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1
Content available Nanoparticles, Synthesis Methods and Applications - A Simple Review
100%
Nwakanma U. G. , Elemike E. E.
World News of Natural Sciences
|
2023
|
tom 47
48-60
EN
Nanotechnology has gained so much interest in today’s world. It is known to be the science of nanoscales which is less than 100 nanometre in size. This technology has been employed for different applications due to its eco-friendly and sustainable ability in the various fields of applications. Recently, nanotechnology is used in bio sensing, drug delivery, nano devices, separation and purification purposes. These nanoparticles which are used in the building blocks of many materials, and the synthesis methods vary for all due to their physical and chemical properties. This study attempts to review the field of nanotechnology, synthesis of nanoparticles, the properties of nanoparticles, the advantages and disadvantages of different methods and their applications.
2
Content available remote Systematic investigation and in vitro biocompatibility studies on mesoporous europium doped hydroxyapatite
100%
Popa C. , Ciobanu C. , Iconaru S. , Stan M. , Dinischiotu A. , Negrila C. , Motelica-Heino M. , Guegan R. , Predoi D.
Open Chemistry
|
2014
|
tom 12
|
nr 10
1032-1046
EN
This paper reports the systematic investigation of europium doped hydroxyapatite (Eu:HAp). A set of complementary techniques, namely Fourier Transform Infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and the Brunauer-Emmett-Teller (BET) technique were used towards attaining a detailed understanding of Eu:HAp. The XPS analysis confirmed the substitution of Ca ions by Eu ions in the Eu:HAp samples. Secondly, Eu:HAp and pure HAp present type IV isotherms with a hysteresis loop at a relative pressure (P/P0) between 0.4 and 1.0, indicating the presence of mesopores. Finally, the in vitro biological effects of Eu:HAp nanoparticles were evaluated by focusing on the F-actin filament pattern and heat shock proteins (Hsp) expression in HEK293 human kidney cell line. Fluorescence microscopy studies of the actin protein revealed no changes of the immunolabelling profile in the renal cells cultured in the presence of Eu:HAp nanoparticles. Hsp60, Hsp70 and Hsp90 expressions measured by Western blot analysis were not affected after 24 and 48 hours exposure. Taken together, these results confirmed the lack of toxicity and the biocompatibility of the Eu:HAp nanoparticles. Consequently, the possibility of using these nanoparticles for medical purposes without affecting the renal function can be envisaged.
3
Content available remote Influence of heat treatment on the phase transition of ZrMo2O8 and photocatalytic activity
100%
Mancheva M. , Iordanova R. , Dimitriev Y. , Tyuliev G. , Iliev T.
Open Chemistry
|
2011
|
tom 9
|
nr 3
460-465
EN
ZrMo2O7(OH)2·2H2O was obtained from ZrOCl2·2H2O and Na2MoO4·2H2O by a coprecipitation method. The phase and structural changes occurred during the heat-treatment of ZrMo2O7(OH)2·2H2O were investigated by XRD, IR and XPS analysis. The sequence of phase transformation can be divided into three stages: (1) transformation of ZrMo2O7(OH)2·2H2O to orthorhombic LT-ZrMo2O8 up to 300°C; (2) obtaining of mixture of both polymorphs of ZrMo2O8: cubic and trigonal at 400°C; (3) conversion to single trigonal (α) ZrMo2O8 above 450°C. The microstructure of the obtained trigonal (α) ZrMo2O8 was observed by scanning electron microscopy (SEM). The particle sizes were below 0.5 µm. The specific surface area was measured by modified BET method. The photocatalytic activity of the obtained trigonal (α) ZrMo2O8 powders was investigated by degradation of a model aqueous solution of Malachite Green (MG) upon UV-light irradiation.
4
Content available remote A review on the synthesis of TiO2 nanoparticles by solution route
100%
Gupta S. , Tripathi M.
Open Chemistry
|
2012
|
tom 10
|
nr 2
279-294
EN
TiO2 can be prepared in the form of powder, crystals, or thin films. Liquid-phase processing is one of the most convenient and utilized methods of synthesis. It has the advantage of allowing control over the stoichiometry, production of homogeneous materials, formation of complex shapes, and preparation of composite materials. However, there may be some disadvantages such as expensive precursors, long processing times, and the presence of carbon as an impurity. In comparison, the physical production techniques, although environment friendly, are limited by the size of the produced samples which is not sufficient for a large-scale production. The most commonly used solution routes in the synthesis of TiO2 are reviewed.
5
Content available remote Development of FeOOH nanoarrays using magnetic cations
88%
Garcia-Casillas P. , Martinez-Pérez C. , González C. , Camacho-Montes H. , Martel Estrada S. , Armendáriz I.
