Redox and complexation chemistry of the CrVI/CrV/CrIV-d-glucuronic acid system

2010 ◽  
Vol 39 (9) ◽  
pp. 2204 ◽  
Author(s):  
Juan Carlos González ◽  
Silvia García ◽  
Sebastián Bellú ◽  
Juan Manuel Salas Peregrín ◽  
Ana María Atria ◽  
...  
Keyword(s):  
Glucuronic Acid ◽  
Acid System ◽  
Complexation Chemistry

Redox and complexation chemistry of the CrVI/CrV–d-galacturonic acid system

2004 ◽  
pp. 2288-2296 ◽  
Author(s):  
Juan C. González ◽  
Verónica Daier ◽  
Silvia García ◽  
Bernard A. Goodman ◽  
Ana M. Atria ◽  
...  
Keyword(s):  
Galacturonic Acid ◽  
Acid System ◽  
Complexation Chemistry

Redox and complexation chemistry of the CrVI/CrV-d-glucaric acid system

2014 ◽  
Vol 43 (24) ◽  
pp. 9242 ◽  
Author(s):  
María Florencia Mangiameli ◽  
Juan Carlos González ◽  
Sebastián Bellú ◽  
Fernando Bertoni ◽  
Luis F. Sala
Keyword(s):  
Acid System ◽  
Glucaric Acid ◽  
Complexation Chemistry

CHROMATOGRAPHIC STUDIES ON 131I-COMPOUNDS IN FAECES AND BILE

1964 ◽  
Vol 47 (2) ◽  
pp. 343-352
Author(s):  
B. Blomstedt ◽  
H. Y. Neujahr
Keyword(s):  
Intravenous Administration ◽  
Glucuronic Acid ◽  
Free Triiodothyronine ◽  
Considerable Part ◽  
Human Faeces ◽  
Total Excretion

ABSTRACT The occurrence of 131I-compounds in human faeces was studied after intravenous administration of 131I-thyroxine. The excretion of the radioactivity during 12 days ranged from 7.8 to 32.1 per cent of the dose administered with a mean of 16.0 (± 1.76). The radioactivity in the faeces was derived from free 131I-thyroxine. The total amount of faeces did not seem to influence the total excretion of the dose administered. After administration of 131I-triiodothyronine to rats and humans, triiodothyronine occurred in the bile mainly conjugated with glucuronic acid, but a considerable part of the radioactivity was found in diiodotyrosine. The radioacivity of human faeces after the administration of 131I-triiodothyronine was derived from free triiodothyronine. After injection of 131I-diiodotyrosine only labelled iodide was detected in the bile of rats. In the bile of humans most of the radioactivity was derived from iodide, and a small part of it was found in diiodotyrosine.

A Review of Wet Etch Formulas for Silicon Semiconductor Failure Analysis

1996 ◽  
Author(s):  
T.W. Lee
Keyword(s):  
Failure Analysis ◽  
Literature Search ◽  
Wet Etching ◽  
Second Step ◽  
Environmental Concerns ◽  
Acid System ◽  
Graphical Data ◽  
Selective Etch ◽  
Chromium Compounds ◽  
Wet Etch

Abstract WET ETCHING is an important part of the failure analysis of semiconductor devices. Analysis requires etches for the removal, delineation by decoration or differential etching, and study of defects in layers of various materials. Each lab usually has a collection of favored etch recipes. Some of these etches are available premixed from the fab chemical supply. Some of these etches may be unique, or even proprietary, to your company. Additionally, the lab etch recipe list will usually contain a variety of classical "named etches". These recipes, such as Dash Etch, have persisted over time. Although well-reported in the literature, lab lists may not accurately represent these recipes, or contain complete and accurate instructions for their use. Time seems to have erased the understanding of the purpose of additives such as iodine, in some of these formulas. To identify the best etches and techniques for a failure analysis operations, a targeted literature review of articles and patents was undertaken. It was a surprise to find that much of the work was quite old, and originally done with germanium. Later some of these etches were modified for silicon. Much of this work is still applicable today. Two main etch types were found. One is concerned with the thinning and chemical polishing of silicon. The other type is concerned with identifying defects in silicon. Many of the named etches were found to consist of variations in a specific acid system. The acid system has been well characterized with ternary diagrams and 3-D surfaces. The named etches were plotted on this diagram. The original formulas and applications of the named etches were traced to assure accuracy, so that the results claimed by the original authors, may be reproduced in today's lab. The purpose of this paper is to share the condensed information obtained during this literature search. Graphical data has been corrected for modem dimensions. Selectivities have been located and discussed. The contents of more than 25 named etches were spreadsheeted. It was concluded that the best approach to delineation is a two-step etch, using uncomplicated and well-characterized standard formulas. The first step uses a decoration or differential etch technique to define the junctions. Formulations for effective decoration etches were found to be surprisingly simple. The second step uses a selective etch to define the various interconnections and dielectric layers. Chromium compounds can be completely eliminated from these formulas, to meet environmental concerns. This work, originally consisting of 30 pages with 106 references, has been condensed to conform with the formatting requirements of this publication.

