Search results

1

Synthesis of Silver Halide Nanosols

100%

Michalak E., Nowak P., Król-Gracz A., Dyonizy A.

Acta Physica Polonica A

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2012

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vol. 121

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issue 1

200-202

EN

The aim of this work was to establish the average size of silver halide nanosols. The method applied was based on the optical turbidance measurements in real time of crystallization process. Dilute turbid suspensions of silver bromide, chloride and iodide stabilized by excess of halide ions and gelatin were measured over wavelength range from 450 nm to 600 nm. Experimental results were compared with the scattering theory of Rayleigh. Relation between dosing rate of reactants to dispersion system and size of obtained silver halide crystals was investigated. Interest in crystalline gelatine-stabilised aqueous suspensions of silver halide is due to their application as a substrate for the synthesis of silver nanoparticles.

2

Fabrication and Characterization of AgNPs Incorporated PVA/ODA-MMT and PVP/ODA-MMT Nanofiber Structures by Green Electrospinning Nanotechnology as Excellent Conducting and Bioengineering Nanomaterial

100%

Bunyatova U., Rzayev Z., Koçum İ., Şimşek M., Yürüksoy M.

Acta Physica Polonica A

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2016

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vol. 129

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issue 4

431-435

EN

This work presents synthesis and characterization of novel nanofiber structures from the pure water solution blends of poly(vinyl alcohol, hydrolyzed 89%) (PVA/octadecylamine-montmorillonite (ODA-MMT, 5 mass%) as a matrix and poly(N-vinylpyrrolidone) (PVP)/ODA-MMT (5 mass%) as a partner preintercalated nanocomposites and their AgNPs incorporated derivatives by green electrospinning nanotechnology. The chemical and physical structures, surface morphologies, and conductivities were investigated by the Fourier transform infrared, X-ray diffraction, scanning electron microscopy, conducting analysis methods. The fabricated multifunctional nanofibers predominantly exhibit colloidal-like amorphous structures, which is an important factor to improve tendency to self-assembly and therefore, the conductivities of the nanofiber polyelectrolyte structures. Obtained morphologies of composite nanofibers show cross-section structures with fine diameter distribution with higher contact areas. The nanofiber composites show excellent electrical conductivity at temperature range of 20-45°C. The obtained unique properties of multifunctional nanofiber surfaces with higher contact areas can be used for wide applications in microelectronics, sensor devices, nanolithography (X-ray, E-beam and photoresists), electrochemical (surface functionalized electrods) and bioengineering processing.

3

Carbon Nanomaterials from Carbon Monoxide Using Nickel and Cobalt Catalysts

100%

Liszka B., Krztoń A., Pawlyta M.

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issue 3

471-474

EN

Two catalysts, nickel and cobalt, supported on MgO were used for carbon nanomaterials deposition by CO disproportionation. The syntheses were performed at 795 and 900 K in the hydrogen atmosphere. The resulting products were investigated using atomic force microscopy, scanning electron microscopy, and high-resolution transmission electron microscopy. Although in the literature carbon nanofibres are expected to form in the hydrogen presence, we obtained carbon nanotubes, which were multiwall and twisted with the outer diameter of 10-120 nm and the tube length up to 10 μm.

4

Preparation and Characterization of Two-Dimensional Ordered Arrays of Metallic Nanoparticles

100%

Kandulski W., Kosiorek A., Rybczyński J., Bauman D., Giersig M.

Acta Physica Polonica A

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2003

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vol. 104

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issue 5

495-502

EN

A method of obtaining large-scale 2D arrays of ordered metallic nanoparticles is presented. The arrays were prepared using nanosphere lithography based on the self-assembly of latex particles on a water surface. Using 496 nm and 1040 nm diameter particles, it was possible to prepare arrays of over one cm^2, with defect-free areas of over 50μ m^2. By the evaporation of nickel or gold, periodic metallic particle arrays were produced. Modification of the particle array morphology was also shown by using double-layered masks. Computer simulated mask models were used to reveal interesting morphologies obtainable by the application of multilayered masks.

5

Synthesis, Structure, Photoluminescence, and Raman Spectrum of Indium Oxide Nanowires

63%

Kim H., Na H., Yang J., Lee, C., Kim H.

