Radioisotope Methods of Analysis and Characterization of Elastomers

1969 ◽  
Vol 42 (1) ◽  
pp. 1-29 ◽  
Author(s):  
D. R. Campbell ◽  
W. C. Warner
Keyword(s):  
Activation Analysis ◽  
Process Control ◽  
Functional Groups ◽  
Beta Emitters ◽  
Recent Advances ◽  
Methods Of Analysis ◽  
Beta Sources ◽  
Made In

Abstract Radioactivity applied to rubber technology encompasses such diverse areas as the effect of radiation on elastomers, use of strong gamma and beta sources for process control, and isotope methods to measure tire tread wear. These applications of radioisotopes have received considerable attention in recent years and the principles and techniques have been discussed extensively in both reviews and original papers. Significant contributions, however, have also been made in advancing elastomer technology through analytical use of radioisotopes of carbon, hydrogen, sulfur, and other beta-emitters, as well as by special radioisotope techniques. This survey discusses recent advances achieved with beta-emitters in vulcanization, diffusion, dispersion, adsorption, coagulation, and determination of functional groups in polymers. In addition, the value of activation analysis and other radioisotope investigative methods for characterization of elastomers is shown.

STUDY PORE CHARACTERIZATION OF γ-ALUMINA – ACTIVATED CARBON COMPOSITE MADE OF CASSAVA PEELS (Manihot esculenta Cranz)

2015 ◽  
Vol 11 (1) ◽  
pp. 47
Author(s):  
Hartini Hartini ◽  
Yuniawan Hidayat ◽  
Mudjijono Mudjijono
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
Total Pore Volume ◽  
Carbon Composite ◽  
Bet Method ◽  
Industrial Standards ◽  
Cassava Peels ◽  
Made In

<p>A composite of γ-alumina and activated carbon made of cassava peels was studied in terms of its pore structures and its properties. The objective of this study was to determine the interaction and structure, as well as the character and pore size of γ-alumina – activated carbon composite.</p><p>Carbon made of cassava peels was activated by H<sub>2</sub>SO<sub>4</sub> and its activities were tested according to the Indonesian Industrial Standards (SII). The addition of activated carbon into γ-alumina made in variations of 10, 20, 30, 40 and 50 % w/w, of the total weight of 10 grams. The composite of γ-alumina - activated carbon was characterized by FTIR, SAA (Surface Area Analyzer), XRD, and determination of Hysteresis Loop composites.</p>The greater addition of activated carbon to γ-alumina causes intermolecular interactions between –O-H groups form rehydrated hydrogen bonds in the composite is greater. The structure of γ-alumina in the composites remain intact although the percentage of activated carbon in composite is large. The total pore volume and surface area using the BET method of the composite decreases with increasing activated carbon percentage. The greater addition of activated carbon to γ-alumina causes size of mesoporous composites decreased with the characteristic of a composite formed is closer to the activated carbon.

Study on Surface Tension and Displacement Efficiency of Ionic Liquid Surfactants Containing Amine Functional Groups

2014 ◽  
Vol 484-485 ◽  
pp. 66-69
Author(s):  
Xiu Li Zhao ◽  
Chang Bao Zhang ◽  
Cheng Chen ◽  
Guo Qiao Li ◽  
Da Liu
Keyword(s):  
Surface Tension ◽  
Ionic Liquid ◽  
Functional Groups ◽  
Water Flooding ◽  
Displacement Efficiency ◽  
Oil Displacement ◽  
Wave Numbers ◽  
Infrared Spectrometer

Description is given to preparation of three ionic liquid surfactants containing amine functional groups, characterization of their functional groups using the infrared spectrometer, determination of their surface tension and the oil displacement test in this paper to investigate the effect of alkane branch chains with different carbon numbers on the surface tension and the displacement efficiency. The result shows that, the surfactants exhibit the structural characteristic of the ionic liquid as the characteristic absorption peaks occur on C-N and C-H of the imidazole rings at the wave numbers of 1338cm-1, 1234cm-1, 1465cm-1 and 3142cm-1, respectively. The surface tension isothermal curves and the oil displacement test proved that the ionic liquid imidazole surfactants with shorter-chain groups are more active on surface, with the minimal surface tension up to 32.5 mN/m, and led to higher displacement efficiency, increasing by 3.3% at the concentration of 1000mg/L compared with the water flooding.

scholarly journals STUDY PORE CHARACTERIZATION OF γ-ALUMINA – ACTIVATED CARBON COMPOSITE MADE OF CASSAVA PEELS (Manihot esculenta Cranz)

2016 ◽  
Vol 11 (1) ◽  
pp. 47
Author(s):  
Hartini Hartini ◽  
Yuniawan Hidayat ◽  
Mudjijono Mudjijono
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
Total Pore Volume ◽  
Carbon Composite ◽  
Bet Method ◽  
Industrial Standards ◽  
Cassava Peels ◽  
Made In

