HUMIC ACID-INDUCED ECHINOCYTE TRANSFORMATION IN HUMAN ERYTHROCYTES: CHARACTERIZATION OF MORPHOLOGICAL CHANGES AND DETERMINATION OF THE MECHANISM UNDERLYING DAMAGE

2000 ◽  
Vol 60 (3) ◽  
pp. 215-230 ◽  
Author(s):  
You-Cheng Hseu, Fung-Jou Lu, Larry
Keyword(s):  
Humic Acid ◽  
Morphological Changes ◽  
Human Erythrocytes

Characterization of a humic gel synthesized from an activated epoxy silica gel

2002 ◽  
Vol 90 (4) ◽  
Author(s):  
C. Barbot ◽  
K. Czerwinski ◽  
Gunnar Buckau ◽  
J. I. Kim ◽  
Valérie Moulin ◽  
...  
Keyword(s):  
Humic Acid ◽  
Silica Gel ◽  
Chemical Properties ◽  
Column Experiments ◽  
Surface Binding ◽  
Silica Gel Particles ◽  
And Chemical Properties ◽  
Covalently Bound

SummaryPurified humic acid has been covalently bound on activated epoxy silica gel particles. Determination of physical properties and chemical properties was conducted in order to characterize the material at different stages of the preparation. FTIR spectra and the PEC of the surface bound humic acid is very similar to that of humic acid starting material. This shows that the humic acid was not deteriorated during the surface binding process. This humic gel can be used as an analogue for sediment associated humic acid, with the advantage that covalently bound humic acid does not desorb, and thus allows for simple species separation between non-complexed and humic bound metal ions in batch and column experiments.

Use of two-color array pyrometry for characterization of combustion synthesis waves

2000 ◽  
Vol 15 (2) ◽  
pp. 572-580 ◽  
Author(s):  
U. Anselmi-Tamburini ◽  
F. Maglia ◽  
G. Spinolo ◽  
Z. A. Munir
Keyword(s):  
Activation Energy ◽  
Wave Propagation ◽  
High Temperature ◽  
Combustion Synthesis ◽  
Morphological Changes ◽  
Formation Of Cracks ◽  
High Temperature Reactions ◽  
Time Sequences

A two-color array pyrometer was used to investigate morphological developments on the surface of materials undergoing self-propagating high-temperature reactions. Time sequences of temperature spatial profiles during wave propagation were found to be complex in their nature and dynamics. They contain features that are interpreted in terms of morphological changes during the process. These features include formation of cracks or voids, expansion of the sample, and formation of droplets of metals on the surface. The use of the array pyrometer for determination of the activation energy of the combustion reaction between Zr and NiO is reported.

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.

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.

KAJIAN ADSORPSI Ag(S2O3)23- DALAM LIMBAH FOTOGRAFI PADA ADSORBEN KITIN DAN ASAM HUMAT TERIMOBILISASI PADA KITIN

2007 ◽  
Vol 9 (2) ◽  
pp. 58
Author(s):  
Fitri Khoerunnisa ◽  
Sri Juari Santosa ◽  
Eko Sri Kunarti
Keyword(s):  
Hydrogen Bonding ◽  
Humic Acid ◽  
Peat Soil ◽  
Crab Shell ◽  
Dominant Mechanism ◽  
Initial Concentration ◽  
Adsorption Condition ◽  
Synthetic Solution

This work was started with isolation of humic acid from peat soil and chitin from crab shell, immobilization of humic acid on chitin, and characterization of adsorbents of C and HAC. Optimum condition was studied by interacting the adsorbents with Ag(S2O3)23- in a synthetic solution on various  of pH from 2 to 10. Adsorption rate was studied by interacting the adsorbent with Ag(S2O3)23- in the synthetic solution on various time from 2 to 120 minutes. The determination of the energy and the capacity of adsorption were studied by interacting the adsorbent with Ag(S2O3)23- on various initial concentration from 2 to 75 ppm. Moreover, the mechanism of adsorption was studied by applying a sequential desorption using H2O, Na2EDTA 0.1 M, KSCN 0.5 M, and KOH 1 M. The adsorption of Ag(S2O3)23- in photography wastewater on C and on HAC were studied at the same condition as obtained for the synthetic solution. The result showed that pH 2 was the optimum adsorption condition for Ag(S2O3)23- in the synthetic solution on both C and HAC adsorbents. Ag(S2O3)23- in the synthetic solution was chemically adsorbed on C and on HAC, involving energy adsorption of 22.74–23.30 kJ/mole, respectively. Adsorption of Ag(S2O3)23- on C was faster than that on HAC with the rate constants for adsorbent C and HAC were 73 x 10-4 and 46 x 10-4 minute-1, respectively. Adsorption capacity of Ag(S2O3)23- on C and on HAC were 2.107 x 10-4 and 1.818 x 10-4 mole/g, respectively. The amount of Ag(S2O3)23- in photography wastewater that was adsorbed on C and on HAC were 13.52 and 12.47 mg/L, respectively. The hydrogen bonding and ion exchange were the dominant mechanism of adsorption.Key words: Ag(S2O3)23-, adsorption, chitin, immobilization, humic acid.

