Diquaternary Ammonium Compounds in Zeolite Synthesis: Cyclic and PolycyclicN-Heterocycles Connected by Methylene Chains

2009 ◽  
Vol 131 (3) ◽  
pp. 1092-1100 ◽  
Author(s):  
Anna Jackowski ◽  
Stacey I. Zones ◽  
Son-Jong Hwang ◽  
Allen W. Burton
Keyword(s):  
Zeolite Synthesis ◽  
Ammonium Compounds ◽  
Diquaternary Ammonium

Diquaternary Ammonium Compounds as Transfection Agents

2001 ◽  
Vol 12 (2) ◽  
pp. 258-263 ◽  
Author(s):  
Howard S. Rosenzweig ◽  
Vera A. Rakhmanova ◽  
Robert C. MacDonald
Keyword(s):  
Ammonium Compounds ◽  
Diquaternary Ammonium

Computational elucidation of aging time effect on zeolite synthesis selectivity in the presence of water and a diquaternary ammonium iodide

2021 ◽  
Author(s):  
Bahram Ghanbari ◽  
Fatemeh Kazemi Zangeneh ◽  
German Sastre ◽  
Maryam Moeinian ◽  
sina marhabaie ◽  
...  
Keyword(s):  
Aging Time ◽  
Time Effect ◽  
Zeolite Synthesis ◽  
Ammonium Iodide ◽  
Structure Directing Agent ◽  
Organic Structure ◽  
Diquaternary Ammonium

An example of zeolite selectivity (MFI  MOR) driven by synthesis aging time has been studied. Using N,N,N',N'-tetramethyl-N,N'-dipropyl-ethylenediammonium diiodide (TMDP) as organic structure-directing agent (OSDA), the zeolite phases obtained at...

Determination of quaternary ammonium compounds in food products by the method of ultra-performance liquid chromatography/high resolution mass-spectrometry

2020 ◽  
Vol 86 (8) ◽  
pp. 23-31
Author(s):  
V. G. Amelin ◽  
D. S. Bolshakov
Keyword(s):  
Mass Spectrometry ◽  
High Resolution ◽  
Quaternary Ammonium ◽  
High Resolution Mass Spectrometry ◽  
Food Products ◽  
Quaternary Ammonium Compounds ◽  
High Resolution Mass ◽  
Ammonium Compounds ◽  
Resolution Mass

The goal of the study is developing a methodology for determination of the residual amounts of quaternary ammonium compounds (QAC) in food products by UHPLC/high-resolution mass spectrometry after water-acetonitrile extraction of the determined components from the analyzed samples. The identification and determination of QAC was carried out on an «UltiMate 3000» ultra-high-performance liquid chromatograph (Thermo Scientific, USA) equipped with a «maXis 4G» high-resolution quadrupole-time-of-flight mass spectrometric detector and an ion spray «ionBooster» source (Bruker Daltonics, Germany). Samples of milk, cheese (upper cortical layer), dumplings, pork, chicken skin and ground beef were used as working samples. Optimal conditions are specified for chromatographic separation of the mixture of five QAC, two of them being a mixture of homologues with a linear structure (including isomeric forms). The identification of QAC is carried out by the retention time, exact mass of the ions, and coincidence of the mSigma isotopic distribution. The limits for QAC detection are 0.1 – 0.5 ng/ml, the determination limits are 1 ng/ml for aqueous standard solutions. The determinable content of QAC in food products ranges within 1 – 100 ng/g. The results of analysis revealed the residual amount of QAC present in all samples, which confirms data of numerous sources of information about active use of QAC-based disinfectants in the meat and dairy industry. The correctness of the obtained results is verified by introduction of the additives in food products at a level of 10 ng/g for each QAC. The relative standard deviation of the analysis results does not exceed 0.18. The duration of the analysis is 30 – 40 min.

Modern devices for treatment of the surgeon’s hands and the surgical field (literature review)

2020 ◽  
pp. 41-50
Author(s):  
Artem Mikhailovich Morozov ◽  
◽  
Alexey Nikolaevich Sergeev ◽  
Gennady Alexandrovich Dubatolov ◽  
Nikolay Alexandrovich Sergeev ◽  
...  
Keyword(s):  
Cost Effective ◽  
Surgical Infection ◽  
Operating Field ◽  
Functional Additives ◽  
Literary Sources ◽  
Film Forming ◽  
Key Points ◽  
Surgical Field ◽  
Ammonium Compounds ◽  
Active Substances

The aim – analyze modern Russian and foreign literary sources in order to determine modern means for treating the hands of the surgeon and the operating field. Results. One of the key points in the prevention of surgical infection is the treatment of the surgeon’s hands and the operating field with effective skin antiseptics in order to destroy pathogenic and opportunistic microorganisms that colonize intact skin. In modern practice, skin antiseptics are predominantly used containing alcohols as active substances, in particular ethyl, propyl and isopropyl, halogenated substances such as iodine and iodophores, guanidines, which include chlorhexidine digluconate, as well as quaternary ammonium compounds. Moreover, the most widespread are combined preparations containing several active substances and functional additives, which makes it possible to neutralize the negative properties of various active substances. Also, an interesting and promising direction is the use of polymer operating films or film-forming antiseptics. Currently, research is being actively carried out aimed at finding and developing modern highly effective antiseptic agents and their rational combinations that meet the necessary requirements, are optimal in their properties, cost-effective and comfortable to use.

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