Synthesis and characterization of mesoporous carbon spheres

AbstractA three-step method was used for the synthesis of mesoporous carbon sphere (MCS) material: firstly, silica (SiO2) nanoparticles were synthesized by the modified Stöber procedure; secondly, tetraethyl orthosilicate (TEOS) and cetyltrimethylammonium chloride (CTAC) were grafted onto SiO2 core nanoparticles to prepare SiO2@SiO2-CTAC hard templates; lastly, MCS material was fabricated by carbonizing and selective leaching SiO2/resorcinol-formaldehyde (RF) composites. The influence of the mass ratio of R-F/silica on the structure, morphology and crystal form was studied. The results indicate that the MCS materials have a uniform morphology. The increase of the mass ratio of R-F/silica can increase the specific surface area and pore volume. The three-step method provides a cost-effective procedure for the fabrication of MCS materials with uniform morphology.

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Preparation and Characterization of Mesoporous Carbon Materials Based on Hard Coal-Tar Pitch

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.1363 ◽

2013 ◽

Vol 750-752 ◽

pp. 1363-1368 ◽

Cited By ~ 1

Author(s):

Gui Ying Xu ◽

Jin Feng Bai ◽

Jian Zhang ◽

Li Hua Zhang ◽

Rui Ni ◽

...

Keyword(s):

Carbon Source ◽

Specific Surface ◽

Mesoporous Carbon ◽

Coal Tar ◽

Hard Coal ◽

Coal Pitch ◽

Vitamin B ◽

Mesoporous Carbons ◽

Mass Ratio ◽

Step Method

Mesoporous carbons were prepared by one step method using hard coal pitch as carbon source, in which magnesium oxide was adopted as template. The adsorption value of vitamin B12, specific surface and pore size distribution, surface topography of mesoporous carbons were tested by spectrophotometer, specific surface analyzer and scanning electron microscopy. The results showed that the vitamin B12 absorption value on mesoporous carbon could be improved with suitable carbonization temperature and mass ratio of template agent to carbon source. The maximum value achieved to 103.82mg/g when the mass ratio of MgO to modified pitch was 8:2.

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A Possible Basis for Nondestructive Characterization of Ropes of Nylon 6

MRS Proceedings ◽

10.1557/proc-503-243 ◽

1997 ◽

Vol 503 ◽

Author(s):

H. Jiang ◽

M. K. Davis ◽

R. K. Eby ◽

P. Arsenovic

Keyword(s):

Tensile Strength ◽

Service Life ◽

Fiber Diameter ◽

Structural Parameters ◽

Crystal Form ◽

Nylon 6 ◽

Remaining Service Life ◽

Nondestructive Characterization ◽

Fractional Content

ABSTRACTPhysical properties and structural parameters have been measured for ropes of nylon 6 as a function of the number of use operations. The fractional content of the α crystal form, sound velocity, birefringence, tensile strength and length all increase systematically and significantly with increasing the number of use operations. The fractional content of the γ crystal form and fiber diameter decrease with use. These trends indicate that the measurement of such properties and structural parameters, especially the length, provide a possible basis for establishing a reliable, rapid, and convenient nondestructive characterization method to predict the remaining service life of nylon 6 ropes.

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Monitoring of Petroleum-Related Environmental Contamination Using Fluorescence Fingerprinting

Water Practice & Technology ◽

10.2166/wpt.2006.029 ◽

2006 ◽

Vol 1 (2) ◽

Cited By ~ 1

Author(s):

P. Literathy ◽

M. Quinn

Keyword(s):

