Simple Apparatus for Adding Small Amounts of Powder Materials under an Inert Atmosphere

Synlett ◽  
2019 ◽  
Vol 30 (18) ◽  
pp. 2058-2061
Author(s):  
Milandip Karak ◽  
Yohei Joh ◽  
Khamid U. Khodjaniyazov ◽  
Shamansur S. Sagdullaev ◽  
Tohru Oishi ◽  
...  
Keyword(s):  
Inert Atmosphere ◽  
Powder Materials ◽  
Solid Materials ◽  
One Pot ◽  
Simple Apparatus ◽  
Direct Addition ◽  
Dry Conditions ◽  
Powder Addition ◽  
Small Apparatus ◽  
Reproducible Manner

Addition of reactants under an inert atmosphere is a fundamental but extremely important technique in synthetic chemistry. Although this is achievable in many cases by using a glove box or a Schlenk-and-syringe technique, the direct addition of powder (solid) materials without contamination by air or moisture has been difficult, especially in the later stages of a reaction. Here, we offer a simple and small apparatus to realize powder addition with easy handling. Use of this apparatus permitted one-pot glycosylation reactions that required extremely dry conditions to be performed in a highly reproducible manner.

scholarly journals Using of Technogenic Raw Materials Based on Titanium-containing Slag and Aluminum Bronze for the Development of Composite Material

2020 ◽  
Author(s):  
Mikhail Nikolaevich Zakharov ◽  
Nina Iosifovna Ilinykh ◽  
Olga Vladimirovna Romanova ◽  
Olga Fedorovna Rybalko
Keyword(s):  
Composite Material ◽  
Raw Materials ◽  
Thermodynamic Simulation ◽  
Inert Atmosphere ◽  
Powder Materials ◽  
Aluminum Bronze ◽  
X Ray ◽  
Large Particles ◽  
Technogenic Raw Materials ◽  
Pressing Powder

In this study, the possibility of using of the following technogenic raw materials to obtain a composite material was considered: titanium-containing slag, with the addition of aluminum bronze grade PG-19M-01 (TU 48-4206-156-82) and aluminum powder grade PA-4 (GOST 6058-73). The percentage of components in the mixture were as follows (wt. %): slag - 40, PG-19M-01 - 30, PA-4 - 30. A thermodynamic simulation of the selected system was preliminarily carried out using TERRA program in the temperature range 273 - 4273 K. The chemical and granulometric composition of the initial powders was investigated. From the powder mixture there were compressed the tablets and then they were sintered in an inert atmosphere. Micro-X-ray analysis of sintered samples showed that they consist of large particles of various shapes, most likely containing titanium and iron aluminides, their compounds between themselves and with copper. Keywords: titanium-containing slag, composite material, thermodynamic modeling, intermetallic compounds, pressing, powder materials

Copper-Catalyzed Tandem Multi-Component Approach to 1,3-Oxazines at Room Temperature by Cross-Dehydrogenative Coupling Using Methanol as C1 Feedstock

Synlett ◽  
2018 ◽  
Vol 29 (09) ◽  
pp. 1171-1175 ◽  
Author(s):  
Paran Borpatra ◽  
Mohit Deb ◽  
Pranjal Baruah
Keyword(s):  
Carbon Source ◽  
Room Temperature ◽  
Inert Atmosphere ◽  
Environmentally Benign ◽  
Metal Catalyst ◽  
Methylene Carbon ◽  
One Pot ◽  
Dehydrogenative Coupling ◽  
Tert Butyl Hydroperoxide ◽  
Component Approach

A copper(II)-catalyzed multi-component one-pot approach for the synthesis of 1,3-oxazines at room temperature is reported here. Methanol is used as the solvent as well as the carbon source. The methylene carbon of the oxazine product comes from methanol via formaldehyde. tert-Butyl hydroperoxide is used as the oxidant. The reaction uses an environmentally benign metal catalyst and oxidant. No inert atmosphere or precaution is required for the reaction. Most importantly, the reaction avoids the use of carcinogenic formaldehyde.

scholarly journals Effective immobilisation of a metathesis catalyst bearing an ammonium-tagged NHC ligand on various solid supports

2016 ◽  
Vol 12 ◽  
pp. 5-15 ◽  
Author(s):  
Krzysztof Skowerski ◽  
Jacek Białecki ◽  
Stefan J Czarnocki ◽  
Karolina Żukowska ◽  
Karol Grela
Keyword(s):  
Double Bond ◽  
Filter Paper ◽  
Ruthenium Complex ◽  
High Yield ◽  
Subsequent Reduction ◽  
Solid Supports ◽  
Solid Materials ◽  
One Pot ◽  
Metathesis Catalyst ◽  
Palladium On Carbon

An ammonium-tagged ruthenium complex, 8, was deposited on several widely available commercial solid materials such as silica gel, alumina, cotton, filter paper, iron powder or palladium on carbon. The resulting catalysts were tested in toluene or ethyl acetate, and found to afford metathesis products in high yield and with extremely low ruthenium contamination. Depending on the support used, immobilised catalyst 8 shows also additional traits, such as the possibility of being magnetically separated or the use for metathesis and subsequent reduction of the obtained double bond in one pot.