Acta Physica Polonica A

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2011

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vol. 119

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issue 2

143-145

EN

Production of indium oxide (In_2O_3) whiskers at a very low temperature of 650°C was reported. The synthetic route was comprised of a thermal heating process of a mixture of In and Mg powders. We have investigated the structural properties of the as-synthesized nanowires by using X-ray diffraction and scanning electron microscopy. The product consisted of one-dimensional nanowires, with a crystalline cubic structure of In_2O_3. The photoluminescence measurement with the Gaussian fitting exhibited visible light emission bands centered at 2.1 eV and 2.8 eV. The peaks of the Raman spectrum were indexed to the modes being associated with cubic In_2O_3.

6

SiO_x Nanowires Produced on Molybdenum-Coated Si Substrates

63%

Kim H., Lee J., Yang J.

Acta Physica Polonica A

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2008

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vol. 113

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issue 3

1017-1020

EN

We synthesized SiO_x nanowires with diameters of 30-140 nm, for the first time by the simple heating of the Mo-coated Si substrates. X-ray diffraction, selected area electron diffraction, and energy-dispersive X-ray spectroscopy indicated that the nanowires were in an amorphous state, comprising Si and O only. Fitting the photoluminescence spectrum with Gaussian functions revealed that the nanowires exhibited significant photoluminescence intensities near blue and green light regions. We extensively discussed the possible growth mechanism of SiO_x nanowires.

7

Catalyst-Free Growth of Magnesium Oxide Whiskers and Their Characteristics

63%

Kim H., Kong M., Yang J.

Acta Physica Polonica A

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2008

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vol. 113

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issue 3

1021-1024

EN

This study reports the production of magnesium oxide (MgO) whiskers on silicon (Si) substrates by the thermal heating of MgB_2 powders. We investigated the structural properties of the as-synthesized whiskers by using X-ray diffraction, transmission electron microscopy, selected area electron diffraction, and scanning electron microscopy. The product consisted of one-dimensional whiskers with a square cross-section. The whiskers had a single-crystalline cubic structure of MgO. The photoluminescence measurement with the Gaussian fitting exhibited visible light emission bands centered at 2.39 eV and 2.91 eV. We proposed the growth of MgO whiskers to follow the vapor-solid mechanism.

8

Modifications in Near-Surface Layer of Transparent Dielectrics Ionized by Ultrashort Laser Pulses

63%

Komolov V., Przhibel'skii S.

Acta Physica Polonica A

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2008

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vol. 113

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issue 3

1029-1034

EN

Formation of spatially non-uniform mechanical tension in a transparent solid due to the lattice ionization under the intensive ultrashort laser pulses action is predicted and theoretically described. Within the framework of the continual theory of elasticity the estimation of both average values of deformation tensor and its variations in solid dielectric with non-uniform random distribution of ions was carried out. It was shown that three possible types of medium modification can arise in solid depending on its ionization degree and the thickness of ionized layer. Since the Coulomb fields inside ionized layer can be non-uniform, all three types of structuring can arise in solid simultaneously.

9

Characteristic Properties of Dy-Eu-Ce Co-Doped ZrO₂ Nanofibers Fabricated via Electrospinning

63%

Çıçek Bezır N., Evcın A., Kayali R., Kaşikçi Özen M., Esen K., Cambaz E.

Acta Physica Polonica A

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2016

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vol. 130

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issue 1

300-303

EN

Zirconium oxide (ZrO₂) is one of the widely studied oxide materials because of its excellent electrical, mechanical and optical properties. In this study, undoped and Dy-Eu-Ce co-doped ZrO₂ nanofibers were fabricated by electrospinning method and their crystal structure, surface morphology, optical properties, electrical and electronic properties, and chemical properties have been analyzed using X-ray diffraction, scanning electron microscope (SEM), UV/VIS spectrometer, four point probe technique (FPPT) energy dispersive X-ray (EDX) measurements, respectively.

10

Preparation, Study and Nanoscale Growth of Indium Oxide Thin Films

63%

Bagheri Khatibani A., Rozati S., Bargbidi Z.

