scholarly journals Assessment of Serpentine Group Minerals in Soils: A Case Study from the Village of San Severino Lucano (Basilicata, Southern Italy)

Fibers ◽  
2019 ◽  
Vol 7 (2) ◽  
pp. 18 ◽  
Author(s):  
Rosalda Punturo ◽  
Claudia Ricchiuti ◽  
Andrea Bloise
Keyword(s):  
Health Hazard ◽  
Environmental Pollutants ◽  
Scanning Calorimetry ◽  
Fibrous Minerals ◽  
Transmission Electron ◽  
Generic Term ◽  
Naturally Occurring Asbestos ◽  
The Village

Naturally occurring asbestos (NOA) is a generic term used to refer to both regulated and un-regulated fibrous minerals when encountered in natural geological deposits. These minerals represent a cause of health hazard, since they have been assessed as potential environmental pollutants that may occur both in rocks and derived soils. In the present work, we focused on the village of San Severino Lucano, located in the Basilicata region (southern Apennines); due to its geographic isolation from other main sources of asbestos, it represents an excellent example of hazardous and not occupational exposure of population. From the village and its surroundings, we collected eight serpentinite-derived soil samples and carried out Differential Scanning Calorimetry (DSC), Derivative Thermogravimetric (DTG) and Transmission Electron Microscopy with Energy Dispersive Spectrometry (TEM-EDS), in order to perform a detailed characterization of serpentine varieties and other fibrous minerals. Investigation pointed out that chrysotile and asbestos tremolite occur in all of the samples. As for the fibrous but non-asbestos classified minerals, polygonal serpentine and fibrous antigorite were detected in a few samples. Results showed that the cultivation of soils developed upon serpentinite bedrocks were rich in harmful minerals, which if dispersed in the air can be a source of environmental pollution.

Characterization of bi-layered magnetic nanoparticles synthesized via two-step surface-initiated ring-opening polymerization

2015 ◽  
Vol 87 (11-12) ◽  
pp. 1085-1097 ◽  
Author(s):  
Li Wang ◽  
Stefan Baudis ◽  
Karl Kratz ◽  
Andreas Lendlein
Keyword(s):  
Magnetic Nanoparticles ◽  
Ring Opening ◽  
Average Molecular Weight ◽  
Polymer Networks ◽  
Gel Permeation Chromatography ◽  
Degree Of Crystallinity ◽  
Scanning Calorimetry ◽  
H Nmr ◽  
Transmission Electron

AbstractA versatile strategy to integrate multiple functions in a polymer based material is the formation of polymer networks with defined nanostructures. Here, we present synthesis and comprehensive characterization of covalently surface functionalized magnetic nanoparticles (MNPs) comprising a bi-layer oligomeric shell, using Sn(Oct)2 as catalyst for a two-step functionalization. These hydroxy-terminated precursors for degradable magneto- and thermo-sensitive polymer networks were prepared via two subsequent surface-initiated ring-opening polymerizations (ROPs) with ω-pentadecalactone and ε-caprolactone. A two-step mass loss obtained in thermogravimetric analysis and two distinct melting transitions around 50 and 85°C observed in differential scanning calorimetry experiments, which are attributed to the melting of OPDL and OCL crystallites, confirmed a successful preparation of the modified MNPs. The oligomeric coating of the nanoparticles could be visualized by transmission electron microscopy. The investigation of degrafted oligomeric coatings by gel permeation chromatography and 1H-NMR spectroscopy showed an increase in number average molecular weight as well as the presence of signals related to both of oligo(ω-pentadecalactone) (OPDL) and oligo(ε-caprolactone) (OCL) after the second ROP. A more detailed analysis of the NMR results revealed that only a few ω-pentadecalactone repeating units are present in the degrafted oligomeric bi-layers, whereby a considerable degree of transesterification could be observed when OPDL was polymerized in the 2nd ROP step. These findings are supported by a low degree of crystallinity for OPDL in the degrafted oligomeric bi-layers obtained in wide angle X-ray scattering experiments. Based on these findings it can be concluded that Sn(Oct)2 was suitable as catalyst for the preparation of nanosized bi-layered coated MNP precursors by a two-step ROP.

Characterization of Nanocrystalline γ–Fe2O3Prepared by Wet Chemical Method

1999 ◽  
Vol 14 (4) ◽  
pp. 1570-1575 ◽  
Author(s):  
G. Ennas ◽  
G. Marongiu ◽  
A. Musinu ◽  
A. Falqui ◽  
P. Ballirano ◽  
...  
Keyword(s):  
Isothermal Treatment ◽  
X Ray Diffraction ◽  
Ferrous Chloride ◽  
Scanning Calorimetry ◽  
Direct Transformation ◽  
X Ray ◽  
Transmission Electron ◽  
Xrd Techniques ◽  
Kinetics Of

Homogeneous maghemite (γ–Fe2O3) nanoparticles with an average crystal size around 5 nm were synthesized by successive hydrolysis, oxidation, and dehydration of tetrapyridino-ferrous chloride. Morphological, thermal, and structural properties were investigated by transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and x-ray diffraction (XRD) techniques. Rietveld refinement indicated a cubic cell. The superstructure reflections, related to the ordering of cation lattice vacancies, were not detected in the diffraction pattern. Kinetics of the solid-state phase transition of nanocrystalline maghemite to hematite (α–Fe2O3), investigated by energy dispersive x-ray diffraction (EDXRD), indicates that direct transformation from nanocrystalline maghemite to microcrystalline hematite takes place during isothermal treatment at 385 °C. This temperature is lower than that observed both for microcrystalline maghemite and for nanocrystalline maghemite supported on silica.

