The study of atmospherically deposited Spheroidal Carbonaceous Particles (SCP) from the Kongsfjorden, Svalbard

2017 ◽  
Vol 7 (2) ◽  
pp. 206-215
Author(s):  
Neelu Singh ◽  
Vartika Singh ◽  
Chikkamadaiah Krishnaiah
Keyword(s):  
Fossil Fuels ◽  
Size Range ◽  
Spheroidal Carbonaceous Particles ◽  
Carbonaceous Particles ◽  
X Ray ◽  
Remote Areas ◽  
Inland Lakes ◽  
Large Particles ◽  
Source Of Pollution

The surface sediment samples of Kongsfjorden were analyzed for the Spheroidal Carbonaceous Particles (SCP) in an attempt to document the SCP in the environment other than previously studied inland lakes and snow and also to understand the probable source of industrial atmospheric pollution. The SCP are derived from the combustion of fossil fuels at high temperatures and are not produced naturally. They are chemically inert in both sediment and water and thus provide the indestructible record of atmospherically deposited pollutants in remote areas and anthropogenic impact on pristine environments. The SCP were recovered from different locations of the fjord and were classified according to their size range (small particles, 5-10 µm – large particles, 20-50 µm). The characterization of the spherical carbonaceous particles (shape, size, morphology, color etc.) was done under the light microscope. The detailed morphological features and chemical composition of SCP were studied using Scanning Electron Microscope equipped with Energy Dispersive X-Ray (SEM-EDX). The result shows that in term of a source of pollution in the area, long-range transportation is the major source of pollution but local sources cannot be ignored. This is a first attempt to study the SCP from the Kongsfjorden.

Synthesis and Characterization of Superparamagnetic NiFe2O4 Nanoparticles

2010 ◽  
Vol 663-665 ◽  
pp. 1325-1328 ◽  
Author(s):  
De Hui Sun ◽  
De Xin Sun ◽  
Yu Hao
Keyword(s):  
Room Temperature ◽  
Size Range ◽  
X Ray Diffraction ◽  
Inverse Spinel ◽  
Cubic Crystal ◽  
Xrd Pattern ◽  
X Ray ◽  
Nife2o4 Nanoparticles ◽  
Average Size

The superparamagnetic NiFe2O4 nanoparticles were synthesized using a hydrothermal technology through P123 sphere micelles as ‘nanoreactor’ in this work. Their morphologies, structures, surface properties and magnetism were characterized by FE-SEM, XRD, FTIR, and VSM, respectively. The nickel ferrite samples are nearly spherical and homogeneous nanoparticles with average size range of about 50-120 nm. They possess superparamagnetism at room temperature and higher saturation magnetization. X-ray diffraction (XRD) pattern confirms that the samples belong to the cubic crystal system with an inverse-spinel structure. Fourier transform infrared (FTIR) absorption spectrum indicates that the NiFe2O4 nanoparticles are stabilized by the P123 adsorbed on the surface of nanoparticles.

Characterization of Nanostructured Nickel Aluminate Formation during Mechano-Chemical Recycling of Spent NiO/Al2O3 Catalyst

2011 ◽  
Vol 364 ◽  
pp. 186-190
Author(s):  
Karim Nazemi Mohammad ◽  
Saeed Sheibani ◽  
Fereshteh Rashchi ◽  
Victor Gonzalez De La Cruz ◽  
Alfonso Caballero Martínez
Keyword(s):  
Electron Microscopy ◽  
Size Range ◽  
Spherical Shape ◽  
Research Use ◽  
Chemical Recycling ◽  
X Ray Diffraction ◽  
Nickel Aluminate ◽  
X Ray ◽  
Transmission Electron

In this research, use of mechanical alloying method, as a new and effective route for the recycling of spent NiO/Al2O3catalyst to nanostructured nickel aluminate spinel was investigated. Samples were characterized using different techniques such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). It was found that the formation of NiAl2O4was started between 15 to 20 hours of milling and completed after 60 hours. The final particles had relatively spherical shape with the size range of 5-50 nm.

