showed that snowfall and heavy gust could increase bit error rate by up to 10,000 times. Even so, this article provides encouraging evidence that VLC systems will soon be able to reliably support V2X communications.

Application and implementation of Internet of Things principles promise to radically change our regular lifestyle. Beyond the tempting facilities offered by smart home appliances, this work proposes some innovative medical applications of Internet of Things Relevant aspects related to the structure of a system based on brainwave interfaces, the results obtained so far, as well as the high complexity of these systems were analyzed. Besides, in the current and especially the future technological context, a new challenge - independent green energy, was introduced. Capturing and recovering the energy from ambient EMF will be the“ zero-power” solution of sensor networks, already recognized as one of the most important technologies for real-world deployment of Internet of Things systems.

In this paper the novel high-temperature resistant polymers with nonlinear optical properties have been synthesized, characterized and tested for use in electro-optical components with high bit rate optical signal processing systems and for dynamic holography. The characterization that has been reported include the measurement of second-order nonlinear susceptibility by second harmonic generation, UV-VIS spectroscopy, XRD measurement dielectric relaxation, glass transition temperature and molecular weight distribution before and after artificial ageing. Also, we have done AFM investigations and profilometry measurements for stamp patterning layers. The application of the new polyimides for electro-optic devices has been evaluated by creation of thin oriented polymer films on various substrates and preparation of planar and strip waveguides.

An alloy surface with possible applications in the medical field, Ti4A14Zr, was improved through the deposition of a thin hydroxyapatite (HA) layer. In this paper, we analyzed the growth of a HA layer through electrophoresis and the corrosion resistance of the metallic sample covered with the ceramic layer. The substrate surface was processed via chemical procedures before the HA deposition. The state of the metallic surface and that of the layer of HA were investigated using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analysis of the chemical composition. The results indicate a high increase in the corrosion resistance associated with the ceramic layer compared to the metallic basic layer. Moreover, the analysis revealed the formation of a homogeneous TiO2 layer on the surface of the metallic substrate. The titanium oxide layer identified by SEM–EDS and confirmed by EIS was very homogeneous and resistant, with a compact microstructural appearance and submicron dimension. The layer composed of TiO2 and HA provided good corrosion protection.

Finite element analysis studies have been of interest in the field of orthodontics and this is due to the ability to study the stress in the bone, periodontal ligament (PDL), teeth and the displacement in the bone by using this method. Our study aimed to present a method that determines the effect of applying orthodontic forces in bodily direction on a healthy and reduced periodontium and to demonstrate the utility of finite element analysis. Using the cone-beam computed tomography (CBCT) of a patient with a healthy and reduced periodontium, we modeled the geometric construction of the contour of the elements necessary for the study. Afterwards, we applied a force of 1 N and a force of 0.8 N in order to achieve bodily movement and to analyze the stress in the bone, in the periodontal ligament and the absolute displacement. The analysis of the applied forces showed that a minimal ligament thickness is correlated with the highest value of the maximum stress in the PDL and a decreased displacement. This confirms the results obtained in previous clinical practice, confirming the validity of the simulation. During orthodontic tooth movement, the morphology of the teeth and of the periodontium should be taken into account. The effect of orthodontic forces on a particular anatomy could be studied using FEA, a method that provides real data. This is necessary for proper treatment planning and its particularization depends on the patient’s particular situation.

Spinel-type semiconductor compounds represent an alternative for robust and inexpensive detection systems, due to their good thermal and chemical stability in operation. The sensing mechanism is based on the change in electric resistivity when exposed to specific gaseous ambient, resulting from chemical reactions between metal-oxide surface and gas molecules. Sample composition and morphology are key factors in determining the selectivity and sensitivity of solid-state sensors. In this work structural, morphological and sensory characteristics of some porous oxide semiconductors with spinel-type structure (Nk 0.99 Co 0.01 Mn 0.02 Fe 1.98 O 4-δ , Li 0.5 Sm 0.1 Fe 2.4 O 4 and Mg 0.9 Sn 0.1 Fe 2 O 4 ) are presented. The self-combustion technique was used to prepare these compounds. This method offers the advantage of obtaining nanosized reproducible and porous ceramics with high specific surface area and exact stoichiometry. Investigated compounds hold promise for high-performance applications in acetone sensors.