Characterization of Impressed Current Technique to Model Corrosion of Reinforcement in Concrete

2020 ◽  
Vol 11 (1) ◽  
pp. 93-99
Author(s):  
Abu Zakir Morshed ◽  
Sheikh Shakib ◽  
Tanzim Jahin
Keyword(s):  
Immersion Time ◽  
Chloride Content ◽  
Engineering Science ◽  
Coastal Regions ◽  
Faraday’S Law ◽  
Current Technique ◽  
Corrosion Cell ◽  
Impressed Current

Corrosion of reinforcement is an important durability concern for the structures exposed to coastal regions. Since corrosion of reinforcement involves long periods of time, impressed current technique is usually used to accelerate the corrosion of reinforcement in laboratories. Characterization of impressed current technique was the main focus of this research,which involved determination of optimum chloride content and minimum immersion time of specimens for which the application of Faraday’s law could be efficient. To obtain optimum chloride content, the electrolytes in the corrosion cell were prepared similar to that of concrete pore solutions. Concrete prisms of 200 mm by 200 mm by 300 mm were used to determine the minimum immersion time for saturation. It was found that the optimum chloride content was 35 gm/L and the minimum immersion time for saturation was 140 hours. Accounting the results, a modified expression based on Faraday’s law was proposed to calculate weight loss due to corrosion. Journal of Engineering Science 11(1), 2020, 93-99

The Determination of Sense via Deleuze and Blanchot: Paradoxes of the Habitual, the Immemorial, and the Eternal Return

2008 ◽  
Vol 2 (2) ◽  
pp. 155-177 ◽  
Author(s):  
Eugene Brently Young
Keyword(s):  
Eternal Return

Eternal return is the paradox that accounts for the interplay between difference and repetition, a dynamic at the heart of Deleuze's philosophy, and Blanchot's approach to this paradox, even and especially through what it elides, further illuminates it. Deleuze draws on Blanchot's characterisations of difference, forgetting, and the unlivable to depict the ‘sense’ produced via eternal return, which, for Blanchot, is where repetition implicates or ‘carries’ pure difference. However, for Deleuze, difference and the unlivable are also developed by the living repetition or ‘contraction’ of habit, which results in his distinctive characterization of ‘force’, ‘levity’, and sense in eternal return.

Characterization of dissolved organic matter (DOM) extracted from soils by hot water percolation (HWP)

2010 ◽  
Vol 59 (1) ◽  
pp. 99-108 ◽  
Author(s):  
M. Takács ◽  
Gy. Füleky
Keyword(s):  
Organic Matter ◽  
Humic Acid ◽  
Natural Organic Matter ◽  
Extraction Methods ◽  
Soil Samples ◽  
Hot Water ◽  
Soil Extracts ◽  
Water Percolation ◽  
Soil Humic Acid

The Hot Water Percolation (HWP) technique for preparing soil extracts has several advantages: it is easily carried out, fast, and several parameters can be measured from the same solution. The object of this study was to examine the possible use of HWP extracts for the characterization of soil organic matter. The HPLC-SEC chromatograms, UV-VIS and fluorescence properties of the HWP extracts were studied and the results were compared with those of the International Humic Substances Society (IHSS) Soil Humic Acid (HA), IHSS Soil Fulvic Acid (FA) and IHSS Suwannee Natural Organic Matter (NOM) standards as well as their HA counterparts isolated by traditional extraction methods from the original soil samples. The DOM of the HWP solution is probably a mixture of organic materials, which have some characteristics similar to the Soil FA fractions and NOM. The HWP extracted organic material can be studied and characterized using simple techniques, like UV-VIS and fluorescence spectroscopy.

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