Spatially Controlled Occlusion of Polymer‐Stabilized Gold Nanoparticles within ZnO

In principle, incorporating nanoparticles into growing crystals offers an attractive and highly convenient route for the production of a wide range of novel nanocomposites. Herein we describe an efficient aqueous route that enables the spatially controlled occlusion of gold nanoparticles (AuNPs) within ZnO crystals at up to 20 % by mass. Depending on the precise synthesis protocol, these AuNPs can be (i) solely located within a central region, (ii) uniformly distributed throughout the ZnO host crystal or (iii) confined to a surface layer. Remarkably, such efficient occlusion is mediated by a non‐ionic water‐soluble polymer, poly(glycerol monomethacrylate)₇₀ (G₇₀), which is chemically grafted to the AuNPs; pendent cis‐diol side groups on this steric stabilizer bind Zn²⁺ cations, which promotes nanoparticle interaction with the growing ZnO crystals. Finally, uniform occlusion of G₇₀‐AuNPs within this inorganic host leads to faster UV‐induced photodegradation of a model dye.     

Structure and Physicochemical Mechanisms of Interaction of Bone Tissue with Titanium Implants in Cases of Tuberculous Osteitis

Technical Physics - The structural and physicochemical mechanisms of interaction of bone tissue with titanium implants under conditions of tuberculous osteitis are studied using scanning electron...     

Influence of the dehydration procedure on the physicochemical properties of nanocrystalline hydroxylapatite xerogel

The influence of various dehydration procedures on the physicochemical properties of hydroxylapatite gel was examined. The best dehydration procedure is freezing, leading to the formation of a nanocrystalline hydroxylapatite powder without intermediate formation of a monolithic xerogel. Examination by the layer self-arrangement method, scanning electron microscopy, and atomic-force microscopy showed that the powder particles are spherical aggregates from 0.4 to 2.0 μm in size, consisting of nanoparticles 16–30 nm in diameter.     

Antimicrobial activity and agricultural properties of bitter melon (Momordica charantia L.) grown in northern parts of Turkey: a case study for adaptation

This study was designed to determine the adaptation capability of bitter melon (Momordica charantia L.), which is widely grown in tropical and subtropical climates, in northern parts of Turkey. In this study, plant height, number of fruits, fruit length, fruit width, number of seeds and fruit weight of bitter melon grown in field conditions were determined. The antimicrobial effect of the ethanol extract of fruit and seeds against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Salmonella typhi, Aspergillus niger and Candida albicans microorganisms was tested in vitro by the disc diffusion method. In conclusion, plant height (260 cm), number of fruits (16 per plant), number of seeds (30.2 per fruit), fruit width (3.8 cm), fruit length (10.6 cm) and fruit weight (117.28 g fruit^? 1) were determined; fruits were found to have antimicrobial activity against A. niger; oil and seeds were found to have antimicrobial activity against A. niger and E. coli.     

Features of acousto-optic interaction in uniaxial gyrotropic crystals

The features of noncollinear acousto-optic interaction in gyrotropic crystals in the intermediate diffraction regime and the regime of Bragg diffraction were investigated. The dependence of the efficiency of diffraction in gyrotropic paratellurite, tellurium, and quartz crystals on the intensity of the ultrasonic wave, acousto-optic interaction length, and incident-light polarization was investigated. It is shown that the gyrotropy of the crystal is responsible for the appearance of a multiple-peak structure of the Bragg maximum. It has been established that in the case of propagation of incident and diffracted waves in the vicinity of the optical axis of the crystal, the diffraction efficiency is independent of the polarization state of the incident light. The results of theoretical calculations are in agreement with the experimental results obtained for uniaxial crystals. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 1, pp. 105–110, January–February, 2000.