Practice for Determination of Structural Features in Polyolefins and Polyolefin Copolymers by Infrared Spectrophotometry (FT-IR)

2021 ◽  
Author(s):  
Keyword(s):  
Structural Features ◽  
Infrared Spectrophotometry ◽  
Ft Ir

DETERMINATION OF THE TYPE OF A SINGLE-USE GRENADE LAUNCHER BASED ON ITS COMPOSITE PARTS AND FRAGMENTS OF REACTIVE GRENADE FOUND AT THE PLACE OF ACCIDENT

2017 ◽  
Vol 17 ◽  
pp. 245-252
Author(s):  
V. V. Somov
Keyword(s):  
Combustion Chamber ◽  
Structural Features ◽  
Outlet Section ◽  
Technical Expertise ◽  
Jet Engine ◽  
Size Ofthe ◽  
Single Use ◽  
Nozzle Block ◽  
Considerable Damage

In carrying out an investigation into the explosion, among others, the investigative version of the use of a single-use reactive grenade launcher is being considered. The most common for criminal explosions are applied grenade launchers RPG-18, RPG-22, RPG-26. Their use is due to a number of such properties as small size and weight, which makes it possible to transfer them covertly, the range of the shot significantly exceeding the range of the hand grenade throw, the high detonating effect of the rocket grenade explosion. The single-use rocket launchers are generally of the same design. Their differences are in the features of the components construction and dimensional characteristics, which are given in the article. On the basis of expert practice, details ofgrenade launchers that remain at the site of the explosion and have the least damage are determined. These details are the objects of investigation of the explosion technical expertise. These objects include launchers of grenade launchers and rocket parts ofjet grenades. The design features of the launchers, their dimensional characteristics and marking symbols make it possible to determine their belonging to a specific type of jet grenade launchers. Missile parts of jet grenades differ in the form of the combustion chamber of the jet engine, nozzle, in the size ofthe outlet section of the nozzle, in the form and size of the stabilizerfeathers. To determine the belonging of the rocket part of the grenade to a specific type ofjet grenade launcher, it’s necessary to establish a set of structural features and dimensional characteristics. At considerable damage of the combustion chamber of the jet engine, as a rule, the nozzle block remains intact that allows to define diameter of critical section of a nozzle, and on it to establish type of the used single-use grenade launcher.

Authentication of the Ancient Easel / Paintings Through Materials Identification from the Polychrome Layers II. Analysis by Means of the FT-IR Spectrophotometry

2008 ◽  
Vol 59 (4) ◽  
Author(s):  
Irina Crina Anca Sandu ◽  
Constantin Luca ◽  
Ion Sandu ◽  
Viorica Vasilache ◽  
Mikiko Hayashi
Keyword(s):  
Degradation Rate ◽  
Animal Glue ◽  
Painting Materials ◽  
Ageing Rate ◽  
Ir Spectrophotometry ◽  
Private And Public ◽  
Ft Ir

This is the second paper belonging to a study concerning the authentication of ancient easel-paintings, on canvas and wood support, from private and public collections, by using the FT-IR spectrophotometry technique for the analysis of the painting materials. Different pigments, egg binders, caseins and animal glue, often found in ancient easel-paintings on wood or canvas, have been used as standards for establishing the ageing rate of the paintings by correlation with the dates presented in the first note. The determination of the degradation rate of the painting materials is an important archaeometric characteristic used in authentication.

scholarly journals Chitosan hydrogel/silk fibroin/Mg(OH)2 nanobiocomposite as a novel scaffold with antimicrobial activity and improved mechanical properties

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Reza Eivazzadeh-Keihan ◽  
Fateme Radinekiyan ◽  
Hooman Aghamirza Moghim Aliabadi ◽  
Sima Sukhtezari ◽  
Behnam Tahmasebi ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Cell Viability ◽  
Silk Fibroin ◽  
Analytical Techniques ◽  
Structural Features ◽  
Mechanical Tests ◽  
Chitosan Hydrogel ◽  
Biological Capacity ◽  
Ft Ir ◽  
Novel Scaffold

AbstractHerein, a novel nanobiocomposite scaffold based on modifying synthesized cross-linked terephthaloyl thiourea-chitosan hydrogel (CTT-CS hydrogel) substrate using the extracted silk fibroin (SF) biopolymer and prepared Mg(OH)2 nanoparticles was designed and synthesized. The biological capacity of this nanobiocomposite scaffold was evaluated by cell viability method, red blood cells hemolytic and anti-biofilm assays. According to the obtained results from 3 and 7 days, the cell viability of CTT-CS/SF/Mg(OH)2 nanobiocomposite scaffold was accompanied by a considerable increment from 62.5 to 89.6% respectively. Furthermore, its low hemolytic effect (4.5%), and as well, the high anti-biofilm activity and prevention of the P. aeruginosa biofilm formation confirmed its promising hemocompatibility and antibacterial activity. Apart from the cell viability, blood biocompatibility, and antibacterial activity of CTT-CS/SF/Mg(OH)2 nanobiocomposite scaffold, its structural features were characterized using spectral and analytical techniques (FT-IR, EDX, FE-SEM and TG). As well as, given the mechanical tests, it was indicated that the addition of SF and Mg(OH)2 nanoparticles to the CTT-CS hydrogel could improve its compressive strength from 65.42 to 649.56 kPa.

scholarly journals Influence of a Natural Plant Antioxidant on the Ageing Process of Ethylene-norbornene Copolymer (Topas)

2021 ◽  
Vol 22 (8) ◽  
pp. 4018
Author(s):  
Anna Masek ◽  
Angelika Plota
Keyword(s):  
Mechanical Properties ◽  
Food Packaging ◽  
Colour Change ◽  
Good Alternative ◽  
Plant Origin ◽  
Aging Behavior ◽  
Current State ◽  
Ft Ir ◽  
Potential Use

In the field of polymer technology, a variety of mainly synthetic additives are used to stabilize the materials during processing. However, natural compounds of plant origin can be a green alternative to chemicals such as synthetic polyphenols. An analysis of the effect of hesperidin on the aging behavior of ethylene-norbornene copolymer was performed. The evaluation of changes in the tested samples was possible by applying the following tests: determination of the surface energy and OIT values, mechanical properties analysis, colour change measurements, FT-IR and TGA analyses. The obtained results proved that hesperidin can be effectively used as natural stabilizer for polymers. Furthermore, as a result of this compound addition to Topas-silica composites, their surface and physico-mechanical properties have been improved and the resistance to aging significantly increased. Additionally, hesperidin can act as a dye or colour indicator and only few scientific reports describe a possibility of using flavonoids to detect changes in products during their service life, e.g., in food packaging. In the available literature, there is no information about the potential use of hesperidin as a stabilizer for cycloolefin copolymers. Therefore, this approach may contribute not only to the current state of knowledge, but also presents an eco-friendly solution that can be a good alternative to synthetic stabilizers.

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