Three-layer Permutation of the Phonionic Structure and the Influence of the Environment

2018 ◽  
Vol 69 (9) ◽  
pp. 2571-2574
Author(s):  
Michal Szota
Keyword(s):  
Layer Structure ◽  
Middle Layer ◽  
Production Costs ◽  
Frequency Range ◽  
Different Types ◽  
Transmission Structure ◽  
Materials Used ◽  
The Impact ◽  
Wave Filters ◽  
Different Thickness

The study investigated the influence of permutation of a three-layer structure on the phononic system transmission. Phononic structures are used as mechanical wave filters. These composites are designed and manufactured to have specific properties. The most important property is the presence of phononic bandgaps (PhBG) in these structures. They are designed so that the PhBG occurs in a given frequency range. Knowledge of the impact of deployment of the layets in the structure allows better design of these filters. The analysis was carried out using the transmission matrix method (TMM) algorithm. The transmission structures was examined for all permutations of a system of three layers made of different materials. The structure consisted of mercury, epoxy, rubber and PNM-0.38PT. The materials are chosen so that their characteristics largely differ. The structure was surrounded by water. The tests were carried out for the frequency range up to 1 MHz. Cases with different thickness of layers were analyzed. The tests have shown that regardless of the layer thickness, only three types of transmission structures exist in the six permutations of the system. Systems in which the middle layer remained unchanged, while the outermost layers were changed, were characterized by the same transmission structure. Increasing the thickness of the layers increased the number of transmission bands. Transmission strongly depends on the environment.The absorption of the materials used was not taken into account in the work. Interesting results can be obtained by analyzing the permutation of more complex structures. Changing the order of layers in the filter without changing its characteristics may affect the reduction of production costs and easier design of structures with given properties. The article shows repeating phononic transmission structure for different types of layers alignment.

Influence of various multilayer LTCC systems on dielectric properties’ stability in GHz frequency range

2016 ◽  
Vol 33 (3) ◽  
pp. 136-140 ◽  
Author(s):  
Tibor Rovensky ◽  
Alena Pietrikova ◽  
Igor Vehec ◽  
Martin Kmec
Keyword(s):  
Dielectric Properties ◽  
Design Methodology ◽  
Middle Layer ◽  
Ring Resonators ◽  
Frequency Range ◽  
Content Type ◽  
Different Types ◽  
Good Repeatability ◽  
Microstrip Ring ◽  
Multilayer Substrate

Purpose The purpose of this paper is to create multilayer substrate (composite) from various low temperature co-fired ceramic (LTCC) substrates by their mutual combinations and to analyse influence of these multilayer substrates on dielectric properties in GHz frequency range. Design/methodology/approach GreenTape 951, GreenTape 9K7 and Murata LFC were used to create compound multilayer substrates that include three layers: middle layer is from Murata LFC, and both upper and bottom layers are either from GreenTape 951 or GreenTape 9K7. Shrinkage in all x-, y- and z-axes of all substrates including multilayer substrates were analysed, and influence of different shrinkage on dielectric properties was examined by microstrip ring resonators applied on all mentioned of substrates. Findings The middle layer of Murata LFC has significant influence on shrinkage value of composites which has a good repeatability and minimalizes problems with design of multilayer LTCC devices. Impact of middle layer from Murata LFC on dielectric constant is not significant, but on the other hand Q factor (loss tangent) of these composites is increased according to inhomogeneity between single LTCC layers, especially at frequency around 6 GHz. Originality/value The novelty of this work lies in creating multilayers systems from different types of LTCC substrates to find combination with the most suitable physical and dielectric properties for various purposes in GHz range applications.

Numerical Modeling and Experimental Research of the Perforation Phenomenon of Certain Materials Used for Individual Protection by Bullets

2017 ◽  
Vol 23 (3) ◽  
pp. 174-179
Author(s):  
Florin Ilie ◽  
Nicolae Moro
Keyword(s):  
Numerical Modeling ◽  
Modeling And Simulation ◽  
Experimental Research ◽  
Ballistic Protection ◽  
Different Types ◽  
Individual Protection ◽  
Range Testing ◽  
Materials Used ◽  
The Individual ◽  
The Impact

Abstract The paper captures two aspects related to the phenomenon of impact between bullets and different types of materials used for the individual protection of the militaries, for the same type of ammunition and for the same configuration of the ballistic protection system, both in the case of the activity of experimental shooting range testing, as well as in the case of the modeling and simulation of the impact between the bullet and the protection materials.

