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The purpose of this paper is to describe a new apparatus for testing acoustic insulating, air permeating and water vapor transfer properties of fibrous assemblies with density variation.

An apparatus is designed and built in order to investigate the acoustic insulating, air permeating and water vapor transfer properties of fiber assemblies with density variation. The apparatus mainly consists of three chambers, just like the structure of a syringe. The three properties can be measured by placing different sensors at the corresponding chambers. The material density variation can be realized by compression.

The new apparatus can realize the measurement of the three properties with density variation, which provides a new perspective to study the physical property of fibrous assemblies.

The paper introduces a new apparatus for testing acoustic insulating, air permeating and water vapor transfer properties of fibrous assemblies with density variation.

Delineating where stability occurs in a contract provides the window of opportunity for procurement officials to positively affect cost and schedule outcomes. While the concept of a Cost Performance Index (CPI) "stability rule" has been routinely cited by Earned Value Management (EVM) authors since the early 1990's, more recent research questions the veracity of this stability rule. This paper resolves the controversy by demonstrating that the definition of stability matters. We find a morphing of the stability definition over time, with three separate definitions permeating the literature. Next, an analysis of Department of Defense contracts for both cost and schedule stability properties finds that the veracity of the stability rule is intricately tied to the definition used.

This study aims to shed light on the corrosion behavior of X80 steel when sulfate-reducing bacteria (SRB) and permeating hydrogen interact.

In this study, electrochemical tests were conducted between 25 and 55 °C, and the surface morphology of the specimen was observed using scanning electron microscopy and three-dimensional photos. The composition of the oxide film was characterized by X-ray photoelectron spectroscopy (XPS).

Under the condition of 6 MPa simulated natural gas (15% H₂), the content of S-containing compounds (FeS and FeSO₄) in the corrosion products on the surface of the specimen decreases from 60.8% to 54.4%. This finding indicates that hydrogen permeation inhibits the metabolic processes of SRB in this environment. By comparing the hydrogen-uncharged specimen, it was found that under the condition of 6 MPa simulated natural gas (15% H₂) hydrogen charging, the uniform corrosion on the X80 surface was weakened, and the protection of the oxide film on the specimen surface in this environment was better than that without hydrogen charging.

To the best of the authors’ knowledge, most of these existing studies have focused on the effect of hydrogen on the mechanical properties of materials and very little is known about corrosion behavior in the hydrogen environment. In this study, a self-designed small gas phase hydrogen charging device was used to study the X80 surface corrosion behavior in the environment of the H₂-doped natural gas pipeline.

Due to the excellent functionality of graphene, the research on fiber modification by graphene has been receiving more and more attentions recently, and many research findings have been conducted. However, the purpose of this paper is to focus on the fiber modification method and corresponding modified fiber properties, but the research on processing of the modified fiber, especially the textile process, is little. Therefore, in the paper, the properties of one kind of textile GN fiber and the spinning method of the GN fiber blend yarn and the functionalities of corresponding fabric are studied.

In the paper, the properties of nylon fiber modified by graphene (GN) were studied first. Then, according to the tested results, one new blending process of the GN fiber and cotton fiber was given, and corresponding properties of the blend yarns were tested and analyzed. Finally, the knitted fabrics were produced using the spun blend yarns, and the antibacterial property, electromagnetic shielding property, anti-ultraviolet performance, anti-static performance and conventional mechanical, and appearance thermal-wet comfort properties were tested and comparatively analyzed.

The tested results showed that the functionality of all fabrics was effective due to the addition of the graphene in the fiber, especially the antibacterial property. With the increasing of the GN fiber in the blend yarns, the functionality of all fabrics was also increased first and then achieved stability.

One new blending process of the GN fiber and cotton fiber was given. In the spinning, the combed cotton sliver was produced first, and then was torn into small parts of combed cotton sliver fiber by hand. Then, the treated GN fibers and cotton fibers were mixed for the first time, and corresponding GN/C carding sliver was produced. In this blend processing, the mixed cotton fiber was used to improve the sliver processing of the GN fiber. Then, in the drawing process, the required number of GN/C carding sliver and combed cotton sliver were fed simultaneously, and GN fibers and cotton fibers were mixed for the second time, and corresponding four kinds of GN/JC blend yarns were produced. In this blend processing, the mixed cotton fiber was used to regulate the blending ratio.

Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in their efforts to develop and market new products. Looks at the issues from different strategic levels such as corporate, international, military and economic. Presents 31 case studies, including the success of Japan in microchips to the failure of Xerox to sell its invention of the Alto personal computer 3 years before Apple: from the success in DNA and Superconductor research to the success of Sunbeam in inventing and marketing food processors: and from the daring invention and production of atomic energy for survival to the successes of sewing machine inventor Howe in co‐operating on patents to compete in markets. Includes 306 questions and answers in order to qualify concepts introduced.

The purpose of this paper is to investigate effect of material properties in 3D knitted fabrics on thermo-physiological comfort.

In the present study six different spacer fabrics were developed. Among these six fabrics, it was classified into two groups for convenient analysis of results, the first group has been developed using polyester/polypropylene blend with three different proportion and second group with polyester/polypropylene/lycra blend having another three different composition. As a spacer yarn, three different types of 88 dtex polyester monofilament yarn and polyester multifilament yarns (167 dtex and 14.5 tex) were used and 14.5 tex polypropylene and 44 dtex lycra multifilament yarns were also used for the face and back side of the spacer fabrics (Table I). These fabrics were developed in Syntax Pvt Ltd Czech Republic.

The main influence on the water vapour permeability of warp knitted spacer fabrics is the kind of raw material, i.e. fibre wetting and wicking. Also there is no correlation between air permeability and water vapour permeability. It is found that both air permeability and thermal conductivity are closely related to the fabric density. It is also found that the fabric characteristics of spacer fabric show a very significant effect on the air permeability, thermal conductivity and mechanical properties of spacer fabric. Therefore, selection of spacer fabric for winter clothing according to its fabric characteristics.

The main objective of the present study is to produce spacer knitted 3D fabrics suitable for defined climatic conditions to be used as clothing or in sports goods.

New 3D knitted spacer fabrics can be produced with improved comfort properties.

The position of these Irish agitators is illogical and untenable; the remedy they propose is no remedy at all – nevertheless they are talking about the tenure of land and the right to land; and thus a question of worldwide importance is coming to the front.³

Develops an original 12‐step management of technology protocol and applies it to 51 applications which range from Du Pont’s failure in Nylon to the Single Online Trade Exchange for Auto Parts procurement by GM, Ford, Daimler‐Chrysler and Renault‐Nissan. Provides many case studies with regards to the adoption of technology and describes seven chief technology officer characteristics. Discusses common errors when companies invest in technology and considers the probabilities of success. Provides 175 questions and answers to reinforce the concepts introduced. States that this substantial journal is aimed primarily at the present and potential chief technology officer to assist their survival and success in national and international markets.

The purpose of this paper is to study the influence of fibre properties on filtration behavior. Air pollution is a major threat to human beings due to industrialization and urbanization. Among various particles in the atmospheric air, PM 2.5 causes various respiratory problems to human beings and also causes premature engine wear. The primary importance for the filters is higher filtration efficiency with lower pressure drop.

In this research, nonwoven filters were developed with different diameters of polyester fibres such as 0.8d, 1.2d and 6d fibres and different proportions of fibres were used. The Kuwabara cell model was used to derive certain parameters and its effects were analysed. The effect of basis length, solid volume fraction and porosity on filtration behavior was discussed in detail.

The filtration efficiency is higher for particle size from 1–3 µm, when different layers of polyester fibres are used with coarser fibres as the top layer and finer as the bottom layer. The filtration performance is better for layered nonwoven than unimodal nonwoven. The higher proportion of micro-denier fibres results in higher filtration efficiency with higher pressure drop.

The proposed research is more suitable for the particle size of more than 1 µm because of the fibre diameters and its achievable porosity. The filtration efficiency can be increased further by increasing the mass per unit area, which also increases the pressure and is not recommended.

The effect of triple-layers with different diameters of fibres on filtration was analysed. Due to the variation in diameters of fibres in different layers, the filtration performance varies.