scholarly journals Молекулярные магнетики --- источники радиочастотного сверхизлучения при механической активации

2021 ◽  
Vol 47 (1) ◽  
pp. 23
Author(s):  
А.И. Александров ◽  
В.Г. Шевченко ◽  
И.А. Александров ◽  
С.В. Фокин ◽  
В.И. Овчаренко
Keyword(s):  
Radio Frequency ◽  
Mechanical Activation ◽  
Molecular Magnet ◽  
Rheological Explosion ◽  
Polystyrene Matrix ◽  
First Time

The effect of mechanical activation of radio frequency superradiance in a composite based on a heterospin molecular magnet and a polystyrene matrix has been established. Mechanical activation was carried out for the first time in unloading mode of rheological explosion .

scholarly journals Генерация сверхизлучения импульсным механическим воздействием

2020 ◽  
Vol 46 (7) ◽  
pp. 43
Author(s):  
А.И. Александров ◽  
В.Г. Шевченко ◽  
И.А. Александров
Keyword(s):  
High Pressure ◽  
Radio Frequency ◽  
Mechanical Activation ◽  
Mechanical Action ◽  
Binuclear Complexes ◽  
Processing Data ◽  
Rheological Explosion ◽  
Polystyrene Matrix

The effect of pulsed mechanical activation of radio-frequency superradiation in the parametric mode is established: when an external rheological explosion under high pressure acts on a paramagnetic composite --- a system of crossed spins based on binuclear complexes Co (QH) _2-O-Co (QH) 2 or Mn (QH) _2-O-Mn (QH) 2 (QH --- ligand based on 3,6-di-tert-butylpyrocatechol) in a polystyrene matrix. A possible method for processing data on pulsed mechanical action and a possible explanation of the effect are proposed.

scholarly journals Сверхизлучение и синтез наночастиц металла в полистирольном композите с многоспиновыми комплексами Eu при быстром одноосном сдавливании

2022 ◽  
Vol 92 (2) ◽  
pp. 258
Author(s):  
А.И. Александров ◽  
В.Г. Шевченко ◽  
С.С. Абрамчук ◽  
С.Б. Зезин ◽  
С.В. Фокин ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Mechanical Activation ◽  
Metal Nanoparticles ◽  
Radical Anion ◽  
Molecular Magnet ◽  
Paramagnetic Centers ◽  
Free Electrons ◽  
Tert Butyl

Composites of heterospin molecular magnet [EuIII(SQ)3bipy] in a polystyrene (PS) matrix have been synthesized. This complex [EuIII(SQ)3bipy] contains four paramagnetic centers - the Eu3+ ion and three SQ ligands (SQ—3,6-di-tert-butyl benzoquinone radical anion); bipy (bipyridyl) is diamagnetic. It has been established that intensive mechanical activation of [EuIII(SQ)3bipy]/PS samples leads to an reological explosion, as a result of which radio frequency superradiance, the appearance of free electrons and the formation of Eu metal nanoparticles are observed. The duration of this process is 10 ns.

scholarly journals Heating of Ti3C2Tx MXene/polymer composites in response to Radio Frequency fields

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Touseef Habib ◽  
Nutan Patil ◽  
Xiaofei Zhao ◽  
Evan Prehn ◽  
Muhammad Anas ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Thermal Imaging ◽  
Electromagnetic Waves ◽  
Rapid Heating ◽  
Composite Films ◽  
Heating Rates ◽  
New Material ◽  
High Dielectric ◽  
First Time ◽  
Percolating Network

Abstract Here we report for the first time that Ti3C2Tx/polymer composite films rapidly heat when exposed to low-power radio frequency fields. Ti3C2Tx MXenes possess a high dielectric loss tangent, which is correlated with this rapid heating under electromagnetic fields. Thermal imaging confirms that these structures are capable of extraordinary heating rates (as high as 303 K/s) that are frequency- and concentration-dependent. At high loading (and high conductivity), Ti3C2Tx MXene composites do not heat under RF fields due to reflection of electromagnetic waves, whereas composites with low conductivity do not heat due to the lack of an electrical percolating network. Composites with an intermediate loading and a conductivity between 10–1000 S m−1 rapidly generate heat under RF fields. This finding unlocks a new property of Ti3C2Tx MXenes and a new material for potential RF-based applications.

Radio-frequency superradiance induced by the rheological explosion of polymer composites containing paramagnetic cobalt complexes

2016 ◽  
Vol 10 (1) ◽  
pp. 69-76 ◽  
Author(s):  
A. I. Aleksandrov ◽  
I. A. Aleksandrov ◽  
S. B. Zezin ◽  
E. N. Degtyarev ◽  
A. A. Dubinskiy ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Polymer Composites ◽  
Cobalt Complexes ◽  
Rheological Explosion

scholarly journals Radio-Frequency-Based NH3-Selective Catalytic Reduction Catalyst Control: Studies on Temperature Dependency and Humidity Influences

Sensors ◽  
2017 ◽  
Vol 17 (7) ◽  
pp. 1615 ◽  
Author(s):  
Markus Dietrich ◽  
Gunter Hagen ◽  
Willibald Reitmeier ◽  
Katharina Burger ◽  
Markus Hien ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Selective Catalytic Reduction ◽  
New Technologies ◽  
Catalytic Reduction ◽  
Special Focus ◽  
Temperature Range ◽  
Scr Catalysts ◽  
Rf Signals ◽  
High Space ◽  
First Time

