scholarly journals The Identification of Polyester Fibers Dyed with Disperse Dyes for Forensic Purposes

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 613 ◽  
Author(s):  
Daria Śmigiel-Kamińska ◽  
Jan Pośpiech ◽  
Joanna Makowska ◽  
Piotr Stepnowski ◽  
Jolanta Wąs-Gubała ◽  
...  
Keyword(s):  
Chemical Structure ◽  
Forensic Analysis ◽  
Disperse Dyes ◽  
Spectroscopic Methods ◽  
Spectroscopic Techniques ◽  
Specific Chemical ◽  
Synthetic Fibers ◽  
Detection Systems ◽  
Chromatographic Techniques ◽  
Polyester Fibers

In forensic laboratories, the most commonly analyzed microtraces are microscopic fragments of single fibers. One of the main goals of the examination of fragments of fibers a few millimeters long is to determine their characteristic physicochemical properties and compare them with fibers originating from a known source (e.g., a suspect’s clothes). The color and dyes of fiber microtraces play an important role in their research and evaluation, being analyzed by means of microscopic, spectroscopic, and chromatographic methods. The results of examinations conducted with the use of spectroscopic techniques might be ambiguous due to overlapping bands of absorption and the transmission and dispersion of electromagnetic radiation corresponding to the specific chemical structure of the fibers and their dyes. For this reason, it is very important to improve currently available spectroscopic methods and/or to propose new ones that allow evidential materials to be analyzed in a much more reliable way. In this review, the possibility of the use of chromatographic techniques with different detection systems for such analyses is underlined. This review covers the different analytical methods used in the forensic analysis of polyester fibers dyed with disperse dyes. Polyester fibers occupy the first position among synthetic fibers in their use for a variety of purposes, and disperse dyes are commonly applied for dyeing them.

Synthesis of a New Dioxaspiro[bicyclo[3.3.1]nonane-oxabicyclo[6.2.0]deca- 1(10),8-dien-4-one Derivative Using Some Chemical Strategies

2020 ◽  
Vol 17 (5) ◽  
pp. 393-402
Author(s):  
Figueroa-Valverde Lauro ◽  
Rosas-Nexticapa Marcela ◽  
Lopez-Ramos Maria ◽  
Diaz Cedillo Francisco ◽  
Mateu-Armand Virginia ◽  
...  
Keyword(s):  
Elemental Analysis ◽  
Chemical Structure ◽  
Spectroscopic Techniques ◽  
Easy Method ◽  
Chemical Strategies

There are several protocols for the preparation of bicyclic derivatives; however, some methods use dangerous and require special conditions. The aim of this study was to synthesize a new Dioxaspiro[ bicyclo[3.3.1]nonane-oxabicyclo[6.2.0]-deca-1(10), 8-dien-4-one (compound 8). Compound 8 was prepared using some reactions such as; i) etherification, ii) reduction, iii) amidation, iv) imination and v) 2+2 addition. The chemical structure of 8 and its intermediaries were completely characterized by spectroscopic techniques and elemental analysis. The synthesis showed a yield of 85% for compound 8. In this study, an easy method for the preparation of compound 8 is reported.

scholarly journals Discovery of a natural cyan blue: A unique food-sourced anthocyanin could replace synthetic brilliant blue

2021 ◽  
Vol 7 (15) ◽  
pp. eabe7871
Author(s):  
Pamela R. Denish ◽  
Julie-Anne Fenger ◽  
Randall Powers ◽  
Gregory T. Sigurdson ◽  
Luca Grisanti ◽  
...  
Keyword(s):  
Protein Design ◽  
Food Industry ◽  
Chemical Structure ◽  
Nutritional Value ◽  
Blue Dye ◽  
Spectroscopic Techniques ◽  
Design Tools ◽  
Enzymatic Transformation ◽  
Food And Beverage ◽  
The Subject

The color of food is critical to the food and beverage industries, as it influences many properties beyond eye-pleasing visuals including flavor, safety, and nutritional value. Blue is one of the rarest colors in nature’s food palette—especially a cyan blue—giving scientists few sources for natural blue food colorants. Finding a natural cyan blue dye equivalent to FD&C Blue No. 1 remains an industry-wide challenge and the subject of several research programs worldwide. Computational simulations and large-array spectroscopic techniques were used to determine the 3D chemical structure, color expression, and stability of this previously uncharacterized cyan blue anthocyanin-based colorant. Synthetic biology and computational protein design tools were leveraged to develop an enzymatic transformation of red cabbage anthocyanins into the desired anthocyanin. More broadly, this research demonstrates the power of a multidisciplinary strategy to solve a long-standing challenge in the food industry.

