Optimization of Electrospray Deposition Conditions of ZnO Thin Films for Ammonia Sensing.

This study focuses on the influence of electrospray deposition parameters on the morphology, topography, optical and sensing properties of ZnO films deposited on gold electrodes of quartz crystal resonators. The substrate temperature, precursor feed rate and emitter's voltage were varied. Zinc acetate dehydrate dissolved in a mixture of deionized water, ethanol and acetic acid was used as a precursor.

Blending Approach Preparation of PVA--PMA Films with Embedded "Green" Synthesized Silver Nanoparticles for Acetone Optical Detection.

The blending approach (also known as the ex-situ approach) was used for the deposition of thin composite films comprising poly(vinyl alcohol--methyl acrylate) (PVA--PMA) and silver nanoparticles (AgNPs). Firstly, the copolymer aqueous dispersion was synthesized through the redox polymerization of methyl acrylate (MA) on poly(vinyl alcohol) (PVA) using ammonium cerium (IV) nitrate as the initiator. Then, AgNPs were synthesized through a "green" method using the water extract of lavender based on by-products of the essential oil industry, and then they were blended with the polymer.

A case of a child with four parasites in Bulgaria.

Children are more susceptible to intestinal parasitic diseases than adults due to their lack of hygiene habits and close social interactions with their peers. We present a case of a 5-year-old boy with diarrhea and abdominal pain. The stool sample and perianal swab were examined in LINA laboratory, Burgas, Bulgaria.

Acetone-Sensitive Thin Films Comprising Coal Fly Ash Na-X Zeolites and Sol-Gel NbO Matrix.

In this study, thin composite films of a sol-gel NbO matrix doped with coal fly ash Na-X zeolites were deposited by the spin-coating method. Fly ash of lignite coal collected from the electrostatic precipitators of one of the biggest TPPs in Bulgaria was used as a raw material for obtaining zeolites. Zeolite Na-X was synthesized by ultrasonic-assisted double stage fusion-hydrothermal alkaline conversion of coal fly ash.

Flexible and Transparent Polymer-Based Optical Humidity Sensor.

Thin spin-coated polymer films of amphiphilic copolymer obtained by partial acetalization of poly (vinyl alcohol) are used as humidity-sensitive media. They are deposited on polymer substrate (PET) in order to obtain a flexible humidity sensor. Pre-metallization of substrate is implemented for increasing the optical contrast of the sensor, thus improving the sensitivity.

Progress in the Utilization of Coal Fly Ash by Conversion to Zeolites with Green Energy Applications.

Fly ash (FA) from lignite coal combusted in different Thermal Power Plants (TPPs) was used for the synthesis of zeolites (FAZs) of the Na-X type by alkaline activation via three laboratory procedures. FAZs were characterized with respect to their morphology, phase composition and surface properties, which predetermine their suitability for applications as catalysts and adsorbents. FAZs were subsequently modified with metal oxides (CuO) to improve their catalytic properties.

Optical Sensing of Humidity Using Polymer Top-Covered Bragg Stacks and Polymer/Metal Thin Film Structures.

Thin films with nanometer thicknesses in the range 100-400 nm are prepared from double hydrophilic copolymers of complex branched structures containing poly(-dimethyl acrylamide) and poly(ethylene oxide) blocks and are used as humidity sensitive media. Instead of using glass or opaque wafer for substrates, polymer thin films are deposited on Bragg stacks and thin (30 nm) sputtered Au-Pd films thus bringing color for the colorless polymer/glass system and enabling transmittance measurements for humidity sensing. All samples are characterized by transmittance measurements at different humidity levels in the range from 5% to 90% relative humidity.

Influence of Macromolecular Architecture on the Optical and Humidity-Sensing Properties of Poly(,-Dimethylacrylamide)-Based Block Copolymers.

The influence of the macromolecular architecture of block copolymers containing poly(,-dimethyl acrylamide) (PDMA) on the optical characteristics and sensing properties of corresponding thin films is discussed. Series of hydrophilic PDMA-based copolymers of different chemical composition and chain architecture such as triblock, star-shaped, and branched were synthesized. The copolymers were characterized using conventional spectroscopic techniques as well as methods for characterization of copolymer macromolecular characteristics in solution, namely size-exclusion chromatography and static light scattering.

HyCCAPP as a tool to characterize promoter DNA-protein interactions in Saccharomyces cerevisiae.

Currently available methods for interrogating DNA-protein interactions at individual genomic loci have significant limitations, and make it difficult to work with unmodified cells or examine single-copy regions without specific antibodies. In this study, we describe a physiological application of the Hybridization Capture of Chromatin-Associated Proteins for Proteomics (HyCCAPP) methodology we have developed. Both novel and known locus-specific DNA-protein interactions were identified at the ENO2 and GAL1 promoter regions of Saccharomyces cerevisiae, and revealed subgroups of proteins present in significantly different levels at the loci in cells grown on glucose versus galactose as the carbon source.

Vapor responsive one-dimensional photonic crystals from zeolite nanoparticles and metal oxide films for optical sensing.

The preparation of responsive multilayered structures with quarter-wave design based on layer-by-layer deposition of sol-gel derived Nb(2)O(5) films and spin-coated MEL type zeolite is demonstrated. The refractive indices (n) and thicknesses (d) of the layers are determined using non-linear curve fitting of the measured reflectance spectra. Besides, the surface and cross-sectional features of the multilayered structures are characterized by scanning electron microscopy (SEM).

Zeolite films as building blocks for antireflective coatings and vapor responsive Bragg stacks.

Zeolite films (LTL, BEA and MFI) are prepared with a thickness in the range 50-170 nm through a multistep spin-on deposition method. The optical properties of the zeolite films including refractive index, extinction coefficient and thickness are determined from the reflectance spectra using a nonlinear curve fitting method. The total free pore volume of the films using the Bruggeman effective medium theory is calculated.

[Acute poisoning by tricyclic antidepressants in childhood].

The authors share their experience in the clinical observation and treatment of 72 children with acute intoxications by tricyclic antidepressants. The syndromes, forming the clinical picture of the acute intoxication at that age were the cerebrotoxic, cholinolytic and cardiotoxic ones. According to their content, the intoxication advanced in three forms: light, moderately severe and severe.

[Liver enzyme function and humoral immunity in workers exposed to vinyl chloride].

The work aims at studying the enzyme function of the liver, as well as the humoral immunity of workers engaged in the production of vinyl chloride and polyvinylchloride with proved hepatotropic and Raynaud syndromes. About 191 workers /experimental group/ from the synthesis and polymerization of vinyl chloride and 2 control groups--34 persons from Varna and 54 from G. Traĭkov were examined.