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This paper reports high frequency surface acoustic wave (SAW) devices developed on Sc doped (30%) AlN on high resistivity Si for demonstrating surface acoustic wave – spin wave coupling. Enhanced Q-factors were found for both propagation modes – Rayleigh (4.7 GHz) and Sezawa (8 GHz). SAW/SW (spin wave) coupling is proven for two-ports SAW structures having a magnetostrictive layer of Ni between the two interdigitated transducers (IDTs). A decrease of 3.42 dB was observed in the amplitude of the transmission parameter, at resonance, when the magnetic field was applied. The angle between the applied magnetic field and the SAW propagation direction is π/4.

A compact analytical model is reported capturing the effects of Coulomb Blockade and charge quantization on the drain current characteristics of a MOSFET-based semiconductor quantum dot at cryogenic temperatures. It is implemented as a Verilog-A add-on to the foundry-provided MOSFET model to facilitate potential integration in any design kit and allow for simulation of quantum processors that integrate qubits and control electronics on the same die. The model was verified in the 6-50 K temperature range on the measured I-V characteristics of a nanoscale p-MOSFET fabricated in production 22nm FDSOI CMOS technology.

Thin AlN piezoelectric layers have been deposited on high resistivity Si and glass substrates by reactive RF magnetron sputtering, in order to manufacture one-port gigahertz operating surface acoustic wave (SAW)-type resonators to be used as temperature sensors. The growth morphology surface topography, crystallographic structure, and crystalline quality of the AlN layers have been analyzed. Advanced nanolithographic techniques have been used to manufacture structures having interdigitated transducers with fingers and finger interdigit spacing width in the range of 250–170 nm. High resonance frequency ensures the increase of the sensitivity, but also of its normalized value, the temperature coefficient of frequency (TCF). The resonance frequency shift versus temperature has been measured in the −267°C−+150°C temperature range, using a cryostat setup adapted for on wafer microwave measurements up to 50 GHz. The sensitivity and the TCF were determined in the 25 °C–150 °C temperature range.

This work analyzes resonance frequency shift vs. the applied magnetic field strength for GHz operating GaN/Si SAW single resonators. Magnetostrictive elements (Ni and CoFeB) were deposited in the proximity of the interdigitated transducers (IDTs) of the resonators (A-type structures) and also over the IDTs, after covering them with a BCB layer to avoid short circuits with IDTs metal (B-type structures). This work targets emerging applications of SAW resonators in driving spin wave pumping and in coupling of surface acoustic waves (SAW) with superconducting Q-bits. Magnetic sensitivity of the SAWs was analyzed at room temperature (RT) and at cryogenic temperatures, obtaining high magnetic sensitivities at 16 K. According to our knowledge, GaN based SAWs are first time used in magnetic applications; also, cryogenic behavior of magnetic SAW sensors is first time analyzed., This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No. 801055 "Spin Wave Computing for Ultimately-Scaled Hybrid Low-Power Electronics" - CHIRON

In the current work we present AIN/Si based Surface Acoustic Wave (SAW) devices exploited as high sensitivity temperature sensors. The experimental results show that the resonance frequency varies between 3.2 and 5.5 GHz, depending on the finger/interdigit spacing width and metal thickness. The temperature measurements were performed between −250°C and +150 °C in a cryostat. The sensitivities were investigated between 24–150 °C and the values were compared to the results obtained for similar GaN/Si based SAW structures.