scholarly journals Characteristics of Specialised Firefighter Clothing Used in Poland – the Thermal Parameters

2020 ◽  
Vol 28 (1(139)) ◽  
pp. 65-70
Author(s):  
Magdalena Młynarczyk
Keyword(s):  
Thermal Insulation ◽  
Protective Clothing ◽  
Thermal Parameters ◽  
Thermal Manikin ◽  
Test Results ◽  
Evaporative Resistance ◽  
Different Types ◽  
Local Thermal Insulation ◽  
Materials Used ◽  
The Impact

This paper describes the characteristic thermal parameters of firefighters’ personal protective clothing (FFPPC) used in Poland. The total thermal insulation and evaporative resistance of three different types of FFPPC were measured and used on a thermal manikin. Next, the results were compared. Based on the analyses and calculations of the test results, it was shown that FFPPC provides a barrier to the heat exchange between the user and the surrounding environment. Differences in the local thermal insulation can be triggered not only by the material used but they can also be attributable to clothes fitted on the manikin. The biggest differences can be noted on the segments forming part of the manikin’s trunk. No difference was found in the evaporative resistance between the clothes tested. In order to examine further the impact of the materials used on thermal parameters of protective clothing, it is necessary to carry out an analysis of the impact of individual layers.

SIFAT FISIK DAN MEKANIK PAPAN PARTIKEL DARI LIMBAH PLASTIK JENIS HDPE (High Density Polyetylene) DAN RANTING/CABANG KARET (Hevea brasiliensis Muell.Arg)

2011 ◽  
Vol 3 (1) ◽  
pp. 7
Author(s):  
Sari Mirad Noor
Keyword(s):  
Mechanical Properties ◽  
Water Absorption ◽  
Raw Materials ◽  
Urea Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Plastic Waste ◽  
High Density ◽  
Different Types ◽  
Materials Used ◽  
The Impact

The need of log increace rapidly, mean while forest product decrease, so efficiency on wood process should be done wisely, in the other hand plastic waste is uncompossed material, become an environmental problems. This research aims to determine the impact of particles of type HDPE plastic wastes and twigs/branches of rubber on some physical and mechanical properties of wood. Physical properties have been tested for water content, density, thickness, and water absorption. Although mechanical properties tests were tough Broken/Module of Rufture (MOR) and the preservation of architecture/modulus of elasticity (MOE).     The raw materials used are polyethylene of high density of waste plastic and rubber adhesive urea formaldehyde branch branch. Experimental design used the randomized Completely Design (RCD) 5 x 4, in which each treatment became much like 5 times replicated).The treatment used is the diversity of the composition of the waste of plastic of different types of polyethylene of high density provides a significant effect on the content of water, water absorption, the density and the development of thickness. With regard to the persistence and the fracture of the arch determination not to give a significant effect.Keywords: physical and mechanical properties, particle board, HDPE plastic waste, branch/twig of  rubber.

scholarly journals Implementation of Halal Product Assurance in the Pharmaceutical Sector in Indonesia

2021 ◽  
Vol 1 (3) ◽  
Author(s):  
Resti Dian Luthviati ◽  
Suviwat Jenvitchuwong
Keyword(s):  
Value Chain ◽  
Raw Materials ◽  
Production Costs ◽  
Pharmaceutical Sector ◽  
Total Change ◽  
Drug Prices ◽  
Different Types ◽  
Distribution Process ◽  
The Impact ◽  
Economic Capacity

The goal of this research is to determine and assess the implementation of halal certification for the pharmaceutical business in accordance with Law Number 33 of 2014 on Halal Product Assurance, as well as the variables that hinder and support its implementation. The impact of the JPH Law on the process value chain and supply chain of drugs and vaccines results in a total change in the pharmaceutical industry, including changes in ingredients resulting in reprocessing of quality, safety, and efficacy, changes in the distribution process, addition of personnel or staff, decreased economic capacity of the industry due to increased production costs, and there is a decrease in the industry's economic capacity due to increased costs of production. The halal status of a product has become a must-have for all consumers, particularly Muslims. Some parties, particularly the pharmaceutical business, continue to oppose to the existence of Law No. 33 of 2014 concerning Halal Product Guarantee. The supply of special facilities, such as rooms, equipment, and human resources, will significantly raise costs, resulting in higher drug prices and a reduction in people's access to the items they truly require for health care. Currently, the pharmaceutical sector must import 95 percent or more of its raw materials, totaling 150,000 items, in order to make about 30,000 different types of pharmaceuticals in the country.