The upcoming more stringent automotive emission legislations and current developments have promoted new technologies for more precise and reliable catalyst control. For this purpose, radio-frequency-based (RF) catalyst state determination offers the only approach for directly measuring the NH3 loading on selective catalytic reduction (SCR) catalysts and the state of other catalysts and filter systems. Recently, the ability of this technique to directly control the urea dosing on a current NH3 storing zeolite catalyst has been demonstrated on an engine dynamometer for the first time and this paper continues that work. Therefore, a well-known serial-type and zeolite-based SCR catalyst (Cu-SSZ-13) was investigated under deliberately chosen high space velocities. At first, the full functionality of the RF system with Cu-SSZ-13 as sample was tested successfully. By direct RF-based NH3 storage control, the influence of the storage degree on the catalyst performance, i.e., on NOx conversion and NH3 slip, was investigated in a temperature range between 250 and 400 °C. For each operation point, an ideal and a critical NH3 storage degree was found and analyzed in the whole temperature range. Based on the data of all experimental runs, temperature dependent calibration functions were developed as a basis for upcoming tests under transient conditions. Additionally, the influence of exhaust humidity was observed with special focus on cold start water and its effects to the RF signals.

Effect of mechanically activated raw materials on β-sialon formation by combustion synthesis

2007 ◽  
Vol 22 (10) ◽  
pp. 2863-2867 ◽  
Author(s):  
Ramasamy Sivakumar ◽  
Kazuhiko Aoyagi ◽  
Tomohiro Akiyama
Keyword(s):  
Mechanical Activation ◽  
Combustion Synthesis ◽  
Milling Time ◽  
Raw Materials ◽  
Raw Material ◽  
First Time

The influence of different raw material mixtures on β-sialon (Si6−zAlzOzN8−z, 1 ⩽ z ⩽ 4) formation through mechanical activation coupled combustion synthesis (MA-CS) was investigated in low nitriding atmosphere of 1 MPa without diluent inclusions. The MA-CS performed for the first time on sialon raw materials with milling time of 18 min obtained sialons more than three times as pure as those obtained by CS of mixtures ball milled to 1 h (z = 3). The starting materials containing silicon, aluminum, and alumina (z = 4) after MA-CS had an increment of sialon amounts up to 88 mass%.

scholarly journals Iron(IV) Complexes with Tetraazaadamantane-based Ligands: Synthesis, Structure, Application in Dioxygen Activation and Labeling of Biomolecules

2021 ◽  
Author(s):  
Ivan Golovanov ◽  
Anton Leonov ◽  
Vladislav Lesnikov ◽  
Evgeny Pospelov ◽  
Kirill Frolov ◽  
...  
Keyword(s):  
Aerobic Oxidation ◽  
Dioxygen Activation ◽  
Excellent Performance ◽  
Cage Structure ◽  
X Ray ◽  
Polystyrene Matrix ◽  
Oxidase Enzyme ◽  
Ft Ir ◽  
Thiol Oxidase ◽  
First Time

4,6,10-Trihydroxy-1,4,6,10-tetraazaadamantane (TAAD) has been shown to form a stable Fe(IV) complex having a diamantane cage structure, in which the metal center is coordinated by three oxygen atoms of the deprotonated ligand. The complex was characterized by X-ray, HRMS, NMR, FT-IR, Mössbauer spectroscopy and DFT calculations, which supported d4 configuration of iron. The Fe(IV)-TAAD complex showed excellent performance in dioxygen activation under mild conditions serving as a mimetic of the thiol oxidase enzyme. The nucleophilicity of the bridge-head nitrogen atom in TAAD provides a straightforward way for conjugation of Fe(IV)-TAAD complexes to various functional molecules. Using this approach, steroidal and peptide molecules having an iron(IV) label have been prepared for the first time. Also, the Fe(IV)-TAAD complex was covalently bounded to a polystyrene matrix and the resulting material was shown to serve as a heterogeneous catalyst for aerobic oxidation of thiols to disulfides.

Synergism of mechanical activation and sulfurization to recover copper from waste printed circuit boards

RSC Advances ◽  
2014 ◽  
Vol 4 (94) ◽  
pp. 51970-51976 ◽  
Author(s):  
Zhiyuan Ou ◽  
Jinhui Li
Keyword(s):  
Free Radical ◽  
Mechanical Activation ◽  
Printed Circuit Boards ◽  
Circuit Boards ◽  
Free Radical Theory ◽  
Radical Theory ◽  
Printed Circuit ◽  
Waste Printed Circuit Boards ◽  
First Time

This work proposed a synergistic route of mechanic activation and sulfurization to recover copper from waste printed circuit boards for the first time and take successful use of free radical theory in assessing the synergism mechanism.

scholarly journals Schwannoma of the posterior pharyngeal wall in a child

2021 ◽  
Author(s):  
Peng Zhu ◽  
Xiao Yan Li
Keyword(s):  
Radio Frequency ◽  
Rare Case ◽  
Posterior Pharyngeal Wall ◽  
Pharyngeal Wall ◽  
First Case ◽  
Severe Difficulty ◽  
First Time

Abstract Background: To our knowledge, There are only 7 cases of posterior pharyngeal wall schwannoma which have been previously reported in the literature, but none of them was associated with a 3-year-old child.Case presentation: We presented a rare case of a schwannoma which is localized on the posterior pharyngeal wall, It caused severe difficulty in swallowing and breathing in a child whose age is three years old. Schwannomas of the posterior pharyngeal wall has been rarely reported in children, The tumor was removed with plasma radio frequency excision via a transoral route, There was not seen any recurrence of tumor by examination of CT or MRI up to two years. as far as we know, It's the first time which a case of posterior pharyngeal wall schwannoma that has been reported to occur in a 3-year-old child, and the first case in which the schwannoma was removed via transoral plasma radio frequency excision.Conclusions: This case illustrates that schwannoma may be found in children ,and it is safe to treat this disease through plasma radio frequency excision via a transoral route.

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