Environmental Contamination ◽

Statistical Evaluation ◽

Oil Pollution ◽

Emission Spectra ◽

Cost Effective ◽

Petroleum Products ◽

Danube River ◽

Aromatic Components ◽

Analytical Approaches

Petroleum and its refined products are considered the most complex contaminants frequently impacting the environment in significant quantities. They have heterogeneous chemical composition and alterations occur during environmental weathering. No single analytical method exists to characterize the petroleum-related environmental contamination. For monitoring, the analytical approaches include gravimetric, spectrometric and chromatographic methods having significant differences in their selectivity, sensitivity and cost-effectiveness. Recording fluorescence fingerprints of the cyclohexane extracts of the water, suspended solids, sediment or soil samples and applying appropriate statistical evaluation (e.g. by correlating the concatenated emission spectra of the fingerprints of the samples with arbitrary standards (e.g. petroleum products)), provides a powerful, cost-effective analytical tool for characterization of the type of oil pollution and detecting the most harmful aromatic components of the petroleum contaminated matrix. For monitoring purposes, the level of the contamination can be expressed as the equivalent concentration of an appropriate characteristic standard, based on the fluorescence intensities at the relevant characteristic wavelengths. These procedures are demonstrated in the monitoring of petroleum-related pollution in the water and suspended sediment in the Danube river basin

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Green Synthesis and Spectroscopic Studies of Ag-rGO Nanocomposites for Highly Selective Mercury (II) Sensing

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681207666170705143629 ◽

2018 ◽

Vol 9 (1) ◽

pp. 101-108 ◽

Cited By ~ 1

Author(s):

Shubhangi J. Mane-Gavade ◽

Sandip R. Sabale ◽

Xiao-Ying Yu ◽

Gurunath H. Nikam ◽

Bhaskar V. Tamhankar

Keyword(s):

Green Synthesis ◽

Color Change ◽

Limit Of Detection ◽

Aqueous Media ◽

Suitable Condition ◽

Cost Effective ◽

Spectroscopic Studies ◽

Calibration Plot ◽

First Time

Introduction: Herein we report the green synthesis and characterization of silverreduced graphene oxide nanocomposites (Ag-rGO) using Acacia nilotica gum for the first time. Experimental: We demonstrate the Hg2+ ions sensing ability of the Ag-rGO nanocomposites form aqueous medium. The developed colorimetric sensor method is simple, fast and selective for the detection of Hg2+ ions in aqueous media in presence of other associated ions. A significant color change was noticed with naked eye upon Hg2+ addition. The color change was not observed for cations including Sr2+, Ni2+, Cd2+, Pb2+, Mg2+, Ca2+, Fe2+, Ba2+ and Mn2+indicating that only Hg2+ shows a strong interaction with Ag-rGO nanocomposites. Under the most suitable condition, the calibration plot (A0-A) against concentration of Hg2+ was linear in the range of 0.1-1.0 ppm with a correlation coefficient (R2) value 0.9998. Results & Conclusion The concentration of Hg2+ was quantitatively determined with the Limit of Detection (LOD) of 0.85 ppm. Also, this method shows excellent selectivity towards Hg2+ over nine other cations tested. Moreover, the method offers a new cost effective, rapid and simple approach for the detection of Hg2+ in water samples.

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Semi-automated regional classification of the style of activity of slow rock-slope deformations using PS InSAR and SqueeSAR velocity data

Landslides ◽

10.1007/s10346-021-01654-0 ◽

2021 ◽

Author(s):

Chiara Crippa ◽

Elena Valbuzzi ◽

Paolo Frattini ◽

Giovanni B. Crosta ◽

Margherita C. Spreafico ◽

...

Keyword(s):

Rock Slope ◽

Progressive Failure ◽

Principal Component ◽

Cost Effective ◽

Displacement Rate ◽

Machine Learning Classification ◽

Management Perspective ◽

Alpine Environments

AbstractLarge slow rock-slope deformations, including deep-seated gravitational slope deformations and large landslides, are widespread in alpine environments. They develop over thousands of years by progressive failure, resulting in slow movements that impact infrastructures and can eventually evolve into catastrophic rockslides. A robust characterization of their style of activity is thus required in a risk management perspective. We combine an original inventory of slow rock-slope deformations with different PS-InSAR and SqueeSAR datasets to develop a novel, semi-automated approach to characterize and classify 208 slow rock-slope deformations in Lombardia (Italian Central Alps) based on their displacement rate, kinematics, heterogeneity and morphometric expression. Through a peak analysis of displacement rate distributions, we characterize the segmentation of mapped landslides and highlight the occurrence of nested sectors with differential activity and displacement rates. Combining 2D decomposition of InSAR velocity vectors and machine learning classification, we develop an automatic approach to characterize the kinematics of each landslide. Then, we sequentially combine principal component and K-medoids cluster analyses to identify groups of slow rock-slope deformations with consistent styles of activity. Our methodology is readily applicable to different landslide datasets and provides an objective and cost-effective support to land planning and the prioritization of local-scale studies aimed at granting safety and infrastructure integrity.