Acta Physica Polonica A

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2012

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vol. 122

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issue 1

220-223

EN

Indium oxide (In_2O_3) thin films were deposited on glass substrate by varying substrate temperature in the range of 400-600C using the spray pyrolysis technique. In this research, physical properties of indium oxide thin films were studied and then nanocrystalline sizes at different substrate temperature were deeply compared and investigated. All films were characterized at room temperature using X-ray diffraction, scanning electron microscopy, atomic force microscopy, photoluminescence, the Hall effect and UV-visible spectrophotometer. The optimal substrate temperature to obtain films of high crystallographic quality was 575°C, for this temperature, the electrical resistivity was in the order of ρ=0.147 Ω cm. For comparing optical transmittance and electrical conductivity the best figure of merit of the films was achieved at 575C.

11

Comparison of Antibacterial Properties of Nano TiO_2 and ZnO Particle Filled Polymers

63%

Altan M., Yildirim H.

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vol. 125

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issue 2

645-647

EN

Antibacterial property for the plastic products is very important due to their wide spread usage in many areas close to human health such as a child toy or a food package. There are some methods to make polymers antibacterial such as ionizing radiation but they can be still infected by micro organisms during usage of them. The best and easy way to obtain antibacterial polymers is melt mixing of polymers with antibacterial agents. In this study, nano TiO_2 and ZnO particles were mixed with polypropylene and high density polyethylene with a twin screw extruder. Silane was applied to the particles prior melt mixing in order to prevent agglomeration and FT-IR analysis was done to characterize the particles. After melt mixing, particle filled rectangular plates were obtained by plastic injection molding and antibacterial tests were done on the plates according to a standard method, JIS Z 2801. According to the results, satisfactory antibacterial properties were obtained for both polymers and it has been seen that particles without silane could not provide antibacterial effect.

12

AFM Investigation of Biological Nanostructures

63%

Strzelecki J., Dąbrowski M., Strzelecka J., Tszydel M., Mikulska K., Nowak W., Balter A.

Acta Physica Polonica A

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2012

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vol. 122

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issue 2

329-332

EN

Nanostructures created by living organisms, optimized through millions of years of evolution, can be a valuable inspiration for nanotechnology. We employ atomic force microscopy to examine such structures in materials created by common organisms - caddisfly and diatoms. Caddisfly larvae are well known for their ability to spin silk, which serves as an "adhesive tape" to glue various materials and collect food in aqueous environment. Atomic force microscopy imaging of caddisfly silk, performed for the first time by our team, has shown that its surface is patterned with 150 nm extensions - a feature related to its exceptional underwater sticking abilities. Results of force spectroscopy of protein structures found on the surface are also shown. A characteristic feature of diatoms is that they are encased within a unique silica cell wall called frustules, patterned with 200 nm pores, which allow cellular interaction with the environment. We perform atomic force microscopy imaging of frustules in living diatoms as well as adhesion measurements inside pores.

13

Photoluminescence Studies of Aluminum Nitride Nanowires

63%

Yang J., Na H., Kim H., Kebede M., Choi R., Jeong J., Lee C., Kim H.

Acta Physica Polonica A

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2011

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vol. 119

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issue 2

125-127

EN

We report the production of AlN nanowires by the thermal heating method, for exploring their photoluminescence properties. The room-temperature photoluminescence properties were investigated with different annealing environment. While broad emissions with peaks at around 2.45 and 2.95 eV were obtained from both unannealed and annealed samples, the additional 2.1 eV peak was found from the annealed samples. We have suggested the possible emission mechanisms based on the assumption that both 2.45 eV peak and 2.1 eV peak are ascribed to the nitrogen vacancies. Annealing in N_2 environment exhibited lower intensities of 2.45 eV peak and 2.1 eV peak in comparison to those in Ar environment, presumably due to the suppression of nitrogen vacancies.

14

La-Based Material for Energy Storage Applications

63%

Atalay F., Kaya H., Bingol A., Asma D.