scholarly journals Obudowy dźwiękochłonno-izolacyjne urządzeń ultradźwiękowych, ograniczające poziom hałasu przenikającego do środowiska. Wyniki badań własnych

2021 ◽  
Vol 600 (9) ◽  
pp. 22-28
Author(s):  
Witold Mikulski ◽  
Keyword(s):  
Health Risk ◽  
Frequency Range ◽  
Effective Measure ◽  
Close Proximity ◽  
Ultrasonic Devices ◽  
Materials Used ◽  
Technical Solutions ◽  
The Impact

The article discusses the technical solutions of sound-absorbing and sound-insulating enclosures for devices that are sources of ultrasonic noise (sound frequencies range of 10-40 kHz). Due to the high health risk of employees operating ultrasonic technological devices and the fact that they are in close proximity to these devices, it is necessary to use an effective measure to reduce this risk, i.e. sound-insulating enclosures. So far, however, the rules for the use of such casings and the sound-insulating and sound-absorbing properties of their materials (in this frequency range) have not been defined. The article presents the results of own research on the impact of the materials used to make enclosures, linings of casings and the presence of openings (hole) in casings on the level of noise emitted by ultrasonic devices that penetrates into the environment.

scholarly journals Review on the Thermal Performance on the Basis of Different Types of Material used in Ball Bearings

2021 ◽  
pp. 61-66
Author(s):  
Vinay Kumar Shukla
Keyword(s):  
Thermal Performance ◽  
Ball Bearings ◽  
Operating Environment ◽  
Rolling Bearings ◽  
Movable Object ◽  
Different Types ◽  
Operations And Maintenance ◽  
Frictional Forces ◽  
Materials Used ◽  
The Impact

Bearing is a movable object, so frictional forces must be overcome in terms of moving the Bearing. To decrease the friction force on the movable methodology, different kinds of bearings have been used. The bearing gets its characterized by the fact that it is used to support a rotating axle or shaft. Because rolling bearings utilize balls or rollers, they are referred to as "rolling components." one can measure bearing expected lifespan depending on the material exhaustion if one can understand the operations and maintenance of loads and speeds. These computations should be based on the assumption that now the bearing is appropriately installed, lubricated, and moreover treated. It is unable to account for the impact of detrimental operating environment. Damaged bearing has a significant economic and industrial implications. Numerous substance are used in the bearing sector to several bearing elements. To achieve maximum bearing performance and durability, the products are deposited to obtain intended characteristics. The components listed in this are the most frequently used. The different materials used in ball bearings are discussed in this paper.

scholarly journals Materials for Photovoltaics: State of Art and Recent Developments

2019 ◽  
Vol 20 (4) ◽  
pp. 976 ◽  
Author(s):  
José Luceño-Sánchez ◽  
Ana Díez-Pascual ◽  
Rafael Peña Capilla
Keyword(s):  
Low Cost ◽  
Photovoltaic Cell ◽  
Production Costs ◽  
Lower Efficiency ◽  
Cell Technology ◽  
Recent Developments ◽  
Materials Used ◽  
The Stability ◽  
The Impact ◽  
State Of Art

In recent years, photovoltaic cell technology has grown extraordinarily as a sustainable source of energy, as a consequence of the increasing concern over the impact of fossil fuel-based energy on global warming and climate change. The different photovoltaic cells developed up to date can be classified into four main categories called generations (GEN), and the current market is mainly covered by the first two GEN. The 1GEN (mono or polycrystalline silicon cells and gallium arsenide) comprises well-known medium/low cost technologies that lead to moderate yields. The 2GEN (thin-film technologies) includes devices that have lower efficiency albeit are cheaper to manufacture. The 3GEN presents the use of novel materials, as well as a great variability of designs, and comprises expensive but very efficient cells. The 4GEN, also known as “inorganics-in-organics”, combines the low cost/flexibility of polymer thin films with the stability of novel inorganic nanostructures (i.e., metal nanoparticles and metal oxides) with organic-based nanomaterials (i.e., carbon nanotubes, graphene and its derivatives), and are currently under investigation. The main goal of this review is to show the current state of art on photovoltaic cell technology in terms of the materials used for the manufacture, efficiency and production costs. A comprehensive comparative analysis of the four generations is performed, including the device architectures, their advantages and limitations. Special emphasis is placed on the 4GEN, where the diverse roles of the organic and nano-components are discussed. Finally, conclusions and future perspectives are summarized.

