Electroluminescence from single nanowires by tunnel injection: an experimental study

We present a hybrid light-emitting diode structure composed of an n-type gallium nitride nanowire on a p-type silicon substrate in which current is injected along the length of the nanowire. The device emits ultraviolet light under both bias polarities. Tunnel-injection of holes from the p-type substrate (under forward bias) and from the metal (under reverse bias) through thin native oxide barriers consistently explains the observed electroluminescence behaviour. This work shows that the standard p-n junction model is generally not applicable to this kind of device structure.Comment: 6 pages, 6 figure

Applications of Nanostructural NiTi Alloys for Medical Devices

New nanostructural shape memory alloy (55.91 wt% of Ni and 44.03 wt% of Ti) for the production of minimally invasive implantation medical devices (stents) was tested for corrosion resistance under static conditions by dipping it into solutions with various acidities (pH from 1.68 to 9.18) for 2 years, for static mechanical properties and for biocompatibility. The material for investigations was 280‐μm wires before and after thermal treatment at 450°C for 15 min in air and surface mechanical treatment. The characteristic image and size of grains were determined using the transmission electron microscope (TEM), and the phase composition; surface morphology; and the layer‐by‐layer composition were investigated using an X‐ray diffractometer; a scanning electron microscope (SEM); and an Auger spectrometer. The nickel release from the investigated nanostructural nitinol is less in comparison with data for microstructural nitinol in a solution of any acidity. Dissolution in the alkali medium is absent. A significant retardation of the nickel ion release (and insignificant concentration as a whole) and the absence of titanium ion release in the weakly acidic and neutral solutions with polished samples are observed. A simultaneous 7–11% increase in strength and plasticity in comparison with microstructural nitinol was attained. Toxicity of samples has not been revealed

Gallium hydride vapor phase epitaxy of GaN nanowires

Straight GaN nanowires (NWs) with diameters of 50 nm, lengths up to 10 μm and a hexagonal wurtzite crystal structure have been grown at 900°C on 0.5 nm Au/Si(001) via the reaction of Ga with NH3 and N2:H2, where the H2 content was varied between 10 and 100%. The growth of high-quality GaN NWs depends critically on the thickness of Au and Ga vapor pressure while no deposition occurs on plain Si(001). Increasing the H2 content leads to an increase in the growth rate, a reduction in the areal density of the GaN NWs and a suppression of the underlying amorphous (α)-like GaN layer which occurs without H2. The increase in growth rate with H2 content is a direct consequence of the reaction of Ga with H2 which leads to the formation of Ga hydride that reacts efficiently with NH3 at the top of the GaN NWs. Moreover, the reduction in the areal density of the GaN NWs and suppression of the α-like GaN layer is attributed to the reaction of H2 with Ga in the immediate vicinity of the Au NPs. Finally, the incorporation of H2 leads to a significant improvement in the near band edge photoluminescence through a suppression of the non-radiative recombination via surface states which become passivated not only via H2, but also via a reduction of O2-related defects

Epitaxial Catalyst-Free Growth of InN Nanorods onc-Plane Sapphire

We report observation of catalyst-free hydride vapor phase epitaxy growth of InN nanorods. Characterization of the nanorods with transmission electron microscopy, and X-ray diffraction show that the nanorods are stoichiometric 2H–InN single crystals growing in the [0001] orientation. The InN rods are uniform, showing very little variation in both diameter and length. Surprisingly, the rods show clear epitaxial relations with thec-plane sapphire substrate, despite about 29% of lattice mismatch. Comparing catalyst-free with Ni-catalyzed growth, the only difference observed is in the density of nucleation sites, suggesting that Ni does not work like the typical vapor–liquid–solid catalyst, but rather functions as a nucleation promoter by catalyzing the decomposition of ammonia. No conclusive photoluminescence was observed from single nanorods, while integrating over a large area showed weak wide emissions centered at 0.78 and at 1.9 eV

Morphological composition of carcasses and muscle development of eland antelope

Studied veterinary-sanitary indicators of portioned and small-sized myelinated semi-finished beef meat, pork, lamb and white meat bird in comparison with the feed in the initial period of experience in storage and production refrigerated for 5 days. Noted a marked change in the organoleptic, physics-chemical and microbiological indicators of semi-finished products as compared with the original raw meat. Deviations in indicators of laboratorian studies revealed most often in semi-finished products made of pork and poultry meat. Based on the data developed proposals to reduce the shelf life of meat products depending on the source of veterinary-sanitary indicators of meat products

Rationale of veterinary and sanitary evaluation of pig slaughter product at cryptosporidiosis period

The article presents the results of research carried out in order to support veterinary and sanitary assessment of products of slaughter pigs with invasive disease - cryptosporidiosis. This disease affects many species of animals and birds, it is considered dangerous to humans. The clinical manifestation of the disease observed in young animals, adult animals is characterized by a long asymptomatic carriage of the pathogen. At slaughtering enterprises, unfortunately, do not diagnose the cryptosporidiosis. This leads to the use of meat and other animal products of slaughter without any restriction, which is safe for consumers. Presented in the article the results of researches allow improving the diagnosis of cryptosporidiosis in slaughter pigs and recommending methods for the safest use of meat in the food and feed purposes. Proposals on veterinary and sanitary assessment of meat to obtained results of organoleptic, physical-chemical and microbiological tests as well as the danger of cryptosporidiosis pathogen for humans

IMPROVEMENT OF VETERINARY AND SANITARY EXAMINATION OF SALMON CAVIAR

Materials on veterinary and sanitary examination of salmon caviar, sold in the network of trade enterprises and in the markets of Moscow, are provided. We studied the assortment of red caviar in trade enterprises, the demand for red caviar by different layers of the population, analyzed the veterinary and sanitary requirements for salmon caviar, analyzed the samples of commercial salmon caviar in the pre-sent-day mode, determined the types of commercial falsification in order to determine the quality and safety of salmon caviar. On the basis of the data obtained, proposals have been developed to improve the veterinary and sanitary examination of salmon caviar which help to identify various falsifications of red caviar, sold in trade enterprises and food markets

Veterinary-sanitary characteristics of meat when used in diet supplements Activ Ist and sea buckthorn shrot

We studied the possibility of using additives Activ Ist and Sea buckthorn shrot for growing broiler meat. Proven increase of daily weight gain of chickens, improvement in physical characteristics and composition of meat, safety and bioavailability of meat products, recommend veterinary-sanitary assessment for slaughter broilers when using these supplements

Veterinary-sanitary characteristics of argan oil ( Argania spinosa L.)

Studied vegetable oil produced in Morocco from the seeds of the rare fruit tree, argan tree prickly, methods of obtaining argan oil, its chemical composition and the use of population in the pharmaceutical and cosmetic industries. Conducted sensory and microbiological evaluation of food and technical (non-food) argan oil delivered from Morocco