scholarly journals The catalytic activity of copper nanoparticles on aminomodified silica support in the flow azide-alkyne cycloaddition reaction using macrocyclic substrates

2019 ◽  
Vol 57 (2) ◽  
pp. 1-9
Author(s):  
Albina T. Nurmukhametova ◽  
◽  
Roman N. Belov ◽  
Vladimir A. Burilov ◽  
Igor S. Antipin ◽  
...  
Keyword(s):  
Copper Nanoparticles ◽  
Inductively Coupled Plasma ◽  
Chemical Reduction ◽  
Cycloaddition Reaction ◽  
Nitrogen Adsorption ◽  
Propargyl Alcohol ◽  
Hydroxyl Group ◽  
Aryl Azides ◽  
Consecutive Reaction ◽  
Inductively Coupled

Using the chemical reduction method, a copper-containing catalyst on an amino-modified silica was obtained. The structure and composition of the catalyst were characterized by low-temperature nitrogen adsorption and inductively coupled plasma mass spectrometry. It was found that the modification of silica with amino groups and copper nanoparticles leads to a significant change in textural characteristics: nanoparticles and the modifier fill the pores in the size range of 5-10 nm. Obtained catalyst showed good activity in the flow cycloaddition of azides and alkynes of various nature. The comparative activity of azides and alkynes was analyzed. It has been established that among the azides studied (benzyl azide, p-nitrobenzylazide, p-methoxybenzylazide, 2-azidoethylacetate and 1-azidodecane), alkyl and aryl azides with electron-withdrawing groups were most active due to an increase in the electrophilicity of the terminal nitrogen atom of the azide group. Among the studied acetylenes (phenylacetylene, hexin-1, trimethylsilylacetylene and propargyl alcohol), propargyl alcohol was the most and trimethylsilylacetylene was the less active. Increased activity of propargyl alcohol may be due to a donor hydroxyl group capable of coordinating with copper; reduced activity of trimethylsilylacetylene can be resulted from steric hindrances. p-tert-Butyl and p-H-calix[4]arens were also used in the reaction. Full conversion of macrocycles was achieved after 3 consecutive reaction cycles. The resulting triazoles were isolated and characterized by a complex of physical methods. Thus, It has been demonstrated that carrying out the reaction in a flow by maintaining stable and fully reproducible reaction parameters makes it possible to quickly evaluate the relative reactivity of molecules.

scholarly journals Migration of Silver and Copper Nanoparticles from Food Coating

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 380
Author(s):  
Hamed Ahari ◽  
Leila Khoshboui Lahijani
Keyword(s):  
Copper Nanoparticles ◽  
Inductively Coupled Plasma ◽  
Food Packaging ◽  
Human Life ◽  
Analytical Techniques ◽  
Optical Emission ◽  
Atomic Emission ◽  
The Body ◽  
Toxic Effects ◽  
Inductively Coupled

Packaging containing nanoparticles (NPs) can increase the shelf life of products, but the presence of NPs may hazards human life. In this regard, there are reports regarding the side effect and cytotoxicity of nanoparticles. The main aim of this research was to study the migration of silver and copper nanoparticles from the packaging to the food matrix as well as the assessment techniques. The diffusion and migration of nanoparticles can be analyzed by analytical techniques including atomic absorption, inductively coupled plasma mass spectrometry, inductively coupled plasma atomic emission, and inductively coupled plasma optical emission spectroscopy, as well as X-ray diffraction, spectroscopy, migration, and titration. Inductively coupled plasma-based techniques demonstrated the best results. Reports indicated that studies on the migration of Ag/Cu nanoparticles do not agree with each other, but almost all studies agree that the migration of these nanoparticles is higher in acidic environments. There are widespread ambiguities about the mechanism of nanoparticle toxicity, so understanding these nanoparticles and their toxic effects are essential. Nanomaterials that enter the body in a variety of ways can be distributed throughout the body and damage human cells by altering mitochondrial function, producing reactive oxygen, and increasing membrane permeability, leading to toxic effects and chronic disease. Therefore, more research needs to be done on the development of food packaging coatings with consideration given to the main parameters affecting nanoparticles migration.

scholarly journals A study concerning the pretreatment of CNTs and its influence on the performance of NIB/CNTs amorphous catalyst