Characterization of Poly (Vinyl Alcohol) /Silver Nanocomposites Prepared by Heat Treatment Method

2010 ◽  
Vol 26-28 ◽  
pp. 127-130 ◽  
Author(s):  
Wei Pan ◽  
Hui Li ◽  
Yan Chen
Keyword(s):  
Heat Treatment ◽  
Vinyl Alcohol ◽  
Treatment Method ◽  
Poly Vinyl Alcohol ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Ag Particles ◽  
Nanoparticle Composites ◽  
Heat Treatment Method

Poly (vinyl alcohol) (PVA)/silver (Ag) nanoparticle composites were prepared via heat treatment of a mixture solution of silver nitrate (AgNO3) and PVA. The resultant composites were characterized by infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). XRD results showed that pure phase Ag was obtained in the prepared nanocomposites. They also showed that crystallinity of PVA was largely decreased after the composition with nano-sized Ag. TEM results showed that the Ag particles were in sphere shape with 10-40nm diameter in the as-prepared nanocomposites. DSC results showed that the glass transition temperature of the nanocomposites was enhanced by the incorporation of Ag.

scholarly journals Synthesis and Characterization of Orotic Acid Loaded Chitosan Inclusion Complex

2020 ◽  
Vol 10 (01) ◽  
pp. 1-4
Author(s):  
ABM Helal Uddin ◽  
Abdelkader Hassani ◽  
Abul K. Azad ◽  
Hamid H. Enezei ◽  
Siti A. Hussain
Keyword(s):  
Electron Microscopy ◽  
Inclusion Complex ◽  
Orotic Acid ◽  
Drug Delivery Systems ◽  
Freeze Drying ◽  
Synthesis And Characterization ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transmission Electron

The current study aims to improve drug release properties of orotic acid loaded with chitosan inclusion complex (OA/CS). The OA/CS inclusion complex was synthesized using the freeze-drying technique. The characterization of inclusion OA/CS was carried out using fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), differential scanning calorimetry (DSC), zeta sizer, and transmission electron microscopy (TEM). Furthermore, the size of OA/CS ranged between 58 nm and 200 nm, and the zeta potential was 30 mV. Thus, this study indicates that OA/CS has a promising future to develop a carrier for drug delivery systems further.

scholarly journals Preparation and characterization of baicalein loaded phytosomes: Assessment of in vitro parameters

2020 ◽  
Vol 12 (4) ◽  
pp. 22-29
Author(s):  
KanchanV Zade ◽  
Alok Pal Jain
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Differential Scanning Calorimetry ◽  
Herbal Extracts ◽  
Scanning Calorimetry ◽  
Reverse Phase ◽  
Tem Analysis ◽  
Transmission Electron

Phytosome is a complex between natural active ingredient and a phospholipid. Further, phytosomes been applied to many popular herbal extracts or active molecules for augmenting oral dissolution. Therefore, in present investigation, orally administered Baicalein, atype of flavanoids, is poorly absorbed, and shows suboptimal dissolution. The phytosomes encapsulating baicalein (1:1 Mm) were prepared by reverse phase evaporation method followed by lyophilization. Transmission electron microscopy (TEM) analysis revealed that phytosomes were almost spherical in shape with particle size below 100 nm. The Powder ex-ray diffraction (PXRD) and differential scanning calorimetry (DSC) demonstrated that Baicalein loaded phytosomes were amorphous in nature. Amorphization of therapeutic moiety leads to improvement in dissolution. In conclusion, epigallocatechin loaded phytosomes exhibited promising results and warrant further in vitro andin vivo investigations under a set of stringent parameters for transforming in to a clinically viable products.

scholarly journals Characterization of the Spindle Morphology Nanomicelles Assembled from Sericin and Gelatin

2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Xiaozhou Su ◽  
Lei Li ◽  
Weihan Huang
Keyword(s):  
Electron Microscopy ◽  
Protein Concentration ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Ft Ir ◽  
And Storage ◽  
Ft Ir Spectroscopy

Complex nanomicelles were prepared by sericin and type A gelatin with molecular weight of 5789 Da and 128664 Da separately. The assembling conditions were as follows: mass ratio (sericin/gelatin) was 1 : 1, protein concentration was 0.5%, temperature was 35°C, and assembling time was 18 hours. Scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), and dynamic light scattering (DLS) were conducted to observe and characterize the complex nanomicelles. Results showed that the complex sericin/gelatin micelles was a kind of nanospindle micelles. The micelles had high electrochemical stability, thermal stability, antidilution stability, and storage stability.