Open Chemistry
|
2013
|
tom 11
|
nr 3
358-363
EN
Abstract In this work, FeOOH arrays were obtained using two different magnetic cations. The nanoparticles were grouped into a package having different orientations through the van der Waals interaction with the magnetic cations. With Fe2+, the FeOOH nanoparticles have a rod shape with a 30-nm diameter and approximately 1-micron length, and are aligned in a star structure. With Co2+, a somatoidal shape was observed, with 20-nm diameter and 150-nm length and a pathway structure to the array. The chemical synthesis method was used to obtain the nanoarrays. The morphology and the average size of the nanorods and nanowires were determined using Field Emission Scanning Electron Microscopy (FESEM). Fourier Transform Infrared Spectroscopy (FTIR) was used to study the interaction between the nanorods and the cobalt ions. The phases of the material were identified using X-ray Diffraction. Graphical abstract [...]
6
Content available remote Aminophosphine complex as a catalyst precursor in Suzuki coupling reactions
88%
Zhao D. , Fei Z. , Ang W.
Open Chemistry
|
2008
|
tom 6
|
nr 1
93-98
EN
A palladium complex with an aminophosphine ligand has been prepared and investigated as a catalyst precursor in Suzuki coupling reactions in toluene. Nanoparticles composed of elemental palladium have been isolated from the reaction media and analyzed using transmission electroscopic microscope (TEM), which shows the essential catalysts palladium nanoparticles to have a size of ca. 3.0 nm. [...]
7
Content available remote Comparison of stability properties of poly(acrylic acid) adsorbed on the surface of silica, alumina and mixed silica-alumina nanoparticles - application of turbidimetry method
88%
Wiśniewska M. , Urban T. , Nosal-Wiercińska A. , Zarko V. , Gun’ko V.
Open Chemistry
|
2014
|
tom 12
|
nr 4
476-479
EN
The influence of anionic poly(acrylic acid) - PAA addition on the stability of synthesized silica, alumina and mixed silica-alumina suspensions as a function of solution pH was studied. The turbidimetry method was used to monitor the changes of the examined systems stability over time. The calculated stability coefficients enabled estimation of polymer adsorption influence on stability of metal oxide suspension. It was shown that the alumina suspension without the polymer is the most unstable at the pH values 6 and 9, whereas the silica polymer was most unstable at pH 3. PAA with higher molecular weight (240 000) is a relatively effective stabilizer of all investigated adsorbents (except silica at pH 3). These properties of poly(acrylic acid) are highly desirable in many branches of industry (e.g. production of cosmetics, pharmaceuticals, paints) where polymers are widely used as effective stabilizers of colloidal suspensions.
8
Content available remote Capillary electrophoretic separation and characterizations of CdSe quantum dots
88%
Oszwałdowski S. , Zawistowska K. , Grigsby L. , Roberts K.
Open Chemistry
|
2010
|
tom 8
|
nr 4
806-819
EN
We have developed a capillary electrophoresis method to characterize the QD surface ligand interactions with various surfactant systems. The method was demonstrated with 2–5 nm CdSe nanoparticles surface-passivated with trioctylphosphine oxide (TOPO). Water solubility was accomplished by surfactant-assisted phase transfer via an oil-in-water microemulsion using either cationic, anionic, or non-ionic surfactants. Interaction between the QD surface ligand (TOPO) and the alkyl chain of the surfactant molecule produces a complex and dynamic surface coating that can be characterized through manipulation of CE separation buffer composition and capillary surface modification. Additional characterization of the QD surface ligand interactions with surfactants was accomplished by UV-VIS spectroscopy, photoluminescence, and TEM. It is anticipated that studies such as these will elucidate the dynamics of QD surface ligand modifications for use in sensors. [...]
9
Content available remote The Synthesis of a Luminescent Plasmonic Nanomaterial
88%
Hashim Z. , Green M.
NanoBioImaging
|
2014
|
tom 1
|
nr 1
EN
Gold nanoparticles were synthesised in toluene and stabilised by a fluorescent conjugated polymer (F8BT). The gold/conjugated polymer nanoparticles system was also found to be stable in dichloromethane (DCM), exhibiting both fluorescence (quantum yield = 14%) and a surface plasmon in organic solvents
10
Content available Diversified role and applications of marine actinomycetes in the field of biology
88%
Rasool U. , Hemalatha S.
