Effect of innovative ultrasonic frequency excitation modes on rice protein: Enzymolysis and structure

Enhancing water purification processes is provided by various methods including physical ones, in particular, exposure to ultrasonic vibrations. The change in the dynamic viscosity of water affects the rate of deposition of particles in the aquatic environment which can be used in natural and wastewater treatment. At the Department Water Supply and Wastewater Disposal of the National Research Moscow State University of Civil Engineering experimental studies were conducted under laboratory conditions to study the effect of ultrasound on the change in the dynamic viscosity of water. A laboratory setup has been designed consisting of an ultrasonic frequency generator of the relative intensity, a transducer (concentrator) that transmits ultrasonic vibrations to the source water, and sonic treatment tanks. Experimental studies on the impact of the ultrasonic field in the cavitation mode on the dynamic viscosity of the aqueous medium were carried out the exposure time was obtained to achieve the maximum effect.Интенсификация процессов очистки воды осуществляется с помощью различных методов, в том числе и физических, в частности воздействием ультразвуковых колебаний. Изменение динамической вязкости воды влияет на скорость осаждения частиц в водной среде, что может быть использовано в процессах очистки природных и сточных вод. На кафедре Водоснабжение и водоотведение Национального исследовательского Московского государственного строительного университета в лабораторных условиях проведены экспериментальные исследования по изучению влияния ультразвука на изменение динамической вязкости воды. Разработана схема лабораторной установки, состоящая из генератора ультразвуковых частот с соответствующей интенсивностью, преобразователя (концентратора), передающего ультразвуковые колебания в исходную воду, и емкости для озвучивания. Выполнены экспериментальные исследования по влиянию ультразвукового поля в режиме кавитации на динамическую вязкость водной среды, получено время экспозиции для достижения максимального эффекта.

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Usability of Ultrasonic Frequency Testing for Rapid Generation of High and Very High Cycle Fatigue Data

Materials ◽

10.3390/ma14092245 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2245

Author(s):

Michael Fitzka ◽

Bernd M. Schönbauer ◽

Robert K. Rhein ◽

Niloofar Sanaei ◽

Shahab Zekriardehani ◽

...

Keyword(s):

Strain Rate ◽

High Cycle Fatigue ◽

Fatigue Properties ◽

Ultrasonic Frequency ◽

Cycle Fatigue ◽

Reinforced Polymer ◽

Very High Cycle Fatigue ◽

Ultrasonic Fatigue ◽

Fibre Reinforced Polymer ◽

Very High

Ultrasonic fatigue testing is an increasingly used method to study the high cycle fatigue (HCF) and very high cycle fatigue (VHCF) properties of materials. Specimens are cycled at an ultrasonic frequency, which leads to a drastic reduction of testing times. This work focused on summarising the current understanding, based on literature data and original work, whether and how fatigue properties measured with ultrasonic and conventional equipment are comparable. Aluminium alloys are not strain-rate sensitive. A weaker influence of air humidity at ultrasonic frequencies may lead to prolonged lifetimes in some alloys, and tests in high humidity or distilled water can better approximate environmental conditions at low frequencies. High-strength steels are insensitive to the cycling frequency. Strain rate sensitivity of ferrite causes prolonged lifetimes in those steels that show crack initiation in the ferritic phase. Austenitic stainless steels are less prone to frequency effects. Fatigue properties of titanium alloys and nickel alloys are insensitive to testing frequency. Limited data for magnesium alloys and graphite suggest no frequency influence. Ultrasonic fatigue tests of a glass fibre-reinforced polymer delivered comparable lifetimes to servo-hydraulic tests, suggesting that high-frequency testing is, in principle, applicable to fibre-reinforced polymer composites. The use of equipment with closed-loop control of vibration amplitude and resonance frequency is strongly advised since this guarantees high accuracy and reproducibility of ultrasonic tests. Pulsed loading and appropriate cooling serve to avoid specimen heating.

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High-resolution compositional mapping of surfaces in non-contact atomic force microscopy by a new multi-frequency excitation

Ultramicroscopy ◽

10.1016/j.ultramic.2021.113317 ◽

2021 ◽

pp. 113317

Author(s):

Mostafa Ghanbari Kouchaksaraei ◽

Arash Bahrami

Keyword(s):

Atomic Force Microscopy ◽

High Resolution ◽

Force Microscopy ◽

Atomic Force ◽

Frequency Excitation

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Sum-frequency excitation of coherent magnons

Physical Review B ◽

10.1103/physrevb.103.094407 ◽

2021 ◽

Vol 103 (9) ◽

Author(s):

Dominik M. Juraschek ◽

Derek S. Wang ◽

Prineha Narang

Keyword(s):

Sum Frequency ◽

Frequency Excitation

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Modeling of Dual Excited Synchronous Generator with slip frequency excitation

2020 IEEE First International Conference on Smart Technologies for Power, Energy and Control (STPEC) ◽

10.1109/stpec49749.2020.9297716 ◽

2020 ◽

Author(s):

A. Ajaysekhar Reddy ◽

Sunil S. Bhat

Keyword(s):

Synchronous Generator ◽

Frequency Excitation ◽

Slip Frequency

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Optimization of Ultrasonic-Assisted Extraction, Characterization, and Antioxidant Activities of Polysaccharides From Sojae Semen Praeparatum

Natural Product Communications ◽

10.1177/1934578x211020622 ◽

2021 ◽

Vol 16 (5) ◽

pp. 1934578X2110206

Author(s):

Yongshuai Jing ◽

Ruijuan Zhang ◽

Lan Li ◽

Danshen Zhang ◽

Yu Liu ◽

...

Keyword(s):

Antioxidant Activities ◽

Deae Cellulose ◽

Chemical Compositions ◽

Hydroxyl Groups ◽

Ultrasonic Frequency ◽

Ultrasonic Power ◽

Assisted Extraction ◽

Ultrasonic Time ◽

Ultrasonic Assisted ◽

Ultrasonic Assisted Extraction

In this study, response surface methodology (RSM) was used to optimize the ultrasonic-assisted extraction parameters of Sojae Semen Praeparatum polysaccharides (SSPP-80), the optimum conditions were determined as follows: ultrasonic frequency of 100 W, ultrasonic power of 80 Hz, ultrasonic temperature of 52℃, ultrasonic time of 23 minutes, and liquid to raw material ratio of 40 mL/g. Based on these conditions, polysaccharides extraction rate was 7.72% ± 0.26%. Then, 2 novel polysaccharides (SSPP-80‐1, SSPP-80‐2) were isolated from SSPP by DEAE-cellulose 52 chromatography. The chemical compositions, physicochemical properties, and structure of SSPPs were investigated by simultaneous thermal analyzer (TGA), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FI-IR), and high-performance liquid chromatography (HPLC). The results showed that SSPP-80 and 2 fractions were mainly composed of mannose (Man), glucose (Glc), galactose (Gal), xylose (Xyl), and arabinose (Ara). In addition, the antioxidant activities were evaluated against the DPPH and hydroxyl radical in vitro, the IC50 of SSPP-80, SSPP-80‐1 and SSPP-80‐2 against DPPH free radical were 4.407, 8.267, and 5.204 mg/mL, respectively, whereas the IC50values for removing hydroxyl groups were 5.318, 3.516, and 4.016 mg/mL, respectively. It demonstrated that SSPP-80 and 2 fractions had certain antioxidant activity. Theoretical basis for use of Sojae Semen Praeparatum polysaccharides was provided by this study.

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