Synthesis and Characterization of CoFe2O4 Nanoparticles

2011 ◽  
Vol 261-263 ◽  
pp. 533-536 ◽  
Author(s):  
Zhen Feng Cui ◽  
Dehui Sun
Keyword(s):  
Solution Method ◽  
Size Range ◽  
Information Storage ◽  
Resonance Imaging ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Rhombohedral Crystal ◽  
Average Size

We synthesized the magnetic CoFe2O4nanoparticles using a solution method in the presence of hexamethylenetetramine (HMTA) at 85 °C for 6 h. Their morphologies, structures, surface properties and magnetism were characterized by Field emission scanning electron microscopy (FE-SEM) images, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and Vibrating sample magnetometer (VSM), respectively. FE-SEM results show that the synthesized samples are irregular nanoparticles with average size range of about 40-120 nm. XRD confirms that the samples belong to the rhombohedral crystal system. The magnetic CoFe2O4nanoparticles have the potential application in magnetic resonance imaging, high-density information storage and drug delivery.

Synthesis and Characterization of Quaternary Ti-Si-C-N Film Deposited by Middle Frequency Magnetron Sputtering

2012 ◽  
Vol 581-582 ◽  
pp. 540-543
Author(s):  
Jin Long Jiang ◽  
Di Chen ◽  
Wei Jun Zhu
Keyword(s):  
Magnetron Sputtering ◽  
Elastic Recovery ◽  
Amorphous Structure ◽  
Columnar Structure ◽  
Maximum Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Large Particles ◽  
Si Wafer

Quaternary Ti-Si-C-N films were deposited Si wafer by middle frequency magnetron sputtering Ti80Si20 twin-targets in mixture atmosphere of Ar, CH4 and N2. Scanning electron microscopy (SEM) and x-ray diffraction (XRD) results indicate that the films present an amorphous structure with no columnar structure. These films are quite uniform and dense without large particles. The film deposited at 10 sccm CH4 and 10 sccm N2 flow rates exhibits a maximum hardness of 18.9 GPa and high elastic recovery of 97%.

scholarly journals Chemical characterization of PM10 in two small towns located in South Poland

Nukleonika ◽  
2021 ◽  
Vol 66 (1) ◽  
pp. 29-34
Author(s):  
Anna Turek-Fijak ◽  
Joanna Brania ◽  
Katarzyna Styszko ◽  
Damian Zięba ◽  
Zdzisław Stęgowski ◽  
...  
Keyword(s):  
Fossil Fuels ◽  
Chemical Elements ◽  
Chemical Characterization ◽  
Small Towns ◽  
Ray Method ◽  
Air Samples ◽  
X Ray ◽  
Limit Value ◽  
High Concentrations

Abstract The purpose of this study is to analyse the elements and PM10 concentrations in air samples gathered in the winter of 2017/2018 in two small towns, namely Skala and Wadowice. The chemical elements were identified for each sample using the energy dispersive X-ray method. The spectrometer was equipped, among others, with an Mo-X-ray tube which was the source of the photons and the Si(Li) detector. The following chemical elements: Cl, K, Fe, Ca, Zn, Pb, Br, Ti, Cu, Mn, V, Co, Rb, Ni, Sr, and Cr were identified in the samples. In addition, As and Se were identified in Wadowice. First, the results were compared with each other and then with the results for the nearest city. It was observed that the PM10 concentrations were significantly higher than the UE limit value for PM10, which equals 50 μg·m−3 per 24 h. Moreover, the high concentrations of, among others, K, Pb, Cl or Zn, are likely to be linked with fossil fuels combustion and biomass burning. The levels of element concentrations in Wadowice and Skala resemble the levels observed several years earlier in Krakow.

scholarly journals Growth and Characterization of Polycrystalline Silicon Thin Films for Photocatalytic Splitting of Water in Oxide-Si Tandem Cells

2020 ◽  
Author(s):  
Ali Zahid ◽  
Umer Zahid ◽  
Aamir Hasan ◽  
Muhammad Khuldoon
Keyword(s):  
Band Gap ◽  
Fossil Fuels ◽  
Crystalline Silicon ◽  
X Ray Diffraction ◽  
Active Electrode ◽  
Band Gap Engineering ◽  
X Ray ◽  
Silicon Thin Films ◽  
Deposition Parameters

With the decline in fossil fuels, hydrogen-based alternatives provide a reliable and clean source for sustainable energy generation. In these endeavors, photochemical splitting for hydrogen production through tandem cells has been the source of much theoretical and experimental research in science. Much focus has been placed on interfacial band gap engineering as one of the most promising routes in the generation of hydrogen.This present work explores sputtering of n-silicon to form the active electrode in a n-Si | n-TiO2 tandem cell and investigates the effect of variations in sputtering and post sputtering treatment parameters (rapid thermal annealing and long cycle annealing) for successful deposition of crystalline Silicon. The samples were successfully characterized via Raman Spectroscopy, X-ray Diffraction and Optical Transmission Spectroscopy to ascertain prevalent crystalline order and optical band gap, under different sputtering and post-sputtering conditions. Relevant conclusions were drawn to ascertain the best possible deposition parameters of n-Si for photocatalytic water splitting.