World Scientific News
|
2017
|
tom 74
1-14
EN
Actinomycetes are the most profitable and biotechnologically valued prokaryotes representing the genera consisting of Streptomyces, Arthrobacter, Actinomyces, Cornyebacterium, Micrococcus, Micromonospora and other diverse species of microorganisms. Actinomycetes represent a group of one of the most powerful secondary metabolite producers which possess a wide range of biological activities. Streptomyces, an important genus under actinomycetes, alone serves as the huge producer of a number of biologically active molecules. This genus possesses a huge potential of synthesizing various different and novel active metabolites. Due to the gradual reduction of the chances of isolation of novel compounds within Streptomyces coming from terrestrial environs resulting in the increase of resistant pathogenic microorganisms, marine actinomycetesmay form a platform for novel drug synthesis, which in-turn may form an extraordinary tool for combating a wide range of resistant microbes. The role of marine actinomycetes extends to diverse fields such as antibiotic production, production of antibacterial and antifungal compounds, synthesis of enzymes and enzyme inhibitors, synthesis of anticancer drugs and various other lifesaving molecules. Marine actinomycetes also play an important role in biofouling and nanoparticle synthesis. Thus speakingsuccinctly, marine actinomycetes are biologically very important as they serve their useful purpose in various fields of biology.
11
Content available Improved photoresponse of porous silicon photodetectors by embedding CdS nanoparticles
75%
Abd A. N.
World Scientific News
|
2015
|
tom 19
32-49
EN
In this research, the nanocrystalline porous silicon (PSi) films are prepared by electrochemical etching of p types silicon wafers with 15 mA/cm2 etching current densities and 15 min etching time on the formation nanosized pore array. PSi was characterized by the measurement of XRD, FTIR spectroscopy and atomic force microscopy properties (AFM). We have estimated crystallites size from X-Ray diffraction about nanoscale for PSi and Atomic Force microscopy confirms the nanometric size Chemical fictionalization during the electrochemical etching show on the surface chemical composition of PSi. The atomic force microscopy investigation shows the rough silicon surface. Also, it is reported the preparation of colloidal CdS nanoparticles NPs prepared by laser ablation in liquid (LAL) technique by irradiating with a Nd:YAG laser pulses CdS target immersed in methanol and varying the laser fluence 1.32 J/cm2. The structural, morphological and optical of CdS NPs has been studied. XRD measurement disclosed that the CdS NPs were of wurtzite hexagonal crystal structure. Transmission electron microscopy (TEM) investigation revealed that the synthesized CdS particles are spherical and have an average particle size in the range of (25 nm). AFM investigations showed that the produced CdS particles have ball-shape with good disposability. The energy band gap of CdS NPs prepared with 1.32 J/cm2 laser fluence has been determined from optical properties and found to be in the range (2.9 eV). Optical constants of CdS NPs were determined from transmittance and reflectance spectra.The effect of CdS NPs diffusion on properties of PSi Photodetector have reported which reveals that improving in (Al/PSi/Si/Al). The results show that a linear relationship between 1/C2 and reverse bias voltage was obtained. The built-in potential have values depending on the etching time current density and laser flunce. Al/CdSe/PSi/Si/Al photodetector hetrojunction have two peaks of response located at 415 nm and (700 -800nm) with max sensitivity  0.6 A/W. The maximum specific detectivity is 6.8×〖10〗^12 cm•〖Hz〗^(1/2) 〖•W〗^(-1) at  770 nm wavelength.
12
Content available Hydrothermal Synthesis of Highly Uniform Chalcopyrite CuFeS2 Nanoparticles
75%
Sabet M. , Mahdavi K. , Salmeh F. , Sabet M. , Mahdavi K. , Salmeh F.
|
|
tom 65
|
nr 2
13
Content available remote Patterning of Quantum Dots by Dip-Pen and Polymer Pen Nanolithography
75%
Biswas S. , Brinkmann F. , Hirtz M. , Fuchs H.
Nanofabrication
|
2015
|
tom 2
|
nr 1
EN
We present a direct way of patterning CdSe/ ZnS quantum dots by dip-pen nanolithography and polymer pen lithography. Mixtures of cholesterol and phospholipid 1,2-dioleoyl-sn-glycero-3 phosphocholine serve as biocompatible carrier inks to facilitate the transfer of quantum dots from the tips to the surface during lithography. While dip-pen nanolithography of quantum dots can be used to achieve higher resolution and smaller pattern features (approximately 1 μm), polymer pen lithography is able to address intermediate pattern scales in the low micrometre range. This allows us to combine the advantages of micro contact printing in large area and massive parallel patterning, with the added flexibility in pattern design inherent in the DPN technique.
14
Content available remote A green chemical route for the synthesis of Mn3O4 nanoparticles
75%
Durmus Z. , Kavas H. , Baykal A. , Toprak M.
Open Chemistry
|
2009
|
tom 7
|
nr 3
555-559
EN
A novel environmental friendly, room temperature route using an ionic liquid 1-n-butyl-3-methylimidazolium hydroxide ([BMIM]OH) for the synthesis of Mn3O4 nanoparticles is presented. The product was characterized using Fourier transform infrared spectroscopy, X-ray powder diffraction, and transmission electron microscopy. Phase purity was confirmed by XRD, and X-ray line profile fitting determined a crystallite size of 42 ± 11 nm. TEM analysis revealed various morphologies. EPR measurements have indicated the existence of long-range interactions, due to the wide range of particle sizes and morphologies observed. [...]
