Biosynthesis of Self-Dispersed Silver Colloidal Particles Using the Aqueous Extract of P. peruviana for Sensing dl-Alanine

We report the biosynthesis of silver nanoparticles (AgNPs) in a single step using edible fruit aqueous extract of P. peruviana that essentially involved the concept of green chemistry. Yellowish-brown color appeared upon adding the broth of P. peruviana to aqueous solution of 1 mM AgNO3 which indicates the formation of AgNPs. The maximum synthesis of these nanoparticles was being achieved in nearly 2 hrs at 28°C. The synthesis of AgNPs was followed by AgNPs UV-visible spectroscopy. Particle size and morphology of AgNPs were studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), respectively. These studies revealed that the AgNPs characterized were spherical in shape with diameter ranging from 31 to 52 nm. The energy dispersive X-ray spectroscopy showed that the AgNPs present are approximately 63.42 percent by weight in the colloidal dispersion. The absorption spectra of the AgNPs in absence and presence of dl-alanine show a distinguish shift in surface plasmon resonance (SPR) bands. Thus, these nanoparticles may be used as a chemical sensor for dl-alanine present in the human blood.

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Solvothermal Synthesis and Characterization of Lithium Tantalate Nanoparticles

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.602-603.19 ◽

2014 ◽

Vol 602-603 ◽

pp. 19-22 ◽

Cited By ~ 1

Author(s):

Lin Qiang Gao ◽

Hai Yan Chen ◽

Zhen Wang ◽

Xin Zou

Keyword(s):

Electron Microscopy ◽

Solvothermal Synthesis ◽

Room Temperature ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Particle Size And Morphology ◽

Size And Morphology

Nanoscale LiTaO3 powders with perovskite structure were synthesized using the solvothermal technique with glycol as solvent at 240°C for 12h. The powders were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). XRD was used to elucidate room temperature structures using Rietveld refinement. The powders were pure single pervoskite phase with high crystallinity. FESEM and TEM were used to determine particle size and morphology. The average LiTaO3 grain size was estimated to be < 200nm, and TEM images indicated that LiTaO3 particles had a brick-like morphology. In addition, the effect of the temperature on the LiTaO3 power characterisitics was also detailed studied.

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Preparation of Nanocellulose Using Ionic Liquids: 1-Propyl-3-Methylimidazolium Chloride and 1-Ethyl-3-Methylimidazolium Chloride

Molecules ◽

10.3390/molecules25071544 ◽

2020 ◽

Vol 25 (7) ◽

pp. 1544 ◽

Cited By ~ 1

Author(s):

Marta Babicka ◽

Magdalena Woźniak ◽

Krzysztof Dwiecki ◽

Sławomir Borysiak ◽

Izabela Ratajczak

Keyword(s):

Electron Microscopy ◽

Ionic Liquids ◽

Microcrystalline Cellulose ◽

Crystallinity Index ◽

X Ray Diffraction ◽

Cellulose I ◽

Transmission Electron ◽

Cation Type ◽

Particle Size And Morphology ◽

Size And Morphology

Cellulose nanocrystals were prepared using ionic liquids (ILs), 1-ethyl-3-methylimidazolium chloride [EMIM][Cl] and 1-propyl-3-methylimidazolium chloride [PMIM][Cl], from microcrystalline cellulose. The resultant samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The XRD results showed that nanocellulose obtained by treatment with both ILs preserved basic cellulose I structure, but crystallinity index of samples (except for Sigmacell treated with [EMIM][Cl]) was lower in comparison to the starting microcrystalline cellulose. The DLS results indicated noticeably smaller particle sizes of prepared cellulose for material treated with [PMIM][Cl] compared to cellulose samples hydrolyzed with [EMIM][Cl], which were prone to agglomeration. The obtained nanocellulose had a rod-like structure that was confirmed by electron microscopy analyses. Moreover, the results described in this paper indicate that cation type of ILs influences particle size and morphology of cellulose after treatment with ionic liquids.

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Synthesis of Macroporous FeS2 Nanotubes and their Electrochemical Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.774-776.677 ◽

2013 ◽

Vol 774-776 ◽

pp. 677-681

Author(s):

Han Tao Liao ◽

You Rong Wang ◽

Jia Wang ◽

Xiao Fang Qian ◽

Si Qing Cheng

Keyword(s):

Electron Microscopy ◽

Electrochemical Properties ◽

X Ray Diffraction ◽

Capacity Retention ◽

One Pot ◽

X Ray ◽

Transmission Electron ◽

Particle Size And Morphology ◽

Size And Morphology ◽

First Time

The particle size and morphology have a strong influence on the electrochemical performance of FeS2electrodes. In this paper, a simple one-pot solvothermal method is reported for the synthesis of macroporous pyrite nanotubes for the first time. The phase composition, morphology and structure of the as-obtained products were studied by the energy dispersive spectroscopy (EDS), scanning electron microscopy, (high-resolution) transmission electron microscopy, X-ray diffraction. The electrochemical properties of the FeS2samples were also investigated. The results demonstrated that the macroporous pyrite nanotubes delivered a higher initial discharge capacity of 925.2 mAh g-1and had good capacity retention.