Present work is focused on obtaining and characterization of sol–gel thin films belonging to SiO2–P2O5–Er2O3 (I) and SiO2–P2O5–Pr2O3 (II) systems. The films have been obtained by spin coating technique for three rotation speeds: 2000, 3500 and 5000 rpm. The deposition of the films was performed at different periods of time, i.e. 24 h, 96 h, 120 h, 144 h and 168 h after instant preparation of the precursor sols. FTIR (Fourier transform infrared spectroscopy) and Raman characterization aimed at investigating the structural changes that occurred in silicophosphate network in dependence on the spin rate of the substrate as well as on the time period elapsed since the sol preparation till the deposition day. FTIR spectra recorded in the 400–4000 cm−1 range revealed Si–O–Si, P–O–P and Si–O–P vibration modes and optical phonons specific for OH units. Raman spectra collected in the 100–4000 cm−1 range put in evidence stretching, bending and mixed vibration modes specific for silicophosphate network as well as rare-earth ion peaks specific to certain electronic transitions. Morphological investigation made by AFM (atomic force microscopy) on Er and Pr-doped silicophosphate sol–gel films evidenced specific features depending on the parameters mentioned above and SEM (scanning electron microscopy) analysis revealed micron sphere structural units, exfoliation of the films and micro cracks.

The article reports the preparation and complex characterization of iron-containing phosphate glasses considered to be ecological materials, as they contain non-toxic compounds related to environment. The oxide system Li2O–MgO–(CaO)–Al2O3–P2O5–(FeO/Fe2O3) was investigated in respect to its structural changes caused by MgO replacement with CaO and by the iron addition. UV–vis–NIR (ultraviolet–visible–near infrared) spectroscopy as well as thermo-gravimetric (TG) measurements, differential thermo-analysis (DTA), X-ray diffraction (XRD) analysis, electronic paramagnetic resonance (EPR), and Mossbauer (nuclear gamma resonance) spectroscopy have been used to investigate redox states and coordination symmetry of iron, together with vitreous network changes during the heat treatment up to 1000 °C. UV–vis–NIR transmission spectroscopy revealed no structural modifications when MgO was substituted by CaO, but noteworthy absorption bands attributed to Fe2+/Fe3+ species. TG analysis made in the 20–1000 °C range shows low weight loss accompanied by several thermal effects, as evidenced by DTA. XRD patterns for the glass samples heat treated at about 700 °C revealed the presence of different phosphate crystalline phases containing Mg, Al, and Fe ions. EPR spectroscopy revealed the presence of paramagnetic Fe3+ ions and the change of the first coordination symmetry, when the samples are heated below the vitreous transition temperature. Mossbauer spectroscopy has evidenced two paramagnetic species, Fe2+ and Fe3+, both in octahedral coordination symmetry and a clustering process supported by only Fe3+ ions.

The present work deals with ecological phosphate and silicate glasses that belong to the oxide systems: Li2O-MgO-P2O5, Li2O-CaO-P2O5, Li2O-MgO-P2O5-Fe2O3; Li2O-CaO-P2O5-Fe2O3 and SiO2-R2O-R′O (R = Na, K; R′ = Mg, Ca), the last system contains certain amounts of ZrO2, ZnO, TiO2. These ecological glasses do not contain toxic substances as BaO, PbO, As2O3, As2O5, fluorine, CdS, CdSe and they have applications as regards the retention and counteracting action of the harmful compounds resulted from the nuclear plants. The replacement of MgO by CaO leads to an insignificant increasing of the thermal expansion index and a slight decreasing of the characteristic temperatures, except the softening point where the effect is opposite. Adding of iron oxide in the phosphate glass composition causes the increasing of characteristic temperatures and the decreasing of thermal expansion index, both in MgO and CaO-containing phosphate glasses. The ecological silicate glasses are used as opal glasses free of fluorine as well as for lead-free crystal glass (CFP) where BaO and PbO are replaced by non-toxic oxides as K2O, MgO, ZrO2, and TiO2. The paper presents different glass compositions and the technological parameters to prepare the ecological glass samples. Both ecological phosphate and silicate glasses have been characterized as regards the characteristic temperatures (vitreous transition point, low and high annealing points, softening point) and the thermal expansion coefficient. This study presents the changes of the thermal parameters when CaO replaces MgO in phosphate glass samples and the role of iron oxide in the vitreous network. In the case of silicate glasses, the viscosity and wetting angle dependency of temperature are presented. The elemental analysis of the ecological glasses was made by XPS (X-ray photoelectron spectroscopy) which also put in evidence the iron species from the vitreous network.