Acta Physica Polonica A

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2017

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vol. 131

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issue 3

453-456

EN

In this work, nanostructured La-based materials were produced by chemical precipitation method onto Cladosporium cladosporioides fungal hyphae in aqueous solution. Materials were annealed at various temperatures between 100°C-600°C. The morphological properties of the synthesized material were studied by transmission electron microscopy. The surface area for sample annealed at 360°C was determined to be 85.64 m²/g using Brunauer-Emmett-Teller method. The nitrogen adsorption and desorption isotherm displayed a typical type-IV isotherm. Electrochemical properties of produced material were studied using cyclic voltammetry, long term charge/discharge analysis and impedance spectroscopy in the 0.5 M Na₂SO₄ electrolyte. The obtained nanostructured porous electrode exhibits quasi-rectangular shaped cyclic voltammetry curves with a specific capacitance of 2190 F/g at a scan rate of 2 mV/s.

15

Mechanochemical Synthesis of Silver Chloride Nanoparticles by a Dilution Method in the System NH_4Cl-AgNO_3-NH_4NO_3

63%

Tatykaev B., Burkitbayev M., Uralbekov B., Urakaev F.

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vol. 126

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issue 4

1044-1048

EN

This study presents the results of the synthesis of silver chloride nanoparticles dispersed within ammonium nitrate matrix via displacement mechanochemical reaction NH_{4}Cl + AgNO_{3} + zNH_{4}NO_{3} = (z+1)NH_{4}NO_{3} + AgCl at z = z_{1}= 7.22 and z = z_{2}= 3.64. The intermediate compound, NH_{4}Ag(NO_{3})_{2}, was identified after mechanochemical processing of studied system. Use of simultaneous thermogravimetry and differential scanning calorimetry provide a new means for preparing silver chloride nanoparticles in their free form by thermal treatment.

16

Fabrication and Physical Properties of SiC-GaAs Nano-Composites

63%

Kalisz G., Grzanka E., Wasik D., Świderska-Środa A., Gierlotka S., Borysiuk J., Kamińska M., Twardowski A., Pałosz B.

Acta Physica Polonica A

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2005

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vol. 108

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issue 4

717-721

EN

Nano-composites consisting of primary phase of hard nanocrystalline SiC matrix and the secondary nanocrystalline semiconductor (GaAs) phase were obtained by high-pressure zone infiltration. The synthesis process occurs in three stages: (i) at room temperature the nanopowder of SiC is compacted along with GaAs under high pressure up to 8 GPa, (ii) the temperature is increased above the melting point of GaAs up to 1600~K and, the pores are being filled with liquid, (iii) upon cooling GaAs nanocrystallites grow in the pores. Synthesis of nano-composites was performed using a toroid-type high-pressure apparatus (IHPP of the Polish Academy of Sciences, Warsaw) and six-anvil cubic press (MAX-80 at HASYLAB, Hamburg). X-ray diffraction studies were performed using a laboratory D5000 Siemens diffractometer. Phase composition, grain size, and macrostrains present in the synthesized materials were examined. Microstructure of the composites was characterized using scanning electron microscopy and high resolution transmission electron microscopy. Far-infrared reflectivity measurements were used to determine built-in strain.

17

The Topographic Peculiarities of the Formation of Nanosized Particles from Metallopolymers

63%

Pomogailo A., Dzhardimalieva G., Rosenberg A.

Acta Physica Polonica A

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2002

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vol. 102

|

issue 1

135-145

EN

The morphology of solid phase products of thermal transformation of transition metal acrylates or its cocrystallites is studied. The thermal transformation of the metal-containing monomers studied consists in dehydration, solid phase polymerization and thermolysis process. The topography of the initial compounds and solid phase products of thermal decay, as well as their composition, are analyzed by optical and electron microscopies. The average particle sizes, d_{EM}, are: 6.0-13.0 nm in the case of FeAcr_6 (based on the data of electron diffraction, the main product is Fe_3O_4), 6.0 nm for FeCoAcr_8 and Fe_2CoAcr_{14} (Fe_3O_4, CoO, Fe_2CoO_4), and 6 nm for CoMal_2 (CoO). The material formed consists of nanosized metal particles uniformly allotted in polymer matrix.

18

Study of Ga_2O_3 Nanobelts Synthesized by the Thermal Annealing of GaN Powders

63%

Kim H., Kim N.

Acta Physica Polonica A

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2005

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vol. 107

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issue 2

346-350

EN

We synthesized the uniform monoclinic gallium oxide (Ga_2O_3) nanobelts by a simple thermal annealing of GaN powders. The as-syn-thesized nanobelts were rectangular in cross-sectional shape with width ranging from 100 to 700 nm. The length direction of the nanobelt was along [010]. Photoluminescence measurement under excitation at 325 nm showed that the Ga_ 2O_3 nanobelts had a blue emission at around 454 nm.

19

Synthesis of Fe_4[Fe(CN)_6]_3·14H_2O Nanopowder by Co-Precipitation Technique and Effect of Heat Treatment

51%

Rohilla S., Lal B., Sunder S., Aghamkar P., Kumar S., Aggarwal A.

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issue 4

696-700

EN

Nanopowder of iron cyanide hydrate (member of Prussian blue family) was obtained using ferric chloride and potassium cyanide in their dilute solution through co-precipitation method. The effect of thermal annealing on iron cyanide hydrate nanocrystallites have been studied in detail. The formation of Fe_4[Fe(CN)_6]_3·14H_2O and iron oxides was revealed by the Fourier transform infrared spectroscopy. The crystal structure, morphology and size of nanocrystallites were investigated by X-ray diffraction and transmission electron microscope. Results suggest that using co-precipitation technique, nanopowder of iron cyanide hydrate, in typically spherical shape, can be obtained and their thermal treatment also yield iron oxide nanocrystallites of spherical with good homogeneity. The size of the prepared nanocrystallites was found in the range 20-36 nm. It was observed that thermal treatment, typically at 800°C (4 h), iron cyanide hydrate (Fe_4[Fe(CN)_6]_3·14H_2O) nanocrystallites transformed into iron oxide (α-Fe_2O_{3,} hematite) nanocrystallites.

20

Gold Nanoparticles with Elongated Shapes: Synthesis and Optical Properties

51%

Olejnik M., Agarwal A., Zaleszczyk W., Kotov N., Mackowski S.

Acta Physica Polonica A

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2012

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vol. 122

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issue 2

346-349

EN

We use a seed-mediated growth to fabricate gold nanorods in water solution. By changing the amount of silver salt we demonstrate the control of aspect ratio of the obtained rods. The microscopic and spectroscopic analyses provide ways to characterize the morphology and the optical properties of the gold nanorods. Nanorods synthesized using this approach feature length of the order of 50-60 nm, which translates into longitudinal plasmon resonances in the near infrared spectrum region.

Refine search results

Synthesis of Silver Halide Nanosols

Fabrication and Characterization of AgNPs Incorporated PVA/ODA-MMT and PVP/ODA-MMT Nanofiber Structures by Green Electrospinning Nanotechnology as Excellent Conducting and Bioengineering Nanomaterial

Carbon Nanomaterials from Carbon Monoxide Using Nickel and Cobalt Catalysts

Preparation and Characterization of Two-Dimensional Ordered Arrays of Metallic Nanoparticles

Synthesis, Structure, Photoluminescence, and Raman Spectrum of Indium Oxide Nanowires

SiO_x Nanowires Produced on Molybdenum-Coated Si Substrates

Catalyst-Free Growth of Magnesium Oxide Whiskers and Their Characteristics

Modifications in Near-Surface Layer of Transparent Dielectrics Ionized by Ultrashort Laser Pulses

Characteristic Properties of Dy-Eu-Ce Co-Doped ZrO₂ Nanofibers Fabricated via Electrospinning

Preparation, Study and Nanoscale Growth of Indium Oxide Thin Films

Comparison of Antibacterial Properties of Nano TiO_2 and ZnO Particle Filled Polymers

AFM Investigation of Biological Nanostructures

Photoluminescence Studies of Aluminum Nitride Nanowires

La-Based Material for Energy Storage Applications

Mechanochemical Synthesis of Silver Chloride Nanoparticles by a Dilution Method in the System NH_4Cl-AgNO_3-NH_4NO_3

Fabrication and Physical Properties of SiC-GaAs Nano-Composites

The Topographic Peculiarities of the Formation of Nanosized Particles from Metallopolymers

Study of Ga_2O_3 Nanobelts Synthesized by the Thermal Annealing of GaN Powders

Synthesis of Fe_4[Fe(CN)_6]_3·14H_2O Nanopowder by Co-Precipitation Technique and Effect of Heat Treatment

Gold Nanoparticles with Elongated Shapes: Synthesis and Optical Properties