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Preparation of Silver Nanoparticles in Poly(N-vinylpyrrolidone)/Ethanol Solutions

International Journal of Nanoscience ◽

10.1142/s0219581x17500089 ◽

2017 ◽

Vol 16 (05n06) ◽

pp. 1750008 ◽

Cited By ~ 1

Author(s):

Shu Zhang ◽

Yongan Tang ◽

Branislav Vlahovic

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Silver Nitrate ◽

Weight Ratio ◽

Plasmon Resonance Peak ◽

X Ray ◽

Transmission Electron ◽

Particle Size And Morphology ◽

Size And Morphology ◽

Average Size

Silver nanoparticles have been synthesized from Poly(N-vinylpyrrolidone) (PVP)/ethanol solutions, and six different PVP to silver nitrate weight ratios (PVP:AgNO3) are studied in reduction of silver nitrate in ethanol with the presence of PVP as a stabilizer. The produced silver nanoparticles showed strong plasmon resonance peak centered at around 405[Formula: see text]nm in UV-Vis spectra. The particle morphologies were also examined and compared under secondary electron microscopy (SEM) and transmission electron microscopy (TEM). Energy dispersion X-ray spectroscopy (EDX) was utilized to determine the formation of silver nanoparticles. We found that the particle size and morphology were strongly dependent on the PVP:AgNO3 weight ratio. The average size of silver particles decreased from 19.25[Formula: see text]nm to 10.03[Formula: see text]nm as the weight ratio of PVP:AgNO3 increased from 1:1 to 20:1.

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Study on Structure, Thermal Behavior, and Viscoelastic Properties of Nanodiamond-Reinforced Poly (vinyl alcohol) Nanocomposites

Polymers ◽

10.3390/polym13091426 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1426

Author(s):

Tomáš Remiš ◽

Petr Bělský ◽

Tomáš Kovářík ◽

Jaroslav Kadlec ◽

Mina Ghafouri Azar ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Analysis ◽

Single Step ◽

Poly Vinyl Alcohol ◽

Scanning Calorimetry ◽

X Ray Scattering ◽

Transmission Electron ◽

Primary Particles ◽

Solution Casting Method ◽

Average Size

In this work, advanced polymer nanocomposites comprising of polyvinyl alcohol (PVA) and nanodiamonds (NDs) were developed using a single-step solution-casting method. The properties of the prepared PVA/NDs nanocomposites were investigated using Raman spectroscopy, small- and wide-angle X-ray scattering (SAXS/WAXS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). It was revealed that the tensile strength improved dramatically with increasing ND content in the PVA matrix, suggesting a strong interaction between the NDs and the PVA. SEM, TEM, and SAXS showed that NDs were present in the form of agglomerates with an average size of ~60 nm with primary particles of diameter ~5 nm. These results showed that NDs could act as a good nanofiller for PVA in terms of improving its stability and mechanical properties.

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Preferential dissolution along misoriented boundaries in heterogenite

MRS Proceedings ◽

10.1557/proc-620-m5.7.1 ◽

2000 ◽

Vol 620 ◽

Author(s):

R. Lee Penn ◽

Alan T. Stone ◽

David R. Veblen

Keyword(s):

Electron Microscopy ◽

Aspect Ratio ◽

Reductive Dissolution ◽

Morphology Evolution ◽

Crystal Chemical ◽

Transmission Electron ◽

Micron Size ◽

Primary Particles ◽

Size And Morphology ◽

Preferential Dissolution

ABSTRACTHigh-Resolution Transmission Electron Microscopy (HRTEM) results show a strong crystal-chemical and defect dependence on the mode of dissolution of synthetic heterogenite (CoOOH) particles. As-synthesized heterogenite particles are micron-size plates (aspect ratio ∼ 1/30) constructed of crystallographically oriented ∼ 3-nm primary particles or are single ∼ 21-nm unattached heterogenite platelets (aspect ratio ∼1/7). Reductive dissolution, using hydroquinone, was examined in order to evaluate morphology evolution as a function of reductant concentration. Two end-member modes of dissolution were observed: 1) non-specific dissolution of macroparticles and 2) preferential dissolution along misoriented boundaries. In the case of non-specific dissolution, average macrocrystal size and morphology are not altered as building block crystals are consumed. The result is web-like particles with similar breadth and shape as undissolved particles. Preferential dissolution involves the formation of channels or holes along boundaries of angular misorientation. Such boundaries involve only a few degrees of tilt, but dissolution occurs almost exclusively at such sites. Energy-Filtered TEM thickness maps show that the thickness of surrounding material is not significantly different from that of undissolved particles. Finally, natural heterogenite from Goodsprings, Nevada, shows morphology and microstructure similar to those of this synthetic heterogenite.