Binding of lead and copper(II) cations to hemicelluloses of rye bran

1986 ◽  
Vol 51 (10) ◽  
pp. 2250-2258 ◽  
Author(s):  
Rudolf Kohn ◽  
Zdena Hromádková ◽  
Anna Ebringerová
Keyword(s):  
Uronic Acid ◽  
Equilibrium Solution ◽  
Glucuronic Acid ◽  
The Other ◽  
Carboxyl Groups ◽  
Stoichiometric Ratio ◽  
Molar Ratios ◽  
Free Ions ◽  
Uronic Acid Content ◽  
The Relationship

Several fractions of acid hemicelluloses isolated from rye bran were characterized by molar ratios of saccharides (D-Xyl, L-Ara, D-Glc, D-Gal) and 4-O-methyl-D-glucuronic acid and protein content. Binding of Pb2+ and Cu2+ ions to these acid polysaccharides was considered according to function (M)b = f([M2+]f), expressing the relationship between the amount of metal (M)b bound to 1 g of the substance and the concentration of free ions [M2+]f in the equilibrium solution and according to the association degree β of these cations with carboxyl groups of uronic acid at a stoichiometric ratio of both components in the system under investigation. Acid hemicelluloses contained only a very small portion of uronic acid ((COOH) 0.05-0.18 mmol g-1); the model polysaccharide, 4-O-methyl-D-glucurono-D-xylan of beech, was substantially richer in uronic acid content ((COOH) 0.73 mmol g-1). Consequently, the amount of lead and copper bound to acid hemicelluloses is very small ((M)b 0.017-0.025 mmol g-1) at [M2+]f = 0.10 mmol l-1. On the other hand, much greater amount of cations ((M)f 0.09-0.10 mmol g-1) was bound to the glucuronoxylan. The association degree β was like with the majority of samples (β = 0.31-0.38). The amount of lead and copper(II) bound to acid hemicelluloses from rye bran is several times lower than that bound to dietary fiber isolated from vegetables (cabbage, carrot), rich in pectic substances.

scholarly journals Detection of Acetaminophen and Its Glucuronide in Fingerprint by SALDI Mass Spectrometry Using Zeolite and Study of Time-Dependent Changes in Detected Ion Amount

Analytica ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 66-75
Author(s):  
Toshiki Horikoshi ◽  
Chihiro Kitaoka ◽  
Yosuke Fujii ◽  
Takashi Asano ◽  
Jiawei Xu ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Glucuronic Acid ◽  
Laser Desorption ◽  
The Body ◽  
Time Dependent ◽  
Laser Desorption Ionization ◽  
Fingerprint Analysis ◽  
Desorption Ionization ◽  
Acid Conjugate ◽  
Over Time

The ingredients of an antipyretic (acetaminophen, AAP) and their metabolites excreted into fingerprint were detected by surface-assisted laser desorption ionization (SALDI) mass spectrometry using zeolite. In the fingerprint taken 4 h after AAP ingestion, not only AAP but also the glucuronic acid conjugate of AAP (GAAP), caffeine (Caf), ethenzamide (Eth), salicylamide (Sala; a metabolite of Eth), and urea were detected. Fingerprints were collected over time to determine how the amounts of AAP and its metabolite changed with time, and the time dependence of the peak intensities of protonated AAP and GAAP was measured. It was found that the increase of [GAAP+H]+ peak started later than that of [AAP+H]+ peak, reflecting the metabolism of AAP. Both AAP and GAAP reached maximum concentrations approximately 3 h after ingestion, and were excreted from the body with a half-life of approximately 3.3 h. In addition, fingerprint preservation was confirmed by optical microscopy, and fingerprint shape was retained even after laser irradiation of the fingerprint. Our method may be used in fingerprint analysis.

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