<p>A composite of γ-alumina and activated carbon made of cassava peels was studied in terms of its pore structures and its properties. The objective of this study was to determine the interaction and structure, as well as the character and pore size of γ-alumina – activated carbon composite.</p><p>Carbon made of cassava peels was activated by H<sub>2</sub>SO<sub>4</sub> and its activities were tested according to the Indonesian Industrial Standards (SII). The addition of activated carbon into γ-alumina made in variations of 10, 20, 30, 40 and 50 % w/w, of the total weight of 10 grams. The composite of γ-alumina - activated carbon was characterized by FTIR, SAA (Surface Area Analyzer), XRD, and determination of Hysteresis Loop composites.</p>The greater addition of activated carbon to γ-alumina causes intermolecular interactions between –O-H groups form rehydrated hydrogen bonds in the composite is greater. The structure of γ-alumina in the composites remain intact although the percentage of activated carbon in composite is large. The total pore volume and surface area using the BET method of the composite decreases with increasing activated carbon percentage. The greater addition of activated carbon to γ-alumina causes size of mesoporous composites decreased with the characteristic of a composite formed is closer to the activated carbon.

scholarly journals An absolute determination of the acceleration due to gravity

1939 ◽  
Vol 238 (787) ◽  
pp. 65-123 ◽  
Keyword(s):  
Electric Current ◽  
Absolute Value ◽  
Absolute Determination ◽  
Accurate Knowledge ◽  
Recent Advances ◽  
Gravity Measurements ◽  
Relative Gravity ◽  
The Absolute ◽  
Made In

Recent advances in the precision obtainable in length and time measurements have made it possible to determine the absolute value of the acceleration due to gravity with greater accuracy than has hitherto been possible. An accurate knowledge of the actual value of the acceleration due to gravity is essential, for example, in connexion with the determination of the absolute unit of electric current by means of the current balance. It has been usual to refer relative gravity measurements made in this country to the absolute value determined at Potsdam by Kühnen and Furtwängler (1906) over 30 years ago, and although relative determinations can now be carried out with an accuracy approaching one part in a million, it appears that the basic Potsdam value may be in error by something between one and two parts in 100,000. Very few absolute determinations have been made within the last 50 years, but those which have been carried out at various stations show discrepancies of this order when related to the Potsdam value by relative determinations.

scholarly journals HUMIC ACID CRACKING BY ACTIVATED CLAY CATALYSTS AND IDENTIFICATION OF ITS PRODUCTS

2015 ◽  
Vol 1 (1) ◽  
pp. 9-17
Author(s):  
Abdullah Abdullah ◽  
Rina Twinasty ◽  
Taufiqur Rohman
Keyword(s):  
Humic Acid ◽  
Surface Area ◽  
Functional Groups ◽  
Humic Acids ◽  
Pore Radius ◽  
Ash Content ◽  
Fixed Bed Reactor ◽  
Liquid Smoke

Humic acid is a compound of colloidal,amorphous, and complex aromatic polymerwith functional groups of -COOH (carboxyl), -OH (phenol), and C = O (carbonyl). The presence of these functional groups provides a rationale for assuming that humic acids have a potential to produce phenolic, carboxylic and carbonylic compounds through cracking process. In this study the cracking was done by isolating humic acids from peat soil, and facilitated by a clay catalyst which had been activated. Humic acids were isolated by extracting the acids from the peat with NaOH and HCl. The characterization of humic acids included the determination of the ash content by gravimetric method and the analysis of the functional groups of humic acids by Infrared spectrometer (FTIR). The clay to be activated was shaped into two forms, pellets and 20-40 mesh granules. The clay was activated by immersing it in HCl and NH4NO3, and then calcined. The characterization of catalysts included the determination of acidity and the Si/Al ratio gravimetrically, as well as the analysis of the pore volume, maximum pore radius, surface area and average pore radius by Surface Area Analyzer NOVA-1000. Humic acid cracking was performed by a fixed-bed reactor system at a temperature of 400°C. The Liquid smoke, the product of cracking, was analyzed by GC and GC-MS to determine the number of compounds and major compounds contained in the liquid smoke. The results show that the isolated humic acid had ash content of 9.10%. Activated clay had acidity and Si/Al ratio higher than the clay before actifated. Based on the analyses of GC and GC-MS it can be found out that the major compounds contained in liquid smoke, the product of humic acid cracking with 20-40 mesh catalyst at a temperature of 400°C were phenolic compounds (74.56%), and no carboxylic and carbonylic compounds as the major compounds. The activated clay can be used as the catalyst for humic acid cracking.