2006 ◽  
Vol 71 (11) ◽  
pp. 1153-1160 ◽  
Author(s):  
Chang Hu-Yuan ◽  
Feng Li ◽  
Li. Hua ◽  
Bin Zhang
Keyword(s):  
Selective Hydrogenation ◽  
Inductively Coupled Plasma ◽  
Acid Treatment ◽  
Chemical Reduction ◽  
X Ray Diffraction ◽  
Chemical Reduction Method ◽  
X Ray ◽  
Inductively Coupled ◽  
Selective Hydrogenation Of Acetylene ◽  
Transmission Electron

As prepared carbon nanotubes were pretreated with nitric acid (CNTs-HNO3) or ammonia (CNTs-NH3). Fourier transform infrared spectroscopy (FTIR) measurements showed that the surface of the nanotubes was functionalized with carboxylic and hydroxyl functional groups after the acid treatment and that basic groups containing nitrogen, such as N-H and C-N, were introduced to the surface of the nanotubes after the ammonia treatment. X-Ray diffraction analysis implied that the nickel residue in the CNTs was effectively removed by acid treatment. However, the nickel residue was only partially eliminated by ammonia pretreatment. NiB amorphous catalysts supported on CNTs-HNO3 and CNTs-NH3 were prepared by the impregnation-chemical reduction method and characterized by transmission electron microscopy (TEM), as well as inductively coupled plasma (ICP) spectroscopy and studied in the selective hydrogenation of acetylene. TEM measurements showed that a high density NiB particles of about 9 nm were homogeneously dispersed on the CNTs-NH3. However, NiB particles (13-23 nm)with amean size of 16 nm were scattered on the CNTs-HNO3.As a result, the activity and selectivity of NiB/CNTs-NH3 were higher than those of NiB/CNTs-HNO3 in the selective hydrogenation of acetylene.

Preparation and Characterization of Sg. Sayong Clay Material for Biocatalyst Immobilization

2013 ◽  
Vol 737 ◽  
pp. 145-152 ◽  
Author(s):  
Nurul Aini Edama ◽  
Alawi Sulaiman ◽  
Ku Halim Ku Hamid ◽  
Miradatul Najwa Mohd Rodhi ◽  
Mohibbah Musa ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Nitrogen Adsorption ◽  
Atomic Emission ◽  
Wire Mesh ◽  
Emission Spectrometry ◽  
Clay Material ◽  
Plasma Atomic Emission Spectrometry ◽  
X Ray ◽  
Inductively Coupled ◽  
Supporting Material

This study was conducted to characterize Sg. Sayong clay so that it can be applied as a supporting material for the immobilization of biocatalyst in the bioconversion of wastewater into biofuel. The clay sample was physically and chemically characterized using Nitrogen Adsorption, X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) and Field Emission Scanning Electron Microscopy (FESEM). The results obtained showed that the clay composed of SiO2 (57.4%), followed by Al2O3 (32.5%), K2O (4.9%), Fe2O3 (3.8%) and traces amount of Ca, Mg, Ma, and Ti. The results also showed the clay type was kaolinite with some presence of quartz, illite, montmorillonite and microcline. The clay was also successfully coated onto the wire-mesh and immobilized with biocatalyst for further bioconversion study.

A pre-column derivatization method allowing quantitative metabolite profiling of carboxyl and phenolic hydroxyl group containing pharmaceuticals in human plasma via liquid chromatography-inductively coupled plasma-tandem mass spectrometry (LC-ICP-MS/MS)

2018 ◽  
Vol 33 (2) ◽  
pp. 274-282 ◽  
Author(s):  
Sanwang Li ◽  
Balázs Klencsár ◽  
Lieve Balcaen ◽  
Filip Cuyckens ◽  
Frederic Lynen ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Inductively Coupled Plasma ◽  
Metabolite Profiling ◽  
Hydroxyl Group ◽  
Tandem Mass ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Analytical Strategies

Novel analytical strategies for investigating drug ADME (absorption, distribution, metabolism and excretion).