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Variable Temperature Synthesis of Tunable Flame-Generated Carbon Nanoparticles

C – Journal of Carbon Research ◽

10.3390/c7020044 ◽

2021 ◽

Vol 7 (2) ◽

pp. 44

Author(s):

Francesca Picca ◽

Angela Di Pietro ◽

Mario Commodo ◽

Patrizia Minutolo ◽

Andrea D’Anna

Keyword(s):

Carbon Nanoparticles ◽

Variable Temperature ◽

Flame Temperature ◽

Cost Effective ◽

Synthesis Process ◽

Electrical Mobility ◽

Material Synthesis ◽

Online Measurements ◽

Degree Of Graphitization

In this study, flame-formed carbon nanoparticles of different nanostructures have been produced by changing the flame temperature. Raman spectroscopy has been used for the characterization of the carbon nanoparticles, while the particle size has been obtained by online measurements made by electrical mobility analysis. The results show that, in agreement with recent literature data, a large variety of carbon nanoparticles, with a different degree of graphitization, can be produced by changing the flame temperature. This methodology allows for the synthesis of very small carbon nanoparticles with a size of about 3-4 nm and with different graphitic orders. Under the perspective of the material synthesis process, the variable-temperature flame-synthesis of carbon nanoparticles appears as an attractive procedure for a cost-effective and easily scalable production of highly tunable carbon nanoparticles.

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Graphene, an Interesting Nanocarbon Allotrope for Biosensing Applications: Advances, Insights, and Prospects

Biomedical Engineering and Computational Biology ◽

10.1177/1179597220983821 ◽

2021 ◽

Vol 12 ◽

pp. 117959722098382

Author(s):

Farid Menaa ◽

Yazdian Fatemeh ◽

Sandeep K Vashist ◽

Haroon Iqbal ◽

Olga N Sharts ◽

...

Keyword(s):

Cost Effective ◽

Genetic Alterations ◽

Multiplex Detection ◽

Quantitative Characterization ◽

Disease Biomarkers ◽

Qualitative And Quantitative ◽

Sensing Systems ◽

Doped Graphene ◽

Bioanalytical Applications

Graphene, a relatively new two-dimensional (2D) nanomaterial, possesses unique structure (e.g. lighter, harder, and more flexible than steel) and tunable physicochemical (e.g. electronical, optical) properties with potentially wide eco-friendly and cost-effective usage in biosensing. Furthermore, graphene-related nanomaterials (e.g. graphene oxide, doped graphene, carbon nanotubes) have inculcated tremendous interest among scientists and industrials for the development of innovative biosensing platforms, such as arrays, sequencers and other nanooptical/biophotonic sensing systems (e.g. FET, FRET, CRET, GERS). Indeed, combinatorial functionalization approaches are constantly improving the overall properties of graphene, such as its sensitivity, stability, specificity, selectivity, and response for potential bioanalytical applications. These include real-time multiplex detection, tracking, qualitative, and quantitative characterization of molecules (i.e. analytes [H2O2, urea, nitrite, ATP or NADH]; ions [Hg2+, Pb2+, or Cu2+]; biomolecules (DNA, iRNA, peptides, proteins, vitamins or glucose; disease biomarkers such as genetic alterations in BRCA1, p53) and cells (cancer cells, stem cells, bacteria, or viruses). However, there is still a paucity of comparative reports that critically evaluate the relative toxicity of carbon nanoallotropes in humans. This manuscript comprehensively reviews the biosensing applications of graphene and its derivatives (i.e. GO and rGO). Prospects and challenges are also introduced.