Synthetic Versatility of Lipases: Application for Si–O Bond Formation and Cleavage

Synthesis ◽  
2018 ◽  
Vol 51 (02) ◽  
pp. 477-485 ◽  
Author(s):  
Patrícia Brondani ◽  
Mateus Mittersteiner ◽  
Morgana Voigt ◽  
Bruna Klinkowski ◽  
Dilamara Riva Scharf ◽  
...  
Keyword(s):  
Room Temperature ◽  
Bond Formation ◽  
Inert Atmosphere ◽  
Protecting Groups ◽  
Silyl Ether ◽  
Secondary Alcohols ◽  
Protecting Group ◽  
Silyl Ethers ◽  
Dry Conditions ◽  
Silicon Based

Several commercially available lipases were examined in a study on O–Si bond formation and cleavage applying silicon-based protecting groups and alcohols or the corresponding silyl ethers. With regard to deprotection, from silyl ether to the corresponding alcohol, only the solvent and the lipase were necessary. The influence of the protecting group, the lipase source, and the substituent was investigated to optimize the results. The TMS moiety could be removed in 24 hours of reaction at room temperature in aqueous systems (conv. up to 99%, depending on the substrate and lipase). The reverse reactions, that is, with the protection of the alcohols, were carried out in hexane using different silyl chlorides. The TMS, TES, and TBS moieties were successfully inserted in the primary and secondary alcohols without the need for dry conditions or an inert atmosphere, presenting conversions of up to 99%, depending on the substrate.

Prealloyed Cu-Fe Powder Materials

2007 ◽  
Vol 539-543 ◽  
pp. 2669-2674 ◽  
Author(s):  
Núria Llorca-Isern ◽  
I. Laborde ◽  
X. Mirabet ◽  
P. Molera ◽  
Antoni Roca
Keyword(s):  
Plastic Deformation ◽  
Mechanical Alloying ◽  
Aggregate Size ◽  
Inert Atmosphere ◽  
Powder Materials ◽  
Materials Selection ◽  
Microscopic Scale ◽  
Hard Materials ◽  
Deformation Processes ◽  
Selection For

Mechanical alloying (MA) is one of the most appropriate severe plastic deformation processes applied to powders in order to obtain good mixing, new different systems or alloys and / or to reduce particles grain size from the starting powders. In the present work, MA was used to obtain prealloyed powders of Cu-Fe base alloys suitable for subsequent sintering. Mechanical alloying process parameters have been optimised to reduce container and balls contamination in dry and inert atmosphere conditions. For safe final powder manipulation, the final aggregate size requirement needed to be kept in the microscopic scale. The microstructural results showed that the components of the original powders were intimately combined resulting in alloyed aggregates suitable for sintering and for mixing to other hard materials to obtain composites. The materials selection for container and balls is critical in order to avoid contamination. In the present work, no contamination was detected in the final processed particles. Consolidation of these powders was carried out as well as calorimetric tests for studying their stability.

One Pot, Environmentally Benign, Thermal Reaction to Fabricate WSe2 and MoSe2 Nanoplates

2008 ◽  
Vol 3 ◽  
pp. 15-24 ◽  
Author(s):  
Vilas Ganpat Pol ◽  
Swati Vilas Pol ◽  
Aharon Gedanken
Keyword(s):  
Sandwich Structure ◽  
Inert Atmosphere ◽  
Thermal Reaction ◽  
Single Step ◽  
Environmentally Benign ◽  
Metal Particles ◽  
One Pot ◽  
Boiling Points ◽  
Very High ◽  
Closed Reactor

The two dimensional nanoplates of WSe2 and MoSe2 are the result of solid-state thermal (750oC) reaction between micrometer-sized W or Mo with micro-size Se powder under inert atmosphere via carving phenomena in a closed reactor. This is a distinct top-down approach presented for the fabrication of inorganic nanoplates, where micron-sized metal particles having very high melting and boiling points are converted into a Se–M–Se sandwich structure employing a single-step, scalable, and environmentally- friendly chemical reaction under autogenic pressure at elevated temperature (RAPET). The mechanistic elucidation of the creation of WSe2/MoSe2 nanoplates is suggested on the basis of the crystal structure with the support of data obtained from compositional, structural, and morphological characterizations.

scholarly journals Using silver nanoparticles for the increase of YAG: Ce luminescence

2021 ◽  
Vol 2094 (2) ◽  
pp. 022021
Author(s):  
A A Kravtsov ◽  
I S Chikulina ◽  
S N Kichuk ◽  
V A Tarala ◽  
M S Nikova ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Luminescence Intensity ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Reference Sample ◽  
Average Diameter ◽  
Inert Atmosphere ◽  
Chemical Reduction Method ◽  
Two Stage ◽  
Direct Addition