Many structural materials have been placed in the live body in attempt to aid the body in repairing processes of diseases. The predominantly used materials in the treatment of various diseases have been and still are metals and polymers. The materials that can function intimately with the living cells tissue, with minimal adverse reaction, must be manufactured as multiple metallic or nonmetallic phases. Titanium and its alloys are considered to be the most attractive metallic materials for biomedical applications because of their excellent mechanical properties, corrosion resistance and biocompatibility [1]. In recent years, many methods have been applied to improve the biocompatibility and biofunctionality of titanium-based implants. Conducting polymers such as polypyrrole (PPy) offer a new class of material for trial use in biological applications. PPy has been chosen as coating polymer to protect the metal implant against corrosion and could be surface modified with biologically active molecules able to stimulate positive interactions with bone tissue [2, 3]. Surface modification of these materials with biological moieties is desired to enhance the biomaterial-tissue interface and to promote desired tissue responses. Heparin (HE) is a potent anticoagulant that can be immobilized on biomaterial surfaces to increase their hemocompatibility. Many ingenious and useful techniques have been evolved for modifying the surface structure, while keeping the bulk structure unchanged. The plasma polymerization is the process mostly used for the deposition of thin polymer and polymer-based composite films with a variable amount of functionalities available for reaction with biomolecules [1, 4, 5]. In this context, the strategy followed was based on a plasma deposition of PPy and PPyHE films onto Ti substrate. Heparin was immobilized on/in the PPy films using plasma processing. Heparin was chosen because it is a component of the extracellular matrix of blood vessels and has anticoagulant properties. The chemical composition and the morphology of the polymeric films PPy and Ppy-HE films deposited onto Ti substrate were investigated using Fourier transform infrared (FTIR), Raman spectroscopy and atomic force microscopy (AFM). Results showed that HE was incorporated into the PPy matrix and is presented on particle surface.

The proper choice of a measurement technique is only one step in the development of a successful application. All steps leading up to the measurement are equally important to the sampling and the sample preparation process begins at the point of collection and extends to the measurement step. The sample preparation method used to convert the sample into a form suitable for the measurement step can have a greater effect on the overall accuracy and reability of the results and the measurement itself. Sample preparation is one of the important problems in analytical process. The microwave digestion coupled with ICP MS measurements, for the heavy metals analysis is a very useful tools for the environmental samples.

Summary:Confidenceinthepotentialofhydrogenasanenergyvectorandfuelbringthe opportunities for enhancing electrolyzer performance. The aim of this paper is todevelop new polymer nanocomposites as electrolyte membranes for PEM-electro-lyzer. A series of nanocomposite membranes, including GEFC/TiO 2 , GEFC/CNTs, andGEFC/TiO 2 CNTs have been developed and characterized by FT-IR spectroscopy andAFM. The application ofpolymer nanocomposite membranes in electrochemical cellsforwaterelectrolysiswasinvestigated.Experimental resultsobtainedwithrespecttoperformance are reported and discussed related to GEFC membrane. Keywords: ion exchangers; membranes; nanocomposites; nanostructures; PEM-electrolyzer Introduction Electrolyzer technology may be implemen-ted at a variety of scales wherever there isan electricity supply to provide hydrogenand/or oxygen for nearly any requirement.The increasing demand for hydrogen pro-duce by latest advances in fuel celltechnology are driving the need for thedevelopment of materials involved inH