Mariannaeapyrone -a New Inhibitor of Thromboxane A2 Induced Platelet Aggregation

2001 ◽  
Vol 56 (1-2) ◽  
pp. 106-110 ◽  
Author(s):  
Kerstin Fabian ◽  
Timm Anke ◽  
Olov Sterner
Keyword(s):  
Platelet Aggregation ◽  
Chemical Structure ◽  
Thromboxane A2 ◽  
Human Platelets ◽  
Selective Inhibitor ◽  
Spectroscopic Techniques ◽  
Fungal Metabolite ◽  
Antimicrobial Effects ◽  
The Common ◽  
Induced Aggregation

Abstract Mariannaeapyrone ((E)-2-(1,3,5,7-tetramethyl-5-nonenyl)-3,5-dimethyl-6-hydroxy-4H-pyran-4-one) is a new fungal metabolite isolated from fermentations of the common mycophilic deuteromycete Mariannaea elegans. The chemical structure of the 4-pyrone was determined by spectroscopic techniques. Mariannaeapyrone is a selective inhibitor of the thromboxane A2 induced aggregation of human platelets, whereas only weak cytotoxic and antimicrobial effects could be observed.

scholarly journals Spectroscopic Methods in the Evaluation of Modified Vegetable Base Oils from Crambe abyssinica

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3243 ◽  
Author(s):  
Michał Szmatoła ◽  
Justyna Chrobak ◽  
Rafał Grabowski ◽  
Jolanta Iłowska ◽  
Julia Woch ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Vegetable Oil ◽  
Supercritical Co2 ◽  
Spectroscopic Methods ◽  
Spectroscopic Techniques ◽  
Chemical Transformations ◽  
Chemical Changes ◽  
Crambe Abyssinica ◽  
Oxidation Processes ◽  
Ft Ir

Raw vegetable oil from Crambe abyssinica was subjected to oxidative treatment to enhance its viscosity. The oxidation processes were carried out in the presence of N-hydroxyphthalimide with or without supercritical CO2 as a solvent. Four spectroscopic techniques (Raman, UV-VIS, FT-IR, NMR) were applied to assess the chemical changes taking place during the oxidation. Raman and NMR spectroscopy proved best in the assessment of the chemical transformations leading to increased viscosity of the modified vegetable oil.

scholarly journals Purification, Characterization, and Antioxidant Activity of Daucosterol and Stigmasterol from Prangos ferulacea

2020 ◽  
Vol 10 (2) ◽  
pp. 2174-2180
Keyword(s):  
Antioxidant Activity ◽  
Structure Elucidation ◽  
Antiradical Activity ◽  
Bioactive Metabolites ◽  
Spectroscopic Techniques ◽  
Chromatographic Techniques ◽  
Phytochemical Investigation ◽  
Antioxidant Agents ◽  
Wide Range ◽  
Ft Ir

The genus Prangos is traditionally used for medicinal and food purposes. This genus contains a wide range of bioactive metabolites. In this work, phytochemical investigation and antioxidant activity evaluation of Prangos ferulacea were carried out. Chromatographic techniques were employed for the purification of extracts components. Spectroscopic techniques such as NMR, FT-IR, together with elemental analysis, were used for the structure elucidation of isolated compounds. Stigmasterol, daucosterol, and salicylic acid were purified and identified. Isolated compounds showed moderate to high antiradical activity in DPPH antioxidant assay. Results indicated the potential of P. ferulacea as a source of steroid and their glycosides and also its possible applications as antioxidant agents.

Oxidative Aging of Natural Rubber Vulcanizates. Part III. Crosslink Scission in Monosulfidic Networks

1969 ◽  
Vol 42 (3) ◽  
pp. 924-935 ◽  
Author(s):  
T. Colclough ◽  
J. I. Cunneen ◽  
G. M. C. Hrggins
Keyword(s):  
Natural Rubber ◽  
Physical Properties ◽  
Chemical Structure ◽  
Spectroscopic Methods ◽  
Chemical Probes ◽  
Conjugated Diene ◽  
Strain Measurements ◽  
Oxidative Aging ◽  
Tert Butyl Hydroperoxide ◽  
Natural Rubber Vulcanizates

Abstract A natural rubber vulcanizate containing almost entirely monosulfidic crosslinks was oxidized in oxygen and with tert-butyl hydroperoxide. The changes in physical properties due to oxidation were followed by stress—strain measurements, and the changes in chemical structure were investigated with chemical probes, and by spectroscopic methods. The results show that when the oxidized vulcanizates are heated at 75° C, the monosulfidic crosslinks are broken, that crosslinks containing two sulfur atoms are formed, and that conjugated diene and triene structures are introduced into the main polyisoprene chains.