15
Content available remote Influence of ion bombardment on the photoluminescence response of embedded CdS nanoparticles
63%
Mohanta D. , Singh F. , Avasthi D. , Choudhury A.
Open Physics
|
2006
|
tom 4
|
nr 2
187-195
EN
Semiconductor nanoparticles (CdS) were fabricated by an inexpensive chemical route using polyvinyl alcohol (PVA) as the dielectric host matrix. Nano-CdS in PVA were subjected to ion irradiation (using oxygen, chlorine and gold) in the medium energy range (80–100 MeV) and under fluence variation of 1011–1013 ions/cm2. The nature of light emission was found to be drastically different in each of the three cases. Photoluminescence spectra of oxygen irradiated samples exhibit band edge emission (2.8 eV) as well as trap related emission (1.76 eV) whereas band edge emission is found to be bleached out for chlorine ion irradiated nano-CdS. The intense broad PL peaks, noticeable in the case of gold ion irradiated samples suggest superposition of the two peaks - namely, band edge emission and trap related emission. Furthermore, in the case of gold ion irradiated nano-CdS, energy shift in the PL spectra reveals variation in size distribution caused by the extra pressure effect of heavy gold ion beams. The mechanism of such a difference as a result of ion irradiation-type and ion-fluence is discussed in detail.
16
Content available Nanocomposites Based on Water Glass Matrix as a Foundry Binder: Chosen Physicochemical Properties
63%
Kmita A. , Roczniak A.
|
|
tom 17
|
nr 1
17
Content available Interaction of novel lubricant additives based on MoS2 nanotubes with non-ferrous tribological materials
51%
Tomala A. M. , Michalczewski R. , Osuch-Słomka E.
Tribologia
|
2018
|
tom nr 4
127--135
EN
MoS2 nanotubes (NTs) are novel lubricant additives reducing friction and wear of mechanical components made of steel. Nowadays, non-ferrous surfaces are becoming more widely used, mainly as multifunctional coatings working in configuration with a steel pair. As a consequence, the purpose of this work is to reveal the interaction mechanism of nanoparticles with coated elements in lubricated contacts that are essential in future lubrication technologies. The tribological properties were investigated using a reciprocating sliding testing machine in a steel-ball-on-coated-disc configuration. For tribological studies, two commercially available coatings were selected: WC/C and DLC coating. Frictional results show only slight improvement for lubricant blends containing MoS2 nanotubes with selected coatings, and wear tracks are surprisingly very extensive when compare to oils with additives. Generally, the presence of coating in any tribological test configurations diminish the effectiveness of MoS2 NTs when compare to steel/steel contact. Chemical analytics show that interaction mechanisms of the nanotubes and surface changes, depending on the coating material, have the ability to form a chemically derived tribofilm.
PL
Nanorurki MoS2 są innowacyjnym dodatkiem do środków smarowych redukującym tarcie oraz zużycie stalowych elementów maszyn. Mechanizm ich działania w skojarzeniach elementów stalowych jest stosunkowo dobrze poznany i opisany. Obecnie coraz częściej na elementy maszyn stosowane są materiały nieżelazne, w tym niskotarciowe cienkie powłoki przeciwużyciowe. Brak obecności tlenków żelaza na powierzchniach trących determinuje zmianę charakteru oddziaływania nanocząsek z powierzchnią. Celem pracy jest opis oddziaływania środków smarowych z dodatkiem nanocząsteczek MoS2 w skojarzeniach tribologicznych z powierzchniami elementów pokrytych powłokami typu DLC. Badania tribologiczne zostały zrealizowane z wykorzystaniem stanowiska SRV pracującego w warunkach ruchu oscylacyjnego, w którym węzeł tarcia stanowi stalowa kulka oraz tarcza pokryta powłoką niskotarciową. W badaniach stosowano powłoki typu WC/C i DLC. Stwierdzono, że zastosowanie niskotarciowych powłok na tarczach zmniejszyło efektywność działania nanorurek MoS2 w porównaniu ze skojarzeniem elementów stalowych bez powłoki. Odnotowano nieznaczną poprawę współczynnika tarcia dla skojarzeń smarowanych olejem zawierających nanorurki MoS2, jednakże zużycie elementów trących było znacznie większe niż uzyskiwane dla olejów bez dodatku nanorurek. Analiza chemiczna wykazała, że mechanizmy oddziaływania nanorurek i materiału powierzchni tarcia zmieniają się w zależności od materiału elementów trących, biorącego udział tworzeniu tribochemicznej warstwy granicznej.
18
Content available Implementation of Nanoparticles in Materials Applied in Foundry Engineering
50%
Kmita A. , Roczniak A.
|
|
tom 17
|
nr 3
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