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Experimental Characterization of Phase Change Materials for Refrigeration Processes

Energies ◽

10.3390/en14113033 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3033

Author(s):

Anastasia Stamatiou ◽

Lukas Müller ◽

Roger Zimmermann ◽

Jamie Hillis ◽

David Oliver ◽

...

Keyword(s):

Energy Density ◽

Phase Change ◽

Thermophysical Properties ◽

Phase Change Materials ◽

Cost Effective ◽

Latent Heat Storage ◽

Lower Energy Density ◽

Change Material ◽

Storage Units

Latent heat storage units for refrigeration processes are promising as alternatives to water/glycol-based storage due to their significantly higher energy densities, which would lead to more compact and potentially more cost-effective storages. In this study, important thermophysical properties of five phase change material (PCM) candidates are determined in the temperature range between −22 and −35 °C and their compatibility with relevant metals and polymers is investigated. The goal is to complement existing scattered information in literature and to apply a consistent testing methodology to all PCMs, to enable a more reliable comparison between them. More specifically, the enthalpy of fusion, melting point, density, compatibility with aluminum, copper, polyethylene (PE), polypropylene (PP), neoprene and butyl rubber, are experimentally determined for 1-heptanol, n-decane, propionic acid, NaCl/water mixtures, and Al(NO3)3/water mixtures. The results of the investigations reveal individual strengths and weaknesses of the five candidates. Further, 23.3 wt.% NaCl in water stands out for its very high volumetric energy density and n-decane follows with a lower energy density but better compatibility with surrounding materials and supercooling performance. The importance of using consistent methodologies to determine thermophysical properties when the goal is to compare PCM performance is highlighted.

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Biodiesel Production from Melia azedarach and Ricinus communis Oil by Transesterification Process

Catalysts ◽

10.3390/catal10040427 ◽

2020 ◽

Vol 10 (4) ◽

pp. 427 ◽

Cited By ~ 3

Author(s):

Muhammad Awais ◽

Sa’ed A Musmar ◽

Faryal Kabir ◽

Iram Batool ◽

Muhammad Asif Rasheed ◽

...

Keyword(s):

Ricinus Communis ◽

Cost Effective ◽

Biodiesel Production ◽

Molar Ratio ◽

Melia Azedarach ◽

Renewable Fuel ◽

Animal Fats ◽

Edible Crops ◽

American Society

Biodiesel is a renewable fuel usually produced from vegetable oils and animal fats. This study investigates the extraction of oil and its conversion into biodiesel by base-catalyzed transesterification. Firstly, the effect of various solvents (methanol, n-hexane, chloroform, di-ethyl ether) on extraction of oil from non-edible crops, such as R. communis and M. azedarach, were examined. It was observed that a higher concentration of oil was obtained from R. communis (43.6%) as compared to M. azedarach (35.6%) by using methanol and n-hexane, respectively. The extracted oils were subjected to NaOH (1%) catalyzed transesterification by analyzing the effect of oil/methanol molar ratio (1:4, 1:6, 1:8 and 1:10) and varying temperature (20, 40, 60 and 80 °C) for 2.5 h of reaction time. M. azedarach yielded 88% and R. communis yielded 93% biodiesel in 1:6 and 1:8 molar concentrations at ambient temperature whereas, 60 °C was selected as an optimum temperature, giving 90% (M. azedarach) and 94% (R. communis) biodiesel. The extracted oil and biodiesel were characterized for various parameters and most of the properties fulfilled the American Society for Testing and Materials (ASTM) standard biodiesel. The further characterization of fatty acids was done by Gas Chromatography/Mass Spectrometer (GC/MS) and oleic acid was found to be dominant in M. azedarach (61.5%) and R. communis contained ricinoleic acid (75.53%). Furthermore, the functional groups were analyzed by Fourier Transform Infrared Spectroscopy. The results suggested that both of the oils are easily available and can be used for commercial biodiesel production at a cost-effective scale.

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