Thin films of new pyrrolo [ 1 , 2 - a ] [ 1 , 10 ] phenanthroline derivatives have been investigated by ultraviolet photoelectron spectroscopy, with a view of future applications in optoelectronic devices. The electronic band structure of investigated compounds (for electron energies ⩽ 25 eV ) is to a great extent determined by substituent (R = NO 2 , Cl) induced transformations of molecular orbitals.

The investigation of conversion of new soluble poly( p -phenylenevinylene) (PPV) precursor and PPV patterns by irradiation with UV light of a film is reported. We obtained patterns by this method with well-defined edges and channel width up to 10 μm. Also, it was found that the PPV precursor polymer is a photoresist material. This allows the fabrication of PPV patterns, which can directly act as luminescent structures in organic light-emitting diodes (OLEDs). Using the atomic force microscopy (AFM) technique, investigations on the PPV thin films show that at 200 °C well-defined crystalline domains of PPV are detected, thus indicating the complete transformation of the precursor into the final polymer. The current–voltage characteristics of single and double PPV layer devices indicate that turn-on voltages around 9 and 8 V were recorded for double and single PPV layer devices, respectively. From the electroluminescence–voltage plot, an onset voltage at 10 V is detected for two PPV layers OLED. In addition, we investigate the optical, electrical and EL characteristics of pyrrolo[1,2-a][1,10]phenanthroline derivatives [Leontie L, Druta I, Danac R, Rusu GI. Synth Met 2005;155/1:138; Zugravescu I, Petrovanu M. 3+2 Dipolar cycloaddition. Bucharest: Roman Academic Publishing House; 1987 [in Romanian]; Druta I, Andrei M, Aburel P. Tetrahedron 1998;54:2107; Druta I, Dinica R, Bacu E, Humelnicu I. Tetrahedron 1998;54:10811; Dinica R, Druta I, Pettinari C. Synlett 2000;7:1013; Danac R, Rotaru A, Drochioiu G, Druta I. J Heterocyclic Chem 2003;40:283; Druta I, Danac R, Barbieru R, Tapu D, Andrei M. Sci Ann Al I Cuza Univ Iasi S Chem 2001;IX:149] as potential candidates for OLED applications. In this case, PPV was used as the hole-transport layer (HTL) and pyrrolo[1,2-a][1,10]phenanthroline derivatives, which were spin coated onto PPV, as the emissive layer. The structure of all PPV devices reported in this paper was fabricated using UV light for patterning.

An analysis of a vacuum-deposited fluorene-thiophene-based material 5,5′-Di(9,9′-di-(butyl)-fluorene-2,2′-bithiophene) (DBFBT) onto different substrates, which can act as dielectric gate for organic field-effect transistor is made. Also a new method for preparation of high-quality dielectric thin films made of polytetrafluoroethylene (PTFE) is described. This method includes film formation by means of a special kind of vacuum deposition polymerization (VDP) of PTFE, assisted by electron cloud activation. Rubbing of these layers makes them orienting substrate materials which induce spontaneous ordering of deposited organic semiconductor layers. We investigated structure and morphology of PTFE layers deposited by vacuum process in dependence on deposition parameters: deposition rate, deposition temperature, electron activation energy and activation current. The molecular structure of the PTFE films was investigated by use of infrared spectroscopy. By means of ellipsometry, values of refractive index between 1.33 and 1.36 have been obtained for PTFE films in dependence on deposition conditions. Using the cold friction technique orienting PTFE layers with unidirectional grooves are obtained. We have shown that DBFBT layers growth on top of rubbed PTFE films present a certain alignment suitable for building organic field-effect transistors with better transport parameters.