Constraining the Climates of Rocky Exoplanets

Elements ◽  
2021 ◽  
Vol 17 (4) ◽  
pp. 251-256 ◽  
Author(s):  
Thaddeus D. Komacek ◽  
Wanying Kang ◽  
Jacob Lustig-Yaeger ◽  
Stephanie L. Olson
Keyword(s):  
Climate Models ◽  
Oceanic Circulation ◽  
Modeling Tools ◽  
Astronomical Observations ◽  
Atmospheric Structure ◽  
Recent Advances ◽  
Insight Into ◽  
Made In

Numerical climate models originally developed for Earth have been adapted to study exoplanetary climates. This is allowing us to investigate the range of properties that might affect an exoplanet’s climate. The recent discovery, and upcoming characterization, of cosmically close rocky exoplanets opens the door toward understanding the processes that shape planetary climates, maybe also leading to insight into the persistent habitability of Earth itself. We summarize the recent advances made in understanding the climate of rocky exoplanets, including their atmospheric structure, chemistry, evolution, and atmospheric and oceanic circulation. We describe current and upcoming astronomical observations that will constrain the climate of rocky exoplanets and describe how modeling tools will both inform and interpret future observations.

scholarly journals EKSTRAKSI DAN PENENTUAN GUGUS FUNGSI ASAM HUMAT DARI PUPUK KOTORAN SAPI

2018 ◽  
Vol 1 (1) ◽  
pp. 30
Author(s):  
Nurlina Nurlina ◽  
Intan Syahbanu ◽  
Mirna Tersiana Tamnasi ◽  
Chyntia Nabela ◽  
Maria Desi Furnata
Keyword(s):  
Humic Acid ◽  
Functional Groups ◽  
Raw Material ◽  
Acid Extraction ◽  
Total Acidity ◽  
Cow Manure ◽  
Absorption Method ◽  
Aromatic Components

Cow manure fertilizer was used as raw material for the extraction of humic acid in this research. The aim of this research were  extraction of humic acid from cow manure fertilizer, characterization of functional groups based on FTIR spectra, and determination of humic acid functional groups. Humic acid extraction from cow manure used 0.050 M; 0.100 M; 0.250 M dan 0.500 M KOH solution. A cow manure fertilizer were shaken with KOH solution for 1; 2; 4 and 6 h. The quantitative determination of oxygen-containing functional groups of humic acid was conducted by titrimetri. The FTIR spectrum showed the presence of  –OH group and N-H stretching (bands 3361.46 cm-1); C-H aliphatic for CH2, CH3 (2946.52 cm-1 and 1442.24 cm-1); C=C aromatic components (1626.48 cm-1); COO- symmetric stretching (1521.71 cm-1); C-O stretching from –COOH (1229.74 cm-1). Total acidity value was 500 cmole.kg-1 (Baryta Absorption Method); carboxyl groups content was 250 cmole.kg-1 (Ca-Acetate Method); and phenol (OH) concentration was 250 cmole.kg-1. It can be concluded that humic acid successfully extracted from cow manure fertilizer using 0.250 KOH solution as extractant for 2 h, which has  yield of 4.486% humic acid.

scholarly journals Improvement of the Modified Dry-Cup Method for Determination of the Diffusion Coefficients of Gaseous Pollutants in Building Materials

2010 ◽  
Vol 305-306 ◽  
pp. 109-114 ◽  
Author(s):  
José J. Gonçalves ◽  
Gabriela V. Silva ◽  
Armando S. Santos ◽  
Eduardo O. Fernandes
Keyword(s):  
Diffusion Coefficients ◽  
Air Pollutants ◽  
Partition Coefficients ◽  
Passive Sampling ◽  
Building Materials ◽  
Sources And Sinks ◽  
Set Up ◽  
Made In

Diffusion and partition coefficients are key parameters for the characterization of building materials as sources and sinks of air pollutants indoors. A simple and rapid experimental method for direct measurement of the diffusion coefficient (D) was presented in a previous article [1]: the modified dry cup method. This method was based upon two existent methodologies, the passive sampling on Tenax TA and the dry cup method, proposed by Haghighat et al. [2]. In the present article, some improvements were made in the experimental set-up in order to obtain more precise results. The previous cup was modified by increasing the number of Tenax tubes, connected to the bottom of the cup, from one to five. The results obtained with both cups were compared. Measurements with single compounds and with three compounds simultaneously were compared in order to evaluate the influence of competition between molecules of different compounds.

Characterization of Heroin: A Preliminary Study

1970 ◽  
Vol 53 (6) ◽  
pp. 1137-1139
Author(s):  
M J Pro ◽  
R L Brunelle
Keyword(s):  
Neutron Activation Analysis ◽  
Activation Analysis ◽  
Chemical Analysis ◽  
Neutron Activation ◽  
Chemical Elements ◽  
Analytical Techniques ◽  
Preliminary Examination ◽  
Preliminary Study

Abstract Heroin samples from 100 actual cases were examined by multiple analytical techniques. After preliminary examination by microscopy and chemical analysis indicated similarity of questioned and known specimens, as many as 22 chemical elements were measured by neutron activation analysis and atomic absorption. Since illicit heroin is crudely produced, the qualitative elemental analysis is significant; however, more important for characterization purposes is the quantitative determination of the elements found because the concentration ranges for each element are extremely large.

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