Preparation and Characterization of Carbon Nanospheres Using Sugar as a Precursor

2019 ◽  
Vol 796 ◽  
pp. 11-16
Author(s):  
Suriani Ibrahim ◽  
Lee Qi ◽  
Shaifulazuar Rozali ◽  
Nik Nazri Nik Ghazali ◽  
Tuan Zahari Tuan Zaharinie ◽  
...  
Keyword(s):  
Lithium Batteries ◽  
Renewable Resources ◽  
Fossil Fuels ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Chemical Reduction Method ◽  
Carbon Nanospheres ◽  
X Ray ◽  
Renewable Natural Resources

A carbon nanosphere has been used in various applications such as supercapacitors, lithium batteries, fuel cells and catalyst carriers due to their outstanding properties. The precursors commonly used to synthesize carbon nanospheres are methane, polymer and alginate solution. These precursors come from fossil fuels which are non-renewable resources where future access is limited. Hence, alternatives of renewable natural resources to develop carbon-based precursors should be studied. The aim of this work is to study properties of carbon nanospheres synthesized from sugar by using chemical reduction method. The surface morphology of mesoporous carbon nanospheres were observed by field emission scanning electron microscopy (FESEM) and the expected elemental composition by energy dispersive X-ray (EDX) analysis. The FESEM images showed carbon nanospheres having irregular spherical nanostructures with a range of diameter from 84.04 – 834.86 nm. The formation of carbon nanospheres with highly carbon content can be observed from EDX spectrum.

scholarly journals Comparison of Spheroidal Carbonaceous Particle Data with Modelled Atmospheric Black Carbon Concentration and Deposition and Air Mass Sources in Northern Europe, 1850–2010

2013 ◽  
Vol 2013 ◽  
pp. 1-15 ◽  
Author(s):  
Meri Ruppel ◽  
Marianne T. Lund ◽  
Henrik Grythe ◽  
Neil L. Rose ◽  
Jan Weckström ◽  
...  
Keyword(s):  
Black Carbon ◽  
Fossil Fuels ◽  
Transport Model ◽  
Northern Europe ◽  
Spheroidal Carbonaceous Particles ◽  
Carbonaceous Particle ◽  
Carbonaceous Particles ◽  
Air Mass ◽  
Back Trajectories ◽  
Transport Patterns

Spheroidal carbonaceous particles (SCP) are a well-defined fraction of black carbon (BC), produced only by the incomplete combustion of fossil fuels such as coal and oil. Their past concentrations have been studied using environmental archives, but, additionally, historical trends of BC concentration and deposition can be estimated by modelling. These models are based on BC emission inventories, but actual measurements of BC concentration and deposition play an essential role in their evaluation and validation. We use the chemistry transport model OsloCTM2 to model historical time series of BC concentration and deposition from energy and industrial sources and compare these to sedimentary measurements of SCPs obtained from lake sediments in Northern Europe from 1850 to 2010. To determine the origin of SCPs we generated back trajectories of air masses to the study sites. Generally, trends of SCP deposition and modelled results agree reasonably well, showing rapidly increasing values from 1950, to a peak in 1980, and a decrease towards the present. Empirical SCP data show differences in deposition magnitude between the sites that are not captured by the model but which may be explained by different air mass transport patterns. The results highlight the need for numerous observational records to reliably validate model results.

scholarly journals Development of powder diffraction apparatus for small-angle X-ray scattering measurements

2013 ◽  
Vol 46 (2) ◽  
pp. 573-576 ◽  
Author(s):  
Attila Bóta
Keyword(s):  
Powder Diffraction ◽  
Size Range ◽  
Wide Angle ◽  
X Ray ◽  
X Ray Scattering ◽  
Collimation System ◽  
Scattering Measurements ◽  
Wide Size Range ◽  
Ray Scattering

A novel type of X-ray collimation system attached to commercial powder diffractometers makes the structural characterization of nanomaterials possible in a wide size range from <0.1 to 100 nm by combination of the small- and wide-angle X-ray scattering techniques. There is no dead interval in the detection between the small- and wide-angle regimes. This device can be attached to any existing `θ/θ' powder diffractometer, providing a multi-functional small- and wide-angle X-ray scattering/diffraction (SWAXS) apparatus. After proper alignment and adjustment, the device can be removed and re-attached at any time to switch between normal and SWAXS functions.

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