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Synthesis and Characterizations of Nanocubes, Monodispersed Nanocrystals and Nanospheres of Au

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.353-358.2163 ◽

2007 ◽

Vol 353-358 ◽

pp. 2163-2166

Author(s):

Ming Yang ◽

Guo Qing Zhou ◽

Jiang Guo Zhao ◽

Zhan Jun Li

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Powder Diffraction ◽

Visible Absorption ◽

X Ray ◽

Transmission Electron ◽

Uv Visible ◽

Scherrer Formula ◽

Visible Absorption Spectroscopy

Nanocubes, monodispersed nanocrystals and nanospheres of Au have been prepared by a simple reaction between HAuCl4·4H2O, NaOH and NH2OH·HCl in the presence of gelatin. The role of gelatin and the affection of pH in producing the nanoparticles of Au were discussed. The products were characterized by X-ray powder diffraction, transmission electron microscopy, and UV-visible absorption spectroscopy. The sizes of the monodispersed nanocrystals of Au were estimated by Debye-Scherrer formula according to XRD spectrum.

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Preparation of Triangular Silver Nanoparticles Using Polyvinyl Pyrrolidone with Different Concentration

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.873.206 ◽

2013 ◽

Vol 873 ◽

pp. 206-210

Author(s):

Kai Li ◽

Rao Fu ◽

Qing Ran Gao ◽

Ai Wei Tang ◽

Ying Feng Wang

Keyword(s):

Electron Microscopy ◽

Aqueous Solution ◽

Silver Nanoparticles ◽

Driving Force ◽

Ostwald Ripening ◽

Polyvinyl Pyrrolidone ◽

Protective Agent ◽

Ag Nps ◽

Transmission Electron ◽

Uv Visible

This paper continues our previous work on preparation of triangular silver nanoparticles. The method proceeds with reaction of silver nitrate with hydrazine hydrate in the presence of polyvinyl pyrrolidone in aqueous solution. Effects of the concentration of PVP on the morphologies of Ag NPs were systematically investigated. The obtained Ag NPs were characterized by transmission electron microscopy and UV-visible spectrophotometer. The results showed that, triangular Ag NPs with edge lengths in the range of 50-200 nm were obtained using PVP as protective agent with lower concentration. As the concentration of PVP increased, spherical Ag NPs with their sizes about 6.2 nm were prepared and triangular Ag NPs were not obtained. The formation mechanism of triangular Ag NPs has been studied. Ostwald ripening is the driving force on the conversion of spherical Ag NPs to triangular Ag NPs in the presence of PVP.

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Synthesis and Characterization of Calcium Tartrate Dihydrate Nanoparticles

International Journal of Nanoscience ◽

10.1142/s0219581x15500131 ◽

2015 ◽

Vol 14 (04) ◽

pp. 1550013 ◽

Cited By ~ 2

Author(s):

Urvisha Tarpara ◽

Poorvesh Vyas ◽

Mihir J. Joshi

Keyword(s):

Average Crystallite Size ◽

Powder Xrd ◽

Xrd Pattern ◽

Crystalline Materials ◽

Transmission Electron ◽

Calcium Tartrate ◽

Particle Size And Morphology ◽

Wet Chemical ◽

Size And Morphology

Calcium tartrate finds various applications. In the present study, calcium tartrate nanoparticles were synthesized by wet chemical method using surfactant mediated approach. The powder XRD pattern revealed the typical broadening of peaks indicating the nanostructured nature. The average crystallite size was calculated by applying the Scherrer's formula to powder XRD pattern and was found in the range of 22.8–23.9 nm. The particle size and morphology of the synthesized nanoparticles was confirmed by using transmission electron microscopy (TEM). FTIR spectroscopy was used to confirm the presence of various functional groups. From TGA, it was found that calcium tartrate nanoparticles remained stable up to 120°C and were having two water molecules associated with them. The results are compared with the bulk crystalline materials available in the literature.

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Impact of reaction vessel pressure on the synthesis of sliced activated carbon from date palm tree fronds

Hemijska industrija ◽

10.2298/hemind140820078s ◽

2015 ◽

Vol 69 (5) ◽

pp. 561-565 ◽

Cited By ~ 5

Author(s):

Muhammad Shoaib ◽

Hassan Al-Swaidan

Keyword(s):

Electron Microscopy ◽

Flow Rate ◽

Activated Carbons ◽

Single Step ◽

Reaction Vessel ◽

Bet Surface Area ◽

Palm Tree ◽

Surface Areas ◽

Transmission Electron ◽

Co2 Flow

The effects of the reaction vessel pressure on the BET surface area, pore volume and pore size of the synthesis of sliced activated carbons (SAC) at 850?C starting from 0.10 to 0.40 bars were investigated. Other synthetic variables like dwell time, CO2 flow rate and heating ramp rate were kept constant during the whole study. Methodology involves a single step procedure using the mixture of gases (N2 and CO2). During activation flow rate of both gases are kept at 150 and 50ml/min respectively. The BET surface areas of the SAC prepared at 0.10, 0.15, 0.20, 0.25, 0.30, 0.35 and 0.40 bar after 30 minutes activation time are 666, 745, 895, 1094, 835, 658 and 625 m2/g, respectively. Scanning electron microscopy (SEM) for surface morphology, Energy dispersive spectroscopy (EDS), Transmission electron microscopy (TEM) for nano particle size were also carried out that also confirms the same trend.

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