Search results for "Rods"
showing 10 items of 76 documents
Application of graphene quantum dots in heavy metals and pesticides detection
2020
Graphene Quantum Dots (GQDs) were produced using electrochemical oxidation of graphite rods. Obtained GQDs were gamma-irradiated in the presence of the N atoms source, ethylenediamine. Both structural and morphological changes were investigated using UV-Vis, X-ray photoelectron and photoluminescence (PL) spectroscopy as well as atomic force microscopy. The ability of both types of dots to change PL intensity in the presence of pesticides such as malathion and glyphosate, as well as copper (II) ions was detected. These preliminary results indicated a high potential of produced GQDs to be applied as non-enzymatic PL sensors for the detection of selected pesticides and metal ions. 26th Interna…
Blue-violet heterojunction LEDs based on hydrothermally synthesized ZnO nanorods
2016
Zinc oxide nanorods have great potential for the realization of high efficiency heterostructure LEDs based on p-doped GaN. Well-aligned vertical nanorods are desirable to enhance the LED outcoupling performances due to a better confinement of the light [1]. However, due to the lack of reproducible p-type ZnO, a p-GaN substrate is still needed. This work reports on the fabrication of n-ZnO/p-GaN heterojunction LEDs based on vertical ZnO nanorods grown by hydrothermal method. The chemical reaction in the hydrothermal growth of ZnO is based on the decomposition of zinc nitrate, (Zn(NO3)2) with resulting Zn2+ ions reacting with the hydroxyl ions obtained by the thermal degradation of hexamethyl…
O2-sensing and O2-dependent gene regulation in facultatively anaerobic bacteria.
1995
Availability of O2 is one of the most important regulatory signals in facultatively anaerobic bacteria. Various two- or one-component sensor/regulator systems control the expression of aerobic and anaerobic metabolism in response to O2. Most of the sensor proteins contain heme or Fe as cofactors that interact with O2 either by binding or by a redox reaction. The ArcA/ArcB regulator of aerobic metabolism in Escherichia coli may use a different sensory mechanism. In two-component regulators, the sensor is located in the cytoplasmic membrane, whereas one-component regulators are located in the cytoplasm. Under most conditions, O2 can readily reach the cytoplasm and could provide the signal in …
Arodveselības riski strādājošajiem kokapstrādē un veselības veicināšanas pasākumi
2019
“ Arodveselības riski strādājošajiem kokapstrādē un veselības veicināšanas pasākumi”. Darba autore : Zane Vīle-Bērziņa. Darba zinātniskā vadītāja: Dr. med.,asociētā profesore Ženija Roja. Darbs izklāstīts uz 83 lpp., ietver: 38 attēlus, 5 tabulas, 11 pielikumus, 30 informatīvos avotus. Maģistra darba struktūra veidota no četrām daļām. Pirmajā daļā apkopota un analizēta literatūra par darba vides riskiem kokapstrādē un to ietekmi uz arodslimību attīstību Latvijā, kā arī to galvenos rašanās cēloņus salīdzināt ar SIA “JELD-WEN LATVIJA” arodslimību rašanās cēloņiem. Literatūras analīze uzrāda , ka galvenie arodsalimšanu rašānās celoņi ir pārlieku lielā fiziska slodze un ergonomiskie riski, kas …
Case of fatal systemic infection with an Aureobacterium sp.: identification of isolate by 16S rRNA gene analysis
1996
The case of a 75-year-old man who succumbed to a disseminated infection most likely caused by a species of the genus Aureobacterium is reported. Identification of the isolate was achieved by comparative 16S rRNA gene analysis. Aureobacteria are commonly found in the environment. However, only recently have they been recognized as a cause of infections including septicemia and soft tissue infections. To our knowledge, this is the first documentation of a fatal infection caused by an Aureobacterium sp.
Photoelectrochemical removal of chlorfenvinphos by using WO3 nanorods: Influence of annealing temperature and operation pH
2019
[EN] A visible-light driven photoelectrochemical degradation process has been applied to a solution polluted with the organophosphate insecticide chlorfenvinphos. Different WO3 nanosheets/nanorods have been used as photoanodes. These nanostructured electrodes have been fabricated by anodization of tungsten and, subsequently, they have been subjected to a thermal treatment (annealing). The combined influence of annealing temperature (400¿°C and 600¿°C) and operation pH (1 and 3) on the photoelectrocatalytic behavior of these nanorods has been examined through a statistical analysis. Morphological, structural and photoelectrochemical characterizations have also been carried out. The chlorfenv…
Progress in Violet Light-Emitting Diodes Based on ZnO/GaN Heterojunction
2020
Progress in light-emitting diodes (LEDs) based on ZnO/GaN heterojunctions has run into several obstacles during the last twenty years. While both the energy bandgap and lattice parameter of the two semiconductors are favorable to the development of such devices, other features related to the electrical and structural properties of the GaN layer prevent an efficient radiative recombination. This work illustrates some advances made on ZnO/GaN-based LEDs, by using high-thickness GaN layers for the p-region of the device and an ad hoc device topology. Heterojunction LEDs consist of a quasicoalesced non-intentionally doped ZnO nanorod layer deposited by chemical bath deposition onto a metal&ndash
Well-aligned hydrothermally synthesized zinc oxide nanorods on p-GaN without a seed layer
2015
Zinc oxide nanorods have great potential for the realization of high efficiency heterostructure LEDs based on pdoped gallium nitride. In order to obtain a good confinement of the light, a well-aligned nanorod waveguiding structure is desirable. This paper reports on the fabrication of vertical zinc oxide nanorods using a solution-based growth process that does not require a seed layer. The nanorods obtained follow the crystalline growth direction of the GaN layer along the c-axis. Various results with different reagent concentrations are reported.
Printing ZnO Inks: From Principles to Devices
2020
Solution-based printing approaches permit digital designs to be converted into physical objects by depositing materials in a layer-by-layer additive fashion from microscale to nanoscale resolution. The extraordinary adaptability of this technology to different inks and substrates has received substantial interest in the recent literature. In such a context, this review specifically focuses on the realization of inks for the deposition of ZnO, a well-known wide bandgap semiconductor inorganic material showing an impressive number of applications in electronic, optoelectronic, and piezoelectric devices. Herein, we present an updated review of the latest advancements on the ink formulations an…
Mechanical properties of MDCK II cells exposed to gold nanorods
2015
Background: The impact of gold nanoparticles on cell viability has been extensively studied in the past. Size, shape and surface functionalization including opsonization of gold particles ranging from a few nanometers to hundreds of nanometers are among the most crucial parameters that have been focussed on. Cytoxicity of nanomaterial has been assessed by common cytotoxicity assays targeting enzymatic activity such as LDH, MTT and ECIS. So far, however, less attention has been paid to the mechanical parameters of cells exposed to gold particles, which is an important reporter on the cellular response to external stimuli.Results: Mechanical properties of confluent MDCK II cells exposed to go…