scholarly journals The study of the effectiveness of sound insulation of gypsum wall boards with “Shimast” coating

2020 ◽  
Vol 320 ◽  
pp. 00033
Author(s):  
Semen Totunov ◽  
Michael Ivanov ◽  
Olga Ivanova
Keyword(s):  
Thin Layer ◽  
Experimental Studies ◽  
Single Layer ◽  
Sound Insulation ◽  
Reverberation Chamber ◽  
Research Results ◽  
Partition Walls ◽  
Acoustic Reverberation ◽  
Layer Coating

The article presents the experimental studies of sound insulation of a single-layer barrier made of gypsum wall boards with a thin-layer coating. The coating consists of a viscous base and glass airless microgranules. The coating increases the efficiency of reducing air noise. The material is applied as a normal paint by spraying on the surface. The research results have been obtained in an acoustic reverberation chamber designed to study the partition walls effectiveness.

A study on the electromagnetic properties of graphite/bismuth/bismuth oxide-coated composites

2021 ◽  
pp. 004051752199434
Author(s):  
Yuanjun Liu ◽  
Yanfeng Yang
Keyword(s):  
Mechanical Property ◽  
Dielectric Constant ◽  
Bismuth Oxide ◽  
Control Variable ◽  
Single Layer ◽  
Polarization Property ◽  
Electromagnetic Properties ◽  
Shielding Effectiveness ◽  
Absorbing Property ◽  
Layer Coating

Coating is a commonly used process for the preparation of protective textiles. In this study, the absorbing coated composite material was prepared by a coating process, using plain weave polyester/cotton fabric as the base fabric, PU-2540 polyurethane as the binder, and graphite, bismuth and bismuth oxide as the functional particles. The effects of the content of functional particles and the ratio of functional particles on the dielectric constant, reflection loss, shielding effectiveness, and tensile strength of the single-layer coating composites were studied using the control variable method. The results showed that when the frequency was 1–1000 MHz, the real and imaginary parts of the dielectric constant, the tangential value of the loss angle, and the tensile value increased with the increase of the coating content, and the polarization, loss and attenuation property, and mechanical property of the electromagnetic wave were enhanced. When graphite, bismuth, and bismuth oxide was mixed at the ratio of 9:0:0 in weight, the polarization property was the best. When mixed at the ratio of 6:1:2 in weight, the loss performance and attenuation ability were the best. When mixed at the ratio of 6:3:0 in weight, the absorbing property and mechanical property were the best. When mixed at the ratio of 6:2:1 in weight, the shielding property was the best.

Treated Textile Electrostatic Properties Study

2020 ◽  
Vol 992 ◽  
pp. 439-444
Author(s):  
I.V. Cherunova ◽  
S.S. Tashpulatov ◽  
S.V. Kurenova
Keyword(s):  
Experimental Studies ◽  
Material Structure ◽  
Ministry Of Education ◽  
Research Results ◽  
Textile Materials ◽  
Electrostatic Properties ◽  
Film Forming ◽  
Study Results ◽  
Water Proofing ◽  
Textile Fabric

In the article research results are presented, which aim to provide treated textile electrostatic properties study. In the article research results are presented, which aim to provide find out abilities of an anti-electrostatic treatment and binding agents for it in treatment of special textile materials and their dependance from modes of operating textile washing. Results of determine a composition and abilities of a functional impregnation; develop a method to study values of electrostatic field for tribocharging conditions of textile materialsare; experimental studies of electrostatic values of materials with functional treatment depending on operating washing modes also presented here. Study results allowed to establish efficiency of the proposed combination of anti-electrostatic active composition based on 5 % solution of dialkyldimethylammonium chloride with a binding agent with the effect to preserve the treatment in the material structure and content of which is 4 % in application of textile fabric with widely used fiber content (cotton 53 %, polyester + oil and water-proofing finish). Acrylic dispersion is stable film-forming component suitable in preserving anti-electrostatic treatment on the surface of a textile material. The research was made in Don State Technical University within the framework of State Assignment of the Ministry of education and science of Russia under the project 11.9194.2017/BCh.

scholarly journals Finite Element Prediction for the Internal Stresses of (Ti,Al)N Coatings

2016 ◽  
Vol 61 (1) ◽  
pp. 149-152 ◽  
Author(s):  
L.W. Żukowska ◽  
A. Śliwa ◽  
J. Mikuła ◽  
M. Bonek ◽  
W. Kwaśny ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Computer Simulation ◽  
Finite Element ◽  
Experimental Studies ◽  
Single Layer ◽  
Internal Stresses ◽  
Pvd Coatings ◽  
Properties Of Coatings ◽  
Gradient Coatings ◽  
Element Method