Silver Ion Modified Anionic Surfactant Templated Mesoporous Silica Adsorption Materials for the Removal of Dimethyl Sulfide at Ambient Temperature

2012 ◽  
Vol 512-515 ◽  
pp. 2412-2418
Author(s):  
Xiao Dan Zhang ◽  
Zhui Hui Hu ◽  
Dong Hui Zhang
Keyword(s):  
Mesoporous Silica ◽  
Inductively Coupled Plasma ◽  
Dimethyl Sulfide ◽  
Optical Emission ◽  
Nitrogen Adsorption ◽  
Silver Ion ◽  
Emission Spectrometry ◽  
Ambient Temperatures ◽  
Inductively Coupled ◽  
Adsorption Desorption

Silver ion modified mesoporous silica (Ag-AMS-2) was prepared by using N-lauroyl-L-glutamic acid as structure directing agents and applied to dimethly sulfide (DMS) removal at ambient temperatures. The silver ion interacted with the amino group through coordination bonds and then the silver ion were as the adsorptive sites of the DMS. These Ag-AMS-2 materials were characterized by X-ray diffraction (XRD), nitrogen adsorption desorption, high-resolution transmission electron microscopy (HRTEM), thermal analysis and inductively coupled plasma optical emission spectrometry (ICP-OES). The performance of these Ag-AMS-2 materials as DMS adsorbents was tested using a dynamic breakthrough test. And these samples showed high removal efficiency and high saturation adsorption capacity of DMS.

Friedel-Crafts alkylation of benzene with benzyl alcohol over H-MCM-22

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Deniz Karabulut ◽  
Sema Akyalcin
Keyword(s):  
Benzyl Alcohol ◽  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Hydrothermal Condition ◽  
Nitrogen Adsorption ◽  
Product Distribution ◽  
Emission Spectrometry ◽  
Inductively Coupled ◽  
Alkylation Of Benzene ◽  
Temperature Programmed

Abstract MCM-22 was synthesized by using silicic acid powder as a silica source under the static hydrothermal condition and characterized by X-ray diffraction, nitrogen adsorption-desorption isotherms, scanning electron microscopy, inductively coupled plasma optical emission spectrometry, and temperature-programmed desorption of ammonia. The liquid phase benzylation of benzene with benzyl alcohol to diphenylmethane was investigated over H-MCM-22. The effects of reaction parameters on the conversion of benzyl alcohol and product distribution were determined. Under optimal reaction conditions, diphenylmethane yield of 92.1% was achieved for 99.3% conversion of benzyl alcohol in 3 h of reaction period. The reusability of the catalyst was also investigated after calcination of the catalyst in stagnant air at 500 °C for 4 h. The results show that the organic species produced during the reaction deposited in the catalyst lead to the deactivation of the catalyst and the calcination of the deactivated catalyst causes catalyst dealumination.

scholarly journals The Development of Metal-Carbon Catalysts for Oxidative Desulfurization of Diesel Fractions

2020 ◽  
Vol 22 (2) ◽  
pp. 81
Author(s):  
Z.R. Ismagilov ◽  
E.V. Matus ◽  
O.S. Efimova ◽  
L.M. Khitsova ◽  
A.N. Popova ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Inductively Coupled Plasma ◽  
Oxidative Desulfurization ◽  
Optical Emission ◽  
Nitrogen Adsorption ◽  
Physicochemical Characteristics ◽  
Emission Spectrometry ◽  
Incipient Wetness Impregnation ◽  
Inductively Coupled ◽  
Carbon Catalysts

Metal-carbon materials M/CNTs (M = Ce, Сu, Mo) were synthesized by incipient wetness impregnation and their physicochemical characteristics were studied using various methods (inductively coupled plasma optical emission spectrometry, thermal analysis coupled with mass spectrometry, low-temperature nitrogen adsorption, X-ray diffraction and structural analysis, scanning electron microscopy, and Raman spectroscopy). It was found that M/CNTs (M = Ce, Сu, Mo) are the mesoporous materials consisting of carbon nanotubes with deposited СeO2, Сu2O/Cu or МоО3/MoO2 particles, respectively. The dispersion of supported species and their deposition uniformity improve in the series Сu < Се < Мо. The type of metal was shown to affect thermal stability as well as the textural and structural properties of the samples. The thermal stability of materials increases in the series Ce < Cu ≈ Mo, which is caused by different redox properties of the metals and also by the composition of products of the metal precursor decomposition. It is promising to use the developed materials as the catalysts for deep purification of diesel fraction components from sulfur compounds.

Preparation of Nanosized RuB with Lower Ru Content Supported on Al2O3 and its Catalytic Activity

2012 ◽  
Vol 557-559 ◽  
pp. 1467-1470
Author(s):  
Sheng Xian Xu ◽  
Feng Yi Li
Keyword(s):  
Catalytic Activity ◽  
Amorphous Alloy ◽  
Inductively Coupled Plasma ◽  
Chemical Reduction ◽  
Benzene Hydrogenation ◽  
Transmission Electron Micrograph ◽  
X Ray Diffraction ◽  
Inductively Coupled ◽  
Transmission Electron ◽  
Loading Amount

The nanosized RuB amorphous alloys with three different ruthenium contents supported on Al2O3 were prepared by means of impregnation, following the chemical reduction with KBH4 solution. The gas-phase benzene hydrogenation was used as a probe reaction to evaluate the catalytic activity of the prepared catalysts. The catalysts were characterized by BET, inductively coupled plasma (ICP), X-ray diffraction (XRD), and transmission electron micrograph (TEM). The experiment results show that the catalytic activity of the three amorphous alloy catalysts goes up first with the increasing of temperature and has a maximum at 443K; when the Ru loading amount is 0.24 %(wt.%) of the catalyst, which is very few, the conversion of benzene on RuB/Al2O3 amorphous alloy catalyst can reach to 99.50% at 443K.

scholarly journals Integration of Fe in natural and synthetic Al-pyrophyllites: an infrared spectroscopic study

Clay Minerals ◽  
2007 ◽  
Vol 42 (1) ◽  
pp. 129-141 ◽  
Author(s):  
S. Lantenois ◽  
J.-M. Beny ◽  
F. Muller ◽  
R. Champallier
Keyword(s):  
Inductively Coupled Plasma ◽  
Hydroxyl Group ◽  
Chemical Compositions ◽  
Infrared Spectroscopic Study ◽  
X Ray Diffraction ◽  
Inductively Coupled ◽  
Fe Content ◽  
Three Samples ◽  
Band Position ◽  
Natural And Synthetic

AbstractNumerous studies focus on the relationships between chemical composition and OH-band positions in the infrared (IR) spectra of micaceous minerals. These studies are based on the coexistence, in dioctahedral micas or smectites, of several cationic pairs around the hydroxyl group which each produce a characteristic band in the IR spectrum. The aim of this work is to obtain the wavenumber values of the IR OH vibration bands of the (Al-Fe3+)-OH and (Fe3+-Fe3+)-OH local cationic environments of ‘pyrophyllite type’ in order to prove, disprove or modify a model of dioctahedral phyllosilicate OH-stretching band decomposition. Natural samples are characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopies and electron microprobe; the hydrothermal synthesis products are also analysed by powder XRD and FTIR after inductively coupled plasma measurements to obtain the chemical compositions of starting gel phases. Natural samples contain some impurities which were eliminated after acid treatment; nevertheless, a small Fe content is found in the pyrophyllite structure. The amount of Fe which is incorporated within the pyrophyllite structure is much more important for the synthetic samples than for the natural ones. The IR OH bands were clearly observed in both natural and synthetic pyrophyllites and assigned to hydroxides bonded to (Al-Al), (Al-Fe) and (Fe-Fe) cationic pairs. During this study, three samples were analysed by DTG to check the cis- or trans-vacant character of the layers and to determine the influence of this structural character on the OH-stretching band position in IR spectroscopy.

scholarly journals Environmentally benign copper nanoparticles supported on walnut shell as a highly durable nanocatalyst for the synthesis of propargylamines

2017 ◽  
Vol 82 (11) ◽  
pp. 1211-1221 ◽  
Author(s):  
Fariba Saadati ◽  
Vahid Leghaei ◽  
Asghar Zamani
Keyword(s):  
Copper Nanoparticles ◽  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Practical Method ◽  
Catalytic Performance ◽  
Emission Spectrometry ◽  
Walnut Shell ◽  
X Ray ◽  
Inductively Coupled ◽  
Three Component Reaction

This study was an attempt to prepare copper nanoparticles and to determine their catalytic activity employing walnut shell (WS) residue as a green support and a reusable material. The nanocatalyst was characterized though inductively coupled plasma optical emission spectrometry (ICP-OES), N2-sorption analysis, X-ray powder diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). The catalytic performance of CuNPs@WS was then studied in the preparation of propargylamines via a three-component reaction. The catalyst could be recovered and reused without a significant decrease in its activity over eight reaction cycles. The simple methodology described herein is an economic, ecofriendly and practical method accompanied by higher yields.

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