The temperature dependence of d.c. electrical conductivity, σ , and Seebeck's coefficient, S , for seven new synthesized 1-( p -R-benzoyl)-1,2,3,3 a -tetrahydropyrrolo-[1,2- a ][1,10]-phenanthrolin-2,3-( N -R′)-dicarboximide compounds, has been investigated. Thin film samples ( d = 0.09–0.94 μm) deposited from dimethylformamide solutions, by an immersion technique, onto glass were used. X-ray diffraction (XRD) analyses were performed for the investigation of crystalline structure of as-prepared films, while atomic force microscopy (AFM) technique, corroborated to optical microscopy was used for the examination of surface morphology. The behavior of σ and S as a function of temperature is typical for polycrystalline semiconducting (n-type) materials. The activation energy of electrical conduction laid in the range 1.21–1.82 eV, while the ratio of charge carrier mobilities ranged between 1.05 and 1.15. Some correlations between semiconducting properties and molecular structure of the compounds were established. The model based on band gap representation can be satisfactory used for the explanation of electronic transport in investigated compounds.

Temperature-dependent d.c. electric conductivity of some recently synthesized organic compounds, stable disubstituted 4-(4-pyridyl)pyridinium ylides, is studied. Thin-film samples ( d = 0.100.80 μm) spin-coated from dimethylformamide solutions onto glass substrates have been used. Organic films with reproducible electron transport properties can be obtained if, after deposition, they are submitted to a heat treatment within temperature range of 297 − 527 K. The studied polycrystalline compounds exhibit typical n -type semiconductor behavior. The activation energy of the electric conduction ranges between 0.59 and 0.94 eV. Some correlations between semiconducting parameters and molecular structure of the organic compounds have been discussed. In the higher temperature range ( T > 400 K), the electron transport in examined compounds can be interpreted in terms of the band gap representation model, while in the lower temperature range, the Mott's variable-range hopping conduction model was found to be appropriate. Some of the investigated compounds hold promise for thermistor applications.

We discuss in this progress report whether the surface investigations, means by ellipsometry, atomic force microscopy, spectroscopy and profilometry of Teflon (polytetrafluoroethlylene - PTFE) thin films deposed by electron sputtering in vacuum on different materials. The substrates materials can be used in bioengineering and medicine applications. We found that the surface morphology and structures properties of Teflon thin films depend of parameters selected in deposition process as deposition rate, substrates temperature, deposition temperature, electron activation energy. This study can be used to improve new medical applications and new optoelectronic devices. Recent reports in transfer cold friction of Teflon thin film layers are discussed in the context of material requirements for such special applications because the formation of or oriented networks gives new benefits of the surface obtained.

Mobile and at-home healthcare systems are becoming increasingly important due to the current hospital crowding and long access-time to health services. The use of modern information and communication technologies in health applications and the development of low-cost medical equipment appropriate to personal and home use are among the top research priorities worldwide. In this paper, we present the design and implementation of a novel wireless electrocardiography device which is user-friendly, low cost and low power consumer, and has a high degree of interconnectivity with terminals such as smartphone, laptops, tablets and PCs. These features make it appropriate for mobile and at-home healthcare applications.

Thermally stimulated processes have been studied in thin films of phenanthroline derives to describe the states that had been localized. Ultraviolet Photoelectron Spectroscopy had checked out before thin films of new pyrrolo[l,2-a][l,10] phenanthroline derivatives [1], in order to further applications in optoelectronic devices. The investigated compounds have an electronic band structure which is due to the substituent (R=NO2, Cl) induced transformations of molecular orbitals. Thermally stimulated discharge currents (TSDC) attested dipolar and charge transport mechanisms. Each TSDC peak has been assigned to elementary processes that are different utilizing in addition dielectric spectroscopy (DES), and the mean trap depths have been approximated from thermally stimulated luminescence (TSL) curves.