The general topic of this paper is the computer simulation with use of finite element method (FEM) for determining the internal stresses of selected gradient and single-layer PVD coatings deposited on the sintered tool materials, including cemented carbides, cermets and Al2O3+TiC type oxide tool ceramics by cathodic arc evaporation CAE-PVD method. Developing an appropriate model allows the prediction of properties of PVD coatings, which are also the criterion of their selection for specific items, based on the parameters of technological processes. In addition, developed model can to a large extent eliminate the need for expensive and time-consuming experimental studies for the computer simulation. Developed models of internal stresses were performed with use of finite element method in ANSYS environment. The experimental values of stresses were calculated using the X-ray sin2ψ technique. The computer simulation results were compared with the experimental results. Microhardness and adhesion as well as wear range were measured to investigate the influence of stress distribution on the mechanical and functional properties of coatings. It was stated that occurrence of compressive stresses on the surface of gradient coating has advantageous influence on their mechanical properties, especially on microhardness. Absolute value reduction of internal stresses in the connection zone in case of the gradient coatings takes profitably effects on improvement the adhesion of coatings. It can be one of the most important reasons of increase the wear resistance of gradient coatings in comparison to single-layer coatings.

scholarly journals Design, fabrication and experimental studies of compliant flexure diaphragm for micro pump

2018 ◽  
Vol 7 (2.21) ◽  
pp. 66 ◽  
Author(s):  
R Roopa ◽  
P Navin Karanth ◽  
S M. Kulkarni
Keyword(s):  
Polyvinylidene Fluoride ◽  
High Performance ◽  
Experimental Studies ◽  
Single Layer ◽  
Operating Voltage ◽  
Driving Voltage ◽  
Element Analysis ◽  
Central Deflection ◽  
Large Numbers ◽  
Micro Pump

This study reports the performance of piezo actuated compliant flexure diaphragm for micropump and MEMS application. To achieve the high performance of diaphragm at the low operating voltage compliant flexure diaphragm design is introduced. Very limited work has done on the diaphragms of micropump. Large numbers of mechanical micropumps have used plane diaphragms. The central deflection of diaphragm plays an important role in defining the micropump performance. The flow rate of mechanical type micropump strongly depends on the central deflection of diaphragm. In this paper compliant flexure diaphragms are designed for micropump to achieve higher deflection at lower operating voltage. Finite element analysis of compliant flexure diaphragm with single layer PVDF (Polyvinylidene fluoride) actuator is simulated in COMSOL. Compliant flexure diaphragms with a different number of flexures are analyzed. The central deflection of compliant flexure diaphragms is measured for driving voltages of 90V to 140V in 10 steps. The deflection of the compliant flexure diaphragm mainly depends on flexure width and length, the number of flexures in the diaphragm, PVDF thickness, diaphragm thickness and driving voltage. Use of compliant flexure diaphragm for micropump will reduce the mass and driving voltage of micropump. An attempt is made to compare the results of compliant flexure diaphragms with plane diaphragms. From the experimental results it is noticed that the compliant flexure diaphragm deflection is twice that of the plane diaphragm at same driving voltage. Deflection of three flexure and four flexure compliant diaphragms is 10.5µm and 11.5µm respectively at 140V.  

scholarly journals EXPERIMENTAL STUDIES ON SOUND INSULATION PROPERTIES OF TRADITIONAL WOODEN HOUSES

1984 ◽  
Vol 345 (0) ◽  
pp. 218-225 ◽  
Author(s):  
MASAHITO YASUOKA ◽  
HIDEKI TACHIBANA ◽  
HIROSHI TANAKA ◽  
AKIHIRO TAMURA
Keyword(s):  
Experimental Studies ◽  
Sound Insulation

scholarly journals Методы определения характеристик звукопоглощения строительных материалов и звукоизоляции конструкций (обзор)

2020 ◽  
Vol 45 (4) ◽  
Author(s):  
Keyword(s):  
Noise Reduction ◽  
Sound Absorption ◽  
Building Materials ◽  
Developed Countries ◽  
Reduction Factor ◽  
Sound Insulation ◽  
Reverberation Chamber ◽  
Normative Documents ◽  
Urban Conditions ◽  
First Time

Исследование акустических характеристик строительных материалов и конструкций необходимо для комфортной жизни людей в городских условиях. Несмотря на то что в нормативных документах развитых государств есть ряд методов их определения, единого понимания самих характеристик и путей их адекватного определения до сих пор нет. В настоящей работе мы попытались систематизировать и дать критический обзор нормативных документов, содержащих методы определения звукопоглощающих свойств материалов и звукоизоляционных характеристик конструкций. Впервые выявлены присущие разным методам закономерности определения характеристик звукопоглощения и звукоизоляции. Определены наиболее характерные показатели звукопоглощения. Произведено ранжирование по коэффициенту уменьшения шума NRC наиболее часто применяемых строительных материалов. Названы области применения рассматриваемых методик, проанализированы их преимущества и ограничения. Ключевые слова: коэффициент уменьшения шума, звукопоглотитель, импедансная труба, реверберационная камера The study of the acoustic characteristics of building materials and structures is necessary for provision of comfortable life of people in urban conditions. Despite the fact that in the normative documents of developed countries there are a number of methods for their determination, there is still no common understanding of the characteristics themselves and the ways of their adequate determination. In this work we tried to systematize and give a critical review of regulatory documents containing the methods for determining the sound-absorbing properties of materials and the sound-insulating characteristics of structures. For the first time the regularities in determination the characteristics of sound absorption and sound insulation inherent in different methods have been revealed. The most characteristic indicators of sound absorption have been determined. The ranking of the most commonly used building materials was made according to the noise reduction factor (NRC). The areas of application of the considered methods are presented, their advantages and limitations are analyzed. Keywords: noise reduction factor, sound absorber, impedance tube, reverberation chamber

scholarly journals EFFICIENT ACOUSTIC COMPOSITE PANELS BASED ON GRAPHITE

2021 ◽  
Vol 6 (4) ◽  
pp. 82-90
Author(s):  
E. Fanina
Keyword(s):  
Experimental Studies ◽  
Three Dimensional ◽  
Sound Field ◽  
Fire Retardant ◽  
Pyramidal Cells ◽  
Sound Insulation ◽  
Composite Panels ◽  
Thin Membrane ◽  
Reverberation Time ◽  
Acoustic Characteristics

A set of experimental studies is carried out to determine the acoustic characteristics of three-dimensional panels of fixed thickness made of carbon-based composite material installed in the opening between the reverberation chambers. Sound insulation indices are determined when they are excited by a diffuse sound field in wide frequency ranges. The reverberation time in model chambers with different partition configurations is calculated. The optimal configuration of the partition with pyramidal cells to reduce the reverberation time in the rooms is determined. The use of graphite in the form of thin membrane applied to various surfaces can significantly reduce the sound pressure levels in the room and increase the sound insulation indices of air noise. In addition to thin membrane, graphite can be used as an additive in composite materials for sound insulation purposes. It is shown that the characteristics of such panels are quite universal. The measured acoustic characteristics of composite panels are compared with similar characteristics of traditional materials. It is determined that the composition belongs to the I group of fire-retardant efficiency and can be recommended for use as a fire-retardant material. The developed acoustic material is an effective absorbing agent that solves problems in architectural acoustics, echo cancellation in construction and architecture. Similar to metamaterials, natural and artificial graphites allow to solve these problems with small volumes and masses using simple and inexpensive technologies.

scholarly journals The Anti-Neuroinflammatory Effect of Fuzi and Ganjiang Extraction on LPS-Induced BV2 Microglia and Its Intervention Function on Depression-Like Behavior of Cancer-Related Fatigue Model Mice

2021 ◽  
Vol 12 ◽  
Author(s):  
Songwei Yang ◽  
Yantao Yang ◽  
Cong Chen ◽  
Huiqin Wang ◽  
Qidi Ai ◽  
...  
Keyword(s):  
Chinese Medicine ◽  
Traditional Chinese Medicine ◽  
Inflammatory Mediators ◽  
Critical Role ◽  
Chinese Herb ◽  
Experimental Studies ◽  
Research Results ◽  
Cancer Related Fatigue

The Chinese herb couple Fuzi and Ganjiang (FG) has been a classic combination of traditional Chinese medicine that is commonly used clinically in China for nearly 2000 years. Traditional Chinese medicine suggests that FG can treat various ailments, including heart failure, fatigue, gastrointestinal upset, and depression. Neuroinflammation is one of the main pathogenesis of many neurodegenerative diseases in which microglia cells play a critical role in the occurrence and development of neuroinflammation. FG has been clinically proven to have an efficient therapeutic effect on depression and other neurological disorders, but its mechanism remains unknown. Cancer-related fatigue (CRF) is a serious threat to the quality of life of cancer patients and is characterized by both physical and psychological fatigue. Recent studies have found that neuroinflammation is a key inducement leading to the occurrence and development of CRF. Traditional Chinese medicine theory believes that extreme fatigue and depressive symptoms of CRF are related to Yang deficiency, and the application of Yang tonic drugs such as Fuzi and Ganjiang can relieve CRF symptoms, but the underlying mechanisms remain unknown. In order to define whether FG can inhibit CRF depression-like behavior by suppressing neuroinflammation, we conducted a series of experimental studies in vitro and in vivo. According to the UPLC-Q-TOF/MSE results, we speculated that there were 49 compounds in the FG extraction, among which 30 compounds were derived from Fuzi and 19 compounds were derived from Ganjiang. Our research data showed that FG can effectively reduce the production of pro-inflammatory mediators IL-6, TNF-α, ROS, NO, and PGE2 and suppress the expression of iNOS and COX2, which were related to the inhibition of NF-κB/activation of Nrf2/HO-1 signaling pathways. In addition, our research results revealed that FG can improve the depression-like behavior performance of CRF model mice in the tail suspension test, open field test, elevated plus maze test, and forced swimming test, which were associated with the inhibition of the expression of inflammatory mediators iNOS and COX2 in the prefrontal cortex and hippocampus of CRF model mice. Those research results suggested that FG has a satisfactory effect on depression-like behavior of CRF, which was related to the inhibition of neuroinflammation.

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