Explosive Sensitivity Influence on One- and Two-Layered Reactive Armors’ Behavior

2010 ◽  
Vol 77 (5) ◽  
Author(s):  
Adam Wiśniewski
Keyword(s):  
High Explosive ◽  
Propagation Speed ◽  
Cylindrical Symmetry ◽  
Strong Discontinuity ◽  
Different Types ◽  
Pressure Impact ◽  
Computer Codes ◽  
Explosive Sensitivity ◽  
The Impact ◽  
Different Thickness

The use of different explosive reactive armor reactive cassettes is shown. Functioning rules of one- and two-layered reactive cassettes are presented. The paper demonstrates different kinds of tests with explosive reactive armour Wisniewski Adam (ERAWA) cassettes. There are some examples of the simulation of impact of different types armour piercing (AP) and high explosive anti-tank (HEAT) ammunition on these cassettes. Simulation was based on “free points” computer codes. The propagation of the detonative wave in the explosive (PBX 9404 and RDX) has been described with the use of the approximation of the so-called “detonative optics,” in which the front of the detonative wave is a surface of the strong discontinuity of the well-known shape (for the punctual initiation—the front is spherical) of the propagation speed, and the parameters of the medium on this surface are defined by the Chapman–Jouguet’s point. Scattering of products of detonation and their influence on the liner of the RPG-7M projectile are described with the use of equations of the hydrodynamics for the cylindrical symmetry. The results of the simulation process of the impact of AP ammunition of 7.62 mm, 12.7 mm, 14.5 mm, and 125 mm caliber, the type of armour piercing fin stabilized discarting sabot (APFSDS), are illustrated in figures. The changing of the following parameters on the axis, i.e., density, thickness, collapsing velocity, and pressure while penetrating of cassettes in time function, is presented. The next step to test the sensitivity of different types of explosive reactive cassettes containing different explosive layers placed on target, is the observation of their reaction to the impact of kinetic energy ammunition. Explosives contain different percentages of wax. The examples of reaction of the two-layered explosive of different thickness with different contents of wax after projectile impact are illustrated. Computer analysis of the parameters’ changes on the axis of the projectile’s penetration into explosive reactive cassettes, i.e., of density, thickness, pressure, impact velocity for different thicknesses of layers of these cassettes, and the projectile type and velocity 800 m/s and 1800 m/s, enables to know the initiation conditions of these cassettes’ explosive. The use of computer simulation makes possible to know the influence of the quantity of wax on the sensitivity of different thicknesses of explosives of one- and two-layered reactive cassettes.

scholarly journals Mechanical Properties Of 3D-Structure Composites Based On Warp-Knitted Spacer Fabrics

2015 ◽  
Vol 15 (2) ◽  
pp. 127-137 ◽  
Author(s):  
Si Chen ◽  
Hai-ru Long ◽  
Ying-hao Liu ◽  
Feng-chao Hu
Keyword(s):  
Mechanical Properties ◽  
Mechanical Performance ◽  
Layer Structure ◽  
Structural Parameters ◽  
3D Structure ◽  
Three Dimension ◽  
Different Types ◽  
Spacer Fabrics ◽  
Flexible Polyurethane ◽  
The Impact

Abstract In this paper, the mechanical properties (compression and impact behaviours) of three-dimension structure (3D-structure) composites based on warp-knitted spacer fabrics have been thoroughly investigated. In order to discuss the effect of fabric structural parameters on the mechanical performance of composites, six different types of warp-knitted spacer fabrics having different structural parameters (such as outer layer structure, diameter of spacer yarn, spacer yarn inclination angle and thickness) were involved for comparison study. The 3D-structure composites were fabricated based on a flexible polyurethane foam. The produced composites were characterised for compression and impact properties. The findings obtained indicate that the fabric structural parameters have strong influence on the compression and impact responses of 3D-structure composites. Additionally, the impact test carried out on the 3D-structure composites shows that the impact loads do not affect the integrity of composite structure. All the results reveal that the product exhibits promising mechanical performance and its service life can be sustained.

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