Abstract In this study, silver nanoparticles with an average diameter of 50-70 nm were synthesized by the chemical reduction method. Subsequently, nanoparticles in different concentrations were introduced into the YAG: Ce luminescent powder synthesized by the method of two-stage coprecipitation into hexamine. The luminescence of samples with different contents of nanosilver was investigated. It was shown that the direct addition of nanosilver to YAG: Ce significantly impairs luminescence. Upon calcination at 900 °C, an increase in the luminescence of the YAG: Ce samples with silver nanoparticles was observed; however, the luminescence intensity was lower than that of the reference sample (without nanosilver). After calcination in an inert atmosphere at a temperature of 1550 °C, a significant increase in the luminescence intensity (of the order of 30-40 %) of the samples with the addition of a nanosilver was observed in comparison with the reference sample. Thus, silver nanoparticles can be successfully used to improve the YAG: Ce phosphors.

A facile self-template and carbonization strategy to fabricate nickel nanoparticle supporting N-doped carbon microtubes

2018 ◽  
Vol 5 (4) ◽  
pp. 844-852 ◽  
Author(s):  
Jianping Wang ◽  
Min Zhang ◽  
Teng Miao ◽  
Yang Ling ◽  
Qiong Wen ◽  
...  
Keyword(s):  
Inert Atmosphere ◽  
One Pot ◽  
Nickel Ion ◽  
Thin Coatings ◽  
Nickel Nanoparticle

A facile one-pot approach is utilized to construct nickel-ion–PDA complex thin coatings on MoO3@PPy microtubes, which can be carbonized under an inert atmosphere to obtain nickel/N-doped carbon microtubes (Ni/NCMTs).

Iron-Containing Yttria-Stabilized Zirconia System For Two-Step Thermochemical Water Splitting

2007 ◽  
Vol 130 (1) ◽  
Author(s):  
Nobuyuki Gokon ◽  
Takayuki Mizuno ◽  
Yumiko Nakamuro ◽  
Tatsuya Kodama
Keyword(s):  
Water Splitting ◽  
Thermal Reduction ◽  
Inert Atmosphere ◽  
Yttria Stabilized Zirconia ◽  
Temperature Reaction ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
Solid Materials ◽  
X Ray ◽  
High Temperature Reaction

An iron-containing yttria-stabilized zirconia (YSZ) or Fe-YSZ was found to be a promising working redox material for the thermochemical two-step water-splitting cycle. The Fe-YSZ was formed by a high-temperature reaction between YSZ doped with more than 8mol%Y2O3 and Fe3O4 supported on the YSZ at 1400°C in an inert atmosphere. The formed Fe-YSZ reacted with steam to generate hydrogen at 1000°C. The oxidized Fe-YSZ was reactivated by a thermal reduction at 1400°C in an inert atmosphere. The alternative O2 and H2 generations in the repeated two-step reactions and the X-ray diffraction and chemical analysis studies on the solid materials indicated that the two-step water splitting was associated with a redox transition between Fe2+–Fe3+ ions in the cubic YSZ lattice.

Optical and cytotoxicity properties of water soluble type II CdTe/CdSe nanoparticles synthesised via a green method

2015 ◽  
Vol 1748 ◽  
Author(s):  
Vuyelwa Ncapayi ◽  
Samuel O. Oluwafemi ◽  
Sandile P. Songca ◽  
Tetsuya Kodama
Keyword(s):  
Reaction Time ◽  
Inert Atmosphere ◽  
Stability Study ◽  
Water Soluble ◽  
Shell Nanoparticles ◽  
One Pot ◽  
Absorption And Emission ◽  
Aging Period ◽  
Cdse Layer ◽  
The Stability

ABSTRACTWe herein report the optical and cytotoxicity properties of highly luminescent water soluble mercaptopropanoic acid (MPA) capped CdTe/CdSe core shell nanoparticles (NPs). The synthesis of the CdTe/CdSe NPs was carried out via a simple, one pot and economical route, involving the use of greener materials under ambient environment in the absence of an inert atmosphere. The temporal evolution of the size and optical properties of the nanomaterials was investigated by varying the reaction time and stability of the as-synthesised material at pH 12. The as-synthesised nanomaterials were characterised using UV-vis absorption and photoluminescence (PL) spectroscopy. The nanoparticles obtained were of high quality with high absorption and emission features. Addition of Se precursor to produce CdSe layer on the CdTe NPs core surface resulted in significant red shirt of both the absorption and emission maxima. The stability study showed that the emission maximum peak positions and FWHM remain the same with increase in emission intensity for all the NPs during the aging period. The cytotoxicity assay showed very high cell viability for the CdTe/CdSe NPs produced at 7 h compared with those produced at 30 mins as the concentration increased from 0.1 to 60 ug/ml. The lower cytotoxicity at the higher reaction time was attributed to the higher stability of the material and hence lower release of Cd2+.

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