The investigated ecological glasses with no toxic compounds, such as BaO, PbO, As2O3, As2O5, fluorine, CdS and CdSe in their composition are located in ternary and quaternary oxide systems: ZnO-SiO2-TiO2 and SiO2-R'2O-R''O-R'''O2, where R' is Na or K, R'' is Ca or Mg and R''' is Zr or Ti. The first system contains P2O5, ZnO and TiO2 in order to obtain opal glasses, without fluorine compounds. The second system replaces the barium oxide and lead oxide with potassium, magnesium, zirconium and titanium oxides, for materials like lead free crystals. The raw materials can be replaced by silicate or borosilicate glass waste. The advantages of borosilicate glass waste are: bringing valuable components into recipes (B2O3, CaO, Al2O3), saving raw materials and energy, creating an ecological environment The characteristic temperatures (vitreous transition point, low and high annealing points, softening point) and the thermal expansion coefficient of the glass are presented. The FTIR and Raman spectroscopy provided structural data, such as characteristic vibration maxima for silicon and titanium oxide, and revealed the role of zinc oxide in the vitreous network. The refraction index and UV-VIS transmission are discussed.

We have demonstrated successful thin film growth of poly(1,3-bis-( p -carboxyphenoxy, propane)- co -(sebacic anhydride)) (20:80) by matrix-assisted pulsed laser evaporation using a KrF* excimer laser ( λ = 248 nm, τ = 25 ns, ν = 10 Hz). The deposited thin films have been investigated by Fourier transform infrared spectroscopy, and atomic force microscopy. We have demonstrated that the main functional groups of poly(1,3-bis-( p -carboxyphenoxy, propane)- co -(sebacic anhydride)) (20:80) are present in the deposited film. The effect of matrix on both thin film structure and surface morphology was also examined. The goal of this work is to explore laser processing of this material to create suitable constructs for drug delivery applications.

Bionanocomposites Staphylococcus aureus/carbon nanotubes were prepared and their biocompatibility with different species of carbon nanotubes (CNTs) evaluated in terms of their incorporation into a microbial fuel cell (MFC) anodic design. Multi wall carbon nanotubes (MWNTs) with various morphologies and structures, as received, and synthesized by the pyrolysis of novolac with ferrocene addition were used. MWNTs were characterized by TEM and FT-IR spectroscopy. Optical microscopy with fluorescent quantum dots (QDs) have been used for bio-labeling, microorganisms-CNTs biocompatibility and rapid identification of the colonies developed. Designed BNCs are good culture cells media and the electrodes based on synthesized CNTs could be used with good effects in MFCs, from the point of view of bacteria biocompatibility.

In the present work, we explore the possibility to deposit polyanilineesilicon dioxide (PAnieSiO2) and polythiopheneesilicon dioxide (PTheSiO2) nanocomposites through a plasma polymerization route. The films were generated by spraying of mixtures of nano-sized silica particles dispersed in the liquid monomer into a plasma stream of the DC-plasma discharge reactor. The silica in the resulted polymer matrix changes the conduction mechanisms varying from ohmic to ballistic and traps inducing the space charged limited currents (SCLC). The silica modifies the morphology and composition of the deposited films. 2005 Published by Elsevier Ltd.

A co-spraying method of binary mixture aniline–single-walled nanotubes (SWNTs) in a plasma stream is proposed as an alternative to design new composites and nanotube functionalizing. The electrical characterizations, Fourier transform-infrared spectroscopy (FT-IR) and Raman spectra show a chemical bonding to the nanotube surface. I–V characteristics show a combined effect of the conduction mechanisms imposed by space charged limited currents (SLCS) and the metallic/semimetallic character of the nanotubes.

Electromagnetic interferences (EMI)-shielding, anticorrosion, antistatic, trace detector for radiation particles remain open subjects for nanocomposites to find appropriate solutions. In many practical aspects needs an appropriate combination between EMI-properties with high mechanical strength and thermal stability. In this respect, we report a new method to design nanocomposites films based on spin-coating in thermo-centrifugal field. The films are made of polyacrylonitrile (PAN) matrix with polyaniline (PAni) nanoparticles aligned in micron wires with a given periodicity dependent on spinning parameters. The films have a texture similar with diffraction grating, anisotropy in electrical conduction over percolation threshold determined by chain orientation. Structural, morphological and optical characterizations show a high degree of orientation of the macromolecular chains which follow the same anisotropy as in electrical conductivity. Loss tangent in the frequency range from 1 kHz to 0.2 GHz shows a strong attenuation.

The plasma polymerization for long time encountered many difficulties to reproduce the chemical routes having the advantage to deposit thin and continuous films. Due to high energy of the plasma, pinholes, cross-linking and polymers with low molecular weight have been an impediment to plasma polymerization. The method proposed by the direct injection of the monomer in the plasma bulk under mild condition reduced many of these inconveniences. In particular, it has been proven on pyrrole and pyrrole with ferrocene that continuous and homogeneous polymer films can be deposited similar as with the chemical method for synthesis. The polymeric films were characterized by FT-IR, Raman and AFM. The results show that ferrocene units are embedded between pyrrole units giving a very interesting organic–inorganic copolymer.

We report a cheap and reliable method to produce thin films nanocomposites with a novel method of plasma polymerization having coupled an atomizer head. In particular, Polyaniline-nanocarbons (PPAniNC) were deposited on silicon substrate aiming at nanocomposites with functional gradient properties, proton exchange membranes with catalytic effect, electronic transport with charge accumulation and electromagnetic shielding. Combining the aniline with dispersed nanocarbons (NC) and polymerized in plasma is one of the alternatives do match these requirements. The insertion of the nanometric carbons into polyaniline films has been accomplished by the simultaneous injection in the plasma reactor. The films were characterized by FT-IR, Raman, AFM, and electrical measurements. The measurements show specific features, which demonstrate that the composites consisting of nano-sized carbon particles functionalized by chemical bonded between the polymer chains.

The plasma polymerization is the process commonly used for the deposition of the polymers in thin films with specific properties for applications ranged from low k-dielectrics to membranes, light emitting electrochemical cells, anticorrosion and metallic polymers. Usually, the plasma polymers have extremely low electrical conductivity (>10−12 S/cm) and only by chemical doping, the conductivity can be increased with few orders but the results are not concluded for applications. The usual methods in the plasma polymerization are not appropriate for doping such as the electrochemical and chemical one. To avoid these inconveniences a special design is proposed to induce doping simultaneous with plasma deposition of the polymers. This method has many similarities with electrospray ionization. This study reports the results in plasma polymerization of aniline (PPAni) close to emeraldine base and doped with p-toluene sulphonic acid (PPAniPTS) during the deposition. As-polymerized PPAni shows an electrical conductivity ∼2 × 10−9 S/cm. The doping with p-toluene sulphonic acid (in very small amount) shows considerable changes in I–V characteristics and the electrical conductivity increases to ∼10−7 S/cm. The conduction mechanism is space charge limited conduction (SCLC) and is governed by shallow and deep traps originated from sulphonic groups. The films have been characterized by FT-IR, Raman and AFM.

Catalyst assisted chemical vapor deposition(CVD)is one of the most viable routes in production of carbon nanotubes(CNTs), but purification and deposition in oriented position still remain an open question. This contribution presents a method to deposit high-quality nanotubes, using RF-plasma assisted CVD and catalytic decomposition of a ferrocene-toluene mixture in a quartz tube reactor. The most important phenomena that have been encountered are that the iron released from ferrocene play catalyst role only on a characteristic length, being removed after that by plasma etching. Raman spectroscopy and Transmission Electron Microscopy(TEM)characterized the obtained carbon structures.

The authors investigated the prevalence of tardive dyskinesia among elderly psychiatric patients who had never received neuroleptic medication before their first hospitalization.The study was performed in the geriatric psychiatry unit of a university-affiliated hospital in Canada and involved all first-admission patients admitted from September 1984 through August 1989 who had never taken neuroleptic drugs. In September and October 1989, the patients who were available for follow-up were examined and given ratings on the Abnormal Involuntary Movement Scale to establish the presence or absence of tardive dyskinesia. The patients' records were reviewed for information on age, diagnosis, duration of hospitalization, neuroleptic treatment received after admission, anticholinergic drugs received, and drug-free periods.Of the 162 patients who were available and whose data were analyzed, a total of 99 had been treated with neuroleptics, and 35 (35.4%) of these were found to have tardive dyskinesia. Two of the 35 also had tardive dystonia. Significantly more patients with major depression than patients with primary degenerative dementia or delusional psychosis had tardive dyskinesia.This study confirms the higher vulnerability of elderly psychiatric patients treated with neuroleptics to the development of tardive dyskinesia. The authors stress that caution is especially necessary when neuroleptics are prescribed for older patients with major affective disorders.

Carbon supported Pd and PtPd catalysts were prepared by chemical reduction of metal precursors with sodium borohydride. Multi-wall carbon nanotubes (MWNTs) were used as carbon support. The composition of prepared catalysts was given by EDX technique. Cyclic voltammetry (CV) measurements were used to evaluate the electrocatalytic activities for methanol electrooxidation after their immobilization onto carbon paper.

Composite solid acid/nanooxide polymer membranes with good electrical behaviour can be obtained by thermocentrifugal field processing. The supporting polymer matrix is designed to embed solid acids or strong solid acids/nanooxides making it appropriate for proton conducting composite membranes. Nanocomposites CsHSO4-YSZ/PAN membranes were investigated by Raman, FT-IR and SEM techniques. The dependence of the electrical conductivity on temperature is evaluated.

Although carbamazepine is known to cause hyponatremia, no previous reports have indicated an interaction between carbamazepine and a diuretic. Two patients are described who were treated with this combination and developed symptomatic hyponatremia, which cleared when both drugs were discontinued in one patient and when the diuretic was discontinued in the second patient. The possible mechanisms of action of carbamazepine-induced hyponatremia are discussed.

A group of 116 lithium-treated patients (53 men, 63 women) with predominant diagnoses of affective disorders were systematically examined for the presence of thyroid disorders. Nine (7.8%) patients (2 men, 7 women) were found to suffer from hypothyroidism after a mean of 3.4 years of lithium therapy. An increase in thyroid-stimulating hormone without clinical hypothyroidism was noted in 2 (1.7%) patients (both men). Hyperthyroidism with a full-blown picture of thyrotoxic nodular goiter was noted in 1 woman, and temporary increases in thyroxine and triiodothyronine were noted in another woman. These findings are discussed in light of other studies.

Fractional hepatic extraction of glucose was determined from the appearance in the systemic circulation of ingested 3-[3H]glucose. Using the glucose clamp technique, studies were done under steady-state conditions of basal glycemia and insulinemia, normoglycemia (0.8 mg/mL) and mild hyperinsulinemia (approximately 40 microU/mL), hyperglycemia (2 mg/mL-1) and hyperinsulinemia (approximately 100 microU/mL). Based on previous results in the dog, an oral glucose load of 2 g was used to label the portal vein glucose; this amount was chosen so as to minimize disturbance of the portal steady state but still avoid excessive loss during absorption. Additional subjects with hyperglycemia and hyperinsulinemia received an oral load of 50 g of glucose. Fractional extraction in normal subjects under near-basal conditions of glycemia and insulinemia was 19% in normal subjects and in patients with noninsulin-dependent diabetes mellitus (NIDDM) elevation of serum insulin, with or without hyperglycemia, which led to an average extraction rate of 32% of the ingested glucose. Absolute hepatic glucose uptake, calculated from the fractional extraction the plasma glucose concentration, and hepatic plasma flow accounted for 50% to 72% of total glucose use during the various steady states and following ingestion of 50 g of glucose. It is concluded that hepatic uptake or extraction, as opposed to net uptake, proceeds actively even when plasma glucose and insulin are within the normal basal range; it is increased in the presence of hyperinsulinemia, with or without hyperglycemia; and it is unaltered in NIDDM.