Formation and characterization of silica-coated HAP particles

2012 ◽  
Vol 19 (2) ◽  
pp. 107-112
Author(s):  
Hongxin Wang ◽  
Xiaoming Chen ◽  
Dongji Cheng
Keyword(s):  
Colloidal Stability ◽  
Particle Surface ◽  
Silica Coating ◽  
Esterification Reaction ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Infrared Spectral ◽  
Hydrolysis Of

AbstractNanophase hydroxyapatite (HAP) particles were coated with silica via the hydrolysis of tetraethyl orthosilicate after a dodecyl alcohol based esterification reaction. The nanocomposite particles were characterized by transmission electron spectroscopy, scanning electron microscopy, X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, thermogravimetry and differential scanning calorimetry, sedimentation time and zeta potential (ζ) studies. A sequential change in infrared spectral features characteristic of HAP was accompanied by an increase in features characteristic of silica as revealed by FTIR. The silica coating enhanced the colloidal stability of HAP in aqueous suspensions. This behavior can be explained based on a heterocoagulation coating mechanism in which silica clusters adsorb onto the HAP particle surface.

Preparation and characterization of poly(ethylene 2,5-furandicarboxylate/nanocrystalline cellulose composites via solvent casting

2017 ◽  
Vol 37 (9) ◽  
pp. 869-878 ◽  
Author(s):  
Amandine Codou ◽  
Nathanaël Guigo ◽  
Jesper Gabriël van Berkel ◽  
Ed de Jong ◽  
Nicolas Sbirrazzuoli
Keyword(s):  
Electron Microscopy ◽  
Crystallization Temperature ◽  
Nanocrystalline Cellulose ◽  
Solvent Casting ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Cellulose Composites ◽  
Poly Ethylene ◽  
Thermal Stability Of

AbstractThe effect of nanocrystalline cellulose dispersion on the nonisothermal crystallization of poly(ethylene 2,5-furandicarboxylate) (PEF) has been investigated by means of solvent casting. The cellulose dispersion plays a significant role on the crystallization temperature, thus dispersive equipments of increasing energies were employed to improve the cellulose particles disaggregation. Therefore, ultra-sonic bath, ultra-sonication, and ultra-turrax were used to disperse cellulose nanocrystals in 1,1,1,3,3,3-hexafluoro-2-propanol. Dissolved separately in the same solvent, PEF was then poured into the cellulose suspension before casting. The cellulose whiskers were inspected by transmission electron microscopy. Differential scanning calorimetry was used to measure the crystallization temperature, while scanning electron microscopy visualized the cellulose dispersion at the fracture surface. After investigation on the interaction of cellulose/PEF via Fourier transform infrared spectroscopy, the thermal stability of the blends was measured by means of thermogravimetric analysis.

scholarly journals Mineralogical and Geochemical Characterization of Asbestiform Todorokite, Birnessite, and Ranciéite, and Their host Mn-Rich Deposits from Serra D’Aiello (Southern Italy)

Fibers ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 9
Author(s):  
Andrea Bloise ◽  
Domenico Miriello ◽  
Rosanna De Rosa ◽  
Giovanni Vespasiano ◽  
Ilaria Fuoco ◽  
...  
Keyword(s):  
Energy Dispersive Spectrometry ◽  
Southern Italy ◽  
Industrial Applications ◽  
Scanning Calorimetry ◽  
Geochemical Characterization ◽  
X Ray ◽  
Transmission Electron ◽  
Terrestrial Environments ◽  
Strong Control

Manganese ores, especially the oxyhydroxides in their different forms, are the dominant Mn-bearing minerals that occur in marine and terrestrial environments, where they are typically found as poorly crystalline and intermixed phases. Mn oxyhydroxides have a huge range of industrial applications and are able to exert a strong control on the mobility of trace metals. This paper reports the results of a detailed study on the Mn oxyhydroxides occurring in the manganiferous deposit outcropping in the Messinian sediments from Serra D’Aiello (Southern Italy). Nine Mn samples were characterized in detail using X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), thermogravimetry (TG), transmission electron microscopy combined with energy dispersive spectrometry (TEM/EDS), and X-ray fluorescence (XRF). The results indicated that the Mn deposit included the oxyhydroxide mineral species birnessite, todorokite, and rancièite. The size, morphology, and chemical composition of Mn oxyhydroxide samples were investigated in order to define their impact on the environment and human health. Todorokite displayed asbestiform shapes and could disperse fibers of breathable size in the air. Furthermore, since in-depth characterization of minerals within Mn deposits may be the first step toward understanding the genetic processes of manganese deposits, hypotheses about the genesis of the Mn oxyhydroxide deposits were discussed.

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