scholarly journals A New 3-Prenyl-2-flavene and Other Extractives from Baphia massaiensis and Their Antimicrobial Activities

2018 ◽  
Vol 13 (4) ◽  
pp. 1934578X1801300 ◽  
Author(s):  
Ngonye Keroletswe ◽  
Runner R. T. Majinda ◽  
Ishmael B. Masesane
Keyword(s):  
Escherichia Coli ◽  
2D Nmr ◽  
Antimicrobial Activities ◽  
Spectroscopic Techniques ◽  
Good Activity ◽  
Gram Negative ◽  
E Coli ◽  
Chromatographic Techniques ◽  
Inhibition Zones ◽  
First Time

One new 3-prenyl-2-flavene, named baphiflavene A, 1, and eleven known compounds, 2-12, were isolated and reported for the first time from Baphia massaiensis using several chromatographic techniques. Their structures were elucidated using different spectroscopic techniques; 1D and 2D-NMR, HRMS, GC-MS, UV/Vis, FTIR and by comparison with literature data. The isolates were tested against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli and Candida albicans to establish their preliminary antimicrobial activities. The results revealed that compound 1 had moderate activities against both Gram positive ( B. subtilis and S. aureus) and Gram negative ( E. coli and P. aeruginosa) bacteria, and good activity against C. albicans with inhibition zones of 10–23 mm (compared to 19 mm for chloramphenicol and miconazole standards). To the best of our knowledge, this is the first phytochemical work reported on Baphia massaiensis.

Synthesis of azo disperse dyes containing pyridine ring for dyeing polyester and polyacrylic fibres

2016 ◽  
Vol 45 (1) ◽  
pp. 10-17 ◽  
Author(s):  
A.A. Fadda ◽  
N.S. Abbas
Keyword(s):  
Pyridine Ring ◽  
Cycloaddition Reaction ◽  
Disperse Dyes ◽  
Ethyl Vinyl Ether ◽  
Spectroscopic Techniques ◽  
Ethyl Vinyl ◽  
Content Type ◽  
Dyeing Performance ◽  
Azo Disperse Dyes ◽  
Derivatives Of

Purpose – The purpose of this paper is to discuss the synthesis of new azo disperse dyes containing pyridine ring for dyeing acetate polyester and other fibres. Design/methodology/approach – Cycloaddition reaction of 3-formylchromone (Compound 1) with ethyl vinyl ether (Compound 2) afforded 3-ethoxy-4,4a-dihyro-3H,10H-pyrano[4,3-b]chromen-10-one (Compound 3). Reaction of 3 with aqueous ammonium sulphite in ethanol furnishes 3-(2-hydroxybenzoyl)pyridine (Compound 5). Compound 5 was fully characterised by spectroscopic techniques. Ten arylazo derivatives of Compound 6 have been prepared for use as dyestuffs. The effect of the nature and orientation of substituents in the diazonium component on the colour of azo dyes is discussed. Dyeing performance of the dyes on different fibres has also been assessed. Findings – Most of the dyes showed good affinity to polyester fibres. On the other hand, polyacrylic fibres were only stained to weak shades. Originality/value – No details regarding the synthesis and dyeing performance of such dyes are reported before in the literature.

Corrosion Control of Cu-10Al-10Ni and Cu-10Al-10Zn Alloys in Seawater Environment by Some Ethoxylated Tolyltriazole Derivatives

2017 ◽  
Vol 231 (6) ◽  
Author(s):  
H. Nady ◽  
M.M. El-Rabiei ◽  
M.A. Migahed ◽  
M. Fathy
Keyword(s):  
Chemical Structure ◽  
Nonionic Surfactants ◽  
Alloying Elements ◽  
Spectroscopic Techniques ◽  
Corrosion Control ◽  
New Family ◽  
Seawater Environment ◽  
Chain Lengths ◽  
Protection Of Metals

AbstractProtection of metals from being damaged under the effect of corrosion occurs by several methods like the addition of alloying elements or inhibitors. A new family of some nonionic surfactants based on tolyltriazole derivatives (TTAs) having various ethoxyl chain lengths were prepared and their chemical structure was elucidated by using different spectroscopic techniques (FTIR and

Comparison of spectroscopic methods in the detection of silicone-based condom lubricant evidence

2020 ◽  
Vol 12 (5) ◽  
pp. 657-665 ◽  
Author(s):  
Céline Burnier ◽  
Wilhelm van Bronswijk ◽  
Geneviève Massonnet
Keyword(s):  
Spectroscopic Methods ◽  
Spectroscopic Techniques

Different spectroscopic techniques are compared and discussed for the analysis of silicone-based condom lubricants for forensic purposes.

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