Bistable Boron-Related Defect Associated with the Acceptor Removal Process in Irradiated -Type Silicon-Electronic Properties of Configurational Transformations.

The acceptor removal process is the most detrimental effect encountered in irradiated boron-doped silicon. This process is caused by a radiation-induced boron-containing donor (BCD) defect with bistable properties that are reflected in the electrical measurements performed in usual ambient laboratory conditions. In this work, the electronic properties of the BCD defect in its two different configurations (A and B) and the kinetics behind transformations are determined from the variations in the capacitance-voltage characteristics in the 243-308 K temperature range.

Deciphering the role of water and a zinc-doping process in a polyol-based approach for obtaining Zn/Co/Al-based spinels: toward "green" mesoporous inorganic pigments.

Two new families of zinc/cobalt/aluminum-based pigments, with a unique composition, were obtained through the polyol method. The hydrolysis process of a mixture of Co(CHCOO), Zn(acac) and Al(acac) (acac = acetylacetonate ion) in 1,4-butanediol afforded dark blue gels (wPZnxCo1-xAl), in the presence of a supplementary amount of water, and light green powders (PZnxCo1-xAl), respectively, for the water-free procedure ( = 0, 0.2, 0.

Optoelectronic and stability properties of quasi-2D alkylammonium based perovskites.

Electronic and stability properties of quasi-2D alkylammonium perovskites are investigated using density functional theory (DFT) calculations and validated experimentally on selected classes of compounds. Our analysis is focused on perovskite structures of formula (A)(A')PbX, with large cations A = butyl-, pentyl-, hexylammonium (BA, PA, HXA), small cations A' = methylammonium, formamidinium, ethylammonium, guanidinium (MA, FA, EA, GA) and halogens X = I, Br, Cl. The role of the halogen ions is outlined for the band structure, stability and defect formation energies.

The Impact of Cardiac Chamber Volumes on Permanent His Bundle Pacing Procedural Outcomes-A Single Center Experience.

His bundle pacing (HBP) has several pitfalls, such as the inability to identify the His bundle and lack of capture at acceptable thresholds. The majority of data regarding HBP were obtained using a dedicated non-deflectable delivery system. This study aimed to evaluate the impact of cardiac chamber dimensions on permanent HBP procedural outcomes when using this type of fixed-curve catheter.

Controlling polarization direction in epitaxial Pb(ZrTi)O films through Nb (n-type) and Fe (p-type) doping.

Fe (acceptor) and Nb (donor) doped epitaxial Pb(ZrTi)O (PZT) films were grown on single crystal SrTiO substrates and their electric properties were compared to those of un-doped PZT layers deposited in similar conditions. All the films were grown from targets produced from high purity precursor oxides and the doping was in the limit of 1% atomic in both cases. The remnant polarization, the coercive field and the potential barriers at electrode interfaces are different, with lowest values for Fe doping and highest values for Nb doping, with un-doped PZT in between.

Homogeneous versus Inhomogeneous Polarization Switching in PZT Thin Films: Impact of the Structural Quality and Correlation to the Negative Capacitance Effect.

Polarization switching in ferroelectric films is exploited in many applications, such as non-volatile memories and negative capacitance field affect transistors. This can be inhomogeneous or homogeneous, depending on if ferroelectric domains are forming or not during the switching process. The relation between the polarization switching, the structural quality of the films and the negative capacitance was not studied in depth.

Tetragonal-Cubic Phase Transition and Low-Field Dielectric Properties of CHNHPbI Crystals.

The frequency and temperature dependence of dielectric properties of CHNHPbI (MAPI) crystals have been studied and analyzed in connection with temperature-dependent structural studies. The obtained results bring arguments for the existence of ferroelectricity and aim to complete the current knowledge on the thermally activated conduction mechanisms, in dark equilibrium and in the presence of a small external a.c.

Accidental Impurities in Epitaxial Pb(ZrTi)O Thin Films Grown by Pulsed Laser Deposition and Their Impact on the Macroscopic Electric Properties.

Structural and electrical properties of epitaxial Pb(ZrTi)O films grown by pulsed laser deposition from targets with different purities are investigated in this study. One target was produced in-house by using high purity precursor oxides (at least 99.99%), and the other target was a commercial product (99.

Structural Details of BaTiO Nano-Powders Deduced from the Anisotropic XRD Peak Broadening.

In this study, nano-BaTiO (BTO) powders were obtained via the solvothermal method at different reaction times and were investigated using transmission electron microscopy (TEM), X-ray diffraction (XRD) and Raman spectroscopy. The results were compared with those obtained for a larger crystallite size BTO powder (BTO-m). The sizes of the cuboid crystallites (as determined by XRD and TEM) ranged from about 18 to 24 nm, depending on the reaction time.

Influence of Sintering Strategy on the Characteristics of Sol-Gel BaCeTiO Ceramics.

Single-phase Ce-doped BaTiO powders described by the nominal formula BaCeTiO with = 0.005 and 0.05 were synthesized by the acetate variant of the sol-gel method.

Low value for the static background dielectric constant in epitaxial PZT thin films.

Ferroelectrics are intensively studied materials due to their unique properties with high potential for applications. Despite all efforts devoted to obtain the values of ferroelectric material constants, the problem of the magnitude of static dielectric constant remains unsolved. In this article it is shown that the value of the static dielectric constant at zero electric field and with negligible contribution from the ferroelectric polarization (also called static background dielectric constant, or just background dielectric constant) can be very low (between 10 and 15), possibly converging towards the value in the optical domain.

Carbon-based sprayed electrodes for pyroelectric applications.

A carbon-based layer was deposited by spraying on top of a ferroelectric layer grown by sol-gel on Si (001) substrate and its properties as electrode and absorber for pyroelectric detection were tested. It was found that the electric properties of the ferroelectric capacitor with top carbon-based sprayed electrode (CBSE) are comparable with those of the capacitors with standard top SrRuO3 (SRO)/Au electrode. Pyroelectric measurements show that the pyroelectric signal recorded on ferroelectric capacitors with top CBSE electrode is 2.

Atrial electrical remodeling induced by chronic ischemia and inflammation in patients with stable coronary artery disease.

The pathophysiology of coronary artery disease (CAD) includes low-grade chronic inflammation. At its turn, inflammation is known to promote myocardial structural remodeling and to increase vulnerability to atrial arrhythmias. Meanwhile, the impact of chronic inflammation on the electrophysiological properties of the atria remains unknown.

Multiple polarization states in symmetric ferroelectric heterostructures for multi-bit non-volatile memories.

Here we report a ferroelectric capacitor structure obtained by alternating ferroelectric and insulator thin-film layers which allows an increase of up to 2 polarization states, with n the number of ferroelectric layers. Four and up to eight distinct, stable and independently addressed polarization states are experimentally demonstrated in this work. The experimental findings are supported by a theoretical model based on the Landau-Ginzburg-Devonshire theory.

Iodine Migration and Degradation of Perovskite Solar Cells Enhanced by Metallic Electrodes.

We monitored the evolution in time of pinhole-free structures based on FTO/TiO/CHNHPbICl layers, with and without spiro-OMeTAD and counter electrodes (Ag, Mo/Ag, and Au), aged at 24 °C in a dark nitrogen atmosphere. In the absence of electrodes, no degradation occurs. While devices with Au show only a 10% drop in power conversion efficiency, remaining stable after a further overheating at 70 °C, >90% is lost when using Ag, with the process being slower for Mo/Ag.

Polarization induced self-doping in epitaxial Pb(Zr0.20Ti0.80)O3 thin films.

The compensation of the depolarization field in ferroelectric layers requires the presence of a suitable amount of charges able to follow any variation of the ferroelectric polarization. These can be free carriers or charged defects located in the ferroelectric material or free carriers coming from the electrodes. Here we show that a self-doping phenomenon occurs in epitaxial, tetragonal ferroelectric films of Pb(Zr0.

Frustration of ferroelectricity in epitaxial film of relaxor ferroelectric PbSc1/2Nb1/2O3.

Relaxor-to-ferroelectric transformations induced by varying electric fields and temperatures are studied experimentally in acube-on-cubetype epitaxial PbSc(1/2)Nb(1/2)O3 film grown on La(1/2)Sr(1/2)CoO3/MgO(001). Dielectric response, quasi-static and dynamic polarization, and dynamic current-voltage characteristics evidence the absence of spontaneous relaxor-to-ferroelectric transition. The electricfield-induced transformation from a glass-like relaxor state to a new dynamic polar state is detected at low temperatures below 100 K only.

Nutrition in inflammatory bowel diseases.

The relationship between nutrition and inflammatory bowel disease (IBD) is a complex one, the evaluation and correction of nutritional deficits being integral part of therapy in these patients. The diet that consists in excessive consumption of meat, sugar, fats (with a higher 0 6 /o) 3 polyunsaturated fatty acids ratio) are factors involved in the epidemiology and pathogenesis of IBD. Malnutrition is present among most IBD patients, being the result of multiple mechanisms from digestive symptoms to inflammatory process, intestinal resection and administration of medications.

Polarization-control of the potential barrier at the electrode interfaces in epitaxial ferroelectric thin films.

Electrode interface is a key element in controlling the macroscopic electrical properties of the ferroelectric capacitors based on thin films. In the case of epitaxial ferroelectrics, the electrode interface is essential in controlling the leakage current and the polarization switching, two important elements in the read/write processes of nonvolatile memories. However, the relation between the polarization bound charges and the electronic properties of the electrode interfaces is not yet well understood.

The prevalence of anaemia in patients with inflammatory bowel diseases in North-Eastern Romania.

Unlabelled: Anemia is a frequent complication of inflammatory bowel diseases (IBD). The main incriminated mechanisms are the iron deficiency and the chronic inflammation. The aim of this study was to determine the prevalence of anemia in IBD patients and to identify the main causes.

Quality of life in patients with ulcerative colitis.

Unlabelled: Patients with inflammatory bowel disease (IBD) have to live with the perspective of a potential disability, which may lead in time to impaired quality of life (QoL). In order to fully understand the impact of IBD on patients and their careers we need to quantify the QoL.

Aim: To evaluate HRQol in ulcerative colitis patients as opposed to the general population and to identify the significant changes of HRQoL in accordance with the specific progression of UC.

Study of radiation damage induced by 12 keV X-rays in MOS structures built on high-resistivity n-type silicon.

Imaging experiments at the European X-ray Free Electron Laser (XFEL) require silicon pixel sensors with extraordinary performance specifications: doses of up to 1 GGy of 12 keV photons, up to 10(5) 12 keV photons per 200 µm × 200 µm pixel arriving within less than 100 fs, and a time interval between XFEL pulses of 220 ns. To address these challenges, in particular the question of radiation damage, the properties of the SiO(2) layer and of the Si-SiO(2) interface, using MOS (metal-oxide-semiconductor) capacitors manufactured on high-resistivity n-type silicon irradiated to X-ray doses between 10 kGy and 1 GGy, have been studied. Measurements of capacitance/conductance-voltage (C/G-V) at different frequencies, as well as of thermal dielectric relaxation current (TDRC), have been performed.

[Diagnostic difficulties in mammary gland adenosis. Case report].

Tumor adenosis represents a rare lesion, which most frequent appears as a palpable mass, with more than the usual dimensions. The paper presents a case of tumor adenosis of the mammary gland of a 16 years girl. Macroscopically, the tumor was well delimited, with gray